GRAPHITE THERMAL CONDUIT SPRING

• US 20190317572A1
• Filed: 04/13/2018
• Published: 10/17/2019
• Est. Priority Date: 04/13/2018
• Status: Active Grant

• Current Assignee: Dell Products LP (Dell Technologies Inc.)
• Original Assignee: Dell Products LP (Dell Technologies Inc.)
• Inventors: North, Travis C., Schwager, Mark A., Shelnutt, Austin M., Morrison, John T.
• Granted Patent: US 10,579,113 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 1/1616 with folding flat displays, e.g. laptop computers or notebooks having a clamshell configuration, with body parts pivoting to an open position around an axis parallel to the plane they define in closed position
• CPC Class Codes: G06F 1/1681 Details related solely to hinges hinge details related to the transmission of signals or power are classified in G06F1/1683
• CPC Class Codes: G06F 1/203 for portable computers, e.g. for laptops
• CPC Class Codes: G06F 1/206 comprising thermal management
• CPC Class Codes: G06F 2200/1634 Integrated protective display lid, e.g. for touch-sensitive display in handheld computer
• CPC Class Codes: G06F 2200/201 Cooling arrangements using cooling fluid
• CPC Class Codes: G06F 2200/202 Air convective hinge
• CPC Class Codes: G06F 2200/203 Heat conductive hinge
• CPC Class Codes: H05K 7/20327 Accessories for moving fluid, for connecting fluid conduits, for distributing fluid or for preventing leakage, e.g. pumps, tanks or manifolds
• CPC Class Codes: H05K 7/20336 Heat pipes, e.g. wicks or capillary pumps

Abstract

A portable information handling system transfers thermal energy associated with operation of processing components in a main housing portion through a graphite torsion spring formed from a graphite sheet by cutting arms to extend out of opposing corners of a central portion and rolling the central portion about a central axis. The graphite torsion spring passes thermal energy between the housing portions with the spring releasing tension as the housing portions rotate from a closed to an open position and the central axis disposed about a hinge pin that couples the housing portions to each other.

Claims

1. An information handling system comprising:

a main housing portion;

a lid housing portion;

one or more hinges rotationally coupling the main housing portion and the lid housing portion;

plural processing components disposed in the main housing portion and operable to process information;

a display disposed in the lid housing portion and interfaced with the processing components to present the information as visual images;

a thermal sink thermally coupled to one or more of the plural processing components, the thermal sink operable to absorb thermal energy of the one or more processing components;

a thermal exchanger disposed in the lid housing portion and operable to reject the thermal energy to an external environment; and

a thermal conduit extending from the thermal sink to the thermal exchanger to conduct the thermal energy from the thermal sink to the thermal exchanger, the thermal conduit comprising a contiguous graphite sheet cut to have first and second arms extending from a central portion, the first and second arms offset on opposite sides of the central portion, the central portion rolled into a circular configuration to form a torsion spring.

2. The information handling system of claim 1 further comprising:

a hinge rotationally coupling the main and lid housing portions, the hinge having a pin coupled between first and second supports;

wherein the pin passes through the rolled central portion.

3. The information handling system of claim 2 wherein the thermal conduit contiguous graphite sheet includes a spreader portion extending from the first arm and into the lid housing portion, the spreader portion substantially the same size as the lid housing portion.

4. The information handling system of claim 3 wherein the thermal exchanger comprises a copper film integrated into a perimeter of the lid housing portion, the copper film coupled to the lid housing portion and the graphite sheet spreader portion, the lid housing portion rejecting the thermal energy from an outer surface.

5. The information handling system of claim 4 wherein the thermal sink comprises a heat sink coupled to a processor and the thermal conduit second arm couples to the heat sink.

6. The information handling system of claim 1 wherein the thermal conduit comprises plural layers of vertically stacked graphite sheets coupled together.

7. The information handling system of claim 6 wherein each of the plural graphite sheets terminates separately at the first and second arms, each sheet independently coupled to thermal sink and thermal exchanger.

8. The information handling system of claim 1 further comprising:

a second thermal conduit extending from the thermal sink to the thermal exchanger to conduct the thermal energy from the thermal sink to the thermal exchanger, the second thermal conduit comprising a contiguous graphite sheet cut to have first and second arms extending from a central portion, the first and second arms offset on opposite sides of the central portion, the central portion rolled into a circular configuration to form a torsion spring;

wherein the thermal conduits roll in opposite directions.

9. The information handling system of claim 8 wherein the both thermal conduits relax their torsion spring at rotation from a closed orientation of the lid and main housing portions towards an open orientation.

10. A method for transferring thermal energy between rotationally coupled information handling system housing portions, the method comprising:

cutting a sheet of graphite to have first and second arms extending from opposite sides of a central portion;

rolling the central portion to align the first and second arms extending out of a torsion spring;

coupling the first arm to a first of the rotationally coupled housing portions;

coupling the second arm to a second of the rotationally coupled housing portions; and

transferring the thermal energy from the first to the second housing portions through the graphite sheet.

11. The method of claim 10 further comprising:

coupling the first arm to a vapor chamber of the first of the rotationally coupled housing portions; and

controlling pressure within the vapor chamber to selectively transfer the thermal energy from the second to the first housing portion.

12. The method of claim 10 further comprising:

cutting the sheet of graphite to have a spreader portion extending from the first arm into a first of the rotationally coupled housing portions, the spreader portion having a perimeter of substantially a perimeter of the first housing portion; and

transferring the thermal energy from the spreader to a copper film integrated with the first housing portion.

13. The method of claim 10 further comprising:

cutting plural sheets of graphite to have the first and second arms extending from the opposite sides of the central portion at each sheet;

vertically stacking the plural sheets of graphite to form a composite thermal conduit; and

coupling each of the plural sheets individually to the first and second housing portions.

14. The method of claim 13 wherein the rolling further comprises rolling the vertically stacked sheets of graphite to release the spring with rotation of the housing portions from a closed configuration to an open configuration.

15. The method of claim 13 wherein coupling the first arm to a first of the rotationally coupled housing portions further comprises:

coupling each sheet of graphite independently to a different location of a heat sink; and

coupling the heat sink to a processor.

16. The method of claim 10 further comprising:

rotationally coupling the housing portions with a hinge having a pin; and

disposing the center portion around the pin.

17. A system for thermal management of a portable information handling system, the system comprising:

a first thermal device configured to couple to a processor in a main housing portion, the first thermal device absorbing thermal energy from the processor;

a second thermal device distal the first thermal device and configured to reject the thermal energy; and

a graphite torsion spring formed from a graphite sheet having first and second arms extending from opposing corners of a rectangular center portion, the rectangular center portion rolled about a central axis, thermal energy of the processor transferred through the graphite sheet to the second thermal device.

18. The system of claim 17 wherein the second thermal device comprises a vapor chamber configured to couple in a lid housing portion proximate a display and the first thermal device comprises a heat sink configured to couple to the processor in the main housing portion.

19. The system of claim 18 wherein the second thermal device comprises a vapor chamber coupled to the second graphite sheet arm, the system further comprising a controller operable to adapt a pressure of the vapor chamber to reverse the transfer direction of the thermal energy.

20. The system of claim 17 wherein graphite torsion spring further comprises plural graphite sheets layered into a composite with adhesive, each graphite sheet independently coupled to each of the first and second thermal devices.