Patent US3836801A successfully refreshed from Google Patents.
US3836801A
Expired / Lapsed
US
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Stator for dc machines
Assignee: Hitachi Ltd
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Filing: 1973-03-07
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Granted: 1974-09-17
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Expires: 1993-03-07
Abstract
Abstract A stator of a DC machine comprising at least a pair of magnetic poles extending radially at a small distance to the peripheral portion of the armature and arranged equidistantly from each other, and at least two magnets each interposed between the magnetic poles in the manner so that each magnetic pole is sandwiched between the poles of the same polarity of those of the magnets which hold the magnetic pole therebetween.
Inventors
- 👤 S Yamashita
- 👤 K Onishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:07
CPC Classifications
H; H02; H02K; H02K23/00; H02K23/02; H02K23/04
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
133 words
A stator of a direct-current machine having an armature, said stator comprising at least a pair of magnetic poles extending radially at a small distance to the outer periphery of the armature and arranged equidistantly to each other, and at least two magnets each interposed between said magnetic poles in the manner so that each of said magnetic poles is sandwiched between the poles of the same polarity of those of said magnets which hold said each of said magnetic poles therebetween, each of said magnets including at least two magnet units disposed in parallel between said magnetic poles, the inner magnet unit of the two disposed nearer to said armature having a larger coercive force than the outer magnet unit of the two disposed nearer to the outer periphery of the machine.
Claim 2
Dependent Claim
133 words
A stator of a direct-current machine having an armature, said stator comprising at least a pair of magnetic poles extending radially at a small distance to the outer periphery of the armature and arranged equidistantly to each other, and at least two magnets each interposed between said magnetic poles in the manner so that each of said magnetic poles is sandwiched between the poles of the same polarity of those of said magnets which hold said each of said magnetic poles therebetween, each of said magnets including at least two magnet units disposed in parallel between said magnetic poles, the inner magnet unit of the two disposed nearer to said armature having a larger coercive force than the outer magnet unit of the two disposed nearer to the outer periphery of the machine.
Claim 3
Dependent Claim
31 words
A stator of a direct-current machine according to claim 2, in which said inner magnet unit consists of a ferrite material and said outer magnet unit consists of an alnico material.
Claim 4
Dependent Claim
31 words
A stator of a direct-current machine according to claim 1, in which a recess is provided in each of said inner magnet units at the opposing end thereof to the armature.
Claim 5
Dependent Claim
31 words
A stator of a direct-current machine according to claim 2, in which a recess is provided in each of said inner magnet units at the opposing end thereof to the armature.
Claim 6
Dependent Claim
35 words
A stator of a direct-current machine according to claim 1, in which each of said magnet units is magnetized in the circumferencial direction and forming a fan-shaped section in the space between said magnetic poles.
Claim 7
Dependent Claim
39 words
A stator of a direct-current machine according to claim 1, in which each of said magnets is composed of said at least two magnet units so as to form a polygonal section in the space between said magnetic poles.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-16 | 1978-03-18 | 1978-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-16 | 1982-03-18 | 1982-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-16 | 1986-03-18 | 1986-09-17 | $7700.00 | Window Closed / Lapsed |