Cooler for power devices

Abstract

To provide a cooling unit for a power device which is capable of reducing the number of constituent members and improving the processing and assembling efficiencies of the constituent members, and has high heat exchange performance.SOLUTION: A cooling unit for a power device includes a plate-shaped first case 10 made of an aluminum member, a thick frame-shaped second case 20, and a heat-receiving plate integrated fin 30 having a heat-receiving surface 31a joined to a heating element. A cooling liquid inlet 11 and a cooling liquid outlet 12 are provided at opposing sites of the first case. The second case has a thickness that suppresses distortion caused by heat when the heating element is joined, and a cooling liquid inflow guide portion 21 communicating with the cooling liquid inlet and a cooling liquid outflow guide portion 22 communicating with the cooling liquid outlet are formed at opposing sites. The heat-receiving plate integrated fin includes a plurality of ridges 34 forming cooling liquid flow passages 33 between adjacent portions thereof which are integrally formed in a region corresponding to a cooling-liquid circulation space 23 on the inner surface of the heat-receiving plate, and the first case, the second case and the heat-receiving plate and the ridges of the heat-receiving plate integrated fin are joined.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a cooler for a power device, and more particularly to a cooler for a power device, such as a power semiconductor, which is joined to a heat generating body in which the power device is incorporated. Su This invention relates to a cooler for cooling power devices. [Background technology]

[0002] In recent years, power semiconductors (power devices) that generate a large amount of heat have been used to improve the switching performance of motors in hybrid vehicles, plug-in hybrid vehicles, electric vehicles, high-speed trains, etc. Therefore, to ensure stable operation of power semiconductors (power devices) that generate a large amount of heat, a cooling device with high heat exchange performance and reliability is required.

[0003] Conventionally, air-cooled fan-type heat sinks have been used to cool heat-generating elements, but as the amount of heat generated increases, the cooling performance of the air-cooled fan method becomes limited, so water-cooled coolers and liquid-cooled jackets are now being used (see, for example, Patent Documents 1, 2, 3, and 4).

[0004] Patent document 1 states: , release It is composed of an upper component that constitutes a top wall having a heat body mounting surface, and a lower component that constitutes a bottom wall and a peripheral wall. a casing having a The inward protrusion, the inlet guide portion for guiding the coolant, the outlet guide portion for guiding the coolant, and the pin fins scattered throughout the coolant flow path are brazed to the top surface of the outward flange that constitutes the bottom wall and peripheral wall of the lower component. The cooler is made of It is disclosed in the patent document. In the structure described in 1, An insulating laminate is brazed to the top wall, which has a heating element mounting surface, and a warp suppression plate made of a material with a linear expansion coefficient lower than that of aluminum is brazed to the outer surface of the bottom wall, thereby preventing warping of the casing, insulating laminate, and warp suppression plate due to heat generated when the heating element is mounted by soldering.

[0005] Patent Documents 2 and 3 teeth, A structure in which a housing composed of a base plate, a frame member (peripheral wall portion), and a lid body, and a fin body composed of first fins and second fins having zigzag flow paths arranged inside the housing are integrated by brazing. The liquid cooling jacket Furthermore, Patent Documents 2, 3, and 4 disclose a technique in which the fin body has zigzag fins in which first fins and second fins are arranged alternately in the front-rear direction, i.e., in the flow direction of the coolant, and the zigzag fins are formed by cutting with a multi-cutter. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-98439 [Patent Document 2] Patent No. 6698111 [Patent Document 3] Patent No. 6508398 [Patent Document 4] Patent No. 6314802 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the structure described in Patent Document 1 has an inward protrusion, an inlet guide portion, an outlet guide portion, and pin fins scattered throughout the coolant flow path that are integral with the upper component that makes up the cooler, which are brazed to the upper surface of an outward flange that makes up the bottom wall and peripheral wall of the lower component, and a warp suppression plate is brazed to the outer surface of the lower component, which raises concerns that the processing of the components will be complicated and that assembly will be time-consuming.

[0008] The devices described in Patent Documents 2, 3, and 4 have a structure in which a housing consisting of a base plate, a frame member (peripheral wall portion), and a lid body is brazed to a fin body consisting of a first fin and a second fin with zigzag flow paths arranged inside the housing. As a result, there is a concern that the processing of the components will be complicated and assembly will be time-consuming.

[0009] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a power device cooler that reduces the number of components, improves the efficiency of processing and assembling the components, and has high heat exchange performance. [Means for solving the problem]

[0010] In order to achieve the above object, the power device cooler of the present invention comprises a plate-like first case member, a second case member having a thick, annular, closed frame shape and having one open end to which the first case member is attached in close contact, sealing the one open end, and a heat reception plate-integrated fin member as a third case member, which has a heat reception plate that is in close contact with the other open end of the second case member and has a plurality of fins that are housed inside the second case member integrated with the inner surface of the heat reception plate that is in close contact with the other open end of the second case member and seals the other open end, and at least one of a coolant inlet and a coolant outlet that communicate with a coolant flow path between the fins is provided in either the first case member or the heat reception plate, and a coolant inlet guide portion and a coolant outlet guide portion that circulate the coolant between the coolant flow path and the coolant inlet and the coolant outlet are provided in the second case member. the first case member is brazed to the one open end of the second case member, the heat receiving plate is brazed to the other open end of the second case member, and further, the tip portions of the fins are brazed to the first case member, the plurality of fins are formed by flat protrusions standing on the inner surface of the heat receiving plate, and the first case member, the second case member and the heat receiving plate-integrated fin member are formed of a 6000 series (Al-Mg-Si series) aluminum alloy and are brazed and joined using a flux containing cesium fluoride (CsF). It is characterized by do.

[0012] In this invention, as long as the first case, the second case, and the heat receiving plate-integrated fins are formed of aluminum (including aluminum alloy) members, the second case may be either a member obtained by slicing an aluminum extrusion or an aluminum forging, and the heat receiving plate-integrated fins may be either a member obtained by cutting an aluminum extrusion or an aluminum forging.

[0014] With this configuration, the first case, the second case, and the heat-receiving-plate-integrated fins are joined into an integral structure by brazing, thereby providing airtightness and durability.

[0016] By configuring in this manner, the flux has the effect of removing the oxide film on the aluminum and promoting the flow of the brazing material, thereby improving the brazing properties. [Effects of the Invention]

[0017] According to the present invention, as configured above, the following effects can be obtained.

[0018] The present invention Therefore, a power device cooler can be constructed using a plate-shaped first case member, a thick-walled frame-shaped second case member with high rigidity that is less likely to cause thermal distortion when the heat generating element is mounted by bonding, and a heat receiving plate-integrated fin member that suppresses resistance during heat transfer, thereby reducing the number of components, improving the efficiency of processing and assembling the components, and achieving high heat exchange performance.

[0019] In addition, the present invention Therefore, the first case member, the second case member, and the heat receiving plate-integrated fin member can be joined into an integrated structure by brazing, making them airtight and durable, so that in addition to (1) above, even higher heat exchange performance can be obtained and the lifespan can be increased.

[0020] Furthermore, the present invention According to this, brazing properties can be improved. , more In addition, the assembly efficiency of the components can be improved, high heat exchange performance can be obtained, and the life span can be increased. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a plan view showing, in partial cross section, a state in which a cooler according to a first embodiment of the present invention is in use. [Figure 2] FIG. 2 is a cross-sectional view taken along line II in FIG. [Figure 3] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Figure 4] 3A is a cross-sectional view taken along line III-III in FIG. 1, and FIG. 3B is an enlarged view of part IV in FIG. [Figure 5] FIG. 2 is an exploded perspective view showing a first case, a second case, and a heat receiving plate-integrated fin in the first embodiment. [Figure 6] FIG. 10 is a plan view showing, in partial cross section, a state in which a cooler according to a second embodiment of the present invention is in use. [Figure 7] FIG. 7 is a cross-sectional view taken along line VV in FIG. 6. [Figure 8] FIG. 7 is a cross-sectional view taken along line VI-VI in FIG. [Figure 9] FIG. 10 is an exploded perspective view showing a first case, a second case, and a heat receiving plate-integrated fin in a second embodiment. [Figure 10] FIG. 2 is a perspective view showing an example of a shape before being formed into a heat receiving plate-integrated fin according to the present invention. [Figure 11] FIG. 10 is a perspective view showing an example of another shape member before being formed into a heat receiving plate-integrated fin in the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0022] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0023] First Embodiment As shown in FIGS. 1 to 5, the cooler 1 according to the present invention comprises a plate The case member is shaped like a The first case 10 and a thick frame having the same shape as the outline of the first case 10 The case member is shaped like a The heat receiving surface 31a is connected to the power module 2, which incorporates a power device such as a power semiconductor as a heat generating element. The case material is The heat plate integrated fin 30 is laminated and joined. It is composed of:The first case 10, the second case 20, and the heat-receiving-plate-integrated fins 30 are made of aluminum members, which includes aluminum alloys.

[0024] The first case 10 is formed by pressing an aluminum plate member having a generally rectangular shape with arc-shaped corners. A coolant inlet 11 is provided at one of two opposing locations in the center of the first case 10 in the short direction, and a coolant outlet 12 is provided at the other opposing location. Positioning through holes 13 are provided near the four corners. The through holes 13 do not need to be provided near the four corners, and may be provided at any location, for example, near two diagonally opposite corners.

[0025] The thick-walled frame-shaped second case 20 has a thickness that suppresses distortion due to heat when joining the power module 2, and a coolant inflow guide portion 21 that communicates with the coolant inlet 11 is formed on one of the opposing parts in the short side direction of the second case 20, and a coolant outflow guide portion 22 that communicates with the coolant outlet 12 is formed on the other opposing part. These coolant inflow guide portion 21 and coolant outflow guide portion 22 communicate with a coolant circulation space 23 inside the second case 20, and are arranged in a planar shape so that the coolant can be widely distributed in the coolant circulation space 23. The visual shape is The coolant flow space 23 side expands. Open R Trapezoidal shape It is formed.

[0026] The second case 20 can be formed simply by slicing an aluminum extrusion to a predetermined thickness. The second case 20 may also be formed from an aluminum forged material. When the second case 20 is formed from a forged material, it can be produced, for example, by a mechanical press using a forging die.

[0027] The heat receiving plate integrated fin 30 has a plurality of ridges 33 that form coolant flow passages 33 between adjacent portions in the area excluding the joining area 32 that abuts against the second case 20 on the inner surface of the heat receiving plate 31, i.e., the area corresponding to the coolant flow space 23. 4, and these ridges 34 and the heat receiving plate 31It is formed integrally.

[0028] 10, an aluminum extrusion having a plate portion 35 forming the heat receiving plate 31 and a raised fin portion 36, leaving only the joining regions 32 on both sides of the plate portion 35, is cut to the size of the cooler to produce a pre-formed fin portion 39. A multi-cutter (not shown) with multiple disk cutters arranged side by side is used to form multiple ridges 34 that form coolant flow channels 33 between adjacent portions of this pre-formed fin portion 39, and the joining regions 32 are formed by cutting the ridges 34 on the sides of the plate portion 35 that are perpendicular to the joining regions 32 on both sides to form the joining regions 32, thereby forming (producing) the heat receiving plate-integrated fin 30. Alternatively, the ridges 34 may be formed using the multi-cutter after the joining regions 32 have been formed by cutting the sides of the pre-formed fin 39 that are perpendicular to the joining regions 32 on both sides of the plate portion 35.

[0029] As another method for forming the heat receiving plate-integrated fin 30, as shown in Figure 11, an aluminum extrusion profile having multiple ridges 34 that form coolant flow passages 33 between adjacent portions in the area remaining the joint areas 32 on both sides of the plate portion 35 that forms the heat receiving plate 31 is cut to the size of the cooler to produce a pre-formed profile 39A, and then the ridges 34 on the sides perpendicular to the joint areas 32 on both sides of the plate portion 35 are cut to form the joint areas 32, thereby forming (forming) the heat receiving plate-integrated fin 30.

[0030] The heat receiving plate-integrated fin 30 may be formed from forged aluminum material. When the heat receiving plate-integrated fin 30 is formed from forged material, it can be manufactured using, for example, a mechanical press using a forging die.

[0031] The plate-shaped first case 10, the thick-walled frame-shaped second case 20, and the heat receiving plate-integrated fin 30 formed as described above are made of any one of brazable aluminum alloys, such as 1000 series (pure aluminum), 3000 series (Al-Mn), 6000 series (Al-Mg-Si), and 8000 series (Al-Fe).

[0032] Here, the first case 10, the second case 20, and the heat receiving plate-integrated fin 30 are formed of a 6000 series (Al-Mg-Si) aluminum alloy, such as A6063 alloy, specifically, an aluminum alloy containing, by mass, 0.6% Si, 0.35% Fe, 0.1% Cu, 0.1% Mn, 0.9% Mg, 0.1% Cr, 0.1% Zn, and 0.01% Ti, with the remainder being Al and unavoidable impurities. Note that the material of the first case 10 does not necessarily have to be 6063 alloy; it may also be a brazing sheet with the same alloy as the core material.

[0033] In the case of 6000 series (Al-Mg-Si) aluminum alloys, brazing is performed using a flux containing cesium fluoride (CsF). The flux is applied to the joining surfaces of the first case 10, second case 20, and heat-receiving-plate-integrated fin 30 when brazing them. Compared to conventional Nocolok flux, the flux containing cesium fluoride (CsF) begins to react at a lower temperature, which has the effect of reducing the impact of magnesium precipitation on brazeability when joining alloys containing magnesium.

[0034] When brazing the first case 10, the second case 20, and the heat receiving plate-integrated fins 30, a brazing filler metal layer is formed on the brazing filler metal, or the brazing filler metal is applied to at least one of the members to be joined among the first case 10, the second case 20, and the heat receiving plate-integrated fins 30, or a brazing filler metal in the form of a thin plate, powder, or rod is used. Specifically, a brazing filler metal layer is formed on the brazing filler metal, or the brazing filler metal is applied to at least one of the members to be joined among the first case 10, the second case 20, and the heat receiving plate-integrated fins 30, or a brazing filler metal in the form of a thin plate, powder, or rod is used, and the first case 10, the second case 20, and the heat receiving plate-integrated fins 30 are assembled and heated in a furnace at a predetermined temperature for brazing.

[0035] When joining a power module 2 to the cooler 1 configured as described above, after removing flux residue from the heat receiving surface 31a of the heat receiving plate-integrated fin 30, the heat receiving surface 31a is plated with Ni, and the heat receiving surface 31a of the cooler 1 and the power module 2 are joined by soldering. The flux residue can be removed, for example, using a wet blasting device in which an abrasive and liquid (water) accelerated by compressed air collide with the cooler 1 to process the surface. The plating process is performed using Ni plating.

[0036] In the cooler 1 configured as described above, the coolant supplied to the coolant inlet 11 flows through the coolant inlet guide 21 into the coolant flow space 23, flows through the coolant flow passages 33 between the plurality of ridges 34 integrally formed on the inner surface of the heat receiving plate 31, and is discharged from the coolant outlet 12 through the coolant outlet guide 22. As a result, the heat generated from the power devices of the power module 2 joined to the heat receiving surface 31a is The coolant removes heat, making the power device more efficient. It can be cooled efficiently.

[0037] In the above explanation, the coolant inlet 11 and the coolant outlet 12 are provided in the first case 10, but the coolant inlet 11 and the coolant outlet 12 may also be provided in the heat receiving plate 31 of the heat receiving plate-integrated fin 30.

[0038] Second Embodiment As shown in Figures 6 to 9, the cooler 1A of the second embodiment has a coolant inlet section 40 and a coolant outlet section 50 that extend outward at opposing positions in the short direction of the central part of a substantially rectangular base.

[0039] The cooler 1A of the second embodiment has a rectangular base 14 and rectangular projections 14a and 14b that protrude outward at opposing positions in the short side direction in the center of the base 14. Overhanging portions 15a, 15b A plate having The case member is shaped like a 1 case 10A and a thick frame plate with the same shape as the outline of the first case 10A The case member is shaped like aThe second case 20A has an outline identical to that of the first case 10A and has a heat receiving surface 31a to be joined to a power module 2 incorporating a power device such as a power semiconductor as a heat generating body. The case material is The heat plate integrated fin 30A is laminated and bonded. It is composed of:

[0040] First case 10A is formed by pressing an aluminum plate member having a substantially rectangular base 14 with arc-shaped corners, and rectangular protrusions 15a and 15b that protrude outward at opposing locations in the short side direction at the center of base 14. Coolant inlet 11 is provided in one of protrusions 15a at the opposing locations in the short side direction at the center of first case 10A, and coolant outlet 12 is provided in the other protrusion 15b at the opposing location. Note that protrusions 15a and 15b may have a shape other than rectangular, such as a semicircular arc or semi-elliptical shape.

[0041] The thick-walled frame-shaped second case 20A has a thickness sufficient to suppress distortion due to heat during bonding of the power module 2. Rectangular protruding frame portions 24a and 24b protrude outward at opposing locations along the short side of the second case 20A. A coolant inflow guide portion 21A communicating with the coolant inlet 11 is formed in one of the protruding frame portions 24a, and a coolant outflow guide portion 22A communicating with the coolant outlet 12 is formed in the other protruding frame portion 24b. The coolant inflow guide portion 21A and the coolant outflow guide portion 22A communicate with the coolant flow space 23 inside the second case 20A. The second case 20A can be formed by the same forming method as the second case 20 of the first embodiment. That is, the second case 20A can be formed by simply slicing an aluminum extrusion to a predetermined thickness, or by forging an aluminum material.

[0042] The heat receiving plate-integrated fin 30A is a heat receiving plate 31A having a rectangular heat receiving plate body 37 and rectangular protruding portions 38a, 38b that protrude outward at opposing positions in the short side direction at the center of the heat receiving plate body 37. The heat receiving plate 31A has a plurality of protruding strips 38a, 38b that form coolant flow passages 33 between adjacent portions in the region excluding the joining region 32 that abuts against the second case 20A on the inner surface of the heat receiving plate 31A, i.e., the region corresponding to the coolant flow space 23. 4, and these ridges 34 and the heat receiving plate 31A The heat reception plate-integrated fin 30A can be formed by the same forming method as the heat reception plate-integrated fin 30 of the first embodiment. That is, the heat reception plate-integrated fin 30A can be formed by cutting an aluminum extrusion or by forging an aluminum material.

[0043] In the second embodiment, the overhanging portions 15a and 15b of the first case 10A, the overhanging frame portions 24a and 24b of the second case 20A, and the overhanging portions 38a and 38b of the heat reception plate-integrated fins 30A form a coolant inlet 40 and a coolant outlet 50. In the above description, the coolant inlet 11 is provided in the overhanging portion 15a of the first case 10A, and the coolant outlet 12 is provided in the overhanging portion 15b, but the coolant inlet 11 and the coolant outlet 12 may be provided in the overhanging portions 38a and 38b of the heat reception plate 31A of the heat reception plate-integrated fins 30A.

[0044] In the second embodiment, other parts are the same as those in the first embodiment, so the same parts are given the same reference numerals and the description thereof will be omitted.

[0045] In the cooler 1A configured as described above, the coolant supplied to the coolant inlet 11 flows into the coolant flow space 23 via the coolant inlet portion 40, flows through the coolant flow passages 33 between the plurality of ridges 34 integrally formed on the inner surface of the heat receiving plate 31A, and is discharged from the coolant outlet 12 via the coolant outlet portion 50. As a result, the heat generated from the power devices of the power module 2 joined to the heat receiving surface 31a is The coolant removes heat, making the power device more efficient. It can be cooled efficiently.

[0046] According to the cooler 1, 1A of the embodiment configured as described above, the three components, namely, the plate-shaped first case 10, 10A, the thick-walled frame-shaped second case 20, 20A having high rigidity that is less likely to cause thermal distortion when the power module 2 is mounted by joining, and the heat receiving plate-integrated fins 30, 30A that suppress resistance during heat transfer, are brazed together, thereby reducing the number of components and improving the processing and assembly efficiency of the components. Furthermore, since the components are joined into an integrated structure by brazing, airtightness and durability can be achieved, and high heat exchange performance and an extended lifespan can be achieved.

[0047] In the above embodiment, the first case 10, the second case 20, and the heat receiving plate-integrated fin 30 are described as being formed from a 6000 series (Al-Mg-Si) aluminum alloy, for example, an A6063 alloy. However, the same effects as described above can be obtained when the first case 10, the second case 20, and the heat receiving plate-integrated fin 30 are formed from a brazable aluminum alloy other than the 6000 series (Al-Mg-Si) aluminum alloy, such as a 1000 series (pure aluminum), 3000 series (Al-Mn), or 8000 series (Al-Fe) aluminum alloy. [Explanation of symbols]

[0048] 1,1A cooler 10,10A Case 1 11 Coolant inlet 12 Coolant outlet 20,20A Second case 21,21A Coolant inflow guide part 22,22A Coolant outflow guide 23 Coolant circulation space 30,30A Heat receiving plate integrated fin 31,31A heat receiving plate 31a Heat receiving surface 32 Joint area 33 Coolant flow path 34 Convex strip

Claims

[Claim 1] a plate-shaped first case member; a second case member having a thick, annular, closed frame shape, one open end of which is tightly attached to the first case member, thereby sealing the one open end; a heat receiving plate-integrated fin member as a third case member, the third case member having a heat receiving plate that is in close contact with the other open end of the second case member and seals the other open end, and a plurality of fins that fit inside the second case member are integrated with the inner surface of the heat receiving plate; At least one of a coolant inlet and a coolant outlet communicating with a coolant flow passage between the fins is provided in either the first case member or the heat receiving plate, the second case member is provided with a coolant inlet guide portion and a coolant outlet guide portion that allow the coolant to flow between the coolant flow passage and the coolant inlet and the coolant outlet, The first case member is brazed to the one open end side of the second case member, the heat receiving plate is brazed to the other open end of the second case member; and The tip of the fin is brazed to the first case member, The plurality of fins are formed by flat protrusions standing on the inner surface of the heat receiving plate, The first case member, the second case member, and the heat-receiving-plate-integrated fin member are formed of a 6000 series (Al-Mg-Si series) aluminum alloy, and are brazed and joined using a flux containing cesium fluoride (CsF). A cooler for power devices characterized by:

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