Abstract: A clutch plate comprises a plate body having a hub and a driven plate which is connected to the plate body through compression springs to rotate with it and extends radially beyond the plate body. A ring-shaped friction lining is secured on the driven plate by rivets, the head of which are sunk into the friction lining. The friction lining is made up of two layers of friction material, and underneath layer riveted to the driven plate and an upper layer stuck onto the lower layer of friction material to cover its whole surface.

Abstract: A liner support disc for supporting friction liners, adapted to constitute a clutch friction wheel, especially for a motor vehicle, of the kind comprising a central portion and a peripheral portion divided into radial blades for receiving the friction liners, with each of the blades being joined integrally to the central portion through a foot, and comprising at least one support zone which is generally parallel to the mean plane of the central portion, for contact with at least one of the friction liners and for fastening of the latter. In a clutch friction wheel, the liners lie on either side of the peripheral portion.

Abstract: A clutch plate with a torsional vibration damper has a hub for non-rotational mounting on a transmission shaft, a driving plate and a cover plate held at a fixed axial distance from the driving plate by means of a multiplicity of spacer bolts, whereby the driving plate is penetrated by a multiplicity of fastening elements, each of which is engaged at the base of the lining spring segments. For the purpose of connecting to the driving plate, there is a single fastening element and a rotational locking mechanism which interacts with it for each lining spring segment, whereby one of these two function elements acts as a spacer bolt.

Abstract: The present invention relates to a clutch assembly having an axial series of friction plates for selectively transmitting torque and rotation between drive and driven assemblies. Specifically, a clutch assembly is provided that, in accordance with the present invention, transmits torque between friction plates and annular portions of rotational members having interengaging, polygonal cross-sectional configurations. The clutch also includes plastically deformable tabs for retaining the axial series of friction plates within a clutch housing. As constructed and arranged, the clutch of the present invention is suitable for high stresses and maximizes clutch efficiency.

Abstract: A continuous slip bypass friction clutch for a hydrokinetic torque converter has annular interfaces that are adapted to engage and transmit torque while rotating in one direction and continuously slipping. One of the interfaces is provided with circuitous grooves that traverse back and forth across essentially the entire width of this interface to channel hydraulic fluid in the torque converter from a high pressure cavity at an outer diameter of the interfaces past the engaged clutch interfaces through flow paths defined thereby to a low pressure cavity at an inner diameter of the interfaces to thereby wet essentially the entire interface area of the clutch and to cool the clutch with a viscous pumping action that augments cooling differential pressure hydraulic fluid flow induced through the flow paths.

Abstract: An improved railway brake shoe member characterized by longitudinally tapered sidewalls of the brake shoe that provide adaptive response to braking under conditions of mis-alignment between the brake shoe member and the tread of a railway car wheel by facilitating wear-in of the mis-aligned brake shoe, thereby assuring brake shoe/wheel tread engagement and accordingly alleviating degradation of braking efficiency and undesirable thermal inputs to the wheel flange that otherwise results from such brake shoe mis-alignment.

Abstract: The invention relates to a reinforcement device for reinforcing the open slots of a carbon brake disk. According to the invention, each slot is provided both with a U-shaped insert whose two lateral limbs are disposed to face the lateral faces of the corresponding coupling bar, and with two channel-section caps that extend towards each other so as to surround the two lateral limbs of the insert completely, each cap having a free end edge that occupies a plane that is parallel to the corresponding inside face and that, on initial assembly, stands slightly projecting relative to said face, thereby enabling said free end edge to be brought exactly into the plane of said inside face after the brake has been used during a running-in period.

Abstract: A friction clutch for a transmission of a motor vehicle generally will have a clutch disc, and the clutch disc will be provided with friction linings for engaging the friction clutch with a rotating engine flywheel. The friction rings can be provided, on both surfaces thereof with trough-shaped depressions, to reduce the weight of the clutch disc. The trough-shaped depressions can essentially be rectangular or square, with rounded corners and with connecting surfaces which are steeply diagonal, or curved with a large radius of curvature.

Abstract: A friction material facing and carrier assembly (10) for a clutch driven plate in which at least one annular friction facing (20A) is secured to the carrier (11) by stripes (24A, 24B, 24C, 24D) of adhesive elastomeric material which are coaxial with the facing. The carrier plate includes circular rows (15, 16, 17) of perforations (14) and the stripes of adhesive are located on the circular lands (25, 26, 27, 28) either side of and between adjacent rows of perforations. The stripes of adhesive may be joined together to provide a continuous stripe of adhesive which extends from the radially inner margin of the facing to the radially outer margin of the facing.

Abstract: A friction member having a high frictional force, a small frictional force fluctuation and excellent wear resistance, which is composed of a substrate coated with a friction material comprising a phenolic resin, 5 to 20% by weight, based on the weight of the friction material, of at least one heat-resistant fiber selected from the group consisting of carbon fiber and aromatic polyamide fiber, 10 to 50% by weight, based on the weight of the friction material, of a solid lubricant and 5 to 30% by weight, based on the weight of the friction material, of at least one wear resistant material selected from the group consisting of Al.sub.2 O.sub.3, SiC and Si.sub.3 N.sub.4, and if necessary, 5 to 20% by weight, based on the weight of the friction material, of at least one soft organic compond selected from the group consisting of a fluorine-containing organic compound and a silicon-containing organic compound.

Abstract: A wet-type friction clutch having universally shaped friction segments manufactured from a nearly scrapless process. Relative juxtaposition of the segments will achieved desired amounts of cooling fluid flow into and out of the friction discs with corresponding desired levels of hydrostatic pressure buildup between the discs.

Abstract: A wet type clutch which has its piston moved by the difference of the pressure in two oil chambers at the two sides of the piston while shutting the communication between the two oil chambers with a friction member adhered to either of the piston or a front cover to be engaged by the piston. An annular groove for communicating with such one of the two oil chambers as will take a lower pressure when the clutch is applied is formed in the surface, to which the friction member is adhered, and/or the adhered surface of the friction member itself, to reduce the pressure acting to return the piston. A seal or high porosity material may also be used to reduce the oil pressure acting on the piston.

Abstract: A conventional circular friction disk having a metal backing plate and outer layer of friction material is replaced by a disk having a plurality of straight outer side edges joined by curved edges, in order to effect material savings in the manufacturing process, and without significant loss in performance.

Abstract: A coupling disc (e.g., the armature or rotor) of an electromagnetic coupling such as a clutch or brake is formed with a plurality of concentric rows of specially shaped slots which are filled with high magnetic reluctance brazing material in order to structurally strengthen the disc and reduce the tendency of the disc to deflect and bend under high loads. Optionally, an annulus of the brazing material may interconnect the rings and may back and support the non-working face of the disc to further strengthen the disc.

Abstract: In a wet-type multi-plate frictional clutch assembly, clutch plates are prevented from being mounted inversely to a clutch hub or a clutch drum to assure proper assembly. Splines formed may be on the periphery of an inner drum or the clutch hub asymmetrically with respect to any diameter of the cross section of the inner drum or the clutch hub perpendicular to the axial direction. Teeth of the passive clutch plates or the drive clutch plates may be designed to properly orient the clutch plates by engaging with the splines.

Abstract: A clutch brake having at least a first section and a second section, a central opening and a generally annular friction surface facing a braking mechanism and to selectively engage the braking mechanism for braking rotation of the shaft. Tabs and recesses selectively interconnect the first and second sections together. The first and second sections are selectively positionable in a disconnected configuration in which the annular friction surface is discontinuous and the sections are movable in a generally radial direction relative to the shaft, and an interconnected position in which the friction surface is substantially continuous and the first and second sections enclose the shaft in the central opening and are held from substantial radial motion relative to the shaft. Whereby, the clutch brake may be installed on the shaft without disconnecting the shaft from the transmission or the engine. A method of attaching the clutch brake to the shaft is further disclosed herein.

Abstract: A driver plate for a torsion-suspended clutch plate of a motor vehicle friction clutch includes an annular disk-shaped lining support (1) composed of a plurality of segments (17), in the form of stamped sheet metal parts, and a reinforcement part (5), provided with windows (13) for receiving springs (15) of a torsion spring system of the clutch disk. The outer circumference of the reinforcement part forms a centering edge (21) to which the segments (17) are welded, resting against it with inner arc-shaped concave contact edges (19). The segments (17) can be produced with a comparatively small amount of stamping waste. The contact edge (19) of the segments (17) can have comparatively rough tolerances, if the openings (11) required for fastening of the friction linings are cut into the lining support (1) after the welding process.

Abstract: A clutch plate wherein a hub carries and is surrounded by a disc which, in turn, carries and is surrounded by an annulus of pairs of partially overlapping resilient sector-shaped carriers for two annular friction linings. The carriers are disposed axially between the friction linings and each such carrier has a flat portion as well as a set of substantially radially extending tongues which are partly cut out and project from the flat portion. The friction linings are fastened to the carriers by stepped rivets, and such rivets further serve to fix the carriers of each pair to each other in axially stressed condition.

Abstract: A synchronizer ring and a manufacturing method thereof having an object to reduce the manufacturing cost and to improve its durability. Therefore, the synchronizer ring according to the invention includes a coating formed by thermal spraying of wear-resistant material on a conical surface of the synchronizer ring body which has been subjected to mechanical machining, pressing a conical jig having a predetermined opening angle against the coated surface in a manner to exert a surface pressure of 4 to 40 N/mm.sup.2 on the coated surface, and rotating the conical jig in a range of 45 to 590 degrees, to thereby make the heights of projections of the surface of the coating uniform.

Abstract: A viscous coupling apparatus having enhanced torque progression characteristics. The viscous coupling apparatus includes two sets of viscous coupling plates which are interleaved and mounted with rotatable members for relative rotation therebetween. Each plate is a generally circular ring of thin plate material and has one or more openings formed therein. The openings include coined edge surfaces that form an inclined surface and an arcuate wiping surface. The coined edges of inner and outer coupling plates oppose one another and facilitate the removal of viscouse fluid from in between and wiping of viscous fluid from the surface of adjacent coupling plates when relative rotation and frictional contact occurs between adjacent plates without generating excessive wear on either one of the plates. The removal of the viscous fluid promotes enhanced frictional contact between the facing adjacent plate surfaces and results in an increased torque transmission characteristic.

Abstract: A friction pad for use in a friction engagement device such as a brake or clutch. The friction pad includes a friction lining, a sensor and an actuator. The sensor senses an operating condition such as pressure applied to the friction lining and emits a signal that is directly or indirectly sent to the actuator. The actuator changes shape in response to the signal and thereby causes a change in the structure of the friction pad.

Abstract: The invention relates to a friction lining of a clutch plate which is constructed with an encircling reinforcing ring to increase the stability of speed. This annular part is arranged outside the wear volume and has a considerably smaller radial dimension than the friction lining.

Abstract: An electromagnetic clutch in which an annulus of sound damping material is sandwiched between an armature disc and a backing ring. The annulus and the backing ring coact to define a constrained-layer damping system for reducing noise when the armature disc is snapped into engagement with the rotor of the clutch and also during slipping and disengagement of the armature disc.

Abstract: A friction lining is designed in particular for clutches and plate-type disc brakes and has an annular body of friction material of which one face forms a friction surface. The annular body has holes distributed around its periphery for the passage of rivets. The holes designed to receive the rivets are arranged in the annular body clear of the friction surface and accordingly do not reduce the area of the friction surface.

Abstract: A clutch friction wheel for a motor vehicle clutch comprises a support having slotted lobes projecting radially from an inner portion of the support. Friction pads are arranged back-to-back on either side of each lobe. Springs are interposed between two associated friction pads. The springs consist of profiled fins such as to define a wavy support having, for contact with one friction pad of each pair, a central zone having free circumferential end portions, and, for contact with the other friction pad of the same pair, marginal portions. One of these marginal portions projects from and is integral with the inner portion of the support.

Abstract: A clutch and disc brake friction assembly is provided for use on medium and heavy duty vehicles and includes a metallic shoe having an exposed backing surface provided with a plurality of relatively spaced protuberances projecting therefrom. A sheet metal attachment lamina overlies the backing surface and is provided with a plurality of holes through which the protuberances extend. Subsequent to the distal ends of the protuberance having passed through the holes, they are enlarged thereby affixing the attachment lamina to the backing surface. The attachment lamina has a plurality of openings relatively arranged to form a grid-like configuration. The openings are separated from one another by narrow elongated segments each having a V cross-sectional configuration with the sides thereof diverging from the shoe backing surface. A high temperature adhesive lamina overlies the backing surface and the divergent sides of the narrow elongated segments of the attachment lamina.

Abstract: A viscous coupling apparatus having enhanced torque progression characteristics. The viscous coupling apparatus includes two sets of viscous coupling plates which are interleaved and mounted with rotatable members for relative rotation therebetween. Each plate is a generally circular ring of thin plate material and has one or more openings formed therein. The openings include coined edge surfaces that form an inclined surface and an arcuate wiping surface. The coined edges facilitate the wiping and removal of viscous fluid from the surface of an adjacent coupling plate when relative rotation and frictional contact occurs between adjacent plates without generating excessive wear on one of the mating plates. The removal of the viscous fluid promotes enhanced frictional contact between the facing adjacent plate surfaces and results in an increased torque transmission characteristic.

Abstract: There is disclosed a frictional member, or ring, which is substituted for the conventional friction linings and marcel of an automotive clutch. The frictional ring is preferably a monolithic member which has recesses that receive support brackets which attach the frictional ring to the clutch disc. Preferably, the frictional ring includes spring biased islands which permit a phased or progressive engagement of the disc between the pressure plate and flywheel.

Abstract: A friction liner for a motor vehicle clutch friction plate comprises a metallic support plate overlaid with a pad of friction material. The surface of the metallic support plate on which the pad of friction material is overlaid is smaller than the working surface of the pad, thus reducing the detrimental effects of deformation of the friction liner resulting from its heating.

Abstract: Wet-type friction members in an automatic transmission are provided with sets of grooves which diverge from each other, or with grooves which increase in width as they approach an edge of the frictional surface and which are rearwardly inclined in relation to the direction of rotation of the member which engages the grooved frictional surface. The grooves facilitate the removal of the oil film which is formed on the frictional surface, and thereby improves torque transmission and speeds engagement. In addition, the presence of the specially configured grooves causes the coefficient of friction to decrease gradually as relative rotational speed decreases, and avoids a sudden increase in the coefficient of friction as engagement is completed.

Abstract: A friction disc (110) includes a pair of segmented friction facings (112) adhered to the opposing sides of annular core (114). The friction facings (112) are composed of three arcuate segments (116) of sintered material or paper impregnated with a resin interjoined together at match lines (118) located generally 120.degree. apart. Each arcuate segment (116) includes opposed ends having tab and slot configurations which are designed to have a pair of arcuate edge lines (124, 126), (124', 126') located in an opposed relationship proximate the annular centerline of the width of the segment (116). An interconnector edge line (128), (128') is located angularly across the annular centerline of the segment (116) and joined tangentially to the arcuate match lines (124, 126), (124', 126'). The remaining end of each arcuate match line (124, 126), (124', 126') is then joined to the respective inside annular edge (134) and outside annular edge (136) of each arcuate segment ( 116).

Abstract: A friction disc paddle for a rotatable clutch disc has powdered metal friction faces compacted directly on each face of a metal substrate. The friction faces extend through apertures in the metal substrate, and extend to the circumferential and radial edges of the metal substrate. The friction faces are solidly bonded to the metal substrate. The apertures not only ensure that the friction faces are securely attached to the metal substrate, but they also reduce the overall weight of the friction disc paddle.

Abstract: A rotor for a six-pole electromagnetic clutch includes an outer pole ring and an axially facing disc. The disc is formed with two circumferentially extending and radially spaced rows of circumferentially spaced slots, there being short circumferentially extending bridges between adjacent slots in each row. To strengthen the bridges against failure under high load and heavy wear conditions, a stainless steel reinforcing ring is brazed to the outer pole ring and the disc and transmits torque between the two. The outer edge of the disc thus may be spaced radially inwardly from the outer pole ring to establish an annular air gap which coacts with the two rows of slots to enable the rotor to possess the requisite magnetic characteristics to function in a six-pole clutch.

Abstract: A motor vehicle clutch disc includes a metal carrier sheet; an elastomer intermediate layer facing the metal carrier layer; a clutch lining facing the elastomer intermediate layer; and a composite binder bonding first surface regions of the elastomer intermediate layer to the metal carrier sheet and to the clutch lining by chemical sorption. Areas of the first surface regions are less than areas of the metal carrier sheet and the clutch lining facing the elastomer intermediate layer. The elastomer intermediate layer is of hydrated nitrile rubber or a fluoroelastomer. The elastomer intermediate layer has an elasticity of non-linear spring characteristics and is effective in a direction perpendicular to the plane of the clutch disc. The elastomer intermediate layer has unbonded, second surface regions facing the metal carrier sheet and the clutch lining.

Abstract: A disc brake assembly having enhanced brake efficiency and improved cooling includes a brake pad having arcuate upper and lower edges and a width that diminishes along its length from its leading edge to its trailing edge. A braking force is exerted on the brake pad by plural hydraulic actuators having pistons aligned with longitudinally spaced portions of the brake pad. The radial and circumferential locations of such portions are selected to minimize differences in the radial wear of the brake pad. The actuators are preferably symmetrically positioned with respect to a brake rotor centerline but may be positioned asymmetrically. The actuator pistons are confined for movement within close tolerances in order to limit the angle though which the brake pads can rock.

Abstract: A friction material facing (20) and carrier (11) assembly in which the facing (20) is secured to the carrier (11) by a plurality of concentric circular stripes (24A, 24B, 24C) of adhesive (24). Each stripe (24A, 24B, 24C) is interrupted at a single point on the circle to form a gap (25A, 25B, 25C) between the beginning and end of each circle of adhesive. The end of one circle may be joined to the beginning of the adjacent circle so as to form a continuous stripe of adhesive (24) from the inner margin to the outer margin of the facing (20).

Abstract: A friction clutch driven plate (10) having a hub (11) and friction facings (14, 15) which face in opposite directions. The friction facings are mounted on respective coaxial annular carrier plates (16, 17) which are rotatable about the hub (11) and are secured back to back with each other by the stop pins (22) which pass through aligned holes (26, 27) in the two carrier plates (16, 17). The holes (27) in at least one carrier plate (17) being enlarged to enable that carrier plate (17) to move rotationally relative to the other carrier plate (16), said relative rotation being resisted by springs (28) acting between the two carrier plates.

Abstract: A multi-layer friction element is disclosed consisting of carbon-carbon composite material comprising a structure layer of so-called "coarse" texture comprising segments of rovings and at least one friction layer of so-called "fine" texture comprising fibre segments. A method also is disclosed for producing the friction element by preparation of a fibrous substrate by introducing segments of roving and/or fibers into a mould preferably by means of a distribution apparatus. Further disclosed is an apparatus for automatically obtaining a fibrous substrate of predetermined texture.

Abstract: An electromagnetic clutch rotor has an axial end plate with a plurality of concentric rings formed therearound. Each concentric ring is defined by a plurality of alternating arcuate slits and ribs. Arcuate slits form poles on opposite sides thereof, and cause the magnetic flux to follow a zigzagging path between the axial end plate and the armature plate. The ribs on adjacent concentric rings are not aligned radially, and thus reduce the amount of flux leakage through the axial end plate. In addition, the ribs are progressively larger towards the radial center to account for the increased bending stresses towards the center of the axial end plate.

Abstract: A viscous coupling apparatus having enhanced torque progression characteristics. The viscous coupling apparatus includes two sets of viscous coupling plates which are interleaved and mounted with rotatable members for relative rotation therebetween. Each plate is a generally circular ring of thin plate material and has one or more openings formed therein. The openings include coined edge surfaces that form an inclined surface and a planar wiping surface. The coined edges facilitate the wiping and removal of viscous fluid from the surface of an adjacent coupling plate when relative rotation and frictional contact occurs between adjacent plates without generating excessive wear on one of the mating plates. The removal of the viscous fluid promotes enhanced frictional contact between the facing adjacent plate surfaces and results in an increased torque transmission characteristic.

Abstract: An overhang type electromagnetic clutch used for selectively connecting the rotation of an internal combustion engine to a compressor for an air conditioning system for an automobile. The clutch is provided with a rotor having a sliding surface axially spaced from an outer end of a pulley arranged around the rotor. A bit, which initially is in contact with the sliding surface at a location spaced from the axis of the rotation of the rotor, is radially moved while the rotor is rotated, so that radially spaced apart tool marks eccentric to the axis of the rotation of rotor and having a gradually increased radius are formed on the entire region of the sliding surface. An increased engagement of the sliding surface with an armature is obtained due to the provision of engagements in the circumferential direction.

Abstract: A friction pad for use in a friction element used in a friction engagement device such as a brake or clutch. The friction element includes a carrier and a plurality of friction pads circumferentially spaced about the carrier. The pads may have a modular construction whereby pad portions are releasably secured to support portions. The pads may also be releasably secured to the carrier. Various friction pad constructions are contemplated including constructions in which the secondary support portion includes a membrane and the primary support portion includes a cylindrical member extending between the membrane and the friction pads. A continuous friction pad ring may be substituted for the discrete friction pads. The carrier may be provided with locator pins in the pad receiving bores to orient the pads properly. The carrier may have cuts and grooves formed therein to provide a flexible or even beam mounted support for the friction pads.

Abstract: A friction facing material and carrier assembly (2) to form a part of a driven plate of a friction clutch. The assembly (2) comprises a circular carrier plate (4) with resilient flexible paddles (14) at its periphery. Two annuli of friction material constituting friction facings (20,22) are each bonded by silicone rubber to opposite sides of the paddles. The silicon rubber on each side of the paddles is in the form of substantially continuous circular concentric strips of rubber substantially centered on axis (X) about which the assembly (2) is intended to rotate. The concentric strips (24A, 24B, 24C, 24D, 24E), bonding the friction facing (20) to one side of the paddles (14), are each preferably opposite the gap between two adjacent concentric stripes of rubber bonding the friction facing (22) to the other side of the paddles.

Abstract: A single disc, single acting brake or clutch has one or more pneumatically actuated piston and cylinder assemblies for urging friction material into contact with a disc that is rotatable relative to a body which carries the piston and cylinder assembly.

Abstract: A groove pattern for the paper-based annular friction facing (38) on an alar plate (39) of a clutch plate (41) of a wet clutch to equalize the surface temperature of the friction facing and thus increase the thermal capacity of the clutch where there is continuous slippage. The groove pattern includes one or more continuous annular grooves (42,43,44,45) dividing the friction area into at least three annular bands (46,47,48,49,50), an inner band (46), at least one intermediate band (47,48,49), and an outer band (50), and a plurality of cross grooves (51,52) in each band which are angled with respect to a radius of the facing. The angled cross grooves extend at an acute angle (a,b) (10-60 degrees) to such radius. Slip of the friction pair of plates causes a viscous pumping action. The cross groove angle in each band of the facing is similar so as to keep all the grooves filled with cooling oil, and the cross-section of the cross grooves vary in their dimensions as between the bands.

Abstract: A friction disc comprises a circular clutch plate with a plurality of friction liners distributed around the clutch plate coaxially with the latter. Each friction liner is retained on the clutch plate, and comprises two pads. One of these pads is on one side of the clutch disc, and the other pad is on the other side. At least one of the pads of each friction liner has a rolling surface for engagement with the corresponding side of the clutch disc, such that the pad concerned is able to tilt with respect to the clutch plate.

Abstract: The invention relates to friction pairs of machine parts.A friction element of a friction pair comprises a three-dimensional framework (1) embedded in a matrix (2) in the zone of the friction surface (4).The framework (1) is made from a wear-resistant material and the matrix (2) from a material with high heat conductivity coefficient. The framework (1) has a cellular shape formed by a honeycomb structure, a corrugated strip and the like. The framework rises partially above the surface of the matrix forming, together with the latter, a friction surface (4) possessing a regular microrelief. The area of the framework (1) rising above the matrix (2) diminishes proportionally in the direction from the maximum load zone towards the minimum load zone.The invention can be used in braking mechanisms, in particular in brake disks and drums of passenger cars, in disks of friction clutches and the like.

Abstract: The present specification discloses a wheel comprising a central hub and an outer rim interconnected by a web. A pair of annular braking discs are mounted one on each side of the web, each annular braking disc being secured to the web by at least two attachment elements. Each annular braking disc comprises at least two curved segments, each curved segment having two end edge regions, each end edge region of each segment overlapping an end edge region of an adjacent segment so that a continuous annular braking disc with a smooth braking surface is provided. The overlapping end edge regions have sections which extend generally axially of the braking disc in opposite directions, the sections interengaging with each other, with a spring being located between the overlapping end regions to thus bias the overlapping end regions circumferentially with respect to the annular braking disc, to thus securely interengage the segments.

Abstract: A backing plate for connection to a clutch disc includes a pair of spaced friction material portions (or pads). A central channel extends between the two portions to allow air to flow over and cool a central area of the friction material. Clearances are defined at radially inner and outer areas of the channel and receive rivets to secure the backing plate to a clutch disc. The rivets are positioned radially between the radially inner and radially outer edge of the friction material, such that the backing plate is firmly secured to the clutch disc to prevent bowing. The improved backing plate ensures that the backing plate remains firmly secured to the clutch disc, and that the friction material is adequately cooled such that it efficiently transmits rotational forces from a drive source to a driven shaft.

Abstract: A friction clutch including a flywheel and a pressure plate which frictionally engage the driven disc assembly during use is disclosed. A pair of friction rings are mounted respectively on the flywheel and the pressure plate for engaging the driven disc assembly therebetween. Each of the friction rings includes a rigid backing plate having a first friction element secured to one face thereof and a second friction element secured to opposite face thereof. The first friction elements are formed from a material having a relatively low coefficient of friction, while the second friction elements are formed from a material having a relatively high coefficient of friction. Retainers are provided for retaining the friction rings to the flywheel and the pressure plate, while permitting restricted relative rotational movement therebetween.