US5142175A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic bearing system
Assignee: Ebara Corp
•
Filing: 1991-09-06
•
Granted: 1992-08-25
•
Expires: 2011-09-06
Abstract
Abstract A system for supporting a rotor without contact with a stator comprising a magnetic bearing apparatus mounted on the stator and including a controlling magnet means fixed to the stator, a non-controlling magnetic pole fixed to the stator, a biasing magnetic poles sandwiched between the controlling magnet and the non-controlling magnetic pole, and a rotor magnetic pole fixed to the rotor to enable the magnetic path of a biasing flux to run in a plane which includes the longitudinal axis of the stator. The non-controlling and rotor magnetic poles may have teeth facing each other.
Inventors
- 👤 Katsuhide Watanabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 07:19
CPC Classifications
F; F16; F16C; F16C32/00; F16C32/04; F16C32/0406; F16C32/044; F16C32/0444; F16C32/0459
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
259 words
A system for supporting a rotor rotatably relative to a stator having a longitudinal axis and without contact with the stator and controlling a position of said rotor on at least one control axis, said system comprising: a motor means mounted on said stator for rotating said rotor; and a magnetic bearing apparatus mounted on said stator for rotatably supporting said rotor relative to said stator and including: a controlling magnet means fixed to a peripheral portion of said stator for generating a controlling magnetic flux to exert a magnetic force on said rotor so as to support said rotor in a neutral position; a non-controlling magnetic pole means fixed to the peripheral portion of said stator; a biasing magnetic pole means fixed to said stator and positioned between said controlling magnet means and said non-controlling magnetic pole means for generating and supplying a biasing magnetic flux to said controlling magnet means to linearize control of a position of said rotor; said biasing magnetic pole means being sandwiched between said controlling magnet means and said non-controlling magnetic pole means, thereby inhibiting an eddy current from being generated in said rotor; and said biasing magnetic pole means comprising an annular permanent magnet and a non-magnetic ring covering the periphery of said annular permanent magnet; and a rotor magnetic pole means fixed to said rotor to face said controlling magnet means and said non-controlling and biasing magnetic pole means, thereby forming a magnetic path for the biasing magnetic flux running in a plane which includes the longitudinal axis of said stator.
Claim 2
Independent Claim
259 words
A system for supporting a rotor rotatably relative to a stator having a longitudinal axis and without contact with the stator and controlling a position of said rotor on at least one control axis, said system comprising: a motor means mounted on said stator for rotating said rotor; and a magnetic bearing apparatus mounted on said stator for rotatably supporting said rotor relative to said stator and including: a controlling magnet means fixed to a peripheral portion of said stator for generating a controlling magnetic flux to exert a magnetic force on said rotor so as to support said rotor in a neutral position; a non-controlling magnetic pole means fixed to the peripheral portion of said stator; a biasing magnetic pole means fixed to said stator and positioned between said controlling magnet means and said non-controlling magnetic pole means for generating and supplying a biasing magnetic flux to said controlling magnet means to linearize control of a position of said rotor; said biasing magnetic pole means being sandwiched between said controlling magnet means and said non-controlling magnetic pole means, thereby inhibiting an eddy current from being generated in said rotor; and said biasing magnetic pole means comprising an annular permanent magnet and a non-magnetic ring covering the periphery of said annular permanent magnet; and a rotor magnetic pole means fixed to said rotor to face said controlling magnet means and said non-controlling and biasing magnetic pole means, thereby forming a magnetic path for the biasing magnetic flux running in a plane which includes the longitudinal axis of said stator.
Claim 3
Dependent Claim
50 words
System as set forth in claim 1 wherein said controlling magnet means comprises an annular electromagnet and a first annular magnetic pole, and said non-controlling magnetic pole means comprises a second annular magnetic pole, said first and second annular magnetic poles being provided to sandwich said biasing magnetic pole means.
Claim 4
Dependent Claim
24 words
System as set forth in claim 2 wherein said biasing magnetic pole means comprises at least one of a permanent magnet and an electromagnet.
Claim 5
Dependent Claim
19 words
System as set forth in claim 2 wherein said first annular magnetic pole includes a plurality of radial notches.
Claim 6
Dependent Claim
18 words
System as set forth in claim 2 wherein said annular electromagnet is driven by a push-pull current amplifier.
Claim 7
Dependent Claim
43 words
System as set forth in claim 2 wherein the flux density ranges from 0.4 Tesla to 0.6 Tesla at said first annular magnetic pole means and the flux density ranges from 0.8 Tesla to 1.2 Tesla at said second annular magnetic pole means.
Claim 8
Dependent Claim
24 words
System as set forth in claim 2 wherein said biasing magnetic pole means and said first and second annular magnetic poles are integrally assembled.
Claim 9
Dependent Claim
20 words
System as set forth in claim 1 further comprising a sensor means for sensing a radial displacement of said rotor.
Claim 10
Independent Claim
282 words
A system for supporting a rotor rotatably relative to a stator having a longitudinal axis and without contact with the stator and controlling the position of said rotor on at least one control axis, said system comprising: a motor means mounted on said stator for rotating said rotor; and a magnetic bearing apparatus mounted on said stator for rotatably supporting said rotor relative to said stator and including: a controlling magnet means fixed to a peripheral portion of said stator for generating a controlling magnetic flux to exert a magnetic force on said rotor so as to support said rotor in a neutral position; a non-controlling magnetic pole means fixed to the peripheral portion of said stator and having at least two first teeth on one surface thereof; a biasing magnetic pole means fixed to said stator and positioned between said controlling magnet means and said non-controlling magnetic pole means for generating and supplying a biasing magnetic flux to said controlling magnet means to linearize control of a position of said rotor; and a rotor magnetic pole means fixed to said rotor and having at least two second teeth on one surface thereof to face said first teeth of said non-controlling magnetic pole means, said biasing magnetic flux passing through a magnetic path formed by said controlling magnet means and each of said non-controlling magnetic pole means, said biasing magnetic pole means, and said rotor magnetic pole means and the gap between said first and second teeth, said magnetic path running in a plane which includes the longitudinal axis of said stator, thereby utilizing said biasing magnetic flux between said first and second teeth for recovering a longitudinal displacement of said rotor.
Claim 11
Independent Claim
282 words
A system for supporting a rotor rotatably relative to a stator having a longitudinal axis and without contact with the stator and controlling the position of said rotor on at least one control axis, said system comprising: a motor means mounted on said stator for rotating said rotor; and a magnetic bearing apparatus mounted on said stator for rotatably supporting said rotor relative to said stator and including: a controlling magnet means fixed to a peripheral portion of said stator for generating a controlling magnetic flux to exert a magnetic force on said rotor so as to support said rotor in a neutral position; a non-controlling magnetic pole means fixed to the peripheral portion of said stator and having at least two first teeth on one surface thereof; a biasing magnetic pole means fixed to said stator and positioned between said controlling magnet means and said non-controlling magnetic pole means for generating and supplying a biasing magnetic flux to said controlling magnet means to linearize control of a position of said rotor; and a rotor magnetic pole means fixed to said rotor and having at least two second teeth on one surface thereof to face said first teeth of said non-controlling magnetic pole means, said biasing magnetic flux passing through a magnetic path formed by said controlling magnet means and each of said non-controlling magnetic pole means, said biasing magnetic pole means, and said rotor magnetic pole means and the gap between said first and second teeth, said magnetic path running in a plane which includes the longitudinal axis of said stator, thereby utilizing said biasing magnetic flux between said first and second teeth for recovering a longitudinal displacement of said rotor.
Claim 12
Dependent Claim
79 words
System as set forth in claim 9 wherein said controlling magnet means comprises a control electromagnet positioned perpendicular to the radial direction of said rotor to generate a controlling magnetic flux and a controlling magnetic pole means receiving the controlling magnetic flux to exert a radial magnetic attractive force on said rotor, and wherein a magnetic path for said controlling magnetic flux is partially common to the magnetic path for said biasing magnetic flux in said controlling magnet means.
Claim 13
Dependent Claim
32 words
System as set forth in claim 10 wherein said controlling magnetic pole means and said non-controlling magnetic pole means are annular and are disposed to receive said biasing magnetic pole means therebetween.
Claim 14
Dependent Claim
34 words
System as set forth in claim 10 wherein said control electromagnet is formed such that the cross section thereof includes a straight side and an arc-shaped side connecting the ends of the straight side.
Claim 15
Dependent Claim
18 words
System as set forth in claim 10 wherein said biasing magnetic pole means comprises an annular permanent magnet.
Claim 16
Dependent Claim
26 words
System as set forth in claim 13 wherein one side surface of said permanent magnet is provided with a non-magnetic member to protect said permanent magnet.
Claim 17
Dependent Claim
17 words
System as set forth in claim 10 wherein said biasing magnetic pole means comprises an annular electromagnet.
Claim 18
Dependent Claim
20 words
System as set forth in claim 10 further comprising a sensor means for sensing a radial displacement of said rotor.
Claim 19
Dependent Claim
176 words
A magnetic bearing apparatus for rotatably supporting a rotor in a non-contact state relative to a stator having a longitudinal axis and controlling the position of the rotor on at least one control axis, said apparatus comprising: a controlling magnet means fixed to a peripheral portion of said stator for generating a controlling magnetic flux to exert a magnetic force on said rotor so as to support said rotor in a neutral position; a non-controlling magnetic pole means fixed to the peripheral portion of said stator; a biasing magnetic pole means fixed to said stator and positioned between said controlling magnet means and said non-controlling magnetic pole means for generating and supplying a biasing magnetic flux to said controlling magnet means to linearize control of the position of said rotor; and a rotor magnetic pole means fixed to said rotor to face said controlling magnet means and said non-controlling and biasing magnetic pole means, thereby forming a magnetic path of said biasing magnetic flux running in a plane which includes the longitudinal axis of said stator.
Claim 20
Dependent Claim
176 words
A magnetic bearing apparatus for rotatably supporting a rotor in a non-contact state relative to a stator having a longitudinal axis and controlling the position of the rotor on at least one control axis, said apparatus comprising: a controlling magnet means fixed to a peripheral portion of said stator for generating a controlling magnetic flux to exert a magnetic force on said rotor so as to support said rotor in a neutral position; a non-controlling magnetic pole means fixed to the peripheral portion of said stator; a biasing magnetic pole means fixed to said stator and positioned between said controlling magnet means and said non-controlling magnetic pole means for generating and supplying a biasing magnetic flux to said controlling magnet means to linearize control of the position of said rotor; and a rotor magnetic pole means fixed to said rotor to face said controlling magnet means and said non-controlling and biasing magnetic pole means, thereby forming a magnetic path of said biasing magnetic flux running in a plane which includes the longitudinal axis of said stator.
Claim 21
Dependent Claim
37 words
Apparatus as set forth in claim 17 wherein said biasing magnetic pole means is sandwiched between said controlling magnet means and said non-controlling magnetic pole means, thereby inhibiting an eddy current from being generated in said rotor.
Claim 22
Dependent Claim
53 words
Apparatus as set forth in claim 18 wherein said controlling magnet means comprises an annular electromagnet and a first annular magnetic pole means, and said non-controlling magnetic pole means comprises a second annular magnetic pole means, said first and second annular magnetic pole means being provided to sandwich said biasing magnetic pole means.
Claim 23
Dependent Claim
20 words
Apparatus as set forth in claim 18 wherein said biasing magnetic pole means comprises a permanent magnet or an electromagnet.
Claim 24
Dependent Claim
256 words
A magnetic bearing apparatus for supporting a rotor rotatably relative to a stator having a longitudinal axis and without contact with the stator and controlling the position of the rotor on at least one control axis, said apparatus comprising: a controlling magnet means fixed to a peripheral portion of said stator for generating a controlling magnetic flux to exert a magnetic force on said rotor so as to support said rotor in a neutral position; a non-controlling magnetic pole means fixed to said peripheral portion of said stator and having at least two first teeth on one surface thereof; a biasing magnetic pole means fixed to said stator and positioned between said controlling magnet means and said non-controlling magnetic pole means for generating and supplying a biasing magnetic flux to said controlling magnet means to linearize control of a position of said rotor; and a rotor magnetic pole means fixed to said rotor and having at least two second teeth on one surface thereof to face said first teeth of said non-controlling magnetic pole means, said biasing magnetic flux passing through a magnetic path formed by said controlling magnet means and each of said non-controlling magnetic pole means, said biasing magnetic pole means, and said rotor magnetic pole means and the gap between said first and second teeth, said magnetic path running in a plane which includes the longitudinal axis of said stator, thereby utilizing the magnetic flux between said first and second teeth as a magnetic flux for recovering a longitudinal displacement of said rotor.
Claim 25
Dependent Claim
256 words
A magnetic bearing apparatus for supporting a rotor rotatably relative to a stator having a longitudinal axis and without contact with the stator and controlling the position of the rotor on at least one control axis, said apparatus comprising: a controlling magnet means fixed to a peripheral portion of said stator for generating a controlling magnetic flux to exert a magnetic force on said rotor so as to support said rotor in a neutral position; a non-controlling magnetic pole means fixed to said peripheral portion of said stator and having at least two first teeth on one surface thereof; a biasing magnetic pole means fixed to said stator and positioned between said controlling magnet means and said non-controlling magnetic pole means for generating and supplying a biasing magnetic flux to said controlling magnet means to linearize control of a position of said rotor; and a rotor magnetic pole means fixed to said rotor and having at least two second teeth on one surface thereof to face said first teeth of said non-controlling magnetic pole means, said biasing magnetic flux passing through a magnetic path formed by said controlling magnet means and each of said non-controlling magnetic pole means, said biasing magnetic pole means, and said rotor magnetic pole means and the gap between said first and second teeth, said magnetic path running in a plane which includes the longitudinal axis of said stator, thereby utilizing the magnetic flux between said first and second teeth as a magnetic flux for recovering a longitudinal displacement of said rotor.
Claim 26
Dependent Claim
80 words
Apparatus as set forth in claim 21 wherein said controlling magnet means comprises a control electromagnet positioned perpendicularly to the radial direction of said rotor to generate a controlling magnetic flux and a controlling magnetic pole means receiving the controlling magnetic flux to exert a radial magnetic attractive force on said rotor, and wherein a magnetic path of said controlling magnetic flux is partially common to the magnetic path of said biasing magnetic flux in said controlling magnetic pole means.
Claim 27
Dependent Claim
31 words
Apparatus as set forth in claim 22 wherein said controlling magnet means and said non-controlling magnetic pole means are annular and are disposed to receive said biasing magnetic pole means therebetween.
Claim 28
Dependent Claim
34 words
Apparatus as set forth in claim 22 wherein said control electromagnet is formed such that the cross section thereof includes a straight side and an arc-shaped side connecting the ends of the straight side.
Claim 29
Dependent Claim
18 words
Apparatus as set forth in claim 22 wherein said biasing magnetic pole means comprises an annular permanent magnet.
Claim 30
Dependent Claim
25 words
Apparatus as set forth in claim 25 wherein one surface of said permanent magnet is provided with a non-magnetic member to protect said permanent magnet.
Claim 31
Dependent Claim
17 words
Apparatus as set forth in claim 22 wherein said biasing magnetic pole means comprises an annular electromagnet.
Claim 32
Independent Claim
245 words
A system for supporting a rotor rotatably relative to a stator having a longitudinal axis and without contact with the stator and controlling a position of said rotor on at least one control axis, said system comprising: a motor means mounted on said stator for rotating said rotor; and a magnetic bearing apparatus mounted on said stator for rotatably supporting said rotor relative to said stator and including: a controlling magnet means fixed to a peripheral portion of said stator for generating a controlling magnetic flux to exert a magnetic force on said rotor so as to support said rotor in a neutral position; a non-controlling magnetic pole means fixed to the peripheral portion of said stator; a biasing magnetic pole means fixed to said stator and positioned between said controlling magnet means and said non-controlling magnetic pole means for generating and supplying a biasing magnetic flux to said controlling magnet means to linearize control of a position of said rotor; said biasing magnetic pole means being sandwiched between said controlling magnet means and said non-controlling magnetic pole means, thereby inhibiting an eddy current from being generated in said rotor; and said biasing magnetic pole means comprising an electromagnet; and a rotor magnetic pole means fixed to said rotor to face said controlling magnet means and said non-controlling and biasing magnetic pole means, thereby forming a magnetic path for the biasing magnetic flux running in a plane which includes the longitudinal axis of said stator.
Claim 33
Independent Claim
245 words
A system for supporting a rotor rotatably relative to a stator having a longitudinal axis and without contact with the stator and controlling a position of said rotor on at least one control axis, said system comprising: a motor means mounted on said stator for rotating said rotor; and a magnetic bearing apparatus mounted on said stator for rotatably supporting said rotor relative to said stator and including: a controlling magnet means fixed to a peripheral portion of said stator for generating a controlling magnetic flux to exert a magnetic force on said rotor so as to support said rotor in a neutral position; a non-controlling magnetic pole means fixed to the peripheral portion of said stator; a biasing magnetic pole means fixed to said stator and positioned between said controlling magnet means and said non-controlling magnetic pole means for generating and supplying a biasing magnetic flux to said controlling magnet means to linearize control of a position of said rotor; said biasing magnetic pole means being sandwiched between said controlling magnet means and said non-controlling magnetic pole means, thereby inhibiting an eddy current from being generated in said rotor; and said biasing magnetic pole means comprising an electromagnet; and a rotor magnetic pole means fixed to said rotor to face said controlling magnet means and said non-controlling and biasing magnetic pole means, thereby forming a magnetic path for the biasing magnetic flux running in a plane which includes the longitudinal axis of said stator.
References Cited (Backward Citations)
US3650581A
Cited
US3823990A
Cited
US3955858A
Cited
US4088379A
Cited
US4211452A
Cited
US4312628A
Cited
JPS5730998A
Cited
JPS57137740A
Cited
JPS5854220A
Cited
EP0136865A2
Cited
JPS60256620A
Cited
US4700094A
Cited
US4634191A
Cited
EP0311122A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-08-25 | 1996-02-24 | 1996-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-08-25 | 2000-02-24 | 2000-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-08-25 | 2004-02-24 | 2004-08-25 | $7700.00 | Window Closed / Lapsed |