The present invention relates generally to internal combustion engine flywheel assemblies, and more particularly, to a clutch wear-compensating compound flywheel assembly self-adjusting to compensate wear on a power-train engaging clutch disc in installation in a motor vehicle.
The flywheel is provided at the head of the vehicle power train so as to smooth fluctuations in engine torque. The torquing power of the engine transmitted to the flywheel is in turn transmitted to the transmission of the power train through engagement of a clutch assembly clutch disc with the flywheel.
A friction facing against which the clutch disc is pressed is machined on the flywheel, to which a clutch cover assembly for pressing the clutch disc against the friction facing is peripherally mounted. The clutch cover assembly mainly comprises the clutch cover mounted onto the flywheel, a pressure plate for clamping the clutch disc between itself and the flywheel, and a diaphragm spring for pressing the pressure plate toward the flywheel, sandwiching the clutch disc therebetween.
In clutch cover assemblies thus constructed, set load characteristics of the diaphragm spring will vary with the degree of deflection (relative to the height at which the diaphragm spring is retained in clutch engagement). As the clutch disc wears, therefore, the deflection varies, such that the diaphragm spring urging force pressing the clutch disc against the flywheel varies. Consequently, this can lead to operational deficiencies. For example, clutch pedal resistance may increase, or clutch slippage may occur.
Therefore, a mechanism has been proposed (in Japanese Patent Application Laid-Open No. 27092/1988) for adjusting according to clutch disc wear the height at which the diaphragm spring is retained in the clutch cover assembly in order to maintain constant pressure on the clutch disc in engagement. Such an adjusting mechanism, provided lateral of the clutch cover assembly, has disadvantages in that it conventionally is structurally very complex, or it does not operate accurately enough to be practicable.