HEAT TRANSFER DEVICE AND ELECTRONIC DEVICE

• US 20170135247A1
• Filed: 01/26/2017
• Published: 05/11/2017
• Est. Priority Date: 09/04/2014
• Status: Abandoned Application

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Ogata, Susumu
• Application Number:
  US15/416,247
• Publication Number:
  US 20170135247A1
• Time in Patent Office: Days
• CPC Class Codes: F28D 15/025 having non-capillary condensate return means
• CPC Class Codes: H01L 23/427 Cooling by change of state, e.g. use of heat pipes by liquefied gas H01L23/445
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• 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 heat transfer device according to the disclosure includes: a heated portion; a cooled portion; a closed loop-shaped flow channel meandering from the heated portion to the cooled portion; a step that divides the flow channel at the heated portion into a first portion and a second portion, where the second portion has a smaller cross-sectional area than a cross-sectional area of the first portion; and a working fluid enclosed in the flow channel.

Claims

1. A heat transfer device comprising:

a heated portion;

a cooled portion;

a closed loop-shaped flow channel meandering from the heated portion to the cooled portion;

a step that divides the flow channel at the heated portion into a first portion and a second portion, where the second portion has a smaller cross-sectional area than a cross-sectional area of the first portion; and

a working fluid enclosed in the flow channel.

2. The heat transfer device according to claim 1, wherein the first portion at the heated portion is longer than the second portion at the heated portion.

3. The heat transfer device according to claim 2, wherein

the flow channel at the heated portion includes a bent portion that is bent into a U-shape, and

the step is located at a position away from a peak of the bent portion.

4. The heat transfer device according to claim 1, wherein the cross-sectional area of the second portion is equal to or greater than 0.6 times but equal to or below 1.0 times as large as the cross-sectional area of the first portion.

5. The heat transfer device according to claim 1, wherein a height of the flow channel at the first portion is higher than a height of the flow channel at the second portion.

6. The heat transfer device according to claim 1, wherein the first portion occupies all of the flow channel at the cooled portion.

7. The heat transfer device according to claim 1, wherein an inclined portion inclined from the first portion toward the second portion is provided on an inner surface of the flow channel.

8. The heat transfer device according to claim 1, further comprising:

a sheet having a surface with which the flow channel is provided, wherein

the sheet below the flow channel includes a thin portion located on a lower side with respect to the step and having a first thickness, and

a thick portion located on an upper side with respect to the step and having a second thickness thicker than the first thickness.

9. An electronic device comprising:

a heat transfer device including a heated portion and a cooled portion; and

an electronic component thermally connected to the heated portion of the heat transfer device, wherein

the heat transfer device includes

a closed loop-shaped flow channel meandering from the heated portion to the cooled portion,

a step that divides the flow channel at the heated portion into a first portion and a second portion, where the second portion has a smaller cross-sectional area than a cross-sectional area of the first portion; and

a working fluid enclosed in the flow channel.

10. The electronic device according to claim 9, wherein the heat transfer device serves as a housing that houses the electronic component.