| 摘要 |
A brake pressure control unit (1) for a motor vehicle hydraulic brake system in which the rear wheel brakes (3,4) are actuated by two separate brake circuits comprises two pressure-control valves (10,11) arranged coaxially in series in a housing, each valve being adapted to control the hydraulic connection between an hydraulic fluid source (2) and a respective rear wheel cylinder. The valves (10,11) are comprised by control pistons (12,16) which mutually engage and are arranged in series, one control piston (12) being subjectable to a control force (FST), and the other control piston (16) being hydraulically movable in the valve opening direction by the brake circuit pressure as controlled by the one control piston (12) and movable in the closing direction by the uncontrolled fluid source (2) pressure acting on the piston part (16a) The valve seats may alternatively be provided within the pistons 12,16. <IMAGE> |
