US3953922A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of eliminating the training effect in superconducting coils by post-wind preload
Assignee: Energy Research and Development Administration ERDA
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Filing: 1975-02-24
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Granted: 1976-05-04
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Expires: 1995-02-24
Abstract
Abstract The training effect in superconducting coils is eliminated by winding the coil with a composite material that includes both a superconductor and a normal material and then applying stresses to the wound coil in the direction that electromagnetic stresses will be applied to the coil during normal use and in a magnitude greater than the calculated magnitude of the greatest electromagnetic stresses to be applied to the coil.
Inventors
- 👤 Joseph R. Heim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 10:08
CPC Classifications
H; H01; H01F; H01F6/00; H01F6/06; H01F41/00; H01F41/02; Y; Y10; Y10S; Y10S505/00; Y10S505/825; Y10S505/917; Y10S505/924; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/4902; Y10T29/49805
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
59 words
A method of conditioning a wound superconducting coil formed of a plurality of filaments of superconducting material in a matrix of normal conducting material comprising the step of: stressing the coil in the directions of the electromagnetic forces generated in normal use and in a magnitude greater than the magnitude of the maximum electromagnetic force generated in normal use.
Claim 2
Independent Claim
59 words
A method of conditioning a wound superconducting coil formed of a plurality of filaments of superconducting material in a matrix of normal conducting material comprising the step of: stressing the coil in the directions of the electromagnetic forces generated in normal use and in a magnitude greater than the magnitude of the maximum electromagnetic force generated in normal use.
Claim 3
Dependent Claim
47 words
The method of claim 1 wherein the step of stressing the coil comprises: inserting an expandable collet into the coil; expanding the expandable collet against the coil to strain the normal conducting material to a value of strain between 0.2% and 0.4%; and removing the expandable collet.
Claim 4
Dependent Claim
47 words
The method of claim 1 wherein the step of stressing the coil comprises: emplacing the coil in a coaxial annular cylinder; applying fluid pressure to the coaxial annular cylinder to compress the normal conducting material of the coil to a value of strain between 0.2% and 0.4%
Claim 5
Independent Claim
92 words
A method of preloading a wound superconducting solenoidal coil formed of a plurality of filaments of superconducting material in a matrix of normal conducting material comprising the steps of: placing a cylindrical mandrel coaxially within said coil, said cylindrical mandrel sized to make a close fit to said coil, said cylindrical mandrel of a material having a thermal coefficient of cubical expansion that is less than the thermal coefficient of cubical expansion of said normal conducting material; and cooling said coil containing said mandrel to cryogenic temperatures, whereby said coil is preloaded.
Claim 6
Independent Claim
92 words
A method of preloading a wound superconducting solenoidal coil formed of a plurality of filaments of superconducting material in a matrix of normal conducting material comprising the steps of: placing a cylindrical mandrel coaxially within said coil, said cylindrical mandrel sized to make a close fit to said coil, said cylindrical mandrel of a material having a thermal coefficient of cubical expansion that is less than the thermal coefficient of cubical expansion of said normal conducting material; and cooling said coil containing said mandrel to cryogenic temperatures, whereby said coil is preloaded.
Claim 7
Dependent Claim
12 words
The method of claim 4 wherein said mandrel is made of Invar.
Claim 8
Dependent Claim
22 words
The method of claim 5 wherein said step of cooling said coil comprises immersing said coil containing said mandrel in liquid nitrogen.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-05-04 | 1979-11-03 | 1980-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-05-04 | 1983-11-03 | 1984-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-05-04 | 1987-11-03 | 1988-05-04 | $7700.00 | Window Closed / Lapsed |