Thermostatically controlled heater

摘要

A thermostatically controlled heater for heating metal work pieces to within a selected temperature range prior to and during a welding process is disclosed. The heater comprises an electric heating element thermally connected to a heat conductive shoe and electrically connected to a source of electric power via a thermostat assembly. The thermostat assembly includes a heat conductive housing mounted on the heat conductive shoe in intimate thermal contact. The housing contains a thermostat having a thermal sensing area in thermal contact with an area of the heat conductive housing for regulating the amount of electricity conducted to the electric heating element. Accurate control of the temperature of the workpiece is accomplished by constructing the heat conductive housing so that the temperature gradient between the shoe and the thermostat matches the temperature gradient between the shoe and the workpiece itself.