← Back to Patent Explorer
US4119825A Expired / Lapsed US ⏱️ 0.0 years remaining

Induction heating apparatus

Assignee: Rolls Royce PLC
•
Filing: 1975-11-17
•
Granted: 1978-10-10
•
Expires: 1995-11-17
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Induction heating apparatus for a dieless drawing operation includes a flexible induction coil made from a flexible metallic strip contained within an elastomeric sleeve which also defines a cooling fluid passage. The coil is sufficiently flexible to be capable of being formed into a shape which substantially conforms to that of a workpiece being heated at any point along the length of the workpiece. The apparatus of the invention also includes cam followers connected to the coil and cams which represent the shape of the workpiece over which the followers move during the heating operation to change the shape of the coil as required to maintain the coil at a substantially constant distance from the surface of the workpiece.

Inventors

  • 👤 Robert Graham Taylor
  • 👤 William Alfred Proops

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 00:41
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/02; H05B6/10; H05B6/101; H05B6/36; H05B6/42

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 173 words
Induction heating apparatus comprising a workholder adapted for supporting a workpiece; a flexible induction coil surround said workpiece in said workholder, said coil comprising a thin, flexible strip of an electrically conductive material and a flexible sleeve surrounding said strip and defining adjacent at least one surface of the strip a passage for the flow therethrough of a cooling medium; means for connecting the coil to a source of electrical energy; means for causing relative movement of the coil and workpiece along the length of the workpiece; cam means spaced from said workpiece, and cam follower means connected to said coil and engaging said cam means, said coil being of constant length adapted to contortion under the biasing of said cam means acting through said follower to encompass a variety of areas of different and irregular magnitude as said coil moves relative to the length of said workpiece whereby the coil may be maintained in a configuration corresponding substantially to that of the cross-section of the workpiece as the coil traverses the workpiece.
Claim 2
Dependent Claim 173 words
Induction heating apparatus comprising a workholder adapted for supporting a workpiece; a flexible induction coil surround said workpiece in said workholder, said coil comprising a thin, flexible strip of an electrically conductive material and a flexible sleeve surrounding said strip and defining adjacent at least one surface of the strip a passage for the flow therethrough of a cooling medium; means for connecting the coil to a source of electrical energy; means for causing relative movement of the coil and workpiece along the length of the workpiece; cam means spaced from said workpiece, and cam follower means connected to said coil and engaging said cam means, said coil being of constant length adapted to contortion under the biasing of said cam means acting through said follower to encompass a variety of areas of different and irregular magnitude as said coil moves relative to the length of said workpiece whereby the coil may be maintained in a configuration corresponding substantially to that of the cross-section of the workpiece as the coil traverses the workpiece.
Claim 3
Dependent Claim 55 words
Induction heating apparatus as claimed in claim 1 wherein said cam means are positioned along the length of the workpiece so that the radially inner surface of the coil may be positioned at a substantially constant distance from the surface of the workpiece while the workpiece is being heated at various locations along its length.
Claim 4
Dependent Claim 23 words
Induction heating apparatus as claimed in claim 1 the electrically conductive strip is a metallic strip and the sleeve is an elastomeric sleeve.
Claim 5
Dependent Claim 23 words
Induction heating apparatus as claimed in claim 1 the passage for the cooling medium is on the radially inner side of the coil.
Claim 6
Dependent Claim 52 words
Induction heating apparatus as claimed in claim 3, wherein the sleeve is made from a heat shrinkable fluorocarbon rubber which is shrunk over both the strip and a removable mandrel so that on removal of the mandrel there is formed the passage of the cooling medium and the strip is located therein.
Claim 7
Dependent Claim 123 words
Induction heating apparatus comprising a flexible induction coil adapted to surround a workpiece to be heated, said coil comprising a thin, flexible strip of an electrically conductive material and a flexible sleeve surrounding said strip and defining adjacent at least one surface of the strip a passage for the flow therethrough of a cooling medium, and means for connecting the coil to a source of electrical energy, said coil being of constant length adapted to contortion to encompass a variety of areas of different and irregular magnitude as said coil moves relative to the length of said workpiece whereby the coil may be maintained in a configuration corresponding substantially to that of the cross-section of the workpiece as the coil traverses the workpiece.
Claim 8
Dependent Claim 123 words
Induction heating apparatus comprising a flexible induction coil adapted to surround a workpiece to be heated, said coil comprising a thin, flexible strip of an electrically conductive material and a flexible sleeve surrounding said strip and defining adjacent at least one surface of the strip a passage for the flow therethrough of a cooling medium, and means for connecting the coil to a source of electrical energy, said coil being of constant length adapted to contortion to encompass a variety of areas of different and irregular magnitude as said coil moves relative to the length of said workpiece whereby the coil may be maintained in a configuration corresponding substantially to that of the cross-section of the workpiece as the coil traverses the workpiece.
Claim 9
Dependent Claim 24 words
Induction heating apparatus as claimed in claim 6, wherein the electrically conductive strip is a metallic strip and the sleeve is an elastomeric sleeve.
Claim 10
Dependent Claim 24 words
Induction heating apparatus as claimed in claim 6, wherein the passage for the cooling medium is on the radially inner side of the coil.
Claim 11
Dependent Claim 52 words
Induction heating apparatus as claimed in claim 6, wherein the sleeve is made from a heat shrinkable fluorocarbon rubber which is shrunk over both the strip and a removable mandrel so that on removal of the mandrel there is formed the passage for the cooling medium and the strip is located therein.

References Cited (Backward Citations)

US1493713A Cited
US2397442A Cited
US3281678A Cited
US3607138A Cited
US3525842A Cited
US3632943A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-10-09 1982-04-10 1982-10-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-10-09 1986-04-10 1986-10-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-10-09 1990-04-10 1990-10-10 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag