Control arrangement for a hydraulic brake system with an antiskid control device

Claim 1

A control arrangement for use in a hydraulic braking system, especially in a vehicular braking system equipped with an antiskid device, between a pressure source, at least one braking circuit leading to at least one wheel brake actuating cylinder, and a return conduit leading to a hydraulic fluid reservoir and including means for creating a pressure in said return conduit, comprising: a valve device including a housing defining a bore and a control piston received in said bore for movement axially thereof between a closing and opening position; means for biasing said control piston toward said closing position including a spring and means for transmitting the force of said spring to said control piston, including an auxiliary piston having an axial end surface facing away from said spring; means for causing pressurized hydraulic fluid from the pressure source to act of said end surface of said auxiliary piston upon brake pedal actuation to counteract the action of said spring on said auxiliary piston; means for urging said control piston toward said opening position, including means for supplying pressure prevailing in the return conduit to said control piston to act thereon in direction toward said opening position and further including means responsive to the opening of said control piston for admitting pressurized fluid from said pressure source to said braking circuit; wherein said return conduit includes a branch commencing at the wheel brake actuating cylinder and further comprising a control valve interposed in said branch; and further comprising a pressure-limiting valve interposed in said branch.