Patent US3898543A successfully refreshed from Google Patents.
US3898543A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric motors
Assignee: National Research Development Corp UK
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Filing: 1974-01-31
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Granted: 1975-08-05
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Expires: 1994-01-31
Abstract
Abstract A 3-phase, alternating current, speed-changing electric motor, or generator, suitable for 6-terminal, series/parallel switching and with pole-changing effected by pole-amplitude modulation, having a composite 3-phase stator winding comprising two component windings; the two component windings I. HAVING CORRESPONDING COMPONENT PHASE-WINDINGS CONNECTED IN THE SAME PHASE OF THE COMPOSITE WINDING, II. BEING COMPOSED OF IDENTICAL HALVES OF A POLE-AMPLITUDE MODULATION WINDING PROVIDING THE REQUIRED OPERATING POLENUMBERS AND III. PROVIDING EQUAL, PARALLEL CIRCUITS FOR ONE POLE-NUMBER.
Inventors
- 👤 Alexander Richard Wil Broadway
- 👤 William Fong
- 👤 Gordon Hindle Rawcliffe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:29
CPC Classifications
H; H02; H02K; H02K3/00; H02K3/04; H02K3/28; H02K17/00; H02K17/02; H02K17/12; H02K17/14
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
137 words
A three-phase, alternating-current, speedchanging electric machine, comprising a motor or generator, in which pole-changing is effected by the method of pole-amplitude modulation, having a composite three-phase stator winding comprising two component windings, said two component windings having their corresponding phase-windings arranged both in the same phase of the resultant said composite winding, each said component winding comprising two identical halves of a pole-amplitude modulation winding providing the operating pole-numbers required for the said speedchanging machine by even-cycle pole-amplitude modulation, the two said half-windings being spaced apart from each other around the composite stator winding periphery by a spacing other than a single-slot spacing and being connected together for one said pole-number to provide equal parallel circuits, in which polechanging is effected by alternate series/parallel connection of phase-winding parts of the said composite winding by sixterminal, terminal means.
Claim 2
Dependent Claim
137 words
A three-phase, alternating-current, speedchanging electric machine, comprising a motor or generator, in which pole-changing is effected by the method of pole-amplitude modulation, having a composite three-phase stator winding comprising two component windings, said two component windings having their corresponding phase-windings arranged both in the same phase of the resultant said composite winding, each said component winding comprising two identical halves of a pole-amplitude modulation winding providing the operating pole-numbers required for the said speedchanging machine by even-cycle pole-amplitude modulation, the two said half-windings being spaced apart from each other around the composite stator winding periphery by a spacing other than a single-slot spacing and being connected together for one said pole-number to provide equal parallel circuits, in which polechanging is effected by alternate series/parallel connection of phase-winding parts of the said composite winding by sixterminal, terminal means.
Claim 3
Dependent Claim
90 words
A speed-changing electric machine as claimed in claim 1, in which the said composite three-phase stator winding is wound on a slotted stator frame and the said two half-windings are spaced apart from each other around the stator frame periphery in such manner that corresponding parts of the two half-windings are spaced apart by a uniform number of slots, said number of slots corresponding to substantially an even number of poles for one said operating pole-number and substantially an odd number of poles for the other said operating pole number.
Claim 4
Dependent Claim
41 words
A speed-changing electric machine as claimed in claim 1, including switch means for connecting the two said half-windings in the said parallel connection for the said one pole-number and for connecting the two said half-windings serially together for the other pole-number.
Claim 5
Dependent Claim
41 words
A speed-changing electric machine as claimed in claim 2, having operating pole-numbers of 10-poles and 14-poles, in whicH the said composite winding is wound on a 48-slot stator and in which the two said half-windings are spaced apart by 10 slots.
Claim 6
Dependent Claim
63 words
A speed-changing electric machine as claimed in claim 4, in which a number of coils of one said half-winding corresponding to the slot-spacing, that is 10 coils, are transposed on the said stator frame by the number of slots corresponding to the remaining number of coils of the said half-winding, that is 14 slots and the current-carrying sense of the coils is reversed.
References Cited (Backward Citations)
US3299337A
Cited
US3673477A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-08-04 | 1979-02-03 | 1979-08-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-04 | 1983-02-03 | 1983-08-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-04 | 1987-02-03 | 1987-08-05 | $7700.00 | Window Closed / Lapsed |