Motor vehicle brake booster has constant pressure chamber and variable pressure chamber with vacuum valve seat on rear face of output piston

摘要

The motor vehicle brake booster has a casing defining a variable pressure chamber (6) and a constant pressure chamber (5) connected to an output piston (8). A vacuum valve seat is provided on the flat rear face of the output piston with a duct connected to the constant pressure chamber. The vacuum valve and an atmospheric pressure valve (33) seats are spaced axially for engagement for a valve member. There is a connecting passage between the valves and the variable pressure chamber.