ANTI-LOCK EQUIPPED VEHICLE BRAKE DEVICE

PURPOSE: To reduce costs by altering the structure of a transformer and composing an anti-lock device of a solenoid valve of simple structure in a brake system provided with anti-locking devices for rear wheel brakes and front wheel brakes, a rear wheel brake pressure transformer, and the like. CONSTITUTION: This device is provided with a brake pressure generator 3; anti-lock devices 8, 9 respectively for rear wheel brakes 4, 5 and front wheel brakes 6, 7; a rear wheel brake pressure transformer 10; a switching device 11; and a controller 12. The anti-lock device 8 is provided with an anti-lock valve device 16, a return pump 17 and a low pressure accumulator 18 common for the respective rear wheel brakes 4, 5. In this case, the anti-lock valve device 16 is composed of a brake pressure intesifying valve 21 and a brake pressure reducing valve 22 which are normally closed two-port position valves. The transformer 10 is provided with a two-port two-position valve 43, controllable by a step piston 31, between an inlet 40 and an outlet 25.