US5886445A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Extended cage adjustable speed electric motors and drive packages
Assignee: LOCKHEEDMARTIN ENERGY RESEARCH Corp
•
Filing: 1997-07-02
•
Granted: 1999-03-23
•
Expires: 2017-07-02
Abstract
Abstract The rotor cage of a motor is extended, a second stator is coupled to this extended rotor cage, and the windings have the same number of poles. The motor torque and speed can be controlled by either injecting energy into or extracting energy out from the rotor cage. The motor produces less harmonics than existing doubly-fed motors. Consequently, a new type of low cost, high efficiency drive is produced.
Inventors
- 👤 John S. Hsu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 06:03
CPC Classifications
H; H02; H02K; H02K16/00; H02K17/00; H02K17/02; H02K17/16
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
112 words
In an electric motor, an improvement comprising: a first stator assembly; a second stator assembly asymmetrical to and not magnetically coupled to said first stator assembly; and an extended cage rotor having correspondingly asymmetrical first and second rotor sections arranged along nontransposed extended cage bars, said first rotor section magnetically coupled to said first stator assembly, and said second rotor section magnetically coupled to said second stator assembly; either or both of said first or second stator assemblies including a stator lamination stack, a toroidal winding disposed around said stator lamination stack, and a magnetic flux leakage shield made of nonmagnetic metal disposed between said stator lamination stack and said toroidal winding.
Claim 2
Dependent Claim
112 words
In an electric motor, an improvement comprising: a first stator assembly; a second stator assembly asymmetrical to and not magnetically coupled to said first stator assembly; and an extended cage rotor having correspondingly asymmetrical first and second rotor sections arranged along nontransposed extended cage bars, said first rotor section magnetically coupled to said first stator assembly, and said second rotor section magnetically coupled to said second stator assembly; either or both of said first or second stator assemblies including a stator lamination stack, a toroidal winding disposed around said stator lamination stack, and a magnetic flux leakage shield made of nonmagnetic metal disposed between said stator lamination stack and said toroidal winding.
Claim 3
Dependent Claim
20 words
The motor of claim 1 further including a control system for controlling the motor speed, startup current and running current.
Claim 4
Dependent Claim
24 words
The motor of claim 2 wherein said control system comprises a power electronic control circuit to provide smooth speed control and bidirectional power flow.
Claim 5
Dependent Claim
20 words
The motor of claim 2 wherein said control system comprises arranging one of said stator windings in open circuit configuration.
Claim 6
Dependent Claim
20 words
The motor of claim 2 wherein said control system comprises connecting one of said stator windings in short circuit configuration.
Claim 7
Dependent Claim
21 words
The motor of claim 2 wherein said control system comprises connecting one of said stator windings to a bank of resistors.
Claim 8
Dependent Claim
13 words
The motor of claim 1 wherein said motor is a radial gap motor.
Claim 9
Dependent Claim
13 words
The motor of claim 1 wherein said motor is an axial gap motor.
Claim 10
Dependent Claim
12 words
The motor of claim 8 wherein said motor is a three-phase motor.
Claim 11
Dependent Claim
12 words
The motor of claim 8 wherein said motor is a single-phase motor.
Claim 12
Dependent Claim
14 words
The motor of claim 8 wherein said motor is a multiple speed winding motor.
Claim 13
Dependent Claim
107 words
In an axial gap extended cage electric motor including a rotor, two rotor end rings, and a rotor hub, an improvement comprising: a first stator assembly; a second stator assembly asymmetrical to and not magnetically coupled to said first stator assembly; and an extended cage rotor having correspondingly asymmetrical first and second rotor sections arranged along nontransposed j-shaped extended cage bars, said first rotor section magnetically coupled to said first stator assembly, said second rotor section magnetically coupled to said second stator assembly, said extended cage bars affixed between the two rotor end rings such that one of said end rings is affixed to said rotor hub.
Claim 14
Dependent Claim
107 words
In an axial gap extended cage electric motor including a rotor, two rotor end rings, and a rotor hub, an improvement comprising: a first stator assembly; a second stator assembly asymmetrical to and not magnetically coupled to said first stator assembly; and an extended cage rotor having correspondingly asymmetrical first and second rotor sections arranged along nontransposed j-shaped extended cage bars, said first rotor section magnetically coupled to said first stator assembly, said second rotor section magnetically coupled to said second stator assembly, said extended cage bars affixed between the two rotor end rings such that one of said end rings is affixed to said rotor hub.
Claim 15
Dependent Claim
12 words
The motor of claim 12 wherein said motor is a three-phase motor.
Claim 16
Dependent Claim
12 words
The motor of claim 12 wherein said motor is a single-phase motor.
Claim 17
Dependent Claim
14 words
The motor of claim 12 wherein said motor is a multiple speed winding motor.
Claim 18
Dependent Claim
20 words
The motor of claim 12 further including a control system for controlling the motor speed, startup current and running current.
Claim 19
Dependent Claim
24 words
The motor of claim 16 wherein said control system comprises a power electronic control circuit to provide smooth speed control and bidirectional power flow.
Claim 20
Dependent Claim
20 words
The motor of claim 16 wherein said control system comprises arranging one of said stator windings in open circuit configuration.
Claim 21
Dependent Claim
20 words
The motor of claim 16 wherein said control system comprises connecting one of said stator windings in short circuit configuration.
Claim 22
Dependent Claim
21 words
The motor of claim 16 wherein said control system comprises connecting one of said stator windings to a bank of resistors.
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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) | 2002-03-22 | 2002-09-21 | 2003-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-03-22 | 2006-09-21 | 2007-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-03-22 | 2010-09-21 | 2011-03-23 | $7700.00 | Window Closed / Lapsed |