US20080277107A1

US20080277107A1 - Heat dissipating base structure

Info

Publication number: US20080277107A1
Application number: US11/800,916
Authority: US
Inventors: Pai-Yi Huang
Original assignee: Inventec Corp
Current assignee: Inventec Corp
Priority date: 2007-05-07
Filing date: 2007-05-07
Publication date: 2008-11-13

Abstract

A heat dissipating base structure includes a base; a plurality of heat dissipating fins disposed on the base and arranged in parallel to each other, each of the heat dissipating fins being formed with at least a first through hole and a second through hole corresponding to the first through hole; and at least a U-shaped heat pipe having a bending portion and two pipe leg portions extending from two ends of the bending portion respectively. The cross section of the pipe leg portions is smaller than the size of the first and second through holes. Each of the pipe leg portions is fixedly disposed in the first and second through holes at one side thereof respectively, and can move freely in the holes before being fixedly disposed.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates generally to heat dissipating base structures, and more particularly, to a heat dissipating base structure having a U-shaped heat pipe.
2. Description of Related Art
In a conventional heat dissipating base having a heat pipe, in order to solder the heat pipe to a plurality of heat dissipating fins of the heat dissipating base, a dispensing process comprising the following steps is performed: first, a groove or a hole is formed on an upper side of heat pipe holes of the heat dissipating fins, wherein the heat pipe is inserted into the heat dissipating fins through the heat pipe holes; then, a dispensing tip is inserted into the groove or the hole so as to dispense solder paste between the heat pipe and the heat dissipating fins, the solder paste at a melting state further flows through the spacing between the heat pipe and the heat dissipating fins by gravitational force and capillary force, thereby filling space between the heat pipe and the heat dissipating fins. However, the natural drain down of the solder paste cannot ensure the heat pipe and the heat dissipating fins are completely soldered together. If the heat pipe and the heat dissipating fins are not completely soldered together, the heat transfer effect from the heat pipe to the heat dissipating fins will be adversely affected, which further adversely affects the heat dissipating efficiency of the heat dissipating base.
Referring to FIGS. 1A and 1B, a conventional heat dissipating base having a heat pipe comprises a base 10; a plurality of heat dissipating fins 11 disposed on the base 10 and arranged in parallel to each other, each of the heat dissipating fins 11 having a plurality of heat pipe holes 110; and a U-shaped heat pipe 20 having two pipe legs inserted into the heat pipe holes 110 of the heat dissipating fins 11. On the upper side of the heat pipe holes 110 there are disposed openings 111 as shown in FIG. 1A or grooves 112 as shown in FIG. 1B such that a dispensing tip (not shown) can be inserted into inside of the heat dissipating fins 11 through the openings 111 or the grooves 112 for dispensing. As shown in FIG. 2A, after a dispensing process is performed to the structure of FIG. 1B, the solder paste 21 is attached to the U-shaped heat pipe 20. Subsequently, the whole heat dissipating base structure is put into an oven such that the solder paste 21 can be melted. The melted solder paste 21 further flows through and fills spacing between the heat pipe 20 and the heat pipe holes 110 of the heat dissipating fins 11 by gravitational force and capillary force, thereby soldering together the U-shaped heat pipe 20 and the heat dissipating fins 11.
However, the natural drain down of the solder paste 21 cannot ensure the heat pipe and the heat dissipating fins are completely soldered together. As shown in FIG. 2B, spacing between the lower portion of the U-shaped heat pipe 20 and the heat pipe hole 110 of the heat dissipating fins 11 is not filled with the solder paste 21, which can adversely affect the heat transfer effect from the heat pipe 20 to the heat dissipating fins 11 and the heat dissipating effect of the heat dissipating base. Further, since the diameter of the heat pipe holes 110 corresponds to the diameter of the U-shaped heat pipe 20, once the U-shaped heat pipe 20 is inserted into the heat pipe holes 110, the U-shaped heat pipe 20 cannot make any displacement. Therefore, it is not possible to perform a dispensing process to the lower pipe leg of the U-shaped heat pipe 20. Correspondingly, an opening or a groove similar to the above-mentioned opening or groove also needs to be formed for allowing a dispensing tip to enter into inside of the heat dissipating fins such that the lower pipe leg can be soldered to the heat dissipating fins. However, in the prior art, no such opening or groove is formed taking into account of such factors as heat dissipating area. Instead, the lower pipe leg of the U-shaped heat pipe 20 is kept separated from the heat dissipating fins 11, which thus leads to a poor heat conduction therebetween and accordingly reduces the heat dissipating effect of the heat dissipating base.
Therefore, how to overcome the above drawback has become urgent.

SUMMARY OF THE INVENTION

According to the above drawbacks, an objective of the present invention is to provide a heat dissipating base structure having elliptic through holes such that a heat pipe of the heat dissipating base structure can have a certain displacement freedom during a soldering process of the heat pipe, thereby facilitating the soldering process of the heat pipe and saving soldering time.
Another objective of the present invention is to provide a heat dissipating base structure with heat pipe having good soldering effect.
A further objective of the present invention is to provide a heat dissipating base structure having improved heat dissipating efficiency.
In order to attain the above and other objectives, the present invention discloses a heat dissipating base structure, comprising: a base; a plurality of heat dissipating fins arranged in parallel and disposed on the base, each of the fins having at least a first through hole and a second through hole corresponding to the first through hole; and at least a U-shaped heat pipe having a bending portion and two pipe leg portions extending from two ends of the bending portion, wherein, the cross section of the pipe leg portions is smaller than the size of the first and second through holes, the pipe leg portions are inserted into the first and second through holes and fixedly disposed to one side of the first and second through holes respectively, before being fixedly disposed, the pipe leg portions can freely move in the first and second through holes.
Preferably, the first and second through holes are elliptic. The first and second through holes can be arranged in a line perpendicular to a horizontal line. Alternatively, the first and the second through holes are arranged in a horizontal line. The U-shaped heat pipe is fixed to one side of the first and second through holes by a conductive material through a soldering method. The conductive material is one of gold, silver, solder paste, and a mixture of at least two thereof.
Compared with the prior art that solders the heat pipe and the heat dissipating fins together by forming little through holes for inserting of a dispensing tip so as to dispense the solder material and make the soldering material fill the spacing between the heat pipe and the heat dissipating fins through the gravitational force of the solder material and capillary force formed in the spacing between the heat pipe and the heat dissipating fins, the present invention provides elliptic through holes for a heat dissipating base structure such that heat pipe of the heat dissipating base structure can have a certain displacement freedom in the through holes. Thus, the position of the heat pipe can be adjusted for a dispensing process. Then through an external force, the heat pipe can be pressed to closely contact and fixedly soldered to one side of the through holes so as to obtain a good soldering effect between the heat pipe and the heat dissipating fins. Thereby, the heat conducting effect between the heat pipe and the heat dissipating fins is improved and further the heat dissipating efficiency of the whole heat dissipating base structure is improved.
Therefore, the heat dissipating base structure of the present invention overcomes the drawbacks of the prior art, obtains a good soldering effect, saves the time required for the soldering process and improves the heat dissipating efficiency.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A is a diagram of a conventional heat dissipating base structure having holes formed for insertion of a dispensing tip;

FIG. 1B is a diagram of a conventional heat dissipating base structure having grooves formed for inserting of a dispensing tip;

FIG. 2A is a partially expanded diagram showing a state after solder paste is dispensed to the structure of FIG. 1B;

FIG. 2B is a partially expanded diagram showing a soldering state between the heat pipe and the heat dissipating fins of the heat dissipating base structure of FIG. 2A;

FIG. 3 is a diagram of a heat dissipating base structure according to a first embodiment of the present invention;

FIG. 4A is a diagram showing a state of the heat dissipating base structure of FIG. 3 before heat pipe is soldered to the heat dissipating fins;

FIG. 4B is a diagram showing a state of the heat dissipating base structure of FIG. 3 after heat pipe is soldered to the heat dissipating fins;

FIG. 5 is a diagram of a heat dissipating base structure according to a second embodiment of the present invention;

FIG. 6A is a diagram showing a state of the heat dissipating base structure of FIG. 5 before heat pipe is soldered to the heat dissipating fins;

FIG. 6B is a diagram showing a state of the heat dissipating base structure of FIG. 5 after heat pipe is soldered to the heat dissipating fins;

FIG. 7 is a diagram of a heat dissipating base structure according to a third embodiment of the present invention;

FIG. 8A is a diagram showing a state of the heat dissipating base structure of FIG. 7 before heat pipe is soldered to the heat dissipating fins; and

FIG. 8B is a diagram showing a state of the heat dissipating base structure of FIG. 7 after heat pipe is soldered to the heat dissipating fins.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The following illustrative embodiments are provided to illustrate the disclosure of the present invention, these and other advantages and effects can be apparent to those skilled in the art after reading the disclosure of this specification. The present invention can also be performed or applied by other different embodiments. The details of the specification may be on the basis of different points and applications, and numerous modifications and variations can be made without departing from the spirit of the present invention.
FIG. 3 shows a heat dissipating base structure according to a first embodiment of the present invention. The heat dissipating base structure comprises a base 30 having a surface 31; a plurality of heat dissipating fins 40 disposed on the surface 31 of the base 30 and arranged in parallel to each other, each of the heat dissipating fins 40 having two elliptic first through holes 41 and two elliptic second through holes 42 corresponding to the first through holes 41 and disposed at an edge side of the heat dissipating fins 40 bonded with the base 30, the first and second through holes being arranged in a line perpendicular to a horizontal line; two U-shaped heat pipes 50 each having a bending portion 52 and two pipe leg portions 51 extending from two ends of the bending portion 52, the pipe leg portions 51 having a cross section smaller than sizes of the first through holes 41 and the second through holes 42. The pipe leg portions 51 are inserted into the first and second through holes 41, 42 respectively and fixed to an upper side of the first and second through holes 41, 42 by a conductive material such as solder paste 60. Alternatively, the conductive material can be one of gold, silver, solder paste or a mixture of at least two thereof.
Referring to FIGS. 4A and 4B, a solder paste 60 is dispensed to the two pipe leg portions 51 of the U-shaped heat pipes 50, respectively. As shown in FIG. 4A, the pipe leg portions 51 of the U-shaped heat pipes 50 are not in contact with the upper sides of the first and second through holes 41, 42, and the base 30 is separated from the heat dissipating fins 40. While the base 30 is soldered together with the heat dissipating fins 40, the U-shaped heat pipes 50 are pressed upward such that the pipe leg portions 51 of the heat pipes 50 can be closely in contact with the upper sides of the first and second through holes 41, 42, respectively. If the bending portions 52 of the U-shaped heat pipes 50 lack sufficient strength and are not capable of keeping the upper pipe leg portions 51 to be closely in contact with the upper sides of the first through holes 41, a tool such as an iron pipe can be inserted to the spacing between the upper pipe leg portions 51 and the lower portion of the first through holes 41 so as to press the upper pipe leg portions 51 upward and make the upper pipe leg portions 51 closely contact the upper side of the first through holes 41, thereby improving the soldering effect of the solder paste 60 on the pipe leg portions 51. As a result, the heat dissipating efficiency of the heat dissipating base structure can be improved.
FIG. 5 shows a heat dissipating base structure according to a second embodiment of the present invention. The heat dissipating base structure comprises a base 30 having a surface 31; a plurality of heat dissipating fins 40 stacked on the surface 31 of the base 30 and arranged in parallel to each other, each of the heat dissipating fins 40 having an elliptic first through hole 41 and an elliptic second through hole 42 corresponding to the first through hole 41, the first and second through holes being horizontally arranged, the first and second through holes 41, 42 having their major axes perpendicular to the horizontal line; and a U-shaped heat pipe 50 having a bending portion 52 and two pipe leg portions 51 extending from two ends of the bending portion 52, the bending portion 52 being soldered together with the base 30, the pipe leg portions 51 having a cross section smaller than the size of the first through hole 41 and the second through hole 42. The pipe leg portions 51 are inserted into the first through hole 41 and the second through hole 42 and fixed to an upper side of the first and second through holes 41, 42 by a conductive material such as solder paste 60. Alternatively, the conductive material can be one of gold, silver, solder paste or a mixture of at least two thereof.
Referring to FIGS. 6A and 6B, solder paste 60 is dispensed to the two pipe leg portions 51 of the U-shaped heat pipes 50, respectively. As shown in FIG. 6A, the pipe leg portions 51 of the U-shaped heat pipe 50 are not in contact with the upper sides of the first and second through holes 41, 42. Then, an iron pipe is inserted into the spacing between the pipe leg portions 51 and the lower portions of the first and second through holes 41, 42 so as to press the pipe leg portions 51 upward and make the pipe leg portions 51 closely contact the upper sides of the first and second through holes 41, 42, respectively, as shown in FIG. 6B, thereby improving the soldering effect of the solder paste 60 on the pipe leg portions 51. As a result, the heat conducting effect is improved, and further the heat dissipating efficiency of the heat dissipating base structure is improved.
FIG. 7 is a diagram showing a heat dissipating base structure according to a third embodiment of the present invention. The heat dissipating base structure comprises a base 30 having a surface 31; a plurality of heat dissipating fins 40 stacked on the surface 31 of the base 30 and arranged in parallel to each other, each of the heat dissipating fins 40 having an elliptic first through hole 41 and an elliptic second through hole 42 corresponding to the first through hole 41, the first and second through holes being horizontally arranged, the first and second through holes 41, 42 having their major axes arranged in a horizontal line; and a U-shaped heat pipe 50 having a bending portion 52 and two pipe leg portions 51 extending from two ends of the bending portion 52, the bending portion 52 being soldered together with the base 30, the pipe leg portions 51 having a cross section smaller than the size of the first through hole 41 and the second through hole 42. The pipe leg portions 51 are inserted into the first and second through holes 41, 42 respectively and fixed to one side of the first and second through holes 41, 42 by a conductive material such as solder paste 60. In the present embodiment, the pipe leg portions 51 are fixed to a left side of the first and second through holes 41, 42 respectively. Alternatively, the conductive material can be one of gold, silver, solder paste or a mixture of at least two thereof.
Referring to FIGS. 8A and 8B, solder paste 60 is dispensed to the two pipe leg portions 51 of the U-shaped heat pipes 50, respectively. As shown in FIG. 8A, the pipe leg portions 51 of the U-shaped heat pipe 50 are not in contact with the left sides of the first and second through holes 41, 42. Then, an iron pipe is inserted to the spacing between the pipe leg portions 51 and right sides of the first and second through holes 41, 42 so as to press the pipe leg portions 51 leftward and make the pipe leg portions 51 closely contact the left sides of the first and second through holes 41, 42, thereby improving the soldering effect of the solder paste 60 on the pipe leg portions 51. As a result, the heat conducting effect is improved, and further the heat dissipating efficiency of the heat dissipating base structure is improved.
Compared with the prior art, the present invention provides elliptic through holes for a heat dissipating base structure such that a heat pipe of the heat dissipating base structure can have a certain displacement freedom in the through holes. Thus, the position of the heat pipe can be adjusted for a dispensing process. Then through an external force, the heat pipe can be pressed to closely contact and fixedly soldered to one side of the through holes so as to obtain a good soldering effect between the heat pipe and the heat dissipating fins. Thereby, the heat conducting effect between the heat pipe and the heat dissipating fins is improved and further the heat dissipating efficiency of the whole heat dissipating base structure is improved.
Therefore, the heat dissipating base structure of the present invention overcomes the drawbacks of the prior art, obtains a good soldering effect, saves the time required for the soldering process and improves the heat dissipating efficiency.
The above-described descriptions of the detailed embodiments are only to illustrate the preferred implementation according to the present invention, and it is not to limit the scope of the present invention, Accordingly, all modifications and variations completed by those with ordinary skill in the art should fall within the scope of present invention defined by the appended claims.

Claims

1. A heat dissipating base structure, comprising:

a base;

a plurality of heat dissipating fins disposed on the base and arranged in parallel to each other, each of the heat dissipating fins having at least a first through hole and a second through hole corresponding to the first through hole; and

at least a U-shaped heat pipe having a bending portion and two pipe leg portions extending from two ends of the bending portion, the pipe leg portions having a cross section smaller than sizes of the first and second through holes and being inserted into the first and second through holes and fixedly disposed to one side of the first and second through holes respectively, the pipe leg portions, when not being fixedly disposed, capable of freely moving in the first and second through holes.

2. The heat dissipating base structure of claim 1, wherein the first through hole is elliptic.

3. The heat dissipating base structure of claim 1, wherein the second through hole is elliptic.

4. The heat dissipating base structure of claim 1, wherein the first and second through holes are arranged in a line perpendicular to a horizontal line.

5. The heat dissipating base structure of claim 1, wherein the first and the second through holes are arranged in a horizontal line.

6. The heat dissipating base structure of claim 1, wherein the U-shaped heat pipe is fixed to one side of the first and second through holes by a conductive material through a soldering method.

7. The heat dissipating base structure of claim 6, wherein the conductive material is one of gold, silver, solder paste, and a mixture of at least two thereof.