US5525848A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic bearing system including a generator
Assignee: Magnetic Bearing Technologies Inc
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Filing: 1994-04-12
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Granted: 1996-06-11
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Expires: 2014-04-12
Abstract
Abstract A magnetic bearing system has a magnetic bearing and an electric generator for activating the magnetic bearing. The various components of the system are mounted respectively on a rotor and a stator. The magnetic bearing is of the magnetic attraction type or of the Lorentz force type. It has first and second subassemblies, one of which is on the rotor and the other of which is on the stator. The generator has at least one magnet subassembly and at least one loop subassembly, one of which is on the rotor and the other of which is on the stator. The magnet subassembly has field magnets for creating magnetic fields. The loop subassembly has loops which travel through the magnetic fields. The magnetic fields are positioned where (a) they subject the interior of a loop moving therethrough to magnetic flux which produces equal and opposed electromotive forces in the loop when the loop is on a prescribed circular path, and (b) they subject the loop's interior to flux which produces unequal and opposed electromotive forces in the loop when the loop deviates from its prescribed circular path. The latter induces, in the generator loop, an electric current which is proportional to the displacement of the loop from its prescribed path. The generator loop is electrically connected to a coil in the bearing so that the generator activates the bearing whenever the generator loop deviates from its prescribed circular path.
Inventors
- 👤 Joseph F. Pinkerton
- 👤 David B. Clifton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:02
CPC Classifications
F; F16; F16C; F16C32/00; F16C32/04; F16C32/0406; F16C32/0408; F16C32/0436; F16C32/044; F16C32/0444; F16C32/0457; F16C41/00; F16C41/004; H; H02; H02K; H02K7/00; H02K7/08; H02K7/09; H02K7/18; H02K7/1807
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
327 words
A magnetic bearing system, comprising, a stator assembly, a rotor assembly which is rotatable relative to said stator assembly, a magnetic bearing for supporting the rotor assembly at a prescribed position relative to the stator assembly, said magnetic bearing having a first rotor-positioning subassembly and a second rotor-positioning subassembly, said rotor-positioning subassemblies of said magnetic bearing being mounted on different said assemblies; an electric generator for providing an output voltage which varies in response to deviations of the rotor assembly from its said prescribed position, said electric generator having a magnet subassembly and a loop subassembly, said magnet and loop subassemblies of said electric generator being mounted on different said assemblies; said loop subassembly including a loop of electrically conductive material, said magnet subassembly of said electric generator including a plurality of field magnets which each produce at least one magnetic field, said stator assembly and said rotor assembly being relatively positioned and rotatable about an axis of rotation so that said loop follows a prescribed circular path relative to and through said magnetic fields produced by the field magnets, said magnetic fields produced by the field magnets being positioned (a) to subject the interior of said loop to magnetic flux to produce equal and opposed electromotive forces in said loop when said loop is on its prescribed circular path so that no net voltage is generated in said loop, and (b) to subject the interior of said loop to magnetic flux to produce unequal and opposed electromotive forces in said loop when said loop deviates from its prescribed circular path so that a net voltage is induced in said loop, said first rotor-positioning subassembly of the magnetic bearing having coils formed of electrical conductors, said loop of the electric generator being electrically connected to at least one of said coils whereby net voltages induced in said loop will drive currents to activate the magnetic bearing in a direction which moves said loop toward its prescribed path.
Claim 2
Dependent Claim
327 words
A magnetic bearing system, comprising, a stator assembly, a rotor assembly which is rotatable relative to said stator assembly, a magnetic bearing for supporting the rotor assembly at a prescribed position relative to the stator assembly, said magnetic bearing having a first rotor-positioning subassembly and a second rotor-positioning subassembly, said rotor-positioning subassemblies of said magnetic bearing being mounted on different said assemblies; an electric generator for providing an output voltage which varies in response to deviations of the rotor assembly from its said prescribed position, said electric generator having a magnet subassembly and a loop subassembly, said magnet and loop subassemblies of said electric generator being mounted on different said assemblies; said loop subassembly including a loop of electrically conductive material, said magnet subassembly of said electric generator including a plurality of field magnets which each produce at least one magnetic field, said stator assembly and said rotor assembly being relatively positioned and rotatable about an axis of rotation so that said loop follows a prescribed circular path relative to and through said magnetic fields produced by the field magnets, said magnetic fields produced by the field magnets being positioned (a) to subject the interior of said loop to magnetic flux to produce equal and opposed electromotive forces in said loop when said loop is on its prescribed circular path so that no net voltage is generated in said loop, and (b) to subject the interior of said loop to magnetic flux to produce unequal and opposed electromotive forces in said loop when said loop deviates from its prescribed circular path so that a net voltage is induced in said loop, said first rotor-positioning subassembly of the magnetic bearing having coils formed of electrical conductors, said loop of the electric generator being electrically connected to at least one of said coils whereby net voltages induced in said loop will drive currents to activate the magnetic bearing in a direction which moves said loop toward its prescribed path.
Claim 3
Dependent Claim
54 words
A magnetic bearing system according to claim 1 wherein said magnetic bearing utilizes magnetic attraction forces for positioning the rotor assembly relative to the stator assembly, said first rotor-positioning subassembly including first and second electromagnets, said second rotor-positioning subassembly including a body which is magnetically attractable by said electromagnets, said coils being electromagnet windings.
Claim 4
Dependent Claim
79 words
A magnetic bearing system according to claim 1 wherein said magnetic bearing utilizes Lorentz forces for positioning the rotor assembly relative to the stator assembly, said coils of said first rotor-positioning subassembly being a plurality of bearing loops, said second rotor-positioning subassembly having a plurality of bearing field magnets which each produce at least one magnetic field, said bearing loops moving along a prescribed circular path relative to and through said magnetic fields produced by said bearing field magnets.
Claim 5
Dependent Claim
81 words
A magnetic bearing system according to claim 1 wherein one of said magnet subassembly and said loop subassembly is a displaceable subassembly which is movably mounted on its respective assembly, said displaceable subassembly having a normal position which it occupies when said loop is traveling in its prescribed circular path, said displaceable subassembly being movable on its respective assembly in only one direction of movement from its normal position, said one direction being lateral with respect to said prescribed circular path.
Claim 6
Dependent Claim
34 words
A magnetic bearing system according to claim 4 wherein said magnetic bearing system includes two said electric generators which each have a said displaceable subassembly, said displaceable subassemblies having opposite said directions of movement.
Claim 7
Dependent Claim
47 words
A magnetic bearing system according to claim 4 wherein said displaceable subassembly is supported by a flexible member on one said assembly, and said one assembly includes a stop surface which obstructs movement of said displaceable subassembly in a direction which is opposite to said one direction.
Claim 8
Dependent Claim
18 words
A magnetic bearing system according to claim 6 wherein the flexible member is made of resilient sheet material.
Claim 9
Dependent Claim
28 words
A magnetic bearing system according to claim 4, further including a rectifier, wherein current is transmitted from said loop to said at least one coil through said rectifier.
Claim 10
Dependent Claim
62 words
A magnetic bearing system according to claim 1, further including a signal generator for generating first electrical signals in synchronism with rotation of said rotor assembly, and a first controller operable in response to said electrical signals for controlling the flow of current from said electric generator to said at least one coil of said first rotor-positioning subassembly of said magnetic bearing.
Claim 11
Dependent Claim
33 words
A magnetic bearing system according to claim 9, wherein said signal generator includes a magnet mount subassembly and a conductor subassembly, said subassemblies of said signal generator being mounted on different said assemblies.
Claim 12
Dependent Claim
29 words
A magnetic bearing system according to claim 10, wherein said magnet mount subassembly includes a plurality of magnetic poles equally spaced about its respective assembly in a circumferential direction.
Claim 13
Dependent Claim
27 words
A magnetic bearing system according to claim 11, wherein said loop subassembly includes a plurality of loops equally spaced about its respective assembly in a circumferential direction.
Claim 14
Dependent Claim
28 words
A magnetic bearing system according to claim 12, wherein a number of said plurality of said closed loops is twice a number of said plurality of magnetic poles.
Claim 15
Dependent Claim
59 words
A magnetic bearing system according to claim 9, wherein said coils include a first coil for activating said first assembly to apply force to said stator assembly from said rotor assembly in a first direction, and a second coil for activating said first assembly to apply force to said stator assembly from said rotor assembly in a second direction.
Claim 16
Dependent Claim
44 words
A magnetic bearing system according to claim 14, wherein said first controller includes a first rectifier and a second rectifier, whereby voltage is applied from said loop to said first coil through said first rectifier, and to said second coil through said second rectifier.
Claim 17
Dependent Claim
26 words
A magnetic bearing system according to claim 15, wherein said first rectifier is a controlled rectifier which is activated in response to said first electrical signals.
Claim 18
Dependent Claim
27 words
A magnetic bearing system according to claim 14, wherein said signal generator generates second electrical pulses which occur at different shaft angles from said first electrical signals.
Claim 19
Dependent Claim
29 words
A magnetic bearing system according to claim 17, wherein said signal generator produces second electrical signals which are 180 electrical degrees out of phase from said first electrical signals.
Claim 20
Dependent Claim
33 words
A magnetic bearing system according to claim 17, wherein said signal generator includes a magnet mount subassembly and a conductor subassembly, said subassemblies of said signal generator being mounted on different said assemblies.
Claim 21
Dependent Claim
29 words
A magnetic bearing system according to claim 19, wherein said magnet mount subassembly includes a plurality of magnetic poles equally spaced about its respective assembly in a radial direction.
Claim 22
Dependent Claim
38 words
A magnetic bearing system according to claim 19, wherein said conductor subassembly includes a first conductive winding and a second conductive winding, said second conductive winding being circumferentially displace on said conductor subassembly from said first conductive winding.
Claim 23
Dependent Claim
22 words
A magnetic bearing system according to claim 21, wherein said second conductive winding is circumferentially displaced 45° from said first conductive winding.
Claim 24
Dependent Claim
26 words
A magnetic bearing system according to claim 17, wherein said second rectifier is a controlled rectifier which is activated in response to said second electrical signals.
Claim 25
Dependent Claim
151 words
A magnetic bearing system according to claim 1, wherein said electric generator further includes a position sensor for sensing a deviation of said rotor assembly from its prescribed position relative of said stator assembly relative to said rotor assembly, said magnet subassembly of said electric generator includes a plurality of electromagnets which each produce at least one magnetic field in response to said position sensor sensing a displacement of said rotor assembly from its prescribed position relative to said stator which deviates said loop from its prescribed path, said electromagnets being positioned such that said net magnetic fields produced by said electromagnets cooperate with said magnetic fields produced by said field magnets in subjecting the interior of said loop to magnetic flux to produce unequal and opposed electromotive forces in said loop when said loop deviates from its prescribed circular path so that an electrical current is induced in said loop.
Claim 26
Dependent Claim
36 words
A magnetic bearing system according to claim 1, wherein said electric generator provides an output voltage which varies linearly in response to deviations of said rotor assembly from its prescribed position relative to said stator assembly.
Claim 27
Dependent Claim
83 words
A magnetic bearing system according to claim 1, wherein said electric generator provides an alternating voltage output which has (a) a first phase when said rotor assembly deviates in a first direction from its prescribed position relative to said stator assembly direction, and (b) a second phase when said rotor assembly deviates in a second direction from its prescribed position, said second direction being opposite to said first direction, said first and second phases being shifted 180 electrical degrees relative to each other.
Claim 28
Dependent Claim
297 words
A magnetic bearing system, comprising, a stator assembly, a rotor assembly which is rotatable relative to said stator assembly, a magnetic bearing for supporting the rotor assembly at a prescribed position relative to the stator assembly, said magnetic bearing having a first rotor-positioning subassembly and a second rotor-positioning subassembly, said rotor-positioning subassemblies of said magnetic bearing being mounted on different said assemblies; an electric generator for providing an output voltage which varies in response to deviations of the rotor assembly from its said prescribed position, said electric generator having a magnet subassembly and a loop subassembly, said subassemblies of said electric generator being mounted on different said assemblies; said loop subassembly including a loop of electrically conductive material, said magnet subassembly of said electric generator including a plurality of field magnets which each produce at least one magnetic field, said stator assembly and said rotor assembly being relatively positioned and rotatable about an axis of rotation so that said loop follows a circular path relative to and through said magnetic fields produced by the field magnets, said magnetic fields produced by the field magnets being positioned to subject the loop to magnetic flux to produce opposed electromotive forces in said loop when said loop travels in its circular path relative to said magnetic fields, said opposed electromotive forces producing in said loop a voltage which varies in response to changes in the position of said loop relative to its prescribed position, said first rotor-positioning subassembly of the magnetic bearing having coils formed of electrical conductors, said loop of the electric generator being electrically connected to at least one of said coils whereby net voltages induced in said loop will drive currents to activate the magnetic bearing in a direction which moves said loop toward its prescribed path.
Claim 29
Dependent Claim
297 words
A magnetic bearing system, comprising, a stator assembly, a rotor assembly which is rotatable relative to said stator assembly, a magnetic bearing for supporting the rotor assembly at a prescribed position relative to the stator assembly, said magnetic bearing having a first rotor-positioning subassembly and a second rotor-positioning subassembly, said rotor-positioning subassemblies of said magnetic bearing being mounted on different said assemblies; an electric generator for providing an output voltage which varies in response to deviations of the rotor assembly from its said prescribed position, said electric generator having a magnet subassembly and a loop subassembly, said subassemblies of said electric generator being mounted on different said assemblies; said loop subassembly including a loop of electrically conductive material, said magnet subassembly of said electric generator including a plurality of field magnets which each produce at least one magnetic field, said stator assembly and said rotor assembly being relatively positioned and rotatable about an axis of rotation so that said loop follows a circular path relative to and through said magnetic fields produced by the field magnets, said magnetic fields produced by the field magnets being positioned to subject the loop to magnetic flux to produce opposed electromotive forces in said loop when said loop travels in its circular path relative to said magnetic fields, said opposed electromotive forces producing in said loop a voltage which varies in response to changes in the position of said loop relative to its prescribed position, said first rotor-positioning subassembly of the magnetic bearing having coils formed of electrical conductors, said loop of the electric generator being electrically connected to at least one of said coils whereby net voltages induced in said loop will drive currents to activate the magnetic bearing in a direction which moves said loop toward its prescribed path.
Claim 30
Dependent Claim
36 words
A magnetic bearing system according to claim 27 wherein said field magnets are positioned to produce equal opposed electromotive forces and a zero voltage in said loop when the rotor assembly is at said prescribed position.
Claim 31
Dependent Claim
17 words
A magnetic bearing system according to claim 27 wherein said loop is mounted on said stator assembly.
Claim 32
Dependent Claim
54 words
A magnetic bearing system according to claim 27 wherein said magnetic bearing utilizes magnetic attraction forces for positioning the rotor assembly relative to the stator assembly, said first rotor-positioning subassembly including first and second electromagnets, said second rotor-positioning subassembly including a body which is magnetically attractable by said electromagnets, said coils being electromagnet windings.
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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) | 1999-06-11 | 1999-12-11 | 2000-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-06-11 | 2003-12-11 | 2004-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-06-11 | 2007-12-11 | 2008-06-11 | $7700.00 | Window Closed / Lapsed |