X-ray tubes and methods of making the same

• US 20080056450A1
• Filed: 09/01/2006
• Published: 03/06/2008
• Est. Priority Date: 09/01/2006
• Status: Abandoned Application

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Rouzou, Isabelle Berangere, Joshi, Prasad, Lemarchand, Gwenael, Sampath, Srinidhi
• Application Number:
  US11/514,417
• Publication Number:
  US 20080056450A1
• Time in Patent Office: Days
• US Class Current: 378/132
• CPC Class Codes: H01J 2235/1046 Bearings and bearing contact surfaces
• CPC Class Codes: H01J 2235/1086 liquid metals
• CPC Class Codes: H01J 2235/1208 of the bearing assembly
• CPC Class Codes: H01J 2235/1295 Contact between conducting bodies
• CPC Class Codes: H01J 35/1024 Rolling bearings

Abstract

A rolling contact bearing assembly is provided. The bearing assembly includes an inner ring and an outer ring concentrically disposed about the inner ring. The bearing assembly further includes a plurality of rolling contact elements disposed between the inner and outer rings, where at least one of the inner ring, the outer ring and the rolling elements having a solid lubricant coating disposed thereon. The bearing assembly further includes a gallium-based cooling solution disposed between the inner and outer rings and in contact with the rolling contact elements.

Claims

1. A rolling contact bearing assembly, comprising:

an inner ring;

an outer ring disposed concentrically about the inner ring;

a plurality of rolling contact elements disposed between the inner and outer rings, at least one of the inner ring, the outer ring and the rolling elements having a solid lubricant coating disposed thereon; and

a gallium-based cooling solution disposed between the inner and outer rings and in contact with the rolling contact elements.

2. The rolling contact bearing assembly of claim 1, the gallium-based cooling solution comprising an alloy of indium, tin, or a combination thereof.

3. The rolling contact bearing assembly of claim 1, wherein the solid lubricant coating comprises two or more coatings.

4. The rolling contact bearing assembly of claim 1, wherein the solid lubricant coating is chemically resistant to the gallium-based cooling solution.

5. The rolling contact bearing assembly of claim 1, the solid lubricant coating comprising molybdenum, tantalum, vanadium, cobalt, or a combination thereof.

6. The rolling contact bearing assembly of claim 1, the solid lubricant coating comprising nitrides of titanium, chromium, tantalum, vanadium, boron, titanium-aluminum, titanium-carbon, aluminum-chromium, or a combination thereof.

7. The rolling contact bearing assembly of claim 1, the solid lubricant coating comprising di-chalcogenides of molybdenum, niobium, tungsten, or a combination thereof.

9. The rolling contact bearing assembly of claim 1, wherein a thickness of the solid lubricant coating is in a range from about 100 nanometers to about 1500 nanometers.

10. The rolling contact bearing assembly of claim 1, wherein the gallium-based cooling solution contacts the inner and outer rings to transfer heat between the rings.

11. The rolling contact bearing assembly of claim 1, wherein the inner and outer rings have a temperature difference in a range from about 100°

C. to about 150°

C.

12. The rolling contact bearing assembly of claim 1, wherein the bearing comprises a radial contact ball bearing or an angular contact ball bearing.

8. The rolling contact bearing assembly of claim 8, wherein the di-chalcogenides are doped by titanium.

13. A rotating anode assembly for use in an X-ray tube, comprising:

a shaft configured to rotate the rotating anode assembly;

a rolling contact bearing assembly disposed about the shaft, the rolling contact bearing assembly comprising;

an inner ring;

an outer ring disposed concentrically about the inner ring;

a plurality of rolling contact elements disposed between the inner and outer rings, at least one of the inner ring, the outer ring or the rolling elements having a solid lubricant coating disposed thereon; and

a cooling solution comprising gallium disposed between inner and outer rings and in contact with the rolling contact elements.

14. The anode assembly of claim 13, wherein the coefficient of friction of the solid lubrication coating is in a range from about 0.02 to about 0.3.

15. The anode assembly of claim 13, wherein the cooling solution comprises gallium.

16. An X-ray tube for generating X-rays, the X-ray tube comprising:

a rotating anode;

a shaft supporting the anode; and

an anti-friction bearing assembly supporting the shaft in rotation, the anti-friction bearing assembly comprising;

a plurality of anti-friction elements disposed in an housing formed by inner and outer bearing rings, wherein at least one of the outer ring, the inner ring, or the plurality of anti-friction elements comprises a lubricant coating disposed thereon; and

a thermal dissipation medium disposed between and in contact with the inner and outer rings, wherein the thermal dissipation medium comprises a gallium-based coolant.

17. The X-ray tube of claim 16, comprising two anti-friction bearing assemblies disposed at a distance from one another along the shaft.

18. The X-ray tube of claim 16, further comprising a thermal compensation element disposed about the shaft.

19. The X-ray tube of claim 16, wherein the lubricant coating comprises two or more coatings.

20. The X-ray tube of claim 16, wherein the lubricant coating is chemically resistant to the gallium-based cooling solution.