JP4710054B2 - Manufacturing method and manufacturing apparatus for heat sink for electronic device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method and apparatus for manufacturing a heat sink for electronic equipment, and in particular, manufacturing a heat sink made of Cu and a Cu-based alloy of a power semiconductor module or an IC package by a progressive die having a plurality of stages. It relates to a method and a device.
[0002]
[Prior art]
A power semiconductor module is a semiconductor device composed of a semiconductor element, a copper pattern, an insulating substrate, a conductor layer, and a heat sink, and is widely used in home appliances such as air conditioners and washing machines, automobiles, and industrial equipment. Because it is necessary to efficiently dissipate the heat generated from these power semiconductor modules, a heat sink that is excellent in thermal conductivity and inexpensive in terms of cost is required, and Cu and Cu-based alloys are widely used. Yes. When the heat sink of the power semiconductor module is soldered to the board, when the solder is solidified, the heat sink warps due to the difference in thermal expansion coefficient between the insulating board and the heat sink. Will gradually restore. The amount of warping during solder solidification corresponds to 0.2% proof stress, heat resistance, board size, and heating conditions of the material used for the heat sink. The heat radiating plate is further attached to a cooling fin or the like via heat radiating grease. At this time, a large contact area with the cooling fin is important in order not to disturb the heat radiation performance. Therefore, in order to obtain flatness after soldering and joining the substrates, a predetermined amount of warpage that can cancel out the warpage is taken into consideration in advance.
[0003]
In the process of manufacturing heat sinks with a thickness of 0.5 to 6 mm, which are often used for power semiconductor modules, generally, a punching machine is used to punch a product from a plate material once with a single press. The necessary warpage is given to the product. When a product is pressed from a plate material, the plate material is sheared in advance to a size that is easy to handle. At this time, the product shape after pressing is likely to be affected by the strain and internal stress applied to the material. In some cases, it is necessary to pass a leveler before pressing.
[0004]
[Problems to be solved by the invention]
As described above, since many processes are involved and the quality is difficult to stabilize, there has been a serious problem in terms of productivity and cost. Specific issues are as follows.
[0005]
1) When the material to be processed is transferred in the progressive die due to its own weight, the product is scratched with the die.
[0006]
2) The pressing device / process is different from the warping device / process, which causes an increase in manufacturing cost.
[0007]
3) Since the pressed work material is cut off from the plate material, even if a warping die is incorporated in the die, its conveyance and positioning are difficult, and a predetermined amount of warping cannot be applied to the work material.
[0008]
4) The sheared plate is greatly affected by distortion and internal stress and cannot be warped stably.
[0009]
5) When a warping device is incorporated in a mold, it is difficult to cope with the adjustment of the warping amount that varies depending on the workpiece (product).
[0010]
[Means for Solving the Problems]
The manufacturing method of the heat sink for electronic devices of this invention is the order which carries out a predetermined | prescribed process by sequentially transferring the workpiece for a heat sink of thickness 0.5-6mm in the progressive metal mold | die provided with the several stage. The plurality of stages include a stage for side-cutting the width direction of the workpiece material into a product dimension before warping, a product separation stage, and a warping stage, and the workpiece materials are sequentially processed. When feeding, the product after the work material is lifted from the lower mold by the guide for supporting the work material provided in the mold and separated from the work material in the product separation stage, the warping stage When the product is fed onto the warp mold part, the product is pushed forward to the warp stage by the subsequent work material, and a predetermined position is provided by a product stopper structured to brake from the side of the product. In is stopped, characterized by imparting a warp required to the product in the mold.
[0011]
The support guide is in contact with only an edge portion of the work material.
[0015]
An apparatus for manufacturing a heat radiating plate for electronic equipment according to the present invention comprises a progressive die having a plurality of stages, and a work material for a heat radiating plate having a thickness of 0.5 to 6 mm before the plurality of stages are warped. It has a stage that side-cuts the width direction to the product dimensions, a product separation stage, and a warping stage. In this progressive mold, the work material to be sequentially transferred is floated from the lower mold in the progressive mold. A guide for supporting the product, means for separating the product from the material to be processed in the product separation stage of the progressive die, and a warp die portion for imparting a warp necessary for the product in the progressive die, And means for stopping the product at a predetermined position of a structure for applying a brake from the side of the product when the product is fed onto the warping mold part by the subsequent work material. .
[0016]
The warpage die portion for imparting the necessary warpage to the product within the die is characterized in that it can be replaced independently without removing the entire progressive die from the press.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0018]
In the figure, 1 is a pilot piercing and product piercing stage, 2 is an idle stage, 3 is a side cut stage, 4 is an idle stage, 5 is an engraving stage, 6 is a product separation stage, 7 is a warping stage, 8 Is a stripper plate, 10 is a punch for piercing, 11 is a punch for side cut, 12 is a warping piece, 13 is a lower warping piece, 14 is a pressing pressure adjusting bolt, 15 is a product stopper, and 16 is a product. , 17 is a product guide, 18 is a mold, 18a is a lower mold, 18b is an upper mold, and 19 is a material.
[0019]
FIG. 8 shows a configuration example of a heat sink production line using a progressive die according to the present invention. The material 19 supplied by the hoop is wound, and the warpage differs in the longitudinal direction due to the difference in the radius between the inside and outside of the hoop. Even if this is pressed and warped as it is, a stable product warp cannot be obtained. In order to obtain a stable product warp, it is desirable that the warp of the material before pressing is flat.
[0020]
The present invention uses a hoop material that is less affected by strain and internal stress than a sheared plate in the manufacture of a heat sink with a thickness of 0.5 to 6 mm that is often used for power modules made of Cu and Cu-based alloys. In addition to progressive processing, the process of warping in the progressive mold is simultaneously performed to improve productivity and stabilize quality. As shown in FIG. 8, the work material (hoop material) 19 is sent to the progressive die 22 in a state of being wound up through the leveler 20 and the progressive device 21.
[0021]
A guide 8 capable of supporting the work material 19 from the lower mold 18a by supporting the flaws that are likely to occur due to the weight of the work material 19 when the feed material 22 is fed forward. It can be suppressed by providing. 2A and 2B show the operation of the guide 8. The guide 8 is normally in the raised position as shown in FIG. 4 by a spring (not shown) incorporated in the lower mold 18a , and is pushed by the stripper plate 9 and lowered together with the material 19 during pressing. At this time, as shown in FIG. 2A, the stripper plate 9 is grooved so that the guide 8 stops at a position where it does not interfere with the material 19 and the lower mold 18a. 2B, as the stripper plate 9 is raised, the guide 8 is also raised together with the material 19, and the lower mold 18a and the material 19 are fed in a non-contact state.
[0022]
In the present invention, the material 19 transported into the mold 18 in FIGS. 1A, 1B and 7 is a stage 1, and the pilot pierce 10a and the product pierce 10b are punched by the punch 10 and a similar punch (not shown). Set up. The pilot earrings are two holes provided in the vicinity of the center of the material for positioning the material and transferring the inside of the progressive die at an equal pitch. This part is cut in the stage 6 and does not become a product. The product piercing is a hole at both ends necessary for screwing the power semiconductor module as a product. Stage 2 is an idle stage.
[0023]
Next, the width direction of the material is side-cut to the product dimension by the punch 11 on the stage 3. Stage 4 is an idle stage.
[0024]
Next, an inscription for product identification is given at stage 5. This is not always necessary depending on the product specifications. Only the stamped part can be replaced, and it can be used for various specifications.
[0025]
That is, when the material 19 is sequentially fed through these stages, the side portions are held by the guide 8, and the surface of the material is neither on the mold 18 nor on the guide 8 as shown in FIGS. 2A, 2B, 3A and 3B. Sent without contact. As shown in FIG. 4, the guide 8 is set so that the material 19 is lifted by about 1 mm from the lower mold 18a by a spring installed in the mold 18. However, this is not a fixed value, and when adjustment is necessary due to the difference in the supply state of the material 19, the guide 8 is divided into two parts, upper and lower, and is connected by bolts. is there. In the unlikely event that a progressive trouble occurs, the material 19 can be released from the guide 8 by removing this bolt, and the return can be facilitated. The contact portion between the guide 8 and the work material 19 is tapered as shown in FIGS. 3A and 3B, and each corner portion is rounded so that it does not contact the surface of the work material. As a result, the work material 19 does not come into contact with the mold when it is fed forward, and the guide 8 itself does not come into contact with the work material surface, so that surface defects such as scratches on the product 16 can be greatly reduced. It becomes.
[0026]
Next, the product 16 is separated from the material 19 to a predetermined size on the stage 6. Here, the pilot pierce portion for material transfer is cut off.
[0027]
The product 16 separated from the material 19 at the stage 6 is pushed to the warping mold of the stage 7 by the subsequent material 19 and is pressed from above and below by the upper warping piece 12 and the lower warping piece 13 to give a predetermined warpage. In this case, the center of the warping pieces 12 and 13 and the product 16 is important. In order to perform stable warping within the progressive die, it is necessary to perform warping after the material 19 has been punched into the shape of the heat sink with a press. If the material 19 is warped, a part of the flat material will be deformed, making it impossible to smoothly feed in the mold, or releasing the stress of the material when it is punched into the product, resulting in a stable warp. Such as inability to obtain Therefore, to produce a stable warped product, it is desirable to perform warping after separating the product from the material. However, since the product 16 is separated from the material in the stage 6 shown in FIGS. 1A and 1B, the product 16 is pushed by the subsequent material after the stage 7, and proceeds in the progressive die 18. Since it is separated from the material and is in a free state, the stop position on the warping die of the next stage 7 is not constant. If warping is performed in a state where the warping pieces 12 and 13 are deviated from the predetermined positions in this way, the amount of warping applied is not stable and the product performance is also hindered. Therefore, the product stopper 15 shown in FIG. 6 can be adjusted so that the product 16 stops at a predetermined position on the warping die. The product stopper 15 has a structure in which a brake is applied from the side of the product 16, and adjustment is performed by changing the spring pressure with the bolt 14. As a result, the amount of warpage of the product 16 is stabilized, and the defect rate can be greatly reduced.
[0028]
The distance between the product stopper 15 and the product guide 17 shown in FIG. 6 is adjusted for each warpage die depending on the size of the product 16 or the like. The pressing pressure of the product stopper 15 is adjusted by changing the spring pressure by the pressing pressure adjusting bolt 14 and is adjusted so that the product 16 stops at a fixed position.
[0029]
Although the warping pieces 12 and 13 and the product stopper 15 are incorporated in the warping die, they are structured to be removable as a unit as shown in FIGS. 5A and 5B. Not only when switching to products with the same dimensions but different warpage amount, even if the specified warpage amount cannot be obtained due to the difference in the material supply state, it can be easily replaced with several types of warp amount pieces prepared in advance. The setup change time can be shortened.
[0030]
In the present invention, the product can be warped in a progressive die. When the power semiconductor module heatsink is soldered to the board, when the solder solidifies, warpage occurs due to the difference in thermal expansion coefficient between the insulating board and heatsink, and then gradually recovers due to solder creep over time. However, in order to obtain flatness after joining, it is necessary to add a warp that can offset this in consideration of the amount of warp restoration. 5A and 5B show the appearance of the warp die. The mold has a set of hemispherical convex and concave warping pieces, and the size and shape of the pieces vary depending on the size, material, warpage specifications, etc. of the heat sink to be manufactured. It is necessary to prepare a tag. Although these are bolted as shown in the figure and incorporated in the progressive die, the entire progressive die is removed from the press machine, and only the warped die portion can be replaced as needed. For example, when switching to a product with the same warpage and a different amount of warpage, or when a predetermined amount of warpage cannot be obtained due to the difference in the supply state of the material, it is easy to change the setup. The replacement time can be shortened.
[0031]
【The invention's effect】
As described above, according to the present invention, it is possible to simultaneously perform stamping and warping with a press, which has been conventionally performed in a separate process in manufacturing a heat sink, by progressive feeding. In addition, along with the progressive feeding, the occurrence of defects is reduced by preventing scratches by the movable guide and improving the positioning accuracy on the warped die part, etc., which enables mass production at low cost by progressive feeding. Combined with the reduction in the number of non-defective products, there is a significant benefit that can significantly reduce product costs.
[Brief description of the drawings]
FIG. 1A is a plan view showing a layout of a progressive die according to the present invention.
FIG. 1B is a front view showing a layout of a progressive die according to the present invention.
FIG. 2A is an operation explanatory diagram of a product guide.
FIG. 2B is an operation explanatory diagram of a product guide.
FIG. 3A is a front view of a product guide.
FIG. 3B is a side view of the product guide.
FIG. 4 is a structural diagram of a product guide.
FIG. 5A is a front view for explaining attachment of a warping die.
FIG. 5B is a side view for explaining attachment of a warp die.
FIG. 6 is a front view of a product stopper.
FIG. 7 is an explanatory diagram of the progressive die shown in FIG. 1A.
FIG. 8 is an explanatory diagram of a production line for a heat sink according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Pilot piercing and product piercing stage 2 Idle stage 3 Side cut stage 4 Idle stage 5 Engraving stage 6 Product separation stage 7 Warping stage 8 Guide 9 Stripper plate 10 Piercing punch 10a Pilot piercing 10b Product piercing 11 Side Cutting punch 12 Upper warping piece 13 Lower warping piece 14 Pressing pressure adjusting bolt 15 Product stopper 16 Product 17 Product guide 18 Mold 18a Lower die 18b Upper die 19 Material 20 Leveler 21 Progressive device 22 Progressive die

Claims (9)

A progressive machining method in which a workpiece for a heat sink having a thickness of 0.5 to 6 mm is sequentially transferred into a progressive die having a plurality of stages to perform a predetermined process, wherein the plurality of stages are warped. Workpiece provided on the mold when the workpiece material is fed in order, having a stage that side-cuts the width direction of the workpiece material into the product dimensions before attaching, a product separation stage, and a warping stage When the product is lifted from the lower mold by the guide that supports the product and separated from the workpiece material in the product separation stage, the product is sent onto the warping mold part of the warping stage. The product is pushed to the warping stage by the subsequent work material, stopped in place by a product stopper structured to brake from the side of the product, and required for the product in the mold. Method of manufacturing an electronic device for radiating plate, which comprises applying an Ri. The plurality of stages have a drilling stage, and a pilot pierce is drilled in the drilling stage, and then the product is separated from the material to be processed in the product separation stage , where the pilot pierce part is cut off. The manufacturing method of the heat sink for electronic devices of Claim 1 characterized by the above-mentioned. 3. The method of manufacturing a heat sink for an electronic device according to claim 1, wherein the work piece for the heat sink is sent to the progressive die in a state of being wound through a leveler and a progressive device. . Wherein the support guide method according to claim 1, 2 or 3 electronics heat sink, wherein the contacting only an edge portion of the work piece. The manufacturing method of the heat sink for electronic devices of Claim 1, 2, 3 or 4 characterized by giving the curvature required for a product within the metal mold | die to the said workpiece material. A progressive die having a plurality of stages, a stage in which the plurality of stages are side-cut into a product dimension in the width direction of a work piece for a heat sink having a thickness of 0.5 to 6 mm before warping; A guide that has a separate stage and a warping stage, and in which the work material that is sequentially transferred is floated and supported from the lower mold in the progressive mold, and the product of the progressive mold Means for separating a product from the workpiece material in a separate stage; a warp die portion for imparting a warp necessary for the product in the progressive die; and the warping of the product by the workpiece material that follows. An apparatus for manufacturing a heat radiating plate for electronic equipment, comprising means for stopping the brake at a predetermined position of a structure in which a brake is applied from the side of the product when it is sent onto the mold part. The plurality of stages have a drilling stage for drilling pilot piercings in the work material, and the product is separated from the work material by the product separating stage, and has means for separating the pilot piercing part by pressing. The manufacturing apparatus of the heat sink for electronic devices of Claim 6 characterized by the above-mentioned. The electronic device heat radiation plate according to claim 6 , wherein the material to be processed is a hoop material, and includes a leveler and a sequential feeding device that take up the hoop material and feed it to the progressive die. Manufacturing equipment. 8. An electronic device according to claim 6 or 7, wherein a warp die portion for imparting a warp necessary for a product in the die can be replaced independently without removing the entire progressive die from the press. Equipment for manufacturing equipment heat sinks.

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