US3790834A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low speed synchronous motor
Assignee: Individual
•
Filing: 1971-11-11
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Granted: 1974-02-05
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Expires: 1991-11-11
Abstract
Abstract A plurality of stationary poles, each comprising a pair of subpoles, are disposed in opposite relationship with a plurality of rotor magnet poles. The ratio of the number of stationary poles to the number of rotor magnet poles is chosen to be 2:3, 2:5 or 3:5 alternatively. A rotating magnetic field is produced in the array of stationary poles, and for every pi /2 interval of the period thereof, the rotor maintains a stabilized position in which there exists at least one set of a stationary sub-pole and a rotor pole of opposite polarities and attracted to each other. Also in this position, there exist an even number of sets of one sub-pole of a stationary pole and a rotor pole which are of like polarity, are displaced in angular position from each other and repel each other, these different sets producing a balance between their rotating efforts acting upon the rotor.
Inventors
- 👤 T Tanaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 09:55
CPC Classifications
G; G04; G04C; G04C15/00; H; H02; H02K; H02K21/00; H02K21/12; H02K21/125; H02K21/22; H02K21/227; H02K2201/00; H02K2201/12
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
184 words
A low speed synchronous motor including a rotor formed with a plurality of magnet poles thereon equi-angularly spaced apart with respect to a rotary shaft, and a stator having a plurality of stationary poles disposed in opposing relationship with the magnet poles on the rotor and equi-angularly spaced apart with respect to the rotary shaft, each of said stationary poles consisting of a pair of sub-poles spaced apart in the direction of rotation of the rotor, said stator being adapted to produce a rotating field across the array of the stationary poles; said motor being characterized in that the pitch of the rotor poles is different from the pitch of the stationary poles, and that in a stabilized position of the rotor, there exists at least one set of angularly coincident and attracting stator sub-poles and rotor poles of opposite polarities and there exist an even number of sets of repelling stator sub-poles and rotor poles of like polarity which are angularly closely displaced from each other, said even number of repelling sets producing respective rotating efforts on the rotor which cancel each other.
Claim 2
Dependent Claim
184 words
A low speed synchronous motor including a rotor formed with a plurality of magnet poles thereon equi-angularly spaced apart with respect to a rotary shaft, and a stator having a plurality of stationary poles disposed in opposing relationship with the magnet poles on the rotor and equi-angularly spaced apart with respect to the rotary shaft, each of said stationary poles consisting of a pair of sub-poles spaced apart in the direction of rotation of the rotor, said stator being adapted to produce a rotating field across the array of the stationary poles; said motor being characterized in that the pitch of the rotor poles is different from the pitch of the stationary poles, and that in a stabilized position of the rotor, there exists at least one set of angularly coincident and attracting stator sub-poles and rotor poles of opposite polarities and there exist an even number of sets of repelling stator sub-poles and rotor poles of like polarity which are angularly closely displaced from each other, said even number of repelling sets producing respective rotating efforts on the rotor which cancel each other.
Claim 3
Dependent Claim
30 words
A low speed synchronous motor according to claim 1, in which the ratio of the number of stationary poles to the number of rotor poles is chosen to be 2:3.
Claim 4
Dependent Claim
42 words
A low speed synchronous motor according to claim 1, in which the ratio of the number of stationary poles to the number of rotor poles is chosen to be 2:6, and the rotor poles comprises an array of alternating N- and S-poles.
Claim 5
Dependent Claim
30 words
A low speed synchronous motor according to claim 1, in which the ratio of the number of stationary poles to the number of rotor poles is chosen to be 2:5.
Claim 6
Dependent Claim
42 words
A low speed synchronous motor according to claim 1, in which the ratio of the number of stationary poles to the number of rotor poles is chosen to be 2:10, and the rotor poles comprises an array of alternating N- and S-poles.
Claim 7
Dependent Claim
42 words
A low speed synchronous motor according to claim 1, in which the ratio of the number of stationary poles to the number of rotor poles is chosen to be 3:5, and the rotor poles comprises an array of alternating N- and S-poles.
Claim 8
Dependent Claim
64 words
A low speed synchronous motor according to claim 1, in which one-half of the rotor is formed with a plurality of S-poles and the other half of the rotor is formed with a plurality of N-poles, the both N- and S-poles having a common pitch and are displaced from each other by the sum of an integral multiple of the pitch an one-half pitch.
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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 |