JP7835007B2 - cooling device - Google Patents

Description

This disclosure relates to a cooling device.

Cooling devices are known for cooling heat-generating elements such as electronic components.

The cooling device described in Patent Document 1 comprises a cooling plate in contact with multiple electronic components and a housing containing a cooling medium. Multiple cooling fins are formed on the surface of the cooling plate opposite to the surface in contact with the electronic components. Furthermore, a trapezoidal columnar base is provided on the bottom surface of the housing, overlapping with the multiple fins in a plan view.

The cooling device comprises a cooling channel for cooling electronic components, an introduction channel for introducing a cooling medium from an inlet, and an outlet channel for discharging the cooling medium to an outlet. The cooling channel is provided with multiple fins and land sections. The introduction channel and the outlet channel are located on either side of the cooling channel.

In this cooling system, the flow path area of the introduction channel is varied in the longitudinal direction to ensure uniformity in the supply of the cooling medium into the cooling channel.

Japanese Patent Publication No. 2012-174963

However, in conventional cooling systems, the refrigerant travels linearly along the longitudinal direction of the inlet channel before flowing into the cooling channel towards the outlet. Therefore, the cooling medium is particularly difficult to distribute near the inlet of the cooling channel. As a result, an uneven distribution of flow velocity occurs in the cooling channel. Consequently, variations in cooling performance occur within the cooling surface.

To solve the above problems, a cooling device according to a preferred embodiment of the present disclosure includes a housing that includes a first base having a cooling surface for cooling a heat-generating element and a surface opposite to the cooling surface, and a second base spaced apart from the first base and facing the opposite surface; a plurality of cooling fins disposed within the housing and protruding from the first base toward the second base; an introduction pipe connected to the housing and having an introduction passage for introducing a refrigerant into the housing; and an outlet passage connected to the housing and having an outlet passage for discharging the refrigerant from inside the housing. The housing comprises an outlet pipe and a flow straightening section for straightening the refrigerant within the housing. The housing is divided into a refrigerant inlet passage connected to the inlet passage, a refrigerant outlet passage connected to the outlet passage, and a cooling passage located between the refrigerant inlet passage and the refrigerant outlet passage in a plan view, where the plurality of fins are arranged. The second base has a plate-shaped substrate and a convex portion projecting from the substrate toward the first base, overlapping with the plurality of fins in a plan view. The flow straightening section is positioned in the refrigerant inlet passage of the housing.

This is a perspective view showing the cooling device of the first embodiment. Figure 1 is a plan view of the cooling device shown. Figure 1 is a cross-sectional view of the cooling device shown. Figure 2 is an enlarged view of the rectifier section. Figure 3 is an enlarged view of the rectifier section. This diagram shows the flow of refrigerant within a conventional cooling system. This figure shows the flow of refrigerant within the cooling device shown in Figure 2. This diagram shows the rectifier section of the first modified example. This diagram shows the rectifier section of the second modified example. This diagram shows the rectifier section of the third modified example. This diagram shows the rectifier section of the fourth modified example. This figure shows another example of the outlet pipe arrangement shown in Figure 2. This figure shows another example of the outlet pipe arrangement shown in Figure 2. This is a perspective view showing a cooling device according to the second embodiment. Figure 14 is a plan view of the cooling device shown. Figure 14 is a cross-sectional view of the cooling device shown. Figure 15 is an enlarged view of the rectifying section. This figure shows the flow of refrigerant within the cooling device shown in Figure 15. This diagram shows the rectifier section of the fifth modified example. This diagram shows the rectifier section of the sixth modified example. This is a perspective view showing a cooling device according to the third embodiment. Figure 21 is a plan view of the cooling device shown. Figure 21 is a cross-sectional view of the cooling device shown. This figure shows the flow of refrigerant within the cooling device shown in Figure 21. This diagram shows the rectifier section of the seventh modified example. This is a perspective view showing the cooling device of the eighth modified example. Figure 26 is a plan view of the cooling device shown. Figure 26 is a cross-sectional view of the cooling device shown.

The following describes preferred embodiments of this disclosure with reference to the attached drawings. Note that the dimensions and scale of parts in the drawings differ from actual dimensions as appropriate, and some parts are shown schematically for ease of understanding. Furthermore, the scope of this disclosure is not limited to these embodiments unless otherwise stated in the following description.

1. First Embodiment 1-1. Overview of Cooling Device 1 Figure 1 is a perspective view showing the cooling device 1 of the first embodiment. Figure 2 is a plan view of the cooling device 1 shown in Figure 1. Figure 3 is a cross-sectional view of the cooling device 1 shown in Figure 1. For convenience, the following explanation will use mutually orthogonal X, Y, and Z axes as appropriate. In the following, one direction along the X axis is the X1 direction, and the direction opposite to the X1 direction is the X2 direction. One direction along the Y axis is the Y1 direction, and the direction opposite to the Y1 direction is the Y2 direction. One direction along the Z axis is the Z1 direction, and the direction opposite to the Z1 direction is the Z2 direction. In addition, the plane along the X and Y axes will be called the X-Y plane. In the following, the Z1 direction will be called "upwards", and the Z2 direction will be called "downwards". In the following, viewing from the Z1 direction or the Z2 direction will be called a "plan view".

The cooling device 1 shown in Figure 1 is a device for cooling the heat-generating element 100. The heat-generating element 100 is, for example, a power semiconductor element such as a diode, a power MOSFET (metal-oxide-semiconductor field-effect transistor), an IGBT (Insulated Gate Bipolar Transistor), and a thymistor. These power semiconductor elements are used in power electronics products such as inverters and rectifiers used in railway vehicles, automobiles, and household electrical appliances.

As shown in Figures 1, 2, and 3, the cooling device 1 comprises a housing 2, a plurality of cooling fins 3, an inlet pipe 4, an outlet pipe 5, and a flow straightening section 6. As shown in Figure 1, the plurality of fins 3 are arranged inside the housing 2. A heat-generating element 100 is positioned on the outer surface of the housing 2. Liquid refrigerant is contained within the housing 2. This cooling device 1 cools the heat-generating element 100 by dissipating heat through the convection heat transfer effect of the refrigerant flowing between the plurality of fins 3.

The refrigerant is not particularly limited, but examples include aqueous refrigerants such as water, alcohol refrigerants such as methanol, ketone refrigerants such as acetone, glycol refrigerants such as ethylene glycol, carbon fluoride refrigerants such as Fluorinert, fluorocarbon refrigerants such as HFC134a, low GWP refrigerants such as HFO-1234yf, ether refrigerants, and hydrocarbon refrigerants such as butane. Surfactants such as fluorine-based surfactants, silicone-based surfactants, or hydrocarbon-based surfactants may be added to the refrigerant as needed. Furthermore, two or more of the aforementioned refrigerants may be combined.

1-2. Enclosure 2
The housing 2 shown in Figure 1 is a container having an internal space for housing a refrigerant. As shown in Figure 2, the shape of the housing 2 in plan view is rectangular. The X1 and X2 directions coincide with the longitudinal direction of the housing 2, and the Y1 and Y2 directions coincide with the short direction of the housing 2. Furthermore, the shape in plan view does not have to be rectangular; for example, it may be a quadrilateral such as a square, trapezoid, or parallelogram, or any other polygon.

The housing 2 shown in Figures 1, 2, and 3 has a first base portion 21, a second base portion 22, and a side wall portion 23. Note that the first base portion 21 is omitted from the illustration in Figure 2.

The first base portion 21 is a flat plate-shaped member aligned with the X-Y plane. The second base portion 22 and the side wall portion 23 are integrally formed in the illustrated example and have a recess. The first base portion 21 is positioned on the side wall portion 23 so as to close the opening of the recess. The second base portion 22 is a portion aligned with the X-Y plane and is spaced apart from the first base portion 21. The side wall portion 23 is a frame-shaped portion extending from the second base portion 22 in the Z1 direction.

Furthermore, the direction in which the second base portion 22 and the first base portion 21 overlap coincides with the Z1 direction. Also, in the illustrated example, the second base portion 22 and the side wall portion 23 are integrally formed, but they may be separate components. Similarly, the first base portion 21 and the side wall portion are separate components, but they may be integrally formed.

As shown in Figure 1, the first base portion 21 has a cooling surface 201 and a surface 202 opposite to the cooling surface 201. The cooling surface 201 is thermally connected to the heat-generating element 100 and is the surface that cools the heat-generating element 100. Furthermore, as shown in Figures 1 and 3, the surface 202 opposite to the cooling surface 201 is connected to a plurality of fins 3 and a rectifier portion 6, respectively.

"Thermal connection" means satisfying any of the following conditions a, b, or c: Condition a: The two members are in direct physical contact. Condition b: The two members are placed with a gap of 50 μm or less between them. Condition c: The two members are physically connected via another member with a thermal conductivity of 10 W· ^m⁻¹ · ^K⁻¹ or higher. In each of the conditions, thermal grease and adhesives may be present between the two members. In this case, the adhesive preferably contains a thermally conductive filler or the like from the viewpoint of enhancing thermal conductivity.

As shown in Figure 1, the second base portion 22 faces the surface 202 opposite to the cooling surface 201. The second base portion 22 has a substrate 221 and a protrusion 222. The substrate 221 is a flat plate-like portion along the X-Y plane. The protrusion 222 is a portion that projects from the substrate 221 in the Z1 direction. As shown in Figure 2, the protrusion 222 is located in the center of the substrate 221 in the Y1 direction. The protrusion 222 is provided across the entire longitudinal direction of the substrate 221. In the illustrated example, the shape of the protrusion 222 in plan view is a rectangle along the longitudinal direction of the housing 2. Note that the shape of the protrusion 222 in plan view is not limited to the illustrated example and is arbitrary. Furthermore, an outlet pipe 5 is connected to the second base portion 22. Specifically, the outlet pipe 5 is connected to the portion of the substrate 221 where the protrusion 222 is not provided.

The side wall portion 23 shown in Figure 1 is located between the first base portion 21 and the second base portion 22, and connects the first base portion 21 and the second base portion 22. As shown in Figure 2, the side wall portion 23 has a first side portion 231, a second side portion 232, a third side portion 233, and a fourth side portion 234. In the illustrated example, these side portions are integrally formed. The first side portion 231 and the second side portion 232 are portions along the longitudinal direction of the housing 2. The second side portion 232 is spaced apart from the first side portion 231 and is located in the Y2 direction relative to the first side portion 231. The third side portion 233 and the fourth side portion 234 are portions along the short direction of the housing 2. The fourth side portion 234 is spaced apart from the third side portion 233 and is located in the X1 direction relative to the third side portion 233. Furthermore, the third side portion 233 and the fourth side portion 234 are located between the first side portion 231 and the second side portion 232, and connect them. The inlet pipe 4 is connected to the third side portion 233.

As shown in Figure 2, the inside of the housing 2 is divided into a refrigerant inlet channel C1, a refrigerant outlet channel C2, and a cooling channel C3. In a plan view, the cooling channel C3 is located between the refrigerant inlet channel C1 and the refrigerant outlet channel C2. The cooling channel C3 is the region where the protrusion 222 exists.

The housing 2 is formed from a material with excellent thermal conductivity. Specific materials for the housing 2 include, for example, metals such as copper, aluminum, or alloys thereof.

1-3. Multiple fins 3
As shown in Figure 3, each of the multiple fins 3 is connected to the first base 21 of the housing 2. In the illustrated example, each fin 3 is a pin fin. The multiple fins 3 are spaced apart from each other. Each fin 3 has a cylindrical shape that extends downward from the first base 21. However, the shape of each fin 3 is not limited to a cylindrical shape. For example, each fin 3 may be a prismatic shape or a cone shape with a pointed tip. Also, each fin 3 is not limited to a pin fin; for example, it may be a corrugated fin.

As shown in Figure 2, the multiple fins 3 are located in the center of the first base 21 in the Y1 direction and are arranged in the longitudinal direction of the housing 2. In a plan view, the multiple fins 3 overlap the protrusions 222 of the second base 22. Therefore, the aforementioned cooling channel C3 can also be said to be the region where the multiple fins 3 exist. Furthermore, in a plan view, the refrigerant introduction channel C1 and the refrigerant discharge channel C2 exist on either side of the multiple fins 3. Also, as shown in Figure 3, each fin 3 does not contact the protrusions 222 of the second base 22, but it may contact the protrusions 222.

Each fin 3 is formed from a material with excellent thermal conductivity. Each fin 3 is formed from, for example, the same material as the housing 2. Specific constituent materials for each fin 3 include, for example, metals such as copper, aluminum, or alloys thereof.

1-4.Introduction pipe 4
As shown in Figure 2, the introduction pipe 4 is a pipe extending in the X2 direction from the third side portion 233. Also as shown in Figure 2, the introduction pipe 4 has an introduction passage E4 for introducing refrigerant into the housing 2. The introduction passage E4 is connected to the refrigerant introduction passage C1. The introduction pipe 4 has an inlet E40, which is the connection point to the refrigerant introduction passage C1. In the illustrated example, the inner wall surface 40 of the introduction pipe 4 that forms the introduction passage E4 is cylindrical. The central axis A4 of the introduction passage E4 coincides with the X axis.

Specific materials for the inlet pipe 4 include, for example, metals such as copper, aluminum, or alloys thereof.

1-5. Outlet pipe 5
As shown in Figure 1, the outlet pipe 5 is a pipe extending from the substrate 221 in the Z2 direction. Also, as shown in Figure 2, the outlet pipe 5 has an outlet passage E5 for discharging refrigerant from inside the housing 2. The outlet passage E5 is connected to the refrigerant outlet passage C2. The outlet pipe 5 has an outlet E50, which is the connection point to the refrigerant outlet passage C2. In the illustrated example, the inner wall surface 50 of the outlet pipe 5 that forms the outlet passage E5 is cylindrical. The central axis A5 of the outlet passage E5 coincides with the Z axis. The outlet pipe 5 is also positioned diagonally to the inlet pipe 4.

Specific materials for the outlet tube 5 include, for example, metals such as copper, aluminum, or alloys of any of these.

1-6. Rectifier section 6
The rectifier 6 shown in Figure 1 rectifies the flow of refrigerant within the housing 2 by adjusting the direction of flow of the refrigerant introduced from the introduction pipe 4. Specifically, the rectifier 6 is provided to make the flow of refrigerant in the cooling channel C3 more uniform. In this embodiment, the rectifier 6 has a plurality of protrusions 60.

As shown in Figure 2, each projection 60 is positioned in the refrigerant introduction channel C1 of the housing 2. Specifically, as shown in Figure 3, the projections 60 are positioned on the surface 202 of the first base 21 opposite to the cooling surface 201. Each projection 60 protrudes from the first base 21 toward the second base 22. A portion of this opposite surface 202 forms part of the wall surface of the refrigerant introduction channel C1. Furthermore, each projection 60 is positioned near the inlet E40 of the introduction pipe 4. In other words, as shown in Figure 2, each projection 60 is positioned closer to the inlet E40 than the center line A0 along the Y-axis of the housing 2.

Figure 4 is an enlarged view of the rectifier 6 shown in Figure 2. Figure 5 is an enlarged view of the rectifier 6 shown in Figure 3. As shown in Figure 4, the multiple protrusions 60 are spaced apart from each other and arranged in a line along the central axis A4 of the inlet passage E4. For example, the multiple protrusions 60 may be arranged from the inlet E40 toward the outlet E50. Alternatively, the multiple protrusions 60 may not be arranged in a line but randomly.

A portion of each projection 60 is located within a virtual space V40 surrounded by a virtual extension surface V4 of the inner wall surface 40 of the inlet pipe 4. The virtual extension surface V4 is a surface that is virtually extended from the inner wall surface 40. In this embodiment, since the inner wall surface 40 is aligned in the X1 direction, the virtual extension surface V4 is a surface that is virtually extended from the inner wall surface 40 in the X1 direction. Furthermore, since the inner wall surface 40 is cylindrical, the virtual extension surface V4 is also cylindrical.

As shown in Figure 4, the shape of each projection 60 in plan view is elliptical. Therefore, the contour of each projection 60 in plan view includes a curve. Furthermore, the planar area of each projection 60 is larger than the planar area of each of the multiple fins 3. Also, as shown in Figure 4, the minor axis of each projection 60 is perpendicular to the central axis A4 of the inlet passage E4. The major axis of each projection 60 is parallel to the central axis A4. The width D62 of each projection 60 in the minor axis direction is smaller than the width D4, i.e., the diameter, of the inlet E40 of the inlet pipe 4. The width D61 of each projection 60 in the major axis direction is larger than the width D4. Furthermore, as shown in Figure 5, the height T6 of each projection 60 in the rectifier section 6 is smaller than the height T3 of each fin 3.

Furthermore, as shown in Figures 4 and 5, each projection 60 has a side surface 61 and an end surface 62. The side surface 61 is a surface aligned with the Z1 direction. Since the shape of each projection 60 in plan view is elliptical, the side surface 61 includes a curved surface. The side surface 61 is curved both in the portion facing the multiple fins 3 and in the portion facing away from the multiple fins 3. The end surface 62 is a surface aligned with the X-Y plane. In the illustrated example, the edge of the end surface 62 is rounded and curved. Therefore, as shown in Figure 5, each projection 60 includes a curved portion when viewed from the direction in which the refrigerant introduction channel C1 and the cooling channel C3 overlap.

As mentioned above, the surface area of each projection 60 is larger than the surface area of each fin 3. Furthermore, the side surface 61 of each projection 60 has a curved surface. As shown in Figure 4, a portion of the curved side surface 61 is located inside the virtual space V40. Therefore, due to the Coanda effect on the curved surface of each projection 60, the direction of the refrigerant, which would normally travel in a straight line in the X1 direction, can be changed to the Y1 direction immediately after entering from the inlet E40. Specifically, the refrigerant travels along the side surface 61 as shown by arrow a10 in Figure 4. As a result, the refrigerant immediately after entering from the inlet E40 can be guided towards the multiple fins 3.

This cooling device 1 can suppress uneven flow of the refrigerant within the housing 2. In particular, it can suppress uneven flow of the refrigerant in the cooling channel C3.

Figure 6 shows the flow of refrigerant in a conventional cooling device 1X. When the inlet pipe 4 is positioned at the third side section 233 and the outlet pipe 5 is positioned diagonally opposite the inlet pipe 4, the refrigerant flows in a straight line in the X1 direction and spreads in the Y1 direction. Therefore, in the conventional cooling device 1X shown in Figure 6, the refrigerant flows in the direction indicated by arrow a5 in Figure 6. As a result, the refrigerant has difficulty reaching the regions S1a and S1b, indicated by the dot pattern in Figure 6, among the regions where multiple fins 3 are provided. This results in a bias in the flow velocity distribution in the cooling channel C3 where multiple fins 3 are provided. In particular, immediately after inflow from the inlet E40, the refrigerant flow velocity is fastest, and the spread of the refrigerant in the Y1 direction is smallest. Therefore, the refrigerant flow rate in region S1a near the inlet E40 is most likely to decrease. Region S1a is the region near the inlet E40 of the inlet pipe 4. Region S1b is the region near the outlet E50 of the outlet pipe 5.

As a result of uneven refrigerant flow in the cooling channel C3, variations occur in the cooling performance of the heat-generating element 100 on the cooling surface 201. In areas of the cooling surface 201 corresponding to areas where the refrigerant flow is concentrated, the heat-generating element 100 can be efficiently cooled due to enhanced heat transfer by convection. Conversely, in areas of the cooling surface 201 corresponding to areas with less refrigerant flow, heat transfer is not enhanced, resulting in reduced cooling efficiency.

Figure 7 shows the flow of refrigerant within the cooling device 1 shown in Figure 2. As described above, the cooling device 1 has a protrusion 222 on its second base portion 22. With the configuration having the protrusion 222, the flow path area in the cooling channel C3 is narrower compared to the configuration without the protrusion 222. Therefore, the flow velocity of the refrigerant increases, and thus the cooling efficiency in the cooling channel C3 can be improved. Thus, the cooling efficiency of the cooling surface 201 can be improved. Furthermore, with the presence of the protrusion 222, the refrigerant can more easily travel in the X1 direction along the protrusion 222 and the second side portion 232 compared to the case without the protrusion 222. Therefore, the refrigerant introduced from the introduction pipe 4 can easily travel as shown by arrow a1 in Figure 7. As a result, difficulty in refrigerant reaching region S1b is suppressed.

Furthermore, the cooling device 1 has a flow straightening section 6 positioned in the refrigerant introduction channel C1. By having this flow straightening section 6, as described above, the Coanda effect of the side surface 61 allows the inflow direction of the refrigerant flowing from the introduction pipe 4 in the X1 direction to be changed to the Y1 direction. Therefore, a portion of the refrigerant immediately after flowing in from the introduction pipe 4 moves as shown by arrow a2 in Figure 7. As a result, the difficulty in refrigerant spreading to region S1a in Figure 6 is suppressed, and the refrigerant immediately after flowing in from the introduction pipe 4 can be guided towards the multiple fins 3.

Furthermore, due to the action of the protrusion 222, which facilitates the refrigerant's movement in the X1 direction, and the action of the rectifier 6, which changes the direction of the refrigerant to the Y1 direction, the refrigerant moves through the cooling channel C3 as shown by arrow a3. Therefore, the refrigerant can be distributed throughout the entire cooling channel C3. Then, in the refrigerant outlet channel C2, the refrigerant moves towards the outlet E50 as shown by arrow a4.

As described above, the presence of the protrusion 222 and the rectifier 6 allows the refrigerant to diffuse throughout the entire cooling channel C3, thereby suppressing uneven flow in the cooling channel C3. Therefore, uniformity of the refrigerant in the cooling channel C3 can be achieved, reducing variations in cooling performance within the cooling surface 201. Consequently, the cooling performance of the cooling device 1 is improved. This also reduces variations in temperature differences within the heating element 100 that contacts the cooling surface 201. For example, if the heating element 100 includes multiple semiconductor elements, the temperature difference between these semiconductor elements is suppressed. Therefore, sufficient output from each semiconductor element can be ensured.

Furthermore, as mentioned above, the inlet pipe 4 is connected to the third side portion 233. Therefore, compared to, for example, the case where the inlet pipe 4 is connected to the substrate 221, the refrigerant is more likely to travel in the X1 direction immediately after flowing in from the inlet pipe 4. For this reason, in the case of the cooling device 1 where the inlet pipe 4 is connected to the third side portion 233, the effect of providing the rectifier 6 is particularly easily demonstrated.

Furthermore, as shown in Figure 4, the center C6 of each projection 60 in a plan view is located closer to the multiple fins 3 than to the virtual space V40. Therefore, compared to the case where the center C6 is located inside the virtual space V40, the Coanda effect can increase the flow rate of the refrigerant guided to the multiple fins 3.

Furthermore, as shown in Figure 4, the point 65 closest to the inlet E40 in the plan view contour of each projection 60 is located closer to the multiple fins 3 than to the virtual space V40. Point 65 is also the upstream portion of the refrigerant flow. Because point 65 is located closer to the multiple fins 3 than to the virtual space V40, the Coanda effect can increase the flow rate of the refrigerant guided to the multiple fins 3 compared to when point 65 is located within the virtual space V40.

Each projection 60 is located closer to the multiple fins 3 than the central axis A4 of the introduction passage E4. Furthermore, each projection 60 is positioned between the central axis A4 and the multiple fins 3 in a plan view. Therefore, compared to a scenario where some of the projections 60 are located below the central axis A4 in Figure 4, this configuration allows for a significant reduction in the flow rate of the refrigerant flowing in the X1 direction while increasing the flow rate of the refrigerant guided by the multiple fins 3.

The maximum length (width D62) of each projection 60 along its central axis A4 is preferably less than or equal to the width (D4) of the inlet E40. By ensuring that the maximum length along the central axis A4 is less than or equal to the width (D4) of the inlet E40, the refrigerant can be distributed more effectively to the portion of the cooling channel C3 closer to the inlet E40 compared to the case where the maximum length exceeds the width of the inlet E40.

Furthermore, as mentioned above, each projection 60 and each of the multiple fins 3 are positioned on the first base 21. Each projection 60 overlaps with the multiple fins 3 when viewed from the direction in which the refrigerant introduction channel C1 and the cooling channel C3 overlap. Therefore, compared to the case where each projection 60 does not overlap with the multiple fins 3 in a side view, the flow rate of refrigerant guided by the multiple fins 3 can be increased.

Furthermore, by positioning the rectifier 6 near the inlet E40, the Coanda effect can be effectively utilized. Specifically, the rectifier 6 is preferably positioned within a range from the inlet E40 to 15% of the length along the longitudinal direction of the inner wall surface of the side wall 23. By positioning the rectifier 6 within this range, the refrigerant can be distributed particularly efficiently to the region of the cooling flow path C3 near the inlet E40.

Furthermore, the height T6 may be greater than or equal to the height T3. Also, the heights T6 of the multiple protrusions 60 are equal to each other, but may be different. Also, the edges of the end face 62 do not need to be curved. Furthermore, although the cooling device 1 has multiple protrusions 60, the number of protrusions 60 may be just one. Also, the number of protrusions 60 may be two, four or more. Also, the shapes of each protrusion 60 are identical to each other, but may be different.

1-7. Modifications The first embodiment described above can be modified in various ways, for example, as described below. Furthermore, these modifications may be combined as appropriate.

1-7a. First Modified Example Figure 8 shows the rectifier section 6b of the first modified example. The shape of each projection 60b of the rectifier section 6b shown in Figure 8 differs from that of each projection 60 shown in Figure 4 when viewed from above. The shape of each projection 60b when viewed from above is circular. The side surface 61b of each projection 60b has a curved surface, similar to each projection 60. A part of the side surface 61b with a curved surface is located inside the virtual space V40. Therefore, due to the Coanda effect, the direction of the refrigerant traveling in a straight line in the X1 direction can be changed to the Y1 direction. In other words, due to the Coanda effect, the refrigerant travels along the side surface 61b as shown by arrow a10 in Figure 9. Therefore, the rectifier section 6b can also guide the refrigerant immediately after it flows in from the inlet pipe 4 toward the multiple fins 3.

Furthermore, the length D61 of each projection 60b along its central axis A4, i.e., its diameter, is less than or equal to the width of the inlet E40. Because the diameter is less than or equal to the width of the inlet E40, the refrigerant can be distributed more effectively to the portion of the cooling channel C3 closer to the inlet E40 compared to when the diameter exceeds the width of the inlet E40.

Furthermore, the center C6 of each projection 60b in a plan view is located closer to the multiple fins 3 than to the virtual space V40. The point 65 closest to the inlet E40 in the plan view contour of each projection 60b is located closer to the multiple fins 3 than to the virtual space V40. Each projection 60b is located closer to the multiple fins 3 than to the central axis A4.

1-7b. Second Modified Example Figure 9 shows the rectifier section 6c of the second modified example. The shape of each projection 60c of the rectifier section 6c shown in Figure 9 differs from that of each projection 60 shown in Figure 4 when viewed from above. The shape of each projection 60c when viewed from above is a crescent shape with a part of a circle cut out. The side surface 61c of each projection 60c includes a curved surface 611 and a flat surface 612. The curved surface 611 faces away from the plurality of fins 3. The flat surface 612 faces the plurality of fins 3.

As described above, the side surface 61c of each projection 60c includes a flat surface 612 facing the multiple fins 3. Therefore, the flow along the curved surface 611 is obstructed, making it easier to generate a separated flow in the direction indicated by arrow a20 in Figure 10. Thus, a large amount of refrigerant can be guided to the vicinity of the third side portion 233 of the cooling channel C3 by the refrigerant traveling in the direction indicated by arrow a10 due to the Coanda effect and the refrigerant traveling in the direction indicated by arrow a20 due to the separated flow.

Furthermore, the center C6 of each projection 60c in plan view is located closer to the multiple fins 3 than to the virtual space V40. This center C6 is the geometric center of the planar shape of the projection 60. The point 65 closest to the inlet E40 in the planar contour of each projection 60c is located closer to the multiple fins 3 than to the virtual space V40. Each projection 60c is located closer to the multiple fins 3 than to the central axis A4.

1-7c. Third Modified Example Figure 10 shows the flow straightening section 6d of the third modified example. The shape of each projection 60d of the flow straightening section 6d shown in Figure 10 differs from that of each projection 60 shown in Figure 4 when viewed from above. The shape of each projection 60d when viewed from above is teardrop-shaped, with a part of the circle pointed. The side surface 61d of each projection 60d includes a curved surface 613, a flat surface 614 facing the multiple fins 3, and a flat surface 615 facing the third side portion 233. The curved surface 613 faces away from the multiple fins 3. In addition, each projection 60d is positioned so that the connection portion 63 between the flat surface 614 and the flat surface 615 is not located in the upstream portion.

As described above, the side surface 61d of each projection 60d includes a flat surface 614 facing the multiple fins 3. Therefore, the flow along the flat surface 615 is obstructed, making it easier to generate a separated flow in the direction indicated by arrow a20 in Figure 10. Thus, a large amount of refrigerant can be guided to the region near the third side portion 233 of the cooling channel C3 by the refrigerant traveling in the direction indicated by arrow a10 due to the Coanda effect and the refrigerant traveling in the direction indicated by arrow a20 due to the separated flow.

Furthermore, the center C6 of each projection 60d in plan view is located closer to the multiple fins 3 than to the virtual space V40. This center C6 is the geometric center of the planar shape of the projection 60. The point 65 closest to the inlet E40 in the planar contour of each projection 60d is located closer to the multiple fins 3 than to the virtual space V40. Each projection 60d is located closer to the multiple fins 3 than to the central axis A4.

1-7d. Fourth Modified Example Figure 11 shows the rectifier section 6e of the fourth modified example. The end faces 62e of each projection 60e of the rectifier section 6e shown in Figure 11 have a different shape from the end faces 62 of each projection 60 shown in Figure 4. The end face 62e includes an inclined portion 621, which is a curved portion facing away from the plurality of fins 3. The inclined portion 621 is formed by cutting out a part of the end face 62e. The inclined portion 621 is curved. The inclined portion 621 faces away from the plurality of fins 3. In other words, the inclined portion 621 faces downstream of the refrigerant.

The end face 62e has a curved inclined portion 621, which, due to the Coanda effect at the inclined portion 621, allows the refrigerant spreading from the introduction pipe 4 in the X1 direction to be guided in the Y1 direction. Therefore, compared to the case without the inclined portion 621, the flow rate of refrigerant guided to the multiple fins 3 can be increased.

Furthermore, the center C6 of each projection 60e in a plan view is located closer to the multiple fins 3 than to the virtual space V40. The point 65 closest to the inlet E40 in the plan view contour of each projection 60e is located closer to the multiple fins 3 than to the virtual space V40. Each projection 60e is located closer to the multiple fins 3 than to the central axis A4.

1-7e. Other Modifications Figures 12 and 13 show other examples of the arrangement of the outlet pipe 5 shown in Figure 2. The arrangement of the inlet pipe 4 and outlet pipe 5 is not limited to the example shown in Figure 4.

For example, in the example shown in Figure 12, the outlet pipe 5a is connected to the fourth side portion 234. The outlet pipe 5a is positioned diagonally to the inlet pipe 4, similar to the outlet pipe 5 shown in Figure 4. The refrigerant introduced from the inlet pipe 4 flows in the direction indicated by arrow a1 due to the presence of the protrusion 222, and in the direction indicated by arrow a2 due to the presence of the flow straightening portion 6. In the cooling channel C3, the refrigerant flows in the direction indicated by arrow a3. Then, in the refrigerant outlet channel C2, the refrigerant flows in the direction indicated by arrow a4 towards the outlet E50.

Furthermore, in the example shown in Figure 13, the outlet pipe 5b is connected to the third side portion 233, similar to the inlet pipe 4. Therefore, the outlet pipe 5b is not positioned diagonally to the inlet pipe 4. Even in this case, the refrigerant can be diffused throughout the entire cooling channel C3, just as in the case where they are positioned diagonally. Thus, uneven flow is suppressed. The refrigerant introduced from the inlet pipe 4 flows in the direction indicated by arrow a1 due to the presence of the protrusion 222, and in the direction indicated by arrow a2 due to the presence of the flow straightening portion 6. In the cooling channel C3, the refrigerant flows in the direction indicated by arrow a3. Then, in the refrigerant outlet channel C2, the refrigerant flows in the direction indicated by arrow a6 towards the outlet E50.

2. Second Embodiment A second embodiment of the present disclosure will now be described. For elements whose operation and function are the same as those of the first embodiment described above, the reference numerals used in the description of the first embodiment will be reused, and detailed descriptions of each will be omitted as appropriate.

2-1. Rectifier section 7
Figure 14 is a perspective view showing the cooling device 1A of the second embodiment. Figure 15 is a plan view of the cooling device 1A shown in Figure 14. Figure 16 is a cross-sectional view of the cooling device 1A shown in Figure 14. As shown in Figures 14, 15, and 16, the cooling device 1A has a flow straightening section 7 instead of the flow straightening section 6 of the first embodiment. The flow straightening section 7 straightens the refrigerant inside the housing 2 by adjusting the direction of flow of the refrigerant introduced from the introduction pipe 4. Specifically, the flow straightening section 7 is provided to make the flow of refrigerant in the cooling channel C3 more uniform. In this embodiment, the flow straightening section 7 has a first plate 71 and a second plate 72.

As shown in Figure 15, the first plate 71 and the second plate 72 are each positioned in the refrigerant introduction channel C1 of the housing 2. Each of the first plate 71 and the second plate 72 is a plate whose longitudinal direction is along the central axis A4 of the introduction path E4. Each of the first plate 71 and the second plate 72 extends in the X1 direction from near the inlet E40 of the introduction pipe 4. Each of the first plate 71 and the second plate 72 is spaced apart from the inlet E40 of the introduction pipe 4. Furthermore, the first plate 71 and the second plate 72 are arranged parallel to each other and aligned in the Y2 direction. In a plan view, the first plate 71 is positioned between the second plate 72 and the multiple fins 3. The second plate 72 is positioned further from the multiple fins 3 than the first plate 71. The second plate 72 is located between the first plate 71 and the second side portion 232.

As shown in Figures 14 and 15, the first plate 71 and the second plate 72 each protrude from the first base 21 toward the second base 22. Each of the first plate 71 and the second plate 72 is positioned on the side 202 opposite to the cooling surface 201 of the first base 21. Furthermore, each of the first plate 71 and the second plate 72 is in contact with the substrate 221.

Figure 17 is an enlarged view of the rectifier section 7 shown in Figure 15. As shown in Figure 17, the length L72 of the second plate 72 in the X1 direction is longer than the length L71 of the first plate 71 in the X1 direction. That is, the length of the plate decreases as it approaches the multiple fins 3. Also, the length L72 of the second plate 72 is longer than half the length of the housing 2 in the longitudinal direction. The length L71 of the first plate 71 is shorter than half the length of the housing 2 in the longitudinal direction.

The first plate 71 is positioned inside the virtual space V40. The second plate 72 is positioned further away from the multiple fins 3 than the virtual space V40. In the illustrated example, the second plate 72 is positioned so as to be in contact with the virtual space V40. Note that the second plate 72 may also be positioned inside the virtual space V40.

The first plate 71 has a tip 711 and a base 712. The base 712 is located closer to the inlet E40 of the inlet pipe 4 than the tip 711. The second plate 72 has a tip 721 and a base 722. The base 722 is located closer to the inlet E40 of the inlet pipe 4 than the tip 721. Neither the base 712 nor the base 722 are in contact with the inlet E40.

The first distance D71 between the first plate 71 and the multiple fins 3 is greater than the second distance D72 between the first plate 71 and the second plate 72. Also, the third distance D73 between the second plate 72 and the second side portion 232 is greater than the second distance D72. Furthermore, the first distance D71 is greater than the third distance D73. Note that the relationships between these distances are not limited to those described above.

According to the cooling device 1A of this embodiment, uneven flow of the refrigerant within the housing 2 can be suppressed. In particular, uneven flow of the refrigerant in the cooling channel C3 can be suppressed.

Figure 18 shows the flow of refrigerant within the cooling device 1A shown in Figure 15. As described above, the cooling device 1A has a flow straightening section 7 located in the refrigerant introduction channel C1. The first plate 71 and the second plate 72 of the flow straightening section 7 each have their longitudinal direction aligned with the central axis A4 of the introduction pipe 4. The length L72 of the second plate 72 in the X1 direction is longer than the length L71 of the first plate 71 in the X1 direction.

With the rectifier section 7 in place, a portion of the refrigerant flowing in from the inlet E40 first passes between the second side section 232 and the second plate 72 and proceeds towards the fourth side section 234. This portion of the refrigerant then moves in the direction indicated by arrow a6. Another portion of the refrigerant flowing in from the inlet E40 passes between the first plate 71 and the second plate 72, maintaining a straight line along the second plate 72 and proceeding towards the fourth side section 234. This portion of the refrigerant then moves in the direction indicated by arrow a7. Therefore, the refrigerant can be efficiently distributed to region S1b shown in Figure 6, i.e., the region of the cooling flow path C3 near the outlet E50.

Furthermore, the remaining refrigerant flowing in from the inlet E40 has its straight-line propagation in the X1 direction mitigated by the first plate 71, and proceeds while spreading in the Y1 direction. That is, it proceeds in the direction indicated by arrow a8 in Figure 18. Therefore, the refrigerant can be efficiently distributed to the region S1a shown in Figure 6, i.e., the region of the cooling channel C3 near the inlet E40.

As described above, the rectifier section 7 allows the refrigerant to diffuse throughout the entire cooling channel C3, thereby suppressing uneven flow in the cooling channel C3. Therefore, uniformity of the refrigerant in the cooling channel C3 can be achieved. This reduces variations in cooling performance within the cooling surface 201, thus improving the cooling performance of the cooling device 1A. Consequently, variations in temperature differences within the heating element 100 in contact with the cooling surface 201 can be reduced. For example, if the heating element 100 includes multiple semiconductor elements, the temperature difference between these semiconductor elements is suppressed. Therefore, sufficient output from each semiconductor element can be ensured.

Furthermore, if the flow velocity of the refrigerant flowing in from the inlet E40 is high, the refrigerant will flow further, but the straightness of the flow will increase. Therefore, it becomes difficult for the refrigerant to reach the region of the cooling channel C3 near the inlet E40. In this case, the length L71 of the first plate 71 is shortened, and the first distance D71 is increased. This increases the flow rate of the refrigerant flowing into the region of the cooling channel C3 near the inlet E40. Thus, the refrigerant can be efficiently distributed to the region of the cooling channel C3 near the inlet E40.

Furthermore, if the flow velocity of the refrigerant flowing in from the inlet E40 is low, the refrigerant will have difficulty reaching the region of the cooling channel C3 furthest from the inlet E40. In this case, the length L72 of the second plate 72 is increased. By increasing the length, the straightness of the refrigerant flow along the second plate 72 is maintained. In addition, the third distance D73 between the second plate 72 and the second side portion 232 is increased. By increasing this distance, the flow rate of the refrigerant flowing between the second plate 72 and the second side portion 232 can be increased. Therefore, the refrigerant can be efficiently distributed to the region of the cooling channel C3 near the outlet E50.

In this way, by changing the configuration of the flow straightening section 7 according to the flow velocity, the flow path and flow rate distribution of the refrigerant can be changed. As a result, uneven flow in the cooling path C3 can be suppressed, and the cooling performance on the cooling surface 201 can be made uniform. Therefore, the cooling performance of the cooling device 1A is improved.

Furthermore, as mentioned above, the inlet pipe 4 is connected to the third side portion 233. Therefore, compared to, for example, the case where the inlet pipe 4 is connected to the substrate 221, the refrigerant flow is more easily maintained in a straight line in the X1 direction. For this reason, in the case of the cooling device 1A where the inlet pipe 4 is connected to the third side portion 233, the effect of providing the flow straightening section 7 is particularly easily demonstrated. Note that the inlet pipe 4 may be connected to a location other than the third side portion 233; for example, it may be connected to the substrate 221 or the second side portion 232.

Furthermore, the cooling device 1A has a protrusion 222 on the second base portion 22. With the configuration having the protrusion 222, the flow area in the cooling channel C3 is narrower compared to the configuration without the protrusion 222. Therefore, the flow velocity of the refrigerant increases, and thus the cooling efficiency in the cooling channel C3 can be improved. Thus, the cooling efficiency of the cooling surface 201 can be improved.

Furthermore, the lengths of the first plate 71 and the second plate 72 in the Z2 direction are equal to the distance from the first base 21 to the substrate 221. Therefore, compared to the case where the length is shorter than this distance, the refrigerant can be efficiently distributed to the area near the inlet E40. Note that this length may be shorter than this distance, and may, for example, be equal to the length of each fin 3. Therefore, the first plate 71 and the second plate 72 do not necessarily have to be in contact with the substrate 221.

Furthermore, although the second plate 72 does not contact the inlet E40 of the inlet pipe 4, the second plate 72 may contact the inlet pipe 4 or the third side portion 233. Also, the thickness of the first plate 71 and the second plate 72 is not particularly limited, but it is less than 1/3 of the width D4 of the inlet passage E4.

2-2. Modifications The second embodiment described above can be modified in various ways, for example, as described below. Furthermore, these modifications may be combined as appropriate.

2-2a. Fifth Modification Figure 19 shows the rectifier section 7a of the fifth modification. The first plate 71a and the second plate 72a of the rectifier section 7a shown in Figure 19 are bent in the middle. Specifically, the first plate 71a is bent toward the multiple fins 3 at a position closer to the tip 711 than to the base 712. Similarly, the second plate 72a is bent toward the multiple fins 3 at a position closer to the tip 721 than to the base 722. The first plate 71a and the second plate 72a are bent toward the outlet E50.

The bending of the first plate 71a and the second plate 72a allows for directional flow of the refrigerant. Therefore, the flow straightening section 7a shown in Figure 20 allows for more efficient distribution of the refrigerant to the area near the outlet E50 within the cooling channel C3 compared to the flow straightening section 7 shown in Figure 15.

2-2b. Sixth Modification Figure 20 shows the rectifier section 7b of the sixth modification. The rectifier section 7b shown in Figure 20 has a plurality of protrusions 60 of the first embodiment, a first plate 71a, and a second plate 72a. With the rectifier section 7b, the Coanda effect of each protrusion 60 and the action of the first plate 71a and the second plate 72a allow the refrigerant to be efficiently distributed to the region near the inlet E40 and the region near the outlet E50 of the cooling flow path C3. For example, the first plate 71a may be omitted. Alternatively, a first plate 71 and a second plate 72 may be provided instead of the first plate 71a and the second plate 72a. Alternatively, any of the protrusions of the first to fifth modifications may be provided instead of the protrusions 60.

3. Third Embodiment The third embodiment of the present disclosure will now be described. For elements whose operation and function are the same as those of the first embodiment described above, the reference numerals used in the description of the first embodiment will be reused, and detailed descriptions of each will be omitted as appropriate.

3-1. Rectifier section 8
Figure 21 is a perspective view showing the cooling device 1B of the third embodiment. Figure 22 is a plan view of the cooling device 1B shown in Figure 21. Figure 23 is a cross-sectional view of the cooling device 1B shown in Figure 21. As shown in Figures 21, 22 and 23, the cooling device 1B has a flow straightening section 8 instead of the flow straightening section 6 of the first embodiment. The flow straightening section 8 straightens the refrigerant in the housing 2 by adjusting the direction of flow of the refrigerant introduced from the introduction pipe 4. Specifically, the flow straightening section 8 is provided to make the flow of refrigerant in the cooling channel C3 more uniform. In this embodiment, the flow straightening section 8 has a flat plate 80.

As shown in Figures 21 and 22, the flat plate 80 is positioned in the refrigerant introduction channel C1 of the housing 2. Specifically, as shown in Figure 23, the flat plate 80 is positioned on the substrate 221. A portion of the substrate 221 forms part of the wall surface of the refrigerant introduction channel C1. Furthermore, since the flat plate 80 is in contact with the substrate 221, it can also be said to be positioned on the first base portion 21.

The flat plate 80 is a plate whose longitudinal direction is along the central axis A4 of the introduction path E4. Furthermore, as shown in Figure 22, the flat plate 80 is positioned near the boundary between the refrigerant introduction path C1 and the cooling path C3. The flat plate 80 also functions as a partition plate separating the refrigerant introduction path C1 and the cooling path C3.

As shown in Figure 23, the flat plate 80 has a plurality of first through holes 81, a plurality of second through holes 82, and a plurality of third through holes 83. These through holes are provided throughout the entire area of the flat plate 80 in the X1 direction. The plurality of first through holes 81, the plurality of second through holes 82, and the plurality of third through holes 83 are spaced apart from each other and are arranged in a line in the X1 direction in this order. Therefore, the plurality of second through holes 82 are located between the plurality of first through holes 81 and the plurality of third through holes 83. The plurality of first through holes 81 are positioned closer to the inlet E40 than the plurality of second through holes 82. The plurality of third through holes 83 are positioned further from the inlet E40 than the plurality of second through holes 82. Also, two adjacent first through holes 81 are spaced apart from each other, two adjacent second through holes 82 are spaced apart from each other, and two adjacent third through holes 83 are spaced apart from each other.

These through-holes face the multiple fins 3. Therefore, when viewed from the Y1 direction, which is the direction in which the refrigerant introduction channel C1 and the cooling channel C3 overlap, these through-holes overlap the multiple fins 3. Furthermore, when viewed from this direction, the shape of these through-holes is rectangular.

The width D81 of each first through-hole 81 is greater than the width D82 of each second through-hole 82. Also, the width D81 of each first through-hole 81 is greater than the width D83 of each third through-hole 83. Furthermore, the width D83 of each third through-hole 83 is greater than the width D82 of each second through-hole 82. The heights of the multiple first through-holes 81, multiple second through-holes 82, and multiple third through-holes 83 are equal to each other. Therefore, the areas of the first through-holes 81, the third through-holes 83, and the second through-holes 82 are in this order of increasing size.

Note that the widths D81, D82, and D83 are lengths in the X1 direction. Also, each height is a length in the Z1 direction. Furthermore, the widths of the first through-hole 81, second through-hole 82, and third through-hole 83 may be equal, while the heights of the first through-hole 81, second through-hole 82, and third through-hole 83 may differ, so that the areas of the first through-hole 81, third through-hole 83, and second through-hole 82 are in that order of increasing size.

Furthermore, in the illustrated example, the distances between the centers of these through-holes are equal. However, these distances may differ. Also, the number of through-holes is not particularly limited. However, the total area of the multiple first through-holes 81, the total area of the multiple third through-holes 83, and the total area of the multiple second through-holes 82 are in that order of increasing size.

According to the cooling device 1B of this embodiment, uneven flow of the refrigerant within the housing 2 can be suppressed. In particular, uneven flow of the refrigerant in the cooling channel C3 can be suppressed.

Figure 24 shows the flow of refrigerant within the cooling device shown in Figure 21. As mentioned above, the cooling device 1B has a flow straightening section 8. The flow straightening section 8 has a flat plate 80 positioned in the refrigerant introduction channel C1. Having this flat plate 80 makes it easier for the refrigerant to travel in the X1 direction compared to the case without the flat plate 80. In particular, because the flat plate 80 is positioned along the central axis A4, the refrigerant easily travels in the X1 direction.

Furthermore, the flat plate 80 has multiple first through-holes 81, multiple second through-holes 82, and multiple third through-holes 83. These through-holes overlap with the multiple fins 3 when viewed from the direction in which the refrigerant introduction channel C1 and the cooling channel C3 overlap. Therefore, the refrigerant in the refrigerant introduction channel C1 flows through each through-hole in the direction indicated by arrow a9 and moves into the cooling channel C3.

As mentioned above, the area of the first through-hole 81 is larger than the area of the second through-hole 82. Near the inlet E40 of the refrigerant introduction flow path C1, the refrigerant is less likely to circulate than in the center of the refrigerant introduction flow path C1 in the X1 direction. Therefore, by making the area of the first through-hole 81 larger than that of the second through-hole 82, a larger amount of refrigerant can be circulated near the inlet E40 rather than in the center of the cooling flow path C3. Also, as mentioned above, the area of the third through-hole 83 is larger than that of the second through-hole 82. On the side opposite the inlet E40 of the refrigerant introduction flow path C1, the refrigerant is less likely to circulate than in the center of the refrigerant introduction flow path C1 in the X1 direction. Therefore, by making the area of the third through-hole 83 larger than that of the second through-hole 82, a larger amount of refrigerant can be circulated on the side opposite the inlet E40 rather than in the center of the cooling flow path C3. Thus, the flow rate distribution at each through-hole is equalized, and uneven flow of refrigerant can be suppressed.

As described above, the rectifier section 8 allows the refrigerant to diffuse throughout the entire cooling channel C3, thereby suppressing uneven flow in the cooling channel C3. Therefore, uniformity of the refrigerant in the cooling channel C3 can be achieved. This reduces variations in cooling performance within the cooling surface 201, thus improving the cooling performance of the cooling device 1A. Consequently, variations in temperature differences within the heating element 100 in contact with the cooling surface 201 can be reduced. For example, if the heating element 100 includes multiple semiconductor elements, the temperature difference between these semiconductor elements is suppressed. Therefore, sufficient output from each semiconductor element can be ensured.

Furthermore, if the distance from the inlet E40 to the multiple fins 3 is long, if the flow rate of the refrigerant flowing in from the inlet E40 is high, or if the distance between the inlet E40 and the outlet E50 is short, the refrigerant may not reach the area near the inlet E40 within the cooling channel C3. In these cases, the area of the first through-hole 81 is made larger than the area of the third through-hole 83. By doing so, the flow rate of the refrigerant to the area near the inlet E40 within the cooling channel C3 can be increased.

Furthermore, as mentioned above, the inlet pipe 4 is connected to the third side portion 233. Therefore, compared to, for example, the case where the inlet pipe 4 is connected to the substrate 221, the refrigerant flow is more easily maintained in a straight line in the X1 direction. For this reason, in the case of the cooling device 1B where the inlet pipe 4 is connected to the third side portion 233, the effect of providing the flow straightening section 8 is particularly easily demonstrated. Note that the inlet pipe 4 may be connected to a location other than the third side portion 233; for example, it may be connected to the substrate 221 or the second side portion 232.

Furthermore, the cooling device 1B has a protrusion 222 on the second base portion 22. With the configuration having the protrusion 222, the flow path area in the cooling channel C3 is narrowed compared to the configuration without the protrusion 222. Therefore, the flow velocity of the refrigerant increases, and thus the cooling efficiency in the cooling channel C3 can be improved.

3-2. Modifications The third embodiment described above can be modified in various ways, for example, as described below. Furthermore, these modifications may be combined as appropriate.

3-2a. Seventh Modification Figure 25 shows the flow straightening section 8a of the seventh modification. The flow straightening section 8a shown in Figure 25 has different areas for each through-hole in the flat plate 80a compared to the flow straightening section 8a shown in Figure 23. Specifically, the width D81 of each first through-hole 81a is smaller than the width D83 of each third through-hole 83. The width D81 of each first through-hole 81a is larger than the width D82 of each second through-hole 82. The width D83a of each third through-hole 83a is larger than the width D82 of each second through-hole 82. Also, the heights of the multiple first through-holes 81a, multiple second through-holes 82, and multiple third through-holes 83a are equal to each other. Therefore, the area of the third through-hole 83a, the area of the first through-hole 81a, and the area of the second through-hole 82 are larger in that order.

If the distance from the inlet E40 to the multiple fins 3 is short, if the flow rate of the refrigerant flowing in from the inlet E40 is small, or if the distance between the inlet E40 and the outlet E50 is long, the refrigerant will not easily reach the area near the outlet E50 in the cooling channel C3. In these cases, the area of the third through-hole 83a is made larger than the area of the first through-hole 81a. This increases the flow rate of the refrigerant to the area near the inlet E40 in the cooling channel C3.

3-2b. Eighth Modification Figure 26 is a perspective view showing the eighth modification of the cooling device 1Bb. Figure 27 is a plan view of the cooling device 1Bb shown in Figure 26. Figure 28 is a cross-sectional view of the cooling device 1Bb shown in Figure 27. The rectifier section 8b of the cooling device 1Bb shown in Figures 26, 27, and 28 has a different arrangement from the rectifier section 8 shown in Figure 22. For example, the flat plate 80b of the rectifier section 8b is placed on the substrate 221, extends in the Z1 direction, and bends in the Y2 direction midway. The flat plate 80b is placed in the refrigerant introduction flow path C1, similar to the flat plate 80.

As shown in Figure 27, the flat plate 80b has a portion that overlaps with a part of the substrate 221 in a plan view. Each of the multiple first through holes 81, multiple second through holes 82, and multiple third through holes 83 overlaps with a part of the substrate 221 in a plan view. In the case of the flat plate 80b, the height of each through hole is the length in the Y1 direction.

As described above, each through-hole in the flat plate 80b overlaps with a portion of the substrate 221 in a plan view. The flow straightening section 8b, having such a flat plate 80b, can suppress refrigerant flow deviation within the housing 2, similar to the flow straightening section 8. In particular, it can suppress refrigerant flow deviation in the cooling channel C3. Furthermore, the refrigerant flow can be agitated by causing the refrigerant to collide with the flat plate 80b in the refrigerant introduction channel C1. Therefore, by homogenizing the refrigerant flow velocity, flow deviation can be suppressed.

As shown in Figure 27, each of the multiple first through-holes 81, multiple second through-holes 82, and multiple third through-holes 83 is located on the side of the flat plate 80b opposite to the multiple fins 3. That is, each through-hole is located closer to the second side portion 232 than the center line A8 along the X1 direction of the flat plate 80b. Each of the multiple second through-holes 82 and multiple third through-holes 83 is located further from the multiple fins 3 than the center line A8 along the X1 direction of the flat plate 80b. Therefore, compared to the case where the holes are located closer to the multiple fins 3 than the center line A8, it is easier to distribute the refrigerant uniformly through the cooling channel C3. The increased distance between the flat plate 80b and the multiple fins 3 makes the refrigerant flow less susceptible to sudden contractions or expansions as it passes through each through-hole. Thus, it is easier to achieve uniform distribution of the refrigerant in the cooling channel C3. In particular, by positioning the flat plate 80b so that each through-hole overlaps with a portion of the substrate 221 in a plan view, the spacing between each through-hole and the multiple fins 3 can be increased compared to the aforementioned flat plate 80.

Furthermore, each through-hole may be positioned closer to the fins 3 than the center line A8. Also, in the illustrated example, the multiple second through-holes 82 and the multiple third through-holes 83 are positioned further from the fins 3 than the center axis A4, but they may also be positioned closer to the fins 3 than the center axis A4.

Furthermore, as shown in Figure 28, the position of the upper surface of the flat plate 80b in the Z1 direction is approximately equal to the position of the lower ends of the multiple fins 3 in the Z1 direction. However, the position of the upper surface of the flat plate 80b in the Z1 direction is not particularly limited. However, it is preferable that the position of the upper surface of the flat plate 80b in the Z1 direction is equal to or below the lower ends of the multiple fins 3. By positioning the upper surface of the flat plate 80b in this way, a larger amount of refrigerant can be efficiently distributed to the cooling channel C3 compared to when the upper surface is positioned above the lower ends of the multiple fins 3.

Furthermore, as mentioned above, the shape of each through-hole is rectangular. Compared to a circular shape, this design suppresses shape loss due to rapid contraction or expansion as the refrigerant passes through each through-hole.

The cooling device of the present invention has been described above based on the illustrated embodiments, but the present invention is not limited to these. Furthermore, the configuration of each part of the present invention can be replaced with any configuration that performs a similar function to the embodiments described above, and any additional configurations can also be added.

1...Cooling device, 1A...Cooling device, 1B...Cooling device, 1Bb...Cooling device, 1X...Cooling device, 2...Housing, 3...Fin, 4...Introduction pipe, 5...Outlet pipe, 5a...Outlet pipe, 5b...Outlet pipe, 6...Rectifier, 6b...Rectifier , 6c... rectifier, 6d... rectifier, 6e... rectifier, 7... rectifier, 7a... rectifier, 7b... rectifier, 8... rectifier, 8a... rectifier, 8b... rectifier, 21... first base, 22... second base, 23... side wall, 40... inside Wall surface, 50...Inner wall surface, 60...Protrusion, 60a...Protrusion, 60b...Protrusion, 60c...Protrusion, 60d...Protrusion, 60e...Protrusion, 61...Side surface, 61a...Side surface, 61b...Side surface, 61c...Side surface, 61d...Side surface, 62...End surface, 62e...End surface, 63...Connection part, 65...Point, 71...First plate, 71a...First plate, 72...Second plate, 72a...Second plate, 80...Flat plate, 80a...Flat plate, 80b...Flat plate, 81...First through hole, 81a...First through Through hole, 82...Second through hole, 83...Third through hole, 83a...Third through hole, 100...Heating element, 201...Cooling surface, 202...Surface, 221...Substrate, 222...Protrusion, 231...First side, 232...Second side, 233...Third side, 234...Fourth side, 611...Curved surface, 612...Flat surface, 613...Curved surface, 614...Flat surface, 615...Flat surface, 621...Inclined surface, 711...Tip, 712...Base end, 721...Tip, 722...Base end A0...centerline, A4...central axis, A5...central axis, A8...centerline, C1...refrigerant inlet path, C2...refrigerant outlet path, C3...cooling path, D71...first distance, D72...second distance, D73...third distance, E4...inlet path, E40...inlet port, E5...outlet path, E50...outlet port, C6...center, S1a...region, S1b...region, T3...height, T6...height, V4...virtual extension plane, V40...virtual space, L71...length, L72...length.

Claims (10)

A housing comprising a first base having a cooling surface for cooling a heat-generating element and a surface opposite to the cooling surface, and a second base spaced apart from the first base and facing the opposite surface,
A plurality of cooling fins are arranged within the housing and protrude from the first base toward the second base,
An introduction pipe connected to the housing and having an introduction path for introducing refrigerant into the housing,
An outlet pipe connected to the housing and having an outlet passage for discharging the refrigerant from inside the housing,
The enclosure comprises a flow straightening section for straightening the refrigerant within the enclosure,
The inside of the housing is divided into a refrigerant introduction channel connected to the introduction channel, a refrigerant discharge channel connected to the discharge channel, and a cooling channel located between the refrigerant introduction channel and the refrigerant discharge channel in a plan view, where the plurality of fins are arranged.
The second base portion has a plate-shaped substrate and a convex portion that protrudes from the substrate toward the first base portion and overlaps with the plurality of fins in a plan view .
The rectifier is arranged in the refrigerant introduction path of the housing,
The rectifying portion has a projection that extends from the first base toward the second base,
The flat area of the aforementioned protrusion is larger than the flat area of each of the plurality of fins.
The projection has a side surface including a curved surface,
A part or all of the curved surface is located within a virtual space surrounded by a virtual extension of the inner wall surface of the inlet pipe.
A cooling device characterized by the following features. The shape of the housing in plan view is rectangular.
The shape of the convex portion in plan view is a rectangle along the longitudinal direction of the housing,
The housing has a side wall portion connecting the first base portion and the second base portion,
The side wall portion has a first side portion along the longitudinal direction of the housing, a second side portion spaced apart from the first side portion and also along the longitudinal direction of the housing, a third side portion connecting the first side portion and the second side portion, and a fourth side portion connecting the first side portion and the second side portion and spaced apart from the third side portion.
The introduction pipe is connected to the third side portion.
The cooling device according to claim 1. The center of the projection in a plan view is located closer to the plurality of fins than to the virtual space.
The cooling device according to claim 1 or 2 . The point in the plan view of the projection that is closest to the inlet of the inlet tube is located closer to the plurality of fins than to the virtual space.
A cooling device according to any one of claims 1 to 3 . The side surface of the projection includes a flat surface facing the plurality of fins,
A cooling device according to any one of claims 1 to 4 . The rectifier section has a first plate and a second plate,
Each of the first plate and the second plate protrudes from the first base toward the second base, with its longitudinal direction aligned with the central axis of the introduction pipe.
The second plate is positioned further away from the plurality of fins than the first plate.
The length of the second plate is longer than the length of the first plate.
The cooling device according to claim 1 or 2. Each of the first plate and the second plate has a tip and a base that is positioned closer to the introduction tube than the tip,
Each of the first plate and the second plate is curved toward the plurality of fins at a position closer to the tip than to the base end.
The cooling device according to claim 6 . The rectifier section has a flat plate placed in the refrigerant introduction channel,
The flat plate includes a first through hole and a second through hole having an area smaller than the area of the first through hole.
The first through-hole is positioned closer to the inlet of the inlet pipe than the second through-hole.
The cooling device according to claim 1 or 2. The first through-hole and the second through-hole overlap with the plurality of fins when viewed from the direction in which the refrigerant introduction passage and the cooling passage overlap.
The cooling device according to claim 8 . The first through-hole and the second through-hole overlap with a portion of the substrate in a plan view.
The cooling device according to claim 8 or 9 .