BOOSTER BRAKE WITH VARIABLE AMPLIFICATION FACTOR AND REDUCED HYSTERESIS (LAG) Russian patent published in 2002 - IPC

FIELD: automotive industry; boosted brakes. SUBSTANCE: device has master cylinder and pneumatic booster including rigid outer housing hermetically divided by movable partition into at least two chambers. Main hydraulic piston of master cylinder has hollow movable cylinder in which reactive piston can slide. Reactive piston has two-way normally open valve devices capable of interrupting communication between inner space of master cylinder and inner space of movable cylinder and containing first part pressed at rest to movable cylinder and second part pressed at rest to first part. It has also third piston installed for hermetically sliding in movable cylinder being pressed at rest to first part and provided with central hole ensuring communication between inner space of movable cylinder and inner space of master cylinder. Third piston is stepped and it can hermetically slide in stepped hole of movable cylinder. Diameter of front section of stepped hole is smaller than diameter of rear section of this hole. EFFECT: improved reliability, simplified design. 6 cl, 3 dwg