Operating unit for hydraulic vehicle brake comprises casing which has bore with two sections of different diameter containing cylindrical piston and auxiliary piston with stepped cross-section

摘要

The operating unit for a hydraulic vehicle brake comprises a casing with a bore which has a large-diameter section (44) and a small-diameter section (46). A cylindrical piston (16) is mounted in the larger section and an auxiliary piston (48) with a stepped cross-section is mounted so that the larger section slides along the larger bore and the smaller section slides along the smaller bore. There is a pressure outlet (30) in the smaller bore and a second outlet (58) in the larger bore. This is connected to a control unit (62) which restricts the flow of fluid from it so that the auxiliary piston comes into sealing contact with the main piston.