Heat sink

Abstract

[Problem] To provide a heat sink able, with a lightweight and compact configuration, to effectively cool an object to be cooled which generates a large amount of heat, e.g., a CPU or a chipset. [Solution] A heat sink comprising a metal heat dissipation promoting part 3 fixed to a metal heat receiving substrate 2 to which heat from an object to be cooled is transmitted, and a fluid supplying part 4 which supplies a fluid for cooling to the heat dissipation promoting part 3, wherein: the heat dissipation promoting part 3 is formed by arranging, in a second direction Y, a plurality of heat dissipating parts 31, each of which has an inverted V-shape or inverted U-shape cross-section, extends in a first direction X, and has the base thereof fixed to a heat dissipating surface 22 of the heat receiving substrate 2; in a plate surface of each heat dissipating part 31, a plurality of through-holes 35 which connect an inside space 30 and an outside space 36 of the heat dissipating part 31 are formed; and in the fluid supplying part 4, at least one end part of each heat dissipating part 31 in the first direction X and the plurality of through-holes 35 serve as out / inlets, allowing a fluid F to flow through the inside spaces 30 which are chevron-shaped and formed between the heat dissipating parts 31 and the heat receiving substrate 2, whereby heat from the heat receiving substrate 2 and the heat dissipation promoting part 3 is dissipated to the outside by means of the fluid F.

Description

heat sink

[0001] The present invention relates to a heat sink suitable for use as a cooling device for cooling an object to be cooled, such as an electronic circuit device that generates a large amount of heat, such as a CPU (Central Processing Unit) or a chipset of a computer.

[0002] Conventionally, a proposed cooling device of this type is a CPU cooler that includes a metal heat sink consisting of a base portion that acts as a heat absorber that contacts the CPU and a number of plate-shaped fins protruding from its upper surface (the side opposite the CPU), and a fan that is provided on the tip side of the plate-shaped fins of the heat sink to force air to flow between the plate-shaped fins (see, for example, Patent Document 1).

[0003] In a cooling system that forcibly flows air between the plate-shaped fins and dissipates heat from the surface of the plate-shaped fins into the air, it is necessary to increase the surface area of ​​the plate-shaped fins to ensure heat dissipation efficiency. In other words, with the recent trend toward more sophisticated CPUs and increased heat generation, conventional cooling systems require larger plate-shaped fins or more plate-shaped fins. This inevitably leads to larger and heavier cooling systems, and ultimately to larger and heavier circuit boards and computers that incorporate the cooling systems.

[0004] Also known is a heat dissipation structure for dissipating heat generated from a semiconductor, which comprises a heat dissipation plate made of a material that dissipates heat easily, one end of the upper surface of which is flat, and the other end of which has a heat dissipation section of a certain height to increase the heat dissipation area, and a fan attached to one end of the upper surface of the heat dissipation plate and arranged parallel to the heat dissipation section with its axis perpendicular to the upper surface, and which has multiple slits in the wall surface of the heat dissipation plate to increase the heat dissipation effect of the heat dissipation plate (see, for example, Patent Document 2).

[0005] When multiple slits are provided on the wall surface of the heat sink, the cooling performance can be improved by allowing the cooling fluid to flow through the slits. However, in the above-mentioned heat dissipation structure, most of the cooling fluid blown toward the heat sink from the fan attached to one end of the top surface of the heat sink flows along the wall surface of the heat dissipation fins, and only a small amount of the cooling fluid passes through the slits, so the cooling performance of the heat sink (heat dissipation structure) cannot be significantly improved.

[0006] Japanese Patent Application Publication No. 2003-152153 Japanese Utility Model Registration No. 3019105

[0007] In view of the above-mentioned situation, the present invention aims to solve the problem of providing a heat sink that can effectively cool objects that generate a lot of heat, such as CPUs and chipsets, with a lightweight and compact configuration.

[0008] In light of this current situation, the inventors conducted extensive research and discovered that in order to efficiently dissipate heat from the plate surface of the heat dissipation section, multiple through holes are formed in the plate surface of the metal heat dissipation plate that makes up the heat dissipation section, and that by configuring the through holes so that a cooling fluid actively passes through them, it is possible to effectively cool the object to be cooled with an extremely lightweight and compact configuration, and this led to the completion of the heat sink of the present invention.

[0009] That is, the present invention includes the following inventions.

[0010] (1) A heat sink comprising: a metal heat-receiving base to which heat from an object to be cooled is transferred; a metal heat-dissipation promoting part fixed to the heat-receiving base and promoting the dissipation of the heat; and a fluid supply part for supplying a cooling fluid to the heat-dissipation promoting part, wherein the heat-dissipation promoting part has left and right base ends fixed to the heat-dissipating surface of the heat-receiving base, and comprises a plurality of heat-dissipating parts, each of which has an inverted V- or U-shaped cross section and extends along a first direction of the heat-dissipating surface, arranged in a second direction perpendicular to the first direction; a plurality of through holes formed in the plate surface of each heat-dissipating part to connect the internal space of the heat-dissipating part with the outside; and the fluid supply part circulates the fluid through at least one end of each heat-dissipating part in the first direction and the plurality of through holes as inlets / outlets, in the mountain-shaped internal space formed between each heat-dissipating part and the heat-receiving base, and the heat from the heat-receiving base and the heat-dissipation promoting part is dissipated to the outside by the fluid.

[0011] (2) The heat sink described in (1), wherein each of the heat dissipation portions is composed of a pair of left and right heat dissipation plates extending along a first direction of the heat dissipation surface, and the tip ends of the two heat dissipation plates abut or are close to each other so as to be configured in an inverted V-shape or an inverted U-shape in cross section.

[0012] (3) A heat sink described in (1) or (2), in which a first regulating wall that regulates the flow of the fluid by blocking the space between the heat dissipation sections arranged adjacent to each other in the second direction is provided at the end of the heat dissipation promotion section in the first direction.

[0013] (4) The heat sink according to any one of (1) to (3), further comprising a second restriction wall that closes the end of the heat dissipation promotion portion in the second direction and restricts the flow of the fluid.

[0014] (5) A heat sink as described in (2), in which a pair of heat sinks are formed by cutting a lotus-type porous metal molding having a plurality of pores extending in one direction formed by a metal solidification method in a direction intersecting the direction in which the pores extend, and the base ends of the pair of heat sinks are fixed on the heat sink surface at a fixed interval.

[0015] (6) A heat sink as described in (1), in which the heat dissipation section is formed by bending a flat metal heat dissipation plate obtained by cutting a lotus-type porous metal molding having a plurality of pores extending in one direction formed by a metal solidification method in a direction intersecting the direction in which the pores extend.

[0016] (7) The heat sink according to (6), wherein the plurality of heat dissipation portions arranged in the second direction are continuously formed by bending the flat metal heat dissipation plate.

[0017] The heat sink of the present invention configured as described above has a plurality of heat dissipation sections that are inverted V- or U-shaped in cross section and extend along a first direction of the heat dissipation promotion section, arranged in a second direction of the heat dissipation promotion section, and is configured so that almost all of the cooling fluid that flows through the mountain-shaped internal space formed between the heat dissipation section and the heat receiving base passes through a plurality of through holes formed in the plate surface of the heat dissipation section.This ensures a sufficient contact area between the fluid and the heat dissipation section, allowing for efficient heat exchange.Therefore, the object to be cooled can be effectively cooled with a lightweight and compact configuration without making the surface area of ​​the heat dissipation section larger than necessary or providing a large number of heat dissipation sections.

[0018] Furthermore, by forming each heat dissipation section using a pair of left and right heat dissipation plates extending along the first direction of the heat dissipation surface and making the tips of both heat dissipation plates abut or come close to each other, it is possible to easily and properly form a heat dissipation section that can ensure sufficient contact area between the cooling fluid and the heat dissipation section.

[0019] In addition, in a case where a first restriction wall is provided at the first-direction end of the heat dissipation acceleration section to restrict the flow of the fluid by blocking the gap between adjacent heat dissipation sections arranged in the second direction, for example, a cooling fluid drawn into the first-direction end of the heat dissipation section by a fluid supply section is guided through the first-direction end as an inlet to flow through the internal space of the heat dissipation section, and then substantially all of the fluid is discharged to the outside through the through-holes of the heat dissipation section as an outlet. On the other hand, a cooling fluid discharged from the fluid supply section toward the heat dissipation section is prevented from being directly discharged to the outside from the first-direction end of the heat dissipation acceleration section by the first restriction wall. Therefore, a sufficient contact area between the cooling fluid and the heat dissipation section is ensured, resulting in efficient heat exchange.

[0020] In addition, in a cooling device having a second restriction wall that blocks the second-direction end of the heat dissipation acceleration section to restrict the flow of the fluid, for example, the cooling fluid drawn in by the fluid supply section is guided to flow into the internal space of the heat dissipation section from the first-direction end, and approximately all of the fluid passes through the through-holes of the heat dissipation section as an outlet and is then discharged to the outside. On the other hand, the cooling fluid discharged from the fluid supply section is restricted by the second restriction wall from being directly discharged to the outside from the second-direction end of the heat dissipation acceleration section, so that the cooling fluid is guided to flow into the internal space of the heat dissipation section from the through-holes of the heat dissipation section as an inlet, and approximately all of the fluid is then discharged to the outside from the first-direction end as an outlet. Therefore, a sufficient amount of cooling fluid can be ensured to pass through the through-holes of the heat dissipation section, thereby achieving excellent heat dissipation performance.

[0021] In addition, in a case where a lotus-type porous metal molding having a plurality of pores extending in one direction, formed by a metal solidification method, is cut in a direction intersecting the direction in which the pores extend, and the base ends of the pair of heat dissipation plates formed are fixed to the heat dissipation surface at a certain interval, a heat dissipation section in which a large number of through holes are formed on the plate surface to connect the internal space of the heat dissipation section with a valley-shaped external space located outside it can be easily constructed at low cost.

[0022] In addition, in a case where the heat dissipation section is formed by bending a flat metal heat dissipation plate obtained by cutting a lotus-type porous metal compact having a plurality of pores extending in one direction formed by a metal solidification method in a direction intersecting the direction in which the pores extend, there is an advantage that heat dissipation sections of various shapes can be easily formed. Moreover, by providing a through-hole at the upper end of the heat dissipation section that connects the internal space of the heat dissipation section with the external space, it is possible to increase the contact area between the cooling fluid and the heat dissipation section.

[0023] Furthermore, when a flat metal heat sink is bent to form the plurality of heat sink sections arranged in the second direction in a continuous manner, the plurality of heat sink sections can be formed simultaneously and can be firmly fixed to the heat sink surface of the heat receiving base.

[0024] FIG. 1 is an exploded perspective view showing the configuration of a heat sink according to an embodiment of the present invention; FIG. 2 is a perspective view showing the heat sink in an assembled state; FIG. 3 is a cross-sectional view showing the heat sink in an assembled state; (a) is a plan view showing a main portion of a plate-shaped material constituting the heat sink, and (b) is a cross-sectional view of the plate-shaped material; FIG. 4 is a cross-sectional view showing another embodiment of the heat sink; (b) is a cross-sectional view showing a modified example of the heat sink; (c) is a cross-sectional view showing another modified example of the heat sink; (d) is a cross-sectional view showing yet another modified example of the heat sink; (e) is a cross-sectional view showing yet another modified example of the heat sink; (f) is a cross-sectional view showing yet another modified example of the heat sink; (f) is a perspective view showing yet another modified example of the heat sink.

[0025] 1 to 3 show an embodiment of a heat sink 1 according to the present invention. The heat sink 1 has a contact surface 21 that contacts an object to be cooled (not shown), such as a CPU, and is equipped with a heat-receiving base 2 made of a metal such as aluminum, iron, or copper to which heat from the object to be cooled is transferred through the contact surface 21, a heat-dissipation promoting section 3 that is disposed on a heat-dissipating surface 22 of the heat-receiving base 2 on the opposite side of the contact surface 21, and a fluid supply section 4 that supplies a cooling fluid F to the heat-dissipation promoting section 3. Various types of cooling fluid F can be used, such as air or water, but the present embodiment will describe an example in which air is used.

[0026] The heat dissipation promotion section 3 is fixed to the heat dissipation surface 22 of the heat receiving base 2. The heat dissipation promotion section 3 is configured by arranging a plurality of heat dissipation sections 31, each having an inverted V-shaped or inverted U-shaped cross section, extending in a first direction X of the heat dissipation surface 22 in a second direction Y perpendicular to the first direction X. Each heat dissipation section 31 has a pair of left and right heat dissipation plates 32 made of aluminum, iron, copper, or the like, and base ends 33 of the heat dissipation plates 32 are fixed to the heat dissipation surface 22 at a fixed interval in the first direction X by brazing, adhesive, or the like (see FIG. 3 ). The tip ends 34 of the two heat dissipation plates 32 are arranged so as to abut or be close to each other, thereby forming the heat dissipation section 31, each having an inverted V-shaped or inverted U-shaped cross section and having a triangular internal space 30 tapering upward, extending along the first direction X of the heat dissipation surface 22.

[0027] The pair of left and right heat dissipation plates 32 constituting the heat dissipation section 31 are formed from plate-shaped materials obtained by cutting a lotus-type porous metal compact having a plurality of pores extending in one direction, which has been formed by, for example, a metal solidification method, in a direction intersecting the direction in which the pores extend. Such lotus-type porous metal compacts can be formed by known methods such as the pressurized gas method (for example, the method disclosed in Japanese Patent Registration No. 4235813) or the thermal decomposition method.

[0028] 4 shows a plate-shaped material 32a of a predetermined thickness cut out from the lotus-type porous metal molding. This plate-shaped material 32a has through-holes made of the pores, i.e., a large number of through-holes 35 that open on the plate surface of the plate-shaped material 32a and extend in the thickness direction of the plate-shaped material 32a. Furthermore, as shown in FIG. 4(a), a skin region 37 without through-holes (pores) 35 is provided at the peripheral edge of the plate-shaped material 32a cut out from the lotus-type porous metal molding.

[0029] 2 and 3 are constructed using plate-shaped materials 32a cut out from the lotus-type porous metal molding, thereby making it possible to easily and at low cost construct a pair of left and right heat dissipation plates 32, each having a large number of through-holes 35 formed on the plate surface that connect the mountain-shaped internal space 30 to the outside, i.e., the valley-shaped external space 36 located between adjacent heat dissipation sections 31. Furthermore, by bonding the skin region 37 formed around the heat dissipation plate 32 to the heat dissipation surface 22 of the heat receiving base 2, a sufficient bonding area between the heat receiving base 2 and the base end 33 of the heat dissipation plate 32 is ensured, resulting in sufficient bonding strength and efficient heat transfer from the heat receiving base 2 to the heat dissipation section 31.

[0030] As will be described later, the cooling fluid F is supplied to circulate through the internal space 30 of the heat dissipation section 31 in response to the suction force of the fluid supply section 4, etc., and heat exchange occurs when the cooling fluid F passes through the through holes 35 of the heat dissipation plate 32, thereby dissipating the heat transferred to the heat-receiving base 2 and the heat dissipation promotion section 3 to the outside (see, for example, FIG. 3 ). Note that the plate-shaped material 32a cut out from the lotus-type porous metal molding also has blind, bottomed holes in addition to the through holes 35, and these bottomed holes also have the effect of increasing the surface area of ​​the heat dissipation plate 32 and promoting heat dissipation from the heat dissipation plate 32.

[0031] The fluid supply unit 4 has a cooling fan 41 such as a conventionally known propeller fan, sirocco fan, or turbo fan, and a case 5 disposed to cover the outer periphery of the heat dissipation promotion unit 3. In this embodiment, in response to the suction force of the cooling fan 41 disposed above the heat dissipation promotion unit 3, the cooling fluid F flows into the internal space 30 from both ends of the heat dissipation unit 31 in the first direction X as inlets, as shown in Fig. 2, and then passes through the through holes 35 of the heat dissipation unit 31 as outlets as shown in Fig. 3, whereby heat exchange occurs, and the cooling fluid F is then discharged as exhaust air H above the heat dissipation promotion unit 3.

[0032] It is also possible to close one end of the heat dissipation portion 31 in the first direction X, and use only the other end as an inlet to allow the cooling fluid F to flow into the internal space 30. Furthermore, instead of the above-described embodiment in which the fluid supply portion 4 is formed by the case 5 and the cooling fan 41 arranged above it, a cooling fan may be installed at a position away from the heat receiving base 2 and the heat dissipation promotion portion 3, and a connecting pipe may be provided to connect the cooling fan and the heat dissipation promotion portion 3, and the cooling fluid F may be supplied to the heat dissipation promotion portion 3 via the connecting pipe.

[0033] As shown in FIG. 1 , the case 5 includes a top plate 51 to which the cooling fan 41 is attached, a pair of end plates 52 provided above the front and rear ends of the heat dissipation promotion portion 3 located at the end of the heat dissipation surface 22 in the first direction X, and a pair of side plates 53 provided on the left and right side surfaces of the heat dissipation promotion portion 3 located at the end of the heat dissipation surface 22 in the second direction Y, and these are formed from inexpensive synthetic resin moldings or the like. As shown in FIGS. 1 and 2 , below the end plates 52, a plurality of trapezoidal protrusions 54 are provided that close the valley-shaped external spaces 36 provided between the heat dissipation portions 31 arranged adjacent to each other in the second direction Y of the heat dissipation promotion portion 3, thereby forming first restriction walls that restrict the flow of fluid F at the end of the heat dissipation promotion portion 3 in the first direction X. Furthermore, as shown in FIG. 3 , the side plates 53 of the case 5 form second restriction walls that close the left and right side surfaces of the heat dissipation promotion portion 3 and restrict the flow of fluid F at the end of the heat dissipation promotion portion 3 in the second direction Y.

[0034] As described above, the heat sink 1 according to the present invention comprises a metal heat-receiving base 2 to which heat from an object to be cooled is transferred, a metal heat-dissipation promoting part 3 fixed to the heat-receiving base 2 to promote the dissipation of the heat, and a fluid supply part 4 for supplying a cooling fluid F to the heat-dissipation promoting part 3. The heat-dissipation promoting part 3 has left and right base ends 33 fixed to the heat-dissipating surface 22 of the heat-receiving base 2, and comprises a plurality of heat-dissipating parts 31, each having an inverted V- or U-shaped cross section and extending along a first direction X of the heat-dissipating surface 22, arranged continuously in a second direction Y perpendicular to the first direction X, and the fluid F passes through a plurality of through-holes 35 formed in the plate surface of each heat-dissipating part 31 to dissipate heat. Therefore, the heat sink 1, which has a lightweight and compact configuration, can be used to effectively cool an object to be cooled that generates a large amount of heat, such as a CPU or a chipset.

[0035] That is, the heat sink 1 according to this embodiment is configured such that, in response to the suction force of the fluid supply unit 4, a cooling fluid F flows into a mountain-shaped internal space 30 formed between each heat dissipation unit 31 and the heat receiving base 2 through at least one end of the heat dissipation unit 31 in the first direction X as an inlet, and the fluid F is discharged to an external space 36 through a plurality of through holes 35 formed in the plate surface of the heat dissipation unit 31 as an outlet. This ensures a sufficient contact area between the fluid F and the heat dissipation unit 31, and efficient heat exchange occurs when the fluid F flowing through the internal space 30 passes through the through holes 35 of the heat dissipation unit 31. Therefore, it is possible to dissipate heat transferred to the heat receiving base 2 and the heat dissipation promotion unit 3 to the outside without making the surface area of ​​the heat dissipation unit 31 larger than necessary or providing a large number of heat dissipation units 31, and it is possible to effectively cool an object to be cooled with a lightweight and compact configuration.

[0036] 3, the base ends 33 of a pair of left and right heat dissipation plates 32 constituting the heat dissipation portion 31 extending along the first direction X of the heat dissipation promotion portion 3 are fixed to the heat dissipation surface 22 of the heat receiving base 2, and the tip ends of both heat dissipation plates 32 are abutted or brought close to each other to form the heat dissipation portion 31 having an inverted V or U shape in cross section. With this configuration, it is possible to easily and appropriately form the heat dissipation portion 31 configured to effectively prevent, with a simple configuration, the fluid F that has flowed into the internal space 30 of the heat dissipation portion 31 in response to the suction force of the cooling fan 41 from flowing out from the upper part of the heat dissipation portion 31 to the external space 36, and to allow substantially all of the fluid F to pass through the numerous through holes 35 formed in the plate surface of the heat dissipation portion 31.

[0037] That is, by joining the base ends 33 of the heat sinks 32, which have been cut so as to be parallel to the heat sink surface 22 of the heat receiving base 2, by welding, brazing, using a conductive adhesive or the like while the base ends 33 are abutted against the heat sink surface 22, the base ends 33 of the heat sinks 32 can be easily and firmly fixed onto the heat sink surface 22 of the heat receiving base 2. Then, by butting the tip ends 34 of the pair of left and right heat sinks 32 against each other, a heat sink 31 of an appropriate shape having a mountain-shaped internal space 30 can be formed.

[0038] In the above embodiment, the first restriction wall, which is made of a trapezoidal protrusion 54 that restricts the flow of the cooling fluid F by blocking the gap between adjacent heat dissipation sections 31 arranged in the second direction Y, is provided at the end of the heat dissipation acceleration section 3 in the first direction X. Therefore, the fluid F that is attracted to the end of the heat dissipation acceleration section 3 in the first direction X due to the suction force of the cooling fan 41 is prevented from flowing into the valley-shaped external space 36 located between adjacent heat dissipation sections 31. Almost all of the fluid F is guided to flow into the internal space 30 of the heat dissipation section 31, and then can be discharged to the outside through the through-holes 35 of the heat dissipation section 31. Therefore, a sufficient contact area between the fluid F and the heat dissipation section 31 can be ensured, allowing efficient heat exchange. In addition, instead of the above-mentioned embodiment in which a plurality of trapezoidal protrusions 54 protruding below the end plate 52 of the case 5 constitute a first restricting section that blocks the space between heat dissipation sections 31 arranged adjacent to each other in the second direction Y, as shown in Figures 1 and 2, the first restricting wall may be constituted by attaching a trapezoidal plate or sheet material to the end of the heat dissipation section 31.

[0039] 3, when the left and right side surfaces of the heat dissipation promotion unit 3 are closed by second restriction walls formed by the side plates 53 of the case 5 to restrict the flow of the fluid F at the ends of the heat dissipation promotion unit 3 in the second direction Y, the suction force of the cooling fan 41 can be concentrated on at least one of the front and rear ends (ends in the first direction X) of the heat dissipation promotion unit 3. This effectively increases the amount of airflow of the fluid F flowing into the internal space 30 from the front and rear ends of the heat dissipation unit 31 and the amount of airflow of the fluid F passing through the through holes 35 of the heat dissipation unit 31, thereby enabling more efficient heat exchange.

[0040] 5, instead of the above-described embodiment configured to supply the cooling fluid F to the heat dissipation acceleration portion 3 in response to the suction force of the cooling fan 41, for example, a configuration may be adopted in which the fluid F is discharged downward from the cooling fan 41 disposed above the heat dissipation acceleration portion 3, and the fluid F is caused to flow into the internal space 30 of the heat dissipation portion 31 through the through-holes 35 of the heat dissipation plate 32 as an inlet to perform heat exchange, and then the fluid F is discharged to the outside of the heat dissipation portion 31 through either one of the ends of the heat dissipation portion 31 in the first direction X as an outlet. With this configuration, a sufficient contact area between the cooling fluid F discharged from the cooling fan 41 and the heat dissipation portion 31 can be ensured, thereby enabling efficient heat exchange.

[0041] Also, in the embodiment shown in Figure 5, it is desirable to provide a first regulating wall consisting of a trapezoidal protrusion 54 or the like that regulates the flow of fluid F by blocking the space between heat dissipation sections 31 arranged adjacent to each other in the second direction Y, and a second regulating wall consisting of a side plate 53 of the case 5 that blocks the left and right side portions of the heat dissipation promotion section 3 to regulate the flow of fluid F at the ends of the heat dissipation promotion section 3 in the second direction Y, thereby ensuring a sufficient air volume of fluid F passing through the through hole 35 of the heat dissipation section 31 and enabling efficient heat exchange.

[0042] As shown in Fig. 4, instead of the above-described embodiment in which the heat dissipation section 31 has an inverted V-shaped or inverted U-shaped cross section as shown in Fig. 3, the heat dissipation section 31 is formed using a plate-shaped material 32a formed by cutting a lotus-type porous metal body having a plurality of pores extending in one direction formed by a metal solidification method in a direction intersecting the pore extension direction. Alternatively, the heat dissipation section 31 may be formed with a plurality of through holes 35 by machining the plate surface with a drill. However, this configuration makes it difficult to form a large number of through holes 35 in the plate surface of the heat dissipation section 31, which inevitably increases the manufacturing cost of the heat dissipation section 31. Therefore, it is desirable to form the heat dissipation section 31 using a plate-shaped material 32a formed by a metal solidification method as shown in the above-described embodiment, thereby forming a large number of through holes 35 in the plate surface of the heat dissipation section 31 that communicate the mountain-shaped internal space 30 formed between the heat dissipation section 31 and the heat-receiving base 2 with the valley-shaped external space 36 located outside it.

[0043] 6 shows an embodiment in which a heat dissipation section 31 is formed by bending a metal heat dissipation plate made of a flat plate-shaped material 32a formed by cutting a lotus-type porous metal compact having a plurality of unidirectional pores formed by a metal solidification method in a direction intersecting the pore extension direction. This configuration allows the heat dissipation section 31 to be easily formed into various specific shapes, such as a trapezoidal heat dissipation section with a flat upper end, a heat dissipation section with an arc-shaped upper end, or an inverted V or U cross-sectional shape, instead of a triangular shape tapering upward. Furthermore, a through-hole 35 can be provided at the upper end of the heat dissipation section 31 to communicate the internal space 30 of the heat dissipation section 31 with the external space 36 located outside it, thereby advantageously increasing the contact area between the cooling fluid F and the heat dissipation section 31.

[0044] 7, a metal heat sink made of a flat plate-shaped material 32a may be formed by cutting a lotus-type porous metal body having a plurality of pores extending in one direction formed by a metal solidification method in a direction intersecting the direction in which the pores extend, and bending the resulting plate-shaped material to form a plurality of heat sink portions 31 arranged continuously in the second direction Y of the heat sink surface 22. This configuration has the advantage that a plurality of heat sink portions 31 can be formed simultaneously and can be firmly fixed to the heat sink surface 22 of the heat-receiving base 2.

[0045] Although the present invention has been described above in terms of an embodiment, it is not limited to this. For example, instead of the solid, flat, cubic metal heat-receiving base 2, the contact surface 21 and the heat-dissipating surface 22 may be curved in an arc, or the heat-receiving base 2 may be hollow instead of solid. Furthermore, the heat-receiving base 2 may be made of a wide range of materials used in conventional heat sinks, such as aluminum, iron, or copper. It may also be constructed with a heat pipe inside, or may be made of the heat pipe itself.

[0046] In addition, instead of the above-described embodiment in which the upper end of the heat dissipation section 31 is formed into a flat surface or a V-shaped surface as shown in Fig. 5, the upper end of the heat dissipation section 31 may be formed into an arc shape as shown in Fig. 9, or may be formed into a pointed shape at an acute angle as shown in Fig. 10. This configuration has the advantage of preventing the generation of vortexes caused by the fluid F discharged from the cooling fan colliding with the upper end 34 of the heat dissipation section 31. Furthermore, as shown in Fig. 10, a configuration may be adopted in which the first restricting wall closing the valley-shaped external space 36 is omitted.

[0047] REFERENCE SIGNS 1 heat sink 2 heat receiving base 3 heat dissipation promotion section 4 fluid supply section 5 case 21 contact surface 22 heat dissipation surface 30 internal space 31 heat dissipation section 32 heat dissipation plate 32a plate-shaped material 33 base end 34 tip end 35 through hole 36 external space 37 skin region 41 cooling fan 51 top plate 52 end plate 53 side plate 54 trapezoidal protrusion F cooling fluid X first direction Y second direction

Claims

1. A heat sink comprising: a metal heat-receiving base to which heat from an object to be cooled is transferred; a metal heat-dissipation promoting part fixed to the heat-receiving base and promoting the dissipation of the heat; and a fluid supply part that supplies a cooling fluid to the heat-dissipation promoting part, wherein the heat-dissipation promoting part has left and right base ends fixed to the heat-dissipating surface of the heat-receiving base, and comprises a plurality of heat-dissipating parts that are inverted V- or U-shaped in cross section and extend along a first direction on the heat-dissipating surface, and are arranged in a second direction perpendicular to the first direction, and a plurality of through-holes are formed in the plate surface of each of the heat-dissipating parts, connecting the internal space of the heat-dissipating part with the outside, and the fluid supply part circulates the fluid through at least one end of each of the heat-dissipating parts in the first direction and the plurality of through-holes as inlets and outlets, into the mountain-shaped internal space formed between each of the heat-dissipating parts and the heat-receiving base, and the heat from the heat-receiving base and the heat-dissipation promoting part is dissipated to the outside by the fluid.

2. A heat sink as described in claim 1, wherein each of the heat dissipation sections comprises a pair of left and right heat dissipation plates extending along the first direction of the heat dissipation surface, and the tip ends of the two heat dissipation plates abut or are close to each other so as to form an inverted V-shape or an inverted U-shape in cross section.

3. A heat sink as described in claim 1 or 2, wherein a first regulating wall that regulates the flow of the fluid by blocking the space between the heat dissipation sections arranged adjacent to each other in the second direction is provided at the end of the heat dissipation promotion section in the first direction.

4. A heat sink according to claim 1 or 2, further comprising a second restriction wall that closes the end of said heat dissipation promotion portion in said second direction to restrict the flow of said fluid.

5. A heat sink as described in claim 2, in which a pair of heat sinks are formed by cutting a lotus-type porous metal molding having multiple pores extending in one direction formed by a metal solidification method in a direction intersecting the direction in which the pores extend, and the base ends of the pair of heat sinks are fixed to the heat sink surface at a fixed interval.

6. A heat sink as described in claim 1, in which the heat dissipation section is formed by bending a flat metal heat dissipation plate made by cutting a lotus-type porous metal molding having multiple pores extending in one direction, formed by a metal solidification method, in a direction intersecting the direction in which the pores extend.

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