JPH1098142A - Boiling cooler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily change the capacity of a radiator, if the total quantity of heat generation with increase of the no. of heat generating components by stacking identical hollow radiation pipes on coupling members connected to a coolant tank. SOLUTION: When the radiation quantity increases, a coolant tank blows up a large quantity of bubbles to penetrate a gas- and liq.-phase coolants into an inlet return chamber 461 which has a small-aperture opening 411 to block the liq. phase of the mixed coolant from penetrating a radiation passage 42, the blocked coolant being returned to the liq. coolant tank through a return passage 421, resulting in a reduced amt. of the liq. coolant, whereas the mixed coolant penetrates into the radiation passage 42 via the opening 411. This allows the condensation heat transfer area of the radiation passage 42 to be increased.

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 that absorbs heat from a high-temperature medium and cools the high-temperature medium, and is used for cooling a heating element such as a semiconductor element or an electric device. There is a cooling device and the like.

[0002]

2. Description of the Related Art Conventionally, a boiling cooling apparatus for cooling heat generated by a heating element as a high-temperature medium has been known. Among them, flooding of a vapor refrigerant which rises by being vaporized in a refrigerant tank and a liquefied refrigerant which is cooled by a radiator and returns to a refrigerant tank as in a boiling cooling device disclosed in Japanese Patent Application Laid-Open No. 56-147457. There is known a boiling cooling device that prevents heat collision with each other and efficiently performs heat exchange.

[0003] That is, a boiling cooling device disclosed in Japanese Patent Application Laid-Open No. 56-147457 is arranged such that a refrigerant tank for containing a refrigerant that evaporates and evaporates due to heat generated by a heating element, and is connected to the refrigerant tank above the refrigerant tank. An inlet-side passage having substantially the same diameter, a radiator including a plurality of heat-dissipating passages communicating with the inlet-side passage, and an outlet-side passage for returning the refrigerant condensed and liquefied by the radiator to the refrigerant tank. ing.

[0004] In such a boiling cooling device, normally (when the heat release amount is small), bubbles of the refrigerant are blown up and proceed in the inflow passage in the gas phase, and heat is transmitted by the gas phase refrigerant. That is, the gaseous refrigerant is in direct contact with the inner wall of the heat radiating passage, and conducts heat by condensation heat transfer that directly transfers heat to the inner wall.

[0005]

However, Japanese Unexamined Patent Publication No.
In the evaporative cooling device as disclosed in JP-A-147457, a large amount of heat is released, so that many bubbles are blown up, and a part of the gas flows in the inflow passage in a liquid phase. Will transmit heat. At the portion where the liquid phase has entered the heat dissipation passage, the heat transfer changes from condensation heat transfer to forced convection heat transfer (transfer to the heat dissipation passage via the liquid-phase refrigerant attached to the inner wall of the heat dissipation passage). The heat conductivity of forced convection heat transfer is 1/1
It is 10 to 1/20.

In the boiling cooling device disclosed in Japanese Patent Application Laid-Open No. 56-147457, since the inflow-side passage arranged in communication with the refrigerant tank has substantially the same diameter, the liquid phase entering the heat-dissipating passage can be used. There is a problem in that the amount of the refrigerant increases, and the heat radiation characteristics of the entire device are greatly reduced. Also, JP-A-56-14
In the boiling cooling device disclosed in Japanese Patent No. 7457, since the inflow-side passages arranged in communication with the refrigerant tank have substantially the same diameter, the flow passage resistance in the inflow-side passages is small. For this reason,
The gaseous phase refrigerant that has reached the inflow side passage ascending, more gaseous refrigerant stays at the end of the inflow side passage away from the entrance,
The temperature near the end becomes higher. Even if a plurality of heat radiating passages are provided, the temperature of the heat radiating passage far from the end portion becomes low, so that heat cannot be effectively radiated. Therefore, there is a problem that the heat radiation performance is poor for the radiator.

Accordingly, an object of the present invention is to provide a boiling cooling device which prevents deterioration of heat radiation performance with a novel configuration. Another object of the present invention is to provide a boiling cooling device that reduces the amount of liquid-phase refrigerant (liquid refrigerant) that enters the heat radiation passage. Still another object of the present invention is to provide a boil cooling device that has a radiator including a plurality of heat radiating passages and that prevents the heat radiating amount of each heat radiating passage from being biased.

Another object of the present invention is to provide a boil cooling device which has a radiator including a plurality of heat radiating passages and which prevents the amount of refrigerant flowing into each refrigerant passage from being biased.

[0009]

The present invention has the following features to attain the object mentioned above. According to the first aspect of the invention, the radiator (4) communicates with the refrigerant tank (3), and the large-diameter portion (r1) and the small-diameter portion (r2) are alternately formed in the moving direction of the mixed refrigerant. Inlet passages (44, 46)
1) Outflow-side passages (45, 47) communicating with the refrigerant tank (3)
1) and a plurality of heat radiation passages (421, 42) for communicating the inflow side passage and the outflow side passage.

When the amount of heat radiation increases, many bubbles are blown up from the refrigerant tank, and refrigerant in both gas and liquid phases enters the inflow-side passages (44, 461). The inflow-side passage suppresses the liquid refrigerant in the mixed refrigerant from entering the adjacent heat-dissipating passage (42) by the small-diameter portion (r2) formed in the moving direction of the mixed refrigerant. That is, the small diameter portion (r
According to 2), the liquid refrigerant in the mixed refrigerant is blocked. The blocked liquid refrigerant is returned to the refrigerant tank.
Therefore, the amount of the mixed refrigerant that has passed through the small-diameter portion (r2) and enters the heat radiation passage has a reduced amount of the liquid refrigerant.
Thereby, the area for conducting the condensation heat in the heat radiation passage can be increased.

According to the third aspect of the present invention, the refrigerant tank (3) has therein a vapor passage (9) in which gaseous refrigerant and liquid refrigerant vaporized by heat of the high-temperature medium rise, and is cooled by the radiator. Because of the condensed liquid passage (10) through which the cooled refrigerant flows, it is possible to prevent flooding (a phenomenon in which the refrigerant heated to a high temperature by the heat of the high-temperature medium collides with the cooled refrigerant) in the refrigerant tank. it can.

According to the fourth aspect of the present invention, the radiator (4) is connected to the refrigerant tank side outlet (3) in the refrigerant tank (3).
5) and is smaller in diameter (r) than its own inner diameter (r1).
2) The inlet-side return chamber (461) having the small-diameter opening (411) and closing the liquid refrigerant of the mixed refrigerant with the small-diameter opening, and being connected to and blocked by the outlet-side return chamber. A liquid refrigerant return part (341) having a return passage (421) for returning the liquid refrigerant to the refrigerant tank.

When the amount of heat radiation increases, many air bubbles are blown up from the refrigerant tank, and refrigerant in both gas and liquid phases enters the inflow-side return chamber (461). The inflow side return chamber (461) suppresses the liquid refrigerant of the mixed refrigerant from entering the heat radiation passage by the small-diameter opening (411). That is, the liquid refrigerant of the mixed refrigerant is blocked by the small-diameter opening (411). The blocked liquid refrigerant is returned to the refrigerant tank through the return passage (421). Therefore, the amount of the mixed refrigerant that has passed through the small-diameter opening (411) and enters the heat radiation passage is reduced. Thereby, the area for conducting the condensation heat in the heat radiation passage can be increased.

According to the fifth aspect of the present invention, the inflow side return chamber of the liquid refrigerant return section (341) 341 has a bottom surface, and the lowermost portion of the small-diameter opening portion at an opening position is a predetermined height higher than the bottom surface. Since it is set at the upper part, of the mixed refrigerant that has passed through the refrigerant tank side outlet (35), it is possible to efficiently block the liquid refrigerant that is blown up from the refrigerant tank. According to the sixth aspect of the present invention, since the small-diameter opening is a substantially elliptical or substantially rectangular hole, the liquid refrigerant in the mixed refrigerant that has passed through the refrigerant tank side outlet (35) is efficiently blocked. Can be stopped. Thereby, the effective area of the radiator can be increased, and the heat radiation performance can be improved.

According to the invention described in claim 7, the liquid refrigerant return portion has an outflow side return chamber connected to the inflow port on the refrigerant tank side, and the return passage and the heat radiation passage are provided via the outflow side return chamber. Since it is communicated with the refrigerant tank, the connection between the return passage and the refrigerant tank and the connection between the heat radiation passage and the refrigerant tank can be shared, and the processing of the refrigerant tank can be facilitated. According to the invention described in claim 8, the refrigerant tank (3) has therein a vapor passage (9) in which the gas refrigerant and the liquid refrigerant vaporized by the heat of the high-temperature medium rise, and the refrigerant cooled by the radiator. Condensate passage through which water flows down (10)
Therefore, flooding in the refrigerant tank (a phenomenon in which a gaseous refrigerant that rises in temperature due to the heat of a high-temperature medium and a liquid refrigerant that is cooled and flows down collide with each other) can be prevented.

According to the ninth aspect of the invention, the heat radiation passage (42) has a bottom surface inside, and the bottom surface is inclined downward from the refrigerant tank side outlet side to the refrigerant tank side inlet side. Therefore, the condensed liquid flowing through the heat radiation passage easily flows toward the refrigerant tank. For this reason, the amount of the condensed liquid refrigerant that accumulates on the bottom surface of the heat radiation passage is reduced, the area for condensing heat transfer can be increased, and the gas refrigerant can be efficiently condensed.

According to the tenth aspect of the invention, the radiator is located on the inflow side of the mixed refrigerant, and the first large-diameter portion (461), the small-diameter portion (411) and the first large-diameter portion (411) are arranged in the moving direction of the mixed refrigerant. The second large-diameter portion (44) communicates with the inflow-side passage formed in this order, the first large-diameter portion, and the return passage (through which the liquid refrigerant blocked by the small-diameter portion of the mixed refrigerant flows). 421), a heat-dissipating passage (42) through which the gaseous refrigerant that is communicated with the second large-diameter portion and that has passed through the small-diameter portion of the mixed refrigerant is introduced to condense and liquefy the gaseous refrigerant, and the return passage and the heat-dissipation passage An outlet-side passage is provided for returning the liquid refrigerant and the condensed and liquefied refrigerant to the refrigerant tank.

When the amount of heat radiation increases, many air bubbles are blown up from the refrigerant tank, and refrigerant in both gas and liquid phases enters the first large-diameter portion (461). The first large diameter portion (46
1) The small-diameter portion (411) suppresses the liquid refrigerant of the mixed refrigerant from entering the heat radiation passage via the second large-diameter portion (44). That is, the small diameter portion (4
According to 11), the liquid refrigerant in the mixed refrigerant is blocked. The blocked liquid refrigerant is returned to the return passage (42).
It is returned to the refrigerant tank through 1). Therefore, the mixed refrigerant that passes through the small-diameter portion (411) and enters the heat radiation passage is:
The amount of the liquid refrigerant is reduced. Thereby, the area for conducting the condensation heat in the heat radiation passage can be increased.

Further, by providing the small-diameter openings, it is possible to prevent the flow of the refrigerant into each of the heat radiating passages (42) from being biased, and to further effectively distribute the refrigerant to each of the heat radiating passages (42). However, these also can prevent the heat radiation performance from being lowered. According to the eleventh aspect, the first large-diameter portion has a bottom surface, and the lowermost portion of the opening position of the small-diameter portion is set at a predetermined height above the bottom surface. Of the mixed refrigerant introduced into the caliber portion, the liquid refrigerant blown up from the refrigerant tank can be efficiently blocked.

According to the twelfth aspect of the present invention, since the small-diameter portion is a substantially elliptical or substantially rectangular hole, the liquid refrigerant of the mixed refrigerant introduced into the first large-diameter portion can be efficiently used. Can be blocked. Thereby, the effective area of the radiator can be increased, and the heat radiation performance can be improved. The liquid refrigerant descending due to its own weight can be efficiently blocked.

According to the thirteenth aspect of the present invention, the refrigerant tank (3) has therein a vapor passage (9) in which gaseous refrigerant and liquid refrigerant vaporized by heat of the high-temperature medium rise, and is cooled by the radiator. Since it has the condensed liquid passage (10) through which the discharged refrigerant flows, flooding in the refrigerant tank can be prevented. According to the fourteenth aspect of the present invention, when a small-diameter portion is also formed in the outflow-side passage, the refrigerant transmitted through the refrigerant passage is blocked and accumulated in the small-diameter portion, and circulates in the device. There is a possibility that the effective refrigerant amount related to heat dissipation may decrease, but since the lowermost part of the small diameter portion of the outflow side passage is set below the lowermost part of the refrigerant passage, it is blocked by the small diameter portion. The amount of refrigerant that accumulates can be reduced. For this reason, the amount of the enclosed refrigerant can be reduced, and the cost can be reduced.

According to the fifteenth aspect of the present invention, the radiator communicates with the vapor passage and has an inflow passage having a plurality of inflow communication chambers, and the outflow passage having a plurality of outflow communication chambers communicating with the condensate passage. A passage, a plurality of heat-radiating passages communicating the specific inflow-side communication chamber with the specific outflow-side communication chamber, and an inflow of the liquid refrigerant into the adjacent inflow-side communication chamber formed between the plurality of inflow-side communication chambers Mouth (41)
1, 41).

For this reason, every time the mixed refrigerant passes through the suppression port, the amount of the mixed refrigerant that enters the heat radiation passage is reduced. Thereby, the area for conducting the condensation heat in the heat radiation passage can be increased. According to the sixteenth aspect of the present invention, since the suppression port is a substantially elliptical or substantially rectangular hole, it is possible to efficiently block the liquid refrigerant of the mixed refrigerant. Thereby, the effective area of the radiator can be increased, and the heat radiation performance can be improved.

According to the seventeenth aspect, the heat radiation passage has a bottom surface inside, and the bottom surface is inclined downward from the inflow side passage side to the outflow side passage side. The flowing condensate becomes easier to flow toward the refrigerant tank.
For this reason, the amount of the condensed refrigerant accumulated on the bottom surface of the refrigerant passage is reduced, and the area for condensing heat transfer can be increased,
The gas refrigerant can be efficiently condensed.

According to the eighteenth aspect of the present invention, the radiator is formed by bonding a plurality of plate-like members having a bonding portion at the bonding portion. Since it is formed by bending and raising the plate-shaped member, a large uniform load can be applied to the bonded portion when the plate-shaped member is bonded. Thereby, the airtightness at the time of bonding can be improved, and as a result, the heat radiation performance can be improved.

According to the nineteenth aspect of the present invention, the radiator (4) reduces the amount of the liquid refrigerant flowing from the refrigerant tank (3) which adheres to the inner wall of the heat radiation passage. (461, 421, 411),
The area for condensing heat transfer in the heat dissipation passage can be increased.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described. (First Embodiment) FIG. 1 is a side view of a boiling cooling device according to a first embodiment, FIG. 2 is a sectional view taken along line BB in FIG. 1, FIG. 3 is a sectional view taken along line CC in FIG. 4 is a plan view and a side view of the molding plate, and FIG.
It is sectional drawing.

The boiling cooling device 1 of the present embodiment is a cooling device for cooling an IGBT module 2 constituting an inverter circuit of an electric vehicle or a general power control device as a high-temperature medium, for example, a refrigerant tank 3, a radiator 4, And a cooling fan 5. As shown in FIG. 1, the IGBT module 2 is fixed to an outer wall surface of the refrigerant tank 3 by tightening bolts 6. It is preferable that the IGBT module 2 is fixed between the heat radiating plate and the outer wall surface of the refrigerant tank 3 via heat conductive grease.

The refrigerant tank 3 includes a hollow extruded material 7 obtained by extrusion from, for example, an aluminum block material, and end caps 22 (22a, 22b) for closing the open ends of the upper and lower ends of the extruded material 7. Consists of The other open end of the extruded member 7 is connected to the radiator 4 as a refrigerant inlet / outlet. As shown in FIGS. 2 and 3, the extruded material 7 is made of IG.
A vapor passage 9, which is provided in a flat shape having a thinner width W with respect to a lateral width and a longitudinal width of an outer wall surface to which the BT module 2 is attached, and is partitioned by columns 30, 31, 32 extending in a vertical direction; The passage 10 and the non-operating passage 33 are formed so as to penetrate in the longitudinal direction, and the refrigerant of the vapor passage 9 is formed in a region where the radiator 4 (radiation pipe 39) is connected via the connection plate 34 (see FIG. 1). The tank side outlet 35 and the refrigerant tank side inlet 36 of the condensate passage 10 are open.

The plurality of vapor passages 9 and the condensate passage 1
0, and the non-operating passage 33 are opened at a position slightly lower than the upper end of the extruded material 7 by removing the upper end of each of the struts 30 to 32, and the opening surface of each of the steam passages 9 and The opening surfaces of the condensed liquid passage 10 are provided as a refrigerant tank side outlet 35 for the vapor refrigerant and a refrigerant tank side inlet 36 for the condensed liquid. Further, a female screw portion for screwing the bolt 6 is formed in the thick portion 7a of the extruded material 7 where the passages 9 and 10 are not formed.

However, the refrigerant tank side outlet 35 is opened above the non-operating passage 33, and the column 31 remaining between the two steam passages 9 and between the steam passage 9 and the non-operating passage 33. The upper portion of the remaining support portion 32 (portion indicated by a broken line F in FIG. 3) is deleted by additional processing such as milling to communicate with the steam passages 9. Further, screw holes 37 for screwing the mounting bolts 6 of the IGBT module 2 are formed in each of the columns 30 to 32. The non-operating passage 33 is formed in order to balance with the condensed liquid passage 10 at the time of the extrusion processing.
Not used as 0. Therefore, it is not always necessary to form the non-operation passage 33.

The end caps 22 are joined to both ends of the extruded material 7 by integral brazing. However, the end cap 22a on the upper end side closes the upper end opening surface of the extruded material 7, but the end cap 22b on the lower end side has the vapor passage 9, the condensed liquid passage 10 and the lower end surface of the extruded material 7. , And a lower communication passage 38 which communicates with the non-operation passage 33.

The radiator 4 is a so-called Dron cup type heat exchanger. As shown in FIG. 4A, a plurality of radiator tubes 39 formed by alternately stacking thin formed plates 40 having the same shape are formed. It is configured by being stacked in parallel. The radiator 4
It is connected to the refrigerant tank 3 via the connection plate 34 (see FIG. 5). As shown in FIG. 5, the connection plate 34 covers the refrigerant tank side outlet 35 and the refrigerant tank side inlet 36 formed in the extruded material 7 and is airtightly joined to the outer wall surface of the extruded material 7. And the connection plate 34 has the extruded material 7
The inflow side return chamber 461 (the large-diameter opening, the large-diameter portion, the first diameter) is communicated with the refrigerant tank side outlet 35 of the refrigerant tank 3 and has a predetermined inner diameter (r1) by the space surrounded by the outer wall surface of the first tank. Large-diameter portion), an outflow-side return chamber 471 and an inflow-side return chamber 4 communicated with the refrigerant tank-side inlet 36 and having a predetermined inner diameter (r1).
61 and the return passage 42 communicating with the outlet side return chamber 471.
Liquid refrigerant return section 341 (adhesion amount reducing means)
Is composed.

A small-diameter opening 411 (small-diameter portion, suppression port) having a smaller diameter (r2) than the inner diameter of the inflow-side return chamber 461 is provided on the side of the inflow-side return chamber 461 opposite to the refrigerant tank-side outlet 35. Are formed. The liquid refrigerant return section 341
Is communicated with each heat radiation pipe 39 through the small-diameter opening 411. The heat radiating tube 39 is composed of two forming plates 40 (see FIG. 4A) having a substantially rectangular planar shape.
The outer peripheral edge of each forming plate 40 is joined to form a hollow body. The two forming plates 40 are formed in the same shape by press-forming a metal material (for example, aluminum material) having good thermal conductivity, and have small-diameter openings 41 (small-diameter portions, suppression ports) at both ends. It is open. FIG.
(B) is a plan view of the forming plate 40. FIG. 4 (b)
As shown in (1), the small-diameter opening 41 is formed by a substantially elliptical or substantially rectangular hole. Here, the small-diameter opening 41 has a diameter r2, and a large-diameter opening (large-diameter portion) having a diameter r1 (r1> r2) is formed around the small-diameter opening 41.

The heat radiating pipe 39 has a flat heat radiating passage 42 in its entire central portion, and its ends have a large diameter inlet-side communication chamber 44 (space connected to the refrigerant tank side outlet 35 side). And an outflow side communication chamber 45 (a space connected to the refrigerant tank side inflow port 36 side). The radiator 4
When a plurality of heat radiation tubes 39 are stacked, a plurality of heat radiation passages 42 and an inflow side passage and an outflow side passage connected to the ends of the heat radiation passages 42 are provided. Here, the inflow-side passage is configured by stacking a plurality of inflow-side communication chambers 44, and the outflow-side passage is configured by stacking a plurality of outflow-side communication chambers 45. And
The inflow-side passage and the outflow-side passage are formed between the inflow-side communication chambers 44 and the outflow-side communication chambers 45 to which the heat radiation passages 42 communicate.
Each has a small aperture 41 between each other. This allows
The inflow-side passage and the outflow-side passage have a plurality of large-diameter portions (r1) and small-diameter portions (r2) alternately arranged therein. The small-diameter opening 41 formed with the punched hole is
It also serves as a suppression port that suppresses the amount of liquid refrigerant that enters between adjacent inflow-side communication chambers 44.

In the present embodiment, the radiator tubes 39 are stacked substantially at right angles to the coolant tank 3 and substantially horizontally to the coolant level. However, the liquid refrigerant accumulated in the heat radiating pipe 39 can be efficiently returned to the refrigerant tank 3 by inclining the liquid refrigerant in the upward direction as the distance from the refrigerant tank 3 increases. As shown in FIG.
Radiating fins 16 are interposed between them. However, the small-diameter opening 41 is not provided on the outermost forming plate 40 of the outermost heat radiation tube 39. Alternatively, even when a forming plate 40 having a small-diameter opening 41 is used, the communication port 41 may be closed by an end plate (not shown) or the like from the outside of the forming plate 40.

The small-diameter opening 41 of the radiator tube 39 and the small-diameter opening 411 of the liquid refrigerant return portion 341 communicate with each other, and the inflow-side passage and the inflow-side return chamber 461 formed of the plurality of inflow-side communication chambers 44 are provided. Is communicated. Further, an outflow-side passage including a plurality of outflow-side communication chambers 45 and an outflow-side return chamber 471 are provided.
Are also communicated at the same time. Thus, the radiator 4 is configured.

In FIG. 1, the cooling fan 5 is, for example, an axial fan, which is disposed on the upper surface of the radiator 4 and blows air to the radiator 4 in a vertical direction. Note that the cooling fan 5 may be a suction type located downstream of the radiator 4 in the blowing direction or a push-type cooling fan located upstream of the radiator 4 in the blowing direction. Further, the cooling fan 5 may be a cross-flow fan, and the arrangement position may be a front surface or a rear surface of the radiator 4.

Next, the operation of the first embodiment will be described.
In FIG. 6, the refrigerant boiled by transferring the heat generated from the IGBT module 2 rises in the vapor passage 9 as bubbles and flows into the outflow side communication chamber 461 from the refrigerant tank side outlet 35. Thereafter, in FIG. 5, the gas further flows from the outflow side communication chamber 461 to the inflow side communication chamber 44 and is distributed to the heat radiation passages 42 of the heat radiation tubes 39. The vapor refrigerant flowing through each heat radiation passage 42 is condensed on the inner wall surface of the heat radiation passage 42 and the surface of the inner fin 43 which are cooled by the blowing of the cooling fan 5 to release condensed latent heat, and is radiated as droplets. Passage 4
2 flows into the outflow side communication chamber 45 of the radiator 4 while flowing on the bottom surface of the radiator 2. The condensed liquid flows into the condensed liquid passage 10 from the refrigerant tank side inlet 36, flows down the condensed liquid passage 10, and is supplied again to the vapor passage 9 through the lower communication passage 38 in the end cap 22b shown in FIG. Is done. On the other hand, the latent heat of condensation released when the vapor refrigerant is condensed is transmitted from the wall surface of the heat radiating passage 42 to the heat radiating fins 16, and is discharged to the blast air passing between the heat radiating tubes 39.

(Effect of First Embodiment) In FIG.
When the heat release amount increases, many bubbles are blown up from the refrigerant tank, and the refrigerant in both gas and liquid phases enters the inflow side return chamber 461 (in FIG. 6, the gas refrigerant is represented by a white circle, and the liquid refrigerant is represented by a black circle). ). The inflow-side return chamber 461 prevents the liquid refrigerant of the mixed refrigerant from entering the heat radiation passage by the small-diameter opening 411. That is, the small-diameter opening 41
1 blocks the liquid refrigerant of the mixed refrigerant. The blocked liquid refrigerant is returned to the refrigerant tank through the return passage 421. Therefore, the mixed refrigerant that enters the heat radiation passage 42 through the small-diameter opening 411 has a reduced amount of the liquid refrigerant. Thereby, the heat radiation passage 42
The area for condensing heat transfer can be increased.

From another point of view, the inflow-side communicating portion 461 of the radiator 4 has large-diameter portions (r1) and small-diameter portions (r2) formed alternately in the moving direction of the mixed refrigerant. In addition, the small-diameter portion (r2) prevents the liquid refrigerant of the mixed refrigerant from entering the adjacent heat dissipation passage 42. Therefore, the amount of the mixed refrigerant that has passed through the small-diameter portion (r2) and enters the heat radiation passage has a reduced amount of the liquid refrigerant. Thereby, the area for conducting the condensation heat in the heat radiation passage can be increased.

In FIG. 3, when the amount of heat radiation increases, a refrigerant containing many bubbles (a refrigerant in a mixed state of a gas phase and a liquid phase) is blown up to the refrigerant tank side outlet 35 and rises. . Here, in FIG. 5, if the inside of the inflow-side passage is straight (having the same diameter), not only the gas-phase (vapor) refrigerant but also many liquid-phase refrigerants enter the heat radiation passage, and the heat radiation passage 4 at that time.
The vicinity of the inlet of No. 2 is filled with the liquid phase. In this case, heat transfer is performed not only by condensation heat transfer but also by forced convection heat transfer. In the forced convection heat transfer, the heat transfer coefficient is significantly inferior to that of the condensed heat transfer, so that the heat radiation characteristics deteriorate. However, in the present embodiment, since the small-diameter opening 411, which is a small-diameter portion, is provided in the inflow-side passage, the infiltration of the liquid-phase refrigerant into the heat radiation passage 42 can be suppressed. As a result, the heat can be transferred mainly by the condensation heat transfer in the heat dissipation passage 42, and the heat dissipation performance can be prevented from lowering. Further, by providing the small-diameter openings 41, it is possible to prevent the inflow of the refrigerant into each of the heat radiating passages 42, and furthermore, it has an effect of evenly distributing the refrigerant to each of the heat radiating passages 42,
These can also prevent a decrease in heat radiation performance.

Further, in the refrigerant in the refrigerant tank 3, when the amount of heat radiation increases, bubbles increase inside the refrigerant and the liquid level rises. At this time, the refrigerant tank side inflow port 35 is closed when the liquid level rises. Accordingly, it is possible to suppress the liquid refrigerant from entering the heat radiation passage. Further, the lowermost portion of the opening position of the small-diameter opening 411 is set above the bottom surface of the inflow-side return chamber 461 by a predetermined height ((r1−r2) / 2). This predetermined height portion is a blockage that blocks the liquid-phase refrigerant that has passed through the refrigerant tank-side outlet 35 and falls by its own weight. Accordingly, it is possible to suppress the liquid refrigerant from entering the heat radiation passage. Further, since the refrigerant tank side inflow port 35 is constituted by a substantially elliptical or substantially rectangular shape, it is possible to efficiently block the liquid-phase refrigerant descending by its own weight.

(Other effects of the first embodiment) By using the radiator 4 of the Dron cup type, the IGB
Even when the number of T modules 2 attached increases and the total heat generation increases, the capacity of the radiator 4 can be easily changed. That is, by sequentially stacking the radiator tubes 39 having the same shape, the capacity of the radiator 4 can be easily increased, so that the radiator 4 having a capacity corresponding to the total calorific value can be provided at low cost. Further, since the steam passages 9 can be communicated with the refrigerant tank side outlet 35 only by removing the upper portions of the support portions 31 and 32 of the extruded material 7, the refrigerant can be cooled at low cost without adding any special parts. Can control circulation.

In this embodiment, the radiator 4 may be inclined with respect to the refrigerant tank 3 in order to easily return the condensed liquid from the radiator 4 to the refrigerant tank 3 (condensate passage 10). good. In addition, as shown in FIG. 41, in place of the end cap 22b on the lower end side of the coolant tank 3, the lower portions of the support portions 30 to 32 provided on the extruded material 7 are deleted by additional processing such as milling, and the extrusion is performed. A flat plate 48 (end cap 22) may be joined to the lower end surface of the material 7 by brazing. This facilitates the manufacture of the lower end cap 22 (the flat plate 48).

In the present embodiment, the refrigerant tank side inlet 36 and the refrigerant tank side outlet 35 are formed with a difference in height, but they may be provided at the same height. Further, the refrigerant tank side inlet 36 and the refrigerant tank side outlet 35 may have the same shape. In the evaporative cooling device 1 of the present embodiment, the refrigerant tank 3 is configured by using an extruded material 7. For this reason, the mold cost required for the extruded material 7 can be reduced as compared with a case where the refrigerant tank 3 is formed by bonding thin members pressed together to form the flat refrigerant tank 3. Even when the number of IGBT modules 2 is increased, if the increasing number of IGBT modules 2 are arranged in multiple stages (longitudinal direction), the extruded material 7 can be cut into an appropriate length and used, so that press forming is performed. There is no need to provide a new press die as in the case of using a product, and the cost of the die can be greatly reduced.

Since the refrigerant tank 3 is formed by using the extruded material 7, the rigidity of the mounting surface of the extruded material 7 to which the IGBT module 2 is mounted can be sufficiently secured. For this reason, the contact thermal resistance between the mounting surface (the outer wall surface of the extruded material 7) and the IGBT module 2 can be reduced as compared with the case where the refrigerant tank 3 is formed of a thin member such as a press-formed product. The heat radiation performance can be improved. In addition, since the extruded material 7 is used, the thick portion 7a for forming the female screw portion can be sufficiently secured, and the shapes of the steam passage 9 and the condensate passage 10 can be set freely. This means that the coolant tank 3
This is also advantageous in improving the pressure resistance when is made flat. In other words, although it is disadvantageous in terms of pressure resistance to make the refrigerant tank 3 flat in order to reduce the amount of refrigerant used, the vapor passage 9 and the condensate passage 10 are required to ensure sufficient pressure resistance.
Can be set.

Further, the thick portion 7a forming the female screw portion
By providing a margin for the mounting area of the IGBT module 2, the same extruded material 7 can be used for various IGBT modules 2 having different mounting screw pitches. In other words, for the refrigerant tank 3 using the extruded material 7 having the same shape,
Various IGBT modules 2 with different mounting screw pitch
Can be attached. Accordingly, the refrigerant tank 3 can be standardized, so that the cost can be reduced when the IGBT modules 2 having different mounting screw pitches are used.

Further, since the inside of the refrigerant tank 3 is divided into the vapor passage 9 and the condensed liquid passage 10, the flows of the boiling refrigerant and the condensed refrigerant in the refrigerant tank 3 can be clearly separated. This prevents so-called flooding in which the boiling refrigerant and the condensing refrigerant collide with each other, so that high heat dissipation performance can be obtained. In addition, since the vapor passage 9 and the condensate passage 10 are separated from each other, the refrigerant in the condensate passage 10 is not directly heated by the heat conducted from the IGBT module 2. The temperature is lower than that. Then, the low-temperature refrigerant is sequentially supplied from the condensed liquid passage 10 to the vapor passage 9 through the communication port 17, so that the IGBT module 2 can be efficiently cooled.

(Second Embodiment) FIG. 7 is a perspective view of a boiling cooling device 1 according to a second embodiment, FIG. 8 is a partial cross-sectional view taken along the line II ′ in FIG. 7, and FIG. II 'is a partial sectional view, and FIG. 10 is a partial sectional view taken along the line III-III' in FIG. 7 to 10, the present embodiment shows an example in which each radiator pipe 39 constituting the radiator 4 is inclined to facilitate return of the condensed liquid liquefied by the radiator 4. It is.

The refrigerant tank 3 is made of an extruded material 7 formed by extrusion from, for example, an aluminum block material.
And an end cap 22 which covers one open end (lower end in FIG. 7) of the extruded material 7. In the extruded material 7,
A plurality of vapor passages 9, condensate passages 10, and non-operating passages 33 are provided, which are partitioned by columns 30 to 32 extending in the vertical direction. The opening surface of each vapor passage 9 and the opening surface of the condensed liquid passage 10 are provided as a refrigerant tank side outlet 35 for the vapor refrigerant and a refrigerant tank side inlet 36 for the condensed liquid, respectively.

The end cap 22 is made of the same aluminum as the extruded member 7 and is covered on the outer periphery of the lower end of the extruded member 7 and joined by integral brazing. However, between the end cap 22 and the lower end surface of the extruded material 7, the vapor passage 9, the condensed liquid passage 10, and the non-operating passage 3 formed in the extruded material 7 are provided.
3 are formed to communicate with each other. As shown in FIG. 7, the end cap 22 is provided with a tube 49 for charging a refrigerant.
, Cleaning of the apparatus 1, injection of the refrigerant, and degassing are performed. In addition, degassing is performed by injecting the refrigerant, turning the entire device 1 upside down, placing the radiator 4 in a hot water tank (maintaining a temperature at which the saturated vapor pressure of the refrigerant is equal to or higher than the atmospheric pressure), and setting the device 1 This is performed by evaporating the refrigerant inside to expel air (the refrigerant gas is heavier than air). After degassing, the refrigerant is sealed in the apparatus 1 by caulking the end of the tube 49 and sealing off by welding or the like.

The radiator 4 is a so-called Dron cup type heat exchanger, and has two plates 50 as in the first embodiment.
A connecting pipe 51 (connecting member) formed by bonding
A plurality of radiator tubes 39 having the same hollow shape are laminated. The connection pipe 51 is placed over the outer periphery of the upper end of the refrigerant tank 3, and the inside thereof is separated by a separator 52.
Outflow chamber 511 communicating with the refrigerant tank side inflow port 35 and an inflow chamber 512 communicating with the refrigerant tank side inflow port 36 (see FIG. 10). FIG. 8 shows the outflow chamber 512 of the connecting pipe 51.
As shown in FIG. 10, a plurality of inner fins 53 are inserted. Each inner fin 53 is supported by a plurality of positioning ribs 50 a provided on the plate 50.

As shown in FIG. 10, the connection plate 34 is composed of two plate-like members, and forms a liquid refrigerant return section 341 by being bonded. Liquid refrigerant return section 341
Are air-tightly joined to the side wall of the connecting pipe 51, and are connected to the inflow side return chamber 461 communicating with each of the vapor passages 9 and the non-operating passages 33 through the refrigerant tank side outlet 35, and the condensate passage 10 through the refrigerant tank side inlet 36. An outlet-side return chamber 471 communicating with the
A return passage 421 that connects the inflow side return chamber 461 and the outflow side return chamber 471 is formed. An inner fin 43 is provided in the return passage 421 (see FIG. 11). The connection plate 34 includes a molding plate 40.
The same small-diameter opening 411 is opened, and the return chambers 461 and 471 communicate with the heat radiation tubes 39 through the small-diameter opening 411.

The liquid refrigerant return section 341 communicates with the refrigerant tank side outlet 35 of the refrigerant tank 3 and has an inlet side return chamber 461 (large-diameter opening, large-diameter portion) having a predetermined inner diameter (r1). The outflow side return chamber 471 (large diameter portion), the inflow side return chamber 461, and the outflow side return chamber 47 communicated with the inflow port 36.
1 and a return passage 421 communicating with the return passage 421. A small-diameter opening 4 having a diameter smaller than the inner diameter of the inflow-side return chamber 461 is provided on the side of the inflow-side return chamber 461 opposite to the refrigerant tank-side outlet 35.
11 (small diameter portion, suppression port) are formed.

The radiating tube 39 is formed in a hollow body by joining the outer peripheral edges of two forming plates 40 (for example, an aluminum plate) shown in FIG. 4, and has a small-diameter opening 41 at both ends. A passage and an outflow passage are provided. The heat radiating pipe 39 has a flat heat radiating passage 42 in its entire central portion, and its end portion has an inflow side communication chamber 44 having a large diameter.
(A space connected to the refrigerant tank side outlet 35 side) and an outflow side communication chamber 45 (a space connected to the refrigerant tank side inlet 36 side). Also, when viewed as a radiator 4,
By stacking a plurality of radiating tubes 39, a plurality of radiating passages 4 are formed.
2 and an inflow-side passage and an outflow-side passage connected to the ends of the heat radiation passages 42. Here, the inflow-side passage is configured by stacking a plurality of inflow-side communication chambers 44, and the outflow-side passage is configured by stacking a plurality of outflow-side communication chambers 45. The inflow-side passage and the outflow-side passage have small-diameter openings 41 between the inflow-side communication chambers 44 and the outflow-side communication chambers 45 with which the heat radiation passages 42 communicate. Thus, the inflow-side passage and the outflow-side passage have a plurality of large-diameter portions (r1) and small-diameter portions (r2) alternately arranged therein. The small-diameter opening 41 formed with the cutout hole also serves as a suppression port that suppresses the amount of liquid refrigerant entering between the adjacent inflow-side communication chambers 44.

As shown in FIG. 11, an inner fin 43 formed by shaping a thin aluminum plate into a corrugated shape is inserted into the flat heat radiation passage 42 of the heat radiation tube 39. Here, FIG.
2A is a plan view of the inner fin 43, and FIG. 2B is a cross-sectional view of the inner fin 43 taken along the line AA. Each radiator tube 39
As shown in FIG. 10, it is laminated on one side of the connecting pipe 51,
The small-diameter openings 41 communicate with each other.
The connecting pipe 51 and the heat radiating pipe 39 are formed by a small diameter opening 41 formed in the plate 50 (a plate on the heat radiating pipe 39 side) of the connecting pipe 51 and a small diameter opening 41 formed in the heat radiating pipe 39.
And communicate with each other through. However, each radiator tube 39
Are attached to the connecting pipe 51 such that the outflow side communication part 44 is higher than the inflow side communication part 45 in a state where the whole is inclined (see FIG. 7). In addition, plate 5
The rib 50b provided at 0 functions as a reinforcing rib for reinforcing the joint surface with the heat radiating tube 39.

Then, the small-diameter opening 41 of the heat radiation pipe 39 and the small-diameter opening 411 of the liquid refrigerant return portion 341 communicate with each other, and the inflow side return chamber 461 and the outflow side communication portion 44 communicate with each other. Further, the outflow side return chamber 471 and the inflow side communication part 45 are provided.
Are also communicated at the same time. Thus, the radiator 4 is configured. Next, the operation of the second embodiment will be described.

The refrigerant boiled by the heat generated from the IGBT module 2 is transferred to the vapor passages 9 as bubbles and rises in the respective vapor passages 9.
After flowing into the outflow chamber 511, the outflow chamber 511 further flows into the outflow-side passages (inflow-side return chamber 461 and the inflow-side communication chamber 44) of each of the radiator tubes 39, and flows into the radiator passages 4 of the respective radiator tubes 39.
Distributed to 2. The vapor refrigerant flowing through each heat radiation passage 42 is:
The cooling fan 5 (see FIG. 8) condenses on the inner wall surface and the inner fin surface of the heat radiation passage 42, which has a low temperature due to the air blown by the cooling fan 5, and releases condensed latent heat to form droplets of the heat radiation passage 42.
Flows into the outflow side passages (outflow side communication chamber 45 and outflow side return chamber 471) of each heat radiation tube 39 while flowing on the bottom surface of the heat radiation pipe 39. Thereafter, the condensed liquid flowing out of the outflow side passage to the inflow chamber of the connection pipe 51 flows from the refrigerant tank side inflow port 36 of the refrigerant tank 3 to the condensed liquid passage 1.
After flowing into the condensate passage 10 and flowing down the condensed liquid passage 10, the condensed liquid is again supplied to each steam passage 9 through the lower communication passage 38 in the end cap.

(Effect of the Second Embodiment) When the amount of heat radiation becomes large, many bubbles are blown up from the refrigerant tank, and the refrigerant in both gas and liquid phases enters the inflow side return chamber 461. The inflow-side return chamber 461 prevents the liquid refrigerant of the mixed refrigerant from entering the heat radiation passage by the small-diameter opening 411. That is, the liquid refrigerant of the mixed refrigerant is blocked by the small-diameter opening 411. The blocked liquid refrigerant is returned to the refrigerant tank through the return passage 421. Therefore, the mixed refrigerant that enters the heat radiation passage 42 through the small-diameter opening 411 has a reduced amount of the liquid refrigerant.
Thereby, the area for conducting the condensation heat in the heat radiation passage 42 can be increased.

From another point of view, the large-diameter portion (r1) and the small-diameter portion (r2) are alternately formed in the inlet side passage of the radiator 4 in the moving direction of the mixed refrigerant. The diameter portion (r2) suppresses the liquid refrigerant of the mixed refrigerant from entering the adjacent heat dissipation passage 42. Accordingly, the mixed refrigerant that enters the heat radiation passage 42 through the small-diameter portion (r2) has a reduced amount of the liquid refrigerant. Thereby, the area for conducting the condensation heat in the heat radiation passage can be increased.

In the second embodiment as well, as in the first embodiment, the small-diameter opening 41, which is a small-diameter portion, is provided in the inflow-side passage. Unevenness can be prevented, and there is also an effect of evenly distributing the refrigerant to each of the heat radiation passages 42, which can also prevent a decrease in heat radiation performance. Further, since the heat radiating pipe 39 is inclined with respect to the connecting pipe 51, the liquefied condensed refrigerant easily flows from the heat radiating passage 42 toward the refrigerant tank 3. Thus, the amount of condensed liquid that accumulates on the bottom surface of the heat radiation passage 42 is reduced, and the vapor refrigerant can be efficiently condensed.
As a result, the required amount of refrigerant can be reduced, and the cost can be reduced.

(Other effects of the second embodiment)
Since the steam passage 9 is divided into a plurality of passages by the support portion 31, the flow of the vapor refrigerant flowing through the steam passage 9 can be rectified, and the effective boiling area can be increased by the support portion 31 to improve the heat radiation performance. Further, it is effective in improving strength against positive and negative pressures in the refrigerant tank 3 and preventing deformation of a mounting surface on which the IGBT module 2 is mounted.

In the present invention, in addition to the configuration shown in the first and second embodiments, for example, the following configuration can be adopted. FIG. 13 shows the radiator 4
Are arranged on both sides of the connecting portion 34. With such a configuration, the heat radiation characteristics can be further improved. (Third Embodiment) FIG. 14 is a front view of a boiling cooling device 1 according to a third embodiment, and FIG. 15 is a side view of the boiling cooling device of the boiling cooling device shown in FIG.

This embodiment is a modification of the boiling cooling device shown in FIG. Hereinafter, the boiling cooling device of the present embodiment will be described focusing on the differences from the boiling cooling device of FIG. In this embodiment, portions having the same or equivalent operations as those in the embodiment shown in FIG. 7 are denoted by the same reference numerals as those in FIG. 7, and description thereof will be omitted. 14 and 15
7, the radiator 4 is a so-called Dron cup type heat exchanger, and has the same hollow shape as a connecting pipe 51 formed by bonding two plates 50 together as in the embodiment shown in FIG. A plurality of heat radiating tubes 39 are stacked.

The connecting pipe 51 is constituted by bonding two plates 50 shown in FIG. 16 (a), and the both ends thereof have boiling air in the refrigerant tank 3 as shown in FIG. 16 (b). Two delivery openings 5 for delivering the evolving vapor refrigerant to the radiator 4
41 and 542 and two return openings 544 and 545 for returning the condensed refrigerant condensed in the radiator 4 to the refrigerant tank 3. As shown in FIG. 14, the connection pipe 51 is covered on the outer periphery of the upper end of the refrigerant tank 3,
2 separates the refrigerant chamber 3 into an outflow chamber 511 (not shown) communicating with the refrigerant tank side outlet 35 and an inflow chamber 512 (not shown) communicating with the refrigerant tank side inlet 36.

Here, the dotted lines around the delivery opening 542 and the return opening 544 in FIG.
The projections near each opening shown in FIG. Also,
Holding members 543 and 546 are formed between the openings 541 and 542 and 544 and 545, respectively. Further, a plurality of inner fins 53 are provided in the inflow chamber of the connecting pipe 51.
Is inserted.

The heat radiating tube 39 is formed as a hollow body by joining the outer peripheral edges of two forming plates 40 (for example, an aluminum plate) shown in FIG. As shown in FIG. 2B, small-diameter openings 411 are provided at both ends.
412, 414, 415 are provided. Holding members 413 and 416 are formed between the small-diameter openings 411 and 412, respectively.

As shown in FIG. 15, the heat radiating tubes 39 are stacked on both sides of the connecting tube 51, and the heat radiating fins 16 are interposed between the stacked heat radiating tubes 39. Here, the small-diameter openings 411 and 415 are formed with projections as shown in the small-diameter openings in FIG. 17A, and the small-diameter openings 412 and 414 have widths so that the projections can be fitted. The hole is formed. When the plates 40 are stacked, the small-diameter opening 412 and the small-diameter opening 415 of another plate are fitted together, and the small-diameter opening 411 and the small-diameter opening 414 of another plate are fitted together. I have. After the fitting, the members are hermetically joined by brazing or the like. Thus, the plurality of plates 40 communicate with each other through the small-diameter openings 411, 412, 414, and 415 to form the radiation pipe 39.

Here, the connecting pipe 51 is connected to the delivery opening 54 thereof.
1, 542 and the return openings 544, 545 are the small-diameter openings 411, 412, 414, 415 of the forming plate 40.
Is connected to the heat radiating tube 39. Also, the outermost forming plate 40 of the radiator tube 39
Uses a plate without a small-diameter opening. Here, as the outermost plate, a forming plate 40 having a small-diameter opening is used, and the communication port 41 may be closed with an end plate (not shown) from the outside of the forming plate 40.

The heat radiating tube 39 has a flat heat radiating passage 42 in its entire central portion, and a plurality of heat radiating passages 42 are formed. An inner fin formed by shaping an aluminum thin plate into a corrugated shape as shown in FIG. From another viewpoint, the inflow-side passage is formed by laminating a plurality of inflow-side communication chambers 44 each of which is formed by two formed plates 40, and the outflow-side passage is formed by two formed plates 40. A plurality of outflow-side communication chambers 45 are stacked. The small-diameter openings 411, 412, 414, and 415 formed with the through holes also serve as suppression ports that suppress the amount of refrigerant entering between adjacent inflow-side communication chambers.

Here, the small-diameter openings 411, 412, 4
14, 415 (small diameter portion, suppression port) have a lateral diameter r
2 around which a large diameter opening (large diameter portion) having a lateral diameter r1 (where r1> r2)
Are formed. In addition, the small-diameter openings 411, 41
2, 414 and 415 have a vertical diameter r4, and a vertical diameter r3 (where r3> 2)
× r4), a large-diameter opening (large-diameter portion) is formed.

As in the case of FIG. 7, each of the heat radiating pipes 39 is attached in a state where the whole of the heat radiating pipes 39 is inclined with respect to the connecting pipe 51 such that the inflow side passage chamber 44 is higher than the outflow side communication chamber 45. Have been. Then, as shown in FIGS. 18A and 18B, the plate 40 constituting each heat radiation pipe 39 has the lowermost portion 411 a of the small-diameter opening 411 closer to the lowermost portion 40 a of the portion serving as the heat radiation passage 42. Is set to be lower by the distance d1, and the lowermost part 414a of the small-diameter opening 414 is also set to be lower by the distance d2. These d1 and d2 may be different or the same.

The operation of the present embodiment will be described. IGBT
The refrigerant boiled by the heat generated from the module (not shown) forms bubbles and rises in each vapor passage 9, and flows from the refrigerant tank side outlet 35 of the refrigerant tank 3 to the outlet chamber 5 of the connection pipe 51.
Flow into 11. Thereafter, the refrigerant flows from the outflow chamber 511 through the small-diameter openings 541 and 542, and further flows into the inflow-side passages (the inflow-side return chamber 461 and the inflow-side communication chamber 4) of each heat radiation pipe 39.
4) and is distributed to the heat radiation passage 42 of each heat radiation tube 39. The vapor refrigerant flowing through each heat radiation passage 42 is supplied to the cooling fan 5
(See FIG. 9), the air is condensed on the inner wall surface and the inner fin surface of the heat radiating passage 42, which has a low temperature, and discharges latent heat of condensation to form droplets.
And flows into the outflow-side passages (outflow-side return chamber 471 and outflow-side communication chamber 45) of each heat radiation tube 39. Thereafter, the refrigerant flows from the outlet side passage to the small-diameter opening 544 of the connecting pipe 51,
It flows to the inflow chamber 512 through 545. (In this case, most of the refrigerant flows near the lowermost portion of the lower small-diameter opening 544.) Further, the condensed liquid that has flowed out flows into the condensed liquid passage 10 from the refrigerant tank side inlet 36 of the refrigerant tank 3. After flowing down the condensed liquid passage 10 through the lower communication passage 38 in the end cap, it is again supplied to each steam passage 9.

(Effect of Third Embodiment) When the amount of heat radiation is increased, many bubbles are blown up from the refrigerant tank, and refrigerant in both gas and liquid phases enters the inflow side return chamber 461. The inflow-side return chamber 461 prevents the liquid refrigerant of the mixed refrigerant from entering the heat radiation passage by the small-diameter opening 414. That is, the liquid refrigerant of the mixed refrigerant is blocked by the small-diameter opening 414. The blocked liquid refrigerant is returned to the refrigerant tank through the return passage 421. Therefore, the mixed refrigerant that enters the heat radiation passage through the small-diameter opening 414 has a reduced amount of the liquid refrigerant. Thereby, the area for conducting the condensation heat in the heat radiation passage 42 can be increased.

In the third embodiment, the small-diameter openings 411, 412, 414, and 415, which are small-diameter portions, are provided in the inflow-side passage as in the first and second embodiments. It is possible to suppress intrusion of the liquid-phase refrigerant into the coolant 42. As a result, the heat can be transferred mainly by the condensation heat transfer in the heat dissipation passage 42, and the heat dissipation performance can be prevented from lowering. Further, by providing the small-diameter openings, it is possible to prevent the flow of the refrigerant into each of the heat radiating passages 42 from being biased, and to further distribute the refrigerant to each of the heat radiating passages 42 evenly. Can be prevented from decreasing.

Further, by inclining the heat radiating pipe 39 with respect to the connecting pipe 51, the liquefied condensate flows through the heat radiating passage 42 of the heat radiating pipe 39 from the outflow side communication part 44 to the inflow side communication part 45.
It becomes easier to flow toward. Thereby, the heat radiation passage 42
The amount of condensed liquid accumulated on the bottom surface of the liquid crystal is reduced, so that the vapor refrigerant can be efficiently condensed. As a result, the required amount of refrigerant can be reduced, and the cost can be reduced.

Here, the small-diameter opening 41 is also provided in the outflow-side passage.
In the case where 1, 412, 414, and 415 are formed, the refrigerant transmitted through the heat radiation passage 42 is blocked and accumulated in the small-diameter portion, and circulates in the boiling cooling device 1 and participates in the heat radiation. Although the amount may be reduced, the lowermost portions 411a and 414 of the small-diameter openings of the outflow-side passage are set lower than the lowermost portion 40a of the heat-radiating passage. The amount of the refrigerant that accumulates in the tank can be reduced. For this reason, the amount of the refrigerant sealed in the boiling cooling device 1 can be reduced, and the cost can be reduced.

The small-diameter openings 411, 412, 41
The periphery of 4, 415 is used as a bonding part, and a plurality of plates 40 are bonded at the bonding part to form a radiator. Holding members 413 and 4 are provided between the small-diameter openings.
Since the plate 40 is provided, a large uniform excess can be applied to the bonding portion when the plate 40 is bonded. Thereby, the airtightness when bonding and brazing can be improved, and as a result, the heat radiation performance can be improved.

(Fourth Embodiment) FIG. 19 is a front view of a boiling cooling device 1 according to a fourth embodiment. This embodiment is a modification of the boiling cooling device shown in FIG. Hereinafter, the boiling cooling device of the present embodiment will be described focusing on the differences from the boiling cooling device of FIG. In this embodiment, portions having the same or equivalent operations as those in the embodiment shown in FIG. 7 are denoted by the same reference numerals as those in FIG. 7, and description thereof will be omitted.

The connecting pipe 51 is vertically covered over the outer periphery of the upper end of the refrigerant tank 3, and the interior thereof is connected to the refrigerant chamber side inlet 36 and the refrigerant chamber side inlet 35 communicating with the refrigerant tank side outlet 35 of the refrigerant tank 3 by the separator 50 a. And an outflow chamber that leads to the
The liquid refrigerant return section 341 is configured by bonding two connection plates 34 together. The liquid refrigerant return part 341 is airtightly joined to the upper wall of the connecting pipe 51, and is condensed through one of the inflow side return chambers 461 communicating with the respective vapor passages 9 through the refrigerant tank side outlet 35 and the refrigerant tank side inlet 36. Liquid passage 1
0 and the inflow side return chamber 461,
1 and a heat radiation passage 421 communicating the outflow side return chamber 471. The connection plate 34 is provided with a small-diameter opening 411 similar to that of the forming plate 40, and through the small-diameter opening 411, each return chamber 461,
471 and each radiator tube 39 communicate with each other.

When the amount of heat radiation increases, many air bubbles are blown up from the refrigerant tank, and refrigerant in both gas and liquid phases enters the inflow-side return chamber 461. The inflow-side return chamber 461 prevents the liquid refrigerant of the mixed refrigerant from entering the heat radiation passage by the small-diameter opening 411. That is, the small-diameter opening 41
1 blocks the liquid refrigerant of the mixed refrigerant. The blocked liquid refrigerant is returned to the refrigerant tank through the return passage 421. Therefore, the amount of the liquid refrigerant in the mixed refrigerant that enters the heat radiation passage through the small-diameter opening 411 is reduced. Thereby, the area for conducting the condensation heat in the heat radiation passage 42 can be increased.

Further, in the refrigerant in the refrigerant tank 3, when the amount of heat radiation increases, bubbles increase inside the refrigerant and the liquid level rises. The lowermost portion of the opening position of the small-diameter opening 411 is the inflow-side return chamber 4.
Since it is set to be smaller than the bottom surface of 61 by a predetermined diameter (r1-r2), it becomes a clog when the liquid level rises. Accordingly, it is possible to suppress the liquid refrigerant from entering the heat radiation passage.

(Other Effects of First to Fourth Embodiments) (1) The radiator can be constituted by stacking a plurality of radiating tubes of the same hollow shape on a connecting member connected to the refrigerant tank. In addition, even when the total number of heating elements increases due to an increase in the number of heat generating elements attached, the capacity of the radiator can be easily changed. That is, since the radiator capacity can be easily increased by sequentially stacking the same hollow radiator tubes, a radiator having a capacity corresponding to the total heat generation amount can be provided at low cost.

(2) The refrigerant tank 3 has a lower communication passage 38 therein for communicating a vapor passage and a condensate passage at a lower portion in the refrigerant tank.
Therefore, the cooled refrigerant is always supplied to the vapor passage from the condensate passage. Therefore, flooding in the refrigerant tank (interference between the vapor refrigerant and the condensed liquid refrigerant at the time of movement can be prevented. (3) Since the radiator pipe 39 is connected to the refrigerant tank 3 via the connection pipe 51, the connection is made. Depending on the shape of the tube 51, the mounting direction and the position of the heat radiating tube 39 can be appropriately changed, so that the degree of freedom in design is improved, and the size can be reduced.

(4) Since the bottom surface is inclined downward from the outflow side communication portion 44 to the inflow side communication portion 45, the condensate flowing through the heat radiation passage flows from the outflow side communication portion to the inflow side communication portion. Easy to flow. For this reason, the amount of the condensed liquid accumulated on the bottom surface of the heat radiation passage is reduced, and the vapor refrigerant can be efficiently condensed. (5) Since the refrigerant tank 3 is made of extruded extruded material, productivity is improved.

(6) Since the partition wall is provided integrally with the extruded material and divides the inside of the refrigerant chamber, the vapor passage 9 and the condensate passage 10 can be easily formed. (7) Since the plurality of steam passages 9 can be communicated with the steam refrigerant tank side outlet 35 only by removing the upper part of the support portion 31 provided in the extruded material, the cost can be reduced without adding special parts. Can control the circulation of the refrigerant.

(8) By removing the lower part of the column provided in the extruded material and joining the closing member to the lower end surface of the extruded material, the vapor passage and the condensed liquid passage communicate with each other at the lower part in the refrigerant chamber. can do. For this reason, since the closing member can be formed into a simple shape (for example, a simple flat plate), the manufacturing of the closing member becomes easy. (9) In the coolant tank 3, a coolant chamber can be provided for each heating element in correspondence with a case where a plurality of heating elements are attached. In this case, by communicating the respective refrigerant chambers, the circulation of the refrigerant is uniformly performed in the entire refrigerant tank, so that a decrease in the heat radiation performance due to the uneven distribution of the condensed refrigerant can be prevented.

(10) Since the amount of the refrigerant to be used can be reduced by making the refrigerant tank flat, the cost can be kept low even when an expensive fluorocarbon-based refrigerant is used, for example. (11) The vapor passage and the condensate passage may be formed by the refrigerant flow control plate disposed in the refrigerant chamber. In this case, in addition to the effect of preventing flooding, the refrigerant flow control plate is arranged in contact with the inner wall surface of the refrigerant chamber, thereby improving the rigidity of the refrigerant chamber and improving the heat radiation performance by increasing the heat radiation area of the refrigerant chamber. it can.

(12) Not only the refrigerant tank but also the radiator is formed by using an extruded material extruded integrally with the refrigerant tank, so that the cost of the radiator can be reduced as compared with the conventional apparatus. In addition, since there is no need for a step of assembling the radiator and the coolant tank, the cost of the entire apparatus can be reduced. (13) The radiator 4 is formed by bonding a plurality of plate-like members having a bonding portion at the bonding portion, and the bonding portion is formed by bending and raising the plate-like member. Therefore, a radiator can be easily formed.

Although the present embodiment has been described using a heating element as the high-temperature medium, the high-temperature medium may be a high-temperature fluid such as a high-temperature gas or a high-temperature liquid.
In this case, for example, heat absorbing fins are provided at the semiconductor element mounting portion in the present embodiment. Then, the heating element or the like is arranged at a remote place, the high-temperature fluid surrounding the heating element is circulated, and the high-temperature fluid is cooled by absorbing heat of the high-temperature fluid by the heat absorbing fins. Thus, the heating element can be cooled via the high-temperature fluid.

[Brief description of the drawings]

FIG. 1 is a side view of a boiling cooling device according to a first embodiment.

FIG. 2 is a sectional view taken along the line BB of the boiling cooling device shown in FIG.

FIG. 3 is a sectional view of the boiling cooling device shown in FIG.

FIG. 4A is a side view of a forming plate constituting a heat radiating tube, and FIG. 4B is a plan view of FIG.

FIG. 5 is a sectional view taken along line DD of the boiling cooling device shown in FIG. 1;

FIG. 6 is an explanatory diagram of the boiling cooling device shown in FIG. 1;

FIG. 7 is a perspective view of a boiling cooling device according to a second embodiment.

FIG. 8 is a partial cross-sectional view taken along the line II ′ of the boiling cooling device shown in FIG. 7;

FIG. 9 is a partial cross-sectional view taken along the line II-II ′ of the boiling cooling device shown in FIG. 7;

FIG. 10 is a partial sectional view taken along the line III-III ′ of the boiling cooling device shown in FIG. 7;

11 is an explanatory view of the inside of a return passage and the inside of a heat radiation passage of the boiling cooling device shown in FIG. 7;

12A is a front view of an inner fin, and FIG. 12B is a cross-sectional view taken along line AA of FIG.

FIG. 13 is a side view of a boiling cooling device according to another embodiment.

FIG. 14 is a front view of a boiling cooling device according to a third embodiment.

FIG. 15 is a side view of the boiling cooling device shown in FIG. 14;

FIG. 16A is a side view of a forming plate constituting a connecting pipe, and FIG. 16B is a plan view of FIG.

FIG. 17 (a) is a side view of a forming plate constituting a heat radiation tube, and FIG. 17 (b) is a plan view of FIG. 17 (a).

18 (a) and (b) are partially enlarged views of the forming plate shown in FIG.

FIG. 19 is a front view of a boiling cooling device according to a fourth embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Boiling cooling device 2 IGBT module (heating element) 3 Refrigerant tank 4 Radiator 6 Bolt 7 Extruded material 7a Thick part 9 Steam passage 10 Condensate passage 22, 22, 22a, 22b End cap 26 Attachment member 26a Female screw 30, Column 31, 32 Support part 34 Connection plate 341 Liquid refrigerant return part (adhesion amount reducing means) 35 Refrigerant tank side outlet 36 Refrigerant tank side inlet 38 Lower communication path 39 Heat radiating pipe 41, 411, 412, 414, 415 Small aperture ( 411a, 414a Bottom of small-diameter opening 42 Heat dissipation passage 42a Bottom of heat dissipation passage 421 Return passage 44 Outflow-side communication chamber (inflow-side passage) 45 Inflow-side communication chamber (outflow-side passage) 461 Inflow-side return chamber (inflow-side passage) 471 Outflow-side return chamber (outflow-side passage) 51 Connecting pipe 52 Separator 541, 54 Sending the openings 544 and 545 return opening

Claims (19)

[Claims] 1. A refrigerant that receives heat from a high-temperature medium, contains therein a liquid refrigerant that partially evaporates and turns into a gaseous refrigerant, and flows out a mixed refrigerant of the vaporized gaseous refrigerant and the liquid refrigerant. A tank (3) provided in communication with the refrigerant tank, wherein the mixed refrigerant flows in from the refrigerant tank, and radiates heat of the mixed refrigerant to a low-temperature medium to condense and liquefy the gaseous refrigerant; A radiator (4) for returning the refrigerant and the condensed and liquefied refrigerant to the refrigerant tank, wherein the radiator (4) receives the mixed refrigerant from the refrigerant tank (3), and The inflow-side passage (4) in which large-diameter portions (r1) and small-diameter portions (r2) are alternately formed in the movement direction of
4, 461), and an outflow-side passageway (4, 4) through which the refrigerant flows out to the refrigerant tank (3).
5, 471), and a plurality of heat radiation passages (421, 42) for communicating the inflow-side passage with the inflow-side passage. 2. The outflow-side passage has a large-diameter portion and a small-diameter portion alternately formed in a moving direction of the vaporized refrigerant, and each of the plurality of heat-radiating passages is provided with the large-diameter portion of the inflow-side passage. The boiling cooling device according to claim 1, wherein a specific one of the diameter portions and a specific one of the large diameter portions of the outflow-side passage communicate with each other. 3. The refrigerant tank communicates with a vapor passage (9) which rises the gaseous refrigerant and the liquid refrigerant vaporized by the heat of the high-temperature medium and guides them to the inflow-side passage, and the outflow-side passage. 3. The boiling cooling device according to claim 1, further comprising a condensed liquid passage through which the refrigerant cooled by the radiator flows. 4. A refrigerant that receives heat from a high-temperature medium and contains therein a liquid refrigerant that partially evaporates and turns into a gas refrigerant, and a mixed refrigerant of the vaporized gas refrigerant and the liquid refrigerant flows out. A refrigerant tank (3) having a tank-side outlet, and provided in communication with the refrigerant tank, wherein the mixed refrigerant flows in from the refrigerant tank, and radiates heat of the mixed refrigerant to a low-temperature medium to thereby release the gas refrigerant. A radiator (4) for condensing and liquefying the liquid refrigerant and returning the liquid refrigerant and the condensed and liquefied refrigerant to the refrigerant tank. The radiator (4) is provided with a refrigerant tank side outlet (35) in the refrigerant tank. ), And has a small-diameter opening (411) having a smaller diameter (r2) than its own inner diameter (r1), and the liquid refrigerant of the mixed refrigerant is blocked by the small-diameter opening. Side return room (461) and the inflow side return room (46 Return passage) connected to the liquid refrigerant dammed to return to the coolant tank (421), the liquid refrigerant return unit (341) having the said small-diameter opening of the liquid refrigerant return unit (341) (4
11), the inflow side return chamber (46)
1) is connected to the refrigerant tank side outlet (35) through
A cooling passage for introducing the gaseous refrigerant of the mixed refrigerant, condensing and liquefying the gaseous refrigerant, and returning the refrigerant to the refrigerant tank (3). 5. The inflow-side return chamber of the liquid refrigerant return portion (341) has a bottom surface, and the lowermost portion of the small-diameter opening portion at an opening position is set above the bottom surface by a predetermined height. The boiling cooling device according to claim 4, wherein: 6. The cooling apparatus according to claim 4, wherein the small-diameter opening is a substantially elliptical or substantially rectangular hole. 7. The refrigerant tank has a refrigerant tank side inlet (36) through which the liquid refrigerant and the condensed and liquefied refrigerant flow from the radiator, and the liquid refrigerant return section (341) An outlet-side return chamber (471) connected to the refrigerant tank-side inlet, wherein the return passage and the heat radiation passage are connected to the refrigerant tank via the outlet-side return chamber. The boiling cooling device according to any one of claims 4 to 6. 8. The refrigerant tank has therein a vapor passage (9) which rises the gaseous refrigerant and the liquid refrigerant vaporized by the heat of the high-temperature medium and guides them to the refrigerant tank side outlet (35);
The boiling cooling device according to claim 7, further comprising a condensed liquid passage (10) that communicates with the refrigerant tank side inlet and through which the refrigerant cooled by the radiator flows. 9. The heat radiation passage (42) has a bottom surface inside, and the bottom surface is inclined downward from the refrigerant tank side outlet (35) side to the refrigerant tank side inlet (36) side. The boiling cooling device according to any one of claims 7 and 8, wherein 10. A liquid refrigerant, which receives heat from a high-temperature medium and partially evaporates to become a gas refrigerant, is housed therein,
A refrigerant tank (3) for flowing out a mixed refrigerant of the vaporized gas refrigerant and the liquid refrigerant, and a refrigerant tank provided in communication with the refrigerant tank, wherein the mixed refrigerant flows in from the refrigerant tank and heats the mixed refrigerant. A radiator (4) for condensing and liquefying the gaseous refrigerant by radiating heat to a low-temperature medium and returning the liquid refrigerant and the condensed and liquefied refrigerant to the refrigerant tank; And the first large-diameter portion (461) and the small-diameter portion (41) in the moving direction of the mixed refrigerant.
1) and the second large-diameter portion (44) are communicated with the inflow-side passages (461, 411, 44) formed in this order, the first large-diameter portion (461), and A return passage (421) through which the liquid refrigerant blocked by the small-diameter portion flows, and a gas refrigerant that is communicated with the second large-diameter portion (44) and that has passed through the small-diameter portion of the mixed refrigerant. A radiating passage (42) for introducing and condensing and liquefying the gaseous refrigerant, and an outflow side passage (45, which communicates with the return passage and the radiating passage and returns the liquid refrigerant and the condensed and liquefied refrigerant to the refrigerant tank. 471) A boiling cooling device comprising: 11. The first large-diameter portion (461) has a bottom surface, and the lowermost portion of the opening position of the small-diameter portion (411) is set above the bottom surface by a predetermined height. The boiling cooling device according to claim 10, characterized in that: 12. The cooling apparatus according to claim 10, wherein the small-diameter portion (411) is a substantially elliptical or substantially rectangular hole. 13. The refrigerant tank has therein a vapor passage (9) which rises the gaseous refrigerant and the liquid refrigerant vaporized by the heat of the high-temperature medium and guides them to the refrigerant tank side outlet (35); A condensed liquid passage (10) that communicates with the refrigerant tank side inlet and through which the refrigerant cooled by the radiator flows down;
The boiling cooling device according to any one of claims 10 to 12, comprising: 14. The heat-radiating passage has a bottom surface inside, and the outlet-side passage (45, 471) has a large-diameter portion and a small-diameter portion alternately formed in the moving direction of the vaporized refrigerant. The lowermost portion of the small-diameter portion of the outflow-side passage is set lower than the lowermost portion of the heat-radiating passage.
The boiling cooling device according to claim 13. 15. A refrigerant tank (3) that receives a heat from a high-temperature medium and partially accommodates a liquid refrigerant that becomes a gaseous refrigerant by boiling and evaporating, and is provided in communication with the refrigerant tank; A mixed refrigerant of the gas refrigerant and the liquid refrigerant vaporized in the refrigerant tank is introduced from the refrigerant tank, and the gas refrigerant is condensed and liquefied by radiating heat of the mixed refrigerant to a low-temperature medium. A radiator (4) for returning the condensed and liquefied refrigerant to the refrigerant tank, wherein the refrigerant tank has a vapor passage (9) in which the refrigerant vaporized by the heat of the heating element rises in the refrigerant tank; ), And a condensate passage (10) through which the refrigerant condensed and liquefied by the radiator flows down in the refrigerant tank. The radiator communicates with the vapor passage and has a plurality of inflow-side communication chambers (461, 44). ), Said condensate passage A plurality of outlet side communicating chamber with leading (47
1, 45), and a plurality of heat radiation passages (4) for communicating a specific inflow side communication chamber with a specific outflow side communication chamber.
21, 42) and the plurality of inflow-side communication chambers, and a suppression port (411, 41) for suppressing the flow of the liquid refrigerant into an adjacent inflow-side communication chamber. Boiling cooling device. 16. The boiling cooling apparatus according to claim 15, wherein the suppression port is a substantially elliptical or substantially rectangular hole. 17. The heat radiation passage has a bottom surface inside, and the bottom surface is inclined downward from the inflow side passage side to the outflow side passage side.
The boiling cooling device according to claim 16. 18. The radiator is formed by bonding a plurality of plate members having a bonding portion at the bonding portion, and the bonding portion bends and raises the plate member. The boiling cooling device according to any one of claims 1 to 17, wherein the boiling cooling device is formed by: 19. A liquid refrigerant, which receives heat from a high-temperature medium and partially evaporates to become a gas refrigerant, is housed therein,
A refrigerant tank (3) for flowing out a mixed refrigerant of the vaporized gas refrigerant and the liquid refrigerant, and a refrigerant tank provided in communication with the refrigerant tank, wherein the mixed refrigerant flows in from the refrigerant tank and heats the mixed refrigerant. A radiator (4) for condensing and liquefying the gaseous refrigerant by radiating heat to the low-temperature medium and returning the liquid refrigerant and the condensed and liquefied refrigerant to the refrigerant tank; A heat radiation passage for condensing and liquefying the refrigerant; and an adhesion amount reducing means (461, 421, 411) for reducing the amount of the liquid refrigerant flowing from the refrigerant tank (3) that adheres to the inner wall of the heat radiation passage. And a boiling cooling device comprising: