Class Definition for Class 192 - CLUTCHES AND POWER-STOP CONTROL

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CLASS 192,	CLUTCHES AND POWER-STOP CONTROL
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SECTION I - CLASS DEFINITION

This class includes clutches, combinations including vortex flow drive and clutch, vortex flow drive and brake, clutch and brake, and clutch and gear; and also includes mechanism for joint control of transmission and clutch, and transmission and brake.

This class includes the control of those various power-transmission means, motors, and brakes the motions of which occur at the completion of a cycle of operations or which are due to contact with the material handled by the machine or to the defective action of the parts of the machine operated or to such operations as arise from the initiation of measures for the safety of the operator.

This class is also the generic locus for clutches and brakes (see below for subclass references).

SECTION II - SUBCLASS REFERENCES TO THE CURRENT CLASS

SEE OR SEARCH THIS CLASS, SUBCLASS:

21.5,

107+, for both clutches and brakes of the subject matter herein classified.

SECTION III - REFERENCES TO OTHER CLASSES

SEE OR SEARCH CLASS:

74,	Machine Element or Mechanism, appropriate subclasses, especially 640+ for clutches or brakes and clutches used to modify or control a gearing organization, where specific gearing structure is claimed.
180,	Motor Vehicles, subclasses 6.2+ for various clutch and brake arrangements providing for steering by driving, where some specific steering by driving vehicle structure is claimed.
188,	Brakes, appropriate subclasses for motor vehicle mounted brakes used in association with clutches, where the clutch is not claimed.
234,	Selective Cutting (e.g., Punching), appropriate subclasses, for the starting and stopping of a selective cutting machine in response to various predetermined conditions; especially subclass 21 for means to stop after a given number of operations, and subclass 51 for unicyclic or nonrepeat drive means.
242,	Winding, Tensioning, or Guiding, subclasses 257+ for a clutch in a fishing reel, subclasses 264+ for a releasable coupling in a fishing reel, subclass 356.6 for a one-way clutch in the drive of a winder of an information bearing carrier, subclasses 394+ for a clutch in a reeling device of general use, subclasses 484.6+ for a helical winding machine drive which may include a clutch, and subclasses 545+ for a clutch in the drive on a convolute winding machine in which particular winding or unwinding structure is specified.
399,	Electrophotography, subclass 210 for damping or braking a slit exposure scanning carriage.
418,	Rotary Expansible Chamber Devices, subclass 69 , for rotary expansible chamber devices combined with a nominally claimed clutch device.
475,	Planetary Gear Transmission Systems or Components, appropriate subclasses, for clutches or brakes and clutches used to modify or control a planetary gearing organization.
477,	Interrelated Power Delivery Controls, Including Engine Control, for interrelated control between an engine and a transmission, clutch, or brake.

SUBCLASSES

[List of Patents for class 192 subclass 3.21]

3.21

VORTEX-FLOW DRIVE AND CLUTCH:

This subclass is indented under the class definition. Apparatus comprising the combination of a clutch under the ... and a device described in (1) Note below as a "Vortex-Flow Drive".

(1) Note. For the purposes of this subclass (3.21) and subclass 3.34 below, a "Vortex-Flow Drive" is defined as a device for transmitting torque from a first, rotating shaft to a second, coaxial rotatable shaft, to which shafts are secured shroud elements, each of which is generally concave (e.g., hemispherical or hemitoroidal) and provided with generally radial vanes secured within the concavity, the elements being capable of rotation relative to one another, but together forming a spheroidal or toroidal enclosure for a mass of liquid material, in which device rotation of the first shaft (and of the vanes carried thereby) causes particles of the liquid mass to circulate in a small circle that lies in a plane coincident with (or parallel to) the axis of rotation of the shafts and simultaneously circulate in a larger circle that lies in a plane at right angles to said axis, which circulation of the mass causes rotation of the second shaft as the vanes carried thereby are moved by the fluid.

(2) Note. The device termed herein "Vortex-Flow Drive", is known in the art by such names as "fluid drive", "fluid coupling", "fluid flywheel", "torque converter", and "hydrokinetic torque transformer", among others. Such devices generally fall into one of two categories. In one of these (e.g, "fluid coupling") the angular velocity of the driven shroud element referred to in (1) Note cannot be greater than that of the driving element (and is usually less due to slippage); thus the torque is not increased. In the other category (e.g., "torque converter") an additional, radially-vaned element is interposed in the flow of fluid to modify direction of movement and velocity in the fluid and thereby change the torque transmitted from the first shaft to the second shaft.

(3) Note. A combination of vortex-flow drive and clutch which, per se, is classified in this subclasses (3.21+) is properly classified in Class 74 or Class 475 if gearing is also recited in the claims.

SEE OR SEARCH THIS CLASS, SUBCLASS:

57,	for an assemblage of mechanical and fluent material clutches.

SEE OR SEARCH CLASS:

60,	Power Plants, subclasses 330+ for a "vortex-flow drive" device, per se.
74,	Machine Element or Mechanism, subclass 730 for the combination of vortex-flow drive and gearing; and see (3) Note above.
475,	Planetary Gear Transmission Systems or Components, subclasses 31+ , for fluid drive and control in planetary gear transmission; and see (3) Note above.

[List of Patents for class 192 subclass 3.22]

3.22

With means to effect torque reversal:

This subclass is indented under subclass 3.21. Device including a rotated input shaft that drives the combination (i.e., the vortex-flow drive plus the clutch), and a rotatable output shaft which may be driven by said combination in a first direction of rotation, and provided with means to change the direction of rotation of said output shaft while the input shaft continues to rotate in its original direction.

(1) Note. The shafts referred to in the definition above are not necessarily those referred to in the definition of "Vortex-Flow Drive", as found in (1) Note to the definition of subclass 3.21. If, in a particular disclosure, a shaft serves both as an "input" or "output" shaft as defined in this subclass (3.22) and as a shaft defined in subclass 3.21, such occurrence is coincident rather than significant.

(2) Note. The "means" referred to above may comprise a second clutch, or a brake, or structure to reverse the flow of fluid within the vortex-flow drive.

SEE OR SEARCH CLASS:

74,	Machine Element or Mechanism, subclasses 730.1+ for torque reversal means inherent in a combination of fluid drive and gearing.
475,	Planetary Gear Transmission Systems or Components, subclasses 31+ , for fluid drive and control in planetary gear transmission.

[List of Patents for class 192 subclass 3.23]

3.23

With brake:

This subclass is indented under subclass 3.21. Device further provided with a brake.

(2) Note. For a line between Classes 188 and 192 with respect to a patent to a vortex-flow drive plus a brake, without a clutch, see (2) Note to subclass 3.34 below.

[List of Patents for class 192 subclass 3.24]

3.24

Alternatively operative clutch and brake:

This subclass is indented under subclass 3.23. Device wherein either the clutch or the brake (but not both simultaneously) is in functioning relationship.

(1) Note. For the purposes of this subclass (3.24) a clutch is "functioning" when it is effective to transmit force, and a brake is "functioning" when it is effective to retard motion.

3.25	With additional drive or clutch:
	This subclass is indented under subclass 3.21. Device including at least two "Vortex-Flow Drives", or at least two clutches.

3.26	Simultaneously operative clutches:
	This subclass is indented under subclass 3.25. Device including at least two clutches that are in force-transmitting, relationship at the same time.

[List of Patents for class 192 subclass 3.27]

3.27

Alternatively operative clutches:

This subclass is indented under subclass 3.25. Device including two clutches wherein either a first or a second of the clutches (but not both simultaneously) is in force-transmitting relationship.

(1) Note. The patents in this subclass usually disclose only two clutches in combination with a vortex-flow drive. A patent claiming a vortex-flow drive and only two clutches that are alternatively operable is proper as an original patent for this subclass even though it may disclose more than two clutches.

3.28	Including drive-lockup clutch:
	This subclass is indented under subclass 3.21. Device wherein engagement of the clutch causes the first, rotating shaft and the second, rotated shaft of the vortex-flow drive to be effectively secured together so that all rotation of the first shaft is transmitted to the second shaft in 1:1 ratio.

[List of Patents for class 192 subclass 3.29]

3.29

Having fluid-pressure operator:

This subclass is indented under subclass 3.28. Device provided with means for causing engagement and disengagement of the drive-lockup clutch, which means is actuated by force applied via a liquid or gaseous medium.

(1) Note. The fluid pressure that actuates the clutch-operator means may be derived from the toroidal flow of the vortex-flow drive or may be derived from a secondary source of fluid pressure as in subclass 3.3 hereunder.

SEE OR SEARCH THIS CLASS, SUBCLASS:

3.33,	for a fluid-pressure operator to engage a clutch other than a drive-lockup clutch) that is combined with a vortex-flow drive.
48.601+,	and 85.01+, for a fluid pressure operated clutch.

3.3	With auxiliary source of pressure:
	This subclass is indented under subclass 3.29. Combination provided with means, other than the vortex-flow drive, that generates the force in the medium.

[List of Patents for class 192 subclass 3.31]

3.31

Having speed-responsive operator:

This subclass is indented under subclass 3.28. Device provided with means for causing engagement and disengagement of the clutch and wherein the means is actuated upon the attainment of a predetermined angular velocity of one of the shafts of the vortex-flow drive.

SEE OR SEARCH THIS CLASS, SUBCLASS:

3.33,

for a fluid-pressure operator which may be inherently speed-responsive, and see (1) Note there.

3.32	Alternatively operative drive and clutch:
	This subclass is indented under subclass 3.21. Device wherein either the vortex-flow drive or the clutch (but not both simultaneously is in force-transmitting relationship.

[List of Patents for class 192 subclass 3.33]

3.33

Fluid-pressure operator for engaging clutch:

This subclass is indented under subclass 3.21. Device provided with means for causing engagement of the clutch, which means is actuated by force applied via a liquid or gaseous medium.

(1) Note. Many of the patents in this subclass (3.33) disclose the fluid pressure for actuating the clutch to be derived from the toroidal flow of the vortex-flow drive. It is inherent in such disclosures that the clutch engagement is speed responsive.

SEE OR SEARCH THIS CLASS, SUBCLASS:

3.29+,

for a fluid-pressure operator to actuate a vortex-flow drive-lockup clutch.

[List of Patents for class 192 subclass 3.34]

3.34

VORTEX-FLOW DRIVE AND BRAKE:

This subclass is indented under subclass 3.21. Apparatus under the class definition in which the mechanism for control of power includes a brake and a device described in (1) Note of ... of this class (192).

(1) Note. The term "brake" is intended to refer to that device classified, per se, in Class 188, Brakes. This subclass and this note are not intended to change the line between Class 188 and Class 192 involving brakes and clutches, in general. It should be further noted that Class 188 (particularly subclass 296) is the locus of patents to a "fluid brake", wherein the structure is superficially similar to a vortex-flow drive as described in (1) Note of subclass 3.21 above. However, in the disclosures found in Class 188 subclass 296, one of the elements is fixed to its supporting structure to retard rotation of the other element.

(2) Note. The line between this class (192) and Class 60, Power Plants is not intended to be changed as a result of the establishment of this subclass (3.34). This subclass (3.34) is intended as the locus of patents to a vortex-flow drive plus a brake applied to either the first or second shaft of such drive (as described in (1) Note of subclass 3.21). Class 60 particularly subclasses 330+ is intended as the locus of patents to a device similar to that described in that (1) Note, wherein a brake is applied to the additional, interposed element described in that (1) Note. (The interposed element is known in the art as a "reactor member").

SEE OR SEARCH CLASS:

60,	Power Plants, subclasses 330+ ; and see (2) Note, above.
188,	Brakes, subclass 296 ; and see (1) Note, above.

3.51	TRANSMISSION CONTROL AND CLUTCH CONTROL:
	This subclass is indented under the class definition. Device including means to determine the operational mode of a clutch structure and including means to determine the ratio of a multi-ratio motion transmitting mechanism.

3.52	Planetary transmission and coaxial clutch:
	This subclass is indented under subclass 3.51. Device wherein the multi-ratio motion transmitting mechanism controlled is of the type wherein an element called a planet member rotates about an axis, which axis revolves about a second axis, in which the rotation and the revolution may or not be simultaneous; and wherein the clutch structure controlled is functional to transmit motion directly and by-pass the multi-ratio motion transmitting mechanisms.

3.53	Including separate, reversing pedal:
	This subclass is indented under subclass 3.52. Device including means adapted to be engaged by the foot of an operative to determine the output of the transmission to rotate oppositely to the input.

[List of Patents for class 192 subclass 3.54]

3.54

Common control:

This subclass is indented under subclass 3.51. Device wherein the means used to determine the operational mode of the clutch is also used to determine the ratio of the transmission.

SEE OR SEARCH THIS CLASS, SUBCLASS:

3.63,

for structure including a clutch control and a transmission control interrelated so that one must be in a prescribed position before the other will function.

3.55	Power-operated clutch:
	This subclass is indented under subclass 3.54. Device wherein a clutch member is moved relative to a cooperating member into or out of motion transmitting engagement therewith by energy originating at a source other than an operative.

3.56	Electromagnetically operated:
	This subclass is indented under subclass 3.55. Device wherein the clutch member is moved relative to the cooperating member by the attracting force of an electrically induced magnetic field in one member acting on ferrous-like material in the other member (or on structure connected to the members).

3.57	Fluid-press operated:
	This subclass is indented under subclass 3.55. Device wherein the clutch member is moved relative to the cooperating member by the action of a pressurized flowable medium acting on one of the members (or on structure connected thereto).

3.58	Electrically triggered:
	Device under 3.57 including structure for conducting electrical current which is regulated responsive to the mode/ratio determining means to, in turn, regulate the flow of the clutch operating medium.

3.59	Vacuum operated:
	This subclass is indented under subclass 3.57. Device including provision to reduce the pressure on a portion of one of the members (or structure connected thereto) so that atmospheric pressure serves to moves that member relatively to the other member.

3.61	Stepped ratio transmission:
	This subclass is indented under subclass 3.54. Device wherein the multi-ratio motion transmitting mechanism is of a type capable of operation in a limited number of specific, exactly proportional relationships.

3.62	With control lever:
	This subclass is indented under subclass 3.61. Device wherein the common control includes means adapted to be gripped by the hand of an operator.

3.63	Interrelated (e.g., with interlock):
	This subclass is indented under subclass 3.51. Device wherein the operation of one of the control means is dependent on the operational characteristics of the other control means.

[List of Patents for class 192 subclass 12]

CLUTCH AND BRAKE:

This subclass is indented under the class definition. Mechanism in which a clutch or brake is applied alternately to drive and retard or stop the mechanism.

SEE OR SEARCH THIS CLASS, SUBCLASS:

223.1,

through 223.4, where the brake is applied automati-cally on the breaking of a belt.

SEE OR SEARCH CLASS:

188,

Brakes, subclass 291 for a fluid-resistance brake having a clutch between the brake and a rotating load to connect and disconnect the brake from the load.

254,

Implements or Apparatus for Applying Pushing or Pulling Force, subclasses 300 , 318, 347, and 366 for apparatus for hauling or hoisting a load, including at least one cable-pulling drum which is driven around its rotational axis by a drive having a clutch mechanism with coaxial, rotatable, relatively shiftable axially, power-transmitting components; the clutch mechanism is linked to and is operationally influenced by a frictional brake assembly which retards the rotation of the drum.

13	Vehicle type:
	This subclass is indented under subclass 12. Combinations of clutch and brake adapted for use in propelling and retarding vehicles.

[List of Patents for class 192 subclass 14]

Same member:

This subclass is indented under subclass 12. Combinations in which the clutch and brake are the same member.

SEE OR SEARCH THIS CLASS, SUBCLASS:

16,	for brakes which are automatically applied when drive through the clutch ceases.

15	Automatic check and release:
	This subclass is indented under subclass 12. Combinations in which the brake is applied automatically when drive through the clutch ceases.

16	Clutch and brake same member:
	This subclass is indented under subclass 15. Combinations in which the clutch and brake are the same member.

17	Peripheral brake:
	This subclass is indented under subclass 12. Combinations in which the brake is applied transversely to the periphery of a wheel.

18	Sliding operation:
	This subclass is indented under subclass 12. Combinations in which both the clutch and brake move parallel to the axis of motion.

[List of Patents for class 192 subclass 19]

Crank control:

This subclass is indented under subclass 12. Combinations in which the clutch and brake are operated by the crank that drives the shaft.

SEE OR SEARCH THIS CLASS, SUBCLASS:

100,	for follow up type clutch operators.

20	CLUTCH AND GEAR:
	This subclass is indented under the class definition. Clutches in which the clutch is associated with a gear that is instrumental simply in completing the operation of the clutch.

21	Reversing:
	This subclass is indented under subclass 20. Clutches in which the gearing completes the reversal of the clutch.

[List of Patents for class 192 subclass 21.5]

21.5

FIELD RESPONSIVE FRICTIONAL MEDIA TYPE:

This subclass is indented under the class definition. Devices wherein torque is transmitted or absorbed between two relatively movable members having a medium there between and wherein the frictional characteristics of the medium are (1) augmented by, or (2) altered in response to a change in, a magnetic or an electrostatic field set up between the two members.

SEE OR SEARCH THIS CLASS, SUBCLASS:

84.1+,

for other types of electrically actuated clutches.

SEE OR SEARCH CLASS:

310,	Electrical Generator or Motor Structure, subclasses 92+ for electrodynamic torque transmitting clutches or brakes.

22	LATCH OPERATED:
	This subclass is indented under the class definition. Clutches in which the operation of a clutching or transmission member is accomplished through a latch or relatively stationary finger.

23	Corn-planter type:
	This subclass is indented under subclass 22. Clutches peculiarly adapted to seed-planters.

24	Longitudinally moving transmission member:
	This subclass is indented under subclass 22. Clutches in which a clutching member moves parallel to the axis of rotation.

[List of Patents for class 192 subclass 25]

Pin:

This subclass is indented under subclass 24. Mechanism in which the clutching member is a pin.

SEE OR SEARCH CLASS:

26,	Textiles: Cloth Finishing, subclass 24 for clutches associated with cloth pulling machines.

26	Transversely moving transmission member:
	This subclass is indented under subclass 22. Clutches in which the clutching member moves transversely to the axis of rotation.

[List of Patents for class 192 subclass 27]

Ball or roller:

This subclass is indented under subclass 26. Clutches in which the active element of the latch-operated mechanism is a ball or roller.

SEE OR SEARCH THIS CLASS, SUBCLASS:

45,	for ball and roller one-way engaging automatic clutches and see the notes thereto for other ball and roller clutches.

28	Positive:
	This subclass is indented under subclass 26. Clutches in which the transversely-moving clutching member engages positively.

29	Rotating key:
	This subclass is indented under subclass 28. Clutches in which the positive clutching member is a rotary approximately cylindrical member.

[List of Patents for class 192 subclass 30]

CLUTCHES:

This subclass is indented under the class definition. A power-transmitting device utilizing friction or interlocking parts for securing and releasing driving continuity as between two shafts or a pulley and a shaft or other driving and driven parts.

(1) Note. Class 464, in subclasses 30+, has overload release couplings wherein relative rotation between coupled members continues so long as an overload condition occurs. The line between Class 464, subclasses 30+, and Class 192, subclasses 56.1+, is that Class 464 takes structure wherein relatively rotatable surfaces move with respect to each other during an overload condition; but drive through such surfaces is automatically reestablished, without an additional operation, upon correction of the overload condition. Class 192, subclasses 56.1+, requires a further operation, in addition to correcting the overload condition, to reestablish the drive; such further operation being, for example, operator assisted reengagement or reduction in rotational speed of a power input member.

SEE OR SEARCH THIS CLASS, SUBCLASS:

3.21+,

for a vortex-flow drive and clutch, and especially subclasses 3.28+ for a drive-lockup clutch.

SEE OR SEARCH CLASS:

91,	Motors: Expansible Chamber Type, subclass 55 for a significantly claimed expansible chamber motor combined with a clutch in the output therefrom and not involving an interrelated control of the motor and clutch.
166,	Wells, subclasses 237+ for well devices with clutches.
464,	Rotary Shafts, Gudgeons, Housings, and Flexible Couplings for Rotary Shafts, subclasses 30+ for overload release coupling devices in accordance with the aforementioned line note.

[List of Patents for class 192 subclass 31]

Automatic:

This subclass is indented under subclass 30. Clutches which engage without manipulation upon the initiation of rotation of the parts to which they are attached.

SEE OR SEARCH CLASS:

180,	Motor Vehicles, subclasses 14.1+ for clutch operations due to unusual motions of automobile tractors.

[List of Patents for class 192 subclass 32]

Manual control:

This subclass is indented under subclass 31. Clutches the action of which is initiated by manipulation, upon which the engagement is completed automatically.

SEE OR SEARCH THIS CLASS, SUBCLASS:

47,	for one-way engaging automatic clutches that may be made operative or inoperative by manipulation.

SEE OR SEARCH CLASS:

188,	Brakes, subclasses 82.3+ for one-way brakes which include means whereby the brake may be rendered inoperative to prevent retrograde motion of a rotating element.

33	Definite-position release:
	This subclass is indented under subclass 32. Clutches in which the clutch is disengaged at the end of a cycle.

34	Shaft thrust:
	This subclass is indented under subclass 32. Clutches in which the action of engagement is completed by the thrust of the shaft.

35	Pilot mechanism:
	This subclass is indented under subclass 32. Clutches in which the initial action is to throw in a pilot-clutch or other pilot mechanism, which operates to effect the engagement of the main clutch.

36	Brake band:
	This subclass is indented under subclass 35. Clutches in which the pilot mechanism is of a brake-band type.

37	Transversely moving:
	This subclass is indented under subclass 32. Clutches in which the clutching parts move transversely to the axis of rotation.

[List of Patents for class 192 subclass 38]

Ball or roller:

This subclass is indented under subclass 37. Clutches in which the transversely-moving clutching part is a ball or roller.

SEE OR SEARCH THIS CLASS, SUBCLASS:

45,	for one-way engaging automatic clutches in which the engaging element is a ball or roller and see the notes thereto for other ball or roller clutches.

39	Positive:
	This subclass is indented under subclass 37. Clutches in which the transversely-moving clutching parts are positively engaged.

40	Electric:
	This subclass is indented under subclass 32. Clutches in which the automatic action of the clutch is controlled electrically.

[List of Patents for class 192 subclass 41]

One-way engaging:

This subclass is indented under subclass 31. Clutches which engage in one direction of rotation without manipulation.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.6,

and 48.92, for plural clutch-assemblages including a one-way engaging clutch.

SEE OR SEARCH CLASS:

74,	Machine Element or Mechanism, subclasses 111+ for mechanical movements, intermittent grip type, especially subclasses 144+, for lever mounted grip units, and see (1) Note to the definition of Class 74, and subclass 144 for the line between these two subclasses.
123,	Internal-Combustion Engines, subclasses 185.1+ for internal combustion engine cranking mechanisms.
188,	Brakes, subclasses 82.1+ , for brakes applied to elements rotating relative to stationary elements to prevent retrograde rotation while allowing forward rotation.

[List of Patents for class 192 subclass 42]

Free-engine type:

This subclass is indented under subclass 41. Clutches designed to impart initial movement to an engine to start the same, the clutch releasing when the speed of the engine exceeds the starting-speed.

SEE OR SEARCH THIS CLASS, SUBCLASS:

63,	for manually-controlled clutches of this type.

[List of Patents for class 192 subclass 43]

Reversible:

This subclass is indented under subclass 41. Clutches adjustable to drive in either direction.

SEE OR SEARCH CLASS:

188,	Brakes, subclass 82.2 for one-way brakes in which the direction in which retrograde rotation is prevented is selectable.

[List of Patents for class 192 subclass 43.1]

43.1

Pivoted pawls:

This subclass is indented under subclass 43. Clutches in which the engaging elements are pivoted pawls, each set of pawls comprising a pair of oppositely-directed pivoted pawls, which may be an integral single member.

SEE OR SEARCH CLASS:

81,	Tools, subclasses 29+ for ratchet type bit stocks.
188,	Brakes, subclasses 82.7+ for one-way brakes in which there is a pivoting or flexing detent.

[List of Patents for class 192 subclass 43.2]

43.2

Slidable pawls:

This subclass is indented under subclass 43. Clutches in which the engaging elements are slidable pawls.

SEE OR SEARCH CLASS:

81,	Tools, subclasses 29+ , for ratchet type bit stocks.

[List of Patents for class 192 subclass 44]

Ball or roller:

This subclass is indented under subclass 43. Clutches in which the engaging elements are balls or rollers.

SEE OR SEARCH THIS CLASS, SUBCLASS:

45,	for ball or roller one-way engaging clutches and see the notes thereto for other clutches with a ball or roller engaging element.

[List of Patents for class 192 subclass 45]

Ball or roller:

This subclass is indented under subclass 41. Clutches in which the engaging element is a ball or roller.

SEE OR SEARCH THIS CLASS, SUBCLASS:

27,	for latch operated clutches in which the transmitting member is a ball or roller.
38,	for one-way automatic manually controlled clutches in which the clutching element is a ball or roller.
44,	for one-way clutches in which the clutching element is a ball or roller.

SEE OR SEARCH CLASS:

74,	Machine Element or Mechanism, subclasses 162+ for intermittent grip devices.
188,	Brakes, subclass 82.84 , for one-way brakes in which the engaging element rolls into jamming position between converging surfaces one of which is the rotating element to exert a braking force.

[List of Patents for class 192 subclass 45.1]

45.1

Wedging pawl or block:

This subclass is indented under subclass 41. Clutches in which the engaging element is a wedging pawl or block.

SEE OR SEARCH CLASS:

188,	Brakes, subclasses 82.7+ for one-way brakes employing a pivoting or flexing detent, and subclasses 82.8+ for one-way brakes in which retrograde rotation of a rotating element forces a member in jamming position between converging surfaces one of which is the rotating element to cause a braking.

45.2	Two-point gripper:
	This subclass is indented under subclass 41. Clutches in which the engaging element has a two-point frictional gripping contact.

[List of Patents for class 192 subclass 46]

Positive:

This subclass is indented under subclass 41. Clutches which positively engage.

SEE OR SEARCH CLASS:

74,	Machine Element or Mechanism, subclasses 111+ for mechanical movements, intermittent grip type.

[List of Patents for class 192 subclass 47]

Manual control:

This subclass is indented under subclass 41. Clutches that may be made operative or inoperative by manipulation.

SEE OR SEARCH THIS CLASS, SUBCLASS:

32+,	for automatic clutches in which the action is initiated by manipulation upon which the engagement is completed automatically.

SEE OR SEARCH CLASS:

188,	Brakes, subclass 82.3 for one-way brakes with means by which it may be rendered inoperative to prevent retrograde motion of rotating element.

[List of Patents for class 192 subclass 48.1]

48.1

Plural clutch-assemblages:

This subclass is indented under subclass 30. Mechanism provided with at least two clutch-assemblages associated together to transmit rotation from at least one rotating input shaft to at least one rotatable output shaft.

(1) Note. A clutch-assemblage comprises all the parts that cooperate together to (a) connect a rotating "input" shaft (or a pulley, drum, flywheel, gear or other equivalent torque-transmitting member) to a rotatable "output" shaft (or hub, pulley, gear or other equivalent torque-transmitting member) that is coaxial with and driven by the input shaft, or (b) disconnect said shafts from rotational relationship, either action being performed at the will of the user of the clutch-assemblage. Although any clutch-assemblage is by itself a distinct entity and is capable of transmitting rotation from an input shaft to an output shaft, different clutch-assemblages may have parts in common. That is, a part may form one of the components of a first clutch-assemblage at one time, and that part may also form one of the components of a second clutch-assemblage at another time. An example of a use for such an arrangement is a machine having an input shaft that may be clutched selectively to any of a plurality of output shafts by using a shiftable clutch-element first in one clutch-assemblage and then in another clutch-assemblage. See subclass 48.91 for such an arrangement. Another common arrangement is a first clutch-assemblage having an output shaft that is also the input shaft of a second clutch-assemblage in "series" relationship.

(2) Note. The term "clutch-element" as used in this and indented subclasses has the same meaning as the term defined and described in the definition and notes of subclass 70.11 below. However, whereas in subclass 70.11 the engaging surface is usually a friction surface, in this subclasses (48.1+) it may be a friction surface or a toothed or gear-like surface or any other surface configuration that will mate with another, complementary surface on a second clutch-element to transmit rotation between the elements having such surfaces.

SEE OR SEARCH THIS CLASS, SUBCLASS:

3.26,	for a combination including a vortex-flow drive and a plurality of clutches.
35+,	for a multiple-clutch arrangement in which one clutch serves as a pilot operator for the other.
57,	for a combination of fluent-material clutch and mechanical clutch.

[List of Patents for class 192 subclass 48.2]

48.2

Including electrically actuated clutch assemblage:

This subclass is indented under subclass 48.1. Device wherein one of the associated clutch-assemblages is provided with clutch-elements that are mutually engaged or disengaged by electromagnetic energy.

(1) Note. Included in the subclass are plural clutch-assemblages of which at least one is actuated by eddy currents, or by a field-responsive frictional medium, (per se, classified in subclass 21.5) or by an electrical operator, (per se, classified in subclasses 84.1+).

SEE OR SEARCH THIS CLASS, SUBCLASS:

21.5,

and 84.1+, and see (1) Note above.

SEE OR SEARCH CLASS:

310,	Electrical Generator or Motor Structure, subclasses 92+ , for an eddy current clutch associated with other structure provided for in that schedule.

[List of Patents for class 192 subclass 48.3]

48.3

Diverse clutch-assemblages:

This subclass is indented under subclass 48.1. Device wherein one of the associated clutch-assemblages is different in its principle of operation from another.

(1) Note. Examples of arrangements wherein the principle of operation is "different" include: Arrangements wherein one clutch-assemblage is actuated by fluid pressure whereas another clutch-assemblage is actuated by mechanical linkage; arrangements wherein one clutch-assemblage uses clutch-elements that engage positively, as by splines, intermeshing teeth or ratchet-and-pawl elements, whereas another clutch-assemblage uses clutch-elements that engage frictionally, as by surface-to-surface contact; and arrangements wherein one clutch-assemblage is intended to function in only one direction of rotation whereas another clutch-assemblage is intended to transmit all torque applied thereto in either direction of rotation. Minor differences in shape or size between the elements of clutch-assemblages, not involving differences in operation, are not justification for placement into this and indented subclasses. For example, an arrangement of clutch-assemblages wherein one has tapered clutch-elements and another has disc clutch-elements or an arrangement of clutch-assemblages wherein one uses rollers and another uses balls, are not properly considered to be "diverse", but will be classified in subclasses 48.11+ according to their plural characteristics.

48.4	Including three or more assemblages:
	This subclass is indented under subclass 48.3. Device provided with more than two associated clutch-assemblages.

[List of Patents for class 192 subclass 48.5]

48.5

Including one clutch-assemblage having interdigitated clutch-elements:

This subclass is indented under subclass 48.3. Device wherein one of the associated clutch-assemblages is provided with a clutch-element that intermeshes with a mating clutch-element to transmit torque positively (i.e., without slipping), in at least one direction of rotation, from an input shaft to an output shaft.

(1) Note. The clutch-assemblage defined above is also known as a "positive" clutch. The other clutch-assemblage associated therewith in this subclass (48.5) usually has friction clutch-elements.

SEE OR SEARCH THIS CLASS, SUBCLASS:

28+,	39, 46, 69+, and 71 and for a clutch, per se, of "positive" type.

[List of Patents for class 192 subclass 48.6]

48.6

And another clutch-assemblage having unirotationally engaging clutch elements:

This subclass is indented under subclass 48.5. Device wherein a second one of the associated clutch-assemblages is provided with clutch-elements that transmit torque from an input shaft to an output shaft in only one direction of rotation of the input shaft, which clutch-elements permit rotation in said direction of the output shaft relative to the input shaft.

(1) Note. The clutch-assemblage herein is also known by the terms "Overrunning clutch", "One-way clutch" and "Free-wheeling clutch". The purpose of such arrangement is to cause engagement of the clutch-elements when the input shaft is powered whereby the output shaft will rotate at least as fast as the input shaft, but to permit the output shaft to rotate faster than the input shaft under certain conditions of operation.

(2) Note. This subclass provides for two or more clutch-assemblages, one of which has positively-engaging clutch-elements and another of which has one-way-engaging clutch-elements.

SEE OR SEARCH THIS CLASS, SUBCLASS:

41+,	for a one-way-engaging clutch.
48.92,	for plurality of one-way-engaging clutch-assemblages.

48.601

Having fluid pressure operator:

This subclass is indented under subclass 48.1. Subject matter in which the clutch-assemblages include a clutch-assemblage that is actuated (i.e., caused to engage or disengage) by the action of fluid under pressure.

(1) Note. The phrase "action of fluid under pressure" is intended to include the effects of fluid whose pressure is less than ambient or atmospheric pressure and typically referred to as "vacuum" or "partial vacuum".

SEE OR SEARCH THIS CLASS, SUBCLASS:

3.25+,	for a combination of vortex-flow drive and a plurality of clutches, wherein the clutches may be fluid-pressure operated.
3.29+,	and 3.33, for a fluid-pressure operator for a clutch that is combined with a vortex-flow drive.
48.1+,	for a combination of multiple clutches that are mechanically operated.
85.01+,	for a clutch having a fluid-pressure operator.

SEE OR SEARCH CLASS:

92,	Expansible Chamber Devices, appropriate subclassesfor an expansible chamber device, per se, even though disclosed as a means to operate a clutch.
303,	Fluid-Pressure and Analogous Brake Systems, appropriate subclassesfor systems of distribution of fluid to motors of more general application.

48.602	Operator rotatable relative to its clutch-assemblage:
	This subclass is indented under subclass 48.601. Subject matter in which the fluid under pressure acts through a fluid motor that is rotatable relative to both the driving and driven parts connected by the fluid-operated clutch-assemblage.

48.603

Operator coaxial with its clutch-assemblage:

This subclass is indented under subclass 48.602. Subject matter in which an axis along which the fluid motor acts is aligned with an axis of rotation of the fluid-operated clutch-assemblage.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.611+,

48.617, and 48.618+, for a clutch and coaxial actuator that may rotate with the clutch.

48.604

Common or interconnected operator(s):

This subclass is indented under subclass 48.603. Subject matter in which the fluid motor contributes to operation (engagement or disengagement) of two or more of the clutch-assemblages or in which the fluid motor and an additional fluid motor operate two or more of the clutch-assemblages and the position of an output element (e.g., piston, actuating shaft) of one of the fluid motors is dependent upon the position of an output element the other fluid motor.

SEE OR SEARCH THIS CLASS, SUBCLASS:

3.27,	for the combination of a vortex-flow drive and alternatively operative clutches that may include a common actuator or interconnected actuators.
48.612+,	for common or interconnected actuator(s) that may rotate with associated clutches.

48.605

Operator between clutch-assemblages:

This subclass is indented under subclass 48.604. Subject matter in which the fluid motor is located between two of the clutch-assemblages.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.613,

and 48.614, for clutches and an actuator that may rotate relative to at least one of the clutches and that is located between the clutches.

48.606

Axially spaced coaxial clutch-assemblages:

This subclass is indented under subclass 48.603. Subject matter in which two of the clutch-assemblages rotate about a common axis and have disengageable power-transmitting portions (e.g., friction surfaces), all disengageable power-transmitting portions of one of the two clutch-assemblages being axially spaced at all times from all disengageable power-transmitting portions of the other clutch-assemblage.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.607,

and 48.609+, for other axially spaced coaxial clutches.

48.607

Axially spaced coaxial clutch-assemblages:

This subclass is indented under subclass 48.602. Subject matter in which two of the clutch-assemblages rotate about a common axis and have disengageable power-transmitting portions (e.g., friction surfaces), all disengageable power-transmitting portions of one of the two clutch-assemblages being axially spaced at all times from all disengageable power-transmitting portions of the other clutch-assemblage.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.606,

and 48.609+, for other axially spaced coaxial clutches.

48.608

Plural fluid pressure operators forming nested pistons:

This subclass is indented under subclass 48.602. Subject matter in which the fluid pressure also acts through an additional fluid motor, each fluid motor having a piston movable by application of the fluid pressure thereto, the piston of one of the fluid motors forming a cylinder of the other fluid motor in which cylinder the piston of the other fluid motor is movable.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.61,

and 48.616+, for other clutches having actuators forming nested pistons.

48.609

Axially spaced coaxial clutch-assemblages:

This subclass is indented under subclass 48.601. Subject matter in which two of the clutch-assemblages rotate about a common axis and have disengageable power-transmitting portions (e.g., friction surfaces), all disengageable power-transmitting portions of one of the two clutch-assemblages being axially spaced at all times from all disengageable power-transmitting portions of the other of the two clutch-assemblages.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.606,

and 48.607, for other axially spaced coaxial clutches.

48.61

Plural fluid pressure operators forming nested pistons:

This subclass is indented under subclass 48.609. Subject matter including two fluid motors that actuate one or more of the clutch assemblages, each fluid motor having a piston movable by application of the fluid pressure thereto, the piston of one of the fluid motors forming a cylinder of the other fluid motor in which cylinder the piston of the other fluid motor is movable.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.608,

and 48.616+, for other clutches having actuators forming nested pistons.

48.611

Operator coaxial with its clutch-assemblage:

This subclass is indented under subclass 48.609. Subject matter in which the fluid under pressure acts through a fluid motor and an axis along which the fluid motor acts is aligned with an axis of rotation of the fluid actuated clutch-assemblage.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.603+,

48.617, and 48.618+, for a clutch and coaxial actuator.

48.612

Common or interconnected operator(s):

This subclass is indented under subclass 48.611. Subject matter in which the fluid motor contributes to operation (engagement or disengagement) of two of the clutch-assemblages or in which the fluid motor and an additional fluid motor operate two of the clutch-assemblages and the position of an output element (e.g., piston, actuating shaft) of one of the fluid motors is dependent upon the position of an output element the other fluid motor.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.604+,	for common or interconnected actuator(s) that rotate relative to associated clutch(es).
3.27,	for the combination of a vortex-flow drive and alternatively operative clutches that may include a common or interconnected actuator(s).

48.613

Operator between clutch-assemblages:

This subclass is indented under subclass 48.612. Subject matter in which the fluid motor is located between the two clutch-assemblages.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.605,

and 48.614, for plural clutches and an actuator located between the clutches.

48.614

Operator between clutch-assemblages:

This subclass is indented under subclass 48.611. Subject matter in which the fluid motor is located between two of the clutch-assemblages.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.605,

and 48.613, for other actuators located between clutches.

48.615

Radially acting operator:

This subclass is indented under subclass 48.609. Subject matter in which the fluid under pressure acts through a fluid motor and an axis along which the fluid motor acts is substantially perpendicular to the axis of rotation of the fluid actuated clutch-assemblage.

SEE OR SEARCH THIS CLASS, SUBCLASS:

85.12+,

85.16, and 85.47, for a clutch operated by a radially acting fluid pressure actuator.

48.616

Plural fluid pressure operators forming nested pistons:

This subclass is indented under subclass 48.601. Subject matter in which the fluid under pressure acts through two fluid motors that actuate one or more of the clutch assemblages, each fluid motor having a piston movable by application of the fluid pressure thereto, the piston of one of the fluid motors forming a cylinder of the other fluid motor in which cylinder the piston of the other fluid motor is movable.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.608,

and 48.61, for clutch actuators forming nested pistons.

48.617

At least one operator coaxial with its clutch-assemblage:

This subclass is indented under subclass 48.616. Subject matter in which at least one of the fluid motors acts along an axis that is aligned with an axis of rotation of (one of) the clutch-assemblage(s) it actuates.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.603+,

48.611+, and 48.618+, for a clutch and coaxial actuator.

48.618

Operator coaxial with its clutch-assemblage:

This subclass is indented under subclass 48.601. Subject matter in which the fluid under pressure acts through a fluid motor to actuate the clutch-assemblage and an axis along which the fluid motor acts is aligned with an axis of rotation of the clutch-assemblage.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.603+,

48.611+, and 48.617, for a clutch and coaxial actuator.

48.619	Radially spaced coaxial clutch-assemblages:
	This subclass is indented under subclass 48.618. Subject matter in which the clutch-assemblages include two clutch-assemblages having the same axis of rotation and having disengageable power-transmitting portions (e.g., friction surfaces), the clutch-assemblages being arranged such that a plane perpendicular to the axis of rotation passes through or between at least one disengageable power-transmitting portion of each of the two clutch-assemblages.

[List of Patents for class 192 subclass 48.7]

48.7

With means to actuate or deactuate clutch-assemblages sequentially:

This subclass is indented under subclass 48.1. Device wherein two or more clutch-assemblages are intended to be operative simultaneously as a set, provided with means to ensure that one clutch-assemblage of said set has its clutch-elements fully engaged before another clutch-assemblage of said set has its clutch-elements engaged, or with means to ensure that one clutch-assemblage of said set has its clutch-elements fully disengaged before another clutch-assemblage of said set has its clutch-elements disengaged.

(1) Note. The set of clutch-assemblages described above permits torque from an input shaft to be applied to an output shaft in stages, or progressively, in order to reduce stress or shock attendant upon a sudden application of load.

SEE OR SEARCH THIS CLASS, SUBCLASS:

52.1+,

and 70.21, for other arrangements for progressively transmitting load from an input to an output shaft.

[List of Patents for class 192 subclass 48.8]

48.8

Associated with three or more shafts:

This subclass is indented under subclass 48.1. Device wherein the clutch-assemblages are provided with more than two shafts for input or output of torque, in any combination of one (or more) input shaft (s) plus two (or more) output shafts, or of two (or more) output shafts plus one (or more) output shaft (s).

(1) Note. For the purposes of this and indented subclasses, a shaft is a rotating member that transmits torque; thus a gear, pulley, drum, hub, etc., is equivalent to a shaft. An input shaft is such a member that is rotated by a source of power external to the device, and an output shaft is such a member that (a) is rotated by the claimed device AND (b) rotates a torque-using mechanism external to the claimed device. Thus, if there are rotating members that transmit torque between the input and output shafts within the device they are not counted in the number "three or more" required for these subclasses.

[List of Patents for class 192 subclass 48.9]

48.9

Alternatively operative assemblages:

This subclass is indented under subclass 48.8. Device wherein either a first or a second of the clutch-assemblages (but not both simultaneously) is in torque-transmitting relationship.

SEE OR SEARCH THIS CLASS, SUBCLASS:

3.27,	for the combination of a vortex-flow drive and alternatively operative clutches.
48.604+,	and 48.612+, for multiple fluid clutches having a common actuator that may allow only alternate engagement of the clutches.

48.91	Having common clutch-element support:
	This subclass is indented under subclass 48.9. Device wherein a member rigidly carries one of the clutch-elements of the first clutch-assemblage and the same member rigidly carries one of the clutch-elements of the second clutch-assemblage.

48.92

Including unirotationally engaging clutch-elements:

This subclass is indented under subclass 48.1. Device wherein at least one of the associated clutch-assemblages is provided with clutch-elements that transmit torque from an input shaft to an output shaft in only one direction of rotation of the input shaft, which clutch-elements permit rotation in said direction of the output shaft relative to the input shaft.

SEE OR SEARCH THIS CLASS, SUBCLASS:

41+,	for a one-way-engaging clutch.
48.6,	for an arrangement of a one-way-engaging clutch-assemblage and a "positive" clutch-assemblage.

[List of Patents for class 192 subclass 49]

Parallel vehicle wheels:

This subclass is indented under subclass 48.1. Clutches associated to operate in connection with parallel vehicle-wheels.

SEE OR SEARCH CLASS:

280,	Land Vehicles, subclass 192 , for clutches driven by vehicle wheels and driving a winding drum used in controlling the vehicle.

50	Free wheel:
	This subclass is indented under subclass 49. Clutches associated to operate in connection with parallel vehicle-wheels, permitting either wheel to overrun.

[List of Patents for class 192 subclass 51]

Reversing:

This subclass is indented under subclass 48.1. Clutches instrumental in accomplishing the reversal of rotation.

SEE OR SEARCH THIS CLASS, SUBCLASS:

21,	for clutches associated with gearing to accomplish a reversal in rotation.

[List of Patents for class 192 subclass 52.1]

52.1

Progressive engagement:

This subclass is indented under subclass 30. Subject matter wherein means are provided specifically to cause clutch elements to engage gradually.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.7,	for an arrangement of two or more clutch-assemblages that engage (or disengage) progressively or in succession, thus transmitting (or releasing) torque progressively from an input shaft to an output shaft.
70.21,	for a multiple-element clutch wherein the elements engage (or disengage) sequentially.

52.2	Surface area:
	This subclass is indented under subclass 52.1. Subject matter wherein the amount of surface area of one clutch element in engagement with a second clutch element increases as the elements move toward full engagement.

52.3	Yielding:
	This subclass is indented under subclass 52.2. Subject matter wherein at least one clutch element deforms as a result of engagement to cause an increase in the engaging surface area.

52.4	Variable force:
	This subclass is indented under subclass 52.1. Subject matter wherein an engaging force is changed during clutch engagement in order to provide gradual engagement of the clutch.

52.5	Initial engagement causes increase in applied force:
	This subclass is indented under subclass 52.4. Subject matter wherein initial clutch engagement causes relative rotation of a mechanism to increase the applied force.

[List of Patents for class 192 subclass 52.6]

52.6

Yielding:

This subclass is indented under subclass 52.1. Subject matter wherein at least one clutch element deforms as a result of engagement to cause gradual engagement while the contacting surface area remains constant.

SEE OR SEARCH THIS CLASS, SUBCLASS:

107,	for a subcombination of a clutch which is axially compressible.

[List of Patents for class 192 subclass 53.1]

53.1

Frictional and positive:

This subclass is indented under subclass 52.1. Subject matter wherein after a preliminary slipping engagement of friction elements, positive clutch elements intermesh to transmit torque without slip.

SEE OR SEARCH CLASS:

188,	Brakes, subclass 68 , for similar action in brakes.

[List of Patents for class 192 subclass 53.2]

53.2

Magnetic or electromagnetic operated friction clutch:

This subclass is indented under subclass 53.1. Subject matter wherein the slipping engagement is produced by the force of a magnet or electromagnet.

SEE OR SEARCH THIS CLASS, SUBCLASS:

84+,	for clutches engaged by electromagnetic force.

[List of Patents for class 192 subclass 53.3]

53.3

With blocker:

This subclass is indented under subclass 53.1. Subject matter wherein structure is provided to resist or delay movement of a shiftable positive clutch element into full engagement to facilitate synchronization.

(1) Note. Clutches in subclasses 53.3+ are typically synchronizer clutches for use in transmissions to facilitate shifting from one gear ratio to another, and classification in these subclasses is proper even if one clutch element is claimed as a gear.

(2) Note. Where parallel transmission shafts and cooperating gears are claimed, classification in Class 74, subclasses 325+ is proper.

53.31	Self-energizing:
	This subclass is indented under subclass 53.3. Subject matter wherein a cam structure is provided to increase the clamping force of friction elements after an initial engagement of the friction elements.

53.32

Interposed friction member:

This subclass is indented under subclass 53.3. Subject matter wherein frictional engagement is provided by at least three friction elements with at least one friction element being sandwiched between adjacent elements.

(1) Note. The friction elements here are generally in the form of discs or frustocones.

SEE OR SEARCH THIS CLASS, SUBCLASS:

70.11+,

for a multiple friction element clutch assemblage, per se.

53.33	Member extending axially between friction surfaces:
	This subclass is indented under subclass 53.3. Subject matter wherein there are plural friction elements connected to at least one axially extending member which cooperates with a radially extending portion of a shift sleeve to perform a blocking function.

53.331	Blocker on axially extending stepped pin:
	This subclass is indented under subclass 53.33. Subject matter wherein at least one axially extending member has a substantially circular cross-section and the cross-section has a diameter that varies along the length of the axially extending member.

53.332

Resilient detent pin:

This subclass is indented under subclass 53.331. Subject matter further including at least one axially extending resilient member offset circumferentially from the stepped pin to cooperate with an opening in the shift sleeve to define at least one position of the shift sleeve.

(1) Note. These members are typically themselves yieldable or are made up of separate sections biased apart by a distinct resilient element.

53.34	Outward tooth or lug on friction member:
	This subclass is indented under subclass 53.3. Subject matter wherein the blocker includes at least one lug or tooth carried by a friction element in which said lug or tooth projects radially outward of the rotational axis.

53.341	With thrust member:
	This subclass is indented under subclass 53.34. Subject matter wherein the shiftable positive clutch element carries a keylike strut member for imparting axial force to the friction element.

53.342	Resilient thrust bar:
	This subclass is indented under subclass 53.341. Subject matter wherein the keylike strut member is made of a yieldable material.

53.343	Resilient expander ring:
	This subclass is indented under subclass 53.341. Subject matter wherein the keylike strut member is biased radially outward relative to the rotation axis by at least one substantially circular spring ring.

53.35	Inward tooth or lug on friction member:
	This subclass is indented under subclass 53.3. Subject matter wherein the blocker includes at least one lug or tooth carried by the friction element in which said lug or tooth projects radially toward the rotational axis.

53.36	Radially movable blocker:
	This subclass is indented under subclass 53.3. Subject matter wherein the blocker has a component of movement which is transverse or oblique to the axis of rotation to allow the shiftable positive clutch element to pass into its engaged position.

53.361	Detent acts as blocker:
	This subclass is indented under subclass 53.3. Subject matter wherein the radially movable blocker comprises structure which is provided to define a disengaged position of the shiftable positive clutch element.

53.362	Rocker lever actuates friction clutch:
	This subclass is indented under subclass 53.361. Subject matter wherein the detent is formed by or carried by a generally radially disposed pin which is pivotally mounted at its radially inner end to an input or output shaft and is releasably connected at its radially outer end to the shiftable positive clutch element; and wherein axial movement of the shiftable element causes the pin to tilt and force frictional surfaces into engagement; further shifting of the element, and engagement of the positive clutch elements, being resisted by the releasable connection until synchronization is achieved.

53.363	Radially movable friction element acts as blocker:
	This subclass is indented under subclass 53.36. Subject matter wherein one of the friction elements has a component of movement transverse to the axis of rotation to allow the shiftable positive clutch element to pass into its engaged position.

53.364	Resilient friction element:
	This subclass is indented under subclass 53.363. Subject matter wherein the transversely moving friction element is formed by a resilient ringlike member substantially concentric to the clutch rotational axis.

[List of Patents for class 192 subclass 53.4]

53.4

Lock for positive clutch:

This subclass is indented under subclass 53.1. Subject matter wherein structure is provided to prevent inadvertent disengagement of the intermeshed positive elements.

(1) Note. The structure here can be the configuration of the positive clutch teeth or a separate device to maintain the positive clutch in engagement.

SEE OR SEARCH THIS CLASS, SUBCLASS:

114+,

for element-locking means, per se.

[List of Patents for class 192 subclass 53.5]

53.5

Axially projecting positive clutch:

This subclass is indented under subclass 53.1. Subject matter wherein at least one of the positive clutch elements includes at least one tooth or lug projecting axially from an end face thereof.

(1) Note. Devices in this subclass do not include a blocker.

SEE OR SEARCH THIS CLASS, SUBCLASS:

69+,	for axially engaging positive clutches, per se.

53.51	Cylindrical pin:
	This subclass is indented under subclass 53.5. Subject matter wherein the tooth or lug has a substantially circular cross-sectional shape.

[List of Patents for class 192 subclass 53.6]

53.6

Transversely moving positive clutch:

This subclass is indented under subclass 53.1. Subject matter wherein at least one of the positive clutch elements has a component of engaging movement transverse to the axis of rotation.

(1) Note. Devices in this subclass do not include a blocker.

SEE OR SEARCH THIS CLASS, SUBCLASS:

71,	for transversely engaging clutches, per se.

[List of Patents for class 192 subclass 54.1]

54.1

Torque responsive:

This subclass is indented under subclass 30. Subject matter wherein the transmission of torque from a clutch input shaft to a clutch output shaft is affected by the torsional strain on one of the shafts.

[List of Patents for class 192 subclass 54.2]

54.2

Hub clutch:

This subclass is indented under subclass 54.1. Subject matter wherein the clutch engages a wheel hub to a selectively driven axle (e.g., in a four-wheel drive vehicle).

SEE OR SEARCH THIS CLASS, SUBCLASS:

69.4,

for positive engaging wheel hub clutches, per se.

[List of Patents for class 192 subclass 54.3]

54.3

Fluid operated:

This subclass is indented under subclass 54.1. Subject matter wherein the clutch is moved either to an engaged or disengaged position by hydraulic or pneumatic pressure.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.601+,

and 85.01+, for fluid pressure operators, per se.

[List of Patents for class 192 subclass 54.4]

54.4

Magnetic or electromagnetic:

This subclass is indented under subclass 54.1. Subject matter wherein the clutch is moved either to an engaged or disengaged position by a permanent magnet or an electromagnetic coil.

SEE OR SEARCH THIS CLASS, SUBCLASS:

84+,	for a magnetic or electromagnetic operator, per se.

[List of Patents for class 192 subclass 54.5]

54.5

Cam operated:

This subclass is indented under subclass 54.1. Subject matter wherein the torsional strain causes movement of an inclined surface relative to a cooperating structure to affect engagement of the clutch.

SEE OR SEARCH THIS CLASS, SUBCLASS:

93+,	for a cam operator, per se.

54.51	Screw operated:
	This subclass is indented under subclass 54.5. Subject matter wherein the torsional strain causes movement of a helical thread spline relative to a cooperating structure to affect engagement of the clutch.

54.52	Ball or roller type:
	This subclass is indented under subclass 54.5. Subject matter wherein the inclined surface contacts a sphere or cylinder.

[List of Patents for class 192 subclass 55.1]

55.1

With overload release coupling:

This subclass is indented under subclass 54.1. Subject matter having structure in the torque transmission path which permits continuous relative rotation between the input and output shafts, without disengaging the clutch upon occurrence of a torque overload.

(1) Note. This subclass includes the combination of a selectively engageable clutch and an overload slip coupling.

SEE OR SEARCH THIS CLASS, SUBCLASS:

52.3,	and 52.6, for clutches in which one element yields as the clutch engages to cause gradual engagement.
56.1+,	for clutches which disengage upon overload.

SEE OR SEARCH CLASS:

464,

Rotary Shafts, Gudgeons, Housings and Flexible Couplings for Rotary Shafts, subclasses 30+ , for a flexible coupling wherein means is provided for transmitting torque between input and output members so as to accommodate relative rotation between said members when resistance to rotation of said output member exceeds a predetermined value, said means including either (a) a device which is designed to rupture when said resistance to rotation exceeds said predetermined value, or (b) a device which slips or disengages when said resistance to rotation exceeds said predetermined value but which automatically reengages without operator intervention or other additional operation when said resistance to rotation no longer exceeds said predetermined value.

[List of Patents for class 192 subclass 55.2]

55.2

With flexible shaft coupling permitting limited relative rotation:

This subclass is indented under subclass 54.1. Subject matter having structure in the torque transmission path which permits limited relative rotation between the input and output shafts in order to absorb torque variations.

(1) Note. This subclass and subclasses indented thereunder include the combination of a selectively engageable clutch and a flexible shaft coupling. Classification in this subclass requires more than mere nominal recitation of a clutch.

SEE OR SEARCH THIS CLASS, SUBCLASS:

70.17,	for clutches having interposed mating clutch elements including recoilably yieldable means permitting a limited degree of variation between the rotation of a shaft and the rotation of a member supported thereby.
200+,	for a subcombination comprising a clutch element resiliently mounted on a hub.

SEE OR SEARCH CLASS:

464,	Rotary Shafts, Gudgeons, Housings and Flexible Couplings for Rotary Shafts, appropriate subclasses for flexible shaft couplings, per se.

55.3	Separate resilient member between clutch element and its shaft:
	This subclass is indented under subclass 55.2. Subject matter wherein the structure which permits limited relative rotation is a coupling separate from the engaging clutch elements and includes at least one resiliently yieldable member.

55.4	Fluid damper:
	This subclass is indented under subclass 55.3. Subject matter wherein the resilience of the resiliently yieldable member or members is provided by compressing a liquid or gas or by forcing a liquid or gas through a restriction (e.g., a dashpot).

55.5	Coil spring coaxial with rotation axis:
	This subclass is indented under subclass 55.3. Subject matter wherein at least one yieldable member is comprised of an elongated elastic element coiled about a center line which substantially coincides with the axis of the clutch.

55.51	Radially overlapping convolutions:
	This subclass is indented under subclass 55.5. Subject matter wherein the coils of the elongated element overlie each other substantially in a plane transverse to the rotational axis of the clutch.

55.6	Plural resilient members:
	This subclass is indented under subclass 55.3. Subject matter including plural resiliently yieldable members.

55.61	Coil springs with center line spaced from rotational axis:
	This subclass is indented under subclass 55.6. Subject matter wherein each of the resiliently yieldable members is comprised of an elongated elastic element coiled about a center line other than the rotational axis of the clutch.

55.62	Center line of coil springs parallel to rotational axis:
	This subclass is indented under subclass 55.61. Subject matter wherein each of the elongated resilient or elastic members is coiled about a center line that is substantially parallel to the rotational axis of the clutch.

55.7	Coil spring with center line spaced from rotational axis:
	This subclass is indented under subclass 55.3. Subject matter wherein there is a single resiliently yieldable member comprised of an elongated resilient or elastic element coiled about a center line other than the rotational axis of the clutch.

[List of Patents for class 192 subclass 56.1]

56.1

Overload release:

This subclass is indented under subclass 54.1. Subject matter wherein engaged clutch elements, coupling input and output shafts of a selectively engageable clutch, release or slip when subjected to an excessive torsional strain on one of the shafts.

(1) Note. See the line note in subclass 54.1 for the line between Class 192 and Class 464.

SEE OR SEARCH THIS CLASS, SUBCLASS:

55.1,

for structure in the drive-line of the clutch which slips on overload while the clutch remains engaged (e.g., the combination of a clutch and overload coupling).

SEE OR SEARCH CLASS:

464,	Rotary Shafts, Gudgeons, Housings, and Flexible Couplings for Rotary Shafts, subclasses 32+ for structure wherein torque transmission is disrupted by breakage of a frangible element that may be replaced.

56.2	Coil:
	This subclass is indented under subclass 56.1. Subject matter wherein one of the clutch elements is a helically coiled resilient device which frictionally engages the other clutch element to transmit torque.

[List of Patents for class 192 subclass 56.3]

56.3

Fluid operated clutch:

This subclass is indented under subclass 56.1. Subject matter wherein the clutch elements are moved to or held in either an engaged or released condition by means of a liquid or gas under pressure.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.601+,

and 85.01+, for fluid activated clutches, per se.

56.31	Axially engaged:
	This subclass is indented under subclass 56.3. Subject matter wherein movement of the clutch elements to the engaged condition is in a direction parallel to the rotation axis of the clutch.

56.32	Positive:
	This subclass is indented under subclass 56.31. Subject matter wherein the clutch elements have formations thereon which intermesh to transmit torque without slip.

56.33	Ball or roller:
	This subclass is indented under subclass 56.32. Subject matter wherein at least one of the formations is a spherical or generally cylindrical member.

[List of Patents for class 192 subclass 56.4]

56.4

Magnetic or electromagnetic:

This subclass is indented under subclass 56.1. Subject matter wherein the clutch elements are moved to or held in either an engaged or released condition by means of at least one permanent magnet or electromagnetic coil.

SEE OR SEARCH THIS CLASS, SUBCLASS:

84+,	for magnetically or electromagnetically operated clutches, per se.

56.41	Axially engaged:
	This subclass is indented under subclass 56.4. Subject matter wherein movement of the clutch elements to the engaged condition is in a direction parallel to the rotation axis of the clutch.

56.42	Positive:
	This subclass is indented under subclass 56.41. Subject matter wherein the clutch elements have formations thereon which intermesh to transmit torque without slip.

56.43	Ball or roller:
	This subclass is indented under subclass 56.42. Subject matter wherein at least one of the formations is a spherical or generally cylindrical member.

56.5	Clutch elements remain disengaged after overload corrected:
	This subclass is indented under subclass 56.1. Subject matter wherein the clutch elements release from engagement when subjected to excessive torsional strain and remain released after the excessive torsional strain is reduced.

56.51

Having separate latch to hold clutch elements disengaged:

This subclass is indented under subclass 56.5. Subject matter having a spring biased detent or pivoted pawl which positively engages another member to prevent the clutch elements from reengaging until reset by an operator.

SEE OR SEARCH THIS CLASS, SUBCLASS:

114,	for locking devices, per se.
150,	for overload release mechanism, per se.

56.52	Axially engaged:
	This subclass is indented under subclass 56.51. Subject matter wherein movement of the clutch elements to the engaged condition is in a direction parallel to the rotation axis of the clutch.

56.53	Positive:
	This subclass is indented under subclass 56.52. Subject matter wherein the clutch elements have formations thereon which intermesh to transmit torque without slip.

56.54	Ball or roller:
	This subclass is indented under subclass 56.53. Subject matter wherein at least one of the formations is a spherical or generally cylindrical member.

56.55	Axially engaged:
	This subclass is indented under subclass 56.5. Subject matter wherein movement of the clutch elements to the engaged condition is in a direction parallel to the rotation axis of the clutch.

56.56	Positive:
	This subclass is indented under subclass 56.55. Subject matter wherein the clutch elements have formations thereon which intermesh to transmit torque without slip.

56.57	Ball or roller:
	This subclass is indented under subclass 56.56. Subject matter wherein at least one of the formations is a spherical or generally cylindrical member.

56.6	Axially engaged:
	This subclass is indented under subclass 56.1. Subject matter wherein movement of the clutch elements to the engaged condition is in a direction parallel to the rotation axis of the clutch.

56.61	Positive:
	This subclass is indented under subclass 56.6. Subject matter wherein the clutch elements have formations thereon which intermesh to transmit torque without slip.

56.62	Ball or roller:
	This subclass is indented under subclass 56.61. Subject matter wherein at least one of the formations is a spherical or generally cylindrical member.

[List of Patents for class 192 subclass 57]

Fluent material and mechanical:

This subclass is indented under subclass 30. Clutches include an ordinary friction or other mechanically clutching part combined with a clutch in which the resisting part is enveloped in the clutching material.

SEE OR SEARCH THIS CLASS, SUBCLASS:

3.21+,	for a combination of vortex-flow drive and clutch.
48.1+,	for other plural clutch-assemblages.

SEE OR SEARCH CLASS:

188,	Brakes, subclass 271 for a surface- friction brake combined with a fluid- resistance brake.

[List of Patents for class 192 subclass 58.1]

58.1

Fluent material:

This subclass is indented under subclass 30. Subject matter in which a clutching medium envelopes at least one of a pair of clutch members and is a fluid or any substance the particles of which readily flow over each other.

SEE OR SEARCH CLASS:

60,	Power Plants, subclasses 330+ for fluid couplings which include the transmission of torque through kinetic forces resulting from acceleration and deceleration of the fluid effective between the driving and driven elements of the coupling. Where the driven element includes a fluid channel or space between vanes which communicates with regions of the driving element which are maintained at different fluid pressures or are moving at different velocities, the resulting forces are considered kinetic and such structures are found in Class 60.
188,	Brakes, subclasses 266+ for a similar structure used as a brake.
464,	Rotary Shafts, Gudgeons, Housings and Flexible Couplings for Rotary Shafts, subclasses 24+ for a flexible coupling wherein a liquid or gas is used to affect the coupling, and see the line note with Class 192 under the class definition of Class 464.

[List of Patents for class 192 subclass 58.2]

58.2

Fluid:

This subclass is indented under subclass 58.1. Subject matter wherein the clutching medium is a liquid or a gas.

(1) Note. Where the clutching medium is not a liquid or gas (e.g., a powder or gellike plastic fluid mass) classification is proper in subclass 58.1.

58.3	Vane clutch:
	This subclass is indented under subclass 58.2. Subject matter wherein at least one of the members is provided with a projection acting as a scoop or paddle which propels the clutching medium against the other of the members to transmit torque therebetween.

58.4	Viscous shear:
	This subclass is indented under subclass 58.2. Subject matter wherein torque is transmitted by fluid friction acting on surfaces of the clutch members.

58.41	Multiple plate:
	This subclass is indented under subclass 58.4. Subject matter wherein there is a plurality of disclike elements on one clutch member interleaved with a plurality of disclike elements on the other of the clutch members.

58.42	Variable gap or volume:
	This subclass is indented under subclass 58.41. Subject matter wherein means are provided for adjusting the spacing between the disclike elements or for adjusting the volume of a chamber in which the liquid or gas is contained.

58.43	Variable gap or volume:
	This subclass is indented under subclass 58.4. Subject matter wherein means are provided for adjusting the spacing of the surfaces of the clutch members or adjusting the volume of a chamber in which the liquid or gas is contained.

[List of Patents for class 192 subclass 58.5]

58.5

Separate reservoir:

This subclass is indented under subclass 58.4. Subject matter wherein one of the clutch members rotates in a space defined by a housing, which housing has a working chamber in which fluid friction between the members occurs and wherein a separate storage chamber is provided in which the liquid or gas can be collected.

(1) Note. The housing referred to above may be defined by the other of the members; e.g., a housing is coupled to a part to be driven and a disc rotatable in the housing is coupled to a driving part.

58.6	Automatic regulation:
	This subclass is indented under subclass 58.5. Subject matter wherein means are provided to control the flow of fluid between the working chamber and the storage chamber in response to at least one sensed condition.

58.61	Magnetic or electric:
	This subclass is indented under subclass 58.6. Subject matter wherein the means which controls the flow between chambers is magnetically or electrically operated.

58.62	Temperature and speed:
	This subclass is indented under subclass 58.6. Subject matter wherein the sensed condition includes both a level of heat and a rate of rotation.

58.63	Temperature:
	This subclass is indented under subclass 58.6. Subject matter wherein the sensed condition is a level of heat.

58.64

Coolant and clutching medium:

This subclass is indented under subclass 58.63. Subject matter wherein the sensed condition is a level of heat in the clutching medium and the level of heat in a separate liquid used to cool a related device.

(1) Note. The related device is typically an internal combustion engine.

SEE OR SEARCH CLASS:

123,	Internal-Combustion Engines, subclass 41.12 , for similar devices in combination with an internal combustion engine.

58.65	Ambient and clutching medium:
	This subclass is indented under subclass 58.63. Subject matter wherein the sensed condition is a level of heat in the clutching medium and the level of heat of air external to and immediately surrounding the clutch.

58.66	Ambient and coolant:
	This subclass is indented under subclass 58.63. Subject matter wherein the sensed condition is a level of heat in air external to and immediately surrounding the clutch and the level of heat in a separate liquid used to cool a related device.

58.67	Clutching medium:
	This subclass is indented under subclass 58.63. Subject matter wherein the sensed condition is the level of heat in the clutching medium.

58.68	Ambient:
	This subclass is indented under subclass 58.63. Subject matter wherein the sensed condition is the level of heat in air external to and immediately surrounding the clutch.

58.681	Bimetallic:
	This subclass is indented under subclass 58.68. Subject matter wherein the level of heat of the surrounding air is sensed by an element comprised of at least two metals having dissimilar coefficients of thermal expansion, the element moving in response to a change in the level of heat to effect control of the level of clutching medium in the working chamber (e.g., by operating a valve).

58.682	Spiral:
	This subclass is indented under subclass 58.681. Subject matter wherein the element is coiled in plural convolutions which lie substantially in the same plane.

58.683	Resilient or adjustable mounting feature:
	This subclass is indented under subclass 58.682. Subject matter wherein at least one end of the element is attached to a support on the clutch by recoilably yieldable means or by means permitting a change in the position of attachment.

58.684	Mounting feature:
	This subclass is indented under subclass 58.681. Subject matter wherein the specifics of the attachment of the element to the clutch are cited as significant.

58.7	Pump-out feature:
	This subclass is indented under subclass 58.5. Subject matter wherein a device is provided to force fluid from the working chamber to the storage chamber and wherein the shape, arrangement or material of said device is cited as significant.

58.8	Specific valve:
	This subclass is indented under subclass 58.5. Subject matter wherein a device is provided for opening and closing a fluid passage extending between the storage and working chamber and wherein the shape, arrangement or material of said device is cited as significant.

58.9	Radial vane:
	This subclass is indented under subclass 58.2. Subject matter, having a clutch member disposed radially inward of another clutch member, and one of the clutch members carries bladelike elements which slidably engage the other member, rotation being transmitted through circumferential compression of the fluid.

58.91	Vanes on inner member:
	This subclass is indented under subclass 58.9. Subject matter wherein the bladelike elements are carried by the radially inward member to slidably engage an inwardly facing surface on the other member.

58.92	Spring-biased:
	This subclass is indented under subclass 58.91. Subject matter wherein recoilably yieldable means are provided to impart a radially outwardly directed force on the bladelike elements.

[List of Patents for class 192 subclass 59]

Axially movable piston:

This subclass is indented under subclass 58.1. Clutches + in which the rotating driving member propels one or more pistons against the action of the clutching fluid in a direction parallel to the axis of rotation.

SEE OR SEARCH CLASS:

188,	Brakes, subclasses 290+ for similar structure used as a brake.

[List of Patents for class 192 subclass 60]

Transversely movable piston:

This subclass is indented under subclass 58.1. Clutches + in which the pistons move transversely to the axis of rotation, against the action of the clutching fluid.

SEE OR SEARCH CLASS:

188,	Brakes, subclasses 290+ for similar structure used as a brake.

[List of Patents for class 192 subclass 61]

Gear-pump type:

This subclass is indented under subclass 58.1. Clutches + in which the rotation is transmitted by means of the clutching fluid, which is forced between meshed gears.

(1) Note. Both this subclass, and Class 475, Planetary Gear Transmission Systems or Components, subclasses 91+, contain planetary units including gear pumps so arranged that when fluid flow through the pump is unrestricted, the unit slips, as the fluid flow is restricted, the unit planetates, and when fluid flow is completely shut off, the gear elements forming the pump are locked against relative rotation and the unit is locked. Where a planet pinion of the unit drives a separate gear pump, the pump, in fact, operates as a planet pinion brake, and such art will be found in the appropriate one of the above listed subclasses in Class 475. Where a planet pinion and its intermeshing sun or orbit gear together constitute the gear pump, the device will be found in this subclass (192/61).

SEE OR SEARCH CLASS:

188,	Brakes, subclass 292 for similar structure used as a brake.
418,	Rotary Expansible Chamber Devices, subclasses 54+ for rotary expansible chamber devices for working members having planetary or planetating movement; subclasses 166+ for rotary expansible chamber devices of the moving cylinder type having intermeshing peripheral surfaces and subclasses 191+ for rotary expansible devices having interengaging rotary members.
475,	Planetary Gear Transmission Systems or Components, subclasses 91+ , and see (1) Note above.

[List of Patents for class 192 subclass 62]

Plow-lifting type:

This subclass is indented under subclass 30. Clutches adapted for use in raising plows.

SEE OR SEARCH CLASS:

172,	Earth Working, subclasses 403+ and 407+ especially subclasses 410+ for earth working apparatus comprising a clutch associated with a wheel for lifting a plow.

[List of Patents for class 192 subclass 63]

Free-engine type:

This subclass is indented under subclass 30. Clutches for engine-drives designed to permit at times the engine to run free without transmitting power.

SEE OR SEARCH THIS CLASS, SUBCLASS:

42,	for automatic type of free-engine clutch.

[List of Patents for class 192 subclass 64]

Velocipede free wheel:

This subclass is indented under subclass 30. Clutches designed to permit a velocipede wheel to run freely when the pedals are held.

SEE OR SEARCH THIS CLASS, SUBCLASS:

41+,	for one-way clutches.

65	Axially and transversely engaging:
	This subclass is indented under subclass 30. Clutches in which the engaging elements of the clutches have both a motion parallel and a motion transverse to the axis of rotation.

66.1	Axially engaging:
	This subclass is indented under subclass 30. Subject matter wherein at least one engaging member is movable parallel to the axis of rotation to engage or disengage at least one other member.

66.2	Conical or frustoconical:
	This subclass is indented under subclass 66.1. Subject matter wherein engaging faces of the members are in the form of a cone or frustocone.

66.21	Plural radially spaced surfaces:
	This subclass is indented under subclass 66.2. Subject matter, with two or more concentric conical or frustoconical surfaces on each engaging member.

66.22	Spring engaged:
	This subclass is indented under subclass 66.2. Subject matter wherein the faces are moved to a torque transmitting position by the action of a recoilably yieldable member.

66.23	Spring released:
	This subclass is indented under subclass 66.2. Subject matter wherein the faces are moved to the disengaged position by the action of a recoilably yieldable member.

66.3	Planar radially extending:
	This subclass is indented under subclass 66.1. Subject matter wherein engaging faces of the members are disposed in a plane perpendicular to the rotation axis.

66.31	Spring engaged:
	This subclass is indented under subclass 66.3. Subject matter wherein the faces are moved to a torque transmitting position by the action of a recoilably yieldable member.

66.32	Spring released:
	This subclass is indented under subclass 66.3. Subject matter wherein the faces are moved to the disengaged position by the action of a recoilably yieldable member.

[List of Patents for class 192 subclass 69]

Positive:

This subclass is indented under subclass 66.1. Clutches in which the axially movable members carry elements that intermesh to transmit torque without slip.

SEE OR SEARCH THIS CLASS, SUBCLASS:

108,	for improvements in the engaging faces, per se, of interlocking or positively engaged clutches.

69.1	Pivoting positive clutch element:
	This subclass is indented under subclass 69. Subject matter wherein at least one of the members includes an element which is swingably mounted to a point of attachment thereto and is engageable with another of the clutch members.

69.2	Plunger disconnect:
	This subclass is indented under subclass 69. Subject matter wherein a finger moving generally transversely to the axis of rotation of the clutch engages cooperating structure (e.g., a screw) which causes the engaging members to move to the disengaged position.

69.3	Pilot pawl:
	This subclass is indented under subclass 69. Subject matter wherein a member is provided with a swinging finger which engages ratchet teeth and is effective to cause synchronous engagement of the intermeshed elements.

[List of Patents for class 192 subclass 69.4]

69.4

Wheel hub clutched to axle:

This subclass is indented under subclass 69. Subject matter wherein the positive clutch engages a wheel hub to an axle (e.g., in a four-wheel drive vehicle).

SEE OR SEARCH THIS CLASS, SUBCLASS:

54.2,

for hub clutches which engage in response to torque on the axle.

SEE OR SEARCH CLASS:

180,	Motor Vehicles, subclass 247 for a manual means to disengage drive to one or more, but fewer than all four of the wheels.
403,	Joints and Connections, subclass 1 for selectively engageable hub to shaft connections.

69.41	Fluid pressure:
	This subclass is indented under subclass 69.4. Subject matter wherein one of the members of the positive clutch is shifted either into or out of engagement with another member by hydraulic or pneumatic pressure.

69.42	Electromagnetic:
	This subclass is indented under subclass 69.4. Subject matter wherein one of the members of the positive clutch is shifted axially either into or out of engagement with another member by the action of a solenoid or electric motor.

69.43	Manual:
	This subclass is indented under subclass 69.4. Subject matter wherein one of the members of the positive clutch is shifted axially into or out of engagement with another member by an operator manipulated knob or handle disposed on the hub or axle.

69.5	Ball or roller:
	This subclass is indented under subclass 69. Subject matter wherein at least one of the intermeshed elements is generally spherical or cylindrical and rotatably mounted relative to its corresponding member.

69.6	Cylindrical pin:
	This subclass is indented under subclass 69. Subject matter wherein at least one of the intermeshed elements is an elongated element of generally circular cross-section that is fixedly mounted to its corresponding member.

69.61	Axial pin on only one member:
	This subclass is indented under subclass 69.6. Subject matter wherein only one member carries an elongated element which extends generally parallel to the rotation axis.

69.62

Pin engages aperture in other member:

This subclass is indented under subclass 69.61. Subject matter wherein the other of the engaging elements includes apertures to receive the elongated element.

(1) Note. Here aperture is defined as a hole, slot, or recess defined by a periphery that surrounds the pin.

69.63	Radial pin:
	This subclass is indented under subclass 69.6. Subject matter wherein the elongated element extends generally transverse to the clutch rotation axis.

69.7	Axial-radial:
	This subclass is indented under subclass 69. Subject matter wherein one of the members includes elements extending axially from the member and joined thereto only on a radially extending surface of the member, and the other engaging member has radially extending elements adapted to interlock with the axially extending elements, the radially extending elements being joined to its associated member at least on one circumferential surface of the member.

69.71

Axially extending projection engages aperture:

This subclass is indented under subclass 69.7. Subject matter wherein the axially extending projection engages an aperture in the other member.

(1) Note. Here aperture is defined as a hole, slot, or recess defined by a periphery that surrounds the axially extending projection.

SEE OR SEARCH THIS CLASS, SUBCLASS:

69.62,

for projections that are cylindrical pins.

[List of Patents for class 192 subclass 69.8]

69.8

Axial-axial:

This subclass is indented under subclass 69. Subject matter wherein a pair of members each include elements extending axially from the members and joined thereto solely on a radially extending surface of the members.

(1) Note.The elements must have a component in the axial direction.

69.81	Sawtooth:
	This subclass is indented under subclass 69.8. Subject matter wherein the axially extending elements on at least one of the coupled members has the form of a tooth having one engaging surface that lies in a plane substantially parallel to or including the rotational axis and an adjacent engaging surface that lies in a plane oblique to the rotational axis.

69.82	Square tooth:
	This subclass is indented under subclass 69.8. Subject matter wherein oppositely facing engaging surfaces on the elements of both members are each perpendicular to an end face of the element.

69.83	With lead-in:
	This subclass is indented under subclass 69.82. Subject matter wherein at least one of the elements includes a configuration to facilitate engagement.

69.9	Radial-radial:
	This subclass is indented under subclass 69. Subject matter wherein the members each include at least one element which extends radially and are joined to their respective member at least on one circumferential surface of the respective member.

69.91	Outward projection on movable member:
	This subclass is indented under subclass 69.9. Subject matter wherein only one of the members moves parallel to the axis of rotation and has at least one element which extends radially from an outer circumferential surface of said one member.

70	Spreading:
	This subclass is indented under subclass 66.1. Clutches in which two axially moving members are spread to engage the companion members of the clutch .

70.11

Interposed, mating clutch-elements:

This subclass is indented under subclass 66.1. Device having an input (i.e., driving) shaft and an output (i.e., driven) shaft rotatable about a common axis and at least three members supported thereby in an array of adjacent members spaced along the axis and co-axial with the shafts, the outer of said members having surfaces facing opposite surfaces of one or more intermediate members; one of said members being constrained to rotate with one of the shafts, another of said members being constrained to rotate with the other of the shafts but being movable along the common axis, and a third of said members being movable along the common axis; the device also having means for moving said members toward one another for mutual engagement of the facing surfaces, whereby the input shaft transmits its rotation to the output shaft when the facing surfaces are mutually engaged.

(1) Note. In this and indented subclasses one clutch-element is connected to one of the shafts and is sandwiched between two other clutch-elements that are connected to the other shaft. In a variation of this arrangement a multiplicity (usually more than three) of clutch-elements is connected for rotation with one shaft and a multiplicity of clutch-elements is connected for rotation with the other shaft, the elements of one shaft alternating with the elements of the other shaft. The variation described is called a "multiple-element clutch-assemblage" in the definitions and notes of the subclasses indented hereunder.

(2) Note. The clutch-assemblage is usually enclosed by a "flywheel" and a "cover plate". A flywheel is a heavy component secured to the input shaft to stabilize rotational momentum thereof, and a cover plate (also known as a "back plate") also encloses a "pressure plate" (which is a component that, compared to a clutch-element, is relatively thick and heavy) and an actuator that urges the pressure plate towards clutch-elements lying between the pressure plate and the flywheel to effect engagement of the clutch-assemblage.

(3) Note. The term "shaft", as used in the definition above, is intended as the generic name of a torque-transmitting member which is referred to by a variety of names, including: shaft, flywheel (usually applied to the input of an automobile), pulley, gear, drum, hub, spindle, axle, sleeve, etc., the named terms being only exemplary of those used.

SEE OR SEARCH THIS CLASS, SUBCLASS:

85.09+,

and 85.24+, for a clutch having more than two mating friction elements.

SEE OR SEARCH CLASS:

188,	Brakes, subclass 71.5 for disclosure of rotationally-fixed elements interleaved between rotatable elements and axially moved to retard rotation of the rotatable elements.

70.12

With means to cool or lubricate clutch parts:

This subclass is indented under subclass 70.11. Device provided with means for reducing the temperature of, or for supplying a friction-reducing fluid to, any of the members or components of a clutch-assemblage.

(1) Note. The term "clutch-assemblage" is defined in (1) Note to the definition of subclass 48.1 above.

SEE OR SEARCH THIS CLASS, SUBCLASS:

113+,

for clutch lubricating and/or cooling means, e.g., per se.

70.13

With removable or replaceable or interchangeable clutch parts:

This subclass is indented under subclass 70.11. Device wherein any of the members or sub-assemblies of the device may be taken out of the clutch-assemblage, or put back into the clutch-assemblage, or wherein one such member or sub-assembly may be exchanged for another such member or sub-assembly.

(1) Note. The term "clutch-assemblage" is defined in (1) Note to the definition of subclass 48.1 above.

(2) Note. It is inherent in any device that is assembled from a plurality of parts that the device may be disassembled and then re-assembled with the same or equivalent parts. Therefore, an original patent placed in this subclass should clearly disclose the features implicit in the title and definition of the subclass.

70.14

Including surface characteristics of clutch-element:

This subclass is indented under subclass 70.11. Device having a distinctive, structurally-significant peculiarity in the engaging face of the member.

(1) Note. Terms such as "segmented", or "faced with leather", or "roughened" or "tapered" are considered to be structurally-significant descriptors of the engaging surface. Functional terms such as "friction surface" are not proper for this subclass (70.14), and clutch-elements so described will be found elsewhere according to their other characteristics.

(2) Note. Compare this subclass (70.14) with subclass 107 of this class (192). A device in this subclass (70.14) relates to a clutch-element clearly identifiable as part of an opposed-element clutch-assemblage, whereas a device of subclass 107 relates to the engaging face of an element, per se, usable in a clutch or brake.

SEE OR SEARCH THIS CLASS, SUBCLASS:

107+,

for engaging elements, and see (2) Note above.

SEE OR SEARCH CLASS:

188,	Brakes, subclass 73.1 for disclosure of surface characteristics enhancing friction of a braking element, and subclass 73.2, for disclosure of a conical braking element.

70.15

Axially tapered mating surfaces:

This subclass is indented under subclass 70.14. Device wherein the engaging face of the member is distinctive by being, at least in part, a frustoconical surface, and wherein the engaging face of a member having mutual engagement with the first-mentioned member is also a frustoconical surface that complements the first-mentioned surface.

(1) Note. A device having clutch-elements whose adjacent complementary engaging surfaces show a profile, on a cross-section passing through the axis of rotation of the clutch-elements, of V-shaped or zigzag configuration, is proper for this subclass (70.15).

70.16

With torque connection between clutch-element and its shaft:

This subclass is indented under subclass 70.11. Device provided with means which (a) transmits rotational force from an input shaft to a member supported thereby, or transmits rotational force from another member to an output shaft that supports the other member, and (b) simultaneously permits movement of either member relative to its supporting shaft.

(1) Note. It is emphasized that this and indented subclasses provide for the connection between a shaft and the clutch-element supported thereby, rather than for the means transmitting rotation from one clutch-element to a mating clutch-element. The permitted movement may be rotational as in subclass 70.17 below, or axially slidable as in subclass 70.19 below, or oscillating about an axis perpendicular to the axis of rotation of the shafts as in this subclass (70.16).

70.17

Resilient torque connection (e.g., for damping vibration):

This subclass is indented under subclass 70.16. Device wherein said means is recoilably yieldable to a limited extent in the rotation direction, whereby the permitted movement is a limited degree of variation between the rotation of a shaft and the rotation of the member supported thereby.

(1) Note. It is emphasized that the amount of variation of transmitted rotation is extremely small, and that the primary purpose of the resilient connection is to absorb shock inherent in the act of causing a stationary clutch-element to be engaged suddenly by a rotating clutch-element. The resilient connection permits the torque to be applied from the shaft to the clutch-element supported thereby (or from the clutch-element to its supporting shaft) without stressing any of the parts to an excessive degree. The "permitted movement" of the clutch-element is rotation momentarily addition to and/or subtractive from the rotation of its supporting shaft. However, the rotation of the clutch-element quickly matches that of its supporting shaft.

SEE OR SEARCH THIS CLASS, SUBCLASS:

200+,

for a subcombination comprising a clutch-element (or similar structure such as a brake element) resiliently mounted on a hub.

70.18

Including chordally disposed connection:

This subclass is indented under subclass 70.17. Device wherein said means comprises a link or strap having two ends, one end of which is attached to a clutch-element (or to an equivalent rotating member such as a pressure plate or flywheel) at a point on the clutch-element radially spaced from the axis of rotation thereof, and the other end of which link is attached to a driving or driven shaft (or to an equivalent rotating member integral therewith) at a point on the shaft radially spaced from the axis of rotation thereof and angularly spaced from the first-mentioned attachment.

(1) Note. The attachment at either end of the link may take the form of a pivot pin passing through a hole in the link or a resilient connection between the link and the clutch-element or its supporting shaft. The necessary requirement for this subclass (70.18) is not the form of attachment, but rather that the link extend between the two rotating parts (i.e., the clutch-element and its supporting shaft) as if the link were a chordal link intersecting circles of revolution traced by link-connecting parts of the clutch-element and its shaft.

SEE OR SEARCH THIS CLASS, SUBCLASS:

212+,

for a subcombination of a clutch-element connected to a hub by a helical-coil spring wherein the spring is chordally disposed between the clutch-element and the hub.

70.19	Axially slidable connection:
	This subclass is indented under subclass 70.16. Device wherein the means comprises portions integral with or secured to either shaft extending along or parallel to the axis of rotation thereof which portions connect the member to its supporting shaft for rotation and permit movement only in a direction parallel to said axis.

70.2	Spline connection for multiple clutch-elements:
	This subclass is indented under subclass 70.19. Device wherein the portions comprise gear-like teeth and grooves in the shaft (or drum) mating with complementary grooves and teeth in the member, (or comprise ribs and slots in the shaft (or drum) mating with complementary slots and protrusions in the member), and wherein a plurality of first members are in torque-transmitting connection with an input shaft, a plurality of second members are in torque-transmitting connection with an output shaft coaxial with the input shaft, and the first and second members alternate with one another along the axis of the shafts.

70.21

With means to move multiple clutch-elements axially and sequentially:

This subclass is indented under subclass 70.11. Device including a multiple-element clutch-assemblage the members of which are arranged along an axis of rotation, and provided with means for moving the members along said axis, wherein said means causes said members to engage one another in a predetermined succession of mutual engagements along said axis, or to disengage from one another in the same or an opposite succession of mutual disengagements.

(1) Note. The purpose of the structure described is to ensure that torque from one shaft is applied gradually to the other shaft rather than suddenly.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48.7,

and 52.1+, for other arrangements for progressively transmitting load from an input to an output shaft.

70.22

With means to move clutch-element axially and latch into engaged or disengaged position:

This subclass is indented under subclass 70.11. Device provided with means for moving a member along said axis and with means additional to the member-moving means, which additional means maintains the members in close contact with one another, or maintains the members apart from one another, until the members are released to permit movement thereof by member-moving means.

(1) Note. Some devices of subclasses 70.29 and 70.3 below include a toggle linkage to move a pressure plate or the clutch-elements axially. A toggle linkage comprises two pivotable links joined together by an intermediate pivot, and such linkage is inherently capable of latching itself if the intermediate pivot is moved "overcenter", i.e., past an imaginary line connecting the end pivots. Such structure will be proper for this subclass (70.22) only when the toggle linkage locks itself, i.e., is moved "overcenter".

SEE OR SEARCH THIS CLASS, SUBCLASS:

70.29,	and 70.3, for a toggle-link actuator and see (1) Note above.
114+,	for element-locking means, e.g., per se.

70.23

With cam or wedge contacting clutch-element or pressure plate for axial movement thereof:

This subclass is indented under subclass 70.11. Device provided with means for moving a member along said axis wherein the member-moving means includes a movable component having a surface in sliding engagement with a surface portion of a member or of a pressure plate, the component surface and the member or plate surface being so related and contoured that movement of the component in a predetermined direction is converted into axial movement of the member or pressure plate.

(1) Note. A device is proper for this subclass (70.23) even if sliding friction between the cam surfaces is reduced by use of a roller at the area of contact between the cam and the clutch-element or pressure plate.

(2) Note. The movement of the component is usually oscillation in the case of a cam, and reciprocation (often in a radial direction) in the case of a wedge.

(3) Note. A device is proper for this subclass (70.23) if its cam or wedge contacts a cam surface on a flywheel that has an engaging surface equivalent to a clutch-element surface.

70.24	By cam surface on bell-crank:
	This subclass is indented under subclass 70.23. Device wherein the component comprises a lever pivoted between its ends for oscillation in a plane parallel to the axis of rotation of the clutch-assemblage, and the lever having the sliding surface at one of its ends, whereby oscillation of the component within the plane is converted into axial movement of the member of the pressure plate.

70.251

With adjustable means to move clutch-element axially (e.g., to compensate for wear):

This subclass is indented under subclass 70.11. Device provided with member-moving means for moving a first one of the members along said axis and with means ("additional means") additional to the member-moving means, which additional means is capable of axially changing the positional relationship between the first member and another of the members mating therewith, such change being additional to the movement effected by the member-moving means.

(1) Note. The structure described is for the purpose of offsetting the decrease in the axial dimension of the clutch-elements due to attrition of the surfaces of the elements that occurs as they are repeatedly engaged and disengaged under load.

SEE OR SEARCH THIS CLASS, SUBCLASS:

85.62,	for a fluid-operated clutch including a wear compensator that operates by fluid actuator adjustment or control rather than by adjustment of relative positions of friction elements.
111.1+,	for wear-compensators, per se.

70.252	Automatic:
	This subclass is indented under subclass 70.251. Device in which the additional means operates to change the positional relationship between the members without human assistance or intervention beyond that which occurs during normal use of the device.

70.26

Including plural adjusting screws (e.g., to equalize pressure angularly):

This subclass is indented under subclass 70.251. Device provided with two or more of said additional means, each of which additional means comprises a bolt or threaded male member rotatable relative to a nut or threaded female member.

(1) Note. Each of the plurality of screws or bolts is disposed radially outwardly of the axis of rotation of the shafts, and each is angularly spaced from the others (usually equally spaced) so that the amount of adjustment of each of the screws may be chosen to compensate for that degree of wear required by the portion of the clutch-element surface adjacent to that screw.

70.27

With spring means to move clutch-element axially:

This subclass is indented under subclass 70.11. Device provided with means for moving a member along said axis, wherein the member-moving means includes at least one elastic body that tends to recover its shape when distorted.

(1) Note. A "Belleville" spring (i.e., a relatively thin, resilient disc that is dished or tapered in shape) is found herein, as well as a common coil spring. Usually the spring acts along a line parallel to or coinciding with the axis of rotation of the shaft.

70.28

To separate engaged clutch-elements:

This subclass is indented under subclass 70.27. Device wherein the elastic bodies tend to move the members apart from one another.

(1) Note. Examples of devices in this subclass (70.28) include: a device wherein a spring is used alternatively to engage or to disengage the clutch-elements, and a device wherein a spring is stressed (as by actuating a lever) only when the clutch-elements are to be disengaged. The necessary requirement is not the means for urging the clutch-elements into engagement (such means will be found elsewhere in this class (192) but rather than a spring is used to disengage the clutch-elements.

70.29

And actuator lever pivoted on pressure plate:

This subclass is indented under subclass 70.27. Device wherein the member-moving means also includes a bar oscillatable about a fulcrum by application of force thereto, which fulcrum is connected to or mounted on a pressure plate, said fulcrum being a pivot pin or the equivalent of a "knife edge" about which the bar oscillates.

SEE OR SEARCH THIS CLASS, SUBCLASS:

70.22,	for a "toggle linkage" pivoted on a pressure plate, and see (1) Note to the definition of subclass 70.22 for a relationship between the subclasses.
70.3,	for an actuator level pivoted on a back plate, or on both a back plate and a pressure plate.

[List of Patents for class 192 subclass 70.3]

70.3

With actuator lever pivoted on pressure plate or back plate to move clutch-element axially:

This subclass is indented under subclass 70.11. Device provided with means for moving a member along said axis, wherein the member-moving means includes a bar oscillatable about a fulcrum by application of force thereto, which fulcrum is connected to or mounted on a pressure plate or a cover plate, said fulcrum being a pivot pin or the equivalent of a "knife edge" about which the bar oscillates.

SEE OR SEARCH THIS CLASS, SUBCLASS:

70.22,	for a "toggle linkage" pivoted on a pressure plate and a cover plate, and see (1) Note to the definition of subclass 70.22 for a relationship between the subclasses.
70.29,	for an actuator lever pivoted on a pressure plate and opposed or aided by a spring means.

	Transversely engaged:
	This subclass is indented under subclass 30. Clutches in which the movable engaging element has movement transverse to the axis of rotation.

71	Positive:
	This subclass is indented under the unnumbered subclass, Transversely engaged. Clutches under Transversely engaged in which the clutch elements engage positively.

72	Interior and exterior:
	This subclass is indented under the unnumbered subclass, Transversely engaged. Clutches under Transversely engaged in which the transversely-moving member or members engage other members both exteriorly and interiorly.

73	Opposing:
	This subclass is indented under subclass 72. Clutches in which the member or members moving transversely grip an intermediate member.

74	Interior:
	This subclass is indented under the unnumbered subclass, Transversely engaged. Clutches under Transversely engaged in which the member moving transversely, becomes engaged with the interior of a rotatable member.

75	Expanding:
	This subclass is indented under subclass 74. Clutches in which two or more members, moving transversely away from the axis of rotation, engage the interior of the rim or rotatable member.

76	Radial:
	This subclass is indented under subclass 75. Clutches in which the motion of the transversely-engaging members is radial.

[List of Patents for class 192 subclass 77]

Split ring:

This subclass is indented under subclass 75. Clutches in which the transversely-moving member is a split ring.

(1) Note. The split ring is usually released from engagement by its own resilience.

78	Cam operated:
	This subclass is indented under subclass 77. Clutches in which the split ring is spread by means of a cam.

79	Exterior:
	This subclass is indented under the unnumbered subclass, Transversely engaged. Clutches under Transversely engaged, in which the transversely moving members engage the exterior of the rotating part.

80	Strap:
	This subclass is indented under subclass 79. Clutches in which the exterior transversely-moving member is a flexible strap or band.

81	Multiple folds:
	This subclass is indented under subclass 80. Clutches in which the strap encircles the drum or wheel in two or more folds.

82	Operators:
	This subclass is indented under subclass 30. Subject matter including an actuating device that causes the power-transmitting device to transition into or out of a state in which it provides the driving continuity between the driving and driven parts.

83	Multiple for same clutch:
	This subclass is indented under subclass 82. Devices which include two or more devices for operating the same clutch.

[List of Patents for class 192 subclass 84.1]

84.1

Electric or magnetic:

This subclass is indented under subclass 82. Subject matter, wherein frictional or interlocking engagement of driving and driven clutch parts is effected by attraction between elements having opposite potential or polarity.

SEE OR SEARCH THIS CLASS, SUBCLASS:

3.56,	12, 17, or 18 for an electric or magnetic component involving a clutch and brake system.
21.5,	for a field responsive system.
40,	for an electric or magnetic component in a manually controlled clutch.
48.2,	for an electrically actuated plural clutch assemblage.
53.2,	for a positive frictional clutch operated by electric or magnetic means.
54.4,	for a magnetic or electromagnetic torque responsive clutch.
56.4,	+ for an overload release having magnetic or electromagnetic means
69.42,	for a wheel hub clutched to axle having electromagnetic means.
90,	for an operator that is spring engaged having electric release.

SEE OR SEARCH CLASS:

188,	Brakes, subclasses 158+ for an electric operator for a frictional damping system.
310,	Electrical Generator or Motor Structure, subclasses 92+ for an electrically operated clutch in a motor or generator.
335,	Electricity: Magnetically Operated Switches, Magnets, and Electromagnets, subclasses 220+ for electromagnetic operators, per se.
464,	Rotary Shafts, Gudgeons, Housings, and Flexible Couplings for Rotary Shafts, subclass 29 for an electrical or magnetic coupling.

84.2	Plural coils:
	This subclass is indented under subclass 84.1. Subject matter, wherein clutch engagement is effected by the attraction between poles of opposite magnetic polarity and these poles are the result of a magnetic field produced by the flow of electric current in two or more distinct windings of conductors.

84.21	Plural armatures:
	This subclass is indented under subclass 84.2. Subject matter, wherein two or more windings effect movement of two or more independently movable, magnetizable members.

84.3	Including permanent magnet:
	This subclass is indented under subclass 84.1. Subject matter, wherein a material which naturally attracts iron provides opposite polarities that affect engagement of the driving and driven clutch parts.

84.31	And electromagnet:
	This subclass is indented under subclass 84.3. Subject matter, wherein a field produced by the flow of electric current in a coiled conductor also affects engagement of the clutch parts.

84.4	Electrostatic:
	This subclass is indented under subclass 84.1. Subject matter, wherein engagement of driving and driven clutch parts is effected by the electro-adhesive forces between a conductive member and a semi-conductive member subjected to an electric-potential difference.

[List of Patents for class 192 subclass 84.5]

84.5

Air gap adjustment:

This subclass is indented under subclass 84.1. Subject matter, wherein structure is provided to set to a predetermined value a distance between elements of opposite magnetic polarities when the clutch parts are in a disengaged condition.

SEE OR SEARCH THIS CLASS, SUBCLASS:

110,	for adjusting devices, per se.
111.1+,	for wear compensators, per se.

84.51

Automatic:

This subclass is indented under subclass 84.5. Subject matter, wherein the distance is set without manipulation by an operator.

SEE OR SEARCH THIS CLASS, SUBCLASS:

111.1+,

for automatic wear compensators, per se.

84.6	Rotary electric motor is clutch actuator:
	This subclass is indented under subclass 84.1. Subject matter, wherein the attraction between elements of opposite magnetic polarity produces a relative rotation between the elements which, through a motion converting mechanism, effects engagement of driving and driven clutch parts.

84.7	Mechanical force increasing means:
	This subclass is indented under subclass 84.1. Subject matter, wherein structure is provided to amplify a clutch-engaging force after an initial clutch engagement is effected by the attraction between elements of opposite magnetic polarity.

[List of Patents for class 192 subclass 84.8]

84.8

Operator for transversely engaging elements:

This subclass is indented under subclass 84.1. Subject matter, wherein driving and driven parts rotate about an axis and are engageable by a motion in a direction perpendicular to said axis.

SEE OR SEARCH THIS CLASS, SUBCLASS:

71,	and 81, for transversely engaging clutches, per se.

84.81

Coil spring:

This subclass is indented under subclass 84.8. Subject matter, wherein one of the driving and driven clutch parts is an elongated member wound into a helix shape that is adapted to unwind into or out of frictional engagement with the other clutch part.

SEE OR SEARCH THIS CLASS, SUBCLASS:

89.2+,

for a spring-engaged operator.

84.9	Operator for axially engaging elements:
	This subclass is indented under subclass 84.1. Subject matter, wherein the driving and driven clutch parts rotate about an axis and are engageable by a motion in a direction parallel to said axis.

84.91

Interposed friction elements:

This subclass is indented under subclass 84.9. Subject matter, wherein frictional engagement is provided by three or more friction elements with one or more of the friction elements being sandwiched between adjacent elements.

SEE OR SEARCH THIS CLASS, SUBCLASS:

70.11+,

appropriate subclasses for clutches, per se, having interposed friction elements.

84.92

Positively engaging elements:

This subclass is indented under subclass 84.9. Subject matter, wherein the driving and driven clutch parts carry formations which interlock to transmit torque without slip.

SEE OR SEARCH THIS CLASS, SUBCLASS:

69.42,

for positively engaging clutches, per se.

84.93	Magnetic flux path spaced from engaging elements:
	This subclass is indented under subclass 84.9. Subject matter, wherein the engagement is effected by a magnetic circuit which bypasses the engaging surfaces of the clutch parts.

84.94	Specified torque transmitting spring:
	This subclass is indented under subclass 84.9. Subject matter, wherein one or more of the elements moving parallel to the axis is connected to one of the driving and driven clutch parts by one or more resilient members and wherein the shape, arrangement, or material of the one or more resilient members is cited as significant.

84.941	Nonmetallic:
	This subclass is indented under subclass 84.94. Subject matter, wherein the one or more resilient members is formed of a material other than metal.

84.95	With slip rings:
	This subclass is indented under subclass 84.9. Subject matter, wherein an electromagnet is carried by and rotates with one of the driving and driven parts and electric current is supplied to the electromagnet by a connection including brushes and rotary contacts.

84.951	With pulley or gear:
	This subclass is indented under subclass 84.95. Subject matter, wherein torque is transmitted to or from one of the driving and driven clutch parts by means of a toothed member or a torque transmitting belt or chain.

84.96	Fixed concentric coil:
	This subclass is indented under subclass 84.9. Subject matter, wherein a stationary, annular electromagnetic coil surrounds the clutch axis and magnetizes one of the driving and driven clutch parts to provide a pole piece which attracts the other of the driving and driven clutch parts into engagement therewith.

84.961	With pulley or gear:
	This subclass is indented under subclass 84.96. Subject matter, wherein torque is transmitted to or from one of the driving and driven clutch parts by means of a toothed member or a torque transmitting belt or chain.

85.01

Fluid pressure:

This subclass is indented under subclass 82. Subject matter in which the actuating device is powered by the action of a fluid under pressure.

SEE OR SEARCH THIS CLASS, SUBCLASS:

3.29+,	and 3.33, for a fluid-pressure operator to engage or actuate a clutch that is combined with a vortex-flow drive.
48.601,	for plural clutches at least one of which is fluid-pressure operated.
56.3,	for an overload release mechanism in a fluid-pressure operated clutch.

SEE OR SEARCH CLASS:

92,	Expansible Chamber Devices, appropriate subclassesfor an expansible chamber device, per se, even though disclosed as a means to operate a clutch.
303,	Fluid-Pressure and Analogous Brake Systems, appropriate subclassesfor systems of distribution of fluid to motors of more general application.

85.02	Operator force derived from clutch input or output:
	This subclass is indented under subclass 85.01. Subject matter in which power is transmitted from one of the driving and driven parts via the fluid to the actuating device.

85.03

Elastic (e.g., diaphragm, pneumatic tube):

This subclass is indented under subclass 85.01. Subject matter in which the actuating device includes a flexible element that flexes in response to changes in fluid pressure.

(1) Note. Devices in which the actuating device includes sliding seals, in addition to a flexible element, along which sliding occurs during expansion or contraction are included in this subclass.

SEE OR SEARCH CLASS:

92,	Expansible Chamber Devices, subclasses 34+ for a bellows type expansible chamber device, and subclasses 90+ for a flexible wall type expansible chamber device.

85.04

Rotating with clutch input or output:

This subclass is indented under subclass 85.03. Subject matter in which the flexible element rotates integrally with one of the driving and driven parts.

SEE OR SEARCH THIS CLASS, SUBCLASS:

85.17+,

for an elastic clutch-actuating member that rotates relative to the clutch input and output.

85.05

And causing purely axial movement:

This subclass is indented under subclass 85.04. Subject matter in which flexing of the flexible element causes a component of the power-transmitting device to move in a first direction along a path that is parallel to the axis of rotation of the driving or driven part.

SEE OR SEARCH THIS CLASS, SUBCLASS:

85.2+,

85.15, and 85.49+, for other actuator configurations for producing axial displacement of a clutch element.

85.06	Including flexible friction discs:
	This subclass is indented under subclass 85.05. Subject matter in which the flexible element includes a pair of flexible discs on which friction surfaces for providing the driving continuity are located, the fluid acting directly on the discs to cause elastic deformation thereof and, thereby, affect the extent of engagement of the friction surfaces with each other.

85.07	Plural oppositely acting elastic operators:
	This subclass is indented under subclass 85.05. Subject matter in which the power-transmitting device includes an additional flexible element on which the fluid acts to cause it to flex and move in a second direction substantially opposite the first direction when the fluid acts on the flexible elements.

85.08

Clutch has flat friction surfaces:

This subclass is indented under subclass 85.05. Subject matter in which the component of the power-transmitting device is a first member having a first planar surface and the power-transmitting device includes a second member having a second planar surface parallel to the first planar surface, movement of the component in the first direction resulting in engagement of the first and second planar surfaces to transmit power therebetween by friction, the first and second members being drivingly connected, respectively, to the driving and driven parts.

SEE OR SEARCH THIS CLASS, SUBCLASS:

85.23+,

for a clutch having flat friction surfaces that is operated by a fluid-pressure actuator other than an elastic actuator.

85.09	More than two friction elements:
	T