Heat management device and method of manufacture

Patent metadata

Field	Value
Publication number	US-11076510-B2
Application number	US-201816102435-A
Country	US
Kind code	B2
Filing date	Aug 13, 2018
Priority date	Aug 13, 2018
Publication date	Jul 27, 2021
Grant date	Jul 27, 2021

Abstract

A heat-management device includes an array of recesses distributed across an external surface of a thermally conductive body. The device includes an array of protrusions interspersed with the array of recesses that form a network of cavities within an internal volume of the thermally conductive body. The array of recesses and the array of protrusions define a non-planar interface that is complementary to a curved surface of a heat source. A fluid volume can be retained within the network of cavities at a pressure lower than atmospheric pressure. The heat management device includes a cooling operation mode wherein the fluid volume absorbs heat from the heat source through the non-planar interface and dissipates heat away from the heat source through the network of cavities.

First claim

What is claimed is:

1. A heat-management device comprising:
an array of recesses distributed across a first external surface of a thermally conductive body, at least a portion of the thermally conductive body being composed of a metal, and the portion of the thermally conductive body having been formed using a 3 dimensional metal printing process;
an array of protrusions interspersed with the array of recesses and forming a network of cavities within an internal volume of the thermally conductive body, the array of recesses and the array of protrusions defining a non-planar interface that is configured to be coupled to a curved surface of a heat source and the non-planar interface has a curvature that is matched to fit the curved surface of the heat source; and
wherein a volume of fluid is retained within the network of cavities, the volume of fluid absorbs heat from the heat source through the non-planar interface and dissipates heat away from the heat source through the network of cavities.

2. The heat-management device of claim 1 , wherein the the printable metal comprises at least one of a material including titanium, a material including tungsten, and a material including steel.

3. The heat-management device of claim 1 , wherein the array of recesses and the array of protrusions comprise curved edges.

4. The heat-management device of claim 1 , wherein the thermally conductive body is mounted to the heat source and provides structural support to the heat source.

5. The heat-management device of claim 1 , wherein the thermally conductive body includes a second external surface that is opposite the first external surface, and the array of recesses is distributed across the second external surface, and wherein the network of cavities forms a lattice network of channels.

6. The heat-management device of claim 5 , wherein the lattice network of channels provides the thermally conductive body with a structural stiffness resistant to deformation.

7. The heat-management device of claim 1 , wherein in a flushing operation state, the thermally conductive body comprises a pair of ports that transmit metal powder from within the internal volume, and wherein in a sealing operation state, a first port of the pair of ports is sealed and a second port of the pair of ports facilitates depressurization and transmission of the volume of fluid into the internal volume.

8. The heat-management device of claim 1 , wherein external surfaces of the thermally conductive body comprise a surface sealing treatment comprising at least one of an epoxy coating and particle impregnation.

9. The heat-management device of claim 1 , wherein the heat source is a component of a head-mounted display, and wherein the curved surface comprises a curved surface of a face plate of the head-mounted display.

10. The heat-management device of claim 1 , wherein some recesses of the array of recesses each include a respective opening, and each channel allows air to flow through the opening between the first external surface and a second external surface of the thermally conductive body.

11. The heat-management device of claim 10 , further comprising a fan that blows air through each of the openings.

12. The heat-management device of claim 1 , wherein a wall between a cavity of the network of cavities and the first external surface is at most 200 microns thick.

13. The heat-management device of claim 1 , wherein the network of cavities comprises a first layer of channels at a first depth within the thermally conductive body and a second layer of channels at a second depth within the thermally conductive body.

14. The heat-management device of claim 1 , wherein the volume of fluid in a liquid state absorbs heat from the heat source through the non-planar interface, undergoes a phase transition to a gas state, returns to the liquid state upon dissipating heat away from the heat source, and travels back toward the non-planar interface through the network of cavities.

15. The heat-management device of claim 1 , wherein the volume of fluid is retained within the network of cavities at a pressure lower than atmospheric pressure.

16. The heat-management device of claim 1 , wherein the non-planar interface provides coverage of a portion of the curved surface of the heat source.

17. A method comprising:
forming a thermally conductive body, at least a portion of the thermally conductive body being composed a metal, and the portion of the thermally conductive body was formed using a 3 dimensional printing process, the thermally conductive body including:
an array of recesses distributed across a first external surface of the thermally conductive body; and
an array of protrusions interspersed with the array of recesses and defining a network of cavities within an internal volume of the thermally conductive body, the array of recesses and the array of protrusions defining a non-planar interface configured to be coupled to a curved surface of a heat source and the non-planar interface has a curvature that is matched to fit the curved surface of the heat source; and

retaining a volume of fluid within the network of cavities, and the volume of fluid absorbs heat from the heat source through the non-planar interface and dissipates heat away from the heat source through the network of cavities.

18. The method of claim 17 , wherein forming the thermally conductive body comprises generating data defining the morphology of a body that comprises the array of recesses and the array of protrusions.

19. The method of claim 18 , wherein forming the thermally conductive body further comprises transforming the data into parameters of a set of cross sections of the body, and for each of the set of cross sections of the body:
adjusting the height of a print bed substrate, the height corresponding to the cross section of the body,
depositing powdered metal material in a uniform layer across the print bed substrate, and
bonding, using a laser, powdered metal material of the uniform layer to a running build of the body, based upon the cross section.

20. The method of claim 19 , further comprising sealing surface imperfections of the thermally conductive body upon performing at least one of: dipping external surfaces of the thermally conductive body in an epoxy material and applying an impregnation process to external surfaces of the thermally conductive body.

21. The method of claim 19 , further comprising: by way of the pair of ports, transmitting metal powder from within the internal volume of the thermally conductive body with a flushing operation, sealing a first port of the pair of ports, and transmitting the volume of fluid into the network of cavities at a pressure lower than atmospheric pressure through a second port of the pair of ports.

22. A system comprising:
a heat management device coupled to one or more heat-generating surfaces of a head-mounted display, and the one or more heat-generating surfaces includes at least one curved surface, the heat management device comprising:
an array of recesses distributed across a first external surface of a thermally conductive body, at least a portion of the thermally conductive body being composed of a metal, and the portion of the thermally conductive body having been formed using a 3 dimensional metal printing process,
an array of protrusions interspersed with the array of recesses and forming a network of cavities within an internal volume of the thermally conductive body, the array of recesses and

Assignees

• Facebook Tech Llc

Inventors

• Stellman Jeffrey Taylor

Classifications

• G06F2200/201

  Cooling arrangements using cooling fluid · CPC title

• B23P15/26

  heat exchangers {or the like (making heat exchangers by methods covered by other subclasses B21D53/02)} · CPC title

• G06F1/1637

  Details related to the display arrangement, including those related to the mounting of the display in the housing · CPC title

• G06F1/163

  Wearable computers, e.g. on a belt · CPC title

• G02B27/0176 Primary

  characterised by mechanical features · CPC title