Patent US5101638A successfully refreshed from Google Patents.
US5101638A
Expired / Lapsed
US
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Magnetic field generating system
Assignee: Oxford Instruments Superconductivity Ltd
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Filing: 1990-09-10
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Granted: 1992-04-07
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Expires: 2010-09-10
Abstract
Abstract A magnetic field generating system comprises a magnetic field generator (1); and a cooling system (4) having at least one thermal shield (6) surrounding the magnetic field generator. The system further comprises a temperature monitor (14, 15) for monitoring the thermal shield temperature; and heating means (13) for selectively heating the thermal shield so as substantially to maintain the monitored temperature substantially constant.
Inventors
- 👤 Keith White
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:22
CPC Classifications
H; H01; H01F; H01F6/00; H01F6/04; F; F17; F17C; F17C13/00; F17C13/02; F17C13/026; F17C3/00; F17C3/02; F17C3/08; F17C3/085; G; G01; G01R; G01R33/00; G01R33/20; G01R33/28; G01R33/38; G01R33/381; G01R33/3815; F17C2201/00; F17C2201/03; F17C2201/032; F17C2250/00; F17C2250/03; F17C2250/032; F17C2250/04; F17C2250/0404; F17C2250/0439; F17C2250/06; F17C2250/0605; F17C2250/0631; Y; Y10; Y10S; Y10S505/00; Y10S505/825; Y10S505/888; Y10S505/892
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
83 words
A magnetic field generating system, comprising: a magnetic field generator; a cooling system having at least one thermal shield surrounding said magnetic field generator; heating means for selectively heating said thermal shield; and control means for selectively heating said thermal shield; and control means for selectively activating said heating means during operation of the magnetic field generating system so as substantially to maintain the thermal shield temperature at a reference temperature and thereby maintain the electrical conductivity of said thermal shield substantially constant.
Claim 2
Dependent Claim
83 words
A magnetic field generating system, comprising: a magnetic field generator; a cooling system having at least one thermal shield surrounding said magnetic field generator; heating means for selectively heating said thermal shield; and control means for selectively heating said thermal shield; and control means for selectively activating said heating means during operation of the magnetic field generating system so as substantially to maintain the thermal shield temperature at a reference temperature and thereby maintain the electrical conductivity of said thermal shield substantially constant.
Claim 3
Dependent Claim
17 words
A system according to claim 1, further comprising: a temperature monitor for monitoring said thermal shield temperature.
Claim 4
Dependent Claim
56 words
A system according to claim 2, wherein said temperature monitor includes: a temperature detector for sensing the temperature of said thermal shield; and comparison means for comparing said detected temperature with said reference temperature; and wherein said control means selectively activates said heating means so as to maintain said detected temperature at substantially said reference temperature.
Claim 5
Dependent Claim
18 words
A system according to claim 3, wherein: said comparison means and control means include a suitably programmed microprocessor.
Claim 6
Dependent Claim
15 words
A system according to claim 1, wherein: heating means is mounted on said thermal shield.
Claim 7
Dependent Claim
30 words
A system according to claim 1, wherein said magnetic field generator includes: a main field generator; and gradient magnetic field generating means for generating at least one gradient magnetic field.
Claim 8
Dependent Claim
29 words
A system according to claim 6, wherein said control means includes: means for selectively activating said heating means during a pulse operation of said gradient magnetic field generating means.
Claim 9
Dependent Claim
37 words
A system according to claim 1, further comprising: a cryostat surrounding at least a portion of said magnetic field generator so as to cause said portion to be superconducting, and wherein said cryostat includes said thermal shield.
Claim 10
Independent Claim
81 words
A method of operating a magnetic field generating system comprising a magnetic field generator, a cooling system having at least one thermal shield surrounding the magnetic field generator, and heating means for selectively heating the thermal shield, the method comprising the step of: selectively energizing said heating means during operation of the magnetic field generating system so as substantially to maintain said thermal shield temperature at a reference temperature and thereby maintain the electrical conductivity of said thermal shield substantially constant.
Claim 11
Independent Claim
81 words
A method of operating a magnetic field generating system comprising a magnetic field generator, a cooling system having at least one thermal shield surrounding the magnetic field generator, and heating means for selectively heating the thermal shield, the method comprising the step of: selectively energizing said heating means during operation of the magnetic field generating system so as substantially to maintain said thermal shield temperature at a reference temperature and thereby maintain the electrical conductivity of said thermal shield substantially constant.
Claim 12
Dependent Claim
31 words
A method according to claim 9, further comprising the step of: monitoring the thermal shield temperature and selectively energizing said heating means when the monitored temperature differs from the reference temperature.
Claim 13
Dependent Claim
22 words
A method according to claim 9, further comprising the step of: generating a gradient magnetic field with gradient magnetic field generating means.
Claim 14
Dependent Claim
46 words
A method according to claim 11, wherein said step of selectively energizing said heating means includes the steps of: energizing said heating means when said gradient magnetic field generating means is de-energized; and de-energizing said heating means when said gradient magnetic field generating means is energized.
Claim 15
Independent Claim
122 words
An apparatus having a magnetic field generating system for performing a nuclear magnetic resonance experiment, comprising: a magnetic field generator having a main field generator and a gradient field generating means for generating a gradient magnetic field; a cooler having a thermal shield surrounding said magnetic field generator; heating means for selectively heating said thermal shield; and control means for selectively activating said heating means during operation of the magnetic field generating system so as to substantially maintain the temperature of said thermal shield at a reference temperature and thereby maintain the electrical conductivity of said thermal shield substantially constant, said control means including means for selectively activating said heating means during a pulse operation of said gradient magnetic field operating means.
Claim 16
Independent Claim
122 words
An apparatus having a magnetic field generating system for performing a nuclear magnetic resonance experiment, comprising: a magnetic field generator having a main field generator and a gradient field generating means for generating a gradient magnetic field; a cooler having a thermal shield surrounding said magnetic field generator; heating means for selectively heating said thermal shield; and control means for selectively activating said heating means during operation of the magnetic field generating system so as to substantially maintain the temperature of said thermal shield at a reference temperature and thereby maintain the electrical conductivity of said thermal shield substantially constant, said control means including means for selectively activating said heating means during a pulse operation of said gradient magnetic field operating means.
Claim 17
Independent Claim
103 words
A method of operating an apparatus for performing a nuclear magnetic resonance experiment, the apparatus having a magnetic field generating system comprising a magnetic field generator having a gradient magnetic field generating means for generating a gradient magnetic field, a cooler having a thermal shield surrounding the magnetic field generator, and heating means for selectively heating the thermal shield, comprising the step of: selectively energizing the heating means during operation of the magnetic field generating system so as to substantially maintain the temperature of the thermal shield at a reference temperature and thereby maintain the electrical conductivity of the thermal shield substantially constant.
Claim 18
Independent Claim
103 words
A method of operating an apparatus for performing a nuclear magnetic resonance experiment, the apparatus having a magnetic field generating system comprising a magnetic field generator having a gradient magnetic field generating means for generating a gradient magnetic field, a cooler having a thermal shield surrounding the magnetic field generator, and heating means for selectively heating the thermal shield, comprising the step of: selectively energizing the heating means during operation of the magnetic field generating system so as to substantially maintain the temperature of the thermal shield at a reference temperature and thereby maintain the electrical conductivity of the thermal shield substantially constant.
References Cited (Backward Citations)
US4448042A
Cited
US4535595A
Cited
US4655045A
Cited
US4689970A
Cited
US4660013A
Cited
US4817706A
Cited
US4777807A
Cited
US4788834A
Cited
JPS6449407A
Cited
US4782671A
Cited
US4884409A
Cited
US4990878A
Cited
US4986078A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-04-07 | 1995-10-07 | 1996-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-04-07 | 1999-10-07 | 2000-04-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-04-07 | 2003-10-07 | 2004-04-07 | $7700.00 | Window Closed / Lapsed |