The invention relates to a clutch disc for a friction clutch, in particular of a motor vehicle.
From DE-A-3,340,896(U.S. Pat. No. 4,635,780) a friction clutch disc is known which comprises a hub with a hub disc which projects from the hub radially to an axis of rotation of the hub and with a cylindrical bearing face axially to the side of the hub disc and two lateral discs which are arranged axially on either side of the hub disc. The two lateral discs are rigidly connected to one another to form a unit together with the friction linings of the clutch disc and are rotatable relative to the hub disc about a limited angle of rotation. Each lateral disc has a central opening through which the hub passes. Several springs couple the lateral discs rotatably to the hub disc. A plastics mounting ring which is held non-rotatably in the central opening of a first lateral disc of the two lateral discs guides the two lateral discs on the hub. The mounting ring has the form of an annular disc which rests axially laterally on the lateral disc and from whose internal periphery spring tongues shaped to a cone extend through the central opening in the lateral disc. The spring tongues carry the lateral disc in their base region and lie with their ends under radial tension on a cylindrical bearing face of the clutch disc hub. A mounting ring of this type which can be produced inexpensively holds the lateral discs without clearance on the hub and compensates production tolerances.
It has been found that a mounting ring of the known type can compensate for errors of alignment between gearbox shaft and crankshaft only to a limited extent. In particular, with engine/gearbox constructions in which the gearbox shaft is no longer mounted in a pilot bearing of the crankshaft, as previously the case, relatively great errors of alignment between gearbox shaft and crankshaft can occur and can impair the operation of a torsional vibration damper provided in the clutch disc. Although the basic friction of the torsional vibration damper caused by the known mounting ring is relatively slight, it is still too great for a plurality of applications and detrimentally affects the damping devices of the torsional vibration damper, particularly if errors of alignment between the gearbox shaft and the crankshaft or inclination errors of these shafts occur. With the known clutch disc, the spring tongues lie with their tongue edges on the hub, leading to increased edge pressure, increased wear and differing coefficients of friction. A primary object of the invention is to provide a clutch disc provided with a torsional vibration damper, in which even relatively great errors of alignment between gearbox shaft and crankshaft can be compensated without impairing operation of the torsional vibration damper.