Abstract: A bistable shape memory alloy (SMA) micro-switch includes a single continuous SMA element such as a nitinol wire that provides bi-directional motion for switching functions. Bifunctional contact arms provide a mechanical force to maintain an open state of the micro-switch in addition to conducting current through a circuit. The SMA element includes first and second segments that are alternately heated above a transition temperature to cause the SMA element to alternate between first and second conformations. A cursor attached to the SMA element moves from a first position to a second position as the SMA element moves from its first to its second conformation. To close the SMA micro-switch, the contact arm is moved from an open position to a closed position through sliding contact with the cursor as the cursor moves from its second position to its first position.

Abstract: The present invention provides a bistable switch using a shape memory alloy, and a method for manufacturing the same. More specifically, the bistable switch includes a substrate having at least one power source; a flexible sheet having a first distal end attached to the substrate; a bridge contact formed at a second and opposite distal end of the flexible sheet; and at least one heat activated element connected to a first surface of the flexible sheet and between the second distal end and the power source. During operation, current from the power source passing through the heat activated element to indirectly bend the flexible sheet and short the signal contacts on the substrate with a sustainable force.