| 摘要 |
PCT No. PCT/GB97/01055 Sec. 371 Date Dec. 8, 1997 Sec. 102(e) Date Dec. 8, 1997 PCT Filed Apr. 17, 1997 PCT Pub. No. WO97/40300 PCT Pub. Date Oct. 30, 1997An actuation system particularly for the operation of a vehicle clutch and/or gearbox ratio selector members in which a pump charges an accumulator via a non-return valve. A slave cylinder receives pressurised fluid from the accumulator via a solenoid-operated control valve. The control valve also controls the exhaust of fluid from the slave cylinder. The control valve has a rest position in which pressurised fluid from the pump is returned to sump and the slave cylinder is vented to sump, a first energised position in which the return of pressured fluid to sump is cut-off and the slave cylinder remains vented to sump, and a further energised position in which venting of the slave cylinder is cut-off and the slave cylinder is supplied with pressurised fluid from the accumulator. The pump may be electrically driven and stopped when the accumulator pressure is above a pre-determined level. |
