Wheel cylinder

摘要

A wheel cylinder includes a housing defining a bore. A piston is reciprocably received in the bore and cooperates with the housing to define a pressure chamber. The wheel cylinder comprises a passage for supplying pressurized fluid to the pressure chamber from a fluid pressure source. The supply passage includes a first portion defined by an annular groove on the piston and a blind axial bore in the piston which communicates with both the annular groove and with the pressure chamber. A valve apparatus is received in the blind bore and modulates the fluid pressure supplied to the pressure chamber as a function of the fluid pressure provided by the pressure source.