US3766006A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rapidly refuelable nuclear reactor
Assignee: Westinghouse Electric Corp
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Filing: 1970-07-08
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Granted: 1973-10-16
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Expires: 1990-07-08
Abstract
Abstract A nuclear reactor in which the control rods are held withdrawn or retracted from the fuel by a permanent magnet during refueling. The reactor includes a missile shield which restrains the control rod units from being ejected upwardly during normal operation of the reactor. During refueling the shield is retracted. During normal operation the control rods, when withdrawn, are held by an electromagnet whose coil may be readily deenergized for rod insertion at any time. During refueling the retraction of the shield causes a permanent magnet to replace the electromagnet core.
Inventors
- 👤 E Frisch
- 👤 H Andrews
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:03
CPC Classifications
G; G21; G21C; G21C7/00; G21C7/06; G21C7/08; G21C7/12; G21C19/00; G21C19/02; G21C19/12; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
228 words
A nuclear reactor comprising a pressure vessel containing a core having stationary fuel elements and vertically movable control rods in the core, multiple clusters of control rod drive mechanisms surmounting said pressure vessel, each of said drive mechanisms including a housing having multiple cylinders therein, a piston in each of said cylinders, and a drive rod connecting each piston with at least one control rod, the improvement comprising: assemblies mounted on each housing, each assembly being mounted in a position outwardly from each of said cylinders and extending parallel thereto: electromagnetic means removably mounted on each assembly and in a position opposite said piston when the control rods are withdrawn from the core; a plunger reciprocally movable in said electromagnetic means; said plunger including a shaft having a magnetizable material and permanently magnetized material thereon, and means associated with each assembly for selectively moving said magnetizable material or said permanently magnetized material on the plunger into said electromagnetic means and in magnetic coupling relationship with said piston, the arrangement being such that when the magnetizable material is in the electromagnetic means and the latter is energized, magnetic flux acts to hold the piston in a stationary position, and when the permanently magnetized material is in the electromagnetic means and the latter is not energized, magnetic flux from the permanently magnetized material holds the piston in a stationary position.
Claim 2
Dependent Claim
228 words
A nuclear reactor comprising a pressure vessel containing a core having stationary fuel elements and vertically movable control rods in the core, multiple clusters of control rod drive mechanisms surmounting said pressure vessel, each of said drive mechanisms including a housing having multiple cylinders therein, a piston in each of said cylinders, and a drive rod connecting each piston with at least one control rod, the improvement comprising: assemblies mounted on each housing, each assembly being mounted in a position outwardly from each of said cylinders and extending parallel thereto: electromagnetic means removably mounted on each assembly and in a position opposite said piston when the control rods are withdrawn from the core; a plunger reciprocally movable in said electromagnetic means; said plunger including a shaft having a magnetizable material and permanently magnetized material thereon, and means associated with each assembly for selectively moving said magnetizable material or said permanently magnetized material on the plunger into said electromagnetic means and in magnetic coupling relationship with said piston, the arrangement being such that when the magnetizable material is in the electromagnetic means and the latter is energized, magnetic flux acts to hold the piston in a stationary position, and when the permanently magnetized material is in the electromagnetic means and the latter is not energized, magnetic flux from the permanently magnetized material holds the piston in a stationary position.
Claim 3
Dependent Claim
33 words
The combination according to claim 1 wherein the plunger shaft is guided during movement in an enclosure; and spring means in said enclosure for biasing the magnetizable material out of said electromagnetic means.
Claim 4
Dependent Claim
81 words
The combination according to claim 1 wherein said electromagnetic means comprises a coil mounted on said assembly and said plunger is adapted for movement in said coil; and magnetic means on opposite sides of said coil in alignment with a magnetic material in the walls of said housing, said magnetic means and magnetic material comprising a path for flux generated by said coil which links the piston to hold its attached control rod out of neutron controlling relationship with said core.
Claim 5
Dependent Claim
105 words
The combination according to claim 1 wherein the means associated with each assembly comprises a device movably mounted on said housing; a missile shield surmounting said reactor; means interconnecting the missile shield with said device; and means on the reactor for raising the shield vertically, the arrangement being such that when the shield is in its lower position, the interconnecting means cooperates with said device to hold the magnetizable material on the plunger in the electromagnetic means, and when the shield is raised, the interconnecting means permits upward movement of the plunger to permit the permanently magnetized material to be positioned in the electromagnetic means.
Claim 6
Dependent Claim
95 words
The combination according to claim 3 wherein a spring is positioned in said assembly and engages one end of said plunger to bias the magnetizable material in a direction out of the coil; a missile shield surmounting said reactor; means on said reactor for raising the shield vertically; and means interconnecting the missile shield with said plunger so that when the shield is raised, the magnetizable material on the plunger is moved out of the coil and the permanently magnetized material is moved into said coil and into a magnetic coupling arrangement with the piston.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-15 | 1977-04-16 | 1977-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-15 | 1981-04-16 | 1981-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-15 | 1985-04-16 | 1985-10-16 | $7700.00 | Window Closed / Lapsed |