摘要 |
A truck (12′) for mounting a circuit breaker (13) in a switchgear frame (14′) includes wheels (16), a racking screw (20), a nut (22) threaded with the racking screw. The nut floats linearly with respect to the truck. A spring (23) is provided between a portion of the truck and the nut such that during movement of the truck into the frame, rotation of the racking screw causes linear movement of the nut, with the nut pushing against the spring, with the spring pushing the truck to move the truck linearly. Locking structure is coupled with the such that when the truck is stopped and the racking screw continues to rotate, the nut will move to compress the spring, causing the locking structure to move from an unlocked position, disengaged with the frame, to a locked position, engaged with the frame.
|