Abstract: A thermally responsive switching device suitable for use as a motor protector and the like is disclosed. Such device includes a housing assembly consisting of a thermoplastic base and a shallow drawn metallic cover. The base provides sidewalls extending to a peripheral flange against which a flange on the cover is positioned. The thermoplastic material is deformed inwardly around the cover flange to permanently connect the assembly. The switch includes an elongated bimetal snap element supported at one end on the end of a heater in heat exchange relation therewith. The other end of the heater is connected to an external terminal through an opening in the thermoplastic base. The terminal provides a tubular projection extending through the opening and a plurality of inwardly extending, resilient tabs which are welded to the heater.

Abstract: A probe thermostat is disclosed having a positive-off element included in the switch portion of the thermostat which prevents the switch from being closed when the variable control means of the thermostat is set to its extreme or "off" position. The positive-off element assures that the switch will be open even if a mulfunction occurs in the thermostat which would otherwise result in closing of the switch and undesirable current flow to the heating element. The illustrated form of positive-off element comprises an insulative threaded fastener attached to a portion of the base of the thermostat which engages one of the contact arms to hold it away from the other contact arm when the variable control means is set to its extreme "off" position.