Abstract: A fail safe temperature control device which consists of a nonelastic container or bulb adapted to be subjected to temperature changes, a capillary tube and a pressure responsive device. The container generally is located in the area in which the heat is to be controlled, typically an oven or other heated area. The capillary tube is connected to the container at a first end and to the pressure responsive device at a second end. The nonelastic container, capillary tube and pressure responsive device form a closed system which is filled with a thermally responsive material. The pressure responsive device operates a control device, typically consisting of a normally closed contact and a normally open contact.

Abstract: A fail safe device for use in conjunction with a temperature sensing bulb, capillary, and control device in an oven or other heating appliance, which fail safe device will prevent a failure of the basic control device from permitting a critical overheat condition to occur in the controlled area.

Abstract: This invention relates generally to apparatus wherein a change in temperature is transmitted from a sensing bulb through a capillary to a control device. More particularly this invention is related to a novel, fail safe device for use in conjunction with a temperature sensing bulb, capillary, and control device in an oven or other heating appliance.

Abstract: This invention relates generally to thermal control apparatus wherein a change in temperature is transmitted from a sensing bulb through a capillary to a control device. More particularly this invention is related to a novel, fail-safe control device for use in conjunction with a temperature sensing bulb, capillary, and control device in an oven or other heating facility whereby a loss of pressure within the bulb, capillary, control device system will cause the heating device to be shut off and thus will prevent the oven or other heating facility from being overheated.

Abstract: A temperature responsive control device is provided for controlling an electric oven. The device is comprised of a housing which contains an electrical switching means which is controlled by a temperature sensitive expansible member through a snap-acting spring mechanism. The expansible member consists of a hydraulic diaphragm, a fluid filled capillary tube and a temperature-sensing bulb. The hydraulic diaphragm is composed of two generally circularly shaped plates which are welded together at their edges. The top of the diaphragm contains a circular stud the top of which is conically shaped and is received into a conical bearing recessed into the shaft of a rotatable temperature setting means. One corner of the diaphragm is formed to fit into a notch in the interior of the housing. One end of the capillary tube is inserted directly into a small inwardly extending channel in the edge of the diaphragm and the other end contains the temperature-sensing bulb.