Patent ID: 6779643
Filing Date: 2004-08-24
Classification: F16D

Abstract:
Friction clutch for a motor vehicle with a thermal engine, of the type comprising a reaction plate (13) intended to be rotationally fixed to a driving shaft, a friction disc (14), carrying friction linings (15) at its external periphery intended to be rotationally fixed to a driven shaft, a pressure plate (12, 112, 212, 312, 412, 712, 912), a cover (11, 911) fixed to the reaction plate (13), axially acting resilient means (16) acting between the cover (11, 911) and the pressure plate (12, 112, 212, 312, 412, 712, 812, 912), the pressure plate (12, 112, 212, 312, 412, 712, 812, 912) being rotationally fixed to the cover (11, 911) whilst being able to move axially with respect to it, an element in the form of one of the reaction plate (13), the pressure plate (12, 112, 212, 312, 412, 712, 812, 912) and the cover (11, 911) including two half-pieces able to be moved axially with respect to each other under the action of a device for taking up the play due to the wear of the friction linings, the play take-up device comprises at least one pair of circumferentially disposed complementary ramps (17, 117, 217, 317, 417; 18, 118, 218, 418) associated respectively with each of the two half-pieces (12A, 112A, 212A, 612A, 712A, 512A, 812A, 912A, 412A, 1012A; 12B, 112B, 212B, 312B, 412B, 712B, 812B, 912B, 1012B), one of the ramps (17, 117, 217, 317, 417) being adapted to move circumferentially with respect to the other ramp (18, 118, 218, 418) in the take-up direction to increase the overall thickness of the element and prevented from moving in the other direction by a unidirectional means (24, 133, 240, 251, 350, 352, 440, 840, 1026), the said circumferential movement being controlled by a release (22, 222, 322, 422, 922, 1022, 462) sensitive to the state of wear of the friction linings (15), one of the ramps (18, 118, 218, 418) being provided at the periphery of an inertia piece (12A, 112A, 212A, 612A, 712A, 512A, 812A, 912A, 412A, 1012A), so that a lack of periodicity of the thermal engine of the motor vehicle is taken advantage of in order to make the complementary ramps make their relative circumferential movement in the direction of taking up of the play, wherein the friction clutch further comprises control means sensitive to a centrifugal force and to an angular acceleration and adapted to selectively control the operation of the play take-up device.