Heat sink and method for manufacturing the same

Abstract

According to the present invention, the distribution direction (Z) of a cooling liquid introduced into a heat sink (100) is orthogonal to a lamination direction (Y). A plurality of holes (150) are formed in each plate (80). When the plates (80) are laminated in the lamination direction (Y), the holes (150) of the plates (80) become connected to each other in the lamination direction (Y) and the distribution direction (Z) to form flow paths (800) formed spirally in the distribution direction ( Z). Only a single line of a spiral center axis (13) at the spiral center of each of the flow paths (800) is formed in the lamination direction (Y).

Description

[Technical field]

[0001] The present application relates to a heat sink and a method for manufacturing a heat sink. [Background technology]

[0002] Among conventional heat sinks, there is a liquid-cooled type that cools the heat generating element by cooling the main body with which the heat generating element to be cooled is in contact with a refrigerant. In such a liquid-cooled heat sink, a flow path is formed inside the main body to allow the refrigerant to flow. For example, Patent Document 1 discloses a heat sink that is composed of a laminate of a flat first plate and a second plate formed by stamping a metal plate, and both plates are integrally formed with a large number of elongated vertical members that are arranged parallel to each other and spaced apart in a direction perpendicular to the flow direction of the cooling liquid, and are positioned in the flow direction of the cooling liquid, and diagonal members that connect adjacent vertical members diagonally, and the respective vertical members of both plates are aligned and overlapped, and the respective diagonal members are arranged spaced apart from each other in the flow direction and are arranged in opposite directions to each other. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-114174 A Summary of the Invention [Problem to be solved by the invention]

[0004] In conventional heat sinks and methods for manufacturing heat sinks, the coolant meanders regularly along the flow path and rotates in a spiral to promote heat transfer. In conventional configurations, multiple rows of spirally rotating flows are generated in the stacking direction. Heat generated by a heat generating element (object to be cooled) placed in the top layer of the stacked plates is transferred to the stacked plates and dissipated into the coolant. The temperature of the plate closest to the heat generating element is the highest, and the temperature of the plate decreases the further away from the heat generating element.

[0005] The greater the temperature difference between the plate and the coolant, the greater the amount of heat dissipated from the plate; therefore, near the heat generating element, a large amount of heat is dissipated to the coolant by a locally generated spirally rotating flow, while in areas far from the heat generating element, a smaller amount of heat is dissipated compared to near the heat generating element by a spirally rotating flow that exists in a different row from the aforementioned spirally rotating flow.

[0006] Therefore, the cooling liquid in the area close to the heat generating element becomes hot, and the cooling liquid in the area far from the heat generating element becomes cold. However, there was a problem that the heat dissipation efficiency decreases when the temperature of the cooling liquid becomes high in a concentrated manner in the area close to the heat generating element where the temperature difference between the plate temperature and the cooling liquid is greatest.

[0007] Furthermore, because the heat to be dissipated into the coolant is conducted within the metal before reaching the coolant, the larger the cross-sectional area of ​​the heat path within the metal, the easier it is to transmit heat to a location farther away from the heat source, and the higher the heat dissipation performance.However, if the cross-sectional area of ​​the heat path within the metal is increased, there is a problem in that it is difficult to increase the contact area between the coolant and the metal, i.e., the heat dissipation area, and this reduces the heat dissipation efficiency.

[0008] Furthermore, the areas where adjacent plates are in contact are limited, and there are gaps, which increases the heat dissipation area, but the cross-sectional area of ​​the heat conduction path within the metal is narrow, making it difficult to conduct heat to areas far from the heating element, resulting in reduced heat dissipation efficiency.

[0009] The present application discloses a technique for solving the above-mentioned problems, and has an object to provide a heat sink capable of improving heat dissipation efficiency and a method for manufacturing the heat sink. [Means for solving the problem]

[0010] The heat sink disclosed in the present application comprises: In a heat sink having a fin portion in which a plurality of plates are stacked in a stacking direction, A flow direction of the cooling liquid introduced into the heat sink is perpendicular to the stacking direction, Each of the plates has a plurality of holes formed therein, When the plates are stacked in the stacking direction, the holes of the plates are connected to each other in the stacking direction and the flow direction to form a flow path that is formed in a spiral shape toward the flow direction, The spiral central axes of the flow paths are formed in only one row in the stacking direction. Further, the present invention discloses a method for manufacturing a heat sink, comprising the steps of: a first step of forming a plurality of said holes in each of said plates; and a second step of stacking the plates in the stacking direction so that the holes in the plates are connected in the stacking direction and the flow direction to form a spiral flow path in the flow direction. Effect of the Invention

[0011] According to the heat sink and the method for manufacturing the heat sink disclosed in the present application, The heat dissipation efficiency of the heat sink can be improved. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1A is a perspective view showing the configuration of a heat sink according to a first embodiment, and FIG. 1B is a cross-sectional view showing the configuration of the heat sink shown in FIG. 1A. [Diagram 2] 2A is a front view of the heat sink shown in FIG. 1 with the base portion, fin portion, and heating element mounted thereon, and FIG. 2B is an enlarged side view of the heat sink shown in FIG. 3A with the base portion, fin portion, and heating element mounted thereon, as viewed from the side indicated by arrow K. [Diagram 3] 3 is an exploded perspective view showing the configuration of a base portion and a fin portion of the heat sink shown in FIG. 2 and a heating element mounted thereon. [Figure 4] 3 is a perspective view showing the base portion and the fin portion of the heat sink shown in FIG. 2 with the fin portion facing upward. [Diagram 5] 5A is an enlarged top view showing the configuration of the plates constituting the fin portion of the heat sink shown in FIG. 4; FIG. 5B is an enlarged top view showing the configuration of the plates constituting the fin portion of the heat sink shown in FIG. 4; FIG. 5C is an enlarged top view showing the configuration of the plates constituting the fin portion of the heat sink shown in FIG. 4; FIG. 5D is an enlarged top view showing the configuration of the plates constituting the fin portion of the heat sink shown in FIG. 4; FIG. 5E is an enlarged top view showing the configuration of the plates constituting the fin portion of the heat sink shown in FIG. 4; FIG. 5F is an enlarged top view showing the configuration of the plates constituting the fin portion of the heat sink shown in FIG. 4; FIG. 5G is an enlarged top view showing the configuration of the plates constituting the fin portion of the heat sink shown in FIG. 4; FIG. 5H is an enlarged top view showing the configuration of the plates constituting the fin portion of the heat sink shown in FIG. 4; and FIG. 5I is an enlarged top view showing the configuration of the plates constituting the fin portion of the heat sink shown in FIG. 4. [Figure 6] 3 is a front view of the heat sink shown in FIG. 2 with a base portion and a fin portion extracted. [Figure 7] 7A is a cross-sectional view of the base portion and fin portion shown in FIG. 6 along line KA-KA, FIG. 7B is a cross-sectional view of the base portion and fin portion shown in FIG. 6 along line KB-KB, FIG. 7C is a cross-sectional view of the base portion and fin portion shown in FIG. 6 along line KC-KC, FIG. 7D is a cross-sectional view of the base portion and fin portion shown in FIG. 6 along line KD-KD, and FIG. 7E is a cross-sectional view of the base portion and fin portion shown in FIG. 6 along line KE-KE. [Figure 8] Figure 8A is an enlarged view showing a portion of the configuration of the fin portion shown in Figure 7A, Figure 8B is an enlarged view showing a portion of the configuration of the fin portion shown in Figure 7B, Figure 8C is an enlarged view showing a portion of the configuration shown in Figure 7C, Figure 8D is an enlarged view showing a portion of the configuration shown in Figure 7D, and Figure 8E is an enlarged view showing a portion of the configuration shown in Figure 7E. [Figure 9] 2 is a diagram showing the flow of the coolant inside a flow path formed by connecting holes in the plates of the heat sink shown in FIG. 1. FIG. [Figure 10] This is a contour diagram showing the flow lines of the coolant in the heat sink shown in Figure 1, derived by a three-dimensional fluid simulation, with shading according to the flow velocity. [Figure 11] FIG. 11A is a plan view of a base portion of a heat sink according to embodiment 2 and a heating element mounted thereon, and FIG. 11B is an enlarged left side view of the base portion and fin portion of the heat sink shown in FIG. 11A and the heating element mounted thereon. [Figure 12] FIG. 12A is a plan view showing a configuration of a plate of a heat sink according to embodiment 3, and FIG. 12B is an enlarged plan view of a portion enclosed by a dashed line shown in FIG. 12A. [Figure 13] FIG. 11 is a side view of a plate of a heat sink according to a third embodiment. [Figure 14] FIG. 14A is a plan view showing the configuration of a fin member of a heat sink according to embodiment 5, and FIG. 14B is a plan view showing the configuration of a fin portion cut out from FIG. 14A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] In the following description, the same or equivalent parts in the drawings are given the same reference numerals and their description will be omitted as appropriate. Also, the directions in the heat sink are indicated as the stacking direction Y, the direction in which the plates described below are stacked, the flow direction Z, which is perpendicular to the stacking direction Y and in which the cooling liquid flows, and the direction perpendicular to the stacking direction Y and the flow direction Z, respectively. Therefore, in the parts that constitute the heat sink, each direction will be described based on these directions. Also, since this is the same in all the following embodiments, the description will be omitted as appropriate.

[0014] Embodiment 1 Fig. 1A is a perspective view showing the configuration of a heat sink according to embodiment 1. Fig. 1B is a cross-sectional view showing the configuration of the heat sink shown in Fig. 1A. Fig. 2A is a front view showing the configuration of the base part, fin part, and heating element mounted thereon of the heat sink shown in Fig. 1. Fig. 2B is a side view showing the configuration of the base part, fin part, and heating element mounted thereon of the heat sink shown in Fig. 2A, as viewed from the side indicated by arrow K.

[0015] Fig. 3 is an exploded perspective view of the base, fins, and heating element of the heat sink shown in Fig. 2. Fig. 4 is a perspective view showing the fins of the heat sink shown in Fig. 2 facing upward. Figs. 5A to 5I are top views of the plates constituting the fins shown in Fig. 5. Fig. 6 is a front view showing the configuration of the heat sink shown in Fig. 1 with the base and fins extracted.

[0016] FIG. 7A is a KA-KA line cross-sectional view of the base portion and the fin portion shown in FIG. 6. FIG. 7B is a KB-KB line cross-sectional view of the base portion and the fin portion shown in FIG. 6. FIG. 7C is a KC-KC line cross-sectional view of the base portion and the fin portion shown in FIG. 6. FIG. 7D is a KD-KD line cross-sectional view of the base portion and the fin portion shown in FIG. 6. FIG. 7E is a KE-KE line cross-sectional view of the base portion and the fin portion shown in FIG. 6. FIG. 8A is an enlarged view showing the configuration of a portion 810 of the flow path cross section shown in FIG. 7A. FIG. 8B is an enlarged view showing the configuration of a portion 811 of the flow path cross section shown in FIG. 7B. FIG. 8C is an enlarged view showing the configuration of a portion 812 of the flow path cross section shown in FIG. 7C. FIG. 8D is an enlarged view showing the configuration of a portion 813 of the flow path cross section shown in FIG. 7D. FIG. 8E is an enlarged view showing the configuration of a portion 814 of the flow path cross section shown in FIG. 7E.

[0017] Figure 9 is a diagram showing the flow of the coolant inside the flow passage formed by connecting the holes in the plates of the heat sink shown in Figure 1. Figure 10 is a contour diagram showing the streamlines of the flow of the coolant in the heat sink shown in Figure 1, derived by a three-dimensional fluid simulation, with shading according to the flow speed.

[0018] 1 and 2, the heat sink 100 according to the first embodiment is constructed by incorporating a base portion 1, which has a heating element 2 mounted on one surface and a fin portion 8 having a flow path 800 (see FIG. 8) described below on the surface opposite the heating element 2, into a water jacket 7. Watertightness between the base portion 1 and the water jacket 7 is maintained by placing the base portion 1 on the water jacket 7 via an O-ring 17, pressing the base portion 1 against the water jacket 7 with a fastening plate 3 and fastening it with bolts 4.

[0019] A supply channel 5 for supplying the cooling liquid and a discharge channel 6 for discharging the cooling liquid are connected to the water jacket 7. The cooling liquid flows in from the supply channel 5, passes through a channel inlet 9 (FIG. 2B) into the channel 800 of the fin portion 8, and is discharged from the discharge channel 6.

[0020] As shown in Figures 3, 4, and 5, by stacking plates 81, 82, 83, 84, 85, 86, 87, 88, and 89 (hereinafter referred to as plates 81-89 when referring to all of these plates and referred to as plate 80 when referring to any one of the plates) having holes 151, 152, 153, 154, 155, 156, 157, 158, and 159 (hereinafter referred to as holes 151-159 when referring to all of these holes, and referred to as hole 150 when referring to any one of the holes) with different patterns, certain holes 150 are connected in the stacking direction Y and the flow direction Z, and a flow path 800 in the fin section 8 is formed.

[0021] The flow paths 800 will be described with reference to Figures 6, 7, 8, and 9. Predetermined holes 150 are connected to each other in the stacking direction Y and the flow direction Z to form the flow paths 800 (see parts 810, 811, 812, 813, 814, and 815). Then, in the fin portion 8, a plurality of spiral flow paths 800 are formed, extending in the flow direction Z of the coolant, as shown in Figure 9.

[0022] 7, the spiral center axis 13 of the spiral flow path 800 is formed in only one row in the stacking direction Y of the plates 81-89 of the fin portion 8, and is formed in multiple rows in the perpendicular direction X perpendicular to the stacking direction Y of the plates 81-89 and the flow direction Z of the coolant. Note that in the drawings of the present embodiment 1 and the following embodiments (except for FIG. 9), the spiral center axis 13 is indicated by a black circle.

[0023] The spiral flow paths 800 adjacent to each other in the perpendicular direction X are formed in an intertwined manner. Specifically, as shown in Fig. 8 and Fig. 9, the spiral flow paths 800 are intertwined and partially connected in the middle, as shown by the spiral R1 indicated by the solid arrow and the spiral R2 indicated by the dashed arrow of the spiral flow path 800. Note that the spirals R1 and R2 shown in Fig. 9 are only examples, and other portions are formed in the same relationship.

[0024] In order to verify how the coolant behaves when it is circulated through this flow path 800, a numerical calculation was performed using a three-dimensional fluid simulation, and the results are shown in Fig. 10. As shown in Fig. 10, it can be seen that the coolant flow lines 16 are formed in a spiral shape in multiple rows along the perpendicular direction X of the plates 81-89. As shown in Figs. 8A to 8E, the heat generated by the heating element 2 is conducted to the plates 81-89 that constitute the base portion 1 and the fin portion 8, and is dissipated from the wall surface of the flow path 800 to the coolant.

[0025] In the heat sink 100, the cooling liquid does not have temperature unevenness, and the temperature can be kept constant from the vicinity of the heat generating element 2 to the distant region in the stacking direction Y, thereby improving the heat dissipation performance of the heat sink 100. For this reason, it is important to know how to prevent temperature unevenness from occurring in the cooling liquid. According to the heat sink 100 of the first embodiment, the spiral center axis 13 of the spiral flow path 800 formed by connecting predetermined holes 150 of the plates 81 to 89 in the stacking direction Y and the flow direction Z is formed in only one row in the stacking direction Y, so that the flow of the cooling liquid in the fin portion 8 is reliably diffused in a single stroke from the vicinity of the heat generating element 2 to the distant region.

[0026] Therefore, the coolant is uniformly stirred from the vicinity of the heat generating element 2 to the distant area, eliminating temperature unevenness in the coolant and improving heat dissipation performance. With this configuration, it is possible to easily ensure the cross-sectional area of ​​the heat conduction path and the heat dissipation area within the fin portion 8.

[0027] Furthermore, since the spiral central axes 13 are formed in a plurality of rows in the orthogonal direction X of the fin portion 8, and adjacent spiral flow paths 800 are formed in an intertwined manner on a plane, by slightly shifting the positions of the holes 150 of adjacent plates in the stacking direction Y, a step-like step portion 19 is formed in the flow path 800 as shown in Fig. 8C, and the heat dissipation area can be increased. Moreover, since the plates 81 to 89 adjacent in the stacking direction Y are connected without any gaps, the cross-sectional area of ​​the heat conduction path can be increased, and the heat dissipation performance can be improved.

[0028] In addition, the base portion 1 on which the heating element 2 is mounted is parallel to the flow direction Z of the cooling liquid, and the length W (see FIG. 2) of one side of the mounting surface on which the heating element 2 is mounted is generally sufficiently long compared to the thickness T (see FIG. 13) of each of the plates 81-89. For this reason, if the stacking direction of the plates were set to the direction of the length W, the number of plates required would increase, but in this application, the stacking direction Y of the plates 80 is set to a direction perpendicular to the flow direction Z of the cooling liquid and the perpendicular direction X, so that the number of plates 80 required can be reduced and the contact or bonding surfaces between the plates 81-89 can be reduced, which makes it possible to improve manufacturability and reduce thermal resistance, i.e., improve heat dissipation performance.

[0029] The plates 80 are made of a material with good thermal conductivity, such as aluminum or copper. When the plates 80 are stacked, pressure is applied to press the plates 80 adjacent to each other in the stacking direction Y together, reducing the thermal resistance between the contact surfaces and improving the heat dissipation performance. At this time, the plates 80 may be tightly attached to each other by caulking or the like so that they do not separate. Alternatively, the plates 80 may be metallically joined together by brazing, diffusion bonding, or friction stir welding to form a joint, which can reduce the contact thermal resistance to zero and further improve the heat dissipation performance.

[0030] 5 are just an example. As long as the flow passage 800 formed by the holes 150 of the plates 80 being connected to each other in the stacking direction Y and the flow direction Z is spiral, the spiral central axis 13 is formed in only one row in the stacking direction Y of the plates 80, the spiral central axis 13 is formed in multiple rows in the perpendicular direction X of the fin portion 8, and the spiral flow passages 800 adjacent to each other in the perpendicular direction X are intertwined and partially connected, the shape of the holes 150 and the number of the plates 80 are not important.

[0031] In addition, it is not necessarily necessary to use the fastening plate 3 to fasten the base portion 1 and the water jacket 7 and ensure watertightness. The base portion 1 and the water jacket 7 may be fastened directly with bolts 4, a liquid gasket may be used instead of the O-ring 17, or the base portion 1 and the water jacket 7 may be directly joined by brazing or friction stir welding.

[0032] Furthermore, without using the base portion 1 and the water jacket 7, plates without holes may be brazed to the top and bottom surfaces of the plates 81 to 89 in the stacking direction Y, respectively, to ensure watertightness and form the flow paths 800. Although the flow paths 800 shown in Figures 7, 8 and 9 have a portion where adjacent flow paths 800 are intertwined with each other, they do not necessarily need to be intertwined and may always be separated from each other.

[0033] Next, a method for manufacturing the heat sink of the first embodiment configured as described above will be described. Each of the plates 81-89 is formed by opening a large number of different holes 151-159 in each of the plates 81-89 (first step). Next, the plates 81-89 are stacked in the stacking direction Y to form a spiral flow path 800 in which predetermined holes 150 of each of the plates 81-89 are connected to each other in the stacking direction Y and the flow direction Z (second step).

[0034] Then, after the second step, in a third step, pressure is applied from the stacking direction Y to pressurize and adhere the plates 81-89 adjacent in the stacking direction Y to each other. Alternatively, the plates 81-89 adjacent in the stacking direction Y are brazed to each other at their contact points. Alternatively, the plates 81-89 adjacent in the stacking direction Y are diffusion bonded to each other at their contact points. Alternatively, the plates 81-89 adjacent in the stacking direction Y are friction stir bonded to each other at their contact points. Then, the fin portion 8 is formed. The heat sink 100 is formed using the fin portion 8.

[0035] According to the heat sink of the first embodiment configured as described above, In a heat sink having a fin portion in which a plurality of plates are stacked in a stacking direction, A flow direction of the cooling liquid introduced into the heat sink is perpendicular to the stacking direction, Each of the plates has a plurality of holes formed therein, When the plates are stacked in the stacking direction, the holes of the plates are connected to each other in the stacking direction and the flow direction to form a flow path that is formed in a spiral shape toward the flow direction, The spiral central axis of the flow path is formed in only one row in the stacking direction. Moreover, according to the method for manufacturing the heat sink of the first embodiment configured as described above, In the above-mentioned method for manufacturing a heat sink, a first step of forming a plurality of said holes in each of said plates; and a second step of stacking the plates in the stacking direction, and connecting the holes of the plates in the stacking direction and the flow direction to form a spiral flow path in the flow direction. The spiral coolant flow path formed by connecting the holes in the plates has a single line of spiral central axes in the stacking direction, and the flow of the coolant is reliably diffused in a single stroke from near the heat generating element to far areas in the stacking direction. As a result, the coolant is stirred uniformly from near the heat generating element to far areas, eliminating temperature unevenness and improving heat dissipation performance.

[0036] Furthermore, according to the heat sink of the first embodiment, The fin portion has a plurality of types of plates having different hole patterns, A spiral flow path can be easily formed.

[0037] Furthermore, according to the heat sink of the first embodiment, The flow paths are formed in a plurality of rows in a direction perpendicular to the stacking direction and the flow direction. Since the spiral central axes are formed in a plurality of rows in the perpendicular direction, the heat dissipation area can be easily increased.

[0038] Furthermore, according to the heat sink of the first embodiment, The flow paths are formed by connecting the flow paths adjacent to each other in the perpendicular direction at a part thereof. Since the flow paths adjacent to each other in the perpendicular direction are partially intertwined and connected, the heat dissipation area can be further increased.

[0039] Furthermore, according to the heat sink of the first embodiment, The plates adjacent to each other in the stacking direction are formed by pressure contact from the stacking direction, Furthermore, according to the method for manufacturing the heat sink of the first embodiment, After the second step, a third step is provided in which pressure is applied from the stacking direction to press and adhere the plates adjacent to each other in the stacking direction, Since adjacent plates in the stacking direction are connected without any gaps, the cross-sectional area of ​​the heat conduction path can be increased, thereby improving heat dissipation performance.

[0040] Furthermore, according to the heat sink of the first embodiment, Since a joint is formed at a portion where the plates adjacent to each other in the stacking direction contact each other, The plates can be securely connected in the stacking direction.

[0041] Furthermore, according to the heat sink of the first embodiment, The joint is formed by brazing, Furthermore, according to the method for manufacturing the heat sink of the first embodiment, After the second step, a third step is provided in which the portions where the plates adjacent to each other in the stacking direction are in contact with each other are brazed and joined. The contact thermal resistance can be reduced to zero, and the effect of improving heat dissipation performance can also be obtained.

[0042] Furthermore, according to the heat sink of the first embodiment, The joint is formed by diffusion bonding, Furthermore, according to the method for manufacturing the heat sink of the first embodiment, After the second step, a third step is provided in which the portions where the plates adjacent to each other in the stacking direction are in contact with each other are diffusion-bonded. The contact thermal resistance can be reduced to zero, and the effect of improving heat dissipation performance can also be obtained.

[0043] Furthermore, according to the heat sink of the first embodiment, Since the welded portion is formed by friction stir welding, Furthermore, according to the method for manufacturing the heat sink of the first embodiment, After the second step, a third step is provided in which the portions where the plates adjacent to each other in the stacking direction are in contact with each other are friction stir welded. The contact thermal resistance can be reduced to zero, and the effect of improving heat dissipation performance can also be obtained.

[0044] In the following embodiment, the differences from the above-mentioned embodiment 1 will be mainly described, and therefore the description of the same parts as those in the above-mentioned embodiment 1 will be omitted as appropriate.

[0045] Embodiment 2 Fig. 11A is a plan view showing a configuration of a base portion of a heat sink and a heat generating element mounted thereon according to embodiment 2. Fig. 11B is an enlarged left side view of the base portion and fin portion of the heat sink shown in Fig. 11A, and the heat generating element mounted thereon.

[0046] The heat sink of the second embodiment differs from the heat sink of the first embodiment in that a plurality of heat generating bodies 2 to be cooled by the heat sink are mounted on the heat sink. At least one spiral central axis 13 of the flow passage 800 of the fin section 8 is present in each region of the fin section 8 to which heat is input from each heat generating body 2. FIG. 11B shows an example in which each heat generating body 2 has seven spiral central axes 13. Thus, the heat sink 100 has 14 spiral central axes 13 in its entirety, that is, the spiral flow passage 800 is formed in 14 locations.

[0047] There is no need to provide flow paths 800 in areas where there are no heat generating bodies 2 to be cooled. By providing spiral center axis 13 of flow paths 800 intensively in the area of ​​fin section 8 where heat is input from heat generating body 2, the flow rate of the cooling liquid flowing into each flow path 800 can be improved, and as a result, the flow rate of the cooling liquid can be improved, compared to the case where flow paths 800 are also provided in areas of fin section 8 where heat is not input from heat generating body 2. The faster the flow rate of the cooling liquid, the higher the heat transfer coefficient, and therefore the heat dissipation performance can be improved.

[0048] According to the heat sink of the second embodiment configured as described above, The same effects as those of the first embodiment are obtained, and A plurality of heat generating elements can be mounted on the heat sink, and the flow paths are formed only in the areas where heat is input from each of the heat generating elements. The amount of coolant flowing into each flow path can be increased, and as a result, the flow velocity of the coolant can be increased. The faster the flow velocity of the coolant, the greater the heat transfer coefficient, and therefore the heat dissipation performance can be improved.

[0049] Embodiment 3 Fig. 12A is a plan view showing a configuration of a plate of a heat sink according to embodiment 3. Fig. 12B is an enlarged plan view showing a configuration of a dashed line portion J of the plate shown in Fig. 12A. Fig. 13 is a side view of the plate of the heat sink according to embodiment 3.

[0050] According to the heat sink 100 of the third embodiment, the shortest distance L between adjacent holes 150 in the plate 80 is formed to be equal to or greater than the thickness T (FIG. 13) of the plate 80. For example, when the holes 150 in the plate 80 are formed by punching, by forming the shortest distance L between adjacent holes 150 to be equal to or greater than the thickness T of the plate 80, it is possible to prevent tearing or sagging in the portion where the shortest distance L between the adjacent holes 150 is located.

[0051] According to the heat sink configured as in the third embodiment, The same effects as those of the above embodiment are obtained, and The plate is formed so that the shortest distance between adjacent holes is equal to or greater than the thickness of the plate. This can prevent the plate from tearing or dripping.

[0052] Embodiment 4 In the heat sink according to embodiment 4, the total number of plates 80 to be stacked is N (N is an integer of 7 or greater if the number is odd, and an integer of 6 or greater if the number is even). When N is an odd number, the number of types of patterns of holes 150 in plates 80 is ((N-1) / 2)+1. When N is an even number, the number of types of holes 150 in plates 80 is N / 2.

[0053] 7, 8 and 9, the shape of the spiral flow channel 800 is symmetrical with respect to the spiral central axis 13 and the stacking direction Y of the plates 80. For this reason, a spiral shape can be formed by appropriately selecting the thickness T of the plates 80 and stacking the plates 80 so that the shapes of the holes 150 of the plates 80 in each stacking direction Y are symmetrical with respect to the spiral central axis 13. Therefore, when N is an odd number, it is sufficient to prepare ((N-1) / 2)+1 types of patterns for the holes 150 of the plates 80. When N is an even number, it is sufficient to prepare N / 2 types of patterns for the holes 150 of the plates 80.

[0054] This makes it possible to reduce the number of different patterns of the holes 150 on the plates 80, as compared to a case in which all N plates 80 are formed so that the types of patterns of the holes 150 are different, thereby improving productivity.

[0055] According to the heat sink configured as in the fourth embodiment, The same effects as those of the above embodiment are obtained, and If the total number of plates is N (N is an integer of 7 or more if the number is odd, and an integer of 6 or more if the number is even), When the N is an odd number, the number of types of patterns is ((N-1) / 2)+1. When the N is an even number, the number of types of patterns is N / 2, so The number of different types of plate hole patterns can be reduced, improving manufacturability.

[0056] Embodiment 5. Fig. 14A is a plan view showing the configuration of a fin member 888 for manufacturing the fin portion 8 of the heat sink according to embodiment 5. Fig. 14B is a plan view showing the configuration of the fin portion 8 cut out from the fin member 888 shown in Fig. 14A. In the case of embodiment 5, for example, plate members are formed (first step) that are plates 81-89 having a pattern of holes 151-159 as shown in Fig. 5 and have a planar area at least twice the area of ​​the fin portion 8.

[0057] Next, the plate members are stacked in the stacking direction Y (second step) and subjected to a bonding step or joining step to manufacture a fin member 888 (FIG. 14A, third step). Next, fin portions 8 are cut out to the required size (dotted line portion in FIG. 14B) according to the desired size of the flow path 800 to manufacture them (FIG. 14B, fourth step).

[0058] In manufacturing the fin section 8 having the flow paths 800, the process of pressurizing, brazing, diffusion bonding, or friction stir bonding the plates 80 together in the stacking direction Y requires the most man-hours and generates costs. Therefore, in the fifth embodiment, a fin member 888 larger than the size of the fin section 8 having the necessary flow paths 800 is manufactured in advance as described above.

[0059] Then, a plurality of fin portions 8 of a preset size are cut out. By manufacturing in this manner, when forming a plurality of fin portions 8 each having the necessary flow paths 800, the process of pressure bonding, brazing, diffusion bonding, or friction stir bonding, which requires the most man-hours, can be performed in one step, and the number of processes can be significantly reduced.

[0060] According to the heat sink configured as in the above-mentioned embodiment 5, The same effects as those of the above embodiment are obtained, and After forming a fin member by carrying out the first to third steps using a plate member having an area twice or more the area of ​​the fin portion, The method further includes a fourth step of cutting out a plurality of the fin portions from the fin member. When manufacturing multiple heat sinks, the number of steps can be significantly reduced.

[0061] Although the present application describes various exemplary embodiments and examples, the various features, aspects, and functions described in one or more embodiments are not limited to application to a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless variations not illustrated are assumed within the scope of the technology disclosed in this application, including, for example, modifying, adding, or omitting at least one component, and further, extracting at least one component and combining it with a component of another embodiment. [Explanation of symbols]

[0062] 1 base portion, 100 heat sink, 13 spiral central axis, 150 hole, 151 hole, 152 hole, 153 hole, 154 hole, 155 hole, 156 hole, 157 hole, 158 hole, 159 hole, 16 flow line, 17 O-ring, 19 step portion, 2 heating element, 3 fastening plate, 4 bolt, 5 supply path, 6 discharge path, 7 water jacket, 8 fin portion, 80 plate, 800 flow path, 81 plate, 82 plate, 83 plate, 84 plate, 85 plate, 86 plate, 87 plate, 88 plate, 89 plate, 810 portion, 811 portion, 812 portion, 813 portion, 814 portion, 888 fin member, 9 flow path inlet, L shortest distance, T thickness, Y stacking direction, X Orthogonal direction, Z flow direction.

Claims

1. In a heat sink having a fin portion in which a plurality of plates are stacked in a stacking direction, A flow direction of the cooling liquid introduced into the heat sink is perpendicular to the stacking direction, Each of the plates has a plurality of holes formed therein, When the plates are stacked in the stacking direction, the holes of the plates are connected to each other in the stacking direction and the flow direction to form a flow path that is formed in a spiral shape toward the flow direction, A heat sink in which the spiral central axes of the flow paths are formed in only one row in the stacking direction.

2. The heat sink according to claim 1 , wherein the fin portion includes a plurality of types of the plates each having a different hole pattern.

3. If the total number of plates is N (N is an integer of 7 or more if the number is odd, and an integer of 6 or more if the number is even), When the N is an odd number, the number of types of patterns is ((N-1) / 2)+1. The heat sink according to claim 2 , wherein when the N is an even number, the number of types of the patterns is N / 2.

4. The heat sink according to claim 1 , wherein the flow paths are formed in a plurality of rows in a direction perpendicular to the stacking direction and the flow direction.

5. The heat sink according to claim 4 , wherein the flow paths are formed by partially connecting the flow paths adjacent to each other in the perpendicular direction.

6. 6. The heat sink according to claim 1, wherein a plurality of heat generating elements can be mounted on the heat sink, and the flow passages are formed only in the regions receiving heat from the respective heat generating elements.

7. The heat sink according to claim 1 , wherein the plates adjacent to each other in the stacking direction are formed by being pressed tightly against each other in the stacking direction.

8. The heat sink according to claim 1 , wherein a joint is formed at a location where the plates adjacent in the stacking direction contact each other.

9. The heat sink according to claim 8 , wherein the joint is formed by brazing.

10. The heat sink according to claim 8 , wherein the joint is formed by diffusion bonding.

11. The heat sink according to claim 8 , wherein the joint is formed by friction stir welding.

12. The heat sink according to claim 1 , wherein the plate is formed so that the shortest distance between adjacent holes is equal to or greater than the thickness of the plate.

13. A method for manufacturing a heat sink according to any one of claims 1 to 12, comprising the steps of: a first step of forming a plurality of said holes in each of said plates; and a second step of stacking the plates in the stacking direction and connecting the holes in the plates in the stacking direction and the flow direction to form a spiral flow path toward the flow direction.

14. The method for manufacturing a heat sink according to claim 13 , further comprising, after the second step, a third step of applying pressure from the stacking direction to pressurize and adhere the plates adjacent in the stacking direction to each other.

15. The method for manufacturing a heat sink according to claim 13 , further comprising, after the second step, a third step of brazing and joining the plates adjacent to each other in the stacking direction at locations where the plates contact each other.

16. The method for manufacturing a heat sink according to claim 13 , further comprising, after the second step, a third step of diffusion bonding the plates at locations where the plates adjacent in the stacking direction contact each other.

17. The method for manufacturing a heat sink according to claim 13 , further comprising, after the second step, a third step of friction stir welding the plates at locations where the plates adjacent in the stacking direction contact each other.

18. A plate member having an area twice or more the area of ​​the fin portion is used to form a fin member by carrying out the first to third steps, The method for manufacturing a heat sink according to claim 14 , further comprising a fourth step of cutting out a plurality of the fin portions from the fin member.

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