US5101638A
Expired / Lapsed
US
⏱️ 0.0 years remaining
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 14:23
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.
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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) | 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 |