| 摘要 |
<p>A force-applying system comprising a first direct electric actuator (1). and a second electrically-controlled spring-applied actuator (2) wherein the output force-applying member (15) of the second actuator is operable through a clutch (30,31) one clutch member (30) of which is operatively loaded by the force-applying spring (29) of the second actuator (2) and the other clutch member (31) of which is controlled by a solenoid (36) such that when the solenoid (36) is energised said other clutch member (31) is held out of engagement with said one clutch member (30) and when the solenoid (36) is de-energised the two clutch members (30,31) are engaged operatively to connect the spring (29) to the output member, the solenoid (36) and the electric motor (3) of the first actuator (1) being controlled through an electrical circuit which ensures that the electric motor (3) of the first actuator (1) is de-energised whilst the solenoid (36) is de-energised.</p> |
