Stepped bore type hydraulic booster - has master piston guided in bore of booster piston and subjected to reaction pressure

摘要

The hydraulic booster comprises a cylinder with bore of two different dias, the larger one accommodating a booster piston connected to one or more acutators, and the smaller one a master piston actuated by a pedal etc. The pressure-chamber, in which the pressure is formed thrusting the booster piston in the working direction, is connected either to the pressure supply or the return pipe via passages in both pistons and the housing, dependent on the relative position of the pistons to each other. The master piston is guided for part of its length in a bore in the booster piston. Its working face is always exposed to the pressure in the chamber formed by this bore and an annular chamber and which thrusts the booster piston in the working direction, so that this pressure can be felt as a reaction force opposing actuation of the master piston.