PRESSURE-OPERATED SWITCH FOR A CURRENT-LIMITING, HIGH- VOLTAGE INTERRUPTING MODULE

摘要

An improved switch in which a contact is moved away from a stationary contact by ignition of a power cartridge. The ignited power cartridge pressurizes a chamber defined by the stationary contact and an insulative trailer mounted to the movable contact to open the switch. The movable contact and its trailer move conformally through a bore of an insulative liner. The trailer and liner are made of ultra-high molecular weight polyethylene which is abrasion-resistant and has high surface lubricity - thereby ensuring free movement of the movable contact and the liner -- and which is non-brittle - thereby ensuring that forces applied to the trailer by the power cartridge do not shatter it. An inflexible disc of Lexan or Nylon may reside at the interface of the movable contact and the trailer to obviate extrusion of the trailer about the contact due to the forces applied to the trailer. If the switch is used to commutate current to a nearby fuse, the bore of the liner may be undercut to provide a volume into which the liner may expand when it is heated by operation of the fuse.