Patent US5233250A successfully refreshed from Google Patents.
US5233250A
Expired / Lapsed
US
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Three-phase brushless motors with half-wave control
Assignee: Industrie Magneti Marelli SRL
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Filing: 1992-02-26
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Granted: 1993-08-03
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Expires: 2012-02-26
Abstract
Abstract The motor includes a rotor with an angular array of 2n permanent magnets with a predetermined pole pitch, in which alternate magnets have opposite polarities but the same angular extent substantially equal to 2/3 of the pole pitch.
Inventors
- 👤 Pietro De Filippis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:34
CPC Classifications
H; H02; H02K; H02K29/00; H02K29/03
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
126 words
A three-phase brushless motor with a half-wave control circuit comprising a rotor having an angular array of permanent magnets each having an identical angular extent with a predetermined pole pitch wherein alternate magnets have opposite polarities and a stator separated from said rotor by an air gap and having a plurality of recesses with windings of the motor housed therein and the recesses having openings facing the air gap with each opening having a narrow angular extent, wherein the angular extent of each permanent magnet of the rotor is between a minimum value substantially equal to 2/3 of the pole pitch and a maximum value of 2/3 of the pole pitch plus 1/2 of the angular extent of the opening of each recess of the stator.
Claim 2
Dependent Claim
126 words
A three-phase brushless motor with a half-wave control circuit comprising a rotor having an angular array of permanent magnets each having an identical angular extent with a predetermined pole pitch wherein alternate magnets have opposite polarities and a stator separated from said rotor by an air gap and having a plurality of recesses with windings of the motor housed therein and the recesses having openings facing the air gap with each opening having a narrow angular extent, wherein the angular extent of each permanent magnet of the rotor is between a minimum value substantially equal to 2/3 of the pole pitch and a maximum value of 2/3 of the pole pitch plus 1/2 of the angular extent of the opening of each recess of the stator.
Claim 3
Dependent Claim
37 words
A three-phase brushless motor according to claim 1, wherein the stator includes a pack of plates of ferrous magnetic material of a size such that magnetic flux induced therein is not greater than 1 tesla in operation.
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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) | 1996-08-02 | 1997-02-01 | 1997-08-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-08-02 | 2001-02-01 | 2001-08-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-08-02 | 2005-02-01 | 2005-08-03 | $7700.00 | Window Closed / Lapsed |