×

Air-core choke coil

  • US 4,538,131 A
  • Filed: 11/30/1983
  • Issued: 08/27/1985
  • Est. Priority Date: 01/27/1983
  • Status: Expired due to Term
First Claim
Patent Images

1. An axially symmetric air-core choke coil, comprising:

  • at least one winding, said at least one winding having a plurality of helically wound, spaced apart, wire cable turns, said coil having an inner cylindrical periphery inside said coil and an outer periphery concentrically surrounding said inner periphery;

    a plurality of axially extending, electrically non-conductive, strips, spaced circumferentially around said at least one winding, each strip including a plurality of folded sections, respective ones of said folded sections being fitted between respective adjacent turns, a plurality of air gaps being defined between said turns and said strips, said strips being arranged to permit radial and longitudinal air flow through said air gaps;

    means for generating an axial air flow along said inner cylindrical periphery of said coil, said axial air flow being adapted to reduce the air pressure at said inner periphery to induce outside air to flow through said air gaps;

    said means for producing an axial air flow comprises a screen, said screen being adapted to block air flow through the center of one axial end of said coil and to define an axial gap between the circumferential periphery of said screen and said at least one winding of said coil, whereby air entering said axial gap is accelerated to produce said reduced air pressure along said inner periphery of said coil; and

    means for axially prestressing said at least one winding.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×