US20100155030A1

US20100155030A1 - Thermal module

Info

Publication number: US20100155030A1
Application number: US12/485,942
Authority: US
Inventors: Ching-Bai Hwang; Jin-Gong Meng; Zhi-Hui Zhao
Original assignee: Furui Precise Component Kunshan Co Ltd; Foxconn Technology Co Ltd
Current assignee: Furui Precise Component Kunshan Co Ltd; Foxconn Technology Co Ltd
Priority date: 2008-12-23
Filing date: 2009-06-17
Publication date: 2010-06-24
Also published as: CN101765352A; CN101765352B

Abstract

A thermal module includes a blower, a fin unit and a heat pipe. The blower includes a housing and an impeller received in the housing. The housing defines an air inlet and an air outlet perpendicular to the air inlet. The fin unit is arranged at the air outlet of the blower. The heat pipe includes a tube defining a chamber, and a wick structure disposed in the chamber. The heat pipe forms an evaporation section and a condensation section attaching to the fin unit. At least one contacting member is depressed inwardly from the evaporation section of the heat pipe for accommodating an electronic component therein. A depth of the chamber at the at least one contacting member is less than that at other portion of the evaporation section of the heat pipe without the at least one contacting member.

Description

BACKGROUND

1. Technical Field
The disclosure generally relates to thermal modules, and more particularly to a thermal module incorporating a plate type heat pipe.
2. Description of Related Art
With continuing development of the electronic technology, electronic components such as CPUs are generating more and more heat which is required to be dissipated immediately. A thermal module is usually adopted for cooling the electronic component.
Generally, the thermal module includes a blower for generating forced airflow, a fin unit arranged at an air outlet of the blower, and a heat pipe. The heat pipe includes an evaporating section attached to the electronic component to absorb heat therefrom, and a condensing section attached to the fin unit to transfer the heat of the electronic component to the fin unit. Thus the forced airflow of the blower can take away the heat after flows through the fin unit. However, most of electronic devices that contain electronic components therein, such as a laptop computer, do not have enough space therein, and thus a size of the heat pipe is usually limited. Accordingly, a heat transfer capability of the heat pipe is limited, which means that the heat of the electronic component can not be timely transferred to the fin unit for dissipation.
For the foregoing reasons, therefore, there is a need in the art for a thermal module which overcomes the limitations described.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric, assembled view of a thermal module according to an exemplary embodiment.

FIG. 2 is an isometric, exploded view of the thermal module of FIG. 1.

FIG. 3 is a cross sectional view showing the thermal module of FIG. 1 assembled onto an electronic component.

FIG. 4 is similar to FIG. 3, but shows a thermal module with an alternative heat pipe.

DETAILED DESCRIPTION

Referring to FIGS. 1 and 3, a thermal module for cooling plural electronic components 90 which are mounted on a circuit board 80 of an electronic device is shown, including a blower 10, a fin unit 20 and a heat pipe 30. In FIG. 3, although only one electronic component 90 is shown for simplifying the drawings, it is to be understood that other electronic components 90 not shown in FIG. 3 can be assembled to the thermal module in the same way for cooling.
Referring to FIG. 2, the blower 10 is for generating forced airflow, and includes a fan housing 12 and an impeller 14 rotatably received in the fan housing 12. A circular air inlet 120 is defined in a top side of the fan housing 12. An air outlet 122 is defined in a lateral side of the fan housing 12. The air outlet 122 is rectangular, and is perpendicular to the air inlet 120. The fin unit 20 is arranged at the air outlet 122 of the blower 10. The fin unit 20 includes a plurality of fins 22 stacked together. A channel 24 is defined between neighboring fins 22 and communicates with the air outlet 122.
The heat pipe 30 is in plate type, and has a profile substantially being Z-shaped. The heat pipe 30 forms an evaporation section 31 and a condensation section 33 at two ends thereof, respectively. The evaporation section 31 is attached to the electronic components 90 to absorb heat therefrom. The condensation section 33 is linear-shaped, and attaches to the fin unit 20. The heat of the electronic components thus can be transferred to the fin unit 20 by the heat pipe 30 for dissipation.
The evaporation section 31 of the heat pipe 30 is substantially L-shaped, and includes an elongated portion 312 extending perpendicularly from an end of the condensation section 33, and an end portion 314 extending perpendicularly from the elongated portion 312. The end portion 314 is parallel to the condensation section 33. The end portion 314 and the condensation section 33 are respectively located at opposite sides and opposite ends of the elongated portion 312 of the heat pipe 30. A plurality of through holes 38 are defined in the evaporation section 31 of the heat pipe 30 for fixing members, such as screws to extend therethrough and be secured to the circuit board 80, thus to assemble the thermal module onto the electronic components 90.
Referring to FIG. 3, the heat pipe 30 includes a sealed tube 37, a wick structure 39 and a working fluid. The tube 37 is made of metal with high heat conductivity coefficient, such as copper or its alloy. The tube 37 includes a top plate 36, a bottom plate 32 and a side plate 34 interconnecting outer peripheries of the top plate 36 and the bottom plate 32. Cooperatively the top plate 36, the bottom plate 32 and the side plate 34 define a vacuum chamber 35 in the tube 37. The working fluid is filled in the chamber 35, and has a relatively lower pressure and boiling point. The wick structure 39 is disposed in the chamber 35 of the heat pipe 30 soaked with the working fluid. A plurality of pores are defined in the wick structure 39 to generate a capillary force to the working fluid.
Referring to FIG. 2 again, the top plate 36 of the heat pipe 30 includes three portions, i.e., a first portion 330 at the condensation section 33 of the heat pipe 30, a second portion 369 at the elongated portion 312 of the evaporation section 31, and a third portion 367 at the end portion 314 of the evaporation section 31. The first portion 330 is planar and attaches to a bottom side of the fin unit 20 closely, whilst the second portion 369 and the third portion 367 of the top plate 36 are used to contact the electronic components 90.
The second portion 369 and the third portion 367 of the top plate 36 form a plurality of contacting members 360 depressed downwardly therefrom for accommodating the electronic components 90 therein. Shapes, sizes, and positions of the contacting members 360 are decided according to an arrangement of the electronic components 90. The plurality of contacting members 360 can have different shapes, areas and depths. In this embodiment, four separated contacting members 360 are shown, in which one contacting member 360 is defined in the third portion 367 of the top plate 36, i.e., at the end portion 314 of the evaporation section 31, and the other three contacting members 360 are defined in the second portion 369 of the top plate 36, i.e., at the elongated portion 312 of the evaporation section 31. Thus the heat pipe 30 can be used to absorb heat from four electronic components 90 at the same time.
Each contacting member 360 is located at a middle of the top plate 36, with a width smaller than that of the evaporation section 31 of the heat pipe 30. Two opposite lateral sides, i.e., left and right sides of each contacting member 360 respectively space a distance from the side plate 34 of the tube 37 of the heat pipe 30. Each of the contacting members 360 includes a base 361 and a flange 362 around the base 361. The base 361 is substantially square or rectangular, and is lower than the top plate 36 of the heat pipe 30. The flange 362 is perpendicular to the base 361, and connects the base 361 to the top plate 36 of the heat pipe 30. A concave 363 is defined in the top plate 36 above each base 361 and surrounded by a corresponding flange 362. Thus, a depth of the chamber 35 of the heat pipe 30 at the contacting members 360 is less than that at other portion of the evaporation section 31 of the heat pipe 30 without the contacting members 360.
In this embodiment, the wick structure 39 is sintered powders. The wick structure 39 is arranged in the middle of the chamber 35 of the heat pipe 30. A width of the wick structure 39 is smaller than that of the heat pipe 30, but larger than that of each of the contacting members 360. The wick structure 39 includes a planar bottom side attaching to the bottom plate 32 of the tube 37 of the heat pipe 30, and a non-planar top side attaching to the top plate 36 of the tube 37. Four recesses are defined in the top side of the wick structure 39 receiving the contacting members 360 of the top plate 36 therein. Thus the wick structure 39 covers the contacting members 360 entirely, including the bases 361 and the flanges 362, and covers a portion of the top plate 36 around the contacting members 360. A passage 60 is defined between each lateral side of the wick structure 39 and the side plate 34 of the tube 37 of the heat pipe 30.
When assembled, the top side of the condensation section 33 of the heat pipe 30 attaches to the bottom side of the fin unit 20 directly. The electronic components 90 are attached to the top plate 36 of the evaporation section 31 of the heat pipe 30 at the contacting members 360. Each electronic component 90 enters into a corresponding concave 363, with an outer surface 92 thereof attaching to a corresponding base 361 closely. Therefore, the electronic components 90 are partly received in the concaves 363 of the heat pipe 30. Other part of the heat pipe 30 without the contacting members 360 extend toward the circuit board 80 to be adjacent to the circuit board 80. Therefore, spaces around the electronic components 90 are utilized to accommodate the heat pipe 30, and a size, particularly a thickness, of the heat pipe 30 is increased, whilst a size of the electronic device which incorporates the thermal module does not need change.
During operation, the working fluid in the wick structure 39 of the heat pipe 30 absorbs the heat generated by the electronic components 90 and evaporates. Then the vapor moves to the condensation section 33 along the passages 60 at the lateral sides of the wick structure 39 to release the heat thereof to the fin unit 20. The vapor cools and condenses at the condensation section 33. The condensed working fluid returns to the evaporation section 31 by the capillary force of the wick structure 39, and evaporates into vapor again thereat. Since the heat pipe 30 of the thermal module has an enlarged size, a heat transfer capability of the heat pipe 30 is enhanced, whereby the heat of the electronic components 90 can be continuously and timely transferred to the fin unit 20 by the heat pipe 30. Finally the airflow of the blower 10 flowing across the fin unit 20 can take away the heat to an outside. Therefore, the thermal module can cool plural electronic components 90 simultaneously. A utilization efficiency of the thermal module is accordingly enhanced.
FIG. 4 shows a thermal module with an alternative heat pipe 50. The difference between this heat pipe 50 and the previous heat pipe 30 is the wick structure 59. In this embodiment, the wick structure 59 has a width substantially equaling to that of the chamber 55 of the heat pipe 50, and abuts the side plate 54 of the tube 57 at lateral sides thereof. The wick structure 59 is substantially U-shaped, includes a main body 590 and a pair of protrusions 592 extending upwardly from lateral sides of the main body 590, respectively. The main body 590 has a thickness equaling to a depth of the chamber 55 of the heat pipe 50 at the contacting members 560. A bottom side of the main body 590 abuts the bottom plate 52 of the heat pipe 50, and a top side of the main body 590 of the wick structure 59 abuts the bases 561 of the contacting members 560. Other portion of the top plate 56 around the contacting members 560 is spaced from the main body 590. The protrusions 592 extend from the top side of the main body 590 to abut lateral sides of the top plate 56 adjacent to the side plate 54 of the tube 57 of the heat pipe 20. A passage 70 is defined between the pair of protrusions 592 over the main body 590 for movement of the vapor. The contacting members 560 are located in the passage 70.
It is to be understood, however, that even though numerous characteristics and advantages of the disclosure have been set forth in the foregoing description, together with details of the structure and function of the disclosure, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.

Claims

1. A thermal module, comprising:

a blower comprising a housing and an impeller received in the housing, the housing defining an air inlet and an air outlet perpendicular to the air inlet;

a fin unit arranged at the air outlet of the blower; and

a heat pipe comprising a tube defining a chamber therein, and a wick structure disposed in the chamber of the tube, the heat pipe forming an evaporation section and a condensation section at opposite ends of the tube, respectively, the condensation section attaching to the fin unit, at least one contacting member depressed inwardly from the evaporation section of the heat pipe for accommodating an electronic component therein, a depth of the chamber at the at least one contacting member being less than that at other portion of the evaporation section of the heat pipe without the at least one contacting member.

2. The thermal module of claim 1, wherein the at least one contacting member comprises a base depressed in the tube and a flange extending upwardly from a periphery of the base, and the base has one of rectangular shape and square shape and adapted for contacting the electronic component.

3. The thermal module of claim 2, wherein the tube comprises a first plate, a second plate parallel to the first plate, and a side plate interconnecting the first plate and the second plate, the at least one contacting member being formed on the first plate, the wick structure comprising a main body and a pair of protrusions, the main body contacting the second plate and the first plate at the at least one contacting member, the protrusions extending from the main body to abut the first plate at a position spaced from the at least one contacting member.

4. The thermal module of claim 3, wherein a width between the protrusions is larger than a width of the base, the protrusions being spaced from the flange of the at least one contacting member, a channel being formed between the pair of protrusions.

5. The thermal module of claim 4, wherein a width of the main body of the wick structure substantially equals to that of the chamber of the tube, the protrusions extends from lateral sides of the main body and attaching to the side plate of the tube.

6. The thermal module of claim 2, wherein the tube comprises a first plate, a second plate parallel to the first plate, and a side plate interconnecting the first plate and the second plate, the at least one contacting member being formed on the first plate, the wick structure contacting the second plate and the first plate at the at least one contacting member, the wick structure covering the base and the flange of the at least one contacting member.

7. The thermal module of claim 6, wherein a width of the wick structure is smaller than that of the chamber, a passage is defined between the wick structure and the side plate of the tube.

8. The thermal module of claim 1, wherein the heat pipe is substantially Z-shaped, the condensation section of the heat pipe being linear-shaped, the evaporation section of the heat pipe being L-shaped.

9. The thermal module of claim 1, wherein a plurality of contacting members are formed on the evaporation section of the heat pipe.

10. A heat pipe, comprising:

a tube defining a chamber therein; and

a wick structure disposed in the chamber of the tube;

wherein the heat pipe respectively forms an evaporation section and a condensation section at opposite ends of the tube, at least one contacting member depressed inwardly from the evaporation section of the heat pipe for accommodating an electronic component therein, a depth of the chamber at the at least one contacting member being less than that at other portion of the evaporation section of the heat pipe without the at least one contacting member.

11. The heat pipe of claim 10, wherein the at least one contacting member comprises a base in the tube and a flange extending outwardly from a periphery of the base to connect with an outside of the tube, and the base is one of square-shaped and rectangle-shaped.

12. The heat pipe of claim 11, wherein the tube comprises a first plate, a second plate parallel to the first plate, and a side plate interconnecting the first plate and the second plate, the at least one contacting member being formed on the first plate, the wick structure comprising a main body and a pair of protrusions, the main body contacting the second plate and the first plate at the at least one contacting member, the protrusions extending from the main body to abut the first plate at a position spaced from the at least one contacting member.

13. The heat pipe of claim 12, wherein a width between the protrusions is larger than a width of the base, the protrusions being spaced from the flange of the at least one contacting member, a channel being formed between the pair of protrusions.

14. The heat pipe of claim 13, wherein a width of the main body of the wick structure substantially equals to that of the chamber of the tube, the protrusions extends from lateral sides of the main body and attaching to the side plate of the tube.

15. The heat pipe of claim 11, wherein the tube comprises a first plate, a second plate parallel to the first plate, and a side plate interconnecting the first plate and the second plate, the at least one contacting member being formed on the first plate, the wick structure contacting the second plate and the first plate at the at least one contacting member, the wick structure covering the base and the flange of the at least one contacting member.

16. The thermal module of claim 15, wherein a width of the wick structure is smaller than that of the chamber, a passage is defined between the wick structure and the side plate of the tube.

17. The heat pipe of claim 10, wherein the heat pipe is substantially Z-shaped, the condensation section of the heat pipe being linear-shaped, the evaporation section of the heat pipe being L-shaped, a plurality of contacting members being formed on the evaporation section of the heat pipe.