Patent US3849705A successfully refreshed from Google Patents.
US3849705A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluid-cooled transformer having a temperature responsive indicating and controlling device
Assignee: ABB Inc USA
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Filing: 1973-07-11
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Granted: 1974-11-19
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Expires: 1993-07-11
Abstract
Abstract Temperature responsive device suitable for use with air-cooled power transformers. The temperature responsive device indicates the temperature at a predetermined location within the transformer and controls the activation of fans, alarms, and circuit breakers associated with the transformer. Electrical isolation between a temperature sensing element and the controlled auxiliary apparatus is provided by light channels across which the control information is transmitted.
Inventors
- 👤 D Mcelroy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:07
CPC Classifications
H; H01; H01F; H01F27/00; H01F27/40; H01F27/402; H01F27/406; H02; H02H; H02H5/00; H02H5/04; H02H5/046
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
240 words
A fluid-cooled transformer comprising the combination of: a core and coil assembly; temperature responsive means located within the transformer coil; means for forcing the cooling fluid around said core and coil assembly, said forcing means being controlled by said temperature responsive means; a first comparator circuit which is responsive to the temperature of said temperature responsive means, said first comparator circuit being constructed to activate the forcing means at a first predetermined temperature and to deactivate the forcing means at a second predetermined temperature of said temperature responsive means; means for providing an alarm if the temperature in the coil becomes excessively high, said indicating means being activated by said temperature responsive means; a second comparator circuit which is responsive to the temperature of said temperature responsive means, said second comparator circuit being constructed to activate the alarm means at a third predetermined temperature of said temperature responsive means; means for interrupting the load power delivered by the transformer, said interrupting means being activated by said temperature responsive means; and, a third comparator circuit which is responsive to the temperature of said temperature responsive means, said third comparator circuit being constructed to activate the reducing means at a fourth predetermined temperature of said temperature responsive means; said temperature responsive means being isolated from the forcing, alarm, and interrupting means to prevent the transfer of any high voltages existing on the temperature responsive means to the forcing, alarm or interrupting means.
Claim 2
Dependent Claim
240 words
A fluid-cooled transformer comprising the combination of: a core and coil assembly; temperature responsive means located within the transformer coil; means for forcing the cooling fluid around said core and coil assembly, said forcing means being controlled by said temperature responsive means; a first comparator circuit which is responsive to the temperature of said temperature responsive means, said first comparator circuit being constructed to activate the forcing means at a first predetermined temperature and to deactivate the forcing means at a second predetermined temperature of said temperature responsive means; means for providing an alarm if the temperature in the coil becomes excessively high, said indicating means being activated by said temperature responsive means; a second comparator circuit which is responsive to the temperature of said temperature responsive means, said second comparator circuit being constructed to activate the alarm means at a third predetermined temperature of said temperature responsive means; means for interrupting the load power delivered by the transformer, said interrupting means being activated by said temperature responsive means; and, a third comparator circuit which is responsive to the temperature of said temperature responsive means, said third comparator circuit being constructed to activate the reducing means at a fourth predetermined temperature of said temperature responsive means; said temperature responsive means being isolated from the forcing, alarm, and interrupting means to prevent the transfer of any high voltages existing on the temperature responsive means to the forcing, alarm or interrupting means.
Claim 3
Dependent Claim
41 words
The fluid-cooled transformer of claim 1 wherein the first predetermined temperature is higher than the second predetermined temperature, the third predetermined temperature is higher than the first predetermined temperature, and the fourth predetermined temperature is higher than the third predetermined temperature.
Claim 4
Dependent Claim
46 words
The fluid-cooled transformer of claim 1 wherein the forcing, alarm, and interrupting means each include a light generator and a light detector which is responsive to said light generator, with the isolation being provided by the light channel between said light generator and said light detector.
Claim 5
Dependent Claim
28 words
The fluid cooled transformer of claim 3 including an isolation transformer which isolates the power supplied to the first, second and third comparator circuits from the power source.
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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) | 1977-11-18 | 1978-05-20 | 1978-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-18 | 1982-05-20 | 1982-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-18 | 1986-05-20 | 1986-11-19 | $7700.00 | Window Closed / Lapsed |