Rotation-speed-independent stabilizer for passive magnetic bearing systems

Patent metadata

Field	Value
Publication number	US-10180163-B2
Application number	US-201414512280-A
Country	US
Kind code	B2
Filing date	Oct 10, 2014
Priority date	Oct 10, 2014
Publication date	Jan 15, 2019
Grant date	Jan 15, 2019

Abstract

By employing a combination of magnetic forces and those from electrostatic fields, a new stabilizer is able, unlike those employing dynamic effects, to function at any speed with no need for sensors or dynamically generated electrical currents. Embodiments are provided that stabilize the radial, axial and tilt instability. In addition to its use for stabilization, the radial stabilizer described herein also functions as an eccentricity detector.

First claim

I claim:

1. An apparatus, comprising:
a rotatable cylinder having a central longitudinal axis;
means for utilizing static electrostatic forces to stabilize at least one instability of said cylinder, wherein said at least one instability is selected from the group consisting of radial, axial and tilt; and
means for utilizing magnetic forces between permanent magnets to stabilize any instability of said group that is not stabilized by said static electrostatic forces, wherein said means for utilizing static electrostatic forces to stabilize at least one instability of said cylinder comprises:
a single first ring centered on said axis, concentric with, fixedly attached to, and electrically isolated from said cylinder, said single first ring having a first diameter and comprising material selected from the group consisting of dielectric or metal;
a stationary single second ring centered on said axis, concentric with said cylinder and having a second diameter overlapping said first diameter and comprising metal;
a stationary single third ring centered on said axis, concentric with said cylinder and having a third diameter overlapping said first diameter and comprising metal, wherein said single first ring is between and spaced from said single second ring and said single third ring; and
a first power supply having a first lead and a second lead, wherein said first lead is connected to said single second ring and said second lead is connected to said single third ring.

2. The apparatus of claim 1 , wherein said first power supply is selected from a group consisting of a source of dc voltage and a source of rf voltage.

3. The apparatus of claim 1 , wherein said first ring is located above the center line of said cylinder.

4. The apparatus of claim 1 , wherein said first ring is located above the top of said rotor.

5. The apparatus of claim 1 , wherein said first ring is attached to said cylinder with a support rod attached to said cylinder by a support structure which spans said cylinder, wherein said support rod is fixed to be coaxial with the said longitudinal axis.

6. The apparatus of claim 1 , further comprising:
one or more additional first rings fixedly attached to said first ring, wherein each ring of said one or more additional first rings has a different diameter than said first ring and all other rings of said one or more additional first rings;
one or more additional second rings fixedly attached to said second ring, wherein each ring of said one or more additional second rings has a different diameter than said first ring and all other rings of said one or more additional second rings; and
one or more additional third rings fixedly attached to said third ring, wherein each ring of said one or more additional third rings has a different diameter than said third ring and all other rings of said one or more additional third rings.

7. An apparatus, comprising:
a rotatable cylinder having a central longitudinal axis;
means for utilizing static electrostatic forces to stabilize at least one instability of said cylinder, wherein said at least one instability is selected from the group consisting of radial, axial and tilt; and
means for utilizing magnetic forces between permanent magnets to stabilize any instability of said group that is not stabilized by said static electrostatic forces, wherein said means for utilizing static electrostatic forces to stabilize at least one instability of said cylinder comprises:
a single first ring centered on said axis, concentric with, fixedly attached to, and electrically isolated from said cylinder, said single first ring having a first diameter and comprising material selected from the group consisting of dielectric or metal;
a stationary single second ring centered on said axis, concentric with said cylinder and having a second diameter greater than said first diameter, wherein said stationary single second ring comprises metal;
a stationary single third ring centered on said axis, concentric with said cylinder and having a third diameter less than said first diameter, wherein said single third ring comprises metal, wherein said single first ring is between and spaced from said single second ring and said single third ring, wherein said single first ring and said single second ring and said single third ring are all located such that they overlap on a plane perpendicular with said central longitudinal axis; and
a power supply having a first lead and a second lead, wherein said first lead is connected to said single second ring and said second lead is connected to said single third ring.

8. The apparatus of claim 7 , wherein said first power supply is selected from a group consisting of a source of dc voltage and a source of rf voltage.

9. The apparatus of claim 7 , wherein said first ring is located above the centerline of said cylinder.

10. The apparatus of claim 7 , wherein said first ring is located above the top of said rotor.

11. The apparatus of claim 7 , wherein said first ring is attached to said cylinder with a support rod attached to said cylinder by a support structure which spans said cylinder, wherein said support rod is fixed to be coaxial with the said longitudinal axis.

12. The apparatus of claim 7 , further comprising:
one or more additional first rings electrically and fixedly attached to said first ring, wherein each ring of said one or more additional first rings has the same diameter as said first ring and all other rings of said one or more additional first rings;
one or more additional second rings electrically and fixedly attached to said second ring, wherein each ring of said one or more additional second rings has the same diameter as said second ring and all other rings of said one or more additional second rings; and
one or more additional third rings electrically and fixedly attached to said third ring, wherein each ring of said one or more additional third rings has the same diameter as said third ring and all other rings of said one or more additional third rings.

13. A method, comprising:
providing a rotatable cylinder having a central longitudinal axis;
utilizing static electrostatic forces to stabilize at least one instability of said cylinder, wherein said at least one instability is selected from the group consisting of radial, axial and tilt; and
utilizing magnetic forces between permanent magnets to stabilize any instability of said group that is not stabilized by said static electrostatic forces, wherein the step of utilizing static electrostatic forces to stabilize at least one instability of said cylinder is carried out with an apparatus comprising:
a single first ring centered on said axis, concentric with, fixedly attached to, and electrically isolated from said cylinder, said single first ring having a first diameter and comprising material selected from the group consisting of dielectric or metal;
a stationary single second ring centered on said axis, concentric with said cylinder and having a second diameter overlapping said first diameter and comprising metal;
a stationary single third ring centered on said axis, concentric with said cylinder and having a third diameter overlapping said first diameter and comprising metal, wherein said single first ring is between and spaced from said single second ring and said single third ring; and
a first power supply having a first lead and a second lead, wherein said first lead is connected to said single second ring and said second lead is connected to said single third ring, the method further comprising providing voltage from said first power supply to said second ring and said third ring.

Assignees

• L Livermore Nat Security Llc

Inventors

• Post Richard F

Classifications

• F16C32/0404 Primary

  Electrostatic bearings · CPC title

• F16C32/0408

  Passive magnetic bearings · CPC title