Double pole-double throw proximity switch

摘要

Proximity switches include a hermetically sealed unit that can be used in harsh environments and under significant pressures, such as underwater and in nuclear power facilities, without having any parts that would require replacement or periodic maintenance. The proximity switches are preferably switches actuated by physical movement of a contact in response to changing magnetic forces. The switches are preferably disposed in a body tube optionally including a hermetic seal assembly to seal an open end of the body tube and/or a ferrule that prevents electrical wires attached to the switch inside the body tube from being pulled away from the switch. Further, the switches preferably maintain a contact pressure between electrical contacts sufficient to withstand acceleration seismic testing of 10 g with no contact discontinuity.

主权项

1. A proximity switch comprising:
a body tube having bore with an open end; a switch assembly disposed inside the bore; a plug having a body that fits inside the open end and locks against an annular wall of the bore, the plug body having a second bore; an electrical lead electrically coupled with the switch assembly and extending through the second bore; a ferrule surrounding the electrical lead and disposed inside the second bore; and a jam nut coupled with the plug and urging the ferrule into sealing contact with the second bore and locking the electrical lead in a fixed position within the second bore.