US3875437A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable reluctance type step motor
Assignee: Hitachi Ltd
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Filing: 1973-12-26
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Granted: 1975-04-01
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Expires: 1993-12-26
Abstract
Abstract A variable reluctance type step motor is disclosed which comprises a rotor core having teeth, a stator core having a plurality of magnetic poles arranged thereon opposing to the teeth of the rotor core, each of the magnetic poles being wound with an exciting winding and being provided with stator teeth on the surface thereof opposing to the rotor teeth in the number in a predetermined relationship with the number of the rotor teeth, wherein the stator teeth are pulse excited in a predetermined phase sequence thereby to change the relative position of the stator teeth to the rotor teeth by a predetermined amount, so that each time of application of a pulse to the exciting windings, the rotor is rotated by one step in the direction determined by the sequence of excitation.
Inventors
- 👤 Hiroshi Hara
- 👤 Kazuo Onishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:52
CPC Classifications
H; H02; H02K; H02K37/00; H02K37/02; H02K37/04
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
145 words
A step motor of variable reluctance type comprising a stator core, a plurality of magnetic poles wound with a plurality of excitation windings, a rotor core mounted on a rotary shaft, a plurality of rotor teeth equidistantly formed along the outer periphery of said rotor core and a plurality of stator teeth formed along the inner periphery of said magnetic poles; wherein the phase arrangement of the magnetic poles of the stator core satisfies the equation P(mn + OR - (2)k) Nr where m is the number of phases of the excitation windings, P the number of poles for each phse, Nr the number of rotor teeth, n a given integral number, and k is an integral number greater than one, and further the order of phase arrangement of the magnEtic poles of the stator core is determined by the value and sign of k.
Claim 2
Dependent Claim
145 words
A step motor of variable reluctance type comprising a stator core, a plurality of magnetic poles wound with a plurality of excitation windings, a rotor core mounted on a rotary shaft, a plurality of rotor teeth equidistantly formed along the outer periphery of said rotor core and a plurality of stator teeth formed along the inner periphery of said magnetic poles; wherein the phase arrangement of the magnetic poles of the stator core satisfies the equation P(mn + OR - (2)k) Nr where m is the number of phases of the excitation windings, P the number of poles for each phse, Nr the number of rotor teeth, n a given integral number, and k is an integral number greater than one, and further the order of phase arrangement of the magnEtic poles of the stator core is determined by the value and sign of k.
Claim 3
Dependent Claim
15 words
A step motor of variable reluctance type according to claim 1, wherein k is 2.
Claim 4
Dependent Claim
168 words
A step motor of variable reluctance type comprising a stator core, a plurality of magnetic poles wound with a plurality of excitation windings, a rotor core mounted on a rotary shaft, a plurality of rotor teeth equidistantly formed along the outer periphery of said rotor core and a plurality of stator teeth formed along the inner periphery of said magnetic poles, wherein the phase arrangement and the number of stator teeth satisfy the equation P(mn + or - k) Nr wherein m is the number of phases of the excitation windings and is five-phase windings, P the number of poles for each phase, Nr the number of rotor teeth, n a predetermined integral number, and k is the integral number 2, the order and phase arrangement of the magnetic poles of the stator core being determined by the value and the sign of k, and the order of the phase arrangement of the five-phase excitation winding being different than the order and phase arrangement of the magnetic poles.
Claim 5
Dependent Claim
168 words
A step motor of variable reluctance type comprising a stator core, a plurality of magnetic poles wound with a plurality of excitation windings, a rotor core mounted on a rotary shaft, a plurality of rotor teeth equidistantly formed along the outer periphery of said rotor core and a plurality of stator teeth formed along the inner periphery of said magnetic poles, wherein the phase arrangement and the number of stator teeth satisfy the equation P(mn + or - k) Nr wherein m is the number of phases of the excitation windings and is five-phase windings, P the number of poles for each phase, Nr the number of rotor teeth, n a predetermined integral number, and k is the integral number 2, the order and phase arrangement of the magnetic poles of the stator core being determined by the value and the sign of k, and the order of the phase arrangement of the five-phase excitation winding being different than the order and phase arrangement of the magnetic poles.
Claim 6
Dependent Claim
111 words
A step motor of variable reluctance type according to claim 3, wherein said motor comprises five-phase magnetic poles A, B, C, D and E adapted to be respectively excited by five-phase excitation windings, so that when the magnetic pole A is excited and the center line thereof coincides with that of corresponding rotor teeth thereto, each of the center lines of the magnetic poles B and E is out of alignment from those of corresponding rotor teeth thereto by 1/5Tr, and each of the center lines of the magnetic poles C and D is displaced from those of corresponding rotor teeth by 2/5Tr, Tr being the tooth pitch of the rotor.
Claim 7
Dependent Claim
41 words
A step motor of variable reluctance type according to claim 3, wherein the sign of k is + and five-phase magnetic poles A, B, C, D and E are provided, said magnetic poles having an order and phase arrangement of ADBEC.
Claim 8
Dependent Claim
23 words
A step motor of variable reluctance type according to claim 5, wherein said excitation windings are arranged for excitation in the order ABCDE.
Claim 9
Dependent Claim
41 words
A step motor of variable reluctance type according to claim 3, wherein the sign of k is - and five-phase magnetic poles A, B, C, D and E are provided, said magnetic poles having an order and phase arrangement of ACEBD.
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) | 1978-03-31 | 1978-09-30 | 1979-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-31 | 1982-09-30 | 1983-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-31 | 1986-09-30 | 1987-04-01 | $7700.00 | Window Closed / Lapsed |