Abstract: A variable power control device for varying the operating duty cycle to an electrical load such as an electrical heating unit, for example, an electrical cooking range, heating pad and the like. The control device can be used to adjust the on time of the electrical load or the temperature of the electrical load. The control device includes a cycling cam which rotates at a constant velocity, and a rotatable movable adjustment cam. A cycling electrical contact switch is located with one contact thereof disposed to follow the contour of the cycling cam and the other contact thereof disposed to follow the contour of the adjustment cam. An on-off of electrical contact switch is associated with an on-off cam with one contact disposed to follow the contour of the on-off cam and the other contact being stationary.

Abstract: An improved heat sensing apparatus for an electric range automatic surface unit control in which the heat sensor housing is supported within the surface unit by an upwardly biased pivot arm. The upper portion of the sensing apparatus comprises a first utensil contacting layer of a low thermal mass, heat conductive material, a second layer of electrically insulative heat conductive material secured to the underside of the first contact layer, and a third layer of electrically conductive, heat conductive material secured to the underside of the second layer. A thermistor or thermocouple heat sensor is attached to the third layer to provide an electrical signal representative of the utensil temperature to the surface unit temperature controls.

Abstract: A disconnect switch or hot wire relay for use with a ground fault circuit interrupter in a power circuit to a load, such as an electric range, to provide ground fault protection for any circuit of the range. The switch has normally closed switch contacts, a biased actuator plunger for opening the contacts, a latching member for disabling the plunger, and an adjustable hot wire for releasing the latch and hence the plunger when the circuit is overloaded. The plunger of the switch is manually resettable from a remote position. The reset mechanism has an anti-tease or trip-free feature which prevents the operator from holding the disconnect contacts closed while a fault is present in the circuit.

Abstract: An adjustable time delay disconnect switch or hot wire relay for use with a ground fault circuit interrupter in a power circuit to a load, such as an electric range, to provide ground fault protection for any circuit of the range. The switch has normally closed switch contacts, a biased actuator plunger for opening the contacts, a biased latch for disabling the plunger, and an adjustable hot wire for releasing the latch and hence the plunger when the circuit is overloaded. The plunger is manually resettable when the circuit condition returns to normal.

Abstract: A differential expansion rod and tube thermostat wherein the material of the inner rod has a much lower coefficient of thermal expansion than does the material of the outer tube. The thermostat is adapted to be mounted through an opening in the wall of an oven cooking cavity. A certain amount of the tube remains outside the oven cooking cavity. The inner rod is adapted to lie within the oven cooking cavity. Joined to the inner rod is an extension strap of a material having a high linear coefficient of thermal expansion substantially the same as that of the outer tube. The longitudinal motion created by the difference in the rates of expansion between the outer tube and the combined inner rod and extension strap is transferred by a hinged amplifier lever to a switch mechanism which is calibrated to operate at a predetermined oven temperature.