Double circuit main brake cylinder - has plunger to seal hydraulically interconnected treble chamber cylinder on circuit failure

摘要

Hydraulic pressure in the first chamber is generated by the direct action of the brake pedal through a linkage. The first and third chambers are connected by a small dia. pipe and a sealed fluid reservoir, the pressure in the first chamber thus generates pressure in the third chamber which operates one set of brakes. Pressure in the intermediate chamber is generated via a hydraulic coupling and operates the other set of brakes. In the event of loss of pressure in one of the brake pipes a spring loaded plunger in the piston seals the fluid supply hole, pressure continues to be supplied to the intake circuit via the action of the hydraulic connected between the pistons.