Patent US3934174A successfully refreshed from Google Patents.
US3934174A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Surge voltage protection for transfer switches for load-tap changers
Assignee: Scheubeck GmbH and Co
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Filing: 1974-08-15
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Granted: 1976-01-20
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Expires: 1994-08-15
Abstract
Abstract A transfer switch for load-tap changers of the Jansen-type is provided with a non-linear surge voltage protective resistor forming a shunt across two taps of a tapped transformer winding and arranged in such a way that a breakdown of the resistor does not result in a short-circuit across the section of the tapped winding situated between the two taps.
Inventors
- 👤 Alexander Bleibtreu
- 👤 Wolfgang Breuer
- 👤 Hans-Henning Mieske
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 04:49
CPC Classifications
H; H01; H01H; H01H33/00; H01H33/02; H01H33/04; H01H33/16; H01H33/161; B; B65; B65H; B65H27/00; H01F; H01F29/00; H01F29/02; H01F29/025; H01F29/04; H01H9/00; H01H9/0005
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
216 words
In a transfer switch for load-tap changers the combination of a. a pair of terminals for connecting the contact means of the transfer switch to a pair of taps of a tapped transformer winding; b. a pair of relatively movable switch-over contact means each arranged to connect selectively each of said pair of terminals to an outgoing load-current-carrying line; c. a pair of switch-over resistors each interposed between one of said pair of terminals and one of said pair of switch-over contact means; d. a pair of relatively movable current-carrying contact means each shunted across one of said pair of switch-over contact means to connect selectively each of said pair of terminals directly with said outgoing load-current-carrying line; e. a tank with a body of insulating fluid therein housing said pair of switch-over contact means and said pair of current-carrying contact means; and f. a non-linear surge voltage protective resistor arranged inside said tank submersed in said body of insulating fluid and interconnecting the ends of said pair of switch-over resistors remote from said pair of terminals and adjacent said pair of switch-over contact means so that in case of breakdown of said surge protective resistor the current resulting from a voltage applied across said pair of terminals is limited by said pair of switch-over resistors.
Claim 2
Dependent Claim
216 words
In a transfer switch for load-tap changers the combination of a. a pair of terminals for connecting the contact means of the transfer switch to a pair of taps of a tapped transformer winding; b. a pair of relatively movable switch-over contact means each arranged to connect selectively each of said pair of terminals to an outgoing load-current-carrying line; c. a pair of switch-over resistors each interposed between one of said pair of terminals and one of said pair of switch-over contact means; d. a pair of relatively movable current-carrying contact means each shunted across one of said pair of switch-over contact means to connect selectively each of said pair of terminals directly with said outgoing load-current-carrying line; e. a tank with a body of insulating fluid therein housing said pair of switch-over contact means and said pair of current-carrying contact means; and f. a non-linear surge voltage protective resistor arranged inside said tank submersed in said body of insulating fluid and interconnecting the ends of said pair of switch-over resistors remote from said pair of terminals and adjacent said pair of switch-over contact means so that in case of breakdown of said surge protective resistor the current resulting from a voltage applied across said pair of terminals is limited by said pair of switch-over resistors.
Claim 3
Dependent Claim
136 words
A polyphase transfer switch as specified in claim 1 wherein a. said pair of relatively movable switch-over contact means and said pair of current-carrying contact means are arranged inside of a cylindrical tank and operable by a driving shaft arranged in coaxial relation to said tank; b. a cylinder of electric insulating material is arranged inside of and in coaxial relation to said tank; c. said pair of switch-over resistors for each of the phases of said transfer switch are arranged inside the annular space bounded by said tank and said cylinder of insulating material; and wherein d. said non-linear voltage surge protective resistor for each of the phases of said transfer switch is in the form of a column arranged inside said cylinder of insulating material and parallel to and spaced from the axis thereof.
References Cited (Backward Citations)
US3174097A
Cited
US3813503A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-01-19 | 1979-07-21 | 1980-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-19 | 1983-07-21 | 1984-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-19 | 1987-07-21 | 1988-01-20 | $7700.00 | Window Closed / Lapsed |