JP2002031454A - Cooling apparatus with boiling - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure a stable radiation performance even when an apparatus is used in a state of slanting to either of the right and left sides. SOLUTION: Radiators 4 are provided respectively on both sides of the right and the left of a refrigerant vessel 3 and the respective lower tanks 7 of the radiators 4 on the right and left sides are made to communicate with each other through the refrigerant vessel 3 (passage part). The vapor of a refrigerant boiling in the refrigerant vessel 3 flows in both directions to the right and the left through a vapor outflow passage and can run into the lower tanks 7. This cooling apparatus 1 with boiling is disposed, for instance, with the lengthwise direction of the refrigerant vessel 3 directed to the longitudinal direction of an automobile and the refrigerant vessel 3 is mounted in a horizontal state. When the automobile runs on a sloping road or the like, in this case, the refrigerant vessel 3 tilts to a horizontal plane. Since the radiators 4 are provided on both sides of the right and the left, however, the refrigerant vapor can be brought into heat exchange with cooling water for heat radiation at least in either of the radiators 4, even when the vessel is used in a state wherein a height difference occurs between the radiators 4 on the opposite sides. Therefore the radiating performance does not deteriorate and the stable radiating performance can be ensured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boiling cooling device for cooling a heating element by transferring boiling heat of a refrigerant.

[0002]

2. Description of the Related Art As a prior art, for example, Japanese Patent Laid-Open
There is a boiling cooling device disclosed in US Pat. This boiling cooling device cools a heating element mounted on an electric vehicle (for example, an IGBT module of a traveling inverter). As shown in FIG. 14, a refrigerant tank 100 for storing a liquid refrigerant and a heating element 110 are provided. A radiator 120 for exchanging heat with the atmosphere of the refrigerant vapor that has been boiled and vaporized by receiving heat, and dissipating heat.
00 is inclined.

[0003]

However, the above-mentioned boiling cooling device has a problem in that it is difficult to mount the refrigerant tank 100 on the vehicle due to restrictions on the mounting on the vehicle.
When is installed so as to be in a substantially horizontal state, the front end side (the side opposite to the radiator 120) of the refrigerant tank 100 becomes higher when traveling on a slope or the like, and is inclined to the side opposite to the state shown in FIG. In this case, since the refrigerant vapor generated in the refrigerant tank 100 stays in the refrigerant tank 100 and cannot rise to the radiator 120 side, there is a problem that heat radiation performance is reduced. The present invention has been made based on the above circumstances, and an object of the present invention is to provide a boiling cooling device that can secure stable heat radiation performance even when used in a state of being inclined to the left or right side.

[0004]

A boiling cooling device according to the present invention includes a refrigerant container and a radiator, and the refrigerant container boils by receiving heat from a heating element. It has a vapor outflow passage through which refrigerant vapor can flow out of the boiling portion in both left and right directions, and radiators are provided on both left and right sides of the refrigerant container. According to this configuration, when the boiling cooling device is inclined, for example, when the right side is higher than the left side of the refrigerant container, the refrigerant vapor that has boiled due to the heat of the heating element flows out rightward from the boiling portion in the refrigerant container. Ascends the path and flows into the radiator provided on the right side of the refrigerant container. Conversely, when the left side is higher than the right side of the refrigerant container, the refrigerant vapor boiling due to the heat of the heating element rises along the vapor outflow path from the boiling portion in the refrigerant container to the left, and is provided on the left side of the refrigerant container. Into the heatsink. As a result, at least one of the radiators allows the refrigerant vapor to exchange heat with the external fluid to radiate heat, so that even when the boiling cooling device is used in a state inclined to the left or right, the heat radiation performance does not decrease, It is possible to secure stable heat radiation performance.

According to a second aspect of the present invention, in the boiling cooling apparatus according to the first aspect, the refrigerant container has a liquid return passage into which the condensed liquid liquefied by the radiator flows. It has a lower tank that communicates with the return passage, and a heat exchange unit that exchanges heat between the refrigerant vapor and the external fluid is provided above the lower tank. For example, when the right side of the refrigerant container rises higher than the left side of the refrigerant container due to tilting of the boiling cooling device, the refrigerant vapor boiling in the refrigerant container flows into the right radiator, and the condensed liquid liquefied by the right radiator becomes the right radiator. Flows from the lower tank into the liquid return passage, and flows into the lower tank of the radiator on the left through the liquid return passage. In the lower tank, the vapor outflow passage and the liquid return passage communicate with each other, so that the condensate flowing into the lower tank from the liquid return passage can flow into the vapor outflow passage and return to the boiling portion.

(Means of Claim 3) The boiling cooling device according to Claim 1 or 2 is used by being mounted on an automobile.
Automobiles may change their posture during traveling significantly (for example, when traveling on a slope, the inclination in the front-rear direction becomes larger than when traveling on flat ground), but the boiling cooling device of the present invention If used, stable heat radiation performance can be obtained regardless of the change in the attitude of the automobile.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a cooling apparatus according to the present invention will be described with reference to the drawings. 1 to 3 show the appearance of the boiling cooling device, FIG. 1 is a front view of the boiling cooling device, FIG. 2 is a bottom view of the boiling cooling device (a plan view as viewed from the mounting surface side of the heating element), and FIG. It is a side view (top view seen from the side of the heat radiation part) of a boiling cooling device. The boiling cooling device 1 of the present embodiment is used, for example, mounted on an electric vehicle, and cools an IGBT module (the heating element 2 of the present invention) that forms an inverter circuit of a traveling motor. This boiling cooling device 1
Has a refrigerant container 3 for storing a liquid refrigerant therein, and a radiator 4 for cooling the refrigerant vapor boiling by receiving the heat of the heating element 2 in the refrigerant container 3 as shown in FIGS. And it is provided using a metal material having a high thermal conductivity (for example, aluminum).

The refrigerant container 3 is a thin hollow body having a small thickness (height) in the vertical direction and a large thickness in the plane direction (width direction and length direction), and has both ends in the length direction (left and right directions in FIG. 1). Both are open and the inside is divided into a plurality of passages. In addition, an inner fin 5 is inserted into at least a passage portion (hereinafter, referred to as a steam outflow passage 3a) included in a range (a boiling portion) where the heating element 2 is attached (see FIG. 4). The inner fin 5 may be provided with a plurality of recesses 5a, for example, as shown in FIG. 5A or 5B, to increase the heat transfer area (boiling area). The heating element 2
The refrigerant container 3 is fixed to the lower surface of the refrigerant container 3 with bolts 6.

The radiator 4 includes a set of tanks (the lower tank 7).
And an upper tank 8) and a heat exchange section (described below), and are provided on both left and right sides of the refrigerant container 3 as shown in FIG. The lower tank 7 is provided in communication with the passage of the refrigerant container 3, and stores the liquid refrigerant together with the refrigerant container 3. Therefore, the right radiator 4 and the left radiator 4
The lower tanks 7 communicate with each other through the refrigerant container 3 (passage portion), and the refrigerant vapor boiling in the refrigerant container 3 can flow in the left and right directions through the vapor outflow passage 3 a and flow into the lower tank 7. . Note that the liquid refrigerant is contained up to a position higher than the upper surface of the refrigerant container 3 (see FIG. 4). That is, the inside of the refrigerant container 3 is filled with the liquid refrigerant.

A coolant flow control plate 9 is provided inside the lower tank 7, as shown in FIGS. The refrigerant flow control plate 9 controls the flow of the vapor into the lower tank 7 so that the refrigerant vapor flowing out from the vapor outflow passage 3a of the refrigerant container 3 and the condensate flowing back from the radiator 4 do not interfere in the lower tank 7. An extension passage portion 9a for extending the road 3a is formed (FIG. 1).
1). The upper tank 8 is located above the heat exchange section,
The heat exchanger is provided so as to face the lower tank 7 in the vertical direction via the heat exchange unit.

As shown in FIG. 4, the heat exchange section includes a plurality of heat radiation passages 10 communicating the lower tank 7 and the upper tank 8,
Water jacket 11 provided around heat radiation passage 10
The heat exchange is performed between the refrigerant vapor flowing through the heat radiation passage 10 and the cooling water flowing through the water jacket 11. As shown in FIG. 6, the heat radiation passages 10 are opened in an elongated rectangular shape in cross section, and are arranged side by side at substantially constant intervals in the width direction of the two tanks 7 and 8 (the left-right direction in FIG. 6).

As shown in FIG. 7, an inner fin 12 is inserted into the heat radiation passage 10. The inner fin 12 is formed by alternately bending a thin metal plate of, for example, aluminum at a predetermined pitch to form a wavy shape, and is inserted in the heat radiation passage 10 in one direction (rightward in FIG. 7). As a result, the inside of the heat radiation passage 10 has a first passage portion (hereinafter, referred to as a steam passage portion 10 a) generated on the other end side of the inner fin 12 and a second passage portion formed between the pitches of the inner fins 12. Hereinafter, it is referred to as a liquid passage portion 10b).

The water jacket 11 is a passage for flowing cooling water. As shown in FIGS. 6 to 8, the water jacket 11 is provided so as to surround the periphery of each heat radiation passage 10 and the entire periphery of the heat exchange section. It is connected to a circulating cooling water circuit. Fig. 1
As shown in FIG. 0, a pump 14 for circulating cooling water and a radiator 1 for cooling the cooling water with air are used for a water cooling system for cooling a running motor 13 of an electric vehicle with water.
5 and so on.

Next, the operation of this embodiment will be described. The liquid refrigerant stored in the refrigerant container 3 is boiled by receiving the heat of the heating element 2 and passes through the extension passage portion 9a formed by the refrigerant flow control plate 9 from the vapor outflow passage 3a as shown in FIG. To flow into the lower tank 7. Thereafter, the liquid flows from the lower tank 7 into the steam passage portion 10a in the heat radiation passage 10, rises up the steam passage portion 10a and flows into the upper tank 8, and further, each liquid formed between the upper tank 8 and the pitch of the inner fins 12 is formed. It flows into the passage 10b. Here, the liquid passage 1
The refrigerant vapor flowing into Ob is cooled by the cooling water flowing through the water jacket 11 and condensed and liquefied on the surface of the inner fin 12 and the inner wall surface of the heat radiation passage 10.

The condensed liquid liquefied in the liquid passage 10b is held below the inner fin 12 by surface tension,
As shown in (1), a liquid pool is formed. Since the liquid reservoir is formed below the inner fin 12, the refrigerant vapor rising from the lower tank 7 is supplied to the liquid passage 10b.
Into the heat radiation passage 10 and a good refrigerant circulation flow can be formed in the heat radiation passage 10. The condensed liquid accumulated in the liquid pool is sequentially dropped from the liquid pool into the lower tank 7 by the pressure of the refrigerant vapor rising in the vapor passage 10a.

The boiling cooling device 1 includes, for example, a refrigerant container 3
Are arranged with the longitudinal direction (the left-right direction in FIG. 1) facing the front-rear direction of the vehicle, and the refrigerant container 3 is mounted in a horizontal state. In this case, when the automobile runs on a slope or the like, the refrigerant container 3 is inclined with respect to the horizontal plane. Therefore, for example, FIG.
As shown in FIG. 2, when the right side of the refrigerant container 3 becomes higher than the left side, the refrigerant vapor boiling in the refrigerant container 3 rises upward (to the right) from the boiling portion along the inclination of the refrigerant container 3 and moves to the right. It flows into the lower tank 7 of the radiator 4.

After that, as described above, the condensed liquid cooled by the radiator 4 drops into the lower tank 7. At this time, the condensed liquid dropped into the lower tank 7 from the liquid reservoir mainly flows into the passage portion (referred to as a liquid return passage 3b) in the refrigerant container 3 from both outer sides of the refrigerant flow control plate 9 (FIG. 13). reference). The condensed liquid that has flowed into the liquid return passage 3b flows into the lower tank 7 of the radiator 4 on the left along the inclination of the refrigerant container 3 as it is, and returns from the lower tank 7 to the boiling portion in the refrigerant container 3 again. be able to.

(Effects of the present embodiment) Since the radiators 4 are provided on the left and right sides of the refrigerant container 3 in the boiling cooling device 1 of the present embodiment, the radiators 4 on both sides are used in a state where a difference in elevation occurs. However, since at least one of the radiators 4 can exchange the refrigerant vapor with the cooling water to radiate heat, the heat radiation performance does not decrease and stable heat radiation performance can be ensured. In particular, when the boiling cooling device 1 is used by being mounted on an automobile, the attitude of the automobile is not constant. For example, the direction in which the refrigerant container 3 inclines when traveling uphill and traveling downhill. Since the opposite is true, the boiling cooling device 1 of the present embodiment, which can secure stable heat radiation performance regardless of which side is inclined, is extremely effective.

The boiling cooling device 1 of the present invention is not limited to the case where it is mounted on an automobile and used, for example, mounted on a transport means such as a ship (especially a small ship with a large swing) or a helicopter. You can also. Alternatively, it may be used on a slope. Further, the radiator 4 has a water cooling structure by providing the water jacket 11 in the heat exchange section, but may have an air cooling structure in which the refrigerant vapor is cooled by outside air.

[Brief description of the drawings]

FIG. 1 is a front view of a boiling cooling device.

FIG. 2 is a top view of the boiling cooling device.

FIG. 3 is a side view of the boiling cooling device.

FIG. 4 is a sectional view taken along line AA of FIG. 1;

FIG. 5 is a cross-sectional view of the refrigerant container showing an attached state of the inner fin.

FIG. 6 is a sectional view taken along line BB of FIG. 3;

FIG. 7 is a sectional view taken along the line CC of FIG. 3;

FIG. 8 is a sectional view taken along line DD of FIG. 3;

FIG. 9 is a sectional view taken along line EE of FIG. 3;

FIG. 10 is a cooling water circuit diagram of the water cooling system.

FIG. 11 is a sectional view taken along line FF of FIG. 9;

FIG. 12 is a front view of the boiling cooling device showing a state where the refrigerant container is inclined.

FIG. 13 is a sectional view taken along line GG of FIG. 9;

FIG. 14 is a drawing showing an example of use of a boiling cooling device (prior art).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Boiling cooling device 2 Heating element 3 Refrigerant container 3a Vapor outflow path 3b Liquid return path 4 Radiator 7 Lower tank 10 Radiation path (heat exchange part) 11 Water jacket (heat exchange part)

Claims (3)

[Claims] 1. A boiling cooling device for cooling a heating element by transferring heat of boiling of a refrigerant, comprising: a refrigerant container for storing a liquid refrigerant therein and transmitting heat of the heating element to the liquid refrigerant; And a radiator that cools the refrigerant vapor by heat exchange with an external fluid.The refrigerant container receives the heat of the heat generating element, and the liquid refrigerant receives the heat of the heat generating element. A boiling cooling device, comprising: a vapor outflow passage through which refrigerant vapor can flow out of a boiling portion in which refrigerant vapor flows in both left and right directions, wherein the radiators are provided on both left and right sides of the refrigerant container. 2. The boiling cooling device according to claim 1, wherein the refrigerant container has a liquid return passage into which the condensed liquid liquefied by the radiator flows, and the radiator includes the vapor outflow passage and the liquid. A boiling cooling device comprising: a lower tank that communicates with a return passage; and a heat exchange unit that exchanges heat between the refrigerant vapor and an external fluid is provided above the lower tank. 3. A boiling cooling device according to claim 1, wherein the boiling cooling device is mounted on an automobile and used.