Patent US3780324A successfully refreshed from Google Patents.
US3780324A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Adjustable speed induction motor system
Assignee: Lear Motors Corp
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Filing: 1972-06-05
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Granted: 1973-12-18
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Expires: 1992-06-05
Abstract
Abstract An electric induction motor/control system providing the desirable high starting torque and wide speed characteristics of direct current motors. The stator of the induction motor has two specially interrelated winding sets per phase. The motor windings are supplied with unidirectional current pulses from silicon controlled rectifiers that are programmed to provide advantageous modes of operation for the motor. The unique relation and interaction between the motor windings hereof and the associated electronic circuitry results in high power factor, good efficiency, and self-clearing SCR commutation action. The preferred motors use a squirrel cage rotor with no commutator, brushes, or slip rings. The complementary stator winding arrangements are not voltage limited, and thereby permit the construction of large power motor systems. Practical motor ratings are from fractional to over 500 horsepower, at speeds ranging from 600 to 40,000 rpm, and higher. With selective control circuitry the motors hereof can be operated: (a) at constant output torque over a wide speed range; (b) at constant horsepower over a selected speed range; (c) with traction output characteristics similar to that of series motors; (d) at constant speed; (e) and with direct speed reversal in any of these modes. The motor systems require little maintenance, and may be hermetically sealed.
Inventors
- 👤 J Greenwell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:15
CPC Classifications
H; H02; H02K; H02K29/00; H02K29/03; H02K3/00; H02K3/04; H02K3/28; H02P; H02P23/00; H02P23/28
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
70 words
A polyphase motor system comprising a stator and an induction rotor, said stator containing a plurality of half-phase windings in paired consequent pole array with one pair for each effective phase for the motor when in polyphase operation, each of said windings being wound in full pitch across 180 magnetic degrees, the complementary windings of each said pair being alternated in position along the stator at substantially 180* magnetic separation.
Claim 2
Dependent Claim
70 words
A polyphase motor system comprising a stator and an induction rotor, said stator containing a plurality of half-phase windings in paired consequent pole array with one pair for each effective phase for the motor when in polyphase operation, each of said windings being wound in full pitch across 180 magnetic degrees, the complementary windings of each said pair being alternated in position along the stator at substantially 180* magnetic separation.
Claim 3
Dependent Claim
25 words
A polyphase motor system as claimed in claim 1, in which adjacent turns of said paired windings are located in common slots in the stator.
Claim 4
Dependent Claim
37 words
A polyphase motor system as claimed in claim 1, in which adjacent turns of said paired windings are located in common slots in the stator, and substantial phase insulation between the respective winding turns of said slots.
Claim 5
Dependent Claim
23 words
A polyphase motor system as claimed in claim 1, in which said half-phase windings are wound in the stator in substantially concentric form.
Claim 6
Dependent Claim
23 words
A polyphase motor system as claimed in claim 2, in which said half-phase windings are wound in the stator in substantially concentric form.
Claim 7
Dependent Claim
41 words
A polyphase motor system as claimed in claim 1, in which each of said half-phase windings provides a plurality of magnetic pole sets, all of said pole sets being symmetrically interrelated about the stator among said pairs and their phase positions.
Claim 8
Dependent Claim
40 words
A polyphase motor system as claimed in claim 1, in which said half-phase windings are arrayed about the stator with equal magnetic and physical separation between adjacent windings, each winding pair being fitted within the spaces along the related windings.
Claim 9
Dependent Claim
50 words
A polyphase motor system as claimed in claim 1, in which said half-phase windings are arrayed about the stator with equal magnetic and physical separtion between adjacent windings, associated windings of each pair being respectively interconnected into two symmetrical polyphase winding groups that are 180* apart magnetically in the stator.
Claim 10
Dependent Claim
31 words
A polyphase motor system as claimd in claim 1, in which said half-phase windings are arrayed in the stator with relatively low mutual magnetic induction between the windings of respective pairs.
Claim 11
Dependent Claim
31 words
A polyphase motor system as claimed in claim 2, in which said half-phase windings are arrayed in the stator with relatively low mutual magnetic induction between the windings of respective pairs.
Claim 12
Dependent Claim
153 words
A polyphase motor system for operation with a plurality of controlled rectifiers comprising a stator and an induction rotor, said stator containing a plurality of half-phase windings in paired consequent pole array with one pair for each effective phase for the motor when in polyphase operation, each of said windings being wound in full pitch across 180 magnetic degrees, the complementary windings of each said pair being alternated in position along the stator at substantially 180* magnetic separation, each of said half-phase windings being arranged for selective energization through an individual of said controlled rectifiers to provide a rotating magnetic field in the stator for corresponding operation of said induction rotor. 12. A polyphase motor system as claimed in claimed 11, in which each of said half-phase windings provides a plurality of magnetic pole sets, all of said pole sets being symmetrically interrelated about the stator among said pairs and their phase positions.
Claim 13
Dependent Claim
40 words
A polyphase motor system as claimed in claim 11, in which said half-phase windings are arrayed about the stator with equal magnetic and physical separation between adjacent windings, each winding pair being fitted within the spaces along the related windings.
Claim 14
Dependent Claim
50 words
A polyphase motor system as claimed in claim 11, in which said half-phase windings are arrayed about the stator with equal magnetic and physical separation between adjacent windings, associated windings of each pair being respectively interconnected into two symmetrical polyphase winding groups that are 180* apart magnetically in the stator.
Claim 15
Dependent Claim
31 words
A polyphase motor system as claimed in claim 11, in which said half-phase windings are arrayed in the stator with relatively low mutual maGnetic induction between the windings of respective pairs.
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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) | 1976-12-17 | 1977-06-18 | 1977-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-17 | 1981-06-18 | 1981-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-17 | 1985-06-18 | 1985-12-18 | $7700.00 | Window Closed / Lapsed |