Abstract: A temperature actuated switch having a resilient switch blade that is movable between open and closed positions and extends perpendicular to an elongated actuator of shape memory alloy. The actuator has an elongated deformed shape at normal temperatures and a contracted recovered shape at an elevated temperature. An end portion of the actuator is attached to the switch blade to provide movement of same between open and closed positions as the actuator changes between its deformed and recovered shapes.

Abstract: A humidity-modulated dual-setpoint temperature controller is disclosed in which the two setpoints of the temperature controller are adjusted as a function of measured humidity. Parameters other than humidity could also be used to adjust the dual setpoints of the temperature controller. The controller is particularly useful in controlling the heater element of a clothes dryer in order to improve the energy efficiency of the dryer.

Abstract: A high-sensitivity diode temperature sensor includes a reverse-biased diode, such as a Schottky diode, coupled to an adjustable constant current source for biasing the diode into a reverse operating region. The constant current source biases the diode at a particular reverse leakage current that corresponds to a temperature window over which the reverse voltage across the diode exhibits a linear response of several hundred mV/C. The change in reverse voltage can be used as a signal to switch power to an attached electrical load. Also disclosed is a dual-switchpoint temperature controller that incorporates the high-sensitivity diode temperature sensor with a feedback control circuit that enables the controller to switch power to a load at two adjustable setpoints using the single temperature sensor.