Patent US4145645A successfully refreshed from Google Patents.
US4145645A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Speed control means for squirrel-cage motor
Assignee: Harnischfeger Corp
•
Filing: 1976-10-13
•
Granted: 1979-03-20
•
Expires: 1996-10-13
Abstract
Abstract There is disclosed a squirrel-cage motor for a winch drive or other application and control means for operating the motor in hoist or lower directions at any one of a plurality of speeds in either direction. The motor and winch are provided with a load brake. In one embodiment, the stator comprises two stator windings having different numbers of poles to provide high speed (fewer poles) and low speed (more poles) windings. The control means comprises a direct current power source, an alternating current power source, means for connecting the sources to the stator windings so that different speed points and braking operations are achieved, and means for operating the load brake. Low speed results from simultaneously energizing the low speed winding and the high speed winding from the alternating current power source and the direct current power source, respectively. Intermediate speed results from energizing only the low speed winding from the alternating current power source. High speed results from energizing only the high speed winding from the alternating current power source. The control means includes time delay means to prevent connection of the alternating current source to the winding previously energized from the direct current source until arcing across a direct current contactor in the control means ceases during transition from low speed to higher speed.
Inventors
- 👤 Lester A. Price
- 👤 Gerold E. Schmid
- 👤 Lawrence A. Millonzi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:22
CPC Classifications
B; B66; B66C; B66C13/00; B66C13/18; B66C13/22; B66C13/23; B66C13/26; H; H02; H02P; H02P23/00; H02P23/10; H02P25/00; H02P25/16; H02P25/18; H02P25/20
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
224 words
In combination: an electric motor comprising a rotor and a stator, said stator comprising at least two stator windings, with one stator winding having a greater number of poles than the other stator winding; an alternating current source; a direct current source; and control means for operating said rotor at any one of a multiplicity of different speeds, said control means comprising: means for energizing said one stator winding from said alternating current source and simultaneously energizing said other stator winding from said direct current source to effect operation of said rotor at a given speed; means for deenergizing said other stator winding from said direct current source and for energizing said one stator winding from said alternating current source to effect operation of said rotor at an intermediate speed greater than said given speed; means for deenergizing said one stator winding from said alternating current source and for energizing another stator winding other than said one stator winding from said alternating current source to effect operation of said rotor at a speed greater than said intermediate speed; and first time delay means to prevent application of alternating current from said alternating current source to any winding previously energized from said direct current source until arcing ceases between said direct current source and said any winding during transition from one rotor speed to another.
Claim 2
Dependent Claim
224 words
In combination: an electric motor comprising a rotor and a stator, said stator comprising at least two stator windings, with one stator winding having a greater number of poles than the other stator winding; an alternating current source; a direct current source; and control means for operating said rotor at any one of a multiplicity of different speeds, said control means comprising: means for energizing said one stator winding from said alternating current source and simultaneously energizing said other stator winding from said direct current source to effect operation of said rotor at a given speed; means for deenergizing said other stator winding from said direct current source and for energizing said one stator winding from said alternating current source to effect operation of said rotor at an intermediate speed greater than said given speed; means for deenergizing said one stator winding from said alternating current source and for energizing another stator winding other than said one stator winding from said alternating current source to effect operation of said rotor at a speed greater than said intermediate speed; and first time delay means to prevent application of alternating current from said alternating current source to any winding previously energized from said direct current source until arcing ceases between said direct current source and said any winding during transition from one rotor speed to another.
Claim 3
Dependent Claim
41 words
A combination according to claim 1 wherein said control means comprises means to momentarily apply direct current from said direct current source to a stator winding during transition from one rotor speed to a lower rotor speed to effect dynamic braking.
Claim 4
Dependent Claim
41 words
A combination according to claim 1 wherein said control means comprises means to momentarily apply alternating current from said alternating current source to a stator winding during transition from one rotor speed to a lower rotor speed to effect regenerative braking.
Claim 5
Dependent Claim
292 words
In combination: an electric motor comprising a rotor and a stator defining at least two magnetic circuits, one magnetic circuit comprising at least one low speed stator winding, the other magnetic circuit comprising a low speed stator winding and a high speed stator winding, with said low speed stator winding in said one magnetic circuit having a greater number of poles than either stator winding in said other magnetic circuit; an alternating current source; a direct current source; and control means for operating said rotor at any one of a multiplicity of different speeds, said control means comprising: means for energizing one of said low speed stator windings from said alternating current source while the other of said low speed windings is de-energized and simultaneously energizing said high speed stator winding in said other magnetic circuit from said direct current source to effect operation of said rotor at a given speed; means for deenergizing said high speed stator winding in said other magnetic circuit from said direct current source and for energizing said one low speed stator winding from said alternating current source to effect operation of said rotor at an intermediate speed greater than said given speed; means for deenergizing said one low speed stator winding from said alternating current source and for energizing either of said stator windings in said other magnetic circuit from said alternating current source to effect operation of said rotor at a speed greater than said intermediate speed; and first time delay means to prevent application of alternating current from said alternating current source to any winding previously energized from said direct current source until arcing ceases between said direct current source and said any winding during transition from one rotor speed to another rotor speed.
Claim 6
Dependent Claim
292 words
In combination: an electric motor comprising a rotor and a stator defining at least two magnetic circuits, one magnetic circuit comprising at least one low speed stator winding, the other magnetic circuit comprising a low speed stator winding and a high speed stator winding, with said low speed stator winding in said one magnetic circuit having a greater number of poles than either stator winding in said other magnetic circuit; an alternating current source; a direct current source; and control means for operating said rotor at any one of a multiplicity of different speeds, said control means comprising: means for energizing one of said low speed stator windings from said alternating current source while the other of said low speed windings is de-energized and simultaneously energizing said high speed stator winding in said other magnetic circuit from said direct current source to effect operation of said rotor at a given speed; means for deenergizing said high speed stator winding in said other magnetic circuit from said direct current source and for energizing said one low speed stator winding from said alternating current source to effect operation of said rotor at an intermediate speed greater than said given speed; means for deenergizing said one low speed stator winding from said alternating current source and for energizing either of said stator windings in said other magnetic circuit from said alternating current source to effect operation of said rotor at a speed greater than said intermediate speed; and first time delay means to prevent application of alternating current from said alternating current source to any winding previously energized from said direct current source until arcing ceases between said direct current source and said any winding during transition from one rotor speed to another rotor speed.
Claim 7
Dependent Claim
43 words
A combination according to claim 4 wherein said control means comprises means to momentarily apply direct current from said direct current source to said high speed stator winding during transition from one rotor speed to a lower rotor speed to effect dynamic braking.
Claim 8
Dependent Claim
44 words
A combination according to claim 4 wherein said control means comprises means to momentarily apply alternating current from said alternating current source to said one low speed stator winding during transition from one rotor speed to a lower rotor speed to effect regenerative braking.
Claim 9
Dependent Claim
354 words
In combination: an electric motor comprising a rotor and a stator defining at least two magnetic circuits, one magnetic circuit comprising at least one low speed stator winding, the other magnetic circuit comprising a low speed stator winding and a high speed stator winding, with said low speed stator winding in said one magnetic circuit having a greater number of poles than either stator winding in said other magnetic circuit; an alternating current source; a direct current source; and control means for operating said rotor at any one of a multiplicity of different speeds, said control means comprising: means for energizing said low speed stator winding in said one magnetic circuit from said alternating current source while the other of said low speed windings is de-energized and simultaneously energizing said high speed stator winding in said other magnetic circuit from said direct current source to effect operation of said rotor at a given speed; means for deenergizing said high speed stator winding in said other magnetic circuit from said direct current source and for energizing said low speed stator winding in said one magnetic circuit from said alternating current source to effect operation of said rotor at an intermediate speed greater than said given speed; means for deenergizing said low speed stator winding in said one magnetic circuit from said alternating current source and for energizing said low speed stator winding in said other magnetic circuit from said alternating current source to effect operation of said rotor at a first speed greater than said intermediate speed; means for deenergizing said low speed winding in said other magnetic circuit from said alternating current source and for energizing said high speed stator winding in said other magnetic circuit from said alternating current source to effect operation of said rotor at a second speed greater than said first speed; and first time delay means to prevent application of alternating current from said alternating current source to any winding previously energized from said direct current source until arcing ceases between said direct current source and said any winding during transition from one rotor speed to another rotor speed.
Claim 10
Dependent Claim
354 words
In combination: an electric motor comprising a rotor and a stator defining at least two magnetic circuits, one magnetic circuit comprising at least one low speed stator winding, the other magnetic circuit comprising a low speed stator winding and a high speed stator winding, with said low speed stator winding in said one magnetic circuit having a greater number of poles than either stator winding in said other magnetic circuit; an alternating current source; a direct current source; and control means for operating said rotor at any one of a multiplicity of different speeds, said control means comprising: means for energizing said low speed stator winding in said one magnetic circuit from said alternating current source while the other of said low speed windings is de-energized and simultaneously energizing said high speed stator winding in said other magnetic circuit from said direct current source to effect operation of said rotor at a given speed; means for deenergizing said high speed stator winding in said other magnetic circuit from said direct current source and for energizing said low speed stator winding in said one magnetic circuit from said alternating current source to effect operation of said rotor at an intermediate speed greater than said given speed; means for deenergizing said low speed stator winding in said one magnetic circuit from said alternating current source and for energizing said low speed stator winding in said other magnetic circuit from said alternating current source to effect operation of said rotor at a first speed greater than said intermediate speed; means for deenergizing said low speed winding in said other magnetic circuit from said alternating current source and for energizing said high speed stator winding in said other magnetic circuit from said alternating current source to effect operation of said rotor at a second speed greater than said first speed; and first time delay means to prevent application of alternating current from said alternating current source to any winding previously energized from said direct current source until arcing ceases between said direct current source and said any winding during transition from one rotor speed to another rotor speed.
Claim 11
Dependent Claim
48 words
A combination according to claim 7 wherein said control means comprises means to momentarily apply direct current from said direct current source to said high speed stator winding in said other magnetic circuit during transition from one rotor speed to a lower rotor speed to effect dynamic braking.
Claim 12
Dependent Claim
48 words
A combination according to claim 7 wherein said control means comprises means to momentarily apply alternating current from said alternating current source to said low speed stator winding in said one magnetic circuit during transition from one rotor speed to a lower rotor speed to effect regenerative braking.
References Cited (Backward Citations)
US2677087A
Cited
US2847630A
Cited
US2740932A
Cited
US2816258A
Cited
US2793339A
Cited
US2840772A
Cited
US3011594A
Cited
US3166701A
Cited
US3281633A
Cited
US3368073A
Cited
US3786327A
Cited
US3721832A
Cited
US3919600A
Cited
US3864611A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-03-19 | 1982-09-18 | 1983-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-19 | 1986-09-18 | 1987-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-19 | 1990-09-18 | 1991-03-20 | $7700.00 | Window Closed / Lapsed |