Bistable electric switch with shape memory actuator



A bistable electric switch comprises as actuators a pair of opposing SMA wires (1, 2) acting on a drive element (6) integral with a snap-action spring (4) so as to toggle it between two stable positions corresponding to two operating positions of the switch, the drive element (6) being shorter than the distance existing between the two opposing SMA wires (1, 2) when one of the SMA wires is contracted and the other SMA wire is uncontracted. In this way, the entire force exerted by the activated SMA wire is used to overcome the resistance of the snap-action spring (4), therefore it is possible to use a stronger spring that provides a greater circuit closure force thus assuring a better electric contact and increasing the reliability of the switch.




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Patent Citations (4)

    Publication numberPublication dateAssigneeTitle
    CN-101465240-AJune 24, 2009毛秀娣;曾令斌Electrothermic steam control switch
    CN-201302965-YSeptember 02, 2009郑州宏大通信有限公司Hand-operated restoring open-circuit protector
    US-5990777-ANovember 23, 1999The Whitaker CorporationShape-memory wire actuated switch
    WO-0199135-A1December 27, 2001Tyco Electronics Amp GmbhCommutateur electrique bistable et relais comportant un tel commutateur

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    Publication numberPublication dateAssigneeTitle