Patent DE562934C successfully refreshed from Google Patents.
Patent US4681729A successfully refreshed from Google Patents.
US4681729A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Monitoring temperature within a vessel
Assignee: National Nuclear Corp Ltd
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Filing: 1985-05-06
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Granted: 1987-07-21
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Expires: 2005-05-06
Abstract
Abstract A vessel for the storage and monitoring of nuclear fuel materials incorporates a device (12) within its interior for providing an externally detectable signal indicating whether any temperature rise has occurred. The device (12) comprises a magnet (32) attracted towards a boundary wall (11) of the vessel and maintained in that position by a temperature-sensitive element such as a thermal link (38). The magnet (32) is subjected to an oppositely directed force by a spring (30), which is effective to drive the magnet (32) away from the wall (11) in the event of a substantial temperature rise within the vessel thereby producing an externally detectable change in magnetic flux.
Inventors
- 👤 Eric Pendleton
- 👤 Karl A. Roberts
- 👤 Alan Murray
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:46
CPC Classifications
G; G21; G21C; G21C17/00; G01; G01K; G01K3/00; G08; G08B; G08B21/00; G08B21/18; G08B21/182; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
129 words
A vessel provided internally with a device for enabling external detection of temperature changes within the vessel, said device comprising a permanent magnet, means mounting the magnet within the vessel for movement towards and away from a boundary wall of the vessel, means having sufficient magnetic coupling with the magnet to restrain the magnet against movement away from a predetermined position with espect to said boundary wall of the vessel, and temperature-responsive means for urging the magnet away from said predetermined position such that, in the event of a substantial rise in temperature within the vessel, the latter means becomes effective to move the magnet relative to the boundary wall to vary the magnetic field strength detectable by detector means located on the external side of said boundary wall.
Claim 2
Dependent Claim
129 words
A vessel provided internally with a device for enabling external detection of temperature changes within the vessel, said device comprising a permanent magnet, means mounting the magnet within the vessel for movement towards and away from a boundary wall of the vessel, means having sufficient magnetic coupling with the magnet to restrain the magnet against movement away from a predetermined position with espect to said boundary wall of the vessel, and temperature-responsive means for urging the magnet away from said predetermined position such that, in the event of a substantial rise in temperature within the vessel, the latter means becomes effective to move the magnet relative to the boundary wall to vary the magnetic field strength detectable by detector means located on the external side of said boundary wall.
Claim 3
Dependent Claim
53 words
A vessel as claimed in claim 1 in which said vessel boundary wall is composed of a magnetically soft material and constitutes said restraining means, and in which the urging means develops sufficient power to move the magnet away from said boundary wall in the event of a substantial rise in internal temperature.
Claim 4
Dependent Claim
61 words
A vessel as claimed in claim 1 in which a magnetically soft element determines said predetermined position, said element being fixed against movement with respect to said boundary wall and constituting said restraining means, and in which the urging means develops sufficient power to move the magnet away from said element in the event of a substantial rise in internal temperature.
Claim 5
Dependent Claim
55 words
A vessel as claimed in claim 1 in which said urging means includes a thermal link which, while intact, restrains the urging means from exerting its urging force on the magnet but breaks in response to substantial temperature rise and thereby renders the uring means effective to move the magnet away from said predetermined position.
Claim 6
Dependent Claim
16 words
A vessel as claimed in claim 1 in which said urging means includes a bimetallic component.
Claim 7
Dependent Claim
22 words
A vessel as claimed in claim 1 in which said boundary wall is constituted by a top wall portion of the vessel.
Claim 8
Dependent Claim
46 words
A handling and monitoring facility for spent nuclear fuel material comprising at least one vessel as claimed in claim 1, and detector means external to the vessel and responsive to changes in magnetic flux caused by movement of said permanent magnet away from said predetermined position.
Claim 9
Dependent Claim
17 words
A facility as claimed in claim 7 in which said detector means comprises a Hall effect transducer.
Claim 10
Dependent Claim
57 words
A facility as claimed in claim 7 in which said detector means is operable to induce a time-varying magnetic flux in said vessel wall for superimposition on the steady state magnetic flux of the permanent magnet in said boundary wall or said element and to measure changes resulting from movement of the magnet away from said wall.
Claim 11
Dependent Claim
70 words
A facility as claimed in claim 7 in which a plurality of said vessels are provided, said vessels each incorporating a device as aforesaid and being arranged in an array such that said vessel boundary walls are all accessible at one face of the array, and in which means is provided for moving the detector means from one vessel to another whereby all of the vessels can be periodically monitored.
Claim 12
Dependent Claim
38 words
A facility as claimed in claim 10 in which said moving means is operable to bring the detector means into close proximity with said boundary wall of each vessel and scan the detector means over said boundary wall.
References Cited (Backward Citations)
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Cited
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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) | 1990-07-20 | 1991-01-19 | 1991-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-20 | 1995-01-19 | 1995-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-20 | 1999-01-19 | 1999-07-21 | $7700.00 | Window Closed / Lapsed |