| 摘要 |
Secured by rivets to a rigid support is a bimetal resilient strip with a heater winding around it, in series with the power supply to the motor. The circuit is also closed by a moving contact and a fixed contact. The moving contact is mounted at the free end of a leaf spring clamped at the other end to the rigid support. The leaf spring is shaped as a rectangular frame with a blade projecting from its fixed end into its central rectangular opening, so that it can be bent upwards or downwards out of the plane of the frame. When the two contacts are closed the frame is horizontal and its blade is bent downwards attached to an auxiliary U-shaped spring. When the contacts are open, the auxiliary spring can tilt, allowing the blade to swing upwards and the frame bend downwards until its free end rests on a strip surface below. The blade has a rectangular free end with projecting lugs between which the T shaped upwardly bent free end of the bimetal strip is locked.
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