WO2016104729A1

WO2016104729A1 - Cooler

Info

Publication number: WO2016104729A1
Application number: PCT/JP2015/086288
Authority: WO
Inventors: 靖人末木; 俊一佐田; 季朗久野
Original assignee: 三菱アルミニウム株式会社
Priority date: 2014-12-25
Filing date: 2015-12-25
Publication date: 2016-06-30
Also published as: JPWO2016104729A1; JP6505130B2

Abstract

Provided is a cooler capable of improving cooling performance and favorably maintaining cooling performance even when the orientation thereof during use changes. A tank 31 of a cooler 100 extends in the horizontal direction. A pipe 32 has a base end section 33 having a connecting end connected to the tank 31, and a heat-dissipating section 34 curving from the base end section 33 and having a blocked end on the tip side thereof. The base end section 33 is slanted upward from the connecting end 32j at a prescribed first slant angle α relative to the horizontal direction. The heat-dissipating section 34 is positioned higher than a set fluid level for a coolant 60 stored in the tank 31, and is provided at a second slant angle which, relative to the horizontal direction, is equal to or greater than 0° and less than the first slant angle α of the base end section 33.

Description

Cooler

The present invention relates to a construction machine (hybrid), a wind power / solar power generation power converter, a power converter such as a power supply / uninterruptible power supply, a so-called inverter for motor control of an elevator / rolling machine / machine tool, etc., railway The present invention relates to a cooler used for cooling a control device using a semiconductor element such as a power transistor or a thyristor of a vehicle or an electric vehicle.
This application claims priority based on Japanese Patent Application No. 2014-262358 for which it applied on December 25, 2014, and uses the content here.

As a cooler used for cooling control devices using semiconductor elements such as power transistors and thyristors, a cooler (boiling cooler) that cools a heating element using latent heat when the refrigerant boils is known. Yes.

For example, a cooler (heat pipe cooler) described in Patent Document 1 embeds a plurality of circular tanks having a large cross-sectional area in a base block that receives heat from a heating element such as a semiconductor element. A plurality of thin pipes are erected on the side surface of the exposed portion, and a plurality of fins are attached to the pipes, so that the heat of the heating element can be cooled by outside air.

JP 2004-125381 A

In order to exhibit boiling cooling performance, it is necessary to secure an appropriate space in the tank containing the refrigerant and to connect a pipe to this space portion. Ideally, this space is usually 1/3 or more of the volume of the tank. On the other hand, if the liquid refrigerant is not in contact with the bottom surface of the tank, the boiling cooling performance cannot be exhibited.

In the cooler described in Patent Document 1, a plurality of pipes are installed upright with respect to the side surface of the base block. When a vehicle equipped with this cooler travels on a slope, the tank space is partially filled with liquid refrigerant in the axial direction of the tank tube, and the refrigerant reaches the pipes in the liquid state. The problem was that there was no liquid refrigerant at the bottom.

Also, apart from the inclination of the tank tube axis, the tube axis of the pipe installed upright in the tank may be inclined. In this case, not only does the refrigerant enter the pipe in a liquid state and the condensation area decreases, but the cooling performance may decrease, and the boiling bubbles violently collide with the tip of the pipe, causing a boiling sound (impact sound). ) May occur.

The present invention has been made in view of such circumstances, and can provide a cooler that can improve cooling performance and can maintain good cooling performance even when the posture during use changes. With the goal.

The cooler of the present invention includes a base block having a mounting surface on which a heating element is mounted along the vertical direction; a circular tank embedded in a surface opposite to the mounting surface of the base block and containing a refrigerant; And a plurality of parallel pipe pipes connected in a standing manner to the side of the tank; and a plurality of heat radiations attached to the pipes through the pipes. The tank extends in a horizontal direction, and the pipe has a base end portion having a connection end connected to the tank; and bends from the base end portion and closes to the tip end side A heat dissipating part having an end; and the base end part is inclined upward from the connection end at a predetermined first inclination angle with respect to a horizontal direction, and the heat dissipating part is 0 with respect to the horizontal direction. And the first end of the base end Provided at a second inclination angle of less than oblique angle, to the tank, the set liquid level of the coolant is set at a position lower than the radiator portion.

Usually, in a thermosiphon type heat pipe (pipe unit) in which a plurality of pipes are connected to one tank, the condensation area of the plurality of pipes is larger than that of a single pipe type heat pipe, so that it is accommodated in the pipe unit. The amount of refrigerant is large. In addition, in order to demonstrate the boiling cooling performance at the time of a gradient accompanying the climbing of the vehicle, the refrigerant in the pipe unit is biased to one side (lower side), so that there is no refrigerant from the bottom of the tank on the opposite side (higher side). In order to prevent this from happening (so that it does not dry up), it is necessary to increase the amount of refrigerant stored in the pipe unit. However, on the other hand, in order to exert the boiling cooling performance, it is also possible to secure an appropriate space between the refrigerant (liquid level of the refrigerant) accommodated in the pipe unit and the pipe attached to the tank. Since it is required, it may be disadvantageous that the amount of the refrigerant is large.

In this regard, in the cooler of the present invention, each pipe is inclined to the upper side from the tank and connected to the tank and bent in the middle, so that the heat radiating part of the pipe is located above the tank. Therefore, the refrigerant storage area in the tank can be increased. For this reason, even when the cooler tilts and changes its posture, it is possible to secure a space between the tank and the heat radiating portion of the pipe and prevent the refrigerant from flowing from the tank to the heat radiating portion of the pipe in a liquid state. Also, with such a configuration, a sufficient amount of refrigerant can be held in the tank, so that the bottom of the tank does not dry. Further, since the pipe is bent between the base end portion and the heat radiating portion, even if the liquid refrigerant enters the base end portion, the bent portion becomes a resistance and hardly flows into the heat radiating portion. Accordingly, it is possible to increase the amount of the refrigerant stored in the tank while suppressing the flow of the liquid refrigerant from the tank to the heat radiating portion of the pipe. be able to.

In the cooler of the present invention, the heat radiating portion of the pipe has the second inclination angle of 0 °, and the heat radiating fin is attached to the heat radiating portion of the pipe so that a plane direction thereof is along the vertical direction. ing.

Since the heat dissipating fins are arranged so that the plane direction is in the vertical direction, that is, parallel to the base block, the heat dissipating fins are parallel to the natural convection direction (vertical direction) of air when used in natural air cooling. become. For this reason, resistance to natural convection can be reduced, and cooling performance can be improved.

In the cooler of the present invention, the set liquid level of the refrigerant accommodated in the tank is set at the connection end of the pipe in a state where the extending direction of the tank is left in a horizontal direction. The ratio (m2 / d1) between the maximum opening height m2 exposed from the surface and the inner diameter d1 of the tank is set to be 0.27 or more.

By decentering the heat radiating part of the pipe upward with respect to the tank, it is possible to increase the amount of refrigerant accommodated in the pipe unit, and to improve the cooling performance. However, if too much refrigerant is stored inside the pipe unit, the boiling bubbles in the tank push up the refrigerant toward the pipe, causing the boiling bubbles to collide violently at the tip of the pipe, resulting in a boiling sound (collision sound). There is.

In this regard, the present inventor has found that the liquid level of the refrigerant accommodated in the pipe unit is left standing along the horizontal direction of the tank extending direction and the maximum opening height m2 of the pipe connection end and the tank It was found that the generation of boiling noise can be avoided by setting the ratio (m2 / d1) to the inner diameter d1 to be 0.27 or more. As described above, when the ratio (m2 / d1) is set to 0.27 or more, a steam passage is ensured between the tank and the pipe, so that boiling bubbles can be prevented from pushing up the refrigerant. Therefore, even when the amount of the refrigerant stored in the pipe unit is increased, generation of boiling noise can be avoided.

According to the present invention, the cooling performance can be improved, and the cooling performance can be maintained well even when the posture during use is changed.

It is a side view which shows the cooler which is 1st Embodiment of this invention. FIG. 2 is a partial cross-sectional arrow view of the cooler shown in FIG. 1 taken along line II-II in FIG. 3B. It is a front view of the cooler shown in FIG. It is a rear view of the cooler shown in FIG. It is principal part sectional drawing in the connection part of the tank and pipe of a pipe unit. It is a fragmentary sectional arrow view which shows the cooler which is 2nd Embodiment of this invention.

Hereinafter, each embodiment of the cooler of the present invention will be described with reference to the drawings.
1 to 3A and 3B show a cooler 100 according to a first embodiment of the present invention. The cooler 100 is embedded in a base block 20 in which a mounting surface 21a to which the heating element 10 is mounted is formed along the vertical direction, and an opposite surface 21b opposite to the mounting surface 21a of the base block 20. A plurality of tanks 31 and a plurality of pipes 30 connected to each tank 31 in a standing state, and a plurality of heat radiations attached to these pipes 32 with the plurality of pipes 32 penetrating. The fin 40 is provided and used for a vehicle.

Although not shown, the cooler 100 is installed in the lower part of the side surface of the vehicle so that the mounting surface 21a of the base block 20 is along the vertical direction.

The base block 20 is formed of a metal having a high heat capacity and excellent heat conductivity such as aluminum and copper. A heating element 10 such as a semiconductor element is mounted on the mounting surface 21a on one side (left side in FIG. 1) of the base block 20, and the side opposite to the mounting surface 21a on which the heating element 10 is mounted (right side in FIG. 1). The tank 31 is embedded in the opposite surface 21b.

The pipe unit 30 is configured by connecting a plurality of thin tubular pipes 32 having an inner diameter d2 smaller in diameter than the inner diameter d1 of the tank 31 to the side surface of the tubular tank 31. For example, a tank 31 having an inner diameter d1 of 27.6 mm and a pipe 32 having an inner diameter d2 of 13.88 mm can be suitably used.

The tank 31 and the pipe 32 are made of aluminum or copper, and are joined together by brazing with the internal space integrated. A refrigerant 60 such as pure water or perfluorocarbon is accommodated in the pipe unit 30 formed by joining the tank 31 and each pipe 32.

As shown in FIG. 2, the tank 31 is formed of a circular pipe, the extending direction thereof is arranged along the horizontal direction, and the tank 31 is attached to the opposite surface 21 b of the base block 20. Note that FIG. 2 shows a cross section only in the vicinity of the joint portion between the base block 20 and the tank 31 and the base end portion 33 of the pipe 32, and shows side surfaces of the heat radiating portions 34 and the heat radiating fins 40 of the pipe 32.

As described above, the pipe 32 has the inner diameter d2 set smaller than the inner diameter d1 of the tank 31, and is connected to the side surface of each tank 31 as shown in FIG. Further, as shown in FIG. 3B, the pipes 32 are arranged in a state where they are erected in parallel (in one row) with a certain interval in the extending direction of the tank 31. As shown in FIGS. 2 and 4, each pipe 32 is formed by bending a base end portion 33 connected to the tank 31 and a heat radiating portion 34 on the front end side of the base end portion 33 by bending. . The base end portion 33 is inclined at a predetermined first inclination angle α (> 0 °) upward from the connection end 32j with the tank 31 with respect to the horizontal direction. The heat radiating portion 34 provided continuously to the base end portion 33 is inclined at a second inclination angle of 0 ° or more and less than the first inclination angle α with respect to the horizontal direction, and is accommodated in the tank 31. It is disposed at a position higher than the set liquid level of the refrigerant 60. In the cooler 100 of the present embodiment, as shown in FIGS. 2 and 4, the heat radiating portion 34 of the pipe 32 is disposed along the horizontal direction toward the closed end 32 b, that is, at a second inclination angle of 0 °, The center line is eccentric above the center line of the tank 31.

The first inclination angle α is set with reference to a possible angle when the vehicle is traveling on a slope and the cooler 100 is inclined (for example, 7 °). In the cooler 100 of the present embodiment shown in FIGS. 1 to 4, the first inclination angle α is set to 30 °, and the heat radiation part 34 of the pipe 32 is higher than the set liquid level of the refrigerant 60 by the distance S. Placed in position.

As shown in FIGS. 2 and 4, the set liquid level of the refrigerant 60 accommodated in the pipe unit 30 is at the connection end 32 j of the pipe 32 in a state where the extending direction of the tank 31 is left along the horizontal direction. The ratio (m2 / d1) between the maximum opening height m2 exposed from the set liquid surface and the inner diameter d1 of the tank 31 is set to 0.27 or more.

In the cooler 100, as shown in FIGS. 1 to 3A and 3B, a plurality of tanks 31 (pipe units 30) to which a plurality of pipes 32 are attached in this manner are vertically arranged on the opposite surface 21b of the base block 20. The pipes 32 are arranged in a matrix by arranging them in parallel. In this embodiment, as shown in FIG. 3B, the pipes 32 are arranged in a lattice shape in a top view, but a configuration in which the pipes are arranged in a zigzag pattern or other arrangements are possible.

The base block 20 and each tank 31 are joined together by soldering or the like. Thereby, the heat transfer between the base block 32 and the tank 31 is performed smoothly.

A plurality of thin plate-like heat radiating fins 40 made of aluminum or copper having excellent thermal conductivity are attached to the heat radiating portion 34 of the pipe 32 so as to be skewered with the pipe 32 penetrating. ing. The heat radiation fins 40 are arranged such that the plane direction thereof is in the vertical direction. These radiating fins 40 are provided with a plurality of through holes (not shown) formed at a predetermined position of the thin plate, for example, by burring or the like. By press-fitting the heat radiating portion 34 of the pipe 32 into these through holes, the heat radiating fins 40 are attached to the pipes 32 so that the heat radiating fins 40 and the pipes 32 are integrally provided. In addition, the heat radiation fin 40 can also be attached by expanding the pipe 32 inserted into the through hole of the heat radiation fin 40.

In the vehicle cooler 100 configured as described above, the heat generated from the heating element 10 is transmitted to the base block 20, further transmitted from the base block 20 to the tank 31 of the pipe unit 30, and the refrigerant 60 in the tank 31. Boil and evaporate. Then, the vapor of the evaporated refrigerant 60 rises in the tank 31 and moves into the pipe 32, and is cooled by transferring heat to the radiating fins 40 through the pipe 32.

In this cooler 100, the base end portion 33 of each pipe 32 is inclined upward and connected to the tank 31, so that the heat radiating portion 34 of the pipe 32 is eccentric to the upper side of the tank 31. The storage area of the refrigerant 60 inside can be increased. Further, the base end portion 33 of the pipe 32 inclined at the first inclination angle α in this way has a posture at an angle higher than the horizontal even when the vehicle travels on a sloped place and the cooler 100 tilts. Can keep. Thereby, even when the cooler 100 is tilted and the posture is changed, a space is secured between the tank 31 and the pipe 32, and the refrigerant 60 can be prevented from flowing from the tank 31 into the pipe 32 in a liquid state. For this reason, in the cooler 100, while suppressing the flow of the liquid refrigerant 60 from the tank 31 to the pipe 32, the amount of the refrigerant 60 stored in the tank 31 is increased and the refrigerant 60 is held in the tank 31. As a result, the bottom of the tank 31 does not dry. Therefore, the cooling performance can be exhibited smoothly at all times, and the cooling performance can be maintained satisfactorily.

In the cooler 100, the heat radiating portion 34 of the pipe 32 extends along the horizontal direction, and the plane direction of the heat radiating fins 40 is arranged along the vertical direction, that is, parallel to the base block 20. Thus, the heat radiation fins 40 are parallel to the air flow direction (that is, the extending direction of the tank 31) by the vehicle traveling and to the natural convection direction (the direction of the arrow C) when used in natural air cooling. Can be arranged in parallel. For this reason, even when the vehicle is stopped, the resistance to natural convection can be reduced, and the cooling performance can be improved.

In the cooler 100, the maximum opening height m <b> 2 of the connection end 32 j of the pipe 32 and the tank 31 are set in a state where the set liquid level of the refrigerant 60 is left stationary along the horizontal direction of the tank 31. Since the ratio (m2 / d1) to the inner diameter d1 is set to be 0.27 or more and the vapor passage is secured, it is possible to prevent the boiling bubbles from pushing up the liquid refrigerant 60. Therefore, even when the amount of the refrigerant 60 accommodated in the pipe unit 30 is increased, generation of boiling noise can be avoided.

FIG. 5 shows a cooler 110 according to the second embodiment of the present invention. Each pipe 132 constituting the pipe unit 130 of the cooler 110 is formed by bending a base end portion 133 connected to the tank 31 and a heat radiating portion 134 on the front end side of the base end portion 133 by bending. ing. Similarly to the first embodiment, the base end portion 133 is connected to the tank 31 while being inclined upward at a predetermined first inclination angle α with respect to the horizontal direction. The heat dissipating part 134 is provided to be inclined upward at a second inclination angle that is greater than 0 ° and smaller than the first inclination angle α with respect to the horizontal direction. Further, the heat radiating fins 140 are fixed to the heat radiating portion 134 with a slight inclination from the vertical direction. FIG. 5 shows a cross section only in the vicinity of the joint portion between the base block 20 and the tank 31 and the base end portion 133 of the pipe 132, and the heat radiating portions 134 and the heat radiating fins 140 of the pipe 132 are shown as side surfaces.

In this case, since the heat radiating portion 134 is inclined, in order to obtain sufficient cooling efficiency for the arrangement space, the heat radiating portion 134 has two types of heat radiating fins 140 (401, 402) having different sizes and heat radiating portions 134 having different lengths. Three types of pipes 132 (301, 302, 303) are required. In addition, since the radiating fins 140 are not parallel to the natural convection direction C of air, the resistance is large compared to the first embodiment. However, since the heat radiating part 134 is inclined, it is difficult for the refrigerant to flow into the heat radiating part 134 in a liquid state, and it is possible to more effectively prevent the cooling performance from being reduced due to the reduction of the condensation area and the generation of noise due to boiling bubbles.

Note that the present invention is not limited to the configuration of the above-described embodiment, and various modifications can be made in the detailed configuration without departing from the spirit of the present invention.

For example, the radiating fin 40 is configured to be attached in a state in which all the pipes 32 are penetrated as in the above embodiment, and the plurality of pipes 32 are divided into several blocks, and each of the plurality of pipes 32 is divided. It can also be set as the structure which attaches the small radiation fin divided into.

Moreover, in the said 1st Embodiment, although the extending direction of the thermal radiation part 34 of the pipe 32 was arrange | positioned along the horizontal direction, the extending direction of a thermal radiation part is other than a horizontal direction (angle 0 degree). For example, as in the second embodiment, the base end portion 33 may be inclined at an angle less than the first inclination angle α with respect to the horizontal direction.

In the cooler, the cooling performance can be improved, and the cooling performance can be maintained well even when the posture during use changes.

DESCRIPTION OF SYMBOLS 10 Heat generating body 20 Base block 21a Mounting surface 21b Opposite surface 30,130 Pipe unit 31 Tank 32,132 (301-303) Pipe 32b Closed end 32j Connection end 33,133 Base end part 34,134 Radiation part 40,140 (401 402) Radiating fin 60

Refrigerant

100, 110 Cooler

Claims

A base block having a mounting surface on which a heating element is mounted along the vertical direction;
A tubular tank embedded in a surface opposite to the mounting surface of the base block and containing a refrigerant; and a plurality of parallel tubular pipes connected in a standing state to a side surface of the tank; A pipe unit consisting of
A plurality of heat dissipating fins attached to these pipes in a state of penetrating the plurality of pipes;
The tank extends along a horizontal direction;
The pipe has a base end portion having a connection end connected to the tank; and a heat dissipation portion bent from the base end portion and having a closed end on the tip end side,
The base end portion is inclined upward from the connection end at a predetermined first inclination angle with respect to a horizontal direction,
The heat dissipating part is provided at a second inclination angle of 0 ° or more with respect to the horizontal direction and less than the first inclination angle of the base end part,
The cooler, wherein a set liquid level of the refrigerant is set at a position lower than the heat radiating portion in the tank.
The heat radiating portion of the pipe has the second inclination angle of 0 °,
The cooler according to claim 1, wherein the heat radiation fin is attached to the heat radiation portion of the pipe so that a planar direction thereof is along the vertical direction.
The set liquid level of the refrigerant stored in the tank is
In the state where the extending direction of the tank is left along the horizontal direction,
The ratio (m2 / d1) between the maximum opening height m2 exposed from the set liquid level at the connection end of the pipe and the inner diameter d1 of the tank is set to be 0.27 or more. The cooler according to claim 1.