US4639672A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Nuclear magnetic resonance apparatus
Assignee: US Philips Corp
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Filing: 1984-10-10
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Granted: 1987-01-27
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Expires: 2004-10-10
Abstract
Abstract Inside the gradient coils in the magnet system of a nuclear magnetic resonance apparatus there is arranged a sleeve which forms a noise-absorbing shield between the gradient coils and the measurement space. The shield is preferably formed by an evacuated space between the sleeve and a support for the gradient coils. This space is then provided with elastic vacuum seals at its axial ends.
Inventors
- 👤 Chritien J. M. Beaumont
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:29
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/28; G01R33/38; G01R33/385; G01R33/3854; Y; Y10; Y10S; Y10S505/00; Y10S505/825; Y10S505/842; Y10S505/843; Y10S505/844
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
74 words
A nuclear magnetic resonance apparatus comprising an electromagnetic main coil system extending about a generally cylindrical interior area and generating a homogeneous magnetic field in a measuring space within said interior area, a gradient coil system for generating gradient fields in said measurement space, and noise absorbing means disposed between said measurement space and said gradient coil system for reducing, within said measurement space, noise produced by said gradient coil system upon activation thereof.
Claim 2
Dependent Claim
74 words
A nuclear magnetic resonance apparatus comprising an electromagnetic main coil system extending about a generally cylindrical interior area and generating a homogeneous magnetic field in a measuring space within said interior area, a gradient coil system for generating gradient fields in said measurement space, and noise absorbing means disposed between said measurement space and said gradient coil system for reducing, within said measurement space, noise produced by said gradient coil system upon activation thereof.
Claim 3
Dependent Claim
43 words
The apparatus according to claim 1 wherein said noise absorbing means includes a sleeve which is generally coaxial with said interior region and is arranged between said gradient coil system and said measurement space so as to form a noise absorbing shield therebetween.
Claim 4
Dependent Claim
57 words
The apparatus according to claim 2 including a second cylindrical sleeve disposed about and coaxial with said first-named sleeve and means disposed at each end of said sleeves for sealing the space therebetween so as to form a sealed space which can be evacuated, said sealed space extending between said measuring space and said gradient coil system.
Claim 5
Dependent Claim
18 words
The apparatus according to claim 3 wherein said second sleeve forms a support for said gradient coil system.
Claim 6
Dependent Claim
26 words
The apparatus according to claim 3 or 4, wherein said sealing means includes an inflatable hollow elastic ring disposed between said sleeves at each end thereof.
Claim 7
Dependent Claim
19 words
The apparatus according to claim 2 wherein said sleeve is made of plastic having a comparatively low thermal conductivity.
Claim 8
Dependent Claim
15 words
The apparatus according to claim 2 wherein said sleeve is made of noise absorbing material.
Claim 9
Dependent Claim
19 words
The apparatus according to claim 2 wherein said surface of said sleeve is provided with a thermal radiation shield.
Claim 10
Dependent Claim
29 words
The apparatus according to claim 2 wherein said sleeve acts as a support for parts of the apparatus which are to be arranged in or near said measuring space.
References Cited (Backward Citations)
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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) | 1990-01-26 | 1990-07-28 | 1991-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-26 | 1994-07-28 | 1995-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-26 | 1998-07-28 | 1999-01-27 | $7700.00 | Window Closed / Lapsed |