| 摘要 |
A hydraulic actuation system for an automated transmission system having an active clutch which is engaged via a hydraulic clutch actuator 22 operated under pressure from the system. A main control valve 120 which selectively connects the clutch actuator 22 and gear engagement actuators 114, 115 to an accumulator 275 or to a reservoir 278 and an isolation valve 300 for isolating the gear engagement actuators from the main control valve 120 when the clutch actuator 22 is connected to the accumulator 275, thereby preventing leakage when the clutch is engaged. When the clutch actuator 22 is connected to the accumulator 275 the clutch is engaged and when connected to the reservoir 278 the clutch is disengaged. Two hydraulic systems may be connected in parallel (see fig 10) to control the clutcs (350, 360) of a twin clutch transmission system, allowing the system to be operated in a restricted emergency mode, using only one clutch. |
