Hydraulic brake control valve - is operated by external plunger to vent fluid to reservoir

摘要

The valve has a floating piston (8) to modulate the brake pressure and a plunger (4) operated valve to vent the fluid pressure to a return line (3). The vent valve is arranged in such a way that it does not open when the brake inlet valve is open. The brake inlet valve is operated by a ball seal (17). In the venting position a cylindrical extension of the floating piston closes off the inlet to prevent loss of fluid from the supply line to the reservoir. The cyclic modulation control then uses a minimum of fluid so that braking efficiency is maintained.