US3694041A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric motive machine including magnetic bearing
Assignee: National Aeronautics and Space Administration
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Filing: 1971-01-08
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Granted: 1972-09-26
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Expires: 1991-01-08
Abstract
Abstract A d.c. motor includes a plurality of stationary field windings and a stationary armature winding. Magnetic fluxes derived from the field windings interact with currents in the armature winding to produce a torque that rotatably drives a rotor about an axis that has a tendency to coincide with a common longitudinal axis for the armature and field windings. The displacement of the rotor axis relative to the common axis is sensed to provide a signal for controlling the currents in the field windings. The currents in the field windings displace the rotor so that the rotor axis has a tendency to coincide with the common axis. The rotor is thereby magnetically suspended, without mechanical or air bearings, by the same forces that rotate it. To maintain the rotor speed constant, the total current in the field windings is maintained constant.
Inventors
- 👤 Philip A Studer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:03
CPC Classifications
F; F16; F16C; F16C32/00; F16C32/04; F16C32/0406; F16C32/044; F16C32/0474; F16C32/0493; H; H02; H02K; H02K29/00; H02K29/06; H02K29/10; H02K7/00; H02K7/08; H02K7/09; F16C2380/00; F16C2380/26
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
113 words
AN ELECTRIC MOTIVE MACHINE COMPRISING A PLURALITY OF SEPARATE FIELD WINDINGS, AN ARMATURE WINDING, MEANS FOR PROVIDING CURRENT FLOW IN SAID FIELD WINDINGS, MEANS FOR PROVIDING CURRENT FLOW IN SAID ARMATURE WINDING, A ROTOR FOR COUPLING FLUX DERIVED FROM THE FIELD WINDINGS IN AN INTERACTING RELATIONSHIP WITH CURRENT FLOWING IN THE ARMATURE WINDING WHEREBY THE ROTOR IS DRIVEN RELATIVE TO THE FIELD WINDINGS IN RESPONSE TO THE INTERACTION, MEANS FOR SENSING THE POSITION OF THE ROTOR RELATIVE TO THE FIELD WINDINGS, AND MEANS RESPONSIVE TO THE SENSING MEANS FOR CONTROLLING THE RELATIVE AMPLITUDES OF CURRENT FLOWING IN SAID FIELD WINDINGS TO MAINTAIN SAID ROTOR IN A PREDETERMINED POSITION RELATIVE TO THE FIELD WINDINGS.
Claim 2
Dependent Claim
113 words
AN ELECTRIC MOTIVE MACHINE COMPRISING A PLURALITY OF SEPARATE FIELD WINDINGS, AN ARMATURE WINDING, MEANS FOR PROVIDING CURRENT FLOW IN SAID FIELD WINDINGS, MEANS FOR PROVIDING CURRENT FLOW IN SAID ARMATURE WINDING, A ROTOR FOR COUPLING FLUX DERIVED FROM THE FIELD WINDINGS IN AN INTERACTING RELATIONSHIP WITH CURRENT FLOWING IN THE ARMATURE WINDING WHEREBY THE ROTOR IS DRIVEN RELATIVE TO THE FIELD WINDINGS IN RESPONSE TO THE INTERACTION, MEANS FOR SENSING THE POSITION OF THE ROTOR RELATIVE TO THE FIELD WINDINGS, AND MEANS RESPONSIVE TO THE SENSING MEANS FOR CONTROLLING THE RELATIVE AMPLITUDES OF CURRENT FLOWING IN SAID FIELD WINDINGS TO MAINTAIN SAID ROTOR IN A PREDETERMINED POSITION RELATIVE TO THE FIELD WINDINGS.
Claim 3
Dependent Claim
18 words
The machine of claim 1 wherein the armature includes a winding fixedly mounted relative to the field windings.
Claim 4
Dependent Claim
20 words
The machine of claim 1 wherein the means for controlling maintains the total current in said field windings substantially constant.
Claim 5
Dependent Claim
43 words
The machine of claim 1 including means for supplying d.c. currents to said field windings and further including commutator means responsive to the motion of the rotor resulting from the interaction, said commutator means controlling the flow of d.c. current in the armature.
Claim 6
Dependent Claim
19 words
The machine of claim 4 wherein the commutator means senses the position of the rotor without contacting the rotor.
Claim 7
Dependent Claim
138 words
An electric motive machine comprising four field windings fixedly mounted along radii angularly displaced 90* from each other relative to a longitudinal axis, an armature including a winding, a rotor having an axis, a magnetic circuit including the field windings, rotor, and armature, said magnetic circuit producing a torque in the rotor in response to an interaction between current flowing in the armature winding and magnetic flux derived from the field windings, said torque rotating said rotor about the rotor axis, means tending to align said rotor axis with the longitudinal axis, said last named means including: position sensors for the radial position of the rotor along radii from the longitudinal axis, said radii being angularly displaced 90* from each other, and means responsive to the sensors for controlling the relative amplitudes of currents in the field windings.
Claim 8
Dependent Claim
138 words
An electric motive machine comprising four field windings fixedly mounted along radii angularly displaced 90* from each other relative to a longitudinal axis, an armature including a winding, a rotor having an axis, a magnetic circuit including the field windings, rotor, and armature, said magnetic circuit producing a torque in the rotor in response to an interaction between current flowing in the armature winding and magnetic flux derived from the field windings, said torque rotating said rotor about the rotor axis, means tending to align said rotor axis with the longitudinal axis, said last named means including: position sensors for the radial position of the rotor along radii from the longitudinal axis, said radii being angularly displaced 90* from each other, and means responsive to the sensors for controlling the relative amplitudes of currents in the field windings.
Claim 9
Dependent Claim
20 words
The machine of claim 6 wherein the means for controlling includes means for maintaining the total field winding current constant.
Claim 10
Dependent Claim
16 words
The machine of claim 6 wherein the position sensors are radially aligned with the field windings.
Claim 11
Dependent Claim
24 words
The machine of claim 6 wherein the armature is fixed relative to the field windings and has an axis coincident with the longitudinal axis.
Claim 12
Dependent Claim
49 words
The machine of claim 9 wherein the rotor includes a pair of low magnetic reluctance pole pieces, said pole pieces being included in said magnetic circuit so that magnetic flux flows from one of said pole pieces into the armature and from the armature into the other pole piece.
Claim 13
Dependent Claim
75 words
The machine of claim 6 wherein two pairs of said position sensors are provided, the sensors of one of said pairs being equidistant from and on opposite sides of the longitudinal axis and on radii coincident with a first pair of said field windings, the sensors of the second of said pairs being equidistant from and on opposite sides of the longitudinal axis and on radii coincident with a second pair of said field windings.
Claim 14
Dependent Claim
68 words
The machine of claim 11 further including means for controlling the relative currents in the first pair of field windings in response to the difference in position detected by The sensors of the first pair of sensors, and means for controlling the relative currents in the second pair of field windings in response to the difference in position detected by the sensors of the second pair of sensors.
Claim 15
Dependent Claim
53 words
The machine of claim 12 further including means for maintaining the sum of the currents in the first pair of field windings at a fixed level, and means for maintaining the sum of the currents in the second pair of field windings at a second fixed level equal to the first fixed level.
Claim 16
Dependent Claim
25 words
The machine of claim 6 further including commutator means responsive to rotation of the rotor for controlling the direction current flows through the armature winding.
Claim 17
Dependent Claim
148 words
An electric motive device comprising electromagnet means for deriving a magnetic flux, an armature winding fixedly positioned with respect to said electromagnet means, a magnetic rotor mechanically free of said electromagnet means and said winding, means establishing for the derived magnetic flux a moving magnetic flux path through the rotor and the winding in such a manner as to drive the rotor in a first sense in response to interacting forces between magnetic flux in the armature resulting from current flowing in the armature and the magnetic flux in the rotor and armature, means sensing the position of the rotor relative to the armature for deriving a signal indicative of the relative position of the armature and rotor in a second sense, and means responsive to the signal for controlling the current applied to the electromagnet means to control the position of the rotor in the second sense.
Claim 18
Dependent Claim
148 words
An electric motive device comprising electromagnet means for deriving a magnetic flux, an armature winding fixedly positioned with respect to said electromagnet means, a magnetic rotor mechanically free of said electromagnet means and said winding, means establishing for the derived magnetic flux a moving magnetic flux path through the rotor and the winding in such a manner as to drive the rotor in a first sense in response to interacting forces between magnetic flux in the armature resulting from current flowing in the armature and the magnetic flux in the rotor and armature, means sensing the position of the rotor relative to the armature for deriving a signal indicative of the relative position of the armature and rotor in a second sense, and means responsive to the signal for controlling the current applied to the electromagnet means to control the position of the rotor in the second sense.
Claim 19
Dependent Claim
149 words
An electric motive device comprising a plurality of field windings forming electromagnets, an armature including a winding, a rotor, said armature and field windings being fixedly mounted relative to each other, said rotor being mechanically free of the armature and field windings, a magnetic circuit including the field windings, rotor, and armature, said magnetic circuit including means for establishing a moving magnetic field to drive the rotor in a first sense in response to an interaction between current flowing in the armature winding and magnetic flux derived from the field windings, means sensing the position of the rotor relative to the armature for deriving a signal indicative of the relative position of the armature and rotor in a second sense, and means responsive to the signal for controlling the relative amplitudes of currents applied to the field windings to control the position of the rotor in the second sense.
Claim 20
Dependent Claim
149 words
An electric motive device comprising a plurality of field windings forming electromagnets, an armature including a winding, a rotor, said armature and field windings being fixedly mounted relative to each other, said rotor being mechanically free of the armature and field windings, a magnetic circuit including the field windings, rotor, and armature, said magnetic circuit including means for establishing a moving magnetic field to drive the rotor in a first sense in response to an interaction between current flowing in the armature winding and magnetic flux derived from the field windings, means sensing the position of the rotor relative to the armature for deriving a signal indicative of the relative position of the armature and rotor in a second sense, and means responsive to the signal for controlling the relative amplitudes of currents applied to the field windings to control the position of the rotor in the second sense.
Claim 21
Dependent Claim
138 words
An electric motive machine comprising a plurality of field windings fixedly mounted along radii angularly displaced from each other relative to a longitudinal axis, an armature including a winding, a rotor having an axis, a magnetic circuit including the field windings, rotor, and armature, said magnetic circuit producing a torque in the rotor in response to an interaction between current flowing in the armature winding and magnetic flux derived from the field windings, said torque rotating said rotor about the rotor axis, means tending to align said rotor axis with the longitudinal axis, said last named means including: position sensors for the radial position of the rotor along radii from the longitudinal axis, said radii being angularly displaced from each other, and means responsive to the sensors for controlling the relative amplitudes of currents in the field windings.
Claim 22
Dependent Claim
138 words
An electric motive machine comprising a plurality of field windings fixedly mounted along radii angularly displaced from each other relative to a longitudinal axis, an armature including a winding, a rotor having an axis, a magnetic circuit including the field windings, rotor, and armature, said magnetic circuit producing a torque in the rotor in response to an interaction between current flowing in the armature winding and magnetic flux derived from the field windings, said torque rotating said rotor about the rotor axis, means tending to align said rotor axis with the longitudinal axis, said last named means including: position sensors for the radial position of the rotor along radii from the longitudinal axis, said radii being angularly displaced from each other, and means responsive to the sensors for controlling the relative amplitudes of currents in the field windings.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-09-26 | 1976-03-27 | 1976-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-26 | 1980-03-27 | 1980-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-26 | 1984-03-27 | 1984-09-26 | $7700.00 | Window Closed / Lapsed |