An overspeed switching mechanism for a motor has an electrically conductive rotor driven by the motor, a movable drag mechanism having a permanent magnet structure linked magnetically with the rotor for movement of the mechanism through electromagnetic interaction between the magnet structure and the rotor, a latching mechanism linked with the drag mechanism by means of another permanent magnet structure for restraining movement of the drag mechanism until the rotor attains a preset speed at which the latching mechanism releases the drag mechanism and allows limited movement thereof, a switch, and an actuator operatively linked with the drag mechanism and the switch for translating movement of the drag mechanism into switching of the switch.
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