JP2014053442A - Plate laminated type cooling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce pressure loss and to suppress corrosion in a plate laminated type cooling device.SOLUTION: A plate laminated type cooling device includes: a metallic bottom plate; a plurality of fin laminates which are fixed to the bottom plate while being separated from each other and each of which is formed by laminating a plurality of fins; and a housing in which the bottom plate and the plurality of fin laminates are housed and a flow inlet and a flow outlet for a coolant are formed. Each of the plurality of fins has a cut-off mark on one side surface on a short side. The plurality of fins are formed by processing both side surfaces on the longitudinal side into a corrugated shape.

Description

  The present invention relates to a cooling device suitably used for a semiconductor, and more particularly to a plate laminated cooling device having a fin laminated body therein.

  In recent years, with an increase in capacity and size of CPUs (Central Processing Units), inverters, and the like, heat transfer characteristics of cooling devices (heat sinks) used for them have been improved. As one of the cooling devices having high heat transfer characteristics, a plate stack type cooling device capable of taking a large heat transfer area with respect to the volume is known.

  The plate lamination type cooling apparatus according to Patent Document 1 is configured by a heat radiating plate in which slit-like long holes are processed. A plurality of long holes are formed in the heat radiating plate by punching, and a plurality of fin portions are formed in the heat radiating plate by the plurality of long holes. At the base of the fin portion, a bridge portion for connecting the fin portions is provided so that the plurality of fin portions do not fall apart.

  The heat dissipating plates are alternately stacked in several layers by brazing. Such a plate stack type cooling device has a high cooling capacity because the flow path can be reduced and the fin surface area can be increased. On the other hand, since the refrigerant flow rapidly expands and contracts in the bridge portion, pressure loss increases, and corrosion products and contamination accumulate on the bridge portion, thereby promoting corrosion of the heat dissipation plate.

JP 2012-013249 A

  The present invention has been made to solve such problems, and aims to reduce pressure loss and suppress corrosion in a plate stack type cooling apparatus.

  A plate lamination type cooling apparatus according to the present application includes a metal bottom plate, a plurality of fin laminates, each of which is fixed to the bottom plate with a space therebetween, and a plurality of fins laminated on each other, The housing is provided with a housing that accommodates the individual fin laminates and has an inlet and an outlet for the refrigerant. Each of the plurality of fins has a cut mark on one side surface of the short side.

  Since the refrigerant flows smoothly through the flow path, an increase in pressure loss and corrosion due to the bridge portion can be suppressed.

It is a disassembled perspective view which shows the whole plate laminated | stacked cooling device in connection with this invention. 1 is a perspective view showing an assembly of a plate stack type cooling apparatus according to Embodiment 1. FIG. It is a top view which shows the form of a fin. It is a top view showing the flow of the refrigerant in the inside of a plate lamination type cooling device. It is sectional drawing which shows the plate lamination type cooling device with which the heat generating body was mounted | worn. It is a perspective view which shows the heat radiating plate in connection with Embodiment 1 of this invention. It is a perspective view which shows the baseplate in connection with Embodiment 1 of this invention. It is a perspective view showing the state which mounted the laminated body of the heat sink plate by Embodiment 1 on the baseplate. It is sectional drawing which shows the state by which the fin by Embodiment 1 was laminated | stacked. FIG. 6 is a perspective view showing an assembly of a plate stack type cooling device according to a second embodiment. It is a perspective view showing the state by which the laminated body of the heat sink plate by Embodiment 2 is welded and fixed to the bottom plate. FIG. 6 is a perspective view showing an assembly of a plate stack type cooling device according to a third embodiment. FIG. 10 is a front view showing a heat dissipation plate according to the third embodiment. FIG. 10 is a perspective view showing a bottom plate according to the third embodiment. It is a perspective view showing the state which mounted the laminated body of the heat sink plate by Embodiment 3 on the baseplate.

  DESCRIPTION OF EMBODIMENTS Embodiments of a plate stack type cooling device (heat sink) according to the present invention will be described below in detail with reference to the drawings. In addition, this invention is not limited to the following description, In the range which does not deviate from the summary of this invention, it can change suitably.

Embodiment 1 FIG.
FIG. 1 is an exploded perspective view showing an entire plate stack type cooling apparatus according to the present invention. The plate stack type cooling apparatus 100 includes an assembly 12 and a casing (case) 30. The housing 30 includes a housing 3, a top plate 4, a pipe 5a, and a pipe 5b. The pipe 5 a and the pipe 5 b are provided in the housing 3. The top plate 4 is joined to the housing 3 in order to confine the refrigerant 20 inside the housing 30. The refrigerant 20 flows into the housing 30 from the pipe 5a (inlet) and flows out from the pipe 5b (outlet). The assembly 12 includes a bottom plate 2 and a plurality of fin laminates 6. The bottom plate 2 and the fin laminate 6 are fixed to each other and housed in the housing 30. The bottom plate 2 of the assembly 12 is joined to the housing 3. The fin laminate 6 of the assembly 12 is joined to the top plate 4.

  FIG. 2 is a perspective view showing the overall structure of the assembly of the plate stack type cooling apparatus. A plurality of fin laminates 6 are joined to the bottom plate 2. Each fin laminate 6 is formed by laminating a plurality of long fins 8. In the figure, the fin laminate 6 is composed of six fins 8, but the number of laminates is increased or decreased depending on the required thermal performance. The fin laminates 6 are arranged at intervals and constitute a plurality of flow paths 7. In addition to the role of forming the refrigerant flow path, the fin laminate 6 conducts heat from a heating element (such as a power semiconductor) in the stacking direction. The corrugated irregularities provided on the side surfaces of the fins 8 increase the heat transfer area and improve the cooling performance. Since the refrigerant flows while colliding with the convex portion, the effect of improving the cooling performance by the collision jet can be obtained. If the cooling performance is sufficient, the side surface of the fin 8 may be smooth.

  FIG. 3 shows a plan view of the fin. The long fin 8 has a long side surface 8a and a short side surface 8b. Each fin 8 is formed with a hole 11 and a cut mark 31. When stacking the heat radiating plates, the holes 11 are engaged with each other and fixed (see FIG. 6). The fin 8 is made of a material that can be brazed or soldered, such as copper, aluminum, and iron, and has good thermal conductivity. However, considering the thermal conductivity and ease of brazing, aluminum is suitable. As a processing method of the hole 11, there is embossing. Corrugated irregularities are formed on both longitudinal side surfaces 8a. The cutting mark 31 is formed on the side farther from the hole 11 out of the two short side surfaces 8b.

  FIG. 4 shows the flow of the refrigerant in the plate stack type cooling apparatus of the first embodiment. The refrigerant 20 flows in from the pipe 5a, passes through a plurality of flow paths 7 provided in the assembly 12, and then flows out from the pipe 5b. If the bridge part which connects a fin to the assembly 12 remains, expansion and contraction of the refrigerant occur in the bridge part, and pressure loss occurs there. Further, corrosion products stay in the bridge portion. If the corrosion product stays, corrosion accelerates in the staying portion, and cooling performance and reliability deteriorate. On the other hand, in this Embodiment, since there is no bridge part, the refrigerant | coolant 20 flows smoothly. Further, the corrosion product does not stay.

  A CPU, LSI, electronic device (inverter, etc.), power semiconductor, and the like are mounted as an object to be cooled on the plate stack type cooling apparatus configured as described above. The heating element is disposed on the top plate 4 or the housing 3. FIG. 5 shows a cross-sectional view of a plate stack type cooling apparatus equipped with a heating element. In this figure, the heating element 54 is in contact with the top plate 4. The arrow represents the direction in which the refrigerant 20 flows. For power semiconductors, Si or SiC that generates less heat than Si is used. Applicable refrigerants include water, antifreeze, various coolants such as LLC (Long Life Coolant) and lubricating oil, and gases such as air and hydrogen. A power module equipped with a power module that operates at a high temperature is sealed with an epoxy resin in order to control cracks in a metal bonding material (solder) that occurs in a power cycle test. In the heat cycle test, cracks and peeling may occur in the epoxy resin, but according to the plate lamination type cooling apparatus related to the present application, the occurrence of cracks and peeling is reduced.

  The plate lamination type cooling apparatus shown in the first embodiment is manufactured by the following method. FIG. 6 shows a perspective view of the heat dissipation plate according to the first embodiment of the present invention. The heat radiating plate 1 includes a plurality of fins 8 and a bridge portion 9. Each fin 8 is formed with a protrusion 10 and a hole 11. The bridge portion 9 serves to connect the fins 8 so that the fins 8 do not fall apart. The heat radiating plate 1 is made of a material that can be brazed or soldered, such as copper, aluminum, and iron, and has good thermal conductivity, but aluminum is suitable in consideration of thermal conductivity and ease of brazing. As a processing method of the heat radiating plate 1, there are press processing, laser cutting processing, etching processing, and the like. The uneven shape provided on the side surface on the longitudinal side of the fin 8 enlarges the heat transfer area and improves the cooling performance.

  FIG. 7 shows a perspective view of the bottom plate. The bottom plate 2 is made of a material that can be brazed or soldered, such as copper, aluminum, or iron, and has good thermal conductivity, like the heat radiating plate 1, and has a flat plate shape approximately the same size as the heat radiating plate 1. Yes. Since the protruding portion 10 of the heat radiating plate 1 is inserted into the bottom plate 2, the same number of through holes 13 as the protruding portion 10 are drilled. The arrangement pitch of the through holes 13 is the same as that of the protrusions 10 of the heat radiating plate 1.

  FIG. 8 is a perspective view illustrating a state in which the laminated body of the heat radiating plates is mounted on the bottom plate. The heat dissipation plate 1 and the bottom plate 2 are fixed by laminating the first layer of the heat dissipation plate 1 on the bottom plate 2 and press-fitting the protrusions 10 of the heat dissipation plate 1 into the through holes 13 of the bottom plate 2. Next, the second heat dissipation plate 1 is laminated on the first heat dissipation plate 1, and the protrusion 10 of the second heat dissipation plate 1 is inserted into the hole 11 of the first heat dissipation plate 1. The first layer heat radiation plate 1 and the second layer heat radiation plate 1 are fixed. Similarly, the third layer heat dissipation plate is fixed on the second layer heat dissipation plate, the fourth layer heat dissipation plate is fixed on the third layer heat dissipation plate, and so on. . Thereafter, the bridge portion 9 is removed by shearing or laser processing. After the removal, an assembly 12 composed of a plurality of fin laminates 6 and the bottom plate 2 is formed (see FIG. 2). In the present invention, since the bridge portion does not exist in the assembly, the refrigerant does not expand or contract at the bridge portion. It is possible to prevent pressure loss generated in the bridge portion and retention of corrosion products in the bridge portion.

  FIG. 9 is a cross-sectional view showing the relationship between the fin laminate and the bottom plate. Since the bridge portion is removed, a cut mark 31 is formed on one side of the short side surface of each fin 8 (see FIG. 3). Even if the bridge portion 9 is removed, the fins 8 and the bottom plate 2 are press-fitted and fixed so that they do not fall apart. The assembly 12 is accommodated in the housing 3. The housing 3 and the assembly 12, the assembly 12 and the top plate 4, and the top plate 4 and the housing 3 may be joined by brazing. After the housing 3 and the assembly 12 are joined by brazing, the top plate 4 and the sealing material are interposed. And may be assembled with screws or the like. The housing 3 is manufactured by sheet metal, die casting, or forging. When the housing 3 is manufactured by die casting, the material is limited and only aluminum is used. When the housing 3 is manufactured by sheet metal or forging, it is made of a material that can be brazed or soldered, such as copper, aluminum, or iron, and has good thermal conductivity, like the heat radiating plate.

  When the housing 3 is manufactured by die casting or forging, the pipe 5 and the housing 3 can be manufactured integrally, but may be manufactured separately. When the housing 3 is manufactured from sheet metal, it is impossible to manufacture the pipe 5 and the housing 3 as a single unit, and thus it is necessary to manufacture the pipe 5 and the housing 3 separately. When the pipe 5 is manufactured separately, the pipe 5 is manufactured by extrusion using a material that can be brazed or soldered, such as copper, aluminum, or iron, and has good thermal conductivity, like the heat radiating plate. The pipe 5 is united by joining the housing 3 by brazing or the like.

Embodiment 2. FIG.
FIG. 10 is a perspective view of the assembly of the plate stack type cooling apparatus according to the second embodiment of the present invention. The fin laminate 6 and the bottom plate 2 have welds (beads) 14. The welded portion 14 is continuously formed on the short side surface of the fin laminate 6. FIG. 11 is a perspective view showing a state in which a laminated body of heat radiation plates according to Embodiment 2 of the present invention is mounted on a bottom plate and then fixed by welding. In the first embodiment, the fins 8 and the bottom plate 2 are fixed by embossing, whereas in the second embodiment, the fins 8 and the bottom plate 2 are joined by welding. The rest is the same as in the first embodiment. There are laser welding, seam welding, arc welding, spot welding, etc., any of which can be used.

Embodiment 3 FIG.
FIG. 12 is a perspective view showing an assembly of the plate stack type cooling apparatus according to the third embodiment of the present invention. The fin 8 is provided with only two or more pin holes 18, and the other shapes are the same as those of the fin of the first embodiment. FIG. 13 is a front view illustrating a heat dissipation plate according to Embodiment 3 of the present invention. The fins 8 provided with two pin holes 18 are connected by a bridge portion 9.

  FIG. 14 is a perspective view showing a bottom plate according to Embodiment 3 of the present invention. On the bottom plate 2, projections (pins) 17 having a diameter slightly smaller than the size of the pin holes 18 of the heat radiating plate 1 are provided at the same pitch as the pin holes 18 of the heat radiating plate. Other parts are the same as those in the first embodiment.

  The plate lamination type cooling apparatus shown in the third embodiment is manufactured by the following method. FIG. 15 is a perspective view showing a state after the laminated body of the heat radiating plates according to the third embodiment of the present invention is mounted on the bottom plate. The plurality of heat dissipation plates 1 are inserted into the bottom plate 2 so that the protrusions 17 of the bottom plate 2 and the pin holes 18 of the heat dissipation plate 1 are aligned. Thereafter, the bridge portion 9 is removed as in the first embodiment. The subsequent manufacturing method is exactly the same as in the first embodiment. The protrusion 17 of the bottom plate 2 of the present embodiment is manufactured by die casting, forging, or the like.

  When SiC is used for the power semiconductor, the semiconductor device is operated at a higher temperature than that of Si in order to take advantage of its characteristics. In the plate lamination type cooling device on which the SiC device is mounted, higher reliability is required. Therefore, the merit of the present invention to realize a highly reliable plate lamination type cooling device becomes more effective.

  It should be noted that the present invention can be freely combined with each other within the scope of the invention, and each embodiment can be appropriately modified or omitted.

  DESCRIPTION OF SYMBOLS 1 Heat radiation plate, 2 Bottom plate, 3 Housing, 4 Top plate, 5 Pipe, 6 Fin laminated body, 7 Flow path, 8 Fin, 9 Bridge part, 10 Protrusion part, 11 hole part, 12 Assembly, 13 Through hole, 14 Welding Part, 17 protrusion, 18 pin hole, 20 refrigerant, 30 housing, 54 heating element, 100 plate laminated cooling device

Claims (5)

A metal bottom plate,
A plurality of fin laminates, each of which is fixed to the bottom plate at an interval, and each of which is a laminate of a plurality of fins;
A housing in which the bottom plate and the plurality of fin laminates are accommodated and a refrigerant inlet and outlet are formed;
Each of the plurality of fins has a cut mark on one side surface of the short side.   2. The plate stacked type cooling device according to claim 1, wherein the plurality of fins are processed in a corrugated shape on both side surfaces on a longitudinal side. 3.   The plate stack type cooling apparatus according to claim 1 or 2, wherein the plurality of fins are connected to each other by embossing processed on a main surface.   The plate stack type cooling device according to claim 1, wherein the plurality of fins are connected to each other by weld beads.   The plate stack type cooling device according to claim 1 or 2, wherein the plurality of fins are connected to each other by a pin penetrating a hole provided in a main surface.

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