Pneumatic booster with reduced load and reduced hysteresis

摘要

PCT No. PCT/FR95/01089 Sec. 371 Date Sep. 19, 1995 Sec. 102(e) Date Sep. 19, 1995 PCT Filed Aug. 17, 1995 PCT Pub. No. WO96/07573 PCT Pub. Date Mar. 14, 1996A pneumatic-controlled device for a vacuum brake booster having a hollow piston which retains a tubular shut-off member. The tubular shut-off member interacts with a stationary seat and a movable seat to define a chamber within the hollow piston when the movable seat is in an actuation position. An orifice formed in the tubular shut-off member places the chamber in communication with a passage defined between the stationary and movable seats to reduce hysteresis experienced by movement of the movable seat.