JP2001284511A - Cooling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling device which enables space saving. SOLUTION: A cooling device 1 is constituted of a heat-receiving base plate 3, a heat dissipation base plate 5 and heat pipes 9 which are extended so as to connect both base plates 3 and 5 with each other. The connecting parts 17 of the heat pipes 9 to connect both base plates 3 and 5 with each other are bundled in the vicinity of the center of the part between bath phase plates 3 and 5. By, bundling the heat pipes 9 in the vicinity of the center, saving in the space of the device 1 is enabled and even though an obstructive object, such as a substrate, exists between both base plates 3 and 5, this object is avoided and the pipes 9 can be arranged between both base plates 3 and 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cooling device for cooling a heating element such as a semiconductor element.

[0002]

2. Description of the Related Art A heat sink mainly composed of a base plate to which a heating element is attached and a heat pipe attached to the base plate is generally used for a cooling device for a heating element such as a semiconductor element mounted on an electronic device. ing. The heat pipe is one in which a working fluid such as water, butane, or alcohol is sealed after a closed space inside is evacuated. The portion of the heat pipe in contact with the base plate to which the heating element is attached serves as a heat receiving section, and heat is transmitted from the heating element. The heat transmitted to the heat receiving section evaporates the working fluid in the heat pipe of the heat receiving section, and the vapor moves to the heat radiating section of the heat pipe to radiate heat, and the vapor returns to a liquid. Due to the phase change and movement of the working fluid in the enclosed space, the heat of the heating element is diffused. In order to further increase the heat radiation efficiency, the heat radiation part is provided with heat radiation fins.

[0003]

Such a cooling device is generally disposed in a housing of an electronic device such as a computer. 2. Description of the Related Art As electronic devices become smaller and more sophisticated in recent years, it is necessary to arrange many electronic components and a board on which components are mounted in a housing. For this reason, the space for arranging the cooling device is narrow and often has a limited shape, and there is a case where a sufficient space for arranging the cooling device near a heat-generating element such as a semiconductor cannot be obtained. .

[0004] The present invention has been made in view of the above problems, and has as its object to provide a cooling device capable of saving space. In particular, it is an object of the present invention to provide a cooling device capable of disposing a heat radiating portion at an arbitrary position.

[0005]

In order to solve the above-mentioned problems, a cooling device according to the present invention comprises a heat-receiving base plate on which a heating element is mounted, a heat-dissipating base plate serving as a heat-dissipating portion, and a reciprocating device. A cooling device comprising: a meandering thin tube heat pipe provided; wherein the meandering thin tube heat pipe is bent and bundled. Alternatively, the meandering thin tube heat pipe is twisted.

[0006] Bending and bundling or twisting the meandering thin tube heat pipe connecting the heat receiving base plate and the heat radiating base plate saves space. Furthermore, even if an obstructive object such as a substrate exists between the two plates, the heat pipe can be disposed avoiding this object. Further, the heat receiving base plate and the heat radiating base plate can be arranged in various postures, and the space can be saved. Here, the heat receiving base plate and the heat radiating base plate are not limited to flat plates, but include a liquid cooling block.

According to another aspect of the present invention, there is provided a cooling device comprising: a heat receiving base plate on which a heating element is mounted; a heat radiating base plate serving as a heat radiating portion; A cooling device comprising:
The heat-receiving base plate and the heat-dissipating base plate are characterized in that an arbitrary patterned thin tube heat pipe embedding groove is formed. For the heat receiving base plate and the heat dissipation base plate,
By forming the pipe-embedding groove for arranging the thin tube heat pipe in an arbitrary pattern, the heat conduction between the base plate and the heat pipe can be improved, and the heat transport direction can be directed to a desired direction.

[0008] In this aspect, it is preferable that the pattern extends in the vertical and horizontal directions. Heat can be transported in the vertical and horizontal directions by the thin tube heat pipe, and the heat transport efficiency is improved.

Alternatively, the patterned groove may be linear, and the turn portion of the thin tube heat pipe may be located outside the heat receiving base plate and the heat radiating base plate. By making the patterned groove straight and providing the turn portion outside the heat receiving base plate and the heat radiating base plate, the processing of the pipe buried groove formed in each plate becomes easy. Therefore, an extruded material such as aluminum can be used, and the productivity is improved.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view showing the structure of the cooling device according to the first embodiment of the present invention. The cooling device 1 includes a heat receiving base plate 3, a heat radiating base plate 5, and a heat pipe 9 extending so as to connect the two base plates. A heat generating component such as a semiconductor element is attached to the heat receiving base plate 3. In this example, the heat-receiving base plate and the heat-dissipating base plate may be either left or right in the drawing.

The heat receiving base plate 3 and the heat radiating base plate 5 are made of aluminum or the like having high thermal conductivity, and have a width of 120 mm, a length of 100 mm, and a thickness of 10 mm as an example. A plurality of parallel grooves penetrating from the inner end face to the outer end face are formed in both base plates 3 and 5. This through groove becomes the buried groove 7 of the heat pipe. The buried groove 7 may be formed by extruding the base plate or may be formed by cutting. Two grooved plates are overlapped and joined with a heat pipe therebetween. Those formed by extrusion are easy to manufacture, and those formed by cutting are easy to form various patterns as described later.

The heat pipe 9 has strength and flexibility and is made of a material such as aluminum having high thermal conductivity. As an example of dimensions, the outer diameter is 1.6 mm, and the inner hole diameter is 1.2 mm. It is a long pipe. One end of the heat pipe 9 is opened to form an inlet 11 for a working fluid such as butane, and the end 13 is closed. The heat pipe 9 has a predetermined distance (for example, 300
mm) so as to reciprocate between the heat-receiving base plate 3 and the heat-dissipating base plate 5 which are disposed apart from each other, and are embedded in the embedding grooves 7 of both base plates 3 and 5. Connected thermally. In this example, the working fluid filling port 11 and the end 13 of the heat pipe 9 and the turn portion 15 (turnback portion) of the meandering heat pipe 9 are provided.
Are located outside the outer end faces of the base plates 3 and 5. That is, the heat pipe 9 is folded back when it comes out of the embedding groove 7 on the outer end surfaces of the base plates 3 and 5, and is embedded in the next embedding groove 7. Thermally conductive grease is applied to the embedding grooves 7 of both base plates 3 and 5,
The heat pipe 9 and both base plates 3 and 5 are thermally connected.

A connecting portion 17 of the heat pipe 9 for connecting the base plates 3 and 5 is bundled near the center of the base plates 3 and 5. This configuration will be described with reference to FIG. FIG.
FIG. 2 is a perspective view showing a state of the heat pipe before the cooling device of FIG. 1 is formed. The heat pipe connecting portion 17 protruding from the opposed inner end surfaces 3a, 5a of the base plates 3, 5 is the longest on the side surfaces 3b, 5b of the base plates 3, 5, and becomes shorter toward the center, It is the shortest in the center. The length of the central heat pipe connecting portion 17a is a substantial distance between the two base plates 3, 5. In this state, one outer heat pipe connecting portion 17b at the central portion is bent along the central heat pipe connecting portion 17a, and further one outer heat pipe connecting portion is connected to the inner heat pipe connecting portion 17b. Bend continuously along the way. The heat pipe connection portion 17 is bent in this manner and bundled near the center. At this time, it may be bundled with a cord or a wire.

A space is saved by bending and bundling a heat pipe connecting the heat receiving base plate 3 and the heat radiating base plate 5. Further, since the bundled heat pipe connecting portions 17 have a certain degree of flexibility, the heat receiving base plate 3 and the heat radiating base plate 5 can be arranged in various postures.

The heat pipe formed so as to meander on the heat receiving base plate and the heat radiating base plate as described above has the following characteristics (see Japanese Patent Application Laid-Open No. 4-190090). (1) Both ends of the thin tube are connected to each other in a freely circulating manner and are sealed. (2) A part of the thin tube is a heat receiving part, and the other part is a heat radiating part. (3) The heat receiving portion and the heat radiating portion are alternately arranged, and the thin tube meanders between both portions. (4) A two-phase condensable fluid is sealed in the thin tube. (5) The inner wall of the thin tube has a diameter equal to or less than the maximum diameter at which the working fluid can circulate or move while always closing the hole.

FIGS. 3 to 5 are perspective views schematically showing one example of an arrangement state of the cooling device of FIG. In the cooling devices of these examples, the radiation fins 19 are formed on the radiation base plate 5. The heat receiving component 21 is attached to the heat receiving base plate 3. An obstacle 23 such as a board or an electronic component is arranged around the heat-generating component 21 on the heat-receiving base plate 3, and there is no space in which the heat-radiating base plate 5 is installed.

In the arrangement shown in FIG. 3, the heat radiating base plate 5 is arranged in the same direction as the heat receiving base plate 3.
The heat pipe connecting portion 17 is bent in the surface direction of the base plates 3 and 5 and bundled near the center so as to avoid an obstacle between the base plates 3 and 5. Such an arrangement state is applied when there is an obstacle such as an electronic device between the heat receiving unit and the heat radiating unit in the narrow housing.

In the arrangement shown in FIG. 4, the heat radiation base plate 5 is arranged in a direction different from the heat receiving base plate 3 (a direction orthogonal to the heat receiving base plate 3). The heat pipe connecting portion 17 is bent in the surface direction of the heat receiving base plate 3 so as to avoid an obstacle between the two base plates 3 and 5, and further twisted in a direction perpendicular to the base plate 3 and bundled near the center. I have. Such an arrangement state is applied in FIG. 3 when the installation space of the heat radiator is limited or when there is an obstacle when the heat radiator is horizontally installed.

The arrangement shown in FIG. 5 is such that the heat receiving base plate 3 is arranged in a direction different from (or orthogonal to) the heat radiating base plate 5 and further above the base plate 5. The heat pipe connecting portion 17 is bent in the surface direction of the heat receiving base plate 3 so as to avoid an obstacle between the two base plates 3 and 5, is further raised while being twisted upward, and is bundled near the center. ing. Such an arrangement state is applied when there is a restriction on the installation direction of the blower fan in FIG.

When manufacturing the cooling device arranged in the above state, the length of each position of the heat pipe connecting portion 17 in each installation state is determined in advance, and as shown in FIG. It is necessary to manufacture a cooling device in a proper state.

FIG. 6 is a plan view showing the structure of a cooling device according to an embodiment of the second aspect of the present invention. In the cooling device 31 of this example, the turn portion 45 of the heat pipe 39 does not protrude outside the two base plates 33 and 35, and the two base plates 3
3, 35 are formed. In addition, heat pipe 39
The working fluid filling port and the end are also located in one of the base plates (radiation base plate 35 in this example), and are formed as turn portions 46 that are connected at both ends. By arranging the heat pipe 39 in such a pattern, the pattern is in a loop shape (closed loop shape), so that the working fluid circulates smoothly, and as a result, the heat transport function is stabilized and improved. There is.

FIG. 7 is a plan view showing the structure of a cooling device according to another embodiment of the present invention. Cooling device 51 of this example
In the first embodiment, a plurality of loop-shaped heat pipes 59 having different lengths are embedded in both base plates. The longest loop-shaped heat pipe 59a turns from one outside of the heat dissipation base plate 55 along the outer periphery of the heat reception base plate 53 and returns to the other outside of the heat dissipation base plate 55. The second longest loop heat pipe 59b is arranged along the inside of the outermost loop heat pipe 59a. As described above, the loop-shaped heat pipes 59 are arranged from the outside to the inside in the order of length. At this time, the heat pipes of the heat receiving base plate 53 are located along the three side surfaces of the base plate 53, and a portion extending in the vertical direction and a portion extending in the horizontal direction are formed in the drawing. All the turn portions of each loop-shaped heat pipe 59 are located in both base plates 53 and 55.
By arranging the heat pipes in this manner, in the heat receiving base plate 53, the heat is transported in two directions, that is, in the vertical and horizontal directions along the direction of the heat pipes, so that the heat can be transported two-dimensionally.

FIG. 8 is a plan view showing the structure of a cooling device according to a third embodiment of the present invention. Cooling device 71 of this example
In the cooling device of FIG. 1, the working fluid filling port and the end of the heat pipe 79 are connected outside the heat receiving base plate 75 to form a turn portion 86. By arranging the heat pipe in such an arrangement, the groove for embedding the heat pipe can be formed straight. Therefore, cutting and extrusion can be easily performed. Further, since the heat receiving portion base plate and the heat radiating portion base plate have the same shape, productivity is improved.

In the second to fourth embodiments, the heat receiving base plate and the heat radiating base plate may be interchanged.

[0025]

As is clear from the above description, according to the present invention, meandering thin tube heat pipes arranged to reciprocate between the heat receiving base plate and the heat radiating base plate are bent and bundled, or , So that it is twisted, saving space. Further, even if a disturbing object such as a substrate exists between the two plates, the cooling device can be arranged avoiding the object.

[Brief description of the drawings]

FIG. 1 is a plan view showing a structure of a cooling device according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a state of a heat pipe before the cooling device of FIG. 1 is formed.

FIG. 3 is a perspective view schematically showing an example of an arrangement state of the cooling device of FIG. 1;

FIG. 4 is a perspective view schematically showing an example of an arrangement state of the cooling device of FIG. 1;

FIG. 5 is a perspective view schematically showing an example of an arrangement state of the cooling device of FIG. 1;

FIG. 6 is a plan view showing the structure of a cooling device according to an example of the second aspect of the present invention.

FIG. 7 is a plan view illustrating a structure of a cooling device according to another embodiment of the present invention.

FIG. 8 is a plan view illustrating a structure of a cooling device according to a third embodiment of the present invention.

[Explanation of symbols]

1, 31, 51, 71 Cooling device 3, 33, 53, 73 Heat-receiving base plate 5, 35, 55, 75 Heat-dissipating base plate 7 Embedded groove 9, 39, 59, 79 Heat pipe 11 Working fluid filling port 13 Terminal 15, 45, 85 turn portion 17 heat pipe connection portion 19 heat radiation fin 21 heat generating component 23 obstacle 46, 59, 86 turn portion

Claims (5)

[Claims] 1. A cooling device comprising: a heat receiving base plate to which a heating element is attached; a heat radiating base plate serving as a heat radiating portion; and a meandering thin tube heat pipe arranged to reciprocate between the two plates; A cooling device, wherein the meandering thin tube heat pipe is bent and bundled. 2. A cooling device comprising: a heat receiving base plate to which a heating element is attached; a heat radiating base plate serving as a heat radiating portion; and a meandering thin tube heat pipe disposed so as to reciprocate between the two plates; A cooling device, wherein the meandering thin tube heat pipe is twisted. 3. A cooling device comprising: a heat receiving base plate to which a heating element is attached; a heat radiating base plate serving as a heat radiating portion; and a meandering thin tube heat pipe arranged to reciprocate between the two plates; A cooling device, wherein an arbitrary patterned thin tube heat pipe embedding groove is formed in the heat receiving base plate and the heat radiating base plate. 4. The cooling device according to claim 3, wherein said pattern extends vertically and horizontally. 5. The method according to claim 3, wherein the patterned groove is linear, and a turn portion of the thin tube heat pipe is located outside the heat receiving base plate and the heat radiating base plate. Cooling system.