Patent US6239525B1 successfully refreshed from Google Patents.
US6239525B1
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US
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Permanent magnet dynamoelectric rotating machine and electric vehicle equipped with the same
Assignee: Hitachi Ltd
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Filing: 2000-02-04
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Granted: 2001-05-29
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Expires: 2020-02-04
Abstract
Abstract A permanent magnet dynamoelectric rotating machine comprises a stator provided with windings; and a rotor disposed with an air gap between the stator and the rotor, and provided with a plurality of permanent magnets arranged along the circumference of the rotor and fixed to the rotor. The circumferential length of a surface of each permanent magnet facing the stator is determined so that an induced voltage has a waveform approximate to a sinusoidal waveform to suppress the peak of the induced voltage.
Inventors
- 👤 Yutaka Matsunobu
- 👤 Fumio Tajima
- 👤 Takashi Kobayashi
- 👤 Shouichi Kawamata
- 👤 Suetaro Shibukawa
- 👤 Osamu Koizumi
- 👤 Keiji Oda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:45
CPC Classifications
H; H02; H02K; H02K1/00; H02K1/06; H02K1/22; H02K1/27; H02K1/2706; H02K1/272; H02K1/274; H02K1/2753; H02K1/278; Y; Y02; Y02T; Y02T10/00; Y02T10/60; Y02T10/64
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
134 words
A permanent magnet electric machine comprising: a stator provided with windings thereon; and a rotor disposed with an air gap between the stator and the rotor, and having a plurality of permanent magnets fixed along a circumference thereof, with spacing between adjacent magnets; wherein a circumferential extent of surfaces of the permanent magnets facing the stator is selected so that an induced voltage in the machine has a waveform which approximates a sinusoidal waveform; and an angle θ, whose sides are radii of the rotor passing through opposite circumferential ends of a surface of each permanent magnet which is nearer to the stators, is smaller than an angle ψ, whose sides are radii of the rotor passing through opposite circumferential ends of a surface of each permanent magnet which is farther from the stator.
Claim 2
Dependent Claim
134 words
A permanent magnet electric machine comprising: a stator provided with windings thereon; and a rotor disposed with an air gap between the stator and the rotor, and having a plurality of permanent magnets fixed along a circumference thereof, with spacing between adjacent magnets; wherein a circumferential extent of surfaces of the permanent magnets facing the stator is selected so that an induced voltage in the machine has a waveform which approximates a sinusoidal waveform; and an angle θ, whose sides are radii of the rotor passing through opposite circumferential ends of a surface of each permanent magnet which is nearer to the stators, is smaller than an angle ψ, whose sides are radii of the rotor passing through opposite circumferential ends of a surface of each permanent magnet which is farther from the stator.
Claim 3
Dependent Claim
20 words
The permanent magnet dynamoelectric rotating machine according to claim 1 , wherein the permanent magnets have a trapezoidal cross section.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-05-28 | 2004-11-27 | 2005-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-05-28 | 2008-11-27 | 2009-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-05-28 | 2012-11-27 | 2013-05-29 | $7700.00 | Window Closed / Lapsed |