Patent US4841977A successfully refreshed from Google Patents.
Patent US3790833A successfully refreshed from Google Patents.
US3790833A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Synchronous motor
Assignee: Nidec Precision Corp
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Filing: 1973-05-24
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Granted: 1974-02-05
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Expires: 1993-05-24
Abstract
Abstract A non-self-starting type synchronous motor comprises a pair of permanent-magnet rotors rotatable in directions opposite to each other by means of magnetic coupling in order to prevent the rotational motion of the rotators from being stopped by step-out of the synchronous motion because of vibration or impact and also a field coil for giving a turning force to said pair of rotors.
Inventors
- 👤 S Hasebe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:22
CPC Classifications
H; H02; H02K; H02K7/00; H02K7/10; H02K7/118; H02K1/00; H02K1/06; H02K1/12; H02K16/00; H02K16/02; H02K7/11
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
83 words
A non-self-starting type synchronous motor comprising a first permanent-magnet rotor having a plural number of magnetic poles, a field coil arranged adjacent to said first permanent-magnet rotor embracing a part of said first permanent-magnet rotor, and a second permanent-magnet rotor having the same number of magnetic poles as said first permanent-magnet rotor and arranged adjacent to said first permanent-magnet rotor so that said second permanent-magnet rotor rotates in direction opposite to said first permanent-magnet rotor being magnetically coupled with said first permanent-magnet rotor.
Claim 2
Dependent Claim
83 words
A non-self-starting type synchronous motor comprising a first permanent-magnet rotor having a plural number of magnetic poles, a field coil arranged adjacent to said first permanent-magnet rotor embracing a part of said first permanent-magnet rotor, and a second permanent-magnet rotor having the same number of magnetic poles as said first permanent-magnet rotor and arranged adjacent to said first permanent-magnet rotor so that said second permanent-magnet rotor rotates in direction opposite to said first permanent-magnet rotor being magnetically coupled with said first permanent-magnet rotor.
Claim 3
Dependent Claim
30 words
A non-self-starting type synchronous motor according to the claim 1 further comprising a field coil arranged adjacent to said second permanent-magnet rotor embracing a part of said second permanent-magnet rotor.
Claim 4
Dependent Claim
87 words
A non-self-starting type synchronous motor comprising a first permanent-magnet rotor having a plural number of magnetic poles, a second permanent-magnet rotor having the same number of magnetic poles as said first permanent-magnet rotor and arranged adjacent to said first permanent-magnet rotor so that said second permanent-magnet rotor rotates in direction opposite to said first permanent-magnet rotor being magnetically coupled with said first permanent-magnet rotor, and a field coil arranged between said first and second permanent-magnet rotors embracing a part of said first and second permanent-magnet rotors respectively.
Claim 5
Dependent Claim
87 words
A non-self-starting type synchronous motor comprising a first permanent-magnet rotor having a plural number of magnetic poles, a second permanent-magnet rotor having the same number of magnetic poles as said first permanent-magnet rotor and arranged adjacent to said first permanent-magnet rotor so that said second permanent-magnet rotor rotates in direction opposite to said first permanent-magnet rotor being magnetically coupled with said first permanent-magnet rotor, and a field coil arranged between said first and second permanent-magnet rotors embracing a part of said first and second permanent-magnet rotors respectively.
References Cited (Backward Citations)
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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) | 1977-02-04 | 1977-08-06 | 1978-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-04 | 1981-08-06 | 1982-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-04 | 1985-08-06 | 1986-02-05 | $7700.00 | Window Closed / Lapsed |