Abstract: A friction disc paddle for a rotatable clutch disc has powdered metal friction faces compacted directly on each face of a metal substrate. The friction faces extend through apertures in the metal substrate, and extend to the circumferential and radial edges of the metal substrate. The friction faces are solidly bonded to the metal substrate. The apertures not only ensure that the friction faces are securely attached to the metal substrate, but they also reduce the overall weight of the friction disc paddle.

Abstract: An internally assisted friction clutch having both engagement springs and assister springs extending between a cover and a release sleeve is disclosed. The radially directed forces exerted by the springs continually center and rotatably drive the release sleeve co-axially relative to the cover under normal operating conditions. In order to prevent excessive relative rotation, a plurality of protrusions are formed on the release sleeve which extend into respective recesses formed on the cover. The recesses are sized to be significantly larger than the protrusions so as to cause engagement only when four to five degrees of relative rotational movement or more occurs between the release sleeve and the cover.

Abstract: A self-contained hydraulic unit is provided for controlling operation of a friction clutch assembly. The hydraulic unit is connected to a source of pressure so that when pressure is applied to the unit it responds to actuate a plurality of levers to engage the clutch. Upon removal of pressure from the hydraulic unit, spring means responds to withdraw the levers and disengage the clutch. The hydraulic unit is non-rotatably supported by the friction clutch assembly and includes an axially fixed member and an axially movable member interconnected by a sliding connection. A piston and diaphragm arrangement is provided between the fixed and movable members so that when pressure is introduced into the diaphragm the piston operates to slide the movable member relative to the fixed member by means of the sliding connection thereby actuating the levers to cause engagement of the clutch.