Sealed motor protector

Abstract

A motor overload protector or the like is disclosed in which a switch chamber is defined by a cup-shaped element and a header adhesively secured to the open mouth of the cup. A plurality of parallel support pins extend through and are adhered to the header to form a tight seal therewith. A flat continuous shoulder is provided within the housing which sharply intersects with the inner walls of the housing. One face of the header engages the shoulder and the edges of the header snugly engage a portion of the walls of the housing between the shoulder and the open mouth to form the switch chamber with the support pins extending into the chamber. A suitable plastic, such as epoxy resin, is provided in the space between the header and the open mouth to provide a tightly sealed switch chamber. A bimetal snap assembly is cantilever mounted by welding adjacent one of the support elements in the chamber and has a movable contact mounted on its free end. A fixed contact is welded to another one of the plurality of support pins so that the bimetal assembly operating in response to predetermined bimetal temperatures moves the movable contact into and out of contact with the fixed contact. In another embodiment of the invention, a resistance heater is associated with the bimetal snap element to increase current sensitivity.