JP2021132168A - Boiling cooler - Google Patents

Abstract

To provide a boiling cooler capable of obtaining excellent cooling performance even when the size is reduced.SOLUTION: A boiling cooler includes a heat receiving unit that includes a storage chamber that stores a refrigerant and receives heat from a heating element, a heat radiating unit that includes a first condensing chamber and a second condensing chamber having different heat radiating conditions or heat radiating properties, and radiates heat from the heat receiving unit by radiating heat from the refrigerant to an external fluid in the first condensing chamber and the second condensing chamber, and a heat transfer unit that includes a plurality of first pipelines communicating the storage chamber and the first condensing chamber, and a plurality of second pipelines communicating the storage chamber and the second condensing chamber, and transports heat from the heat receiving unit to the heat radiating unit using the self-excited vibration of the refrigerant in the plurality of first pipelines and the plurality of second pipelines.SELECTED DRAWING: Figure 3

Description

The present invention relates to a boiling cooler.

A boiling cooler is known that cools a heating element by utilizing heat transport by latent heat accompanying boiling of a refrigerant.

For example, the cooler described in Patent Document 1 has a heat receiving portion, a heat radiating portion, and a first connecting portion and a second connecting portion connecting them. Here, the heat receiving unit stores the refrigerant, receives the heat from the object to be cooled, and vaporizes the refrigerant by the heat. The first connecting portion transports the refrigerant vaporized in the heat receiving portion to the heat radiating portion. The heat radiating unit radiates heat from the refrigerant to condense and liquefy the refrigerant. The second connecting portion transports the refrigerant condensed and liquefied by the heat radiating portion to the heat receiving portion.

International Publication No. 2015/146110

As described above, the cooler described in Patent Document 1 circulates or moves the refrigerant between the heat receiving portion and the heat radiating portion by the salmon siphon method utilizing the density difference between the liquid phase and the gas phase of the refrigerant. .. Therefore, in the cooler described in Patent Document 1, in order to reduce the size, the resistance in the circulation flow path of the refrigerant increases, the position head between the heat receiving portion and the heat radiating portion decreases, and the position head decreases. Since the vaporized refrigerant is likely to be mixed into the second connecting portion, the refrigerant cannot be smoothly circulated or moved. As a result, there is a problem that the cooling capacity is lowered.

In order to solve the above problems, the boiling cooler according to one aspect of the present invention has a storage chamber for storing a fluid, and has different heat dissipation conditions or heat dissipation properties from the heat receiving unit that receives heat from the heating element. A heat radiating section having a first condensing chamber and a second condensing chamber, and radiating heat from the heat receiving portion by radiating heat from the refrigerant to an external fluid in the first condensing chamber and the second condensing chamber, and the accommodating chamber. It has a plurality of first pipelines that communicate with the first condensing chamber, and a plurality of second pipelines that communicate the accommodating chamber and the second condensing chamber. It has a heat transfer unit that transports heat from the heat receiving unit to the heat radiating unit by using the self-excited vibration of the fluid in the plurality of second pipelines.

It is a perspective view which shows the schematic structure of the boiling cooler which concerns on 1st Embodiment. It is a top view of the boiling cooler which concerns on 1st Embodiment. FIG. 2 is a cross-sectional view taken along the line AA in FIG. It is a figure which shows the liquid column and the air column of the refrigerant in the conduit of a heat transfer part. It is a top view of the boiling cooler which concerns on 2nd Embodiment. FIG. 5 is a cross-sectional view taken along the line BB in FIG. It is a figure for demonstrating the operation of the heat radiation side tube body. It is sectional drawing of the boiling cooler which concerns on 3rd Embodiment.

Hereinafter, preferred embodiments according to the present invention will be described with reference to the accompanying drawings. In the drawings, the dimensions or scale of each part are appropriately different from the actual ones, and some parts are schematically shown for easy understanding. Further, the scope of the present invention is not limited to these forms unless it is stated in the following description that the present invention is particularly limited.

1. 1. First Embodiment 1-1. Schematic FIG. 1 of the boiling cooler 1 is a perspective view showing a schematic configuration of the boiling cooler 1 according to the first embodiment. The boiling cooler 1 is used for cooling in a power electronics product such as an inverter or a rectifier mounted on a railroad vehicle, an automobile, a household electric machine, or the like. Power electronics products include, for example, power semiconductor devices such as diodes or IGBTs (Insulated Gate Bipolar Transistors). The power semiconductor element is an example of a heating element that is an object of cooling in the boiling cooler 1.

In the following, for convenience of explanation, the "X-axis", "Y-axis", and "Z-axis" that are orthogonal to each other will be described as appropriate. Further, one direction along the X axis is referred to as "X1 direction", and the direction opposite to the X1 direction is referred to as "X2 direction". Similarly, one direction along the Y axis is referred to as "Y1 direction", and the direction opposite to the Y1 direction is referred to as "Y2 direction". One direction along the Z axis is referred to as "Z1 direction", and the direction opposite to the Z1 direction is referred to as "Z2 direction". Here, the Z axis is an axis parallel to the normal line of the first surface F1 or the second surface F2 of the heat receiving portion 10 described later. Further, viewing in the Z1 direction or the Z2 direction is referred to as "plan view".

The boiling cooler 1 is a cooler that cools a heating element (not shown) by utilizing heat transport by latent heat accompanying boiling of the refrigerant RE. In particular, the boiling cooler 1 is a self-excited oscillating type cooler that causes the refrigerant RE to generate a vibrating flow due to a pressure difference due to a phase change between the gas phase and the liquid phase of the refrigerant RE. That is, the boiling cooler 1 cools not only the latent heat transport due to the phase change of the refrigerant RE but also the sensible heat transport due to the temperature change accompanying the movement of the liquid of the refrigerant RE.

As shown in FIG. 1, the boiling cooler 1 has a heat receiving unit 10, a heat radiating unit 20, and a heat transmitting unit 30. First, to briefly explain each part of the boiling cooler 1, the heat receiving part 10 is a structure that receives heat from a heating element (not shown). The heat receiving unit 10 is provided with a storage chamber S1 as a space for storing the refrigerant RE. The heat radiating unit 20 is a structure that dissipates heat from the heat receiving unit 10. The heat radiating unit 20 is provided with a plurality of condensing chambers S2 as a space for condensing the refrigerant RE from the vaporized state. In the example shown in FIG. 1, the heat radiating unit 20 has a plurality of heat radiating fins 22 for radiating heat from the plurality of condensing chambers S2. The heat transfer unit 30 is a structure that transfers heat from the heat receiving unit 10 to the heat radiating unit 20. In the heat transfer section 30, two pipelines S3 are formed in each of the condensing chambers S2 as a space for communicating the accommodating chamber S1 and the condensing chamber S2. In the example shown in FIG. 1, the heat transfer unit 30 has a plurality of pipe bodies 31 forming the pipe line S3.

Here, the plurality of condensing chambers S2 included in the heat radiating unit 20 include a plurality of condensing chambers S2 having different heat radiating conditions or heat radiating properties. A temperature difference is likely to occur between a plurality of condensing chambers S2 having different heat dissipation conditions or heat dissipation properties, and the pressure tends to be non-uniform accordingly. Therefore, the above-mentioned vibration flow is likely to occur in each of the plurality of condensing chambers S2. As a result, excellent heat dissipation characteristics of the boiling cooler 1 can be obtained. In addition, "different heat dissipation" means that the efficiency of heat exchange to be compared is different. “Different heat dissipation conditions” means that the conditions relating to the efficiency of heat exchange to be compared are different.

In the example shown in FIG. 1, the number of the condensing chambers S2 included in the heat radiating unit 20 is eight. Therefore, the number of pipes 31 included in the heat transfer unit 30 is 16. Further, since two sets of the tube bodies 31 are provided for each condensing chamber S2, the number of the sets of the tube bodies 31 included in the heat transfer unit 30 is eight. In the following, the eight condensing chambers S2 included in the heat radiating unit 20 may be referred to as condensing chambers S2-1 to S2_8. Similarly, the eight sets of pipes 31 included in the heat transfer unit 30 may be referred to as pipes 31_1 to 31_8. The pipeline S3 may also be referred to as pipelines S3-1 to S3_8, corresponding to the pipe bodies 31_1 to 31_8. Hereinafter, each part of the boiling cooler 1 will be described in sequence.

1-2. Detailed FIG. 2 of each part of the boiling cooler 1 is a plan view of the boiling cooler 1 according to the first embodiment. FIG. 3 is a cross-sectional view taken along the line AA in FIG.

The heat receiving unit 10 has a storage chamber S1 for storing the refrigerant RE, and is a container that receives heat from a heating element (not shown). The heat receiving unit 10 is made of a material having excellent thermal conductivity. Specific constituent materials of the heat receiving unit 10 include metal materials such as copper, aluminum, and alloys of any of these.

The refrigerant RE is not particularly limited, but for example, an aqueous refrigerant such as water, an alcohol-based refrigerant such as methanol, a ketone-based refrigerant such as acetone, a glycol-based refrigerant such as ethylene glycol, a fluorocarbon-based refrigerant such as fluorocarbon, and HFC134a. Freon-based refrigerants such as, and hydrocarbon-based refrigerants such as butane can be mentioned. If necessary, a surfactant such as a fluorine-based surfactant, a silicone-based surfactant, or a hydrocarbon-based surfactant may be added to the refrigerant RE. Further, the refrigerant RE may be a combination of two or more of the above-mentioned refrigerants.

As shown in FIG. 3, the outer shape of the heat receiving portion 10 has a substantially plate shape having a first surface F1 and a second surface F2 on the opposite side of the first surface F1. The heat receiving portion 10 shown in FIGS. 1 and 2 is provided with a plurality of holes HM for fixing to the object to be cooled by screwing. The plurality of holes HM are not limited to the form shown in FIG. 1, and may be arbitrarily provided, and may be omitted if necessary.

The first surface F1 is a surface that is thermally connected to a heating element (not shown). The second surface F2 is a surface to which the heat transfer unit 30 is connected. The term "thermally connected" means that any of the following conditions a, b, or c is satisfied. Condition a: The two members are in direct physical contact. Condition b: Two members are arranged with a gap of 50 μm or less. Condition c: Two members are physically connected via another member having a thermal conductivity of ^{10 W · m -1} · K ^{-1 or higher.} A heat transfer grease, an adhesive, or the like may be present between the two members under each condition. In this case, the adhesive preferably contains a thermally conductive filler or the like from the viewpoint of enhancing the thermal conductivity.

In the example shown in FIG. 3, each of the first surface F1 and the second surface F2 is a plane orthogonal to the Z axis. The shapes of the first surface F1 and the second surface F2 are not limited to the shapes shown in FIG. 3, but are determined according to the shape of the object to be cooled and the like, and may have a curved portion, for example.

As shown in FIG. 3, the heat receiving portion 10 has a bottom plate 11, a top plate 12, and a side wall 13. Each of the bottom plate 11 and the top plate 12 is a flat plate extending in a direction orthogonal to the Z axis. However, the top plate 12 is provided with a plurality of through holes 14 for connecting the ends of the plurality of pipes 31 included in the heat transfer unit 30. The bottom plate 11 and the top plate 12 are arranged parallel to each other. The side wall 13 connects the outer circumferences of the bottom plate 11 and the top plate 12 over the entire circumference. Here, the surface of the bottom plate 11 in the Z2 direction is the first surface F1. The surface of the top plate 12 in the Z1 direction is the second surface F2.

The bottom plate 11, the top plate 12, and the side wall 13 may each be composed of separate members, or two or more of the bottom plate 11, the top plate 12, and the side wall 13 may be integrally formed. Further, the constituent materials of the bottom plate 11, the top plate 12 and the side wall 13 may be the same or different from each other.

The heat radiating unit 20 shown in FIG. 3 has a plurality of condensing chambers S2, and the refrigerant RE is radiated to the outside by heat exchange with an external fluid in the plurality of condensing chambers S2 to condense and liquefy the refrigerant RE from a gaseous state. The body. The external fluid is not particularly limited and may be a liquid or a gas, but is typically, for example, air.

The heat radiating unit 20 of the present embodiment has a cylinder 21_1 to 21_8 and a plurality of heat radiating fins 22. The tubular body 21_1 is a container that forms the condensing chamber S2_1 as an internal space. Specifically, the tubular body 21_1 has a tubular portion and a pair of plate portions that close both ends of the tubular portion. However, one of the pair of plate portions is provided with a hole for connecting the two pipe bodies 31. Similarly, the tubular body 21_2 to 21_8 is a container that forms the condensing chamber S2_2 to S2_8 as an internal space.

In the present embodiment, the internal space of each cylinder 21, that is, each condensation chamber S2 has a columnar shape. Therefore, the plan-view shapes of the plurality of condensing chambers S2 provided in the heat radiating unit 20 are circular, and have the same shape as each other. However, the areas of the condensing chambers S2_1, S2_4, and S2_6 in a plan view are equal to each other, but different from the other condensing chambers S2. Further, the areas of the condensing chambers S2_2, S2_5 and S2_7 in a plan view are equal to each other, but different from the other condensing chambers S2. Further, the areas of the condensing chambers S2_3 and S2_8 in a plan view are equal to each other, but different from the other condensing chambers S2.

Here, as shown in FIG. 2, in a plan view, the areas of the condensing chambers S2_1, S2_4, and S2_6 are larger than the areas of the condensing chambers S2_2, S2_3, S2_5, S2_7, and S2_8, respectively. Further, in a plan view, the areas of the condensing chambers S2_2, S2_5 and S2_7 are larger than the areas of the condensing chambers S2_3 and S2_8, respectively.

Further, in a plan view, the condensing chambers S2-1 to S2_3 are arranged in the X2 direction in this order. Further, in a plan view, the condensing chambers S2_4 and S2_5 are arranged in the X2 direction in this order. Further, in a plan view, the condensing chambers S2_6 to S2_8 are arranged in the X2 direction in this order. Here, the group consisting of the condensing chambers S2-1 to S2_3, the group consisting of the condensing chambers S2_4 and S2_5, and the group consisting of the condensing chambers S2_6 to S2_8 are arranged in this order in the Y2 direction.

In this embodiment, the lengths of the condensing chambers S2-1 to S2_8 along the Z axis are equal to each other as shown in FIG. The lengths of the condensing chambers S2-1 to S2_8 along the Z axis may be different from each other.

As can be seen from the above, the volumes of the condensing chambers S2_1, S2_4 and S2_6 are equal to each other but different from the other condensing chambers S2. Further, the volumes of the condensing chambers S2_2, S2_5 and S2_7 are equal to each other, but different from the other condensing chambers S2. Further, the volumes of the condensing chambers S2_3 and S2_8 are equal to each other but different from the other condensing chambers S2.

Here, the volumes of the condensing chambers S2_1, S2_4, and S2_6 are larger than the volumes of the condensing chambers S2_2, S2_3, S2_5, S2_7, and S2_8, respectively. Further, the volumes of the condensing chambers S2_2, S2_5 and S2_7 are larger than the volumes of the condensing chambers S2_3 and S2_8, respectively.

The plurality of condensing chambers S2 having different volumes have different heat capacities. Therefore, in the plurality of condensing chambers S2, heat dissipation conditions or heat dissipation properties are different from each other, so that a temperature difference tends to occur easily. Further, since the surface areas in the outer diameters of the condensing chambers S2-1 to S2_3, the condensing chambers S2_4 and S2_5, and the condensing chambers S2_6 to S2_8 are different, the heat radiating conditions or the heat radiating properties are different from each other, and a temperature difference is likely to occur.

The plurality of heat radiating fins 22 provided in the heat radiating unit 20 are thermally connected to the above-mentioned cylinders 21_1 to 21_8. Each heat radiation fin 22 is made of a material having excellent thermal conductivity. Specific constituent materials of the heat radiating fin 22 include, for example, a metal material such as copper, aluminum, or an alloy thereof.

In the example shown in FIG. 3, each heat radiation fin 22 has a flat plate shape. Further, the plurality of heat radiation fins 22 are arranged so as to be spaced apart from each other in the thickness direction. The heat radiation fins 22 of the present embodiment are arranged so as to overlap each other over almost the entire range of the heat receiving portion 10 in a plan view. Here, each heat radiation fin 22 is provided with a hole for inserting the above-mentioned tubular bodies 21_1 to 21_8. Further, the heat radiation fins 22 are fixed to the cylinders 21_1 to 21_8 by adhesive, screwing, welding or the like so as to be thermally connected to the cylinders 21_1 to 21_8.

The shape, number, and the like of the heat radiation fins 22 are not limited to the example shown in FIG. 3, and are arbitrary. Further, each heat radiation fin 22 may be individually provided for each condensation chamber S2. In this case, the configurations of the plurality of heat radiation fins 22 for each of the condensation chambers S2 may be the same or different from each other. Further, the heat radiation fins 22 may be provided as needed or may be omitted.

The heat transfer unit 30 is a structure having a plurality of pipelines S3 and transferring heat from the heat receiving unit 10 to the heat radiating unit 20. The heat transfer unit 30 of the present embodiment has a plurality of pipe bodies 31 forming the pipe line S3. The tubular body 31 of the present embodiment extends linearly along the Z axis. Each tube 31 is made of a material having excellent thermal conductivity. Specific constituent materials of the tubular body 31 include, for example, metal materials such as copper, aluminum, and alloys of any of these. The shapes or constituent materials of two or more of the plurality of pipes 31 may be the same or different from each other.

The plurality of pipe bodies 31 included in the heat transfer unit 30 are two pipe bodies 31_1, two pipe bodies 31_2, two pipe bodies 31_3, two pipe bodies 31_4, two pipe bodies 31_5, and two. It has a tube body 31_6, two tube bodies 31_7, and two tube bodies 31_8.

The two pipe bodies 31_1 connect the heat receiving portion 10 and the cylinder body 21_1. The two pipe bodies 31_2 connect the heat receiving portion 10 and the cylinder body 21_2. The two pipe bodies 31_3 connect the heat receiving portion 10 and the cylinder body 21_3. The two pipe bodies 31_4 connect the heat receiving portion 10 and the cylinder body 21_4. The two pipe bodies 31_5 connect the heat receiving portion 10 and the cylinder body 21_5. The two pipe bodies 31_6 connect the heat receiving portion 10 and the cylinder body 21_6. The two pipe bodies 31_7 connect the heat receiving portion 10 and the cylinder body 21_7. The two pipe bodies 31_8 connect the heat receiving portion 10 and the cylinder body 21_8.

A pipe line S3 is formed in each of the pipe bodies 31_1 to 31_8. Therefore, as shown in FIG. 3, the conduit S3 formed in the tubular body 31_1 communicates the accommodating chamber S1 and the condensing chamber S2_1. Similarly, the conduit S3 formed in the tubular body 31_2 to 31_8 communicates the accommodating chamber S1 and the condensing chamber S2_2 to S2_8.

As described above, the plurality of pipelines S3 communicate the accommodating chamber S1 with the plurality of condensing chambers S2. Here, in the accommodation chamber S1, a part of the refrigerant RE is vaporized by heat from a heating element (not shown). The refrigerant RE vaporized in the storage chamber S1 is supplied to the condensing chamber S2 corresponding to the pipe S3 at an appropriate timing for each pipe S3 via each pipe S3. In each condensing chamber S2, the refrigerant RE is condensed and liquefied from the gaseous state. In each pipeline S3, in addition to the gas of the refrigerant RE from the accommodating chamber S1, the liquid of the refrigerant RE from the condensing chamber S2 is present.

FIG. 4 is a diagram showing a liquid column RE and an air column REG of the refrigerant RE in the conduit S3 of the heat transfer unit 30. As shown in FIG. 4, in the pipeline S3, a liquid column REL composed of the liquid of the refrigerant RE and an air column REG composed of the gas of the refrigerant RE are formed. By forming the liquid column RE and the air column REG in the conduit S3 in this way, the pressure rise in the accommodation chamber S1 due to the vaporization of the refrigerant RE in the accommodation chamber S1 and the condensation liquefaction of the refrigerant RE in the condensation chamber S2 are caused. Due to the pressure drop, a pressure difference is generated between both ends of the conduit S3. Using this pressure difference as a driving force, self-excited vibration of the refrigerant RE can be generated.

Here, the width W of the conduit S3 (inner diameter of the tubular body 31) is preferably equal to or less than the Laplace length of the refrigerant RE so as to efficiently form the liquid column RE and the air column REG. This Laplace length is calculated by the following formula (1).
D = [σ / (g · (ρL-ρv))] ^ 0.5 (1)
In this equation (1), D is the Laplace length. σ is the surface tension of the refrigerant RE. g is the gravitational acceleration. ρL is the density when the refrigerant RE is a liquid. ρv is the density when the refrigerant RE is a gas.

As described above, a temperature difference is likely to occur in a plurality of condensing chambers S2 having different heat dissipation conditions or heat dissipation properties. Therefore, a pressure difference is likely to occur in the plurality of condensing chambers S2. Of the two condensing chambers S2 having this pressure difference, the conduit S3 connected to the condensing chamber S2 having the lower pressure has a liquid as compared with the conduit S3 connected to the condensing chamber S2 having the higher pressure. It is easy to move the column RL and the air column REG toward the condensing chamber S2. On the contrary, of the two condensing chambers S2 having this pressure difference, the conduit S3 connected to the condensing chamber S2 having the higher pressure is compared with the conduit S3 connected to the condensing chamber S2 having the lower pressure. Therefore, the liquid column RL and the air column REG can be easily moved toward the accommodation chamber S1. As described above, since the liquid column RE and the air column REG in each pipeline S3 can be easily moved, excellent cooling performance can be obtained.

As described above, the boiling cooler 1 described above has a heat receiving unit 10 that receives heat from a heating element (not shown), a heat radiating unit 20 that dissipates heat from the heat receiving unit 10, and heat from the heat receiving unit 10 to the heat radiating unit 20. It has a heat transfer unit 30 for transporting the heat transfer unit 30 and the heat transfer unit 30.

Here, the heat receiving unit 10 has a storage chamber S1 for storing the refrigerant RE. The heat radiating unit 20 has a condensing chamber S2_1 which is an example of the first condensing chamber and a condensing chamber S2_1 which is an example of the second condensing chamber. The heat dissipation conditions or heat dissipation properties of the condensing chambers S2_1 and S2_1 are different from each other. The heat radiating unit 20 dissipates heat from the heat receiving unit 10 by radiating heat from the refrigerant RE to the external fluid in the condensing chambers S2_1 and S2_1. The heat transfer unit 30 has two pipelines S3_1 which are examples of the plurality of first pipelines and two pipelines S3_1 which are examples of the plurality of second pipelines. The two pipelines S3_1 communicate the accommodating chamber S1 and the condensing chamber S2_1. The two pipelines S3_2 communicate the accommodating chamber S1 and the condensing chamber S2_2. The heat transfer unit 30 transfers heat from the heat receiving unit 10 to the heat radiating unit 20 by using the self-excited vibration of the refrigerant RE in the two pipelines S3_1 and the two pipelines S3_2.

In the above boiling cooler 1, the heat transfer unit 30 uses the self-excited vibration of the refrigerant RE to transfer heat from the heat receiving unit 10 to the heat radiating unit 20, so that even if the boiling cooler 1 is miniaturized, the refrigerant RE Can be smoothly circulated or moved. Therefore, as compared with the configuration adopting the salmon siphon method as described in Patent Document 1, excellent cooling capacity can be obtained even if the size is reduced. Further, by using self-excited vibration, the refrigerant RE can be circulated or moved regardless of the direction of gravity. Therefore, even when the boiling cooler 1 is installed in an automobile or the like with a change in the installation posture, excellent cooling performance can be obtained.

Moreover, since the heat dissipation conditions or heat dissipation properties of the condensing chambers S2_1 and S2_1 are different from each other, a temperature difference and a pressure difference are likely to occur between these condensing chambers. Therefore, the refrigerant RE can be easily moved by the self-excited vibration. As a result, the cooling capacity of the boiling cooler 1 can be stabilized.

Here, the width W of each pipeline S3 is preferably equal to or less than the Laplace length of the refrigerant RE, as described above. In this case, an air column and a liquid column of the refrigerant RE can be formed in the pipeline S3. As a result, the refrigerant RE can be efficiently moved or circulated in the pipeline S3.

In the present embodiment, the surface area of the outer shape of the condensing chamber S2_1 is larger than the surface area of the outer shape of the condensing chamber S2_1. Therefore, the heat dissipation properties of these condensing chambers S2_1 and S2_1 can be made different.

Further, the volume of the condensing chamber S2_1 is larger than the volume of the condensing chamber S2_1. Therefore, in the present embodiment, the heat dissipation properties of these condensing chambers S2_1 and S2_1 can be made different in this respect as well.

The heat radiating unit 20 of the present embodiment has eight condensing chambers S2 including the condensing chambers S2_1 and S2_2. Here, the heat radiating unit 20 has a condensing chamber S2_3, which is an example of the third condensing chamber. The heat dissipation conditions or heat dissipation of the condensing chamber S2_3 are different from those of the condensing chambers S2_1 and S2_2. The heat radiating unit 20 dissipates heat from the heat receiving unit 10 by radiating heat from the refrigerant RE to the external fluid in the condensing chamber S2_3. The heat transfer unit 30 has two pipelines S3_3, which is an example of a plurality of third pipelines. The two pipelines S3_3 communicate the accommodating chamber S1 and the condensing chamber S2_3. The heat radiating unit 20 transports heat from the heat receiving unit 10 to the heat radiating unit 20 by using the self-excited vibration of the refrigerant RE in the two pipelines S3_3. As described above, since the heat dissipation conditions or heat dissipation properties of the condensing chambers S2_1, S2_2, and S2_3 are different from each other, the refrigerant RE in the pipelines S3_1, S3_2, and S3_3 can be easily moved by self-excited vibration. As a result, the cooling capacity of the boiling cooler 1 can be stabilized.

Of the plurality of condensing chambers S2-1 to S2_8 included in the heat radiating unit 20, any one condensing chamber S2 may be regarded as the first condensing chamber. In this case, of the other two condensing chambers S2 different from the arbitrary one condensing chamber S2, one may be regarded as the second condensing chamber and the other as the third condensing chamber. Further, the first conduit, the second conduit and the third conduit are selected from the eight sets of conduits S3 corresponding to the first condensing chamber, the second condensing chamber and the third condensing chamber.

2. Second Embodiment Hereinafter, the second embodiment of the present invention will be described. For the elements whose actions and functions are the same as those of the first embodiment in the embodiments illustrated below, the reference numerals used in the description of the first embodiment will be diverted and detailed description of each will be omitted as appropriate.

FIG. 5 is a plan view of the boiling cooler 1A according to the second embodiment. FIG. 6 is a cross-sectional view taken along the line BB in FIG. The boiling cooler 1A is the same as the boiling cooler 1 of the first embodiment described above, except that the boiling cooler 1A has a heat radiating section 20A instead of the heat radiating section 20. The heat radiating unit 20A is the same as the heat radiating unit 20 described above, except that the heat radiating side tube 23 is further provided.

However, in the examples shown in FIGS. 5 and 6, the plurality of condensing chambers S2 or the plurality of cylinders 21 have the same shape and size. In the present embodiment, even with such a plurality of condensing chambers S2 or a plurality of cylinders 21, the heat dissipation conditions of the plurality of condensing chambers S2 can be different. The plurality of condensing chambers S2 may have the same configuration as that of the first embodiment described above.

As shown in FIG. 5, the heat radiating side tube 23 is arranged on the heat radiating fins 22. In the example shown in FIG. 5, the heat radiating side tube 23 is arranged on the heat radiating fin 22 located at the position farthest from the heat receiving unit 10 among the plurality of heat radiating fins 22 included in the heat radiating unit 20A. The arrangement of the heat radiating side tube 23 is not limited to the example shown in FIG. For example, the heat radiating side tube 23 may be arranged between any two adjacent heat radiating fins 22 among the plurality of heat radiating fins 22.

The heat radiating side tube 23 has a closed loop shape, that is, an endless tube. In the example shown in FIG. 5, the heat radiating side tube 23 is connected to a plurality of cylinders 21 of the cylinders 21_1 to 21_8 included in the heat radiating unit 20A, excluding the cylinders 21_4. Here, the heat radiating side tube 23 may only come into contact with the cylinder 21, or may be joined to the cylinder 21 with a brazing material or the like. Further, the heat radiating side tube 23 may be joined to the heat radiating fin 22 with an adhesive, a brazing material, or the like.

The heat radiating side tube 23 may be connected to at least one of the tubes 21_1 to 21_8, and may be connected to, for example, one tube 21 or all the tubes 21. May be connected to. Further, the area where the heat radiating side tube 23 and the plurality of cylinders 21 are connected may be the same or different from each other.

A pipe line S4 through which the refrigerant REX flows is formed in the heat radiating side pipe body 23. The pipeline S4 is a closed loop shape, that is, an endless space in which self-excited vibration of the refrigerant REX is generated by heat from the tubular body 21. Therefore, the width of the conduit S4 is preferably equal to or less than the Laplace length of the refrigerant REX, like the width W of the conduit S3 described above. As the refrigerant REX, the same refrigerant as the above-mentioned refrigerant RE can be used.

FIG. 7 is a diagram for explaining the operation of the heat radiating side tube 23. In FIG. 7, the heat dissipation side tube 23 and the two condensing chambers S2_1 and S2_2 are typically illustrated. In the heat radiating side tube 23, a plurality of liquid columns REXL and a plurality of air columns REXG of the refrigerant REX are formed. The plurality of liquid columns REXL and the plurality of air columns REXG tend to be spaced or length different from each other. Here, the air column REXG has a lower thermal conductivity than the liquid column REXL. Therefore, the heat dissipation conditions of the condensing chambers S2_1 and S2_2 can be different.

As described above, the heat radiating unit 20A has a heat radiating side tube 23 that forms a space for accommodating the refrigerant REX as a space that does not communicate with the condensing chambers S2_1 and S2_2. The heat radiating side tube 23 is thermally connected to the condensing chambers S2_1 and S2_2, and the refrigerant REX is self-excited and vibrated by the heat from the condensing chambers S2_1 and S2_2. Therefore, the heat dissipation conditions of these condensing chambers S2_1 and S2_1 can be different.

Here, since the heat radiating side tube 23 forms a closed loop shape, the refrigerant REX in the heat radiating side tube 23 can be circulated by self-excited vibration.

Further, the boiling point of the refrigerant REX contained in the heat radiation side tube 23 is preferably lower than the boiling point of the refrigerant RE housed in the storage chamber S1. In this case, as compared with the case where the boiling point of the refrigerant REX contained in the heat radiating side tube 23 is equal to or higher than the boiling point of the refrigerant RE housed in the storage chamber S1, the heat radiating side tube 23 is affected by heat from the condensing chamber S2. It is possible to easily generate self-excited vibration of the refrigerant REX.

The same effect as that of the above-mentioned first embodiment can be obtained also by the above-mentioned second embodiment.

3. 3. Third Embodiment Hereinafter, the third embodiment of the present invention will be described. For the elements whose actions and functions are the same as those of the first embodiment in the embodiments illustrated below, the reference numerals used in the description of the first embodiment will be diverted and detailed description of each will be omitted as appropriate.

FIG. 8 is a cross-sectional view of the boiling cooler 1B according to the third embodiment. The boiling cooler 1B is the same as the boiling cooler 1 of the first embodiment described above, except that the boiling cooler 1B has a heat radiating section 20B instead of the heat radiating section 20. The heat radiating unit 20B is the same as the heat radiating unit 20 described above, except that a part of the plurality of heat radiating fins 22 is the heat radiating fins 22a and 22b.

However, in the examples shown in FIGS. 5 and 6, as in the second embodiment described above, the plurality of condensing chambers S2 or the plurality of cylinders 21 have the same shape and size. In the present embodiment, even with such a plurality of condensing chambers S2 or a plurality of cylinders 21, the heat dissipation conditions of the plurality of condensing chambers S2 can be different. The plurality of condensing chambers S2 may have the same configuration as that of the first embodiment described above.

Similar to the first embodiment described above, each heat radiation fin 22 is connected to each of the condensing chambers S2_1, S2_2 and S2_3. On the other hand, the heat radiation fins 22a are connected to the condensing chamber S2_3 without being connected to the condensing chambers S2_1 and S2_2. The heat radiating fins 22b are connected to the condensing chambers S2_2 and S2_3, respectively, without being connected to the condensing chamber S2_1.

The arrangement, number, size, etc. of the heat radiation fins 22a and 22b are not limited to the example shown in FIG. 8, and are arbitrary. For example, the sizes of the heat radiating fins 22a and 22b may be the same as those of the heat radiating fins 22. In this case, a gap may be appropriately provided between the heat radiation fins 22a and 22b and the condensing chambers S2_1 and S2_2.

As described above, the heat radiating unit 20B has a plurality of heat radiating fins 22, 22a and 22b. The thermal resistance between the plurality of heat radiation fins 22, 22a and 22b and the condensing chamber S2_1 is smaller than the thermal resistance between the plurality of heat radiation fins 22, 22a and 22b and the condensing chamber S2_1. Therefore, the heat dissipation conditions of these condensing chambers S2_1 and S2_1 can be different.

The same effect as that of the above-mentioned first embodiment can be obtained also by the above-mentioned third embodiment.

4. Modification Examples Each of the above-exemplified forms can be variously transformed. Specific modifications that can be applied to each of the above-described forms are illustrated below. Two or more embodiments arbitrarily selected from the following examples can be appropriately merged to the extent that they do not contradict each other.

In the above-described embodiment, the configuration in which the plurality of condensing chambers S2 of the heat radiating unit 20 have the same planological shape is exemplified, but the present invention is not limited to this example. Of the plurality of condensing chambers S2 included in the heat radiating unit 20, two or more condensing chambers S2 may have different planar shapes.

Further, in the above-described embodiment, the configuration in which the number of the condensing chambers S2 included in the heat radiating unit 20 is eight is exemplified, but the number is not limited to eight, and the number is not limited to eight and is two or more and seven or less or nine or more. It may be.

Further, in the above-described embodiment, a configuration in which the shape of the condensing chamber S2 in a plan view is circular is exemplified, but the present invention is not limited to this example. For example, the plan view shape of the condensing chamber S2 may be another polygon such as a triangle, a quadrangle, a pentagon or a hexagon, or an ellipse or the like.

Further, in the above-described embodiment, the arrangement of the condensing chamber S2 in a plan view is exemplified by a staggered arrangement, but the arrangement is not limited to this example. For example, the arrangement of the condensing chamber S2 in a plan view may be another regular arrangement such as a matrix arrangement, or an irregular arrangement.

Further, in the above-described embodiment, a configuration in which the shapes of the plurality of conduits S3 or the plurality of tubular bodies 31 of the heat transfer unit 30 are the same as each other is exemplified, but the embodiment is not limited to this example. The shapes of two or more of the plurality of conduits S3 or the plurality of tubular bodies 31 included in the heat transfer unit 30 may be different from each other. Further, the lengths or widths of two or more of the plurality of conduits S3 or the plurality of tubular bodies 31 included in the heat transfer unit 30 may be different from each other.

Further, in the above-described embodiment, the configuration in which the number of pipelines S3 connected to one condensing chamber S2 is two is exemplified, but the configuration is not limited to this example, and the number may be three or more.

In the above-described embodiment, the configuration in which the conduit S3 is provided in the tubular body 31 is exemplified, but the present invention is not limited to this example. For example, the pipeline S3 may be provided on a plate-shaped or block-shaped member. Further, a plurality of pipelines S3 may be provided in one member.

1 ... boiling cooler, 1A ... boiling cooler, 1B ... boiling cooler, 10 ... heat receiving part, 20 ... heat dissipation part, 20A ... heat dissipation part, 20B ... heat dissipation part, 22 ... heat dissipation fin, 22a ... heat dissipation fin, 22b ... Heat dissipation fins, 23 ... heat dissipation side tube, 30 ... heat transfer part, RE ... refrigerant, REX ... refrigerant, S1 ... storage chamber, S2 ... condensing chamber, S2_1 ... condensing chamber, S2_2 ... condensing chamber, S2_3 ... condensing chamber, S2_4 ... Condensing chamber, S2_5 ... Condensing chamber, S2_6 ... Condensing chamber, S2_7 ... Condensing chamber, S2_8 ... Condensing chamber, S3 ... Pipeline, S3_1 ... Pipeline, S3_2 ... Pipeline, S3_3 ... Pipeline, S3_4 ... Pipeline, S3_5 ... Pipeline, S3_6 ... Pipeline, S3_7 ... Pipeline, S3_8 ... Pipeline, S4 ... Pipeline.

Claims (9)

A heat receiving part that has a storage chamber for storing the refrigerant and receives heat from the heating element,
It has a first condensing chamber and a second condensing chamber having different heat radiating conditions or heat radiating properties from each other, and radiates heat from the heat receiving portion by radiating heat from the refrigerant to the external fluid in the first condensing chamber and the second condensing chamber. The heat dissipation part and
It has a plurality of first pipelines communicating the accommodation chamber and the first condensation chamber, and a plurality of second pipelines communicating the accommodation chamber and the second condensation chamber, and the plurality of first pipelines. It has a heat transfer part that transports heat from the heat receiving part to the heat radiating part by using the self-excited vibration of the refrigerant in the pipeline and the plurality of second pipelines.
Boiling cooler. The surface area of the outer shape of the first condensation chamber is larger than the surface area of the outer shape of the second condensation chamber.
The boiling cooler according to claim 1. The volume of the first condensing chamber is larger than the volume of the second condensing chamber.
The boiling cooler according to claim 1 or 2. The heat radiating portion further has a plurality of heat radiating fins.
The thermal resistance between the plurality of heat radiation fins and the first condensation chamber is smaller than the thermal resistance between the plurality of heat radiation fins and the second condensation chamber.
The boiling cooler according to any one of claims 1 to 3. The heat radiating unit has a heat radiating side tube connected to the first condensing chamber and the second condensing chamber.
The heat radiation side tube body forms a space for accommodating a refrigerant self-excited and vibrated by heat from the first condensing chamber and the second condensing chamber as a space that does not communicate with the first condensing chamber and the second condensing chamber. ,
The boiling cooler according to any one of claims 1 to 4. The boiling point of the refrigerant contained in the heat-dissipating side tube is lower than the boiling point of the refrigerant contained in the storage chamber.
The boiling cooler according to claim 5. The heat dissipation side tube has a closed loop shape.
The boiling cooler according to claim 5 or 6. The heat radiating unit has a third condensing chamber having different heat radiating conditions or heat radiating properties from the first condensing chamber and the second condensing chamber, and the refrigerant is condensed and liquefied from the gaseous state in the third condensing chamber. The heat from the heat receiving part is dissipated to dissipate the heat.
The heat transfer unit has a plurality of third pipelines that communicate the storage chamber and the third condensation chamber, and the heat receiving unit uses the self-excited vibration of the refrigerant in the plurality of third pipelines to obtain the heat transfer unit. Transport heat to the heat dissipation part,
The boiling cooler according to any one of claims 1 to 7. The width of each of the plurality of first pipelines and the plurality of second pipelines is equal to or less than the Laplace length of the refrigerant contained in the storage chamber.
The boiling cooler according to any one of claims 1 to 8.

Images