Abstract: An actuation module of a centrifugal clutch incorporates a plurality of actuating weights mounted on pivot links. The weights pivot radially outwardly under centrifugal forces induced by rotation of the actuation module. One weight is secured to each of the pivot links, and springs counter the radially outward movements of the weights. Each weight defines a slot; a roller is disposed in each of the slots. Each slot defines a pair of spaced walls; each of the rollers is rotatable on an axle secured between one pair of walls. The rollers engage cam ramps that rotate with the module but are axially displaceable with respect thereto for engagement and disengagement of the clutch. Each pair of walls is oriented in direction of pivotal movement of its associated weight. A roller thrust plate is secured between each roller and the wall of the slot spaced farthest away from the pivot link.

Abstract: A centrifugal master friction clutch having an installation device is provided that includes a cover assembly fixed for rotation with an engine flywheel and at least one friction plate fixed for rotation with a transmission input shaft. The cover assembly includes a pressure plate for applying a clamping force against the friction plate and a plurality of flyweights that rotate outward under the effects of centrifugal force to cause the pressure plate to exert a clamping force against the friction plate. The clutch installation device includes a first member rotatably disposed in the cover assembly radially inward of the flyweights. A portion of the first member is configured to engage at least one of the flyweights to force the engaged flyweight to rotate outward. A second member is included for engagably limiting the degree of rotation of the first member. A method of installing a centrifugal clutch is also described.

Abstract: A clutch travel stop limits the amount of vehicular clutch travel adjustment normally permitted for compensating clutch component wear. The stop is attached to a centrifugal weight and roller clutch actuation module to control the amount of permissible wear of clutch components including, for example, friction plate linings. In one embodiment, the stop is defined by a protuberance, such as an integrally formed radially extending lug integrally affixed to an outer circumferential periphery of the housing of the centrifugal module. The lug is positioned to arrest relative movement between respective flanges of a clutch cover and the centrifugal module to limit adjustment of the clutch so that an over-adjustment condition is avoided. Potential damage to critical clutch components is thereby minimized, such as damage to flywheel and pressure plate components caused by fasteners that become exposed after clutch linings retained by the fasteners to the friction disc have become worn.

Abstract: A centrifugal master friction clutch having an installation device is provided that includes a cover assembly fixed for rotation with an engine flywheel and at least one friction plate fixed for rotation with a transmission input shaft. The cover assembly includes a pressure plate for applying a clamping force against the friction plate and a plurality of flyweights that rotate outward under the effects of centrifugal force to cause the pressure plate to exert a clamping force against the friction plate. The clutch installation device includes a first member rotatably disposed in the cover assembly radially inward of the flyweights. A portion of the first member is configured to engage at least one of the flyweights to force the engaged flyweight to rotate outward. A second member is included for engagably limiting the degree of rotation of the first member. A method of installing a centrifugal clutch is also described.

Abstract: A clutch ramp reaction plate is adapted to be positioned adjacent a centrifugal actuation module of a centrifugally actuated vehicular clutch. The ramp reaction plate includes attached individually machined ramp segments manufactured separately from the ramp reaction plate. In one embodiment, the ramp segments are made from a powdered metal process to assure uniform tolerances. In an alternate embodiment, the ramp segments are formed of hardened stamped steel material. The ramp reaction plate is machined to accept the segments, which includes a surface hardness higher than that of the ramp reaction plate to accommodate wear resistance. The ramp segments can be impregnated with lubricants or polytetrafluoroethylene materials to reduce rolling friction and wear between the ramp surfaces and mass weight rollers of the centrifugal actuation module that interacts with the ramp surfaces. The segments are attached to the ramp reaction plate by means of fasteners including bolts, rivets, or adhesives.

Abstract: A clutch travel stop limits the amount of vehicular clutch travel adjustment normally permitted for compensating clutch component wear. The stop is attached to a centrifugal weight and roller clutch actuation module to control the amount of permissible wear of clutch components including, for example, friction plate linings. In one embodiment, the stop is defined by a protuberance, such as an integrally formed radially extending lug integrally affixed to an outer circumferential periphery of the housing of the centrifugal module. The lug is positioned to arrest relative movement between respective flanges of a clutch cover and the centrifugal module to limit adjustment of the clutch so that an over-adjustment condition is avoided. Potential damage to critical clutch components is thereby minimized, such as damage to flywheel and pressure plate components caused by fasteners that become exposed after clutch linings retained by the fasteners to the friction disc have become worn.

Abstract: A friction clutch having a wear compensation device is provided that includes a cover assembly that is secured to a flywheel of an internal combustion engine for rotation therewith. A pressure plate is arranged in the cover assembly and is urged by a spring member toward the flywheel. At least one friction plate is arranged between the pressure plate and the flywheel enabling the pressure plate to provide a clamping force to press the friction plate against the flywheel. The wear compensation device includes two cooperating annular members that are changeable along their axial dimension to compensate for the increased distance between the pressure plate and the friction plate due to wear in the clutch.

Abstract: A friction clutch for a motor vehicle includes a cover, a pressure plate, a biasing member and an adjustment mechanism. The adjustment mechanism includes a first annular cam, a second annular cam and a torsional spring and housing assembly. The cover has an axis of rotation. The pressure plate is coupled to the cover for rotation therewith about the axis. The pressure plate has a frictional engagement surface substantially normal to the axis. The pressure plate has a plurality of cooling blades extending from the pressure plate on a side opposite the frictional engagement surface. The blades are located at a first radial distance from the axis. The biasing member is interposed between the cover and the pressure plate, and biases the pressure plate toward an engaged pressure plate position. The adjustment mechanism is centered about the axis and is located at a first radial distance from the axis. The adjustment mechanism is operably disposed between the biasing member and the pressure plate.

Abstract: An adjustment mechanism for a frictional clutch for a motor vehicle includes a pressure plate, a first annular cam member, a second annular cam member, a cam spring, a cam control finger, an anti-rotation feature, and a control finger drag spring. The pressure plate has an axis of rotation and an engagement surface substantially normal to the axis of rotation. The first annular cam member is concentric with the axis of rotation and has a plurality of first ramped cam surfaces. The first annular cam member is rotatively fixed with respect to the pressure plate. The second annular cam member is rotatable relative to the first annular cam member and has a plurality of second ramped cam surfaces in engagement with the first ramped cam surfaces. The second annular cam member, together with the first annular cam member, define an effective pressure plate thickness. The second annular cam member also has an engagement step at its outer periphery.

Abstract: A friction clutch for a motor vehicle includes a cover, a pressure plate, a biasing member and an adjustment mechanism. The adjustment mechanism includes a first annular cam, a second annular cam and a torsional spring and housing assembly. The cover has an axis of rotation. The pressure plate is coupled to the cover for rotation therewith about the axis. The pressure plate has a frictional engagement surface substantially normal to the axis. The biasing member is interposed between the cover and the pressure plate, and biases the pressure plate toward an engaged pressure plate position. The adjustment mechanism is centered about the axis and is located at a first radial distance from the axis. The adjustment mechanism is operably disposed between the biasing member and one of the pressure plate and the cover. The first annular cam is rotatably fixed with respect to the pressure plate and the cover. The second annular cam is rotatable relative to the first annular cam.

Abstract: A friction device includes an adjustment mechanism for adjusting the device in response to wear on a friction surface within the device. The adjustment mechanism includes a first cam ring and a second cam ring adjacent the first cam ring. In one embodiment, the first cam ring is adapted for axial, but non-rotational movement with respect to a cover of the friction device, the cover being secured to a driving member for transmitting torque. The second cam ring is adapted for rotational movement with respect to the cover and the first cam ring. The first cam ring has a plurality of annular ramped surfaces on an axial face of the first cam ring. The second cam ring has a plurality of annular ramped surfaces on an axial face opposing the axial face of the first cam ring.

Abstract: A friction device includes an adjustment mechanism for adjusting the device in response to wear on a friction surface within the device. The adjustment mechanism includes a first cam ring and a second cam ring adjacent the first cam ring. In one embodiment, the first cam ring is adapted for axial, but non-rotational movement with respect to a cover of the friction device, the cover being secured to a driving member for transmitting torque. The second cam ring is adapted for rotational movement with respect to the cover and the first cam ring. The first cam ring has a plurality of annular ramped surfaces on an axial face of the first cam ring. The second cam ring has a plurality of annular ramped surfaces on an axial face opposing the axial face of the first cam ring.

Abstract: A friction device includes an adjustment mechanism for adjusting the device in response to wear on a friction surface within the device. The adjustment mechanism includes a first cam ring and a second cam ring adjacent the first cam ring. In one embodiment, the first cam ring is adapted for axial, but non-rotational movement with respect to a cover of the friction device, the cover being secured to a driving member for transmitting torque. The second cam ring is adapted for rotational movement with respect to the cover and the first cam ring. The first cam ring has a plurality of annular ramped surfaces on an axial face of the first cam ring. The second cam ring has a plurality of annular ramped surfaces on an axial face opposing the axial face of the first cam ring.

Abstract: A friction device includes an adjustment mechanism for adjusting the device in response to wear on a friction surface within the device. The adjustment mechanism includes a first cam ring and a second cam ring adjacent the first cam ring. In one embodiment, the first cam ring is adapted for axial, but non-rotational movement with respect to a cover of the friction device, the cover being secured to a driving member for transmitting torque. The second cam ring is adapted for rotational movement with respect to the cover and the first cam ring. The first cam ring has a plurality of annular ramped surfaces on an axial face of the first cam ring. The second cam ring has a plurality of annular ramped surfaces on an axial face opposing the axial face of the first cam ring.

Abstract: A friction device includes an adjustment mechanism for adjusting the device in response to wear on a friction surface within the device. The adjustment mechanism includes a first cam ring and a second cam ring adjacent the first cam ring. In one embodiment, the first cam ring is adapted for axial, but non-rotational movement with respect to a cover of the friction device, the cover being secured to a driving member for transmitting torque. The second cam ring is adapted for rotational movement with respect to the cover and the first cam ring. The first cam ring has a plurality of annular ramped surfaces on an axial face of the first cam ring. The second cam ring has a plurality of annular ramped surfaces on an axial face opposing the axial face of the first cam ring.

Abstract: An improved wear compensation device for manual or automatic adjustment for wear in a spring loaded friction clutch. An annular circumferentially extending cam track on the clutch cover or the adjusting ring or both is used to move the adjusting ring towards the clutch pressure plate when the adjusting ring is turned relative to the cover.

Abstract: A self-adjusting mechanism for a friction clutch of the type having movable pressure plate, adjusting ring, release sleeve, and release lever having ends engaging adjusting ring and release sleeve with intermediate point on release lever engaging pressure plate. Release yoke is engagable with release sleeve to move release sleeve away from pressure plate, release yoke having a selected free play distance between unengaged and engaged positions with respect to release sleeve, free travel distance decreasing as friction surfaces wear. Mechanism includes: sensing mechanism to sense a decrease in free travel distance as engagement occurs and adjusting mechanism responsive to sensing mechanism to cause adjusting ring to advance toward pressure plate as disengagement subsequently occurs, compensating for decrease in free travel distance.

Abstract: A drive assembly is adapted for engagement with a driven clutch plate of a heavy-duty truck. The drive assembly incorporates a drive pin comprising a shank inserted into a flywheel, and a spindle which extends radially inwardly from the flywheel. A drive head is rotatably mounted on the spindle, which incorporates a groove containing a compressible friction ring for assuring frictional retention of the head. The drive pin includes a shoulder situated intermediate shank and spindle, the shoulder incorporating a frustoconical portion to provide a tapered bearing surface for rotatably supporting the drive head on the spindle. The shoulder also contains a radially extending annulus which faces the shank, the annulus adapted for limiting depth of insertion of the shank into the flywheel. In the same preferred form, the drive head has a tapered counterbore to matingly engage the frustoconical portion, and also contains a plurality of chamfered surfaces adjacent opposed ends of the head.

Abstract: A clutch brake is formed from a pair of identically shaped semi-annular halves. One end of each of the halves is formed with a first circumferentially extending protrusion located near the outer circumferential edge thereof. Each of the opposite ends of the halves is formed with a second circumferentially extending protrusion located near the inner circumferential edge thereof. The outer protrusions are disposed adjacent to the inner protrusions in circumferentially overlapping fashion. A pair of radially extending threaded fasteners are used to secure the two clutch brake halves together. The threaded fasteners extend radially through aligned apertures formed in the overlapping outer and inner protrusions. The radially innermost ends of the threaded fasteners extend a sufficient distance so as to engage splines formed on a transmission input shaft upon which the clutch brake is mounted.

Abstract: A clutch assembly having an annular cover member attached to an engine flywheel, an annular pressure plate which is floatingly attached to the cover member by a plurality of drive straps, a friction drive assembly which is splined to a transmission shaft for rotation therewith and sliding movement therealong, and which is positioned between the pressure plate and the engine flywheel, a plurality of radially extending release levers, each of which is pivotably attached to the cover member at a location between the ends of such release lever, and a belleville spring trapped between the cover member and the release levers to normally bias the release levers so that the outer end of each of them imposes a load on the pressure plate which tends to urge the pressure plate against the friction drive assembly and the friction drive assembly against the flywheel, each of the drive straps having an outwardly projecting extension which is positioned between the pressure plate and the outer end of an adjacent release lev