WO2016104728A1

WO2016104728A1 - Cooler

Info

Publication number: WO2016104728A1
Application number: PCT/JP2015/086287
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: JPWO2016104728A1; JP6448666B2

Abstract

Provided is a cooler capable of improving cooling performance and favorably maintaining cooling performance even when the orientation thereof changes during use. A tank 31 of a cooler 100 extends in the horizontal direction. A pipe 32 is slanted upward from the end connected to the tank 31 toward a closed end. The inner diameter d2 of the pipe 32 is set so as to be smaller than the inner diameter d1 of the tank 31. The center line of the pipe 32 is parallel to a radiating line extending in the radial direction from the center line of the tank 31, and is positioned upwardly eccentric relative to the radiating line in a range greater than 0 and no greater than (d1-d2)/2.

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. 2014-262357 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 there is no liquid refrigerant on the bottom surface of the tank, 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.

In addition to the inclination of the tank pipe axis, the pipe axis of the pipe placed 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, the pipe is inclined upward from a connection end to the tank toward a closed end, and an inner diameter d2 of the pipe Is set smaller than the inner diameter d1 of the tank, and the center line of the pipe is in the range of greater than 0 and less than or equal to (d1−d2) / 2 in parallel with the radial radiation from the center line of the tank. It is arranged eccentrically above the in the radiation.

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. Also, in order to demonstrate boiling cooling performance when the vehicle is climbing up and down, the refrigerant in the pipe unit is biased to one side (lower side), so that the other side (higher side) from the bottom of the tank In order to prevent the refrigerant from running out (so as not to 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 respect, in the cooler of the present invention, each pipe is inclined upward from the tank and is eccentric upward from the tank, so that the storage area for the liquid refrigerant in the tank can be increased. it can. For this reason, even when the cooler is inclined, a space can be secured between the liquid refrigerant in the tank and the pipe. Further, since the pipe is eccentric upward and the storage area in the tank is deepened, the liquid refrigerant can be held in the tank even if the attitude of the cooler changes. Therefore, the bottom of the tank does not dry, and the boiling cooling performance can be exhibited smoothly and maintained at all times.

In order to prevent the bottom of the tank from drying up due to the inclination of the vehicle, it is conceivable to shorten the length of the tank and increase the number of tanks installed accordingly, and arrange them in multiple columns. However, when the tank is shortened and arranged in multiple rows, the heat pipe structure is divided in the vehicle traveling direction, that is, the windward and leeward side of the cooling air, so that a temperature gradient occurs and the leeward side There is a concern that the temperature will rise. On the other hand, in the cooler of the present invention, each pipe is inclined upward from the tank and connected to the tank and is arranged eccentrically on the upper side of the tank. Therefore, even when the tank is elongated, The amount of liquid can be increased, and management can be performed so that the bottom of the tank does not dry up. For this reason, one long tank from the windward side to the leeward side of the cooling air can be configured, and the temperature difference between the windward and leeward can be reduced by the heat equalization characteristics of the heat pipe, so that the cooling performance can be improved. .

In the cooler of the present invention, the set liquid level of the refrigerant stored in the tank is the set liquid level 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 inner diameter d1 and the inner diameter d1 of the tank is set to be 0.27 or more.

By decentering 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 the amount of refrigerant contained in the pipe unit is increased too much, the boiling bubbles in the tank push 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). May occur.

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 satisfactorily maintained even when the posture during use is changed.
it can.

It is a side view which shows the cooler which is embodiment of this invention. It is sectional drawing of the cooler shown in FIG. 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 cross-sectional arrow view of the cooler along the AA line shown in FIG. It is principal part sectional drawing of the pipe unit in other embodiment of this invention.

Hereinafter, embodiments 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 an embodiment of the present invention. The vehicle cooler 100 is embedded in a base block 20 in which a mounting surface 21a on which the heating element 10 is mounted is formed in 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 32 connected in a standing state on the side of each tank 31, and a plurality of pipes 30 attached to these pipes 32 in a state of passing through the plurality of pipes 32. The radiating fin 40 is 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.

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.

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 erected in a row along the extending direction of the tank 31 in parallel with each other at regular intervals. As shown in FIGS. 2 and 4, each pipe 32 is disposed so as to be inclined upward at an angle α with respect to the horizontal direction from the connecting end to the tank 31 toward the closed end on the opposite side. The angle α is set with reference to an angle at which the vehicle travels on a slope and the cooler 100 may tilt (for example, 7 °). The center line of the pipe 32 is arranged in parallel with the radiation going from the center line of the tank 31 in the radial direction and is eccentric to the upper side of the radiation within the range of (d1-d2) / 2 or less. Yes. In FIG. 4, the eccentric amount of the pipe 32 is indicated by a symbol L. For example, when the inner diameter d1 of the tank 31 is 27.6 mm and the inner diameter d2 of the pipe 32 is 13.88 mm, the eccentricity L is 0 mm within the range of (d1−d2) / 2 or less. It is made into the range of 6.86 mm or less exceeding.

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 FIGS. 2 and 4, the set liquid level of the refrigerant 60 accommodated in the pipe unit 30 is set at the connection end of the pipe 32 in the 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 liquid surface and the inner diameter d1 of the tank 31 is set to be 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 FIGS. 3B and 5, the pipes 32 are arranged in a lattice shape in a top view. However, the pipes 32 may be arranged in a zigzag manner or other arrangements. .

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.

In the cooler 100 according to the present embodiment, the joint between the base block 20 and the tank 31 is fixed by soldering or the like, as shown in FIG. 1 and FIG. It is fixed by screwing to the cooling device 100 and is reinforced so as to be able to endure when the cooler 100 is subjected to severe vibration.

A plurality of thin plate-like heat radiation fins 40 made of aluminum or copper having excellent thermal conductivity are attached to the pipe 32 so as to be skewered with the pipe 32 penetrating. The heat radiating fin 40 is provided with a plurality of through holes (not shown) formed at a predetermined position of the thin plate by, for example, burring. By press-fitting the pipes 32 into these through holes, the radiation fins 40 are attached to the pipes 32 so that the radiation 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 cooler 100 configured as described above, the heat generated from the heating element 10 is transmitted to the base block 20 and further transmitted from the base block 20 to the tank 31 of the pipe unit 30 to boil the refrigerant 60 in the tank 31. Let it 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 the cooler 100, the pipe unit 30 is configured such that each pipe 32 is inclined upward from the tank 31. Therefore, when the vehicle travels on a sloped place and the cooler 100 tilts, The pipe 32 can maintain an attitude at an angle greater than horizontal. Moreover, since each pipe 32 is eccentrically arranged on the upper side with respect to the tank 31, the storage area of the liquid refrigerant 60 in the tank 31 can be increased. As a result, even when the cooler 100 is tilted and its posture is changed, a space can be secured in the tank 31 while holding the liquid refrigerant 60 in the tank 31, and the refrigerant 60 remains in liquid form from the tank 31 to the pipe 32. Inflow can be prevented. That is, since the liquid refrigerant 60 is prevented from flowing into the pipe 32 and the bottom of the tank 31 is not dried, the boiling cooling performance can be exhibited smoothly at all times, and the cooling performance can be maintained well. it can.

In the cooler 100, even when the tank 31 is elongated, the bottom of the tank 31 can be managed not to dry up by increasing the amount of the refrigerant 60 accommodated in the pipe unit 30. For this reason, the tank 31 is lengthened and unified, and the temperature difference between the windward and leeward can be reduced by the heat equalization characteristics of the heat pipe, and the cooling performance can be improved.

In the cooler 100, the maximum opening height m2 of the connection end of the pipe 32 and the inner diameter d1 of the tank 31 in the state where the set liquid level of the refrigerant 60 is left in the horizontal direction along the extending direction of the tank 31. The ratio (m2 / d1) is set to be equal to or greater than 0.27 and the vapor passage is secured, so that it is possible to prevent 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.

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 embodiment, although each pipe 32 is cut | disconnected in the connection end so as to be orthogonal to the centerline of each pipe 32 as shown in FIG. 4, like the pipe unit 30A shown in FIG. You may use the pipe 32A which has the connection end cut | disconnected diagonally with respect to the centerline. In this case, the amount of entry of the connection end of the pipe 32A into the tank 31 can be reduced as much as possible.

∙ Provide a cooler that can improve cooling performance and maintain good boiling cooling performance even when the posture during use changes.

DESCRIPTION OF SYMBOLS 10 Heat generating body 20 Base block 21a Mounting surface 21b Opposite

surface

30, 30A Pipe unit 31

Tank

32, 32A Pipe 40 Radiation fin 50 Fixing metal 60 Refrigerant 100 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 in a horizontal direction;
The pipe is inclined so as to go upward from the connection end with the tank toward the closed end,
An inner diameter d2 of the pipe is set smaller than an inner diameter d1 of the tank,
The center line of the pipe is arranged in parallel with the radial radiation from the center line of the tank and eccentrically above the radiation within a range greater than 0 (d1-d2) / 2. The cooler.
The set liquid level of the refrigerant stored in the tank is in a state where the extending direction of the tank is allowed to stand 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 described.