Abstract: In a friction disc clutch assembly of the type including a flywheel secured to a drive shaft, a clutch cover having an outer peripheral rim secured to the flywheel by means of a plurality of circumferentially spaced bolts and being formed with an internal cylindrical surface, a pressure plate mounted within the clutch cover in such a manner as to be rotatable with and axially displaceable with respect to the flywheel, a diaphragm spring assembled within the clutch cover to bias splined to a driven shaft and interposed between the flywheel and the pressure plate, the outer periheral rim of the clutch cover is formed with a radial exhaust hole located between each pair of the circumferentially spaced bolts and extending outwardly from the internal cylindrical surface of the clutch cover to exhaust muddy water entered into the interior of the clutch cover.

Abstract: A clutch disk of the type having a hub and a clutch plate operatively connected by at least two endless elastomer belts, each of which is entrained over a pair of bushings, one of which is mounted on a hub pin attached to the hub and the other of which is mounted on a plate pin attached to the clutch plate. Each of the bushings is defined by a semicylindrical side wall and a pair of flat side walls adjacent to the semicylindrical side wall and extending parallel to each other. Opposite belt runs of the elastomer belt act on the flat side walls of the bushing to forcibly rotate the bushing around the pin.

Abstract: Disclosed herein is a clutch disc comprising a thrust plate incorporated between the first frictional plate, which is interposed between the subdisc plate and the hub flange, and the hub flange, so as to rotate relatively to the hub flange within the range of slight angular displacement corresponding to the amount of play defined between the pawl portion of the thrust plate and the cutaway portion of the aperture opened through the hub flange, and a frictional plate fixed to the thrust plate on the flange side, said frictional plate having a smaller frictional coefficient than the first frictional plate.

Abstract: In an hydraulic release mechanism for a vehicle clutch, a seal member is adapted to a transmission housing assembly to surround an extended portion of a push-rod in a fluid tight manner, and an hydraulic cylinder includes a cylinder housing provided at its closed end with a port for connection to a source of hydraulic pressure and being detachably secured to the housing assembly at its open end to contain one end of the push-rod therein, and a piston axially slidable within the cylinder housing through an annular seal member to subdivide the interior of the cylinder housing into a pneumatic chamber in open communication with the atmospheric air and an hydraulic chamber in open communication with the port, the piston being engaged with the one end of push-rod to urge the push-rod toward a release member of the vehicle clutch.