Device for operating clutch of vehicle

A clutch operating device for use in vehicles for pushing the clutch disengaging members of a dry disk clutch which is disposed between a flywheel mounted on the output shaft of an engine and a propeller shaft rotatably supported by a support wall of a transmission case, the device being characterized in that the device comprises:

• an annular cylinder chamber provided on the support wall concentrically with the propeller shaft;
• an annular piston axially slidably fitted in the cylinder chamber;
• a release bearing mounted on the forward end of the piston and engageable with the clutch disengaging members by contact therewith;
• and
• means for supplying an oil pressure to the cylinder chamber by depressing a clutch pedal to push out the piston toward the clutch disengaging members;
• said cylinder chamber includes an annular space formed between a tubular portion surrounding the propeller shaft and projecting from the support wall toward the clutch and a hollow cylinder provided around the tubular portion, said hollow cylinder is formed with an oil pressure relief port communicating with the cylinder chamber only when the piston has reached a position immediately before a projection limit.