Abstract: A high voltage magnetic relay is enclosed by an insulating housing containing a gas such as sulfur hexafluoride under pressure. The switch terminals removably extend through a wall of the housing and are sealed. The magnet structure is removably connected to the housing by a sealed joint. A fill valve removably extends through a wall of the housing and is sealed thereto. The armature shifts a pivotal arm in the housing between open and closed contact positions.The housing is formed of a polyamide material having the property of being resistant to deterioriation by fluorine gas, said material being poly hexamethylene terephthalic amide.

Abstract: An interlock switch assembly is provided to prevent the application of electrical power to an X-ray unit when the access port or door is opened. The interlock switch includes two microswitches connected in series. The microswitches are actuated when the door is closed by a plunger mounted in the door which moves against a pair of spaced electrically conductive spring contact strips, and moves the strips against the actuator buttons of the microswitches. The plunger includes a pair of contact posts which establish electrical connection with the strips as the plunger is moved against the strips, and an electrical shunt is provided across the posts so that when the plunger contacts the strips, an electrical connection is provided from one strip to the other. The switch assembly provides electrical switching without arcing when the door is opened and closed under normal conditions.