US3711744A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Passive energy dump for superconducting coil protection
Assignee: United States Atomic Energy Commission
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Filing: 1972-06-01
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Granted: 1973-01-16
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Expires: 1992-06-01
Abstract
Abstract A passive resistance type energy dump for the protection of the coils of a superconducting magnet is provided. Insertion heaters are immersed in a rigid container filled with a fusible alloy. The energy dump is connected across the coils of the superconducting magnet wherein individual heater elements are connected singly to the windings or otherwise according to the energy dumping requirements upon transition of the magnet to a normal state.
Inventors
- 👤 J Luton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 17:44
CPC Classifications
H; H01; H01F; H01F6/00; H01F6/02; H02; H02H; H02H7/00; H02H7/001; Y; Y02; Y02E; Y02E40/00; Y02E40/60; Y10; Y10S; Y10S505/00; Y10S505/825; Y10S505/85
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
185 words
A protective system for a superconducting magnet upon its transition to a normal state comprising a power supply connected to the coils of said magnet, a solenoid provided with an armature switching arm for making and breaking a circuit between said power supply and said coils, an energy dumping network connected directly across said coils, said dumping network including a pair of parallel connected diodes connected in series with a passive energy dump, and a solenoid control device connected to said solenoid for effecting a breaking of the circuit between said power supply and said coils by said solenoid switching arm in response to an abnormal operating condition associated with said coils, said passive energy dump protecting said magnet coils during their transition to normal, said dump comprising a plurality of elongated electrical heaters immersed in a fusible alloy within a rigid container, whereby said heaters and said alloy serve as an energy dump whenever excess and potentially destructive energy produced by a sudden collapse of the magnetic field of said magnet is transferred from said magnet to said heaters and their encompassing fusible alloy.
Claim 2
Dependent Claim
185 words
A protective system for a superconducting magnet upon its transition to a normal state comprising a power supply connected to the coils of said magnet, a solenoid provided with an armature switching arm for making and breaking a circuit between said power supply and said coils, an energy dumping network connected directly across said coils, said dumping network including a pair of parallel connected diodes connected in series with a passive energy dump, and a solenoid control device connected to said solenoid for effecting a breaking of the circuit between said power supply and said coils by said solenoid switching arm in response to an abnormal operating condition associated with said coils, said passive energy dump protecting said magnet coils during their transition to normal, said dump comprising a plurality of elongated electrical heaters immersed in a fusible alloy within a rigid container, whereby said heaters and said alloy serve as an energy dump whenever excess and potentially destructive energy produced by a sudden collapse of the magnetic field of said magnet is transferred from said magnet to said heaters and their encompassing fusible alloy.
Claim 3
Dependent Claim
25 words
The system set forth in claim 1, wherein each of said heaters is wound with an alloy wire whose electrical resistance increases with increasing temperature.
Claim 4
Dependent Claim
19 words
The system set forth in claim 2, wherein said alloy wire is 70 percent nickel and 30 percent iron.
Claim 5
Dependent Claim
34 words
The system set forth in claim 2, wherein said electrical heaters are 1 inch in diameter, 8 inches long and are sheathed, and said fusible alloy is an eutectic mixture of bismuth and lead.
Claim 6
Dependent Claim
24 words
The system set forth in claim 4, wherein the number of said heaters is at least 16 comprising 4 rows of four heaters each.
Claim 7
Dependent Claim
58 words
The system set forth in claim 5, wherein said magnet coils are quadrupole coils connected in series with said power supply, and said heaters are connected in parallel with each other and in series with said diodes across said coils to provide a dumping current capacity of at least 830 amperes for the protection of said magnet coils.
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) | 1976-01-16 | 1976-07-17 | 1977-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-16 | 1980-07-17 | 1981-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-16 | 1984-07-17 | 1985-01-16 | $7700.00 | Window Closed / Lapsed |