Hydraulic servo device for a friction brake in a planetary change-speed gearbox for motor vehicles

摘要

A stationary partition (25) between the sections (3,4) is situated after the piston (11) in the cylinder (2). The partition is sealed by a seal (36) and is fixed to a support plate (37). The piston rod (12) passes through the partition and is sealed by the seal. Another piston (27) is contained in the section (3) of the cylinder and is fixed to the piston rod and divides the section into an engaging pressure chamber (31) and a release pressure chamber (30). The engaging sides (15,31) of the two pistons in tandem formation and of the further piston are supplied by ducts (18,19) in the shared piston rod and by a duct (20) with transverse hole (33). The release pressure chambers are supplied by separate release ducts (24,32).