Explosively-actuated, multi-gap high voltage switch

An electrical switch for opening a first current path in which the switch is included, comprising:

• a terminal in the first path;
• a pair of normally electrically interconnected contacts which are separable along a first line of direction to both break the electrical interconnection and to form a first gap therebetween, the one contact being movable away from the other contact and toward the terminal as the contacts separate;
• first means for inserting a solid electrical insulator between the contacts as they separate to electrically insulate the first gap, said first means including a first electrically insulative member carried by and movable with the one contact so as to be interposed between the contacts as they separate, and an electrically insulative sleeve through which the one contact is movable and the first insulative member is conformally movable as the contacts separate;
• second means for electrically connecting one contact to the terminal when the contacts are interconnected, a second gap forming between the one contact and the terminal as the contacts separate at a predetermined time after the formation of the first gap;
• third means for inserting a solid electrical insulator between the one contact and the terminal as the contacts separate to electrically insulate the second galp, said third means including a second electrically insulative member carried by and movable with the one contact so as to be interposed between the one contact and the terminal as the contacts separate and a third electrically insulative member carried by the terminal so as to be interposed between the one contact and the terminal as the contacts separate, wherein the second and third insulative members conformally telescope as the contacts separate;
• fourth means for defining with the first means a chamber, pressurization of the chamber separating the contacts;
• ignitable means in the chamber, ignition of which pressurizes the chamber;
• a second current path;
• and
• fifth means for connecting the second path in shunt with the first path after the first gap is formed.

An electrical switch for opening a first current path in which the switch and a terminal are included, comprising:

• a second current path;
• first and second normally electrically interconnected contacts for carrying current in the first current path, the first contact being relatively movable along a fixed line of direction away from the second contact to break the electrical interconnection therebetween;
• first piston means on the first contact for
• (a) defining an enclosed chamber with the second contact when the contacts are interconnected;
• (b) interpositioning between the contacts to isolate the first contact from the chamber and electrically insulating the contacts from each other as and after the first contact moves away from the second contact, and wherein the first piston means forms an insulative first gap between the contacts as and after the first contact moves away from the second contact;
• (c) constricting any arc formed between the contacts after the first contact moves away from the second contact;
• second means for
• (a) electrically connecting the first contact to the terminal when the contacts are electrically interconnected, and
• (b) inserting a solid electrical insulator between the one contact and the terminal to electrically insulate the first contact from the terminal after the first contact moves away from the second contact, wherein the second means forms an insulated second gap between the first contact and the terminal at a predetermined time after the formation of the first gap;
• third means for electrically connecting the second path in shunt with the first path after the first gap is formed and before the second gap is formed;
• and
• ignitable means in the chamber for pressurizing the chamber upon ignition thereof to rapidly drive the first contact away from the second contact.

A high-voltage fuse having a high continuous current rating, comprising:

• a first current path having a high continuous current-carrying capacity;
• a second current path;
• a fuse in the second path;
• first means for opening a first insulated gap in the first path, an arc forming in the first gap;
• second means for connecting the second path in shunt with the first path as the voltage of the arc in the first gap elevates to transfer current from the first path to the second path;
• and
• third means for opening a second insulated gap in the first path after current therein transfers to the second path so that the second gap is uncontaminated and so that as the arc voltage of the fuse elevates, retransfer of the current to the first path is prevented by the presence of the first gap and the second uncontaminated gap in the first path.

The fuse of claim 20 or 16, wherein

• the first means comprises
• a pair of normally electrically interconnected contacts separable along a fixed line of direction to form the first gap,
• means for electrically insulating the first gap as the contacts separate, and
• ignitable means, ignition of which separates the contacts;
• and
• the third means comprises
• a terminal electrically connected to one contact when the contacts are interconnected, the second gap forming between the terminal and the one contact as the contacts separate, and
• means for electrically insulating the second gap as the contacts separate.