US3611080A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Common load sharing by two or more synchronous motors
Assignee: General Electric Canada Co
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Filing: 1969-09-19
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Granted: 1971-10-05
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Expires: 1989-09-19
Abstract
Abstract A drive comprises at least two synchronous motors coupled for driving a load. Each of the motors has an armature winding for producing a rotating magnetic field when energized with alternating current, and a main field winding for producing a multipolar steady state magnetic field when energized with direct current. At least one of the motors also has an auxiliary field winding displaced with respect to the main winding. When energized with direct current the auxiliary winding produces a second multipolar steady state magnetic field having its polar axes displaced with respect to the polar axes of the main field. In one embodiment of the invention, axial slots centrally disposed within the pole piece heads serve to retain one side of two adjacent auxiliary field coils having a span of approximately one pole pitch while in a second embodiment of the invention, one side of the auxiliary field coils extend through a plurality of axial slots in the pole piece head with the other side of the coil being situated between the head and the main field coil disposed about the body of the pole piece. Load sharing is accomplished by varying the relative values of the direct current applied to said main and auxiliary windings of the one motor.
Inventors
- 👤 Gordon William Herzog
- 👤 Peter Duncan Fox-Thomas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:05
CPC Classifications
H; H02; H02P; H02P5/00; H02P5/74; H02P5/747
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
251 words
A synchronous motor for sharing a common load comprising stator and rotor magnetic cores, an armature winding disposed on one of said cores for producing a rotating magnetic field when energized with alternating current, a main field winding consisting of a number of main field coils disposed on the bodies of pole pieces on the other of said cores for producing a multipolar steady state magnetic field when energized with direct current, said multipolar field interacting with the alternating current generated magnetic field to rotate said motor, and an auxiliary field winding characterized by a number of auxiliary field coils electrically displaced with respect to said main coils to produce a second multipolar steady state magnetic field having polar axes located between the polar axes of said main field, said auxiliary field winding extending through at least one axial slot in the heads of said pole pieces above the pole bodies to assure a completely solidified pole body adjacent said main field windings, said slot containing one side of two adjacent auxiliary field coils having a span of approximately one pole pitch, a slit within said pole head communicating said one sides of the auxiliary field windings with the airgap between the stator and rotor magnetic cores, and means for varying the relative values of the direct current applied to said main and auxiliary windings of said motor whereby the polar axes of the resultant main and auxiliary windings can be shifted to alter the sharing of load by the motor.
Claim 2
Dependent Claim
251 words
A synchronous motor for sharing a common load comprising stator and rotor magnetic cores, an armature winding disposed on one of said cores for producing a rotating magnetic field when energized with alternating current, a main field winding consisting of a number of main field coils disposed on the bodies of pole pieces on the other of said cores for producing a multipolar steady state magnetic field when energized with direct current, said multipolar field interacting with the alternating current generated magnetic field to rotate said motor, and an auxiliary field winding characterized by a number of auxiliary field coils electrically displaced with respect to said main coils to produce a second multipolar steady state magnetic field having polar axes located between the polar axes of said main field, said auxiliary field winding extending through at least one axial slot in the heads of said pole pieces above the pole bodies to assure a completely solidified pole body adjacent said main field windings, said slot containing one side of two adjacent auxiliary field coils having a span of approximately one pole pitch, a slit within said pole head communicating said one sides of the auxiliary field windings with the airgap between the stator and rotor magnetic cores, and means for varying the relative values of the direct current applied to said main and auxiliary windings of said motor whereby the polar axes of the resultant main and auxiliary windings can be shifted to alter the sharing of load by the motor.
Claim 3
Dependent Claim
43 words
The motor of claim 1 wherein said slot retaining said auxiliary field winding is situated at the center of said pole head and said main windings completely fill a zone situated between the overhanging ledge of the pole head and the magnetic core.
Claim 4
Dependent Claim
28 words
The motor of claim 1 further including an amortisseur winding situated within axially extending slots disposed within the slit communicating the auxiliary field turns with the motor airgap.
Claim 5
Dependent Claim
28 words
The motor of claim 3 wherein said auxiliary field coils are characterized by a rectangular cross section and said amortisseur windings are characterized by a circular cross section.
Claim 6
Dependent Claim
227 words
A synchronous motor for sharing a common load comprising stator and rotor magnetic cores, an armature winding disposed on one of said cores for producing a rotating magnetic field when energized with alternating current, a main field winding characterized by a number of main field coils disposed on the bodies of pole pieces on the other of said cores to produce a multipolar steady state magnetic field when energized with direct current, said multipolar field interacting with the alternating current generated magnetic field to rotate said motor, and an auxiliary field winding characterized by a number of auxiliary field coils electrically displaced with respect to said main coils to produce a second multipolar steady state magnetic field having polar axes located between the polar axes of said main field, a plurality of axial slots extending through the heads of said pole pieces above the pole bodies to assure a completely solidified pole body adjacent said main field winding, the turns of said auxiliary field winding extending from said slots in said pole head to a zone situated between an overhanging ledge of the pole head and the main field coil disposed on said pole body, the turns of said auxiliary winding situated in axial slots on different sides of the pole piece centerline extending under the pole head on the corresponding side of the pole piece centerline.
Claim 7
Dependent Claim
227 words
A synchronous motor for sharing a common load comprising stator and rotor magnetic cores, an armature winding disposed on one of said cores for producing a rotating magnetic field when energized with alternating current, a main field winding characterized by a number of main field coils disposed on the bodies of pole pieces on the other of said cores to produce a multipolar steady state magnetic field when energized with direct current, said multipolar field interacting with the alternating current generated magnetic field to rotate said motor, and an auxiliary field winding characterized by a number of auxiliary field coils electrically displaced with respect to said main coils to produce a second multipolar steady state magnetic field having polar axes located between the polar axes of said main field, a plurality of axial slots extending through the heads of said pole pieces above the pole bodies to assure a completely solidified pole body adjacent said main field winding, the turns of said auxiliary field winding extending from said slots in said pole head to a zone situated between an overhanging ledge of the pole head and the main field coil disposed on said pole body, the turns of said auxiliary winding situated in axial slots on different sides of the pole piece centerline extending under the pole head on the corresponding side of the pole piece centerline.
Claim 8
Dependent Claim
28 words
The motor of claim 5 further including an amortisseur winding situated within axially extending slots disposed between said auxiliary field turns within said head and the motor airgap.
Claim 9
Dependent Claim
46 words
The motor of claim 6 wherein said auxiliary field coils are characterized by a rectangular cross section, said amortisseur windings are characterized by a circular cross section and said turns of said auxiliary winding on different sides of the pole piece are connected for opposite polarity.
References Cited (Backward Citations)
US3333173A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-04 | 1975-04-05 | 1975-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-04 | 1979-04-05 | 1979-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-04 | 1983-04-05 | 1983-10-05 | $7700.00 | Window Closed / Lapsed |