INDUCTOR FOR INTERNAL HEATING

• US 3,612,806 A
• Filed: 02/26/1970
• Issued: 10/12/1971
• Est. Priority Date: 02/26/1970
• Status: Expired due to Term

• Current Assignee: John C. Lewis, Wentworth Hamilton
• Original Assignee: John C. Lewis, Wentworth Hamilton
• Inventors: Lewis, John C., Hamilton, Wentworth
• Primary Examiner(s): Truhe, J. V.
• Assistant Examiner(s): Bender, L. H.
• Application Number:
  US05/014,544
• Time in Patent Office: 593 Days
• Field of Search: 219/10.79,10.49
• US Class Current: 219/644
• CPC Class Codes: H05B 6/101 for local heating of metal pieces

Abstract

An inductor for internal induction heating wherein the outer working surface only is made of a high electrically conductive material, and the remainder thereof defining a water-cooling passage is made of a less conductive material so that highfrequency electrical current must flow in the working surface which is closely adjacent to the surface to be heated. A conduit having one side made of copper and all other sides made of plastic is employed so that high-frequency electrical current is concentrated in the copper side which functions as the working surface.

Claims

1. In an inductor for inductively heating the inner cylindrical surface of an opening in a workpiece, said inductor comprising two leads adapted to be connected to a spaced high-frequency power source, and a single loop connected between said leads and having an outer surface with a diameter slightly less than the diameter of said inner cylindrical surface, said leads and said loop having internal coolant passageways, the improvement comprising, said loop formed from an electrical insulated annular channel terminating generally at said outer surface and an electrically conductive ribbon over said channel and forming said outer surface whereby said coolant passageway of said loop is formed by said channel and said ribbon.