JP6064191B2 - Heat sink and heat sink manufacturing method - Google Patents

Description

  The present invention relates to a heat sink excellent in heat dissipation and easy to manufacture and a method of manufacturing the heat sink.

  In various devices such as large-scale integrated circuits (LSIs), ICs, and power transistors, and electronic devices equipped with these devices, the amount of heat generated during operation increases as the output of the devices increases. If the generated heat cannot be sufficiently dissipated, the capability of the device is reduced, and there is a risk of delaying responsiveness and malfunction of the electronic device. As one means for solving this, it is required to efficiently dissipate the increasing amount of heat.

  In recent years, with the miniaturization of various devices and the miniaturization of electronic devices, there has been a demand for more efficient heat dissipation. In order to efficiently dissipate heat, a configuration in which a heat sink is provided on the device itself is not sufficient, and it is necessary to perform cooling using a heat sink having a larger heat radiation area.

  In order to improve the performance of the heat sink, the surface area of the heat radiating surface is made wide, and this structure is generally a structure in which a plurality of plates called fins are erected in parallel on the surface of the metal plate Alternatively, a configuration in which a plurality of rod-like protrusions are erected so as not to contact each other is employed.

  The most common heat sink is manufactured by molding. In mold molding, the mold is usually manufactured by injecting a material into a mold having a large number of irregularities. Therefore, for example, in the case where a large number of irregularities formed by a molding die are configured in a small irregular shape, or when the interval between the irregularities is configured narrow, the injected material is provided with a large number of irregularities. It may be difficult to peel from the mold as it is.

  In addition, a heat sink having a large number of fins and a large number of rod-shaped protrusions has been conventionally produced by extrusion molding performed by applying high pressure to a metal material. However, in order to form a large number of fins and rod-shaped projections by extrusion molding, especially when the interval between adjacent fins and the interval between adjacent rod-shaped projections are made narrow, the pressing force for extruding the metal material As a result, a very high pressing force has to be used, and there is a problem in that the size of the extrusion apparatus is increased and the manufacturing cost is increased.

  As a manufacturing method for solving such problems, a projection is formed by pressing one surface of the metal plate with a pressing tool such as a punch and raising the other surface side of the metal plate. A method has been proposed. As a manufacturing method for forming protrusions on the surface opposite to the surface pressed by the pressing tool, a radiator and its manufacturing method (see Patent Document 1), a protrusion structure in a metal plate, and a protrusion processing method (see Patent Document 2). Etc. have been proposed.

  In the inventions described in Patent Document 1 and Patent Document 2, a concave portion that becomes a mark pressed by the punch is formed on the surface of the metal plate on which the punch is press-fitted. When a heat sink is manufactured using a manufacturing method for forming protrusions using such a punch, the contact area between the component to be cooled and the heat sink is reduced by the recess left on the surface on which the punch is press-fitted. It will be. Moreover, since the thermal conductivity of the air present in the recess is low, there arises a problem that the heat dissipation efficiency of the heat sink as a whole is lowered.

  In order to solve such a problem that the heat dissipation efficiency of the heat sink as a whole is lowered, the applicant of the present application has already proposed an embossed metal plate and a manufacturing method thereof (see Patent Document 3). In the invention of Patent Document 3, a large number of rod-shaped members are press-fitted into one surface of the metal plate, and the member constituting the metal plate is protruded from the surface opposite to the surface into which the rod-shaped member is pressed, It is the structure which forms many protrusions.

  In this invention, a large number of protrusions made of the same material as the metal plate can be formed on the surface opposite to the surface into which the rod-shaped member is press-fitted, and when a die is used on the surface into which the rod-shaped member is pressed. It is possible to leave the press-fitted rod-shaped member without causing such a recess. As a result, the bar-shaped member is disposed on the contact surface with the member to be cooled, so that the contact area between the heat sink and the member to be cooled is not reduced. And the heat dissipation effect as a heat sink can be increased.

  Moreover, as the metal constituting the rod-shaped member, a metal having a material different from that of the metal plate can be used. Therefore, a metal having a higher thermal conductivity than the metal plate can be used as the metal of the rod-shaped member. it can. As a result, a bar-shaped member made of a metal having a high thermal conductivity can be disposed on the surface that contacts the member to be cooled, so that the heat conduction speed is increased to increase the heat radiation efficiency. Can do. And a heat sink with a high heat dissipation effect can be obtained.

  In addition, when the metal plate itself is made of a metal having a high thermal conductivity, a large amount of expensive metal must be used, which increases the price of the heat sink. However, when a metal having a high thermal conductivity is used only for the rod-like member as in Patent Document 3, it is possible to use an expensive metal for only a part of the metal, thus suppressing an increase in the price as a heat sink. I can keep it.

JP-A-10-511168 JP 2003-230931 A JP 2011-251338 A

  When the rod-shaped member is press-fitted into the metal plate as in the invention of Patent Document 3, a gap is formed between the rod-shaped member and the surface of the metal plate into which the rod-shaped member is press-fitted. In particular, when the press-fitting of the bar-shaped member into the metal plate is performed in order, the gap formed around the bar-shaped member previously press-fitted by the bar-shaped member press-fitted later tends to widen.

  That is, the metal flow also occurs around the rod member that has been press-fitted by the rod member that has been press-fitted later. Then, around the rod-shaped member press-fitted first, a metal flow is generated while being pulled toward the rod-shaped member that has been press-fitted later.

  As a result, the gap generated around the rod-shaped member press-fitted in the metal plate tends to be further expanded by the rod-shaped member pressed later. As described above, when the bar-shaped member is press-fitted later at the position adjacent to the bar-shaped member that has been press-fitted in advance, the gap generated around the bar-shaped member that has been press-fitted earlier is further expanded.

In the invention of Patent Document 3, since the press-fitted rod-shaped member is arranged on the back side of the heat sink, even if a gap is formed between the rod-shaped member and the surface of the metal plate, The influence on the heat dissipation effect in the heat sink is small. However, in the case of a configuration in which the rod-shaped member is protruded from the surface side of the heat sink, it is necessary to solve the gap problem in order to further improve the heat dissipation effect as the heat sink.

  The present invention solves the problem of the gap generated around the press-fitted rod-shaped member, and an object of the present invention is to further improve the invention of Patent Document 3. In addition, in a configuration in which a rod-shaped member (in the present invention, a protrusion) is erected from the surface side of the heat sink, it is an object to provide a heat sink with high heat dissipation efficiency and low manufacturing cost, and a method for manufacturing the heat sink. Yes.

The subject of this invention can be achieved in the heat sink as described in Claims 1-4, and the manufacturing method of the heat sink as described in Claims 5 and 6.
That is, in the heat sink of the present invention, a large number of rod-shaped protrusions made of a metal material are press-fitted onto the surface of the metal substrate, and the protrusions are separated from each other with one end protruding from the surface of the metal substrate. Arranged,
When the other end of each projection is press-fitted from the surface side of the metal substrate, a gap formed around each projection on the surface side of the metal substrate covers at least the other end side. The most important feature is that the coated metal is filled with molten and solidified metal.

In addition, the heat sink of the present invention is mainly characterized in that the melting point of the coated metal is lower than the melting point of each protrusion and the melting point of the metal substrate.
Furthermore, the heat sink according to the present invention is mainly characterized in that the protrusion is made of a metal material having a higher thermal conductivity than the metal substrate.

  Furthermore, in the heat sink according to the present invention, the press-fitting of each of the protrusions causes the spiral groove formed in the other end of each of the protrusions to rotate toward the inside of the metal substrate while plastically deforming the metal substrate. The main feature is that it is a screw-in press.

In the heat sink manufacturing method of the present invention, from the surface side of the metal substrate, a large number of rod-shaped protrusions made of a metal material having a larger thermal conductivity than the metal substrate are press-fitted in a distant relationship with each other,
Using a protrusion whose at least the other end side of the protrusion is coated with a coating metal, and using a coating metal having a melting point lower than the melting point of each of the protrusions and the melting point of the metal substrate as the coating metal, Press fitting the other end of each projection into the surface of the metal substrate in a state where one end of each projection protrudes from the surface of the metal substrate;
Heating the covering metal of each projection pressed into the surface of the metal substrate, and when the projections were pressed into the metal substrate, occurred around the projections on the surface side of the metal substrate. Another most important feature is that the gap is filled with the molten coating metal and the molten coating metal filling the gap is solidified.

Further, in the heat sink manufacturing method of the present invention, a large number of rod-like protrusions constituting the heat sink are grouped into a plurality of sets, and each of the protrusions constituting one set is simultaneously applied to the metal substrate. Press-fitting, and then press-fitting into the metal substrate a plurality of the protrusions constituting the set to be next press-fitted adjacent to the first press-fitted set,
Repeating this in sequence, centering on the first press-fit group, adjacent to the previously press-fit group, and simultaneously pressing the plurality of protrusions constituting the next press-fit group into the metal substrate Is the main feature.

  As described above in the column of problems to be solved by the invention, when the protrusions are sequentially press-fitted into the surface side of the metal substrate, a gap is formed around the protrusions. And as this clearance gap, the clearance gap formed in the circumference | surroundings of the projection body press-fitted previously is comprised by the projection body press-fitted later, and the magnitude | size of a clearance gap is comprised more widely.

  Therefore, in the present invention, at least the other end side of each protrusion is covered with a covering metal. Then, after each protrusion is press-fitted into the surface of the metal substrate from the other end side, the coating metal is melted, and the gap is filled with the molten coating metal. After the gap is filled with the molten coating metal, the molten coating metal is solidified.

  As a method for coating the coating metal, for example, the projection metal can be coated with the coating metal by plating, coating, dipping, or the like. Alternatively, for example, the protrusion can be covered with a coating metal by covering the protrusion with a metal pipe or a metal collar. When covering the protrusion with the metal pipe or the metal collar, the protrusion can be covered before pressing into the metal substrate, or the protrusion can be covered after pressing into the metal substrate.

  By comprising in this way, the heat sink with which the clearance gap was filled with the covering metal can be obtained. By filling the gap with the covering metal, the heat conduction between the metal substrate and the protrusions is improved. In addition, the solidified coated metal can provide an adhesive effect between the protrusions press-fitted into the metal substrate and the metal substrate, and the fixing state of the protrusions with respect to the metal substrate can be improved.

  It is desirable to cover at least the other end portion of the protrusion to be press-fitted into the metal substrate as the portion of the protrusion to be coated with the coating metal, and coat the entire protrusion with the covering metal. However, in the case where a coated metal having a low thermal conductivity is coated, it is desirable to coat at least the portion around the protrusion facing the gap with the coated metal.

In the present invention, the coating metal may be configured so that the outer surface of the projection is coated with a metal layer. The melting point of the coating metal is the melting point of the metal material constituting each projection and the metal substrate. The melting point can be kept lower than the melting point of the metal material.
With this configuration, even when the entire metal substrate into which a large number of protrusions are press-fitted is heated, only the coated metal can be melted by adjusting the heating temperature. Then, the molten coating metal can be allowed to flow into the gap formed around each protrusion.

In the present invention, the protrusion can be configured using a metal material having a thermal conductivity larger than that of the metal substrate.
With this configuration, the amount of heat radiated from the protrusions can be increased, and the heat dissipation effect as a heat sink having a large number of protrusions can be enhanced.

  As the metal substrate, an aluminum material or an aluminum alloy material having a high thermal conductivity can be used. As the protrusions, it is also possible to configure the projection using an aluminum material or an aluminum alloy material as in the case of the metal substrate, which is more expensive than an aluminum material or an aluminum alloy material, but is a metal having a higher thermal conductivity, for example, , Copper or the like can be used. Moreover, as the covering metal, if the unit price is not taken into consideration, an expensive metal having high thermal conductivity such as gold or silver can be used. However, in consideration of the unit price, a tin material or a solder material may be used. it can.

  In the present invention, as a press-in method for press-fitting the protrusion into the metal substrate, a press-in method in which one end of the protrusion is pressed and the other end of the protrusion is mechanically pressed into the metal substrate can be employed. . In addition, a spiral groove is formed at the other end of the protrusion that is press-fitted into the metal substrate, and the spiral groove is screwed while rotating toward the inside of the metal substrate, thereby causing plastic deformation in the metal substrate. A press-fitting method in which the protrusion is press-fitted into the metal substrate can also be employed.

  In this way, in the present invention, a press-in method in which the protrusion is mechanically pushed directly into the metal substrate is adopted, or a press-in method in which the protrusion is screwed in while causing plastic deformation in the metal substrate. You can also. Then, the protrusion can be firmly fixed to the metal substrate.

  In the present invention, a large number of rod-shaped protrusions constituting the heat sink can be grouped into a plurality of groups. Then, a plurality of sets can be sequentially press-fitted into the metal substrate in succession to the first press-fitted set and the next press-fitted set adjacent to the first press-fitted set. At this time, when each set is press-fitted into the metal substrate, a plurality of protrusions constituting each set can be simultaneously press-fitted into the metal substrate.

  When one set is first press-fitted into the metal substrate, the next set to be pressed into the metal substrate is one set adjacent to one side of the first press-fit set or both sides of the first press-fit set. Two adjacent sets can be pressed into the metal substrate. When the two sets are pressed into the metal substrate, the two sets can be pressed into the metal substrate at the same time.

  When one set is press-fitted into one side of the first set following the first set, the next press-in set may be press-fitted into the metal substrate adjacent to the other side that has been press-fitted first. it can. The next press-fit group can be press-fitted into the metal substrate adjacent to the press-fit group adjacent to one side of the first press-fit group.

  In addition, when two sets are press-fitted into the metal substrate following the first press-fitted set, the next two sets of press-fitting are adjacent to the two sets that are press-fitted after the first press-fit set. Can be press-fitted into.

  By repeating this in sequence, it is possible to press-fit the next press-fit group adjacent to the previously press-fit group, with the first press-fit group as the center.

  By repeatedly performing such press-fitting one after another, a large number of protrusions can be press-fitted into the metal substrate. By manufacturing the heat sink in this manner, the size of the gap formed around each protrusion is smaller than that of the surface of the metal substrate, compared to when each protrusion is randomly pressed into the metal substrate. It is possible to prevent the size of each part from becoming different.

Moreover, a large number of protrusions can be efficiently created, and the heat sink can be manufactured efficiently. As a result, the manufacturing cost of the heat sink can be reduced.
Moreover, since the amount of the molten coating metal that flows into the gap to fill the gap can be made substantially uniform over the entire surface of the metal substrate, the thickness of the coating layer of the coating metal on each protrusion can be reduced. Even if it is formed uniformly, it can be surely prevented that the gap is not completely filled with the molten coating metal.

Various arrangements such as a lattice arrangement, a staggered arrangement, a radial arrangement, and a helical arrangement can be adopted as the arrangement of the multiple protrusions press-fitted into the metal substrate. Moreover, it is also possible to adopt a configuration in which a plurality of protrusions are made into one lump, and the plurality of lump projections are scattered and arranged on a metal substrate like an island.

  In addition, the multiple protrusions can be arranged at equal intervals or at irregular intervals. And as an arrangement configuration of a large number of protrusions press-fitted into the metal substrate, an appropriate arrangement configuration suitable for the application can be adopted according to the application using the heat sink.

  A large number of protrusions can be continuously manufactured by cutting a long rod for each predetermined dimension. And an elongate rod can be formed by, for example, extruding a metal material from a nozzle. By comprising in this way, a protrusion can be manufactured efficiently.

  In addition, the spiral groove formed on the other end of the protrusion may be formed by cutting the other end of the protrusion, or may be formed by rolling the other end. It can also be formed. Alternatively, a protrusion having a spiral groove can be formed by casting. Furthermore, the spiral groove can be formed at the other end of the protrusion by using another forming method for forming the spiral groove.

It is a perspective view which shows a heat sink. (Example) It is II-II sectional drawing of FIG. (Example) It is a schematic sectional drawing which shows the cross section of the press-fitted protrusion. (Example) It is a schematic sectional drawing which shows the clearance gap formed around a projection body. (Example) It is a schematic sectional drawing which shows the state with which the coating metal was filled into the clearance gap formed in the circumference | surroundings of the protrusion. (Example) It is a perspective view of the heat sink which shows the other arrangement | positioning relationship of a protrusion. (Example) It is a schematic sectional drawing which shows the manufacturing method of a heat sink. (Example) It is a schematic sectional drawing which shows the other manufacturing method of a heat sink. (Example)

  Preferred embodiments of the present invention will be specifically described below with reference to the accompanying drawings. As the heat sink according to the present invention, any shape and configuration that can solve the problems of the present invention can be adopted.

  Further, the heat sink according to the present invention is not limited to a heat sink used for an electronic device or the like, and is preferably used as a heat sink used in a place where it is necessary to efficiently dissipate a heat source in a vehicle, a construction machine, a ship, or the like. It can be applied. Therefore, the present invention is not limited to the configurations of the embodiments described below, and various modifications are possible.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of a heat sink 1 according to the present invention. The heat sink 1 has a configuration in which a large number of protrusions 3 are press-fitted into the surface 2 a of the metal substrate 2.

  1 shows the configuration of the heat sink 1 configured by press-fitting a large number of protrusions 3 on the surface 2a of the metal substrate 2, the configuration related to the size and shape of the heat sink 1 according to the present invention, The number of the protrusions 3 pressed into the metal substrate 2 and the cross-sectional shape of the protrusions 3 are not limited to the configuration shown in the illustrated example. An appropriate size and shape, the number of press-fitted protrusions 3 and a cross-sectional shape can be set according to the object using the heat sink 1.

  Further, FIG. 1 shows a configuration in which a large number of protrusions 3 are arranged in a lattice shape, but a configuration in which a large number of protrusions 3 are arranged in a staggered manner as shown in FIG. . As the arrangement configuration of the plurality of protrusions 3, any arrangement configuration can be adopted as long as the arrangement configuration can enhance the heat dissipation effect as the heat sink 1.

  That is, various arrangements of the protrusions 3 press-fitted into the metal substrate 2 include various arrangements such as a lattice arrangement, a staggered arrangement, a radial arrangement, and a helical arrangement. An arrangement can be employed. It is also possible to arrange a plurality of projections 3 in a lump, and to arrange the plurality of projections in a lump on the metal substrate 2 like islands.

  In addition, the multiple protrusions 3 can be configured to be arranged at regular intervals or can be configured to be arranged at irregular intervals. Thus, as the arrangement configuration of the multiple protrusions 3 press-fitted into the metal substrate 2, an appropriate arrangement configuration suitable for the application can be adopted according to the application in which the heat sink 1 is used.

  In addition, as the shape of the protrusion 3, FIG. 1 shows a cylindrical shape, that is, the protrusion 3 has a circular cross-sectional shape. The present invention is not limited to this configuration, and the present invention can be suitably applied even when the cross-sectional shape of the protrusion is a protrusion having an elliptical shape, a rectangular shape, a star shape, or the like.

  Moreover, although the shape in the height direction of the protrusion 3 press-fitted into the metal substrate 2 is shown as an example of a uniform cross-sectional shape, the cross-sectional shape changes along the height direction. Even the protrusion formed in the shape is a protrusion formed in a shape having a plurality of protruding pieces protruding outward on the outer circumferential surface of the protrusion 3 in the height direction. Also, the protrusion 3 according to the present invention can be suitably applied.

  In order to press-fit a large number of protrusions 3 into the metal substrate 2 at the same time, a large press-fitting device is required. Therefore, the present invention employs a method in which a large number of protrusions 3 are pressed into the metal substrate 2 without using a large press-fitting device.

  That is, the case of manufacturing the configuration of the heat sink 1 shown in FIG. 1 will be described. First, five protrusions 3a arranged in a single row are simultaneously press-fitted, and then arranged alongside the five protrusions 3a. Five protrusions 3b and 3c arranged in a single row are simultaneously press-fitted. Thereafter, the five protrusions 3d and 3e arranged in a single row are press-fitted at the same time adjacent to the protrusions 3b and 3c, so that the 25 protrusions 3 are press-fitted in a lattice form of five columns and five rows. The heat sink 1 is configured.

  First, the five protrusions 3a arranged in a single row are simultaneously press-fitted, then the five protrusions 3b arranged in a single row are press-fitted, and then the five protrusions 3c arranged in a single row are press-fitted. Then, the protrusions 3d arranged in a single row and the projections 3e arranged in a single row can be press-fitted in order in the following order.

  As shown in FIG. 2, which is a cross-sectional view taken along the line II-II in FIG. 1, the protrusions 3 (3a to 3e) press-fitted to the surface 2a side of the metal substrate 2 do not press-fit the entire length of each protrusion 3. The other end 4 side of each protrusion 3 is press-fitted from the surface 2a side of the metal substrate 2, and the one end side is erected from the surface of the metal substrate 2.

  When the heat sink 1 is manufactured by the mechanical press-fitting method, it is desirable that the hardness of the metal material constituting the protrusion 3 is higher than the hardness of the metal material constituting the metal substrate 2, but the metal is the same metal material. The substrate 2 and the protrusion 3 can also be configured. Further, in order to enhance the heat dissipation effect as the heat sink 1, it is preferable to use a metal material having high thermal conductivity as the metal material constituting the metal substrate 2 and the protrusion 3.

  In consideration of such conditions, the metal substrate 2 is made of an aluminum material or an aluminum alloy, and the protrusion 3 is made of a copper material or a copper alloy having a higher thermal conductivity and hardness than aluminum. be able to. Then, the press-fitting of the protrusions 3 into the metal substrate 2 can be improved, and the heat dissipation effect as the heat sink 1 can be further enhanced.

  Although the description has been given of the configuration in which the metal material constituting the metal substrate 2 and the metal material constituting the protrusion 3 are different from each other, the metal substrate 2 and the protrusion 3 should be configured using the same metal material. You can also.

  7 and 8 show a configuration example of a press-fitting method in which five protrusions 3 are simultaneously press-fitted into the surface 2a of the metal substrate 2. FIG. FIG. 7 shows a press-fitting method in which the metal constituting the metal substrate 2 does not protrude from the back surface 2b side of the metal substrate 2 when the protrusion 3 is press-fitted into the metal substrate 2. FIG. 8 shows a press-fitting method in which when the protrusion 3 is press-fitted into the metal substrate 2, the metal constituting the metal substrate 2 protrudes from the back surface 2b of the metal substrate 2 to form the protruding portion 18. .

  In the press-fitting method shown in FIGS. 7 and 8, for example, an aluminum plate having a Vickers hardness of about Hv 40 to 70 is used as the metal substrate 2, and the protrusion 3 is Vickers more than the aluminum plate using the metal substrate 2. The structural example using the copper material with high hardness is shown. The protrusion 3 is a cylindrical copper column having a diameter of 1.2 mm and a height of 2 mm.

  Then, a coating metal can be coated on the other end 4 (see FIG. 2) side of the protrusion 3 that is press-fitted into the metal substrate 2. As a covering metal, it can coat | cover using a tin material, a solder material, etc. previously. As a coating method for coating the coating metal, for example, the projection metal can be coated with the coating metal by plating, coating, dipping, or the like.

  Alternatively, for example, the protrusion can be covered with a coating metal by covering the protrusion with a metal pipe or a metal collar. When covering the protrusion 3 with a metal pipe or metal collar, the protrusion 3 may be covered before the metal substrate 2 is press-fitted, or the protrusion 3 may be covered with the protrusion 3 after the protrusion 3 is press-fitted into the metal substrate 2. You can also.

When the metal substrate 2, the protrusion 3 and the covering metal are provided with the above-described configuration, the protrusion 3 is press-fitted into the metal substrate 2 by using a pressing force of about 120 kg or more per protrusion 3. can do.
The configuration of the metal substrate 2, the projection 3 and the covering metal, and the pressing force against the projection 3 shown in FIGS. 7 and 8 are examples, and the present invention is not limited to the above configuration. Absent.

  First, the mechanical press-fitting method according to FIG. 7 will be described. As shown in FIG. 7A, the metal substrate 2 is placed on the upper surface 15 a of the fixed lower mold 15. The upper surface of the lower mold 15 is formed flat, and the back surface 2b of the metal substrate 2 can be supported in a surface contact state. An intermediate die 13 having a plurality of through holes 14 is disposed on the lower die 15, and the intermediate die 13 is arranged to be slidable in the vertical direction toward the lower die 15. In each through hole 14, a protrusion 3 is housed.

  An upper die 11 that is slidable in the vertical direction is arranged on the upper portion of the middle die 13, and the upper die 11 includes a plurality of plungers 12 corresponding to a plurality of through holes 14 formed in the middle die 13. However, it is arranged so as to slide integrally with the upper die 11. The middle mold 13 can be lowered by inserting each plunger 12 into the through hole 14 and lowering and pushing the upper mold 11 down.

  Although it has been described that the middle mold 13 slides in the vertical direction in conjunction with the upper mold 11, the middle mold 13 can be slid in the vertical direction independently of the upper mold 11.

Then, from the state in which the lower surface 13a of the middle mold 13 is in contact with the surface 2a of the metal substrate 2 and the metal substrate 2 is sandwiched between the middle mold 13 and the lower mold 15, as shown in FIG. When 11 is further lowered, each plunger 12 can slide in the respective through hole 14 and further fall. Each protrusion 3 is press-fitted from the surface 2 a side of the metal substrate 2 by the pressing force of each plunger 12 that is in contact with each protrusion 3.

  At this time, since movement of the metal substrate 2 in the vertical direction is restricted by the middle mold 13 and the lower mold 15, the deposit expanded by the press-fitting of the protrusions 3 is directed to the front, rear, left and right directions of the metal substrate 2. Become. That is, the expanded deposit flows in the front / rear / left / right direction of the metal substrate 2 by the metal flow, and the flowed metal spreads in the front / rear / left / right direction of the metal substrate 2. The outer shape of the metal substrate 2 is larger than that before the plurality of protrusions 3 are press-fitted.

  As shown in FIG. 7C, when the middle mold 13 and the upper mold 11 are pulled up after the plurality of protrusions 3 are press-fitted into the metal substrate 2, the metal substrate 2 into which the plurality of protrusions 3 are press-fitted can be obtained. . In order to subsequently press-fit the plurality of protrusions 3 into the metal substrate 2, the position of each plunger 12 provided on the upper mold 11 is configured to move to a position where the next protrusion 3 is press-fitted. be able to.

  When the protrusions 3b and 3c are press-fitted at the same time after the protrusion 3a shown in FIG. 4 is press-fitted, the upper mold 11 provided with the plunger 12 for the protrusion 3b and the plunger 12 for the protrusion 3c are provided. A pair of upper molds 11 provided may be provided, and the respective upper molds 11 and 11 may be configured to move in conjunction with the directions away from each other along the front and back direction of the paper surface in FIG. .

  Further, when the protrusions 3b and 3c are sequentially pressed after the protrusion 3a shown in FIG. 4 is press-fitted, the upper mold 11 provided with the plunger 12 for the protrusion 3a is shown in FIG. It can be set as the structure which moves along the front and back direction of a paper surface.

  Then, after press-fitting the protrusion 3a shown in FIG. 4, depending on whether the protrusions 3b and 3c are simultaneously press-fitted or individually press-fitted, the plungers 12 or upper The above-described press-fitting operation can be performed by moving the plunger 12 of the mold 11 to a position corresponding to the press-fitting of the protrusions 3b and 3c to be press-fitted next. By repeating this press-fitting operation as many times as necessary, a heat sink 1 having a desired number of protrusions 3 can be obtained.

  In addition to the press-fitting method, for example, a press-fitting method in which the position of the metal substrate 2 placed on the lower mold 15 is moved and the plurality of protrusions 3 are sequentially press-fitted can be employed. Further, the plurality of protrusions 3 can be press-fitted into the metal substrate 2 by using a conventionally known press-fitting method.

  Next, the mechanical press-fitting method shown in FIG. 8 will be described. In FIG. 8, about the member of the same structure as the member used in FIG. 7, the description of the member is abbreviate | omitted by using the same member code | symbol. As shown in FIG. 8A, the metal substrate 2 is placed on the upper surface 20 a of the fixed lower mold 20. The upper surface of the lower mold 20 is formed flat, and the back surface 2b of the metal substrate 2 can be supported in a surface contact state. A plurality of through holes 16 are formed in the lower mold 20, and a receiving jig 17 is slidably disposed in each through hole 16.

  As shown in FIG. 8A, the metal substrate 2 is placed on the upper surface 20 a of the lower mold 20. At this time, the upper surface of the receiving jig 17 disposed in each through-hole 16 of the lower mold 20 is in contact with the back surface 2b of the metal substrate 2.

As shown in FIG. 8B, when each protrusion 3 is pressed by a plurality of plungers 12 provided on the upper mold 11, each protrusion 3 is press-fitted from the surface 2 a side of the metal substrate 2. At this time, on the back surface 2 b side of the metal substrate 2, the metal constituting the metal substrate 2 protrudes downward along with the press-fitting of the protrusions 3 to form the protruding portion 18. Each receiving jig 17 is provided so that the protruding amount of each protruding portion 18 becomes an equal protruding amount, and each receiving jig 17 is integrated according to the protruding amount of each protruding portion 18. It is configured to be able to slide in the vertical direction.

  As shown in FIG. 8C, after a plurality of protrusions 3 are press-fitted onto the front surface 2a side of the metal substrate 2 and a plurality of protrusions 18 are projected onto the back surface 2b side, the middle mold 13 and the upper mold 11 are mounted. The metal substrate 2 into which the plurality of protrusions 3 are press-fitted can be obtained by pulling up and pushing up the receiving jig 17. At this time, one end portion side of each protrusion 3 is arranged in a state of being erected from the surface 2a of the metal substrate 2.

  In the same manner as the press-fitting method in FIG. 7, the upper die 11 is moved along the front and back directions of the paper surface as many times as necessary for the metal substrate 2 press-fitted with the plurality of protrusions 3 formed in this way. Or by moving the mounting position of the metal substrate 2 with respect to the plurality of plungers 12 provided on the upper die 11, the heat sink 1 having the desired number of protrusions 3 can be obtained.

In order to allow a desired number of protrusions 3 to be press-fitted into the metal substrate 2, the lower mold 20 has a number of through holes 16 corresponding to the total number of protrusions 3 to be finally press-fitted. . As the receiving jig 17, the receiving jigs 17 are disposed in all the through holes 16, or only the through holes 16 arranged at positions corresponding to the plungers 12 of the upper mold 11 are received. A jig 17 can also be provided.
Even if the protrusion 18 is formed on the metal substrate 2, the protrusion 18 can be stored in the through hole 16, so that the back surface 2b of the metal substrate 2 is in surface contact with the upper surface 20a of the lower mold 20. It can be placed in a state.

  In the press-fitting method shown in FIG. 8, even if the protrusion 3 is press-fitted into the metal substrate 2, the deposit that has expanded as a result of the press-fitting is consumed as the protruding portion 18 from the back surface 2 b of the metal substrate 2. become. For this reason, the press-fitting method shown in FIG. 8 has a slightly more complicated configuration than the press-fitting method shown in FIG. 7, but the outer dimensions of the metal substrate 2 are the same before and after the protrusion 3 is press-fitted into the metal substrate 2. There is a merit that the change that occurs is small.

  And as shown in FIG.8 (d), the heat sink 1 without the protrusion part 18 can be obtained by removing the protrusion part 18 which protruded from the back surface 2b of the metal substrate 2. FIG. Further, when the heat sink 1 is used in a shape having the protruding portion 18, it is not necessary to delete the protruding portion 18.

  Next, using FIG. 3 to FIG. 5, a gap formed around the projection 3 pressed into the surface 2 a of the metal substrate 2, and a coating metal that covers this gap on the other end 4 side of the projection 3 The structure filled with the melted and solidified metal 6 will be described.

  3 to 5, the description will be made using the protrusions 3 a to 3 c in the order of press-fitting into the metal substrate 2. That is, the protrusion 3a is first press-fitted, and then the protrusions 3b and 3c are press-fitted at the same time. Instead of simultaneously press-fitting the protrusions 3b and 3c, it is also possible to press-fit the protrusion 3b and then press-fit the protrusion 3c. Each of the protrusions 3a to 3c shown in FIGS. 3 to 5 is representative of a plurality of protrusions 3a to 3c arranged in a horizontal single row as shown in FIGS. Further, in order to illustrate the shape of the gap 5 in an easy-to-understand manner, the size of the gap 5 is illustrated in an exaggerated state.

As shown in FIG. 3, when the protrusion 3a is press-fitted into the surface 2a of the metal substrate 2 and the other end 4 side of the protrusion 3a is inserted into the metal substrate 2, the periphery of the protrusion 3a and the metal substrate 2 A gap 5a is formed between the surface 2a side. It is considered that the gap 5a is formed when the protrusion 3a is press-fitted from the surface 2a of the metal substrate 2 and the metal constituting the metal substrate 2 flows along with the press-fitting of the protrusion 3a. .
The gap 5a is formed in a shape in which the periphery is slightly raised, such as the outer peripheral edge of the crater.

  As shown in FIG. 4, when the protrusions 3b and 3c are press-fitted into the surface 2a of the metal substrate 2 adjacent to the protrusion 3a, the periphery of the protrusions 3b and 3c and the surface 2a side of the metal substrate 2 are The gaps 5b and 5c are also formed between them. The gap 5b is formed around the protrusions 3b and 3c on the side of the protrusion 3a that has been press-fitted first, and the gap 5c is formed around the protrusions 3b and 3c at a position away from the protrusion 3a that has been press-fitted previously. .

  Then, among the gaps 5a formed around the protrusions 3a that have been press-fitted first, the gaps 5a that have been formed on the protrusions 3b and 3c that have been press-fitted later are accompanied by the press-fitting of the protrusions 3b and 3c. As a result, a metal flow is generated and pulled on the protrusion 3b side and the protrusion 3c side, and the size of the gap 5a is increased. Further, as the metal flows from the protrusion 3a side to the protrusion 3b side and the protrusion 3c side, the gaps 5b and 5c formed around the protrusions 3b and 3c are larger in the gap 5b than in the gap 5c. It tends to be somewhat narrow.

  Depending on the distance between the protrusion 3a and the protrusions 3b, 3c, the external dimensions of the protrusion 3a and the protrusions 3b, 3c, the material of the protrusions 3a, 3b, 3c, the material of the metal substrate 2, etc. The sizes of 5a to 5c may be almost unchanged, or the gaps 5b and 5c formed around the protrusions 3b and 3c may be the same size. .

  Thus, when the protrusions 3a, 3b, 3c are press-fitted into the surface 2a side of the metal substrate 2, gaps 5 (5a-5c) are formed around the press-fitted protrusions 3a, 3b, 3c. It will be done.

  In the embodiment according to the present invention, the remaining protrusions 3b and 3c are press-fitted in such a manner that the remaining protrusions 3b and 3c are sequentially pressed away from the protrusion 3a from the side closer to the first press-fitted protrusion 3a. The portion of the metal substrate 2 where the metal is pressed is a portion where plastic deformation is not so much caused by the press-fitting of the protrusions. Therefore, the remaining protrusions 3b and 3c can be easily press-fitted from the surface 2a side of the metal substrate 2.

  If the protrusion 3b and the protrusion 3c in FIG. 4 are press-fitted and then the protrusion 3a is press-fitted into a portion between the protrusion 3b and the protrusion 3c, the gap between the protrusion 3b and the protrusion 3c. This portion is in a state where the metal is hardened due to plastic deformation by press-fitting the protrusion 3b and the protrusion 3c, so that the protrusion 3a press-fitted into the metal-hardened portion is press-fitted into the metal substrate 2 by a desired amount. Requires a large pressing force. However, in the present invention, since the next protrusion is press-fitted into a site where plastic deformation has not occurred so much by the previously press-fitted protrusion, the pressing force for pressing the protrusion is so large. Do not need.

  Although not shown, the other end 4 side of each of the protrusions 3a to 3c is covered with a coating metal. As the other end 4 side where the coating metal is coated, a region from the surface 2a of the metal substrate 2 to a portion slightly above the press-fitted protrusion 3 can be set. The thickness of the coated metal to be melted and solidified and the area to be coated can be configured to be an amount that can fill the gap 5.

When the projections 3a to 3c are press-fitted from the surface 2a side of the metal substrate 2 and then heated so that the coating metal is melted, the coating metal is melted and can flow into the gaps 5a to 5c. When the molten coated metal flowing into the gaps 5a to 5c is solidified, the gaps 5a to 5c are filled with the melted and solidified metal 6 as shown in FIG.
In FIG. 5, the shapes of the gaps 5 a to 5 c and the state of the melted and solidified metal 6 are illustrated in an exaggerated state for easy understanding.

  As shown in FIG. 5, the gaps 5a to 5c are melted and solidified and filled with the metal 6, so that the gaps 5a are covered with a metal having higher thermal conductivity than the air layer existing in the gaps 5a to 5c. ˜5c can be filled, and the heat sink 1 without gaps 5a to 5c can be obtained. In this way, a heat sink with high heat dissipation efficiency and low manufacturing cost can be obtained. Further, the melted and solidified coated metal can also exhibit an adhesion function for further strengthening the fixing state between the protrusion 3 and the metal substrate 2.

  In the above description, the configuration in which each protrusion 3 is directly press-fitted into the metal substrate 2 has been described, but as the press-fitting of each protrusion 3 according to the present invention, in addition to the direct press-fitting method, the protrusion 3 It is also possible to employ a press-fitting method in which a spiral groove (not shown) is formed in the other end portion 4 and the spiral groove is screwed while rotating toward the inside of the metal substrate 2.

  In this press-fitting method by twisting, the protrusion 3 can be press-fitted into the metal substrate 2 by twisting the protrusion 3 while causing plastic deformation of the metal substrate 2. The spiral groove (not shown) formed in the other end 4 of the protrusion 3 may be formed by cutting the other end 4 of the protrusion 3 or may be transferred to the other end 4. It is also possible to form a spiral groove. Alternatively, the protrusion 3 having a spiral groove can be formed by casting. Furthermore, the spiral groove can be formed in the other end portion 4 of the protrusion 3 by using another forming method for forming the spiral groove.

  In this way, in the present invention, it is possible to adopt a press-fitting method in which the protrusion 3 is mechanically pushed directly into the metal substrate 2, or press-fitting the protrusion 3 while causing plastic deformation in the metal substrate 2. The method can also be adopted. Then, the protrusion 3 can be firmly fixed to the metal substrate 2.

  As a method of screwing the protrusions 3 into the metal substrate 2, a screwing method in which the protrusions 3 are screwed one by one, or a screwing method in which a plurality of the protrusions 3 are simultaneously screwed in is employed. You can also.

  In order to simultaneously screw a plurality of protrusions 3 at the same time, the respective protrusions 3 to be screwed at the same time are held at the same time so as not to interfere with each other between the respective screwing tools that give rotation and pressing force. It is necessary to widen the interval between the protrusions 3 to be screwed. Then, by positioning the plurality of protrusions 3 to be simultaneously screwed in the space between the screwed protrusions 3, the plurality of protrusions 3 are sequentially arranged in a state where the interval between the adjacent protrusions 3 is narrowed. Can be screwed in.

  In the present invention, compared to the case where the entire heat sink 1 is formed of the same metal having a high thermal conductivity, only the protrusion 3 can be configured using a metal having a higher thermal conductivity than the metal substrate 2. Therefore, the heat sink 1 can be manufactured at low cost, and the heat sink 1 having high heat dissipation efficiency can be configured.

  Further, in the present invention, when the protrusions 3 are press-fitted into the metal substrate 2, a large number of the protrusions 3 are press-fitted more efficiently than a method of manufacturing a heat sink by pressing a large number of protrusions 3 at a time. Therefore, the pressing force required for press-fitting can be configured low. Thereby, the manufacturing cost of the heat sink 1 can be reduced. For this reason, the present invention can greatly contribute to technical fields such as a heat dissipation device.

In the above description, in the configuration in which a plurality of protrusions 3 are simultaneously press-fitted into the metal substrate 2, the gap 5 formed around the press-fitted protrusions 3 is covered with the coated metal that has covered the protrusions 3. The configuration for filling with molten metal was explained. However, even when the protrusions 3 are pressed into the metal substrate 2 one by one, a gap 5 is formed around the pressed protrusions 3. Therefore, the present invention is not limited to the case where a plurality of protrusions 3 are simultaneously press-fitted into the metal substrate 2, and is also suitable for the case where the protrusions 3 are pressed into the metal substrate 2 one by one. Can be applied.

  The present invention can be suitably applied to the manufacture of a heat sink.

DESCRIPTION OF SYMBOLS 1 ... Heat sink, 2 ... Metal substrate, 3, 3a-3e ... Projection body, 5, 5a, 5b, 5c ... Clearance, 6 ... Melted and solidified metal, 11 ... Above Mold, 12 ... Plunger, 13 ... Medium mold, 15 ... Lower mold, 18 ... Projection, 20 ... Lower mold.

Claims (6)

A large number of rod-shaped protrusions made of a metal material are press-fitted onto the surface of the metal substrate,
Each of the protrusions is disposed apart from each other with one end side protruding from the surface of the metal substrate,
When the other end of each projection is press-fitted from the surface side of the metal substrate, a gap formed around each projection on the surface side of the metal substrate covers at least the other end side. A heat sink, wherein the coated metal is filled with a molten and solidified metal.   The heat sink according to claim 1, wherein a melting point of the covering metal is lower than a melting point of each of the protrusions and a melting point of the metal substrate.   The heat sink according to claim 1, wherein the protrusion is made of a metal material having a higher thermal conductivity than the metal substrate.   The press-fitting of each protrusion is a press-fitting that is screwed while rotating the spiral groove formed in the other end of each protrusion toward the inside of the metal substrate while plastically deforming the metal substrate. The heat sink according to any one of claims 1 to 3. A method of manufacturing a heat sink ,
From the surface side of the metal substrate, press-fitting a large number of rod-shaped protrusions made of a metal material having a higher thermal conductivity than the metal substrate in an arrangement relationship apart from each other,
Using at least the other end portion of the projection body coated with a coating metal;
As the coating metal, using a coating metal having a melting point lower than the melting point of each protrusion and the melting point of the metal substrate,
Press-fitting the other end of each projection into the surface of the metal substrate with one end of the projection protruding from the surface of the metal substrate;
Heating the coating metal of each of the protrusions press-fitted onto the surface of the metal substrate;
When the projections are press-fitted into the metal substrate, gaps generated around the projections on the surface side of the metal substrate are filled with the molten coating metal, and the molten coating is filled with the gaps. Solidifying the metal,
A method of manufacturing a heat sink. Assembling a plurality of rod-like protrusions constituting the heat sink into a plurality of sets, and initially pressing the protrusions constituting one set simultaneously into the metal substrate;
Next, simultaneously press-fitting a plurality of the protrusions constituting the group to be pressed next adjacent to the first press-fitted group to the metal substrate,
Repeating this in sequence, centering on the first press-fit group, adjacent to the previously press-fit group, and simultaneously pressing the plurality of protrusions constituting the next press-fit group into the metal substrate ,
The method of manufacturing a heat sink according to claim 5.

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