Patent US5825112A successfully refreshed from Google Patents.
US5825112A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Doubly salient motor with stationary permanent magnets
Assignee: Electric Power Research Institute
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Filing: 1992-08-06
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Granted: 1998-10-20
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Expires: 2012-08-06
Abstract
Abstract A new class of doubly-salient motors which incorporate a specific stator/rotor pole arrangement and stationary permanent magnets mounted in the stator to provide a linearly increasing flux linkage over the entire area of pole overlap. The new motors provide greater output torque, higher efficiency, quicker response, and a simpler structure in comparison to conventional reluctance motors.
Inventors
- 👤 Thomas A. Lipo
- 👤 Yuefeng Liao
- 👤 Feng Liang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:58
CPC Classifications
H; H02; H02K; H02K19/00; H02K19/02; H02K19/10; H02K19/103; H02K19/16; H02K19/22; H02K19/24; H02K21/00; H02K21/38; H02K21/44; H02K29/00; H02K29/03
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
192 words
A permanent magnet motor comprising: a rotor mounted for rotation about a central axis, said rotor further comprising, a plurality of salient rotor poles spaced at equal angular intervals around said central axis; and a stator symmetrically formed around said central axis so as to encircle said rotor, said stator further comprising, a plurality of salient stator poles spaced at equal angular intervals around said central axis, said stator poles being arranged with respect to said rotor poles to provide a constant air-gap reluctance during rotation of said rotor within said stator, and a plurality of permanent magnets shaped in two elongate parallelepipeds parallely spaced and symmetrically positioned within said stator in the plane of said central axis, each of said parallelopipeds being positioned between a pair of said stator poles on diametric sides of said central axis, said magnets being so polarized as magnetize as north magnetic poles the ones of said stator poles lying to one side of the plane containing said magnets and to magnetize as south magnetic poles the ones of said stator poles lying to the side opposite said one side of the plane containing said magnets.
Claim 2
Dependent Claim
192 words
A permanent magnet motor comprising: a rotor mounted for rotation about a central axis, said rotor further comprising, a plurality of salient rotor poles spaced at equal angular intervals around said central axis; and a stator symmetrically formed around said central axis so as to encircle said rotor, said stator further comprising, a plurality of salient stator poles spaced at equal angular intervals around said central axis, said stator poles being arranged with respect to said rotor poles to provide a constant air-gap reluctance during rotation of said rotor within said stator, and a plurality of permanent magnets shaped in two elongate parallelepipeds parallely spaced and symmetrically positioned within said stator in the plane of said central axis, each of said parallelopipeds being positioned between a pair of said stator poles on diametric sides of said central axis, said magnets being so polarized as magnetize as north magnetic poles the ones of said stator poles lying to one side of the plane containing said magnets and to magnetize as south magnetic poles the ones of said stator poles lying to the side opposite said one side of the plane containing said magnets.
Claim 3
Dependent Claim
33 words
The permanent magnet motor of claim 1, wherein said plurality of stator poles further comprises a multiple of six stator poles evenly spaced at angular intervals equal to a multiple of π/3 radians.
Claim 4
Dependent Claim
22 words
The permanent magnet motor of claim 2, wherein said stator poles have a pole arc equal to a multiple of π/6 radians.
Claim 5
Dependent Claim
33 words
The permanent magnet motor of claim 2, wherein said plurality of rotor poles further comprise a multiple of four rotor poles evenly spaced at angular intervals equal to a multiple of π/2 radians.
Claim 6
Dependent Claim
22 words
The permanent magnet motor of claim 4, wherein said rotor poles have a pole arc equal to a multiple of π/6 radians.
Claim 7
Dependent Claim
31 words
The permanent magnet motor of claim 4, wherein said permanent magnets each have planar faces which are angularly displaced by a multiple of π/6 radians from one of said stator poles.
Claim 8
Dependent Claim
34 words
The permanent magnet motor of claim 4, wherein said stator further comprises a plurality of stator windings corresponding to an equal number of phases, each stator winding being coiled around two diametric stator poles.
Claim 9
Dependent Claim
180 words
A permanent magnet motor comprising: a rotor mounted for rotation about a central axis, said rotor having four salient rotor poles spaced at equal angular intervals around said central axis; and a stator symmetrically formed around said central axis so as to encircle said rotor, said stator having six salient stator poles spaced at equal angular intervals around said central axis, and three stator windings corresponding to three phases, each said stator winding being coiled around two diametric stator poles, said stator further comprising a plurality of permanent magnets shaped in two elongate parallelepipeds parallelly spaced and symmetrically positioned within said stator in the plane of said central axis, each of said parallelopipeds being positioned between a pair of said stator poles on diametric sides of said stator, said magnets being so polarized as magnetize as north magnetic poles three of said stator poles lying to one side of the plane containing said magnets and to magnetize as south magnetic poles three of said stator poles lying to the side opposite said one side of the plane containing said magnets.
Claim 10
Dependent Claim
180 words
A permanent magnet motor comprising: a rotor mounted for rotation about a central axis, said rotor having four salient rotor poles spaced at equal angular intervals around said central axis; and a stator symmetrically formed around said central axis so as to encircle said rotor, said stator having six salient stator poles spaced at equal angular intervals around said central axis, and three stator windings corresponding to three phases, each said stator winding being coiled around two diametric stator poles, said stator further comprising a plurality of permanent magnets shaped in two elongate parallelepipeds parallelly spaced and symmetrically positioned within said stator in the plane of said central axis, each of said parallelopipeds being positioned between a pair of said stator poles on diametric sides of said stator, said magnets being so polarized as magnetize as north magnetic poles three of said stator poles lying to one side of the plane containing said magnets and to magnetize as south magnetic poles three of said stator poles lying to the side opposite said one side of the plane containing said magnets.
Claim 11
Dependent Claim
33 words
The permanent magnet motor of claim 8, wherein said rotor poles are arranged with respect to said stator poles to provide a constant air-gap reluctance during rotation of said rotor within said stator.
Claim 12
Dependent Claim
20 words
The permanent magnet motor of claim 9, wherein said stator poles are equally spaced at angular intervals of π/3 radians.
Claim 13
Dependent Claim
18 words
The permanent magnet motor of claim 10, wherein said stator poles have a pole arc of π/6 radians.
Claim 14
Dependent Claim
20 words
The permanent magnet motor of claim 11, wherein said rotor poles are equally spaced at angular intervals of π/2 radians.
Claim 15
Dependent Claim
23 words
The permanent magnet motor of claim 12, wherein said rotor poles have a pole arc equal to or slightly greater than π/6 radians.
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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) | 2001-10-19 | 2002-04-20 | 2002-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-10-19 | 2006-04-20 | 2006-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-10-19 | 2010-04-20 | 2010-10-20 | $7700.00 | Window Closed / Lapsed |