Patent US3657583A successfully refreshed from Google Patents.
US3657583A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Miniature synchronous motors
Assignee: Tohoku Oki Electric Co Ltd
•
Filing: 1970-11-12
•
Granted: 1972-04-18
•
Expires: 1990-11-12
Abstract
Abstract A miniature synchronous motor having a pot shaped core of high permeability magnetic material and having a central leg and an annular periphery, an energizing coil wound upon the central leg, a circular disc rotor rotatably journalled on the central leg, and an annular stator disposed on the annular periphery to closely surround the rotor.
Inventors
- 👤 Naokichi Tamaru
- 👤 Shunsaku Nakauchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:18
CPC Classifications
H; H02; H02K; H02K21/00; H02K21/12; H02K21/125; H02K1/00; H02K1/06; H02K1/12; H02K19/00; H02K19/02; H02K19/04; H02K19/06; H02K2201/00; H02K2201/12
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
94 words
A miniature synchronous motor comprising a pot shaped core of high permeability magnetic material, said core having a central leg and an annular periphery, an energizing coil wound upon said central leg, a magnetic rotor in the form of a complete circular disc with a plurality of peripheral poles thereon rotatably journalled on the axis of said central leg, and an annular magnetic stator disposed on said annular periphery to closely surround said rotor said stator being a complete circle and having a corresponding number of inner poles opposing said poles on said rotor.
Claim 2
Dependent Claim
94 words
A miniature synchronous motor comprising a pot shaped core of high permeability magnetic material, said core having a central leg and an annular periphery, an energizing coil wound upon said central leg, a magnetic rotor in the form of a complete circular disc with a plurality of peripheral poles thereon rotatably journalled on the axis of said central leg, and an annular magnetic stator disposed on said annular periphery to closely surround said rotor said stator being a complete circle and having a corresponding number of inner poles opposing said poles on said rotor.
Claim 3
Dependent Claim
17 words
The miniature synchronous motor according to claim 1 wherein said pot shaped core is made of ferrite.
Claim 4
Dependent Claim
17 words
The miniature synchronous motor according to claim 1 wherein said stator and rotor are made of Permalloy.
Claim 5
Dependent Claim
37 words
The miniature synchronous motor according to claim 1 which further comprises a permanent magnet disposed coaxially with said rotor to produce a unidirectional biasing flux superposed on the flux produced by said energizing coil in said rotor.
Claim 6
Dependent Claim
37 words
The miniature synchronous motor according to claim 4 wherein the magnitude of the unidirectional biasing flux of the permanent magnet is made substantially equal to the crest value of the AC flux produced by the energizing coil.
References Cited (Backward Citations)
US1708334A
Cited
US2110967A
Cited
US2103356A
Cited
US2424020A
Cited
US2885645A
Cited
US3356876A
Cited
US3148319A
Cited
US3333128A
Cited
US3475630A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-18 | 1975-10-18 | 1976-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-18 | 1979-10-18 | 1980-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-18 | 1983-10-18 | 1984-04-18 | $7700.00 | Window Closed / Lapsed |