METAL ENCASED GRAPHITE LAYER HEAT PIPE

• US 20160212888A1
• Filed: 01/20/2015
• Published: 07/21/2016
• Est. Priority Date: 01/20/2015
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Inventors: Nikkhoo, Michael, Hurbi, Erin
• Granted Patent: US 10,028,418 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G02B 2027/0178 Eyeglass type eyeglass details G02C
• CPC Class Codes: G02B 27/0176 characterised by mechanical features
• CPC Class Codes: G02B 7/008 with means for compensating for changes in temperature or for controlling the temperature; thermal stabilisation
• CPC Class Codes: H05K 7/20963 Heat transfer by conduction from internal heat source to heat radiating structure H05K7/20972 takes precedence

Abstract

A metal encased multilayer stack of graphite sheets used as a passive thermal conductor. In the stack, each sheet has a plane high thermal conductivity along a first axis and a plane of lower thermal conductivity along a second axis. The stack is created to have a three-dimensional shape including a length and a width, and the first axis is aligned parallel to said length, the multilayer stack having a height less than the width. A first metal structure surrounds the multilayer stack of graphite sheets, with the metal structure encasing the multilayer stack along the length, width and height of the multilayer stack.

Claims

1. An apparatus comprising:

a multilayer stack of graphite sheets, each sheet having a plane high thermal conductivity along a first axis and a plane of lower thermal conductivity along a second axis, the stack having a three-dimensional shape including a length and a width, and the first axis is aligned parallel to said length, the multilayer stack having a height less than the width;

a first metal structure surrounding the multilayer stack of graphite sheets, the metal structure encasing the multilayer stack along the length, width and height of the multilayer stack.

2. The apparatus of claim 1 wherein the stack is comprised of a plurality of sheets of pyrolytic graphite.

3. The apparatus of claim 1 wherein the metal is selected from one of:

aluminum, copper, silver, aluminum alloy, copper alloy, and silver alloy.

4. The apparatus of claim 1 wherein an uppermost layer in the stack and a lowermost later in the stack contact a respective upper and lower surface of the metal encasing layer.

5. The apparatus of claim 1 further including a second multilayer stack and second metal encasing structure, the second metal encasing structure bonded to the first metal encasing structure by a thermally transmissive material.

6. The apparatus of claim 1 wherein stack comprises a plurality of graphite sheets, each sheet bonded to a respective sheet using an adhesive.

7. The apparatus of claim 1 wherein the stack comprises a plurality of graphite sheets in direct mutual contact.

8. The apparatus of claim 7 wherein the metal structure creates a hermetic vacuum around the multilayer stack.

9. A wearable device including electronic components, comprising:

a mounting structure including the electronic components; and

a metal encased multilayer stack of a plurality graphite sheets and thermally bonded to the electronic components, each sheet having a plane high thermal conductivity along a first axis and a lower thermal conductivity along a second axis, the stack having a three-dimensional shape including a length and a width and the first axis aligns parallel to said length, the multilayer stack having a height less than the width, the metal encasing the multilayer stack along the length, width and height of the multilayer stack.

10. The wearable device of claim 9 wherein the stack is comprised of a plurality of sheets of pyrolytic graphite.

11. The wearable device of claim 10 wherein the metal is selected from one of:

aluminum, copper, silver, aluminum alloy, copper alloy, and silver alloy.

12. The wearable device of claim 11 wherein an uppermost layer in the stack and a lowermost later in the stack contact a respective upper and lower surface of the metal encasing layer.

13. The wearable device of claim 12 further including a second multilayer stack and second metal encasing the second multilayer stack, the second metal bonded to the first metal by a thermally transmissive material.

14. The wearable device of claim 12 wherein each sheet bonded to a respective sheet using an adhesive.

15. The wearable device of claim 12 wherein the stack comprises a plurality of graphite sheets in direct mutual contact.

16. The wearable device of claim 15 wherein the first metal encases the stack to create a hermetic vacuum around the multilayer stack.

17. A head mounted display including control circuits which produce heat, comprising:

an optical mounting structure including the heat producing electrical components, the mounting structure housing display optical system coupled to the heat producing electrical components, and first and second temple arms extending away from the heat producing electrical components and the display optical systems; and

a metal encased multilayer stack of graphite sheets and thermally bonded to the heat producing electrical components and to an exterior surface of the optical mounting structure, each sheet having a plane high thermal conductivity along a first axis and a lower thermal conductivity along a second axis, the stack having a three-dimensional shape including a length and a width and the first axis aligns parallel to said length, the multilayer stack having a height less than the width, the metal structure encasing the multilayer stack along the length, width and height of the multilayer stack.

18. The head mounted display of claim 17 wherein an uppermost layer in the stack and a lowermost later in the stack contact a respective upper and lower surface of the metal encasing layer.

19. The head mounted display of claim 18 wherein the stack is comprised of a plurality of sheets of pyrolytic graphite.

20. The head mounted display of claim 19 wherein the stack comprises a plurality of graphite sheets in direct mutual contact.