Patent US2668122A successfully refreshed from Google Patents.
US4803452A
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US
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Superconductor for magnetic field shielding
Assignee: Koatsu Gas Kogyo Co Ltd
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Filing: 1987-12-29
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Granted: 1989-02-07
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Expires: 2007-12-29
Abstract
Abstract A magnetic field shield which is characterized in that it includes at least one composite lamination including a thin film of the superconductor and a metal layer laminated with the thin film of the superconductor having a thickness not more than that obtained at the turning point where the magnetic field shielding effect of a single film of the superconductor changes from an abrupt increase to a gradual increase and the film thickness is less than 2 μm.
Inventors
- 👤 Yoshiro Saji
- 👤 Eichi Tada
- 👤 Hiroaki Toda
- 👤 Yoshiaki Kawahara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:46
CPC Classifications
H; H05; H05K; H05K9/00; H05K9/0073; H05K9/0075; H05K9/0077; H10; H10N; H10N60/00; H10N60/20; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/9265; Y10S428/93
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
118 words
A magnetic field shield including a superconductor film having a magnetic field shielding effect which abruptly increases from the vicinity of the origin to a turning point of a graph illustrating the relationship between the thickness of a single layer of said superconductor film and the magnetic field shielding effect of said superconductor film, and after said turning point gradually increases as the thickness of said superconductor film increases, said magnetic field shield being characterized in that it comprises at least one composite lamination comprising a thin film of said superconductor, said thin film having a thickness not more than that obtained at said turning point and not less than 0.05 μm but not more than 2.0 μm.
Claim 2
Dependent Claim
118 words
A magnetic field shield including a superconductor film having a magnetic field shielding effect which abruptly increases from the vicinity of the origin to a turning point of a graph illustrating the relationship between the thickness of a single layer of said superconductor film and the magnetic field shielding effect of said superconductor film, and after said turning point gradually increases as the thickness of said superconductor film increases, said magnetic field shield being characterized in that it comprises at least one composite lamination comprising a thin film of said superconductor, said thin film having a thickness not more than that obtained at said turning point and not less than 0.05 μm but not more than 2.0 μm.
Claim 3
Dependent Claim
27 words
A magnetic field shield according to claim 1, wherein said superconductor film is a film formed on said metal layer by thin-film forming techniques such as sputtering.
Claim 4
Dependent Claim
22 words
A magnetic field shield according to claim 1, wherein said superconductor film is closely contacted with said metal layer by ultrasonic solder.
Claim 5
Dependent Claim
22 words
A magnetic field shield according to claim 1, wherein said superconductor film is simply laminated with said metal layer without adhering means.
Claim 6
Dependent Claim
27 words
A magnetic field shield according to claim 1, 2, 3 or 4, wherein said superconductor film is made of niobium, niodium alloys, niobium compounds or vanadium compounds.
Claim 7
Dependent Claim
24 words
A magnetic field shield according to claim 1, 2, 3 or 4, wherein said metal layer is a sheet made of aluminum or copper.
Claim 8
Dependent Claim
31 words
A magnetic field shield according to claim 1, 2, 3 or 4, wherein said metal layer is a thin aluminum film or a thin copper film made by thin-film forming techniques.
Claim 9
Dependent Claim
22 words
A magnetic field shield according to claim 1, 2, 3 or 4, further comprising a plurality of said composite laminations laminated together.
Claim 10
Dependent Claim
27 words
A magnetic field shield according to claim 5, wherein said metal layer is a thin aluminum film or a thin copper film made by thin-film forming techniques.
Claim 11
Dependent Claim
43 words
A magnetic field shield according to claim 1, 2, 3 or 4, further comprising at least another composite lamination comprising a thin film of said superconductor having a thickness not more than that obtained at said turning point laminated onto said composite lamination.
Claim 12
Dependent Claim
39 words
A magnetic field shield according to claim 5, further comprising at least another compsite lamination comprising a thin film of said superconductor having a thickness not more than that obtained at said turning point laminated onto said composite lamination.
Claim 13
Dependent Claim
39 words
A magnetic field shield according to claim 6, further comprising at least another composite lamination comprising a thin film of said superconductor having a thickness not more than that obtained at said turning point laminated onto said composite lamination.
Claim 14
Dependent Claim
39 words
A magnetic field shield according to claim 7, further comprising at least another composite lamination comprising a thin film of said superconductor having a thickness not more than that obtained at said turning point laminated onto said composite lamination.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-02-07 | 1992-08-08 | 1993-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-02-07 | 1996-08-08 | 1997-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-02-07 | 2000-08-08 | 2001-02-07 | $7700.00 | Window Closed / Lapsed |