Hydraulic change-over valve for a vehicle brake system

摘要

PCT No. PCT/EP93/00033 Sec. 371 Date Nov. 24, 1993 Sec. 102(e) Date Nov. 24, 1993 PCT Filed Jan. 9, 1993 PCT Pub. No. WO93/19960 PCT Pub. Date Oct. 14, 1993.A hydraulic change-over valve is adapted for a vehicle brake system with anti-lock control and traction slip control which operates according to the return delivery principle during an anti-lock control operation and the self-priming pump of which takes in pressure fluid through the master brake cylinder during a traction slip control operation. The change-over valve is arranged in the suction line between a pump and a master brake cylinder and shuts off the connection during each pedal-operated braking operation and opens it during each traction slip control operation. To avoid negative effects on the brake pedal feeling, restrictors are provided which prolong the closing time of the switch-over valve so that the fluid volume for switching is received gradually and continuously. The switching position is determined by a diaphragm, whose effective surface depends on its flexure to afford a non-stick-slip operation.