Patent US4381284A successfully refreshed from Google Patents.
US4381284A
Expired / Lapsed
US
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Fuel assembly for a nuclear reactor
Assignee: Westinghouse Electric Corp
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Filing: 1980-12-16
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Granted: 1983-04-26
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Expires: 2000-12-16
Abstract
Abstract A fuel assembly in a nuclear reactor comprises a locking mechanism that is capable of locking the fuel assembly to the core plate of a nuclear reactor to prevent inadvertent movement of the fuel assembly. The locking mechanism comprises a ratchet mechanism that allows the fuel assembly to be easily locked to the core plate but prevents unlocking except when the ratchet is disengaged.
Inventors
- 👤 Robert K. Gjertsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:33
CPC Classifications
G; G21; G21C; G21C3/00; G21C3/30; G21C3/32; G21C3/33; G21C3/3305; G21C3/3315; G21C5/00; G21C5/02; G21C5/06; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
93 words
A fuel assembly for a nuclear reactor comprising: a top nozzle; a bottom nozzle; a plurality of fuel elements containing nuclear fuel disposed between said top nozzle and said bottom nozzle; a guide tube extending from said top nozzle to said bottom nozzle; a lower member attached to the lower end of said guide tube and having external threads thereon for engagement the core plate of said nuclear reactor thereby attaching said fuel assembly to said core plate; and locking means attached to said top nozzle for preventing disengagement of said external threads.
Claim 2
Dependent Claim
93 words
A fuel assembly for a nuclear reactor comprising: a top nozzle; a bottom nozzle; a plurality of fuel elements containing nuclear fuel disposed between said top nozzle and said bottom nozzle; a guide tube extending from said top nozzle to said bottom nozzle; a lower member attached to the lower end of said guide tube and having external threads thereon for engagement the core plate of said nuclear reactor thereby attaching said fuel assembly to said core plate; and locking means attached to said top nozzle for preventing disengagement of said external threads.
Claim 3
Dependent Claim
58 words
The fuel assembly according to claim 1 wherein said locking means comprises: a slider member having first teeth thereon and slidably disposed on said guide tube; and a retainer housing having second teeth thereon and attached to said top nozzle, said first teeth and said second teeth being arranged to prevent rotation of said guide tube when engaged.
Claim 4
Dependent Claim
26 words
The fuel assembly according to claim 2 wherein said locking means further comprises biasing means for urging said second teeth into engagement with said first teeth.
Claim 5
Dependent Claim
53 words
The fuel assembly according to claim 3 wherein said locking means further comprises a slotted member attached to said guide tube and in contact with said slider member for preventing rotation of said slider member with respect to said guide tube but allowing said slider member to slide relative to said slotted member.
Claim 6
Dependent Claim
31 words
The fuel assembly according to claim 4 wherein said second teeth are arranged to override said first teeth when it is desired to engage said lower member to said core plate.
Claim 7
Dependent Claim
34 words
The fuel assembly according to claim 5 wherein said second teeth are arranged to prevent said second teeth from overriding said first teeth for preventing disengagement of said lower member from said core plate.
Claim 8
Dependent Claim
41 words
The fuel assembly according to claim 6 wherein said fuel assembly further comprises a spring washer disposed on said bottom nozzle near said lower member for preventing loss of axial preload on said guide tube when said spring washer is compressed.
Claim 9
Dependent Claim
20 words
The fuel assembly according to claim 7 wherein said guide tube is rotatably and slidably disposed in said top nozzle.
Claim 10
Dependent Claim
24 words
The fuel assembly according to claim 8 wherein said lower member is a stainless steel member and said guide tube is a Zircaloy member.
Claim 11
Dependent Claim
15 words
The fuel assembly according to claim 9 wherein said biasing means is a coil spring.
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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) | 1986-04-25 | 1986-10-25 | 1987-04-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-04-25 | 1990-10-25 | 1991-04-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-04-25 | 1994-10-25 | 1995-04-26 | $7700.00 | Window Closed / Lapsed |