| 摘要 |
<p>A clutch control system comprises a spool valve having an inlet port (14), a service port (16) and an outlet port (18). A spool (20) comprises a first land (24) and a second land (26) and is movable to open and close the ports (14, 16, 18). The spool is biased towards the inlet port (14) by a spring (30) and can be moved in the opposite direction by a solenoid (36) (not shown). If the solenoid is inoperative due to a failure, the outlet port (18) is connected to the service port (16) by a passage (34) such that the clutch can gently engage.</p> |
