Abstract

A compound flywheel assembly self-adjusting to compensate in operation wear on a clutch disc pressed to an end friction facing of the flywheel assembly by a clutch pressure plate. It comprises a first flywheel peripherally carrying a ring gear via which the assembly is cranked in starting the engine, afforded a certain amount of angular backlash; a second flywheel bearing the friction facing, connected to the first flywheel so as to be angularly fixed yet axially movable relative thereto; a clutch wear-gauging mechanism provided peripherally in an end surface of the first flywheel opposite the peripheral margin of the pressure plate sandwiching the clutch disc; and an adjusting mechanism. Wear on the clutch disc is gauged by the clutch wear-gauging mechanism in contacting the pressure plate peripheral margin meanwhile the pressure plate is pressing the clutch disc against the second flywheel. Rotation of the ring gear through the backlash angle relative to the first flywheel by the engine-starting cranking torque effects radial advancing of the adjusting mechanism, which, by means of inter-flywheel wedging members thereof, in cooperative response to the clutch wear-gauging mechanism, effects axial movement of the second flywheel away from the first flywheel, i.e., toward the clutch disc. The set load on the diaphragm spring pressing the clutch disc through the pressure plate in clutch engagement is maintained constant despite clutch disc wear.