| 摘要 |
A thermostatic switch including a bimetallic disc movable between two oppositely dished configurations with a snap action in response to changes in temperature, and a tapered, resilient contactless arm fixedly attached by an anchored end to the perimeter of the disc and having a movable end. The movable end of the arm is moved with the disc between two positions corresponding to the disc configurations. The arm has a relatively low mass and minimal influence on the thermal operating characteristics of the disc. The thermostatic switch also includes a conductive plate with the disc positioned adjacent to the plate and the arm being in direct electrical contact with the plate when in a first arm position for conducting low current therebetween and being out of electrical contact with the plate when in a second arm position. A projecting portion of the movable end of the arm penetrates and wipes any surface contaminants on the plate when moved to the first arm position and is held in tight engagement with the plate and the disc when in the two arm positions to decrease vibration sensitivity. The current provides base drive to a power transistor which provides a switched, relatively high-current conduction path to which a load may be connected. The arm carries no contacts and conducts only low current.
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