Method of making a blow molded float switch assembly

Abstract

A float switch assembly for selectively energizing and deenergizing a fluid pump or other electronic equipment responsive to the rise and fall of a fluid level within a reservoir and a method of manufacturing or assembling the float switch assembly. The assembly includes a hollow tube having an open end wherein a mercury tilt switch is fixed. A plurality of conductors covered with a non-conductive material extend within the tube open end and are connected to the switch so that a current path may be provided between the conductors responsive to the angle of the switch. Ridges are provided on the outer surface of the tube near the open end and, a float bulb is provided substantially surrounding the tube below the ridges and sealingly connected upon the ridges. A potting epoxy compound surrounds the switch and the conductors within the tube so that electrical contact with a fluid through the open end is prevented. A cap is placed on the tube open end and is locked into place. During the method of manufacture, the float bulb is flow molded directly onto the hollow tube by surrounding the tube with a resilient heated plastic, crimping the float bulb plastic upon the tube ridges and forcing air through the tube open end and two holes on the tube wall so as to enlarge the float bulb plastic to a desired float bulb shape.