Patent US4987398A successfully refreshed from Google Patents.
US4987398A
Expired / Lapsed
US
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Multilayered eddy current type power-saved intense AC magnetic field generator
Assignee: Kanazawa University
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Filing: 1990-01-26
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Granted: 1991-01-22
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Expires: 2010-01-26
Abstract
Abstract A conventionally arranged multilayered eddy current type intense AC magnetic field generator is remarkably improved only by intercrossing frame-shaped iron cores with alternately multilayered structure of exciting coils and conductor plates for inducing eddy currents, so as increase the impedance of the exciting coils as well as to increase the mutual inductance thereof with the conductor plates. As a result, the desired intense AC magnetic field can be efficiently and continuously generated with evidently reduced electric power.
Inventors
- 👤 Kazuo Bessho
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 01:57
CPC Classifications
H; H01; H01F; H01F7/00; H01F7/06; H01F7/20; H01F7/202
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
196 words
A multilayered eddy current type power-saved intense AC magnetic field generator comprising: a plurality of layers of exciting coils mutually engaged in coaxial state and wound with the same polarity, a plurality of layers of conductor plates alternately stacked between each layer of said exciting coils and provided commonly with slits passing through to the outskirts from central holes axially formed at central portion of said conductor plates including a connecting conductor plate provided in common with said conductor plates except said slits and hollows formed in the vicinities of said central holes and passing through with each other, and a plurality of frame-shaped magnetic materials which are formed as closed magnetic circuits surrounding cross-sections of a plurality of alternate layers of said exciting coils and said conductor plates through said hollows, so as to generate an axial-directioned intense AC magnetic field in said central holes by concentrating eddy currents induced in said conductor plates in the vicinities of said central holes along said slits by supplying an AC current to said exciting coils and to reduce the required exciting currents through the impedances of said exciting coils which are increased by said closed magnetic circuits.
Claim 2
Dependent Claim
196 words
A multilayered eddy current type power-saved intense AC magnetic field generator comprising: a plurality of layers of exciting coils mutually engaged in coaxial state and wound with the same polarity, a plurality of layers of conductor plates alternately stacked between each layer of said exciting coils and provided commonly with slits passing through to the outskirts from central holes axially formed at central portion of said conductor plates including a connecting conductor plate provided in common with said conductor plates except said slits and hollows formed in the vicinities of said central holes and passing through with each other, and a plurality of frame-shaped magnetic materials which are formed as closed magnetic circuits surrounding cross-sections of a plurality of alternate layers of said exciting coils and said conductor plates through said hollows, so as to generate an axial-directioned intense AC magnetic field in said central holes by concentrating eddy currents induced in said conductor plates in the vicinities of said central holes along said slits by supplying an AC current to said exciting coils and to reduce the required exciting currents through the impedances of said exciting coils which are increased by said closed magnetic circuits.
Claim 3
Dependent Claim
69 words
A multilayered eddy current type power-saved intense AC magnetic field generator as claimed in claim 1 wherein said exciting coils and said conductor plates are formed in cylindrical shape and alternately stacked in coaxial form, the cylindrical conductor plates being connected by said connecting conductor plate at the middle portions thereof, the cylindrical exciting coils being divided into upper side and lower side portions by said connecting conductor plate.
Claim 4
Dependent Claim
29 words
A multilayered eddy current type power-saved intense AC magnetic field generator as claimed in claim 1 wherein said exciting coils and said conductor plates are formed in rectangular shape.
Claim 5
Dependent Claim
79 words
A multilayered eddy current type power-saved intense AC magnetic field generator as claimed in claim 3 wherein a plurality of alternately stacked layers of said exciting coils and said conductor plates is divided into each one blocks and further successive three blocks are divided into each one groups in correspondence to three phase AC in inclined state, said exciting coils in each block being obliquely intercrossed with a pair of said frame-shaped magnetic materials at diagonal corners thereof respectively.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-01-21 | 1994-07-23 | 1995-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-01-21 | 1998-07-23 | 1999-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-01-21 | 2002-07-23 | 2003-01-22 | $7700.00 | Window Closed / Lapsed |