Radiators and heat exchangers

Abstract

The refrigerant flow path (2) of the radiator (1) comprises a refrigerant inlet (21), a refrigerant outlet (22), a refrigerant contact part (23), a refrigerant relay part (25) and a connection part (24). The refrigerant contact parts (23) are arranged at intervals from each other along the refrigerant path from the refrigerant inlet (21) to the refrigerant outlet (22), and are configured to enable the cooling wall part and the refrigerant to contact each other. The refrigerant relay part (25) is arranged between adjacent refrigerant contact parts (23), and is configured to enable the refrigerant to be relayed from the refrigerant contact part (23) on the upstream side of the refrigerant flow path to the refrigerant contact part (23) on the downstream side. The connection part (24) is located between the refrigerant relay part (25) and the refrigerant contact part (23), and has a flow path cross-sectional area smaller than that of the refrigerant contact part (23) and the refrigerant relay part (25).

Description

Technical Field

[0001] The present invention relates to a radiator and a heat exchanger. Background Art

[0002] In order to cool a heat generating body such as a semiconductor element, a heat exchanger is used, which includes a cooling wall portion on which the heat generating body is mounted. In order to cool the heat generating body more efficiently, fins such as plate fins, pin fins, and corrugated fins are sometimes installed on the cooling wall portion.

[0003] For example, Patent Document 1 discloses a core of a stacked radiator that is formed by stacking metal plates having a plurality of slits and through which cooling water flows. The metal plates constituting the core have a plurality of mutually parallel and elongated longitudinal ribs between the slits and transverse ribs that connect adjacent longitudinal ribs. In addition, the plurality of metal plates are stacked so that the longitudinal ribs are aligned with each other and the positions of the transverse ribs are staggered.

[0004] Prior Art Literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2014-33063 Summary of the invention

[0007] (Problems to be solved by the invention)

[0008] When the refrigerant flows through the radiator, the temperature of the refrigerant flowing through the portion close to the inner surface of the radiator becomes higher than the temperature of the refrigerant flowing through the portion away from the inner surface of the radiator due to heat exchange with the radiator. Since the slit in the core of Patent Document 1 is in a rectangular shape extending along the flow direction of the cooling water, the above-mentioned uneven distribution of the temperature of the cooling water is easily generated in the slit. When such uneven distribution of the temperature of the cooling water occurs, the temperature difference between the core and the cooling water in contact with the core becomes very small, which may lead to a decrease in heat exchange efficiency, thereby causing a decrease in cooling performance.

[0009] The present invention has been made in view of the above background, and an object of the present invention is to provide a radiator capable of improving the cooling performance of a heat exchanger and a heat exchanger including the radiator.

[0010] (Technical solutions to solve problems)

[0011] One embodiment of the present invention is a radiator configured to be installed on a cooling wall portion for cooling a heating element in a heat exchanger, and the radiator has a refrigerant flow path configured to allow refrigerant to flow, the refrigerant flow path having: a refrigerant inlet portion for introducing refrigerant; a refrigerant outlet portion for outlet the refrigerant, a plurality of refrigerant contact portions arranged at intervals from each other along the refrigerant path from the refrigerant inlet portion to the refrigerant outlet portion so that the cooling wall portion and the refrigerant are in contact; a refrigerant relay portion arranged between adjacent refrigerant contact portions and relaying the refrigerant from the refrigerant contact portion on the upstream side of the refrigerant path to the refrigerant contact portion on the downstream side; and a connecting portion located between the refrigerant relay portion and the refrigerant contact portion, and a flow path cross-sectional area of ​​the connecting portion being smaller than the flow path cross-sectional area of ​​the refrigerant contact portion and the flow path cross-sectional area of ​​the refrigerant relay portion.

[0012] (Effects of the Invention)

[0013] The radiator has a refrigerant flow path, wherein the refrigerant flow path has: a plurality of refrigerant contact portions arranged between a refrigerant inlet portion and a refrigerant outlet portion; a refrigerant relay portion relaying the refrigerant from the refrigerant contact portion on the upstream side of the refrigerant path to the refrigerant contact portion on the downstream side; and a connecting portion located between the refrigerant relay portion and the refrigerant contact portion. In addition, the connecting portion has a smaller flow path cross-sectional area than the refrigerant contact portion and the refrigerant relay portion.

[0014] In the refrigerant flow path, when the refrigerant flows from the refrigerant relay part into the refrigerant contact part, the refrigerant passes through the connection part having a smaller flow path cross-sectional area than the refrigerant relay part and the refrigerant contact part. The refrigerant flow path can efficiently stir the refrigerant flowing into the refrigerant contact part by expanding and contracting the flow path. In addition, similar to the refrigerant flowing into the refrigerant contact part, the refrigerant flow path can also efficiently stir the refrigerant flowing from the refrigerant contact part into the refrigerant relay part by expanding and contracting the flow path.

[0015] In this way, the refrigerant flow path is configured to repeatedly expand and contract along the path of the refrigerant, so that the refrigerant flowing in the refrigerant flow path can be efficiently stirred and the unevenness of the refrigerant temperature can be reduced. As a result, the temperature difference between the radiator and the refrigerant in contact with the radiator can be further increased, and the cooling performance can be improved.

[0016] Therefore, according to the above-mentioned radiator, the cooling performance of the heat exchanger can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a perspective view of the heat sink in Embodiment 1.

[0018] Figure 2 It is a top view of the heat sink in Embodiment 1.

[0019] Figure 3 yes Figure 2 Sectional view along line III-III.

[0020] Figure 4 yes Figure 2 Partial cross-sectional view along line IV-IV.

[0021] Figure 5 yes Figure 3 Partial cross-sectional view along line VV.

[0022] Figure 6 This is a plan view of the first fin plate in Embodiment 1 as viewed from the second direction.

[0023] Figure 7 This is a plan view of the second fin plate in Embodiment 1 as viewed from the second direction.

[0024] Figure 8 This is a plan view of the first fin plate having projections and depressions provided in a portion in the longitudinal direction in the second embodiment, as viewed from the second direction.

[0025] Fig. 9 This is a plan view of the first fin plate having projections and depressions in a portion thereof in the lateral direction in the third embodiment, as viewed from the second direction.

[0026] Fig.10 This is a perspective view of a heat exchanger in Embodiment 4.

[0027] Fig.11 It is a top view of the heat exchanger in Embodiment 4.

[0028] Fig.12 yes Fig.11 Sectional view along line XII-XII.

[0029] Fig.13 This is an exploded perspective view of a heat sink in Comparative Example 1 in which a plurality of plates having slits are stacked.

[0030] Fig.14 3 is a top view of the heat sink in Comparative Example 1.

[0031] Fig.15 yes Fig.14 Sectional view along line XV-XV.

[0032] Fig.16 This is a graph comparing the cooling performance of the heat sink of Embodiment 1 with the cooling performance of the heat sink of Comparative Example 1. DETAILED DESCRIPTION

[0033] The radiator may have one refrigerant flow path or may have a plurality of refrigerant flow paths. In the latter case, the refrigerant inlet and refrigerant outlet of each refrigerant flow path may be arranged to be separated from the refrigerant inlet and refrigerant outlet of other refrigerant flow paths. In addition, the plurality of refrigerant flow paths may have a common refrigerant inlet and refrigerant outlet, and the plurality of refrigerant flow paths may be connected side by side between the refrigerant inlet and the refrigerant outlet.

[0034] The refrigerant contact portion may be arranged in contact with the cooling stave portion or may be arranged apart from the cooling stave portion. From the viewpoint of further improving the cooling performance, the refrigerant contact portion is preferably arranged in contact with the cooling stave portion.

[0035] The refrigerant relay part is arranged between adjacent refrigerant contact parts on the refrigerant path in the refrigerant flow path. Preferably, the refrigerant relay part is arranged farther from the cooling wall part than the refrigerant contact part. In this case, the intervals between adjacent refrigerant contact parts can be made narrower, and the number of refrigerant contact parts arranged in each refrigerant flow path can be increased.

[0036] In addition, by arranging the refrigerant relay part at a position farther from the cooling stave part than the refrigerant contact part, the refrigerant can be stirred more efficiently in the refrigerant relay part and the refrigerant contact part. The temperature of the radiator has a tendency to decrease as the distance from the cooling stave part increases. Therefore, the temperature of the refrigerant passing through the part closer to the cooling stave part in the refrigerant contact part tends to become higher due to heat exchange with the cooling stave part, etc. On the other hand, the temperature of the refrigerant passing through the part farther from the cooling stave part in the refrigerant contact part tends to become lower than the temperature of the refrigerant passing through the part closer to the cooling stave part. Therefore, the temperature distribution of the refrigerant flowing out from the refrigerant contact part sometimes becomes uneven.

[0037] Thus, even when there is uneven temperature distribution of the refrigerant flowing out of the refrigerant contact portion, by arranging the refrigerant relay portion at a position farther from the cooling wall portion than the refrigerant contact portion, the refrigerant can be stirred more efficiently and the uneven temperature distribution can be reduced. As a result, the temperature of the refrigerant supplied to the refrigerant contact portion on the downstream side can be made lower than the temperature of the relatively high temperature refrigerant.

[0038] As a result, by arranging the refrigerant relay portion at a position farther from the cooling stave portion than the refrigerant contact portion, the cooling performance of the heat exchanger can be further improved.

[0039] The refrigerant contact part and the refrigerant relay part are connected via a connecting part. The connecting part has a flow path cross-sectional area smaller than that of the refrigerant contact part and the refrigerant relay part. That is, the refrigerant flow path has a portion with the smallest flow path cross-sectional area on the refrigerant path from the refrigerant contact part to the refrigerant relay part, and the portion with the smallest flow path cross-sectional area is called a connecting part. In addition, the above-mentioned flow path cross-sectional area refers to the cross-sectional area of ​​the section in the refrigerant flow path that is orthogonal to the refrigerant flow.

[0040] The connection portion is preferably arranged to connect the refrigerant contact portion and the refrigerant relay portion at the shortest distance. In this case, the increase in pressure loss associated with the reduction in the flow path cross-sectional area can be further suppressed while ensuring the cooling performance improvement effect of the connection portion.

[0041] The refrigerant flow path may include: a second refrigerant relay portion, which is disposed between adjacent refrigerant relay portions and relays the refrigerant from the refrigerant relay portion on the upstream side of the refrigerant path to the refrigerant relay portion on the downstream side; and a second connecting portion, which is located between the second refrigerant relay portion and the refrigerant relay portion and has a smaller flow path cross-sectional area than the refrigerant relay portion and the second refrigerant relay portion. In this case, the refrigerant may be stirred in the second refrigerant relay portion in the same manner as in the refrigerant relay portion.

[0042] In addition, as described above, since the temperature of the radiator tends to decrease as the distance from the cooling wall increases, the temperature of the refrigerant passing through the second refrigerant relay portion tends to be lower than the temperature of the refrigerant passing through the refrigerant contact portion. Therefore, by providing the second refrigerant relay portion, the higher temperature refrigerant flowing in from the refrigerant contact portion through the connection portion and the lower temperature refrigerant flowing in from the second refrigerant relay portion through the second connection portion can be merged in the refrigerant relay portion, and these refrigerants can be mixed more efficiently, and the temperature of the refrigerant can be further reduced. As a result, the cooling performance of the heat exchanger can be further improved.

[0043] The second connection portion is a portion having the smallest flow path cross-sectional area on the refrigerant path from the refrigerant relay portion to the second refrigerant relay portion. The flow path cross-sectional area refers to the cross-sectional area of ​​the cross section in the refrigerant flow path that is perpendicular to the refrigerant flow.

[0044] The second connection part is preferably configured to connect the refrigerant relay part and the second refrigerant relay part at the shortest distance, similarly to the connection part. In this case, the increase in pressure loss associated with the reduction in the flow path cross-sectional area can be further suppressed while ensuring the cooling performance improvement effect formed by the second connection part.

[0045] The second refrigerant relay part is preferably configured to be farther from the cooling stave part than the refrigerant relay part. In this case, based on the same reasons as described above, the refrigerant relay part is configured to be farther from the cooling stave part than the refrigerant relay part, the cooling performance of the heat exchanger can be further improved.

[0046] The radiator may have a plurality of fin plates stacked on each other, and a refrigerant flow path may be formed between adjacent fin plates. In this case, the refrigerant flow path may be formed by a simple operation of stacking a plurality of fin plates. Therefore, the manufacturing cost of the radiator may be more easily reduced.

[0047] In a radiator having a plurality of fin plates, the flatness of the end surface of the radiator on the side having the refrigerant contact portion is preferably 0.2 mm or less. That is, when the entire end surface of the fin plate on the side having the refrigerant contact portion is sandwiched between two mutually parallel planes, the interval between the two planes is preferably 0.2 mm or less. In this case, when the cooling wall portion and the radiator are brazed, the solder can be more easily inserted between the cooling wall portion and the radiator, and the generation of joint defects such as gaps can be more effectively suppressed.

[0048] The flatness of the end surface of the radiator on the side with the refrigerant contact portion can be specifically measured by the following method. First, the radiator is placed on the surface plate so that the end surface on the side without the refrigerant contact portion of the pair of end surfaces in the lateral direction of the fin plate abuts against the surface plate. Then, the height of the end surface of the fin plate on the side with the refrigerant contact portion is measured at different positions using a height gauge. And the difference between the maximum height and the minimum height in the measurement results is taken as the flatness of the end surface of the radiator on the side with the refrigerant contact portion.

[0049] The heat sink may, for example, have a first fin plate and a second fin plate as the fin plate, and have a stacked structure in which the first fin plate and the second fin plate are alternately stacked. In such a heat sink, the following fin plate may be used as the first fin plate, the fin plate having a first reference surface portion; a first recessed portion that is recessed in a first direction in the stacking direction relative to the first reference surface portion; and a first protrusion that protrudes in a second direction, which is opposite to the first direction, relative to the first reference surface portion, and the first recessed portion and the first protrusion are alternately arranged in the transverse and longitudinal directions of the first fin plate. In addition, the following fin plate may be used as the second fin plate, the fin plate having a second reference surface portion; a second recessed portion that is recessed in the first direction relative to the second reference surface portion; and a second protrusion that protrudes in the second direction relative to the second reference surface portion, and the second recessed portion and the second protrusion are alternately arranged in the transverse and longitudinal directions of the second fin plate.

[0050] The above-mentioned “longitudinal direction of the fin plate” means the arrangement direction of the refrigerant inlet portion and the refrigerant outlet portion, and the “lateral direction of the fin plate” means a direction perpendicular to both the stacking direction and the longitudinal direction.

[0051] When the first fin plate and the second fin plate are stacked in such a manner that the first concave portion and the second convex portion are opposed to each other and the second concave portion and the first convex portion are opposed to each other, a refrigerant flow path including the space between the first concave portion and the second convex portion is formed on the side of the first fin plate where the first convex portion protrudes. In addition, a refrigerant flow path including the space between the second concave portion and the first convex portion can be formed on the side of the first fin plate where the first concave portion is recessed.

[0052] Therefore, the heat sink having the above-mentioned specific structure can reliably use the space formed between the adjacent fin plates as the refrigerant flow path. As a result, the contact area between the heat sink and the refrigerant can be further expanded, and the cooling performance can be further improved.

[0053] In the heat sink, a gap may be formed between the first convex portion and the second concave portion adjacent to the first convex portion in the second direction, or the first convex portion and the second concave portion may be in contact with each other. In addition, the first concave portion and the second convex portion may be joined by a joint such as a brazing joint. From the perspective of suppressing the formation of an unintended refrigerant path between the first fin plate and the second fin plate, it is preferred that the first convex portion and the second concave portion adjacent to the first convex portion in the second direction be in contact with each other, and it is more preferred that the first convex portion and the second concave portion be joined by a joint such as a brazing joint.

[0054] Similarly, a gap may be formed between the second convex portion and the first concave portion arranged on the first direction side of the second convex portion, or the second convex portion and the first concave portion may be in contact with each other. In addition, the second convex portion and the first concave portion may be joined by a joint such as a brazing joint. From the perspective of suppressing the formation of an unintended refrigerant path between the first fin plate and the second fin plate, it is preferred that the second convex portion and the first concave portion arranged on the first direction side of the second convex portion be in contact with each other, and it is more preferred that the second convex portion and the first concave portion be joined by a joint such as a brazing joint.

[0055] In the heat sink having the above-mentioned specific structure, it is preferred that the first reference surface portion is arranged at a portion surrounded by the first convex portion and the first concave portion, and the second reference surface portion is arranged at a portion surrounded by the second convex portion and the second concave portion. In this case, the above-mentioned refrigerant contact portion and refrigerant relay portion can be formed in the space between the first concave portion and the second convex portion and in the space between the second concave portion and the first convex portion, and a connecting portion can be formed between the first reference surface portion and the second reference surface portion. As a result, the refrigerant flow path can be formed more reliably.

[0056] The radiator may be mounted on a cooling wall portion of a heat exchanger. For example, a heat exchanger may include a cooling jacket having an outer wall portion including a cooling wall portion for cooling a heating element; an inner space surrounded by the outer wall portion; a refrigerant inlet that penetrates the outer wall portion and supplies refrigerant from the outside to the inner space; and a refrigerant outlet that discharges refrigerant from the inner space to the outside. By accommodating the radiator in the inner space of the cooling jacket, the cooling performance of the heat exchanger may be improved.

[0057] (Example)

[0058] (Implementation Method 1)

[0059] Reference Figure 1 to Figure 7 The heat sink 1 of this embodiment (see Figure 1 ) is used in a state where it is mounted on a cooling wall portion that cools the heat generating element in the heat exchanger. Figure 1 and Figure 3 As shown, the radiator 1 has a refrigerant flow path 2 through which the refrigerant flows. Figure 3 As shown, the refrigerant flow path 2 has a refrigerant inlet 21 for introducing refrigerant and a refrigerant outlet 22 for outlet refrigerant. In addition, a plurality of refrigerant contact portions 23, refrigerant relay portions 25, and connection portions 24 are provided on the refrigerant path from the refrigerant inlet 21 to the refrigerant outlet 22.

[0060] The refrigerant contacting parts 23 are configured to be arranged at intervals along the refrigerant path from the refrigerant inlet 21 to the refrigerant outlet 22, and to make the cooling wall part and the refrigerant contact. The refrigerant relaying part 25 is configured to be arranged between adjacent refrigerant contacting parts 23, and to be able to relay the refrigerant from the refrigerant contacting part 23 on the upstream side of the refrigerant path to the refrigerant contacting part 23 on the downstream side. Figure 3 and Figure 5 As shown, the connection portion 24 is located between the refrigerant relay portion 25 and the refrigerant contact portion 23 , and has a smaller flow path cross-sectional area than the refrigerant contact portion 23 and the refrigerant relay portion 25 .

[0061] The specific structure of the heat sink 1 of this embodiment will be described in more detail. Figure 1 and Figure 2 As shown, the heat sink 1 of this embodiment has a plurality of fin plates 3 (3a, 3b) stacked one on another, and a refrigerant flow path 2 is formed between adjacent fin plates 3. The outer dimension of the heat sink 1 in the stacking direction of the fin plates 3 is 54.4 mm.

[0062] As a material of the fin plate 3, for example, a metal with high thermal conductivity such as aluminum, aluminum alloy, copper, copper alloy, etc. can be used. Specifically, the fin plate 3 of this embodiment is composed of a so-called double-sided brazing plate in which a brazing material made of an Al-Si (aluminum-silicon) alloy is laminated on both sides of a core material made of aluminum or an aluminum alloy.

[0063] like Figure 6 and Figure 7 As shown, the fin plate 3 is rectangular in shape. In addition, the fin plate 3 of this embodiment is given concavoconvexity in the entire longitudinal direction X and the entire transverse direction Z, wherein the longitudinal direction X is the arrangement direction of the refrigerant inlet and the refrigerant outlet, and the transverse direction Z is a direction orthogonal to both the stacking direction Y of the fin plate 3 and the longitudinal direction X. The length and width of the fin plate 3 are not particularly limited. For example, the length of the fin plate 3 of this embodiment is 64 mm and the width is 8 mm.

[0064] The thickness of the fin plate 3 is preferably 0.6 to 1.5 mm. In this case, it is possible to achieve both reduction in pressure loss and improvement in cooling performance, and to more easily impart a concavo-convex shape to the fin plate 3. Specifically, the thickness of the fin plate 3 in this embodiment is 0.8 mm.

[0065] In the following, the side of the refrigerant inlet 21 in the longitudinal direction X of the fin plate 3 is referred to as "front X1", and the side of the refrigerant outlet 22 is referred to as "rear X2". In addition, the side of the fin plate 3 facing the cooling wall in the transverse direction Z is referred to as "upper Z1", and the opposite side of the upper side is referred to as "lower Z2". In addition, the expressions related to the above directions are only for convenience and have nothing to do with the directions when the radiator 1 is actually configured.

[0066] More specifically, the heat sink 1 of the present embodiment includes a first fin plate 3a and a second fin plate 3b as the fin plate 3. Figure 1 and Figure 2 As shown, in the heat sink 1 of the present embodiment, the first fin plates 3a and the second fin plates 3b are alternately stacked.

[0067] like Figure 5 and Figure 6 As shown, the first fin plate 3a has a first reference surface portion 31a in a flat plate shape, a first concave portion 32a that is recessed in a first direction Y1 in the stacking direction Y relative to the first reference surface portion 31a, and a first convex portion 33a that protrudes in a second direction Y2 that is opposite to the first direction Y1 relative to the first reference surface portion 31a. Figure 6 As shown, the first recessed portions 32a and the first protruding portions 33a are alternately arranged in the longitudinal direction X and the transverse direction Z of the first fin plate 3a.

[0068] More specifically, the first fin 3a of the present embodiment has three concave-convex rows, namely, an upper concave-convex row 34a in which the first concave portions 32a and the first convex portions 33a are alternately arranged along the upper side Z1 in the transverse direction Z, a lower concave-convex row 36a arranged along the lower side Z2, and a middle concave-convex row 35a arranged between the upper concave-convex row 34a and the lower concave-convex row 36a. The first concave portion 32a is arranged at the frontmost X1 of the upper concave-convex row 34a and the lower concave-convex row 36a, and the first convex portion 33a is arranged at the frontmost X1 of the middle concave-convex row 35a.

[0069] The first reference surface portion 31a is arranged in a portion surrounded by the first concave portion 32a and the first convex portion 33a when viewed from above in the stacking direction Y. Although not shown in the figure, the first reference surface portion 31a has a rectangular shape extending in a direction inclined at 45° with respect to the longitudinal direction X when viewed from above in the stacking direction Y.

[0070] When the thickness of the first fin plate 3a is t [mm], the first fin plate 3a is Figure 4 The outer dimension H [mm] in the stacking direction Y shown is preferably 1.0 ≤ H / t ≤ 7.0. In this case, it is possible to suppress molding defects, make the depth of the first recess 32a and the height of the first protrusion 33a sufficiently high, and further expand the heat transfer area. As a result, the cooling performance can be further improved. Specifically, the outer dimension H of the first fin plate 3a in the stacking direction Y of this embodiment is 1.7 mm.

[0071] like Figure 5 As shown in FIG. 1 , the bottom 321a of the first concave portion 32a, that is, the most depressed portion on the first direction Y1 side, is in the shape of a flat plate parallel to the first reference surface portion 31a. Figure 6 As shown, the bottom 321a of the first recess 32a arranged along the edge of the first fin plate 3a among the multiple first recesses 32a is shaped like a part of an octagon when viewed from above in the stacking direction Y, and the bottom 321a of the first recess 32a arranged closer to the inside of the edge of the first fin plate 3a is a complete octagon.

[0072] like Figure 4 As shown, the peripheral edge portion 322a of the bottom portion 321a is in a smooth curved surface shape and is connected to the peripheral edge portion 332a (described later) of the top portion 331a in the first protrusion 33a. Figure 4 The outer bending radius R of the peripheral portion 322a of the bottom 321a shown is preferably 1.0 to 3.0 mm. In this case, it is possible to suppress forming defects, and it is possible to achieve both a reduction in pressure loss and an improvement in cooling performance. The outer bending radius R of the peripheral portion 322a of the bottom 321a in the first fin plate 3a of this embodiment is specifically 1.3 mm.

[0073] The first convex portion 33a has a shape that is the inverted concave shape of the first concave portion 32a. Although not shown in the figure, the top 331a of the first convex portion 33a, that is, the most protruding portion on the second direction Y2 side, is in the shape of a flat plate parallel to the first reference surface portion 31a, similarly to the bottom 321a of the first concave portion 32a. Figure 6 As shown, the top 331a of the first protrusion 33a arranged along the edge of the first fin plate 3a among the multiple first protrusions 33a is shaped like a part of an octagon when viewed from above in the stacking direction Y, and the top 331a of the first protrusion 33a arranged closer to the inside of the edge of the first fin plate 3a is a complete octagon.

[0074] like Figure 4 As shown, the peripheral portion 332a of the top 331a is in a smooth curved surface shape and is connected to the peripheral portion 322a of the bottom 321a in the first recess 32a. Although not shown, the outer curvature radius of the peripheral portion 332a of the top 331a is the same as that of the bottom 321a of the first recess 32a, preferably 1.0 to 3.0 mm. The outer curvature radius of the peripheral portion 332a of the top 331a in the first fin plate 3a of this embodiment is specifically 1.3 mm.

[0075] Figure 4 The forming angle θ of the first fin plate 3a shown is preferably 30 to 60°. In this case, forming defects can be suppressed, and both the reduction of pressure loss and the improvement of cooling performance can be taken into account. Figure 4 As shown, the above-mentioned forming angle θ is specifically: on the cross section of the transverse Z passing through the center of the first recess 32a, the angle formed by the surface 333a at the top 331a of the first protrusion 33a in the second direction Y2 and the tangent 334a on the surface of the first fin plate 3a in the first direction Y1, passing through the boundary between the peripheral portion 322a of the first recess 32a and the peripheral portion 332a of the first protrusion 33a.

[0076] In addition, instead of the angle formed by the surface 333a and the tangent line 334a described above, the following angle may be set as the forming angle θ: the angle formed by the surface of the bottom 321a of the first recess 32a in the first direction Y1 and the tangent line on the surface of the first fin plate 3a in the second direction Y2 passing through the boundary between the peripheral edge 322a of the first recess 32a and the peripheral edge 332a of the first protrusion 33a on the cross section passing through the center of the first recess 32a in the horizontal direction Z. Specifically, the forming angle θ of the first fin plate 3a in this embodiment is 60°.

[0077] like Figure 5 and Figure 7As shown, the second fin plate 3b has a second reference surface 31b in a flat plate shape, a second concave portion 32b that is recessed in the first direction Y1 relative to the second reference surface 31b, and a second convex portion 33b that protrudes in the second direction Y2 relative to the second reference surface 31b. Figure 7 As shown, the second recessed portions 32b and the second protruding portions 33b are alternately arranged in the longitudinal direction X and the transverse direction Z of the second fin plate 3b.

[0078] More specifically, the second fin plate 3b of the present embodiment has a shape in which the concavoconvex of the first fin plate 3a is reversed. That is, the second fin plate 3b has three concavoconvex rows, namely, an upper concavoconvex row 34b in which the second concavoconvex portions 32b and the second convex portions 33b are alternately arranged along the upper side Z1 of the horizontal direction Z, a lower concavoconvex row 36b arranged along the lower side Z2, and a middle concavoconvex row 35b arranged between the upper concavoconvex row 34b and the lower concavoconvex row 36b. The second convex portion 33b is arranged at the frontmost X1 of the upper concavoconvex row 34b and the lower concavoconvex row 36b, and the second concavoconvex portion 32b is arranged at the frontmost X1 of the middle concavoconvex row 35b.

[0079] The second reference surface 31b is arranged in a portion surrounded by the second concave portion 32b and the second convex portion 33b when viewed from the stacking direction Y. Although not shown in the figure, the second reference surface 31b has a rectangular shape extending in a direction inclined at 45° with respect to the longitudinal direction X when viewed from the stacking direction Y.

[0080] As with the first fin plate 3a, when the thickness of the second fin plate 3b is t [mm], the second fin plate 3b has Figure 4 The outer dimension H [mm] in the stacking direction Y shown is preferably 1.0 ≤ H / t ≤ 7.0. In this case, it is possible to suppress molding defects, make the depth of the second recess 32b and the height of the second protrusion 33b sufficiently high, and further expand the heat transfer area. As a result, the cooling performance can be further improved. The outer dimension H of the second fin plate 3b in the stacking direction Y of this embodiment is specifically 1.7 mm.

[0081] Although not shown, the bottom 321b of the second recess 32b (see Figure 4 ), that is, the most depressed portion on the first direction Y1 side is in the shape of a flat plate parallel to the second reference surface portion 31b. Figure 7As shown, the bottom 321b of the second concave portion 32b is in a shape that forms a complete octagon or a part of an octagon when viewed from the stacking direction Y. Similarly to the bottom 321b of the second concave portion 32b, the top 331b of the second convex portion 33b, that is, the portion that protrudes most on the second direction Y2 side, is in a flat plate shape parallel to the second reference surface portion 31b, and is in a shape that forms a complete octagon or a part of an octagon when viewed from the stacking direction Y.

[0082] like Figure 4 As shown, the peripheral portion 322b of the bottom 321b in the second concave portion 32b and the peripheral portion 332b of the top 331b in the second convex portion 33b are in a smooth curved surface shape, and the peripheral portion 322b of the bottom 321b is connected to the peripheral portion 332b of the top 331b adjacent to the bottom. The outer bending radius R of the peripheral portion 322b of the bottom 321b and the peripheral portion 332b of the top 331b is preferably 1.0 to 3.0 mm. In this case, it is possible to suppress forming defects and take into account both the reduction of pressure loss and the improvement of cooling performance. The outer bending radius R of the peripheral portion 322b of the bottom 321b and the peripheral portion 332b of the top 331b in the second fin plate 3b of this embodiment is specifically 1.3 mm.

[0083] In addition, similarly to the first fin plate 3a, the forming angle θ of the concavo-convex shape in the second fin plate 3b is preferably 30 to 60°. In this case, forming defects can be suppressed, and both pressure loss reduction and cooling performance improvement can be achieved. Figure 4 As shown, the above-mentioned forming angle θ is specifically: on the cross section of the transverse Z passing through the center of the second recess 32b, the angle formed by the surface 323b in the first direction Y1 at the bottom 321b of the second recess 32b and the tangent 324b on the surface of the second fin plate 3b in the second direction Y2 passing through the peripheral portion 322b of the second recess 32b and the peripheral portion 332b of the second protrusion 33b.

[0084] In addition, instead of the angle formed by the surface 323b and the tangent line 324b described above, the following angle may be set as the forming angle θ: the angle formed by the surface of the top 331b of the second convex portion 33b in the second direction Y2 and the tangent line of the surface of the second fin plate 3b in the first direction Y1, passing through the boundary between the peripheral edge 322b of the second concave portion 32b and the peripheral edge 332b of the second convex portion 33b, on the cross section passing through the center of the second concave portion 32b in the lateral direction Z. Specifically, the forming angle θ of the second fin plate 3b in this embodiment is 60°.

[0085] In the heat sink 1 of this embodiment, Figure 4As shown, the first concave portion 32a of the first fin plate 3a is opposite to the second convex portion 33b of the second fin plate 3b adjacent to the first fin plate 3a, and the second concave portion 32b of the second fin plate 3b is opposite to the first convex portion 33a of the first fin plate 3a adjacent to the second fin plate 3b. Figure 4 As shown, the bottom 321a of the first recess 32a and the top 331b of the second protrusion 33b adjacent to the bottom 321a in the first direction Y1 are joined by a brazing joint 37, and the top 331a of the first protrusion 33a and the bottom 321b of the second recess 32b adjacent to the top 331a in the second direction Y2 are joined by a brazing joint 38.

[0086] Therefore, if Figure 3 and Figure 5 As shown, a refrigerant flow path 2 is formed between the first fin plate 3a and the second fin plate 3b adjacent to the first fin plate 3a in the second direction Y2, and the refrigerant flow path includes a space between the first recessed portion 32a and the second convex portion 33b, and a space between the first reference surface portion 31a and the second reference surface portion 31b. In addition, although not shown, a refrigerant flow path 2 is formed between the first fin plate 3a and the second fin plate 3b adjacent to the first fin plate 3a in the first direction Y1, and the refrigerant flow path includes a space between the second recessed portion 32b and the first convex portion 33a, and a space between the first reference surface portion 31a and the second reference surface portion 31b.

[0087] As described above, the refrigerant flow path 2 of this embodiment is formed between adjacent fin plates 3. Specifically, Figure 3 As shown, the refrigerant inlet portion 21 in the refrigerant flow path 2 of the present embodiment is composed of a space between a first recess 32a arranged along an edge in front of X1 of the first fin plate 3a and a second protrusion 33b adjacent to the first recess 32a in the second direction Y2, and a space between a first protrusion 33a arranged along an edge in front of X1 of the first fin plate 3a and a second protrusion 33b adjacent to the first protrusion 33a in the first direction Y1.

[0088] Specifically, the refrigerant outlet portion 22 of the present embodiment is composed of a space between a first recess 32a arranged along the edge X2 of the rear side of the first fin plate 3a and a second protrusion 33b adjacent to the first recess 32a in the second direction Y2, and a space between a first protrusion 33a arranged along the edge X2 of the rear side of the first fin plate 3a and a second protrusion 33b adjacent to the first protrusion 33a in the first direction Y1.

[0089] Specifically, the refrigerant contact portion 23 of the present embodiment is formed by the space between the upper concave-convex row 34a of the first fin plate 3a and the upper concave-convex row 34b of the second fin plate 3b. In addition, the refrigerant contact portion 23 is configured to be arranged on the end surface of the upper Z1 of the radiator 1, and can directly supply refrigerant to the cooling wall portion.

[0090] The refrigerant contact portion 23 in each refrigerant flow path 2 may be arranged, for example, to satisfy the following formula (1). l is the distance between the refrigerant contact parts 23 in the longitudinal direction X (see Figure 3 ), L is the dimension of the heat sink 1 in the longitudinal direction X, and n is a natural number.

[0091] nλ l / 2=L (1)

[0092] The pitch λ of the refrigerant contact portion 23 of this embodiment l Specifically, it is 8.0 mm. The refrigerant contact portion 23 of the present embodiment is arranged so as to satisfy the above-mentioned formula (1) when the value of n is 16.

[0093] The refrigerant relay portion 25 of the present embodiment is arranged to be farther from the cooling wall portion in the downward direction Z2 than the refrigerant contact portion 23. Figure 5 As shown, the refrigerant relay portion 25 is a space between the middle-layer concave-convex row 35a of the first fin plate 3a and the middle-layer concave-convex row 35b of the second fin plate 3b.

[0094] Specifically, Figure 5 As shown, the connection portion 24 of the present embodiment includes a space between a first reference surface portion 31a and a second reference surface portion 31b, wherein the first reference surface portion exists between the upper concave-convex row 34a and the middle concave-convex row 35a in the first fin plate 3a, and the second reference surface portion exists between the upper concave-convex row 34b and the middle concave-convex row 35b in the second fin plate 3b. The connection portion 24 of the present embodiment connects the refrigerant contact portion 23 and the refrigerant relay portion 25 in a straight line, that is, at the shortest distance.

[0095] The connection portion 24 preferably extends in a direction inclined relative to the longitudinal direction X of the fin plate 3. In this case, the pressure loss during the flow of the refrigerant can be further reduced while maintaining the cooling performance. From the perspective of both high cooling performance and low pressure loss, the inclination of the extension direction of the connection portion 24 relative to the longitudinal direction X is preferably 20 to 70°, more preferably 30 to 60°, and further preferably 40 to 50°. Specifically, the connection portion 24 of the present embodiment extends in a direction inclined 45° relative to the longitudinal direction X of the fin plate 3.

[0096] In addition, the refrigerant flow path 2 of the present embodiment also has: a second refrigerant relay portion 27, which is arranged between adjacent refrigerant relay portions 25 and relays the refrigerant from the refrigerant relay portion 25 on the upstream side of the refrigerant path to the refrigerant relay portion 25 on the downstream side; and a second connecting portion 26, which is located between the second refrigerant relay portion 27 and the refrigerant relay portion 25 and has a smaller flow path cross-sectional area than the refrigerant relay portion 25 and the second refrigerant relay portion 27.

[0097] Specifically, Figure 5 As shown, the second refrigerant relay portion 27 of the present embodiment is a space between the lower concave-convex row 36a of the first fin plate 3a and the lower concave-convex row 36b of the second fin plate 3b.

[0098] Specifically, Figure 5 As shown, the second connection portion 26 of the present embodiment includes a space between a first reference surface portion 31a and a second reference surface portion 31b, wherein the first reference surface portion exists between the middle concave-convex row 35a and the lower concave-convex row 36a in the first fin plate 3a, and the second reference surface portion exists between the upper concave-convex row 34b and the middle concave-convex row 35b in the second fin plate 3b. The second connection portion 26 of the present embodiment connects the refrigerant relay portion 25 and the second refrigerant relay portion 27 in a straight line, that is, at the shortest distance.

[0099] As with the connection portion 24, the second connection portion 26 preferably extends in a direction inclined relative to the longitudinal direction X of the fin plate 3. In this case, the pressure loss during the flow of the refrigerant can be further reduced while maintaining the cooling performance. From the perspective of both high cooling performance and low pressure loss, the inclination of the extension direction of the second connection portion 26 relative to the longitudinal direction X is preferably 20 to 70°, more preferably 30 to 60°, and further preferably 40 to 50°. Specifically, the second connection portion 26 of the present embodiment extends in a direction inclined 45° relative to the longitudinal direction X of the fin plate 3.

[0100] The heat sink 1 of the present embodiment has a refrigerant flow path 2, which includes: a plurality of refrigerant contact portions 23 disposed between a refrigerant inlet portion 21 and a refrigerant outlet portion 22; a refrigerant relay portion 25 that relays the refrigerant from the refrigerant contact portion 23 on the upstream side of the refrigerant path to the refrigerant contact portion 23 on the downstream side; and a connecting portion 24 located between the refrigerant relay portion 25 and the refrigerant contact portion 23. In addition, the connecting portion 24 has a smaller flow path cross-sectional area than the refrigerant contact portion 23 and the refrigerant relay portion 25.

[0101] The refrigerant flow in the refrigerant flow path 2 of the radiator 1 of the present embodiment is, for example, as follows. The refrigerant flowing into the flow path from the refrigerant inlet portion 21 is guided from the refrigerant inlet portion 21 to the refrigerant contact portion 23. Moreover, the refrigerant that performs heat exchange with the cooling wall portion of the heat exchanger, etc. in the refrigerant contact portion 23 flows into the refrigerant relay portion 25 through the connection portion 24. Since the flow path cross-sectional area of ​​the connection portion 24 is smaller than the flow path cross-sectional areas of the refrigerant contact portion 23 and the refrigerant relay portion 25, the refrigerant flowing into the refrigerant relay portion 25 is stirred by the expansion and contraction of the flow path. In addition, the refrigerant flowing from the refrigerant relay portion 25 through the connection portion 24 into the refrigerant contact portion 23 is also stirred by the difference in flow path cross-sectional areas between the connection portion 24 and the refrigerant contact portion 23 and the refrigerant relay portion 25 in the same manner as described above.

[0102] Therefore, in the radiator 1, by providing the connection portion 24 between the refrigerant contact portion 23 and the refrigerant relay portion 25, the refrigerant flowing in the refrigerant flow path 2 can be efficiently stirred, and the unevenness of the temperature of the refrigerant in the refrigerant flow path 2 can be reduced. As a result, the temperature difference between the refrigerant in contact with the radiator 1 and the radiator 1 can be further increased. As a result, the cooling performance of the heat exchanger can be improved.

[0103] In addition, the refrigerant flow path 2 has: a second refrigerant relay portion 27, which is arranged between adjacent refrigerant relay portions 25 and relays the refrigerant from the refrigerant relay portion 25 on the upstream side of the refrigerant path to the refrigerant relay portion 25 on the downstream side; and a second connecting portion 26, which is located between the second refrigerant relay portion 27 and the refrigerant relay portion 25 and has a smaller flow path cross-sectional area than the refrigerant relay portion 25 and the second refrigerant relay portion 27. Therefore, in the second refrigerant relay portion 27, the refrigerant can be stirred in the same manner as in the refrigerant contact portion 23. Furthermore, in the refrigerant relay portion 25, the refrigerant flow flowing in from the refrigerant contact portion 23 through the connecting portion 24 and the refrigerant flow flowing in from the second refrigerant relay portion 27 through the second connecting portion 26 are merged, so that the refrigerant can be stirred more effectively. As a result, the cooling performance of the heat exchanger can be further improved.

[0104] In addition, the peripheral edge 322a of the first concave portion 32a, the peripheral edge 332a of the first convex portion 33a, the peripheral edge 322b of the second concave portion 32b, and the peripheral edge 332b of the second convex portion 33b of the present embodiment are all composed of smooth curved surfaces. Therefore, at any position of the refrigerant flow path 2, the inner surface of the radiator 1 is inclined relative to the surface orthogonal to the refrigerant flow direction. That is, the inner surface of the radiator 1 of the present embodiment does not have a surface orthogonal to the refrigerant flow direction.

[0105] Thus, by configuring the radiator 1 so that the inner surface of the radiator does not have a surface perpendicular to the refrigerant flow direction, the refrigerant flow resistance can be further reduced. As a result, the pressure loss can be further reduced.

[0106] (Implementation Method 2)

[0107] In this embodiment, a fin plate 302 having a different range of concavoconvex shapes is described. In the embodiments after this embodiment, the same reference numerals as those in the previous embodiment indicate the same components as those in the previous embodiment unless otherwise specified.

[0108] Although in embodiment 1, the first fin plate 3a and the second fin plate 3b are shown in which the recesses 32 (first recess 32a, second recess 32b) and the protrusions 33 (first protrusion 33a, second protrusion 33b) are provided in the entire longitudinal direction X and the lateral direction Z, the recesses 32 and the protrusions 33 may also be provided in a part of the fin plate 3.

[0109] For example, Figure 8 As shown, the recess 32 and the protrusion 33 may be provided in a portion of the longitudinal direction X of the fin plate 302. For example, by providing the recess 32 and the protrusion 33 just below the predetermined installation position of the heating element, it is possible to suppress the increase in pressure loss caused by the recessed and convex shapes while ensuring sufficient cooling performance.

[0110] (Implementation method 3)

[0111] In this embodiment, another embodiment of the fin plate 303 in which the range of the concave-convex shape is changed will be described. Fig. 9 As shown, the concave portion 32 and the convex portion 33 may be provided in a portion of the fin plate 303 in the lateral direction Z. In this case, the cooling performance can be improved by the concave-convex shape, and an increase in pressure loss due to the concave-convex shape can be suppressed.

[0112] (Implementation 4)

[0113] In this embodiment, the heat exchanger 4 including the radiator 1 is described. Figures 10-12 As shown, the heat exchanger 4 has a radiator 1 and a cooling jacket 5. Fig.10 and Fig.12As shown, the cooling jacket 5 has: an outer wall portion 52, which includes a cooling wall portion 51 for cooling the heating element; an inner space 53, which is surrounded by the outer wall portion 52; a refrigerant inlet 54, which penetrates the outer wall portion 52 and supplies refrigerant to the inner space 53 from the outside of the heat exchanger 4; and a refrigerant outlet 55, which discharges the refrigerant from the inner space 53 to the outside of the heat exchanger 4. The radiator 1 is accommodated in the inner space 53 of the cooling jacket 5.

[0114] like Fig.10 and 11 As shown, the outer wall portion 52 of the cooling jacket 5 has a substantially rectangular cover portion 56 and a cup portion 57 placed on the cover portion 56. Fig.10 and Fig.12 As shown, the cup portion 57 has: a cooling wall portion 51, which is opposite to the cover portion 56 and has a substantially rectangular shape; a side wall portion 571, which extends from the outer peripheral edge of the cooling wall portion 51 to the cover portion 56 side; and a flange portion 572, which is formed at the front end of the side wall portion 571 and is joined to the cover portion 56. In addition, the cover portion 56 and the flange portion 572 can be joined by methods such as brazing, welding, and stir friction welding.

[0115] The refrigerant inlet 54 and the refrigerant outlet 55 are provided in the center of a pair of short sides in the outer peripheral edge portion of the cooling stave portion 51 .

[0116] like Fig.12 As shown, the radiator 1 is arranged in the internal space 53 of the cooling wall portion 51 surrounded by the cover portion 56 and the cup portion 57. The radiator 1 is arranged so that the refrigerant inlet 21 of the refrigerant flow path 2 faces the refrigerant inlet 54 of the cooling jacket 5 and the refrigerant outlet 22 faces the refrigerant outlet 55.

[0117] like Fig.12 As shown, in the present embodiment, both end surfaces 34 ( 341 , 342 ) of the fin plate 3 in the transverse direction Z are joined to the inner surface of the cooling stave portion 51 or the inner surface of the cover portion 56 by brazing.

[0118] When the heat sink 1 having a plurality of fin plates 3 is brazed to the cooling jacket 5 as in the present embodiment, it is preferred that the flatness of the end surface of the heat sink 1 on the side having the refrigerant contact portion 23 and the flatness of the end surface of the heat sink 1 on the side not having the refrigerant contact portion 23 be 0.2 mm or less. In this case, when the cooling jacket 5 and the heat sink 1 are brazed, the solder can be more easily introduced between the cooling jacket 5 and the heat sink 1, and the generation of bonding defects such as voids can be more effectively suppressed.

[0119] The flatness of the end surface of the radiator 1 on the side not having the refrigerant contact portion 23 can be measured by the same method as the flatness of the end surface of the radiator 1 on the side having the refrigerant contact portion 23. That is, the radiator 1 is placed on the surface plate so that the end surface 341 on the side having the refrigerant contact portion 23 of the pair of end surfaces 34 in the lateral direction Z of the fin plate 3 abuts against the surface plate. Then, the height of the end surface 342 on the side not having the refrigerant contact portion 23 of the fin plate is measured at different positions using a height gauge. And the difference between the maximum height and the minimum height in the measurement results is taken as the flatness of the end surface of the radiator 1 on the side not having the refrigerant contact portion 23.

[0120] Since the heat exchanger 4 of the present embodiment has the above-mentioned structure, the refrigerant flowing into the internal space 53 from the refrigerant inlet 54 can be guided into the refrigerant flow path 2 through the refrigerant introduction portion 21 of the radiator 1. In addition, as described above, the refrigerant in the refrigerant flow path 2 can exchange heat with the cooling wall portion 51 at the refrigerant contact portion 23 while being stirred by the refrigerant relay portion 25, the connection portion 24, the second refrigerant relay portion 27, and the second connection portion 26. Moreover, the refrigerant reaching the refrigerant outlet portion 22 is discharged from the refrigerant outlet 55. Therefore, the heat generating body mounted on the outer surface of the cooling wall portion 51 can be efficiently cooled.

[0121] (Comparison method 1)

[0122] In this embodiment, a heat sink 9 is described in which a plurality of grid-shaped plates 91 (91a, 91b) are stacked, wherein the plates have a plurality of longitudinal ribs 911 (911a, 911b) extending in the longitudinal direction, a plurality of transverse ribs 912 (912a, 912b) orthogonal to the longitudinal ribs 911, and a plurality of slits 913 defined by the longitudinal ribs 911 and the transverse ribs 912. Figures 13-15 As shown, the heat sink 9 of this embodiment has: a first plate 91a having a plurality of slits 913a extending in the longitudinal direction; and a second plate 91b in which the positions of the slits 913b in the longitudinal direction are offset from the slits 913a of the first plate 91a by half the pitch of the slits 913, and the first plate 91a and the second plate 91b are alternately stacked. Fig.15 As shown, the refrigerant flow path of the heat sink 9 of the present embodiment is constituted by the slits 913a of the first plate 91a and the slits 913b of the second plate 91b.

[0123] Specifically, the heat sink 9 of the present embodiment has external dimensions of 64 mm in length, 54.2 mm in width, and 8 mm in thickness. The thickness of the plate 91 is 1.0 mm. In addition, the width of the longitudinal ribs 911 of the plate 91 is 1.0 mm, and the interval between the longitudinal ribs 911 (i.e., the width of the slit 913) is 0.90 mm. In addition, the width of the transverse ribs 912 of the plate 91 is 2.0 mm, and the interval between the transverse ribs 912 (i.e., the length of the slit 913) is 5.75 mm.

[0124] The cooling performance and pressure loss of the radiator according to the first embodiment and the radiator 9 according to the first comparative embodiment can be compared by, for example, the following thermal fluid simulation.

[0125] First, a structural model is prepared in which an aluminum plate as a cooling wall portion 51 is placed on the radiator 1, 9. A heating element with a calorific value of 1650 W is arranged on the cooling wall portion 51. Then, a long-acting coolant as a refrigerant is supplied to the refrigerant flow path of the radiator 1, 9 at different flow rates, and the thermal resistance and pressure loss (i.e., the difference between the pressure of the refrigerant at the inlet of the refrigerant flow path and the pressure of the refrigerant at the outlet) between the heating element and the refrigerant are calculated when the temperature of the heating element reaches a stable state.

[0126] Fig.16 A graph showing the relationship between the thermal resistance and the pressure loss in the heat sink 1 of the first embodiment and the heat sink 9 of the first comparative embodiment is shown. Fig.16 The vertical axis is the ratio of thermal resistance based on the thermal resistance value when the refrigerant flow rate is 6 L / min in the radiator 9 of comparison method 1, and the horizontal axis is the ratio of pressure loss based on the pressure loss value when the refrigerant flow rate is 6 L / min in the radiator 9 of comparison method 1.

[0127] like Fig.16 As shown, the heat sink 1 of the first embodiment can achieve the same thermal resistance as the heat sink 9 of the first comparative embodiment with lower pressure loss than the heat sink 9 of the first comparative embodiment. The results show that the heat sink 1 of the first embodiment can improve cooling performance and reduce pressure loss.

[0128] The specific form of the heat sink according to the present invention is not limited to the forms shown in Embodiments 1 to 3, and the structure can be appropriately changed within the scope that does not damage the gist of the present invention. For example, the bottom of the first concave part and the second concave part, and the top of the first convex part and the second convex part can also be a circle, an ellipse, a quadrilateral, a hexagon, or a shape that forms a part of these shapes.

[0129] In addition, although in embodiments 1 to 3, the bottom of the first concave portion and the second concave portion and the top of the first convex portion and the second convex portion are shown to be flat-plate-shaped, the first concave portion, the second concave portion, the first convex portion and the second convex portion can be a shape such as a hemispherical shape without a flat-plate bottom and top.

[0130] The first fin plate 3a and the second fin plate 3b may be joined to each other by brazing as shown in Embodiments 1 to 3, or may be held by a connecting member that intersects with and connects the plurality of fin plates, for example.

[0131] In addition, although in Embodiments 1 to 3, each fin plate has three concave-convex rows, namely, an upper concave-convex row, a middle concave-convex row, and a lower concave-convex row, each fin plate may have four or more concave-convex rows. The concave-convex rows may be arranged, for example, in a manner satisfying the following formula (2). However, λ in the following formula (2) h is the spacing of the concave and convex columns in the horizontal direction Z, h is the size of the heat sink in the horizontal direction Z, and m is a natural number.

[0132] mλ h / 2=h (2)

Claims

1. A radiator configured to be mounted on a cooling wall portion for cooling a heat generating element in a heat exchanger, wherein the radiator has a refrigerant flow path configured to allow refrigerant to flow through the refrigerant, The refrigerant flow path has: A refrigerant introduction part for introducing refrigerant; A refrigerant outlet portion for outlet the refrigerant; A plurality of refrigerant contact portions are arranged at intervals from each other along a refrigerant path from the refrigerant inlet portion to the refrigerant outlet portion so as to bring the cooling wall portion into contact with the refrigerant; a refrigerant relay portion disposed between adjacent refrigerant contact portions and relaying the refrigerant from the refrigerant contact portion on the upstream side to the refrigerant contact portion on the downstream side in the refrigerant path; as well as a connecting portion, located between the refrigerant relay portion and the refrigerant contact portion, and having a flow path cross-sectional area smaller than the flow path cross-sectional area of ​​the refrigerant contact portion and the flow path cross-sectional area of ​​the refrigerant relay portion, The radiator includes a plurality of fin plates stacked on each other, and the refrigerant flow path is formed between adjacent fin plates.

2. The heat sink according to claim 1, wherein: The refrigerant relay portion is arranged farther from the cooling stave portion than the refrigerant contact portion.

3. The radiator according to claim 1 or 2, wherein: The refrigerant flow path comprises: a second refrigerant relay part, which is arranged between adjacent refrigerant relay parts and relays the refrigerant from the refrigerant relay part on the upstream side of the refrigerant path to the refrigerant relay part on the downstream side; and a second connecting part, which is located between the second refrigerant relay part and the refrigerant relay part, and the flow path cross-sectional area of ​​the second connecting part is smaller than the flow path cross-sectional area of ​​the refrigerant relay part and the flow path cross-sectional area of ​​the second refrigerant relay part.

4. The heat sink according to claim 1, wherein: The heat sink has a first fin plate and a second fin plate as the fin plate, and the first fin plate and the second fin plate are alternately stacked. The first fin plate has: A first reference face; a first recessed portion recessed in a first direction in the stacking direction relative to the first reference surface portion; and The first convex portion protrudes in a second direction opposite to the first direction relative to the first reference surface portion. Furthermore, the first concave portions and the first convex portions are alternately arranged in the transverse direction and the longitudinal direction of the first fin plate. The second fin plate has: A second reference face; a second recessed portion recessed toward the first direction relative to the second reference surface portion; and a second convex portion protruding in the second direction relative to the second reference surface portion; Furthermore, the second concave portions and the second convex portions are alternately arranged in the transverse direction and the longitudinal direction of the second fin plate. The first concave portion and the second convex portion are opposite to each other, The second concave portion is opposite to the first convex portion.

5. The heat sink according to claim 4, wherein: The first reference surface portion is arranged at a portion surrounded by the first convex portion and the first concave portion, and the second reference surface portion is arranged at a portion surrounded by the second convex portion and the second concave portion.

6. A heat exchanger comprising the radiator according to any one of claims 1 to 5, wherein the heat exchanger has a cooling jacket. The cooling jacket comprises: an outer wall portion including a cooling wall portion for cooling a heating element; an inner space surrounded by the outer wall portion; a refrigerant inlet that penetrates the outer wall portion and supplies refrigerant from the outside of the heat exchanger to the inner space; and a refrigerant outlet that discharges refrigerant from the inner space to the outside of the heat exchanger. The radiator is accommodated in the inner space of the cooling jacket.

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