摘要 |
A force-applying system is provided which combines a first direct electric actuator and a second, electrically controlled spring-applied actuator. The output force-applying member of the second actuator is operable through a force-transfer device one member of which is operatively loaded by the force-applying spring of the second actuator and another member of which is controlled by a solenoid. The operation is such that when the solenoid is energized, the members are out of engagement and when the solenoid is de-energized, the two members are engaged so as to operatively connect the spring to the output member. The solenoid and the electric motor of the direct actuator are controlled through an electrical circuit which ensures that the electric motor of the direct actuator is de-energized when the solenoid is de-energized. |