US3736440A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit breaker
Assignee: Fuji Electric Co Ltd
•
Filing: 1971-10-08
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Granted: 1973-05-29
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Expires: 1991-10-08
Abstract
Abstract Disclosed herein is a circuit breaker comprising as its constructive elements, an insulation transformer adapted to supply an electric power from the ground potential portion to a control device placed on a high potential portion, or a current transformer connected to a line potential portion, a stray capacity of the insulation transformer or current transformer being skillfully utilized whereby measurement or observation of a system voltage can be readily achieved without use of a separate capacitor type potential divider for measuring a voltage between contacts of the circuit breaker.
Inventors
- 👤 Y Nitta
- 👤 N Kiyokuni
- 👤 K Kawasaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 13:00
CPC Classifications
H; H01; H01H; H01H33/00; H01H33/02; H01H33/59; H01H33/593
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
84 words
A circuit breaker comprising an insulation transformer provided therein and adapted to supply an electric power from a ground potential portion to a control device placed on a high potential portion; a capacitor which is connected so as to electrically compose a series circuit with a stray electrostatic capacity present between the ground potential portion and the high potential portion of said insulation transformer; and means adapted to detect a voltage produced between both terminals of said capacitor, thereby to measure a system voltage.
Claim 2
Dependent Claim
84 words
A circuit breaker comprising an insulation transformer provided therein and adapted to supply an electric power from a ground potential portion to a control device placed on a high potential portion; a capacitor which is connected so as to electrically compose a series circuit with a stray electrostatic capacity present between the ground potential portion and the high potential portion of said insulation transformer; and means adapted to detect a voltage produced between both terminals of said capacitor, thereby to measure a system voltage.
Claim 3
Dependent Claim
45 words
A circuit breaker according to claim 1, which comprises additionally a synchronous control device which employs as its input said voltage between both terminals of said capacitor so that the circuit breaker can be closed with a particular phase and polarity of the system voltage.
Claim 4
Dependent Claim
70 words
A circuit breaker according to claim 1, in which the circuit breaker consists of at least two circuit breaker units series-connected with respect to the line, each of said units causing a first voltage and a second voltage between both terminals of said capacitor, said first voltage being utilized to carry out a synchronous closing of the circuit breaker, and said second voltage being utilized to measure the system voltage.
Claim 5
Dependent Claim
58 words
A circuit breaker according to claim 2, in which a contact to be closed by a closing signal is connected in series to one of both terminals of said capacitor at the position between a synchronous control device and said capacitor, whereby the synchronous control device is made to be operated by the closing operation of said contact.
Claim 6
Dependent Claim
55 words
A circuit breaker according to claim 2, in which a detector adapted to detect the polarity of a residual voltage on the line is connected to both terminals of said capacitor, said detector having an output contact causing operation of the synchronous control device, thereby to close the circuit breaker, with a particular voltage polarity.
Claim 7
Dependent Claim
35 words
A circuit breaker according to claim 2, in which there are provided three kinds of timing eleMents adapted to automatically correct a synchronous closing point variation caused by frequency variaton on a transmission power system.
Claim 8
Dependent Claim
45 words
A circuit breaker according to claim 2, in which said capacitor is provided with another capacitor connected in series thereto, an output voltage produced across both terminals of said another capacitor being utilized to measure the system voltage or to carry out a switching indication.
Claim 9
Dependent Claim
94 words
A circuit breaker which comprises a current transformer connected to a transmission line surrounded at both sides by a breaking contact and adapted to supply a current from said transmission line to a control device placed at the ground potential portion, a capacitor which is connected so as to electrically compose a series circuit with a stray electrostatic capacity present between the ground potential portion and the high potential portion of said current transformer, and means adapted to detect a voltage produced between said terminals of said capacitor thereby to measure a system voltage.
Claim 10
Dependent Claim
94 words
A circuit breaker which comprises a current transformer connected to a transmission line surrounded at both sides by a breaking contact and adapted to supply a current from said transmission line to a control device placed at the ground potential portion, a capacitor which is connected so as to electrically compose a series circuit with a stray electrostatic capacity present between the ground potential portion and the high potential portion of said current transformer, and means adapted to detect a voltage produced between said terminals of said capacitor thereby to measure a system voltage.
References Cited (Backward Citations)
US3315147A
Cited
US3315056A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-28 | 1976-11-27 | 1977-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-28 | 1980-11-27 | 1981-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-28 | 1984-11-27 | 1985-05-29 | $7700.00 | Window Closed / Lapsed |