Pressure control for dual-circuit brake system - has pressure limiting valve in one circuit by=passed if pressure in other fails

摘要

The brake pressure control is intended for a hydraulic brake system in a vehicle having separate circuits for the rear wheels. The first circuit has a pressure reducing valve arranged in a stepped piston with the source pressure acting on the smaller area and the brake cylinder pressure on the larger area against the operating force. The second circuit has a pressure limiting valve in a slave piston with the two brake cylinder pressures acting on both ends. An annular piston, slidable on the piston near the inlet, allows connection from inlet to outlet only via the limiting valve, with the outlet pressures equal. If the first circuit outlet pressure fails, it moves to provide direct passage from the inlet to the outlet.