US3863084A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Synchronous motor
Assignee: Nidec Precision Corp
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Filing: 1973-11-29
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Granted: 1975-01-28
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Expires: 1993-11-29
Abstract
Abstract A self-starting type synchronous motor comprising a pair of permanent-magnet rotors rotatable in directions opposite to each other by means of magnetic coupling, and a magnetic pole arranged adjacent to at least one of said rotors and capable of making said rotors rest at positions shifted from such positions where the magnetic coupling is strongest, for the purpose of achieving reliable self-starting.
Inventors
- 👤 Sukehiro Hasebe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:21
CPC Classifications
H; H02; H02K; H02K1/00; H02K1/06; H02K1/12
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
129 words
A synchronous motor comprising a permanent-magnet rotor having a plural number of magnetic poles, a second permanentmagnet 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 a direction opposite to said first permanent-magnet rotor and being magnetically coupled with said first permanentmagnet rotor, at least one coreless field coil arranged to embrace a part of at least one of said first and second permanent-magnet rotors, and a magnetic pole piece arranged adjacent to at least one of said first and second permanentmagnet rotors in order to rest said first and second permanentmagnet rotors at positions shifted by a predetermined rotation angle other than 45* from their inherent rest positions.
Claim 2
Dependent Claim
129 words
A synchronous motor comprising a permanent-magnet rotor having a plural number of magnetic poles, a second permanentmagnet 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 a direction opposite to said first permanent-magnet rotor and being magnetically coupled with said first permanentmagnet rotor, at least one coreless field coil arranged to embrace a part of at least one of said first and second permanent-magnet rotors, and a magnetic pole piece arranged adjacent to at least one of said first and second permanentmagnet rotors in order to rest said first and second permanentmagnet rotors at positions shifted by a predetermined rotation angle other than 45* from their inherent rest positions.
Claim 3
Dependent Claim
16 words
A synchronous motor according to the claim 1, in which said magnetic pole piece is movable.
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) | 1978-01-27 | 1978-07-29 | 1979-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-27 | 1982-07-29 | 1983-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-27 | 1986-07-29 | 1987-01-28 | $7700.00 | Window Closed / Lapsed |