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US3308374A Expired / Lapsed US ⏱️ 0.0 years remaining

Tap changing apparatus for a transformer

Assignee: Toshiba Corp
•
Filing: 1963-11-27
•
Granted: 1967-03-07
•
Expires: 1983-11-27
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Abstract

No abstract record available.

Inventors

  • 👤 Kagawa Masaaki
  • 👤 Watanabe Akira
  • 👤 Watanabe Junichi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 00:46
CPC Classifications
B; B60; B60L; B60L9/00; B60L9/02; B60L9/08; H; H01; H01F; H01F29/00; H01F29/02; H01F29/04; B60L2200/00; B60L2200/26

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 168 words
TAP CHANGING APPARATUS COMPRISING A COMBINATION OF AN ELECTRIC TRANSFORMER INCLUDING A WINDING PROVIDED WITH A PLURALITY OF VOLTAGE ADJUSTING TAPS AND CONNECTED TO BE ENERGIZED FROM A SOURCE OF ALTERNATING CURRENT, A LOAD SUPPLIED WITH A VARIABLE VOLTAGE FROM SAID TRANSFORMER, A PLURALITY OF FIRST CONTACTORS EACH ASSOCIATED WITH ONE OF SAID TAPS OF SAID TRANSFORMER WINDING TO CONNECT SAID ONE TAP TO SAID LOAD, A PAIR OF BRANCH CIRCUITS EACH INCLUDING A REACTOR WINDING AND A SECOND CONTACTOR FOR CONNECTING ALTERNATING ONES OF SAID FIRST CONTACTORS TO SAID LOAD, A THIRD CONTACTOR CONNECTED ACROSS TERMINALS OF SAID REACTOR WINDINGS WHICH ARE CLOSE TO SAID TRANSFORMER WINDING, SAID THIRD CONTACTOR BEING ARRANGED TO BE CLOSED WHEN ONE OF SAID TAPS IS SELECTED BUT OPENED DURING TAP CHANGING, A PAIR OF SEMICONDUCTOR SWITCHES CONNECTED IN REVERSE PARALLEL RELATION ACROSS THE OPPOSITE TERMINALS OF SAID REACTOR WINDINGS TO PASS POSITIVE AND NEGATIVE HALF CYCLES, RESPECTIVELY OF SAID ALTERNATING CURRENT WHEN SAID SECOND CONTACTORS ARE OPERATED DURING TAP CHANGING OPERATION.
Claim 2
Dependent Claim 168 words
TAP CHANGING APPARATUS COMPRISING A COMBINATION OF AN ELECTRIC TRANSFORMER INCLUDING A WINDING PROVIDED WITH A PLURALITY OF VOLTAGE ADJUSTING TAPS AND CONNECTED TO BE ENERGIZED FROM A SOURCE OF ALTERNATING CURRENT, A LOAD SUPPLIED WITH A VARIABLE VOLTAGE FROM SAID TRANSFORMER, A PLURALITY OF FIRST CONTACTORS EACH ASSOCIATED WITH ONE OF SAID TAPS OF SAID TRANSFORMER WINDING TO CONNECT SAID ONE TAP TO SAID LOAD, A PAIR OF BRANCH CIRCUITS EACH INCLUDING A REACTOR WINDING AND A SECOND CONTACTOR FOR CONNECTING ALTERNATING ONES OF SAID FIRST CONTACTORS TO SAID LOAD, A THIRD CONTACTOR CONNECTED ACROSS TERMINALS OF SAID REACTOR WINDINGS WHICH ARE CLOSE TO SAID TRANSFORMER WINDING, SAID THIRD CONTACTOR BEING ARRANGED TO BE CLOSED WHEN ONE OF SAID TAPS IS SELECTED BUT OPENED DURING TAP CHANGING, A PAIR OF SEMICONDUCTOR SWITCHES CONNECTED IN REVERSE PARALLEL RELATION ACROSS THE OPPOSITE TERMINALS OF SAID REACTOR WINDINGS TO PASS POSITIVE AND NEGATIVE HALF CYCLES, RESPECTIVELY OF SAID ALTERNATING CURRENT WHEN SAID SECOND CONTACTORS ARE OPERATED DURING TAP CHANGING OPERATION.

References Cited (Backward Citations)

GB827722A Cited
FR1240583A Cited
US3195038A Cited
US3176189A Cited
US3263157A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1970-03-06 1970-09-05 1971-03-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1974-03-06 1974-09-05 1975-03-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1978-03-06 1978-09-05 1979-03-07 $7700.00 Window Closed / Lapsed

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