Hydraulically damped automatic play compensation device for motor vehicle clutches

Claim 1

Hydraulically damped automatic play compensating device for a motor vehicle clutch including: a clutch control lever which effects a working stroke upon the application of a clutch-disengaging force thereto; means for transmitting said force, and a fork operable by said control lever, through said means, wherein said play compensating device comprises, in combination: a lever attached at one end to said fork; means supporting said lever for pivotal movement about a pivot axis at said one end; a hydraulic damping cylinder acted upon by the other end of said lever and filled with hydraulic fluids; a shaft coaxial with said cylinder and slidable relative thereto, said shaft being connected by said force transmitting means to said control lever; a piston member attached to said shaft and subdividing said cylinder into two chambers, and flow restriction means interconnecting said two chambers, whereby, between working strokes, said cylinder is displaced relative to said shaft by an amount which compensates for wear in said clutch, the fluid pressure in said two chambers being equilibrated by flow through said restriction means, and the damping effect of said cylinder being such that, upon a subsequent working stroke, said force transmitting means transmits said force directly to said lever through said cylinder substantially without relative movement between said cylinder and said shaft.