HYDRAULIC BRAKE BOOSTER AND VALVE MEMBER

摘要

HYDRAULIC BRAKE BOOSTER AND VALVE MEMBER A hydraulic brake booster includes a housing which defines a pressure chamber and a piston within the housing is movable in response to pressurized fluid within the pressure chamber to effectuate a brake application. The piston encloses a storage chamber and forms a passage communicating the storage chamber with the pressure chamber. A valve member is disposed within the passage to control communication between the storage chamber and the pressure chamber. An operator actuator cooperates with a control valve to communicate pressurized fluid to the pressure chamber and a finger is actuated by the operator actuator to engage the valve member, thereby opening communication between the storage chamber and the pressure chamber. The valve member comprises a unitary assembly having a sleeve sealingly engaging the wall of the piston passage, a seat member biased into engagement with a shoulder defined by a stepped bore on the sleeve, and a stem extending through a bore on the seat member.