Electrode for plasma arc torch and method of making the same
AssigneeAmerican Torch Tip Company
InventorJeffrey K. Walters
Life of this patent
Estimating the term…
Abstract
An electrode for supporting an arc in a plasma arc torch. The electrode includes a metallic holder having a front end and a rear end. An emissive insert cavity is formed in the front end. An emissive insert is mounted in the cavity and is a metallic material having a relatively low work function. The front end is a casting made of a metal which is selected from silver, gold, platinum, rhodium, indium, palladium, nickel and alloys thereof. The rear end is a metal selected from copper and copper alloys. A cylindrical post extends inwardly from the front end of the metallic holder. The cylindrical post has an inner-rear tip portion which is a metal selected from copper and copper alloys.
Claims10
An electrode for supporting an arc in a plasma arc torch, the electrode comprising:
- a metallic holder including,
- a front end casting portion having an emissive insert cavity and an outer face, and
- a rear end portion joined to said front end casting portion;
- and
- an emissive insert mounted in said emissive insert cavity, said emissive insert being a metallic material having a relatively low work function,
- wherein said front end casting portion is a metal selected from silver, gold, platinum, rhodium, indium, palladium, nickel and alloys thereof, and
- wherein said rear end portion is a metal selected from copper and copper alloys.
A method of fabricating an electrode adapted for supporting an arc in a plasma arc torch, the electrode includes a holder having a front end portion and a rear end portion, the method comprising:
- machining a piece of material to form a rear end portion blank;
- forming a notch in one end of the rear end portion blank;
- disposing an end of an emissive insert into the notch;
- melting a metal selected from silver, gold, platinum, rhodium, indium, palladium, nickel and alloys thereof, and which is to be used to form the front end portion of the holder;
- casting the molten metal onto the emissive insert and onto an end of the rear end portion blank so as to form a front end portion blank, such that the front end portion blank and the rear end portion blank constitute a holder blank;
- and
- machining the holder blank to form a finished holder.
An electrode for supporting an arc in a plasma arc torch, the electrode comprising:
- a metallic holder including,
- a front end portion having an emissive insert cavity and an outer face, and
- a rear end portion joined to said front end portion;
- an emissive insert mounted in said emissive insert cavity, said emissive insert being a metallic material having a relatively low work function;
- and
- casting means for bonding together said front end portion, said rear end portion, and said emissive insert,
- wherein said front end portion is a metal selected from silver, gold, platinum, rhodium, indium, palladium, nickel and alloys thereof, and
- wherein said rear end portion is a metal selected from copper and copper alloys.
Dependencies are inferred from the claim text.