JP2000065456A - Ebullient cooler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress lowering of heat radiation performance even upon inclination of an ebullient cooler by forming a circulation flow of refrigerant between a refrigerant tank and a radiator. SOLUTION: A vapor tube for supplying refrigerant vapor from a refrigerant tank 3 to a radiator 4 comprises a first vapor tube 11A having one end being coupled with one side face of the refrigerant tank 3, and a second vapor tube 11B having one end being coupled with the other side face of the refrigerant tank 3. A tube for returning condensed liquid from the radiator 4 to the refrigerant tank 3 comprises a first liquid return tube 12A having one end being coupled with one side face of the refrigerant tank 3, and a second liquid return tube 12B having one end being coupled with the other side face of the refrigerant tank 3. Since the second vapor tube 11B is opened above the refrigerant liquid level even if the first vapor tube 11A is opened below the refrigerant liquid level, refrigerant vapor can be fed through the second vapor tube 11B to the radiator 4, liquefied by the radiator 4 and returned back to the refrigerant tank 3 through the liquid return tube 12.

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 heat transport by repeated boiling and condensation of a refrigerant.

[0002]

2. Description of the Related Art As a prior art, Japanese Patent Laid-Open Publication No.
There is a boiling cooling device disclosed in Japanese Patent Publication No. 57-57. As shown in FIG. 11, this boiling cooling device has a vapor pipe 120 and a liquid return pipe 130 connecting the refrigerant tank 100 and the radiator 110, and the refrigerant pipe boiled in the refrigerant tank 100 by the vapor pipe 120. The condensed liquid liquefied in the radiator 110 can be returned to the refrigerant tank 100 by sending the liquid to the radiator 110 and the liquid return pipe 130.

[0003]

However, when the above-described boiling cooling device is mounted on an electric vehicle or the like, if the device is tilted due to the tilt of the vehicle, the following problem occurs. The steam pipe 120 for sending the refrigerant vapor to the radiator 110 is provided in the refrigerant tank 100.
, The condensed liquid is opened above the liquid level of the refrigerant tank 1.
The liquid return pipe 130 returning to 00 is opened below the liquid surface of the refrigerant with respect to the refrigerant tank 100. For this reason, as shown in FIG. 12, when the boiling cooling device is inclined and the opening of the steam pipe 120 becomes lower than the coolant level, the coolant vapor flows into the coolant tank 10.
0, it becomes difficult to flow out, and refrigerant vapor accumulates above the liquid level in the refrigerant tank 100. As a result, the refrigerant cannot satisfactorily circulate between the refrigerant tank 100 and the radiator 110, and the heat radiation performance is reduced. The present invention has been made on the basis of the above circumstances, and its purpose is to form a circulating flow of refrigerant between a refrigerant tank and a radiator to reduce the heat radiation performance even when the boiling cooling device is inclined. It is to control.

[0004]

According to a first aspect of the present invention, a steam pipe for sending refrigerant vapor boiled in a refrigerant tank to a radiator includes a first vapor pipe connected to left and right sides of the refrigerant tank and a second vapor pipe. A liquid return pipe that has a vapor pipe and both vapor pipes open above the refrigerant liquid level with respect to the refrigerant tank and returns condensed liquid liquefied by the radiator to the refrigerant tank is connected to both left and right sides of the refrigerant tank. A first liquid return pipe and a second liquid return pipe, both of which are open to the refrigerant tank below the opening of the vapor pipe. According to this configuration, even if the boiling cooling device is inclined to some extent, the openings of both steam pipes do not both come below the refrigerant liquid level,
At least one of the steam pipes always opens above the coolant level. Thereby, the refrigerant vapor boiling in the refrigerant tank is sent out to the radiator through one of the vapor pipes opening above the refrigerant liquid level, and the condensate liquefied by the radiator is returned to the liquid return pipe. Through to the coolant tank.

(Means of claim 2) The first liquid return pipe and the second liquid return pipe
Are both opened below the refrigerant liquid level in the refrigerant tank. In this case, even if the boiling cooling device is inclined to some extent, one of the liquid return pipes is always opened below the refrigerant liquid level, so that the condensed liquid can be recirculated by at least the liquid return pipe located below, Interference between the refrigerant vapor and the condensate can be prevented. As a result, the condensed liquid liquefied by the radiator can reliably return to the refrigerant tank through the liquid return pipe opened below the liquid surface of the refrigerant.

A vapor pipe for sending refrigerant vapor boiling in the refrigerant tank to the radiator is opened substantially at the center of the upper surface of the refrigerant tank with respect to the refrigerant tank, and the condensate liquid liquefied by the radiator is provided. The liquid return pipe returning to the refrigerant tank has a first liquid return pipe and a second liquid return pipe connected to the left and right sides of the refrigerant tank, and both of the liquid return pipes have openings of the vapor pipe with respect to the refrigerant tank. It opens below the part. According to this configuration, even if the boiling cooling device is inclined to some extent, the refrigerant liquid level in the refrigerant tank does not come above the opening of the vapor pipe, and the vapor pipe always opens above the refrigerant liquid level. I have. Thereby, the refrigerant vapor boiling in the refrigerant tank is sent to the radiator through the vapor pipe, and the condensed liquid liquefied by the radiator can return to the refrigerant tank through the liquid return pipe.

(Means of Claim 4) The first liquid return pipe and the second liquid return pipe
Are both opened below the refrigerant liquid level in the refrigerant tank. In this case, even if the boiling cooling device is inclined to some extent, since one of the liquid return pipes is always opened below the refrigerant liquid level, the refrigerant vapor boiling in the refrigerant tank flows into the liquid return pipe. Therefore, interference between the refrigerant vapor and the condensate can be prevented. As a result, the condensed liquid liquefied by the radiator can reliably return to the refrigerant tank through the liquid return pipe opened below the liquid surface of the refrigerant.

[0008] According to a fifth aspect of the present invention, a steam pipe for sending the refrigerant vapor boiled in the refrigerant tank to the radiator has a first steam pipe and a second steam pipe connected to the left and right sides of the refrigerant tank. The liquid return pipe for returning the condensed liquid liquefied by the radiator to the refrigerant tank is opened substantially at the center of the lower surface of the refrigerant tank with respect to the refrigerant tank. According to this configuration, even if the boiling cooling device is inclined to some extent, the openings of both the steam pipes do not come below the coolant level, and at least one of the steam pipes is always above the coolant level. Since it is open, the refrigerant vapor boiling in the refrigerant tank is sent out to the radiator through one of the vapor pipes opened above the liquid surface of the refrigerant. Further, since the liquid return pipe is opened substantially at the center of the lower surface of the refrigerant tank, even if the boiling cooling device is inclined to some extent, the refrigerant liquid level in the refrigerant tank does not come below the opening of the liquid return pipe. Instead, the liquid return pipe always opens below the refrigerant liquid level. In this case, since the condensed liquid can be returned to the refrigerant tank from the liquid return pipe, interference between the refrigerant vapor and the condensed liquid can be prevented, and the condensed liquid liquefied by the radiator surely returns to the refrigerant tank through the liquid return pipe. be able to.

The steam pipe for sending the refrigerant vapor boiled in the refrigerant tank to the radiator is opened substantially at the center of the upper surface of the refrigerant tank with respect to the refrigerant tank, and the condensed liquid liquefied by the radiator is provided. The liquid return pipe returning to the refrigerant tank is opened substantially at the center of the lower surface of the refrigerant tank with respect to the refrigerant tank. According to this configuration, even if the boiling cooling device is inclined to some extent, the refrigerant liquid level in the refrigerant tank does not come above the opening of the vapor pipe, and the refrigerant liquid level is below the opening of the liquid return pipe. I won't come. Therefore, the vapor pipe always opens above the coolant level, and the liquid return pipe always opens below the coolant level. Thereby, the refrigerant vapor boiling in the refrigerant tank is sent out to the radiator through the vapor pipe, and the condensed liquid liquefied by the radiator can surely return to the refrigerant tank through the liquid return pipe.

[0010]

Next, an embodiment of the present invention will be described with reference to the drawings. (First Embodiment) FIG. 1 is an overall view of a boiling cooling device 1.
The boiling cooling device 1 cools the heating element 2 by utilizing the boiling and condensing action of the refrigerant, and includes a refrigerant tank 3 for storing a liquid refrigerant therein, a radiator 4 provided above the refrigerant tank 3, and a refrigerant. A connecting pipe (described later) for connecting the tank 3 and the radiator 4 is provided. The heating element 2 is, for example, an IGBT module that constitutes an inverter circuit of an electric vehicle, and is fixed in close contact with the center of the lower surface of the refrigerant tank 3.

The refrigerant tank 3 is a hollow container having a substantially rectangular parallelepiped made of a metal material having excellent thermal conductivity such as aluminum.
A predetermined amount of refrigerant (for example, an amount of the refrigerant liquid level reaching about 約 of the height in the refrigerant tank 3) is sealed therein. Refrigerant tank 3
Is provided with a refrigerant flow control plate 5 for preventing interference between the refrigerant vapor boiling due to the heat of the heating element 2 and the condensate returning from the radiator 4 to the refrigerant tank 3. As shown in FIG. 1, the refrigerant flow control plate 5 has a boiling region in the refrigerant tank 3 (a region where the refrigerant is actively boiled by receiving heat from the heating element 2).
, The inner end is located at substantially the same height as the refrigerant liquid level, and the outer end is located slightly above the refrigerant liquid level.

The radiator 4 includes a core 6, an upper tank 7, and a lower tank 8. The core portion 6 has a plurality of flat tubes 9 and radiation fins 10 arranged alternately, and the flat tubes 9 are arranged vertically in correspondence with horizontal air blowing. The flat tube 9 is used by cutting a flat tube made of, for example, aluminum into a predetermined length. The radiating fins 10 are formed by alternately bending thin metal plates (for example, aluminum plates) having excellent thermal conductivity into a wavy shape, and are joined to the outer wall surface of each flat tube 9 by brazing or the like. The upper tank 7 is disposed above the core portion 6, is connected to the upper end of each flat tube 9, and communicates with each flat tube 9 in the upper tank 7. Lower tank 8
Is disposed below the core 6 and connected to the lower end of each flat tube 9, and communicates with each flat tube 9 in the lower tank 8.

The connecting pipe has two steam pipes 11 (11A, 11B) for sending the refrigerant vapor boiling in the refrigerant tank 3 to the radiator 4.
And two liquid return pipes 12 (12A, 12B) for returning the condensed liquid liquefied by the radiator 4 to the refrigerant tank 3. Steam pipe 11
Has a first steam pipe 11A having one end connected to one side of the refrigerant tank 3 and the other end connected to one side of the upper tank 7 of the radiator 4, and one end connected to the other side of the refrigerant tank 3. Connected
A second steam pipe 11B having the other end connected to the other side of the upper tank 7 of the radiator 4;
Both are connected to the refrigerant tank 3 above the outer end of the refrigerant flow control plate 5. One end of the liquid return pipe 12 has the refrigerant tank 3.
A first liquid return pipe 12A having one end connected to one side of the lower tank 8 of the radiator 4 and one end connected to the other side of the refrigerant tank 3; Second liquid return pipe 12 connected to the other side of lower tank 8 of radiator 4
B, and both the liquid return pipes 12A and 12B
Is connected below the outer end of the refrigerant flow control plate 5. In order to prevent the refrigerant vapor boiling in the refrigerant tank 3 from flowing into the liquid return pipe 12, the liquid return pipe 12 may be connected below the liquid surface of the refrigerant. Since the refrigerant flow control plate 5 is disposed at the lower side, it is not always necessary to connect the refrigerant flow control plate 5 below the liquid surface of the refrigerant.

Next, the operation and effect of this embodiment will be described. a) The case where the boiling cooling device 1 is not inclined (the state shown in FIG. 1). The heat generated from the heating element 2 is transmitted to the liquid refrigerant stored in the refrigerant tank 3 through the wall surface of the refrigerant tank 3, and the liquid refrigerant boils. The boiling refrigerant vapor flows into the upper tank 7 of the radiator 4 through the two steam pipes 11 and is distributed from the upper tank 7 to the flat tubes 9. The refrigerant vapor flowing through the flat tube 9 is cooled by heat exchange with the outside air, releases latent heat, and condenses on the inner wall surface of the flat tube 9. The latent heat released when the refrigerant vapor condenses is transmitted from the wall surface of the flat tube 9 to the radiation fins 10, and is released to the outside air through the radiation fins 10. On the other hand, the condensed liquid condensed in the flat tube 9 to form droplets flows down into the lower tank 8 along the inner wall surface of the flat tube 9, passes through the two liquid return pipes 12 from the lower tank 8, Reflux to tank 3.

B) When the cooling device 1 is inclined (FIG. 2)
State). As shown in FIG. 2, even if the boiling cooling device 1 is inclined and the opening of one of the steam pipes 11 (for example, the first steam pipe 11A) comes below the coolant level, the second steam pipe 11B is closed. The opening is open above the coolant level. Accordingly, the refrigerant vapor boiling in the refrigerant tank 3 is sent out to the radiator 4 through the second vapor pipe 11B, condensed and liquefied by the radiator 4, and then passed through the two liquid return pipes 12 to form the refrigerant tank. Reflux to 3. Since a predetermined amount of the refrigerant is hardly formed between the refrigerant liquid surface and the inner end of the refrigerant flow control plate 5 due to the inclination of the boiling cooling device 1, a predetermined amount of the refrigerant is sealed.
The refrigerant vapor does not flow into B, and interference between the refrigerant vapor and the condensate can be prevented. As a result, the condensed liquid liquefied by the radiator 4 can reliably return to the refrigerant tank 3 through the first liquid return pipe 12A. As described above, in the boiling cooling device 1 of the present embodiment, since the steam pipe 11 and the liquid return pipe 12 are connected to the left and right side surfaces of the refrigerant tank 3, respectively, even if the boiling cooling device 1 is inclined to some extent, Refrigerant can be circulated between the tank 3 and the radiator 4, and desired heat radiation performance can be secured.

(Second Embodiment) FIG. 3 is an overall view of a boiling cooling device 1. As shown in FIG. 3, the evaporative cooling device 1 of the present embodiment includes two steam pipes 11 (11A,
11B) are connected to both the left and right sides of the upper surface of the refrigerant tank 3,
The two liquid return pipes 12 (12A, 12B) are both connected to the left and right sides of the lower surface of the refrigerant tank 3. In this case, the two liquid return pipes 12 open below the refrigerant liquid level,
The refrigerant vapor does not flow into the liquid return pipe 12, and the refrigerant flow control plate 5 described in the first embodiment can be eliminated. Further, as shown in FIG. 4, even when the boiling cooling device 1 is inclined, the second steam pipe 11B always opens above the coolant level, and the first liquid return pipe 12A always drops below the coolant level. It is open to. Thus, as in the first embodiment, the refrigerant can be circulated between the refrigerant tank 3 and the radiator 4 even when the boiling cooling device 1 is inclined to some extent, and a desired heat radiation performance can be secured. .

(Third Embodiment) FIG. 5 is an overall view of a boiling cooling device 1. This embodiment shows an example in which the number of the steam pipes 11 connected to the refrigerant tank 3 is one, and the steam pipe 11 is connected to a substantially central portion of the upper surface of the refrigerant tank 3.
The first liquid return pipe 12A and the second liquid return pipe 12B can be connected to the refrigerant tank 3 and the radiator 4 in the same manner as in the first embodiment or the second embodiment. In this case, even if the evaporative cooling device 1 is inclined to some extent as shown in FIG. 6, the refrigerant liquid level in the refrigerant tank 3 does not rise above the opening of the vapor pipe 11, and the vapor pipe 11 It opens above the surface. Thereby, the refrigerant vapor boiling in the refrigerant tank 3 is sent out to the radiator 4 through the vapor pipe 11, and the condensed liquid liquefied in the radiator 4 can return to the refrigerant tank 3 through the liquid return pipe 12. Thus, desired heat radiation performance can be secured.

(Fourth Embodiment) FIG. 7 is an overall view of a boiling cooling device 1. This embodiment shows an example in which the number of the liquid return pipes 12 connected to the refrigerant tank 3 is one, and the liquid return pipe 12 is connected to a substantially central portion of the lower surface of the refrigerant tank 3. The first steam pipe 11A and the second steam pipe 11B can be connected to the refrigerant tank 3 and the radiator 4 in the same manner as in the first embodiment or the second embodiment. In this case, even if the boiling cooling device 1 is inclined to some extent as shown in FIG. 8, the refrigerant liquid level in the refrigerant tank 3 does not fall below the opening of the liquid return pipe 12, and the liquid return pipe 12 is always It opens below the coolant level. As a result, the refrigerant vapor boiling in the refrigerant tank 3 does not flow into the liquid return pipe 12 and interference between the refrigerant vapor and the condensate can be prevented. Thus, it is possible to reliably return to the refrigerant tank 3 through the passage, and a desired heat radiation performance can be secured.

(Fifth Embodiment) FIG. 9 is an overall view of a boiling cooling device 1. This embodiment shows an example in which the number of the vapor pipe 11 and the liquid return pipe 12 connected to the refrigerant tank 3 is one, and the vapor pipe 11 is connected to a substantially central portion of the upper surface of the refrigerant tank 3. The liquid return pipe 12 is connected to a substantially central portion of the lower surface of the refrigerant tank 3. In this case, as shown in FIG.
Is inclined to some extent, the refrigerant liquid level in the refrigerant tank 3 does not come above the opening of the vapor pipe 11 and the refrigerant liquid level does not come below the opening of the liquid return pipe 12. Therefore, since the vapor pipe 11 always opens above the refrigerant liquid level and the liquid return pipe 12 always opens below the refrigerant liquid level, the refrigerant vapor boiling in the refrigerant tank 3 passes through the vapor pipe 11. The condensed liquid sent out to the radiator 4 and liquefied by the radiator 4 does not interfere with the refrigerant vapor in the liquid return pipe 12 without being condensed with the refrigerant vapor.
And the desired heat dissipation performance can be secured.

(Other Embodiments) Steam Pipe 11 and Liquid Return Pipe 1
2 does not need to be one or two, and three or more may be used. It is preferable that the vapor pipe 11 through which the refrigerant vapor flows has a larger passage cross-sectional area (that is, a larger pipe diameter) than the liquid return pipe 12 through which the condensate flows. Although the coolant tank 3 uses a hollow container having a substantially rectangular parallelepiped shape, the present invention is not limited to this. For example, a flat coolant tank 3 having a small width may be used.

[Brief description of the drawings]

FIG. 1 is an overall view of a boiling cooling device (first embodiment).

FIG. 2 is a drawing of a boiling cooling device for explaining an operation at the time of tilting (first embodiment).

FIG. 3 is an overall view of a boiling cooling device (second embodiment).

FIG. 4 is a drawing of a boiling cooling device for explaining an operation at the time of tilt (second embodiment).

FIG. 5 is an overall view of a boiling cooling device (third embodiment).

FIG. 6 is a drawing of a boiling cooling device for explaining an operation at the time of inclination (third embodiment).

FIG. 7 is an overall view of a boiling cooling device (fourth embodiment).

FIG. 8 is a drawing of a boiling cooling device for explaining an operation at the time of tilting (fourth embodiment).

FIG. 9 is an overall view of a boiling cooling device (fifth embodiment).

FIG. 10 is a drawing of a boiling cooling device for explaining the operation at the time of tilting (fifth embodiment).

FIG. 11 is an overall view of a boiling cooling device (prior art).

FIG. 12 is an overall view of a boiling cooling device showing a tilted state (prior art).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Boiling cooling device 2 Heating element 3 Refrigerant tank 4 Radiator 11 Steam pipe 11A First steam pipe 11B Second steam pipe 12 Liquid return pipe 12A First liquid return pipe 12B Second liquid return pipe

Claims (6)

[Claims] 1. A boiling cooling device for cooling a heating element by heat transport by repeated boiling and condensation of a refrigerant, comprising: a refrigerant tank for storing therein a refrigerant vaporized by heat generated by the heating element; A radiator that condenses and liquefies the refrigerant vapor that has boiled by receiving heat from the heating element by heat exchange with an external fluid; a steam pipe that sends the refrigerant vapor that has boiled in the refrigerant tank to the radiator; A liquid return pipe for returning the liquefied condensate to the refrigerant tank, wherein the vapor pipe is connected to left and right sides of the refrigerant tank.
And a second steam pipe, both of which open above the coolant level with respect to the refrigerant tank, and wherein the liquid return pipe is connected to both left and right sides of the refrigerant tank. A boiling cooling device comprising: a first liquid return pipe and a second liquid return pipe, both of which are open below the opening of the vapor pipe with respect to the refrigerant tank. 2. The boiling according to claim 1, wherein both the first liquid return pipe and the second liquid return pipe are opened below a refrigerant liquid level in the refrigerant tank. Cooling system. 3. A boiling cooling device for cooling a heating element by heat transport by repetition of boiling and condensation of a refrigerant, comprising: a refrigerant tank for storing therein a refrigerant vaporized by heat generated by the heating element; A radiator that condenses and liquefies the refrigerant vapor that has boiled by receiving heat from the heating element by heat exchange with an external fluid; a steam pipe that sends the refrigerant vapor that has boiled in the refrigerant tank to the radiator; A liquid return pipe for returning the liquefied condensed liquid to the refrigerant tank, wherein the vapor pipe is opened substantially at the center of the upper surface of the refrigerant tank with respect to the refrigerant tank, and the liquid return pipe is provided in the refrigerant tank. It has a first liquid return pipe and a second liquid return pipe connected to both left and right sides, and both liquid return pipes are opened below the opening of the vapor pipe with respect to the refrigerant tank. Characterized boiling cooling device. 4. The boiling according to claim 3, wherein both the first liquid return pipe and the second liquid return pipe are opened below a refrigerant liquid level in the refrigerant tank. Cooling system. 5. A boiling cooling device for cooling a heating element by heat transport by repetition of boiling and condensation of a refrigerant, comprising: a refrigerant tank for storing therein a refrigerant vaporized by heat generated by the heating element; A radiator that condenses and liquefies the refrigerant vapor boiling due to the heat of the heating element by heat exchange with an external fluid, a steam pipe that sends the refrigerant vapor boiling in the refrigerant tank to the radiator, A liquid return pipe for returning the liquefied condensate to the refrigerant tank, wherein the vapor pipe is connected to left and right sides of the refrigerant tank.
And a second steam pipe, both of which are open above the coolant level with respect to the refrigerant tank, and wherein the liquid return pipe has a lower surface of the refrigerant tank with respect to the refrigerant tank. An ebullient cooling device characterized by being open at substantially the center. 6. A boiling cooling device for cooling a heating element by heat transport by repeated boiling and condensation of a refrigerant, comprising: a refrigerant tank for storing therein a refrigerant that is vaporized by heat generated by the heating element; A radiator that condenses and liquefies the refrigerant vapor boiling due to the heat of the heating element by heat exchange with an external fluid, a steam pipe that sends the refrigerant vapor boiling in the refrigerant tank to the radiator, A liquid return pipe for returning the liquefied condensed liquid to the refrigerant tank, wherein the vapor pipe is opened substantially at the center of the upper surface of the refrigerant tank with respect to the refrigerant tank, and the liquid return pipe is provided in the refrigerant tank. On the other hand, an ebullient cooling device characterized in that it is open at substantially the center of the lower surface of the refrigerant tank.