Patent ID: 8109087

Claim:
An overheating protection system adapted for use with an actuator including at least one shape memory alloy element coupled to, so as to selectively receive an activation signal from a source, wherein the actuator element presents a first configuration so as to be activated by the source over a first period, and is drivenly coupled to a load, said system comprising: at least one switching shape memory alloy element selectively coupled to the source and/or actuator element and presenting a second configuration, so as to be activated by the source and/or actuator element over a second period greater than the first, said actuator element, source and switching element being cooperatively configured such that the switching element is operable to prevent receipt of the signal by the actuator element, when the switching element is activated, wherein the actuator element presents a first transformation temperature range, and the switching element is thermally coupled to the actuator element, so as to be activated thereby, and presents a second transformation temperature range greater than the first, wherein the actuator and switching elements, and source compose a circuit, the source is operable to expose the actuator and switching elements to a current, so as to resistively generate a thermal activation signal, and the switching element is operable to open the circuit when activated, and wherein the switching element is drivenly coupled to an electrical isolator, and configured to cause the isolator to be intermediately positioned between the actuator and switching elements, when the switching element is activated.