US3716763A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for reducing core losses in silicon steels and the like
Assignee: Allegheny Ludlum Corp
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Filing: 1971-12-29
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Granted: 1973-02-13
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Expires: 1991-12-29
Abstract
Abstract Method for reducing core losses in silicon steels and other similar materials having antiparallel domain wall structures by applying high frequency (e.g., 400-800 Hz.) oscillatory wave energy to a winding surrounding a transformer or other device using the steel or the like as a core material. Following a power surge experienced by the transformer or other electrical apparatus, the number of domain walls is reduced, increasing core losses. By applying a pulse of high frequency wave energy following the surge and at a flux density preferably in excess of 15,000 gauss, the number of domain walls can again be increased to reduce core losses.
Inventors
- 👤 G Houze
- 👤 M Osborn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 14:57
CPC Classifications
H; H01; H01F; H01F27/00; H01F27/34; H01F27/341; H01F13/00; H01F27/348
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
67 words
In the method for reducing core losses in magnetic materials normally subjected to magnetic flux produced by an exciting frequency of about 60 hertz and having antiparallel domain wall structures, the step of applying to a winding surrounding said material an alternating current having a frequency of at least 400 hertz to thereby increase the number of domain walls in said material and reduce its core loss.
Claim 2
Dependent Claim
67 words
In the method for reducing core losses in magnetic materials normally subjected to magnetic flux produced by an exciting frequency of about 60 hertz and having antiparallel domain wall structures, the step of applying to a winding surrounding said material an alternating current having a frequency of at least 400 hertz to thereby increase the number of domain walls in said material and reduce its core loss.
Claim 3
Dependent Claim
67 words
In the method for reducing core losses in magnetic materials normally subjected to magnetic flux produced by an exciting frequency of about 60 hertz and having antiparallel domain wall structures, the step of applying to a winding surrounding said material an alternating current having a frequency of at least 400 hertz to thereby increase the number of domain walls in said material and reduce its core loss.
Claim 4
Dependent Claim
67 words
In the method for reducing core losses in magnetic materials normally subjected to magnetic flux produced by an exciting frequency of about 60 hertz and having antiparallel domain wall structures, the step of applying to a winding surrounding said material an alternating current having a frequency of at least 400 hertz to thereby increase the number of domain walls in said material and reduce its core loss.
Claim 5
Dependent Claim
21 words
The method of claim 1 wherein said wave energy has a frequency in the range of about 400 to 800 hertz.
Claim 6
Dependent Claim
60 words
The method of claim 1 wherein said material is normally subjected to magnetic flux produced by a 60 hertz alternating Current generator connected to a winding surrounding said material, and including the step of disconnecting said generator from said winding before said alternating current having a frequency of at least 400 hertz is applied to a winding surrounding said material.
Claim 7
Dependent Claim
36 words
The method of claim 3 including the step of disconnecting said alternating current having a frequency of at least 400 hertz from said winding and thereafter again connecting said generator to the winding surrounding said material.
Claim 8
Dependent Claim
50 words
The method of claim 1 wherein said magnetic material is used in the core of an electrical device operated at a flux level at or below about 15,000 gauss and said alternating current of at least 400 hertz induces in said material a flux density of at least 17,000 gauss.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-13 | 1976-08-14 | 1977-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-13 | 1980-08-14 | 1981-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-13 | 1984-08-14 | 1985-02-13 | $7700.00 | Window Closed / Lapsed |