Sealed thermostat for use in defrost control systems

摘要

A sealed bimetal snap disc thermostat is disclosed which is suitable for use in environmental locations in which severe thermocycling occurs. The thermostat provides a disc cup having an imperforate end wall which is the only portion of the thermostat per se which is exposed. A non-metallic enclosure cup is formed with an aperture closely encircling the disc cup and which defines a cavity surrounding the remaining portions of the thermostat. A sealing compound, such as epoxy, fills such cavity. The disc cup is crimped onto the thermostat body and provides an extended portion which is spaced from the thermostat body so that the sealing adhesive provides an interface of substantial area with the metal disc cup to assure a continuing seal. Because the sealant and enclosure cup surround the entire thermostat except for the disc cup, the thermostat is thermally insulated from its environment except for the disc cup end face.