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US4032837A Expired / Lapsed US ⏱️ 0.0 years remaining

Current transformer

Assignee: Kymmene Oy
•
Filing: 1976-02-10
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Granted: 1977-06-28
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Expires: 1996-02-10
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Abstract

Abstract A current transformer comprising a tubular main insulator, a number of first windings arranged around the main insulator, and a number of second windings arranged inside the main insulator. The second windings are arranged opposite their corresponding first windings so that the pairs of windings formed in this way are, in the direction of the axis of the main insulator, at a distance from each other. The primary windings are connected in series. A magnetic circuit related to each pair of windings consists of a first core portion that surrounds each first winding from the outside and has yoke portions, and of a second core portion covering each second winding and the main insulator from the inside and has likewise yoke portions. The subsequent cores, or core portions, have common intermediate yoke portions and the primary windings are arranged so as to magnetize both cores in the same direction.

Inventors

  • 👤 Kalevi Panu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 07:44
CPC Classifications
H; H01; H01F; H01F27/00; H01F27/34; H01F30/00; H01F30/06; H01F30/10; H01F38/00; H01F38/20; H01F38/22; H01F38/28

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 154 words
A current transformer comprising: a tubular main insulator, at least two first windings (either primary or secondary windings) arranged around the main insulator, at least two second windings (either secondary or primary windings) arranged inside the main insulator preferably opposite corresponding first windings so that the pairs of windings formed in this way are, in the direction of the axis of the main insulator, at a distance from each other, whereby the primary windings are connected in series, and a magnetic circuit related to each pair of windings, comprising a first core portion that surrounds each first winding and the main insulator from the outside and has yoke portions, and a second core portion covering each second winding and the main insulator from the inside and has yoke portions, wherein subsequent core portions have common intermediate yoke portions and the primary windings are arranged so as to magnetize both cores in the same direction.
Claim 2
Dependent Claim 154 words
A current transformer comprising: a tubular main insulator, at least two first windings (either primary or secondary windings) arranged around the main insulator, at least two second windings (either secondary or primary windings) arranged inside the main insulator preferably opposite corresponding first windings so that the pairs of windings formed in this way are, in the direction of the axis of the main insulator, at a distance from each other, whereby the primary windings are connected in series, and a magnetic circuit related to each pair of windings, comprising a first core portion that surrounds each first winding and the main insulator from the outside and has yoke portions, and a second core portion covering each second winding and the main insulator from the inside and has yoke portions, wherein subsequent core portions have common intermediate yoke portions and the primary windings are arranged so as to magnetize both cores in the same direction.
Claim 3
Dependent Claim 15 words
A current transformer as claimed in claim 1, wherein the secondary windings are substantially identical.
Claim 4
Dependent Claim 50 words
A current transformer as claimed in claim 1, wherein the secondary windings are, at either corresponding end, galvanically connected together, said transformer further comprising a capacitor connected between the free ends of the secondary windings, which capacitor is dimensioned so as to compensate the magnetic resistance of the intermediate yoke.
Claim 5
Dependent Claim 20 words
A current transformer as claimed in claim 3, wherein the secondary windings are galvanically connected together by means of earthing.

References Cited (Backward Citations)

US3792396A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-06-27 1980-12-27 1981-06-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-06-27 1984-12-27 1985-06-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-06-27 1988-12-27 1989-06-28 $7700.00 Window Closed / Lapsed

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