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US5280209A Expired / Lapsed US ⏱️ 0.0 years remaining

Permanent magnet structure for use in electric machinery

Assignee: United States Department of the Army
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Filing: 1989-11-14
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Granted: 1994-01-18
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Expires: 2009-11-14
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Abstract

Abstract Magnetically rigid materials are utilized to enhance the field magnitudes oduced by permanent magnet structures that are utilized in electric machinery. Magnetic circuit losses due to unnecessary magnetic fields are eliminated without employing a conventional shunt. The magnetically rigid material is cylindrically configured and magnetized to provide individual magnetic fields between sets of north and south poles on only one cylindrical surface thereof. At least one coaxial cylinder of the magnetically rigid material is included in each permanent magnet structure of the invention and each of the cylinders is constructed from a plurality of segments in one preferred embodiment thereof. Segments having a substantially triangular cross-sectional configuration are utilized in other preferred embodiments, while flux contributions from at least three segments combine to sustain each set of north and south poles in still other preferred embodiments.

Inventors

  • 👤 Herbert A. Leupold
  • 👤 II Ernest Potenziani

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 05:42
CPC Classifications
H; H02; H02K; H02K1/00; H02K1/06; H02K1/22; H02K1/27; H02K1/2706; H02K1/272; H02K1/274; H02K1/2753; H02K1/278; H02K1/2783; H02K1/12; H02K1/17

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 85 words
A permanent magnet structure for avoiding magnetic losses incurred from unutilized magnetic fields in electric machinery, comprising: at least one hollow cylinder of magnetically rigid material constructed with a plurality of segments having substantially triangular cross sections disposed in each said cylinder between segments having substantially trapezoidal cross sections, each said cylinder having a magnetic circuit which contains a plurality of magnetic fields extending from only one cylindrical surface thereof, with each said magnetic field passing between north and south poles on that cylindrical surface.
Claim 2
Dependent Claim 85 words
A permanent magnet structure for avoiding magnetic losses incurred from unutilized magnetic fields in electric machinery, comprising: at least one hollow cylinder of magnetically rigid material constructed with a plurality of segments having substantially triangular cross sections disposed in each said cylinder between segments having substantially trapezoidal cross sections, each said cylinder having a magnetic circuit which contains a plurality of magnetic fields extending from only one cylindrical surface thereof, with each said magnetic field passing between north and south poles on that cylindrical surface.
Claim 3
Dependent Claim 21 words
The magnetic structure of claim 1 wherein said magnetic fields extend only from the outer cylindrical surface of each said cylinder.
Claim 4
Dependent Claim 21 words
The magnetic structure of claim 1 wherein said magnetic fields extend only from the inner cylindrical surface of each said cylinder.
Claim 5
Dependent Claim 104 words
In electric machinery of the type having a rotor disposed within a stator and including a permanent magnetic structure for avoiding magnetic losses incurred from unutilized magnetic fields, the improvements comprising: said permanent magnetic structure includes at least one hollow cylinder of magnetically rigid material constructed with a plurality of segments having substantially triangular cross sections disposed in each said cylinder between segments having substantially trapezoidal cross sections, each said cylinder having a magnetic circuit which contains a plurality of magnetic fields extending from only one cylindrical surface thereof, with each said magnetic field passing between north and south poles on that cylindrical surface.
Claim 6
Dependent Claim 104 words
In electric machinery of the type having a rotor disposed within a stator and including a permanent magnetic structure for avoiding magnetic losses incurred from unutilized magnetic fields, the improvements comprising: said permanent magnetic structure includes at least one hollow cylinder of magnetically rigid material constructed with a plurality of segments having substantially triangular cross sections disposed in each said cylinder between segments having substantially trapezoidal cross sections, each said cylinder having a magnetic circuit which contains a plurality of magnetic fields extending from only one cylindrical surface thereof, with each said magnetic field passing between north and south poles on that cylindrical surface.
Claim 7
Dependent Claim 31 words
The electric machinery of claim 4 wherein said permanent magnet structure is incorporated on said rotor, with said magnetic fields extending only from the outer cylindrical surface of each said cylinder.
Claim 8
Dependent Claim 31 words
The electric machinery of claim 4 wherein said permanent magnet structure is incorporated on said stator, with said magnetic fields extending only from the inner cylindrical surface of each said cylinder.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-01-17 1997-07-19 1998-01-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-01-17 2001-07-19 2002-01-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-01-17 2005-07-19 2006-01-18 $7700.00 Window Closed / Lapsed

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