Patent ID: 6588565
Filing Date: 2003-07-08
Classification: F16D

Abstract:
An engageable and disengageable torque transmitting friction clutch, comprising a housing rotatable about an axis; a pressure plate; means for non-rotatably connecting said pressure plate to said housing with limited freedom of movement in the direction of said axis; a rotary counterpressure plate adjacent said pressure plate; a torque transmitting clutch disc between said plates; at least one diaphragm spring tiltably mounted on an axially fixed seat in said housing and reacting against said housing to bias said pressure plate toward said counter-pressure plate to thereby clamp said clutch disc against said counterpressure plate and to rotate said clutch disc about said axis, said clutch disc having friction linings engageable by and disengageable from at least one of said plates and at least said friction linings being subject to wear as a result of repeated engagement with and disengagement from said at least one plate; an adjusting unit arranged to act between said diaphragm spring and said pressure plate and including means for compensating for said wear at least upon said friction linings to thereby maintain a substantially constant state of elastic deformation of said diaphragm spring, resulting in the application of a substantially constant biasing force upon said pressure plate in the engaged state of the clutch during the useful life of the clutch, said compensating means comprising at least one at least substantially ring-shaped member rotatable about said axis and having ramps extending circumferentially of said at least substantially ring-shaped member and sloping in the direction of said axis, said at least one ring-shaped member being arranged to move in the direction of said axis at a rate corresponding to the extent of said wear at least upon said friction linings in response to movement of said ramps relative to a support for said at least one ring-shaped member during disengagement of the clutch; means for engaging and disengaging the clutch including actuating means movable along a predetermined path to engage and disengage the clutch; and means for varying the torque being transmitted by the friction clutch and/or by the clutch disc, including means for gradually reducing the trans- mitted torque at least during a portion of movement of said actuating means along said path in a direction to disengage the clutch, said adjusting unit being arranged to perform compensating adjustments during disengagement of the clutch and comprising means for limiting said compensating adjustments to an extent that compensates for said wear at least upon said friction linings, even if said adjusting unit is entirely relieved of contact pressure from said diaphragm spring during disengagement of the clutch.