Abstract: A torsion damping apparatus between the crankshaft of the engine and the input shaft of the change-speed transmission of a motor vehicle has two flywheels one of which is driven by the crankshaft and the other of which drives the input shaft by way of a friction clutch which generates heat. In order to prevent the transfer of heat from the friction clutch to the antifriction bearing between the flywheels, which are rotatable relative to each other against the opposition of a damper, the bearing is at least partially surrounded by a thermal barrier of synthetic plastic, ceramic or metallic material which prolongs the useful life of the bearing and enhances the torsion damping action of the damper. The thermal barrier can constitute or form part of the damper.

Abstract: A torsion damping assembly which is installed between the crankshaft of the engine and the input element of the change-speed transmission in a motor vehicle has two coaxial flywheels one of which is driven by the crankshaft and the other of which can transmit torque to the transmission in response to engagement of a friction clutch. The transmission of torque between the two flywheels takes place by way of a damper and a slip clutch which latter is effective only within a selected range of possible angular movements of the two flywheels relative to each other.

Abstract: A friction clutch whose diaphragm spring has equidistant prongs extending axially and radially from the energy-storing annular main section and being bolted directly to the flywheel on the crankshaft of an engine so that the spring normally biases a pressure plate against a clutch disc and the latter is thereby biased against the flywheel. The spring has alternating tongues and slots extending radially inwardly from the annular main section as well as an annulus of arcuate openings between the outermost portions of the slots and the prongs. The openings enhance the flexibility of the conical frustum which is constituted by the annular main section and the tongues with reference to the conical frustum including the prongs, and the openings thus prolong the useful life of the diaphragm spring.

Abstract: A diaphragm spring wherein the circumferentially complete outer marginal portion surrounds an annulus of holes constituting the enlarged outer portions of closed slots whose narrower inner portions extend inwardly toward but short of the tips of prongs which surround the central opening of the spring and are separated from one another by radially outwardly extending open slots overlapping the inner portions of the closed slots so as to establish an undulate circumferentially complete annular tension spring radially inwardly of the marginal portion. Each pair of neighboring open slots can flank one or more closed slots. The diaphragm spring can be used in single- or multiple-disc friction clutches.

Abstract: A multiple-disc friction clutch wherein two axially movable pressure plates are disposed between two clutch plates and flank a diaphragm spring whose circumferentially complete outer marginal portion engages one of the pressure plates and which has a second portion located radially inwardly of the marginal portion and engaging the other pressure plate. The second portion of the diaphragm spring has a circumferentially complete tension spring which stores energy in addition to that stored in the outer marginal portion. The tension spring is located radially inwardly of the regions where the second portion engages the other pressure plate.

Abstract: A friction clutch wherein a diaphragm spring is installed between two ring-shaped seats intermediate an axially movable pressure plate and a cover and has a circumferentially complete outer marginal portion extending beyond the seats and engaging with projections of the pressure plate. The spring has a radially innermost portion formed by an annulus of prongs whose tips surround an opening and which alternate with radially outwardly extending open slots. Such open slots alternate and overlap in part with the inner portions of closed slots whose outer portions are holes forming an annulus inwardly of the outer marginal portion. The regions of overlap between the open and closed slots include bridges which together constitute an annular tension spring enabling the diaphragm spring to store energy in addition to that which is stored in the outer marginal portion. The diaphragm spring can be tilted between the seats by a release bearing which cooperates with the tips of the prongs.

Abstract: A diaphragm spring whose outer marginal portion is a circumferentially complete annulus and whose inner marginal portion surrounds a centrally located opening and is formed with a set of radially extending prongs directly surrounding the opening and separated from each other by relatively short radially extending inner slots. The inner marginal portion is further formed with relatively long radially extending outer slots each of which is spaced apart from and registers with one of the inner slots and has an enlarged outer end portion inwardly adjacent to the outer marginal portion. Still further, the inner marginal portion has radially extending elongated closed slots which alternate with pairs of aligned inner and outer slots and each of which partially overlaps the adjacent inner and outer slots.