Brake system with slip control

Claim 1

A brake system with slip control for an automotive vehicle having front and rear vehicle wheels with wheel brakes, said system comprising, in combination: a pedal-actuating vacuum booster (3); a dual-circuit master cylinder (2) operatively connected to said booster (3) and said master cylinder (2) having first and second working chambers (8, 9) therein; an auxiliary-pressure source (62) having a pump (26) whose input is connected to a pressure-fluid supply reservoir (20); a plurality of wheel sensors (S1-S4) coupled to said wheels for generating electric signals indicative of wheel rotational behavior; an electronic circuit (44) respective of said electric signals for providing braking-pressure control signals; pressure fluid lines respectively coupled between said auxiliary-pressure source (62), said reservoir (20), said first and second chambers (8, 9) and said wheel brakes; first, second and third normally closed outlet valves (30, 35, 36) respectively connected in the pressure fluid lines between said reservoir (20) and a first one of said front wheels, a second one of said front wheels and a joint connection of said rear wheels; first and second normally open inlet valves (27, 28) respectively connected in the pressure fluid lines between said first and second chambers (8, 9) and selected ones of said wheel brakes; a third normally open inlet valve (29) connected between said auxiliary-pressure source (62) and said joint connection of said rear wheels; first and second normally closed inlet valves (38, 39) respectively connected between said auxiliary-pressure source (62) and said first and second ones of said front wheels; and, wherein said first and second normally closed inlet valves (38, 39) open during anti-skid control.