| 摘要 |
<p>In a brake by wire system, a linear differential pressure control valve (20.21,22,23) is provided to control accurately wheel cylinder pressure. A brake fluid conduit (51,61) extending from a reservoir (2) is branched out into two conduits (52,53,62,63), each of which is transmitted to each of right and left wheel cylinders (3,4,5,6). A linear differential pressure control valve (70,80) is disposed in the conduit and an another linear differential pressure control valve (20,21,22,23) in each of the branched out conduits. Brake fluid sucked from the reservoir by a motor pump (31,32,41,42) is discharged to each of the branched out conduits between the valve and the wheel cylinder. The two valves thus connected in series are operative step by step to control the wheel cylinder pressure in accordance with the current commanded in response to brake pedal depression. The former linear differential pressure control valve (70,80) is energized at first at a normal braking operation and, therefor, the identical pressure is applied to both of the wheel cylinders so that the detected wheel cylinder pressure may be adjusted. Further, a hybrid system using the brake by wire and a conventional master cylinder is also provided. <IMAGE></p> |
