JP3334308B2 - Heat pipe and heat pipe radiator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pipe suitable for use in a heat pipe radiator for cooling heat-generating components in electronic equipment, and a heat pipe radiator for electronic equipment. .

[0002]

2. Description of the Related Art A conventional heat pipe type radiator that cools heat-generating components in an electronic device, which is considered to be the most preferable, will be described with reference to FIGS. 7 and 8. FIG.
FIG. 7 is a partial side view showing a state where the heat pipe radiator is attached to a substrate in an electronic device. FIG. 8 is a front view of the heat pipe radiator shown in FIG.

[0003] Four heat pipes 1 ', each of which is flattened over its entire length, are arranged so that their flat surfaces are located vertically, and a heat receiving plate 2' is provided on a heat receiving portion (evaporating portion) 10 '. A heat diffusion plate 3 'is attached to the heat radiating portion (condensing portion) 11'. Heat pipe 1 '
Is flattened by pressurizing a cylindrical heat pipe after enclosing the working fluid. The heat dissipating fins 4 'are fixed to the heat diffusion plate 3' along the width direction thereof by brazing or the like. The radiating fins 4 'have a honeycomb structure, and the honeycomb-shaped holes 40' extend along the width direction of the heat diffusion plate 3 '(that is, along the width direction of the heat radiating portion 11' of the heat pipe). Has become
The number of holes 40 ′ is 48 on each of the upper and lower sides of the heat diffusion plate 3 ′, for a total of 96 holes.
Individual.

The heat receiving portion 10 'of the heat pipe 1 is embedded in the heat receiving plate 2' and the heat radiating portion 11 'is embedded in the heat diffusing plate 3'. Specifically, the heat receiving plate 2 ′ and the heat diffusion plate 3 ′ are upper and lower split molds 2 a, 2 b and 3, respectively.
a, 3b and split molds 2a, 2b and 3
The heat receiving portion 10 ′ and the heat radiating portion 1
1 'is soldered respectively. 21 is a leg of the heat receiving plate 2 '.

[0005] As shown in FIGS. 7 and 8, the heat pipe type radiator has a heat generating electronic device such as a semiconductor element mounted on the substrate 5 via the high heat conductive rubber 60 on the lower surface of the heat receiving plate 2 ′. The parts 6 are bonded (bonded with a heat conductive adhesive),
The heat radiation fins 4 'are arranged along the holes 40' of the honeycomb structure, that is, in the direction of the arrow a in FIG. 8 (or the reverse direction).
The electronic component 6 is cooled while sending air from the air.
That is, the heat of the electronic component 6 is transmitted to the heat radiating unit 10 ′ via the heat receiving plate 2 ′ to evaporate the internal working fluid, transported together with the steam to the heat radiating unit 11 ′, and radiated through the heat diffusion plate 3 ′. Released into the air by the fins 4 '. At the same time, the vapor condenses. The heat from the electronic component 6 is radiated by the continuous repetition of such heat exchange.

[0006]

A radiator of this type using a flat heat pipe radiates wind along both flat surfaces of the radiator 11 'in order to exchange heat more effectively. Need to shed. In other words, the heat radiating heat fins 4 ′ extend in the width direction of the heat diffusion plate 3 ′ in the heat radiating portion 11 ′ (the heat radiating portion 1 ′).
1 'width direction). However, the flat heat pipe 1 'in the conventional heat pipe radiator has a flat surface (width surface) of the heat receiving portion 10'.
And the eccentric plane of the heat radiating section 11 'are formed in the same direction, and the radiating section 11' of each heat pipe 1 'must be installed with the eccentric plane directed up and down. Therefore, since the heat diffusion plate 3 'and the radiating fin 4' in the heat radiating portion 11 'of each heat pipe 1' must be made common and the entire length thereof needs to be long, the radiating fin efficiency is poor, and the heat resistance and ventilation resistance are low. Becomes larger.

When the air is blown, the same air successively passes on both sides of the heat radiating portion 10 'of each heat pipe. Therefore, the temperature of the air (wind) rises while passing between the heat radiating fins 4', and the air rises. As the temperature approaches the end of the radiating fin 4 '(left end in FIG. 8), the difference between the temperature and the surface temperature of the radiating fin 4' disappears, and the heat radiation performance decreases. At the same time, the temperature of the heat pipe located on the downstream side of the air flow becomes higher than the temperature of the heat pipe located on the upstream side, and the electronic components 6 vary in temperature due to differences in their installation positions. Furthermore, depending on the installation space of the blower fan,
In some cases, it is desired to install a blower fan so as to send air to the radiating fins 4 'in the vertical direction in FIG. 7, but such a fan cannot be provided with a conventional heat pipe radiator.

In the above-described conventional heat pipe radiator, the heat receiving portion 10 'and the heat radiating portion 11' are soldered to the split concave surfaces of the heat receiving plate 2 'and the heat diffusion plate 3', respectively. , Where most of the heat transfer is performed, between the uneven plane of the heat receiving portion 10 ′ and the heat receiving plate 2 ′, and the heat radiating portion 11 ′.
A gap (void) is generated between the eccentric plane and the heat diffusion plate 3 ′, and the thermal conductivity is reduced. Further, the specific gravity of the solder is large and the overall weight is large.

SUMMARY OF THE INVENTION It is an object of the present invention to improve the above-mentioned problems, that is, a radiator for a radiator which has a high efficiency of a radiating fin, a low ventilation resistance, and can blow air vertically to the radiating fin. An object of the present invention is to provide a heat pipe and a heat pipe type radiator.

[0010]

In order to achieve the above-mentioned object, a heat pipe according to the present invention has a heat receiving portion and a heat radiating portion each having a flat length and a predetermined length. and the polarization plane of the radiating portion, each longitudinal
One is almost horizontal over its entire length in end view
When the other is formed to be almost vertical over the entire length
Things .

[0011] The heat pipe radiator according to the present invention comprises:
A heat pipe formed as described above, a heat receiving plate attached to a heat receiving portion of the heat pipe, and a heat diffusion plate attached to a heat radiating portion of the heat pipe, wherein the heat receiving portion of the heat receiving portion The eccentric plane is embedded in the heat receiving plate so as to be substantially parallel to both sides in the width direction of the heat receiving plate, and the heat radiating portion is in a state where the uneven plane of the heat radiating portion is substantially parallel to both surfaces in the width direction of the heat diffusing plate. The heat dissipating fin is fixed along the width direction of the heat diffusing plate. The heat receiving portion is inserted into an insertion hole formed in the heat receiving plate, and the heat radiating portion is inserted into an insertion hole formed in the heat diffusion plate, respectively. It is preferable that each of the insertion holes is in close contact with the inner wall. It is preferable that the radiation fin has a honeycomb structure in which holes extend along a width direction of the heat diffusion plate.

[0012]

The heat pipe according to the present invention has a flat shape.
Having a heat receiving portion and a heat radiating portion of a predetermined length processed into
The plane of the heat receiving section and the plane of the heat radiating section are
One end is almost horizontal over the entire length
Sometimes the other is almost vertical over its entire length
When a plurality of heat pipes are arranged so that the uneven planes of their heat receiving sections face up and down, and a common heat receiving plate is attached to each heat receiving section, the heat radiating section of each heat pipe has Each heat dissipating portion is provided with a separate heat diffusion plate.

Therefore, the radiator using the heat pipe according to the present invention is fixed to each heat diffusion plate and the heat diffusion plate when the air is blown along the width direction of the heat diffusion plate in the heat radiation portion of each heat pipe. Different air comes into contact with the radiation fins. Therefore, the fin efficiency is relatively improved, the heat resistance and the ventilation resistance are smaller, and the heat dissipation performance is further improved.

Even if a plurality of electronic components are mounted on the heat receiving surface of the heat receiving plate, the heat receiving portion of each heat pipe in the radiator is orthogonal to the heat receiving surface on which the electronic components are mounted. Can be blown so that different air hits each other, so that the temperature of each heat pipe of the radiator becomes almost equal, and therefore, it is possible to eliminate the temperature variation due to the difference in the mounting position between the electronic components. it can.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a heat pipe, a heat pipe type radiator and a method of manufacturing the same according to the present invention will be described below with reference to FIGS. FIG. 1 is a front view showing one embodiment of a heat pipe type radiator according to the present invention.
3 is a side view of the heat pipe type radiator of FIG. 1, FIG. 3 is a partially omitted perspective view of a heat pipe used in the radiator of FIG. 1, and FIG. 4 shows a heat receiving portion or a heat radiating portion of the heat pipe of FIG. FIG. 5 is a partial end view showing a state where the heat receiving plate or the heat diffusion plate is inserted into the insertion hole, FIG. 5 is a partial end view showing a state where the heat receiving portion or the heat radiating portion is expanded from the state shown in FIG. 4, and FIG. 7 is a partially omitted perspective view showing another embodiment, FIG. 7 is a partial side view showing a state in which a conventional heat pipe radiator is attached to a substrate in an electronic device, and FIG. 8 is a front view of the heat pipe radiator in FIG. FIG. 9 and FIG. 9 are line graphs comparing the heat radiation performance of the heat pipe type radiator according to the embodiment of the present invention and the conventional radiator.

The heat pipe radiator shown in FIGS. 1 and 2
Four heat pipes 1 arranged in a horizontal direction, and a common heat receiving plate 2 attached to a heat receiving portion 10 of each heat pipe 1
And heat diffusion plates 3 separately attached to the heat radiating portions 11 of the heat pipes 1 and radiation fins 4 attached to each heat diffusion plate 3.

Each heat pipe 1 has an outer diameter of 16 mm and a thickness of 1
mm, a copper cylindrical heat pipe with an inner groove (not shown) is pressurized and flattened as shown in FIGS. 1 to 3. As shown in FIG. It is composed of a heat receiving portion 10 and a heat radiating portion 11 having a diameter (width) w1 = less than 23 mm and a short outer diameter (height) h1 = 4 mm.
= 210 mm. The working fluid of the heat pipe 1 is pure water. One of the uneven plane of the heat receiving section 10 and the uneven plane of the heat radiating section 11 are all in the end view in the longitudinal direction.
When the other is almost horizontal over the length, the other is almost
The direction is almost 90 degrees different from the vertical state .

The heat receiving portion 10 of each heat pipe 1 has a width w2
= 100 mm, length L2 = 70 mm, thickness t2 = 6 mm embedded in a heat receiving plate 2 made of an aluminum alloy, and each radiator 11 has a width w3 = 46 mm, a length L3 = 60.5 mm, and a thickness t3. = 6 mm embedded in a heat diffusion plate 3 made of an aluminum alloy. Therefore, the uneven plane of the heat receiving unit 10 and the width surface of the heat receiving plate 2, and the uneven plane of the heat radiation unit 11 and the width surface of the heat diffusion plate 3 are parallel to each other.

In this embodiment, the heat receiving unit 10 and the heat receiving plate 2
The heat radiating portion 11 and the heat diffusion plate 3 are fixed to each other by the following method. When processing a cylindrical heat pipe (not shown) into a flat heat pipe 1, as shown in FIG. 4, the heat receiving portion 10 and the heat radiating portion 11 have a longer outer diameter of 23 mm and a shorter outer diameter h1 of about 3.5 mm. Process so that it becomes. On the other hand, the heat receiving plate 2 and the heat diffusion plate 3 have a width w2 along the length direction.
Insert holes 20 and 30 each having 0 = 24 mm and a height h20 = 4 mm are formed. Then, the heat receiving portion 10 is inserted into the insertion hole 20 of the heat receiving plate 2 and the heat radiating portion 11 is inserted into the insertion hole 30 of the heat diffusion plate 3, and these are kept at 170 ° C. to 200 ° C. while keeping them horizontal. It is placed in a thermostat (not shown) and heated. The above-mentioned heating causes the working fluid in the heat pipe 1 to evaporate and increase the internal pressure.
And the heat radiating portion 11 is directed in a circular direction, that is, a short outer diameter h.
1 expands in the direction of enlargement (vertical direction in FIG. 4). Due to this expansion, as shown in FIG. 5, the uneven planes of the heat receiving portion 10 and the heat radiating portion 11 come into close contact with the inner wall surfaces of the insertion holes 20 and 30 in the width direction, and stop the expansion. When the uneven planes of the heat receiving portion 10 and the heat radiating portion 11 are in close contact with the inner wall surfaces of the insertion holes 20 and 30 in the width direction, these are taken out of the thermostat.

Each of the radiation fins 4 of this embodiment has a honeycomb structure made of an aluminum alloy, and has a honeycomb-shaped hole 40.
Are fixed to each heat diffusion plate 3 by a heat conductive adhesive so as to extend along the width direction of each heat diffusion plate 3. The size of the honeycomb-shaped hole 40 is 4 mm long × 4.5 mm wide, and the hole 40
The thickness t4 of the partition wall between them is 0.5 mm. Hole 4
The number of zeros is 24 for each side of each heat diffusion plate 3, that is, 196 in total. The total size of the heat diffusion plate 3 and the radiation fins 4 is L4 = 60.4 mm, W4 = 104 mm, and H4 = 46 mm.

As shown in FIG. 2, the heat pipe radiator of this embodiment is used by bonding the back surface of the heat receiving plate 2 to the heat-generating electronic component 6 on the substrate 5 via the high thermal conductive rubber 60.
The heat of the electronic component 6 is transmitted to the heat receiving portion 10 of the heat pipe 1 via the heat receiving plate 2, is conveyed to the heat radiating portion 11 by evaporation of the working fluid in the heat receiving portion 10, and is radiated through the heat diffusing plate 3. 4 to be released into the air. The vapor condenses and returns to the heat receiving unit 10.

The sample A which is the heat pipe radiator of the above embodiment is the same as the sample A in the size and material of each part (however, the number of holes 40 'of the heat radiation fin is 96).
And a sample B, which is a conventional heat pipe radiator shown in FIGS. 7 and 8, was manufactured, and a heat radiation performance test was performed on both samples A and B in the following manner. The result was as shown in FIG. (1). The electronic component 6 in FIGS. 2 and 7 was replaced with a heater (not shown). (2). Fans having the same capacity are respectively provided for the radiating fins 4 of the sample A from the direction of the arrow b in FIG. 2 and for the radiating fins 4 'of the sample B from the direction of the arrow a of FIG. Blasted. (3). The heating value of the heater was changed and the temperature rise near the heater was examined.

For example, when the electronic component 6 is a semiconductor element (IGBT) having a heating value of 100 W, the limit temperature (case temperature of the semiconductor element) is 40 ° C. Applying this to the results of FIG. 8, the maximum possible super load of the radiator sample A according to the embodiment of the present invention is about 105 W, whereas the maximum radiator of the conventional radiator sample B is about 105 W. Since the super load is about 60W, sample A is sample B
This means that the heat radiation performance is improved by about 75%.

The heat pipe radiator of the above-described embodiment is
As compared with the conventional heat pipe radiator, the heat radiation performance can be much improved as shown in the results of FIG. This is a polarization plane of the heat-receiving portion 10 of the heat pipe 1 and the polarization plane of the radiating portion 11, the end view of the respective longitudinal
When one is almost horizontal over the entire length, the other is
The direction is almost 90 ° different in a state of being substantially vertical over the entire length, so that the same air does not successively contact the heat radiating portion 11, the heat diffusion plate 3, and the heat receiving plate, thereby improving the fin efficiency and reducing the ventilation resistance. This is because the temperature rise of the air passing through the heat radiating portion is smaller. Further, the heat pipe radiator of the above-described embodiment is useful when it is desired to blow air in the direction of arrow b in FIG. 2, that is, in the up and down direction in the installation state of FIG. Further, when the heat pipe type radiator is manufactured, the heat receiving portion 10 and the heat receiving plate 2 of the heat pipe 1 and the heat radiating portion 11 and the heat diffusion plate 3 are fixed to each other by the above-described method. Since the uneven plane of the heat receiving unit 10 and the heat receiving plate 2 and the uneven plane of the heat radiating unit 11 and the heat diffusion plate 3 are in close contact with each other without any gap, the heat radiation performance can be further improved.

In the heat pipe 1 of the above-described embodiment, as shown in FIG. 3, the heat receiving portion 10 and the heat radiating portion 11 whose eccentric planes are different from each other by 90 ° are continuous via the twisted portion 12. The heat receiving unit 10 and the heat radiating unit 11 may have a structure that is continuous via a cylindrical portion 13 having a predetermined length as shown in FIG. 6, for example. The heat pipe 1 of FIG. 6 is particularly useful when the strength between the heat receiving part 10 and the heat radiating part 11 requires strength.

In the heat pipe type radiator of the above-described embodiment, the radiating fins 4 have a honeycomb structure. Instead of such radiating fins having a honeycomb structure, plate-shaped or other fins may be used. it can.

[0027]

According to the heat pipe and the heat pipe type radiator of the present invention, the fin efficiency can be improved and the ventilation resistance can be reduced, and the temperature rise of the air passing through the heat radiating portion can be suppressed. The heat radiation performance is much better than the conventional one. The uneven plane of the heat receiving part and the uneven plane of the heat radiating part of the heat pipe are respectively
In the end view in the longitudinal direction, one is almost over the entire length.
When horizontal, the other is almost vertical over its entire length
Since the directions of the heat sinks are different from each other by approximately 90 °, it is useful when it is desired to blow air to the heat radiating portion of the assembled radiator in a direction orthogonal to the heat receiving plate.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a heat pipe radiator according to the present invention.

FIG. 2 is a side view of the heat pipe radiator of FIG.

FIG. 3 is a partially omitted perspective view of a heat pipe used in the radiator of FIG. 1;

4 is a partially enlarged end view of the heat pipe of FIG. 3 in which a heat receiving portion or a heat radiating portion is inserted into an insertion hole of a heat receiving plate or a heat diffusion plate.

FIG. 5 is a partially enlarged end view of a state where a heat receiving unit or a heat radiating unit is expanded from the state of FIG. 4;

FIG. 6 is a partially omitted perspective view showing another embodiment of the heat pipe according to the present invention.

FIG. 7 is a partial side view showing a state in which a conventional heat pipe radiator is attached to a substrate in an electronic device.

FIG. 8 is a front view of the heat pipe radiator of FIG. 7;

FIG. 9 is a line graph comparing the heat radiation performance of the heat pipe radiator according to the embodiment of the present invention and the conventional radiator.

[Explanation of symbols]

 1, 1 'heat pipe 10, 10' heat receiving portion 11, 11 'heat radiating portion 12 twisted portion 13 cylindrical portion 2, 2' heat receiving plate 21 leg of heat receiving plate 3, 3 'heat diffusion plate 2a, 2b, 3a, 3b Molds 4, 4 'Radiation fins 40, 40' Honeycomb-shaped holes 5 Substrate 6 Heat-generating electronic components 60 High thermal conductive rubber a, b Blowing direction

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-6-101980 (JP, A) JP-A-6-209178 (JP, A) JP-A-57-107062 (JP, A) JP-A-1- 224124 (JP, A) JP-A-5-106978 (JP, A) JP-A-4-124591 (JP, A) JP-B-63-6780 (JP, B1) JP-B-52-33346 (JP, B1) (58) Field surveyed (Int. Cl. ⁷ , DB name) F28D 15/02

Claims (5)

(57) [Claims] 1. A heat receiving portion and a heat radiating portion each having a predetermined length, each of which is formed into a flat shape , wherein one of the flat surface of the heat receiving portion and the flat surface of the heat radiating portion is one when viewed from an end face in the longitudinal direction.
Is almost horizontal over the entire length
A heat pipe characterized by being formed substantially vertically . 2. The heat pipe according to claim 1 , further comprising a cylindrical portion having a predetermined length between the heat receiving portion and the heat radiating portion. 3. A heat pipe comprising: the heat pipe according to claim 1; a heat receiving plate attached to a heat receiving portion of the heat pipe; and a heat diffusion plate attached to a heat radiating portion of the heat pipe. The portion is embedded in the heat receiving plate such that the uneven plane of the heat receiving portion is substantially parallel to both surfaces in the width direction of the heat receiving plate. A heat pipe type radiator, wherein the heat diffusion plate is embedded in the heat diffusion plate substantially in parallel with the heat diffusion plate, and radiating fins are fixed to the heat diffusion plate along the width direction. 4. The heat receiving portion is inserted into an insertion hole formed in the heat receiving plate, and the heat radiating portion is inserted into an insertion hole formed in the heat diffusion plate, respectively. The heat pipe type radiator according to claim 3, wherein both the flat surfaces are closely attached to an inner wall of each of the insertion holes. 5. The heat pipe radiator according to claim 3, wherein the heat radiation fin has a honeycomb structure in which holes extend along a width direction of the heat diffusion plate.