PNEUMATIC BRAKE BOOSTER Russian patent published in 1998 - IPC

FIELD: automotive industry; automobile brake systems. SUBSTANCE: pneumatic brake booster has housing accommodating a piston consisting of hub and skirt forming front chamber which is in constant communication with vacuum source, and rear chamber selectively connected either with front chamber or with atmosphere through valve arrangement set into operation by control tie-rod. Booster has plunger, reactive disc reliably secured on axial tie-rod and control tie-rod return spring arranged between piston and plunger. Valve arrangement has shutter engaging with first circular seat of valve made on plunger and with second circular seat of valve made on piston. Shutter is provided with flexible diaphragm secured through its outer side edge to piston with provision of adequate tightness. EFFECT: improved reliability of operation. 11 cl, 2 dwg