Vacuum assemblies and methods of formation

Patent metadata

Field	Value
Publication number	US-9831058-B2
Application number	US-201514601427-A
Country	US
Kind code	B2
Filing date	Jan 21, 2015
Priority date	Jan 21, 2015
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

The disclosed subject matter includes devices and methods relating to vacuums and vacuum assemblies. In some aspects, methods and devices relate to a vacuum assembly including a body defining an evacuated vacuum chamber, a conduit in the body extending between the vacuum chamber and an exterior of the body, a plug at least partially occluding the conduit, and a seal between the plug and the body that seals the vacuum chamber from the exterior of the body.

First claim

What is claimed is:

1. A method for forming a vacuum in a vacuum assembly for an X-ray device, the method comprising:
providing the vacuum assembly defining an internal vacuum chamber in fluid communication with an exterior of the vacuum assembly via a conduit in the vacuum assembly between the vacuum chamber and the exterior of the vacuum assembly;
positioning a plug to at least partially occlude the conduit such that at least one space between the plug and the vacuum assembly permits fluid to travel between the vacuum chamber and the exterior of the vacuum assembly;
evacuating the vacuum chamber so that gas in the vacuum chamber exits the vacuum chamber through the at least one space between the plug and the vacuum assembly;
positioning the plug further into the conduit; and
sealing the evacuated vacuum chamber with the plug such that the vacuum chamber is sealed from the exterior of the vacuum assembly.

2. The method of claim 1 , further comprising assembling at least a portion of the vacuum assembly in a clean room environment prior to positioning the plug to at least partially occlude the conduit.

3. The method of claim 2 , further comprising removing contaminants from at least a portion of the vacuum assembly in the clean room environment prior to positioning the plug to at least partially occlude the conduit.

4. The method of claim 3 , further comprising positioning the plug to at least partially occlude the conduit in a clean room environment.

5. The method of claim 1 , further comprising positioning the plug so that at least one interface member is positioned at an interface between the plug and the vacuum assembly.

6. The method of claim 5 , wherein the at least one interface member includes a meltable material configured to form a bond between the plug and the vacuum assembly, the method further comprising heating to melt the material.

7. The method of claim 6 , wherein the meltable material is a braze alloy and the sealing further comprises:
brazing the plug and the vacuum assembly with the braze alloy; and
cooling at least a portion of the plug and the vacuum assembly to form a braze seal from the braze alloy between the plug and the vacuum assembly.

8. The method of claim 7 , wherein the plug includes a shoulder and the conduit includes a taper between a narrower conduit portion and a wider conduit portion, the taper configured to interface with the shoulder, the method further comprising positioning the plug at least partially inside of the conduit such that the shoulder interfaces with the taper.

9. The method of claim 1 , wherein the plug is spherical and the conduit includes a taper between a narrower conduit portion and a wider conduit portion, the taper configured to interface with the plug, the method further comprising positioning the plug at least partially inside of the conduit such that the plug interfaces with the taper.

10. The method of claim 1 , wherein at least a portion of the plug includes a first material and at least a portion of the vacuum assembly that defines the conduit includes a second material with greater thermal expansion characteristics than the first material, further comprising heating such that the conduit expands more relative to the plug.

11. The method of claim 10 , wherein the plug includes a dimension greater than a cross-sectional dimension of the conduit before heating and the heating expands the cross-sectional dimension more relative to the plug such that the plug may be positioned further into the conduit, further comprising positioning the plug further into the conduit.

12. The method of claim 11 , the sealing of the vacuum chamber further comprising cooling at least a portion of the plug and the vacuum assembly such that the conduit contracts more relative to the plug.

13. The method of claim 12 , the sealing of the vacuum chamber further comprising forming a diffusion bond at an interface of the plug and the vacuum assembly.

14. The method of claim 1 , wherein the plug includes a plug body and a coating that surrounds at least a portion of the plug body, the coating including one or more of the following: a material suitable for forming diffusion bonds with the vacuum assembly and/or a material configured to contribute to decreasing friction between at least on wall of the conduit and a surface of the plug.

15. The method of claim 1 , further comprising positioning a getter within the vacuum chamber and activating the getter.

16. The method of claim 1 , further comprising positioning the vacuum assembly inside of a vacuum furnace before evacuating the vacuum chamber, wherein the vacuum furnace evacuates the vacuum chamber and heats at least a portion of the plug or the vacuum assembly.

17. An X-ray assembly comprising:
an anode;
a body, wherein the anode and the body define an evacuated vacuum chamber;
a conduit extending through the anode between the interior of the vacuum chamber and an exterior of the vacuum chamber;
a plug coupled to the anode to at least partially occlude the conduit; and
a seal between the plug and the anode that seals the vacuum chamber from the exterior of the vacuum chamber.

18. The X-ray assembly of claim 17 , wherein the seal is a braze seal formed of a braze alloy melted to form a bond between the plug and the anode.

19. The X-ray assembly of claim 17 , wherein at least a portion of the plug includes a first material, at least a portion of the anode includes a second material with greater thermal expansion characteristics than the first material, and the seal is a diffusion bond formed at an interface of the plug and the anode.

20. The X-ray assembly of claim 17 , wherein the anode includes a target defining an X-ray emission face;
further comprising:
a cathode assembly that defines an electron emission face and includes an electron emitter configured to emit electrons when energized; and
an X-ray emission window positioned at an end of the X-ray assembly;
wherein the vacuum assembly surrounds at least a portion of the anode and the cathode assembly within the vacuum chamber.

Assignees

• Varex Imaging Corp

Inventors

• Smith David Craig
• Price Christopher
• Bullock Derek
• Burke James E

Classifications

• H01J5/22 Primary

  Vacuum-tight joints between parts of vessel · CPC title

• H01J35/16

  Vessels; Containers; Shields associated therewith · CPC title

• H01J9/385

  Exhausting vessels · CPC title

• H01J2209/26

  Sealing parts of the vessel to provide a vacuum enclosure · CPC title

• H01J7/18

  Means for absorbing or adsorbing gas, e.g. by gettering · CPC title