Pulsator-operated valving with reaction chamber accumulator for

Abstract

A fluid pressure booster device includes a booster body, a control piston in the booster body for forward and rearward movements to define a boosting chamber between the control piston and a rear surface of a master piston of a master cylinder, a valve piston in the control piston for forward and rearward movements and communicating at its front face with the boosting chamber, a reaction piston in the control piston for forward and rearward movements and connected to an operating member, the reaction piston defining a reaction chamber between itself and a rear face of the valve piston, a stroke accumulator having an accumulation chamber connected to the reaction chamber, an inlet valve disposed between the control piston and the valve piston and interposed in a flow passage extending between the boosting chamber and a fluid pressure source, the inlet valve being closed when the valve piston is retracted and opening when the valve piston advances, and an outlet valve disposed between the control piston and the valve piston so as to open when the valve piston is retracted and to be closed when the valve piston advances. This enables a fluid pressure to be applied to the master cylinder in response to the motion of the operating member within a restricted stroke range.