JPH11245198A - Blanking punch and plate-like material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately perform outer shape punching without any burrs, slit punching and boring by a blanking punch press suitable for mass production while suppressing cracks on a printed circuit board or the like. SOLUTION: A plate-like material 2 is placed in a lower metallic die 1, a product presser 3 is moved in the lower metallic die 1 direction to grip and fixed the plate-like material 2 in the lower metallic die 1, an upper metallic die having a blanking punch 10 is moved in the direction of the lower metallic die 1, the blanking punch 10 being used for press machining to punch the outer shape of the plate-like material 2, or punch a slit or bore a hole. For this punch 10, the shape of the tip 11 part of punched surface longitudinal direction perpendicular section is formed to be recessed, and the punched direction section of both ends of the punched surface longitudinal direction are formed to be recessed. Also, division is made by a plane 15 passing nearly through the center of the recessed shape. Further, both ends of a slit hole for separation are formed to be recessed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a punching punch and a plate-like material provided with a slit hole in a case where a sheet-like material such as a printed circuit board or a composite substrate is punched by a press for punching an outer shape, slitting, and drilling.

[0002]

2. Description of the Related Art Conventionally, when punching, slitting, and drilling a printed circuit board, a drilling process, an end milling process, and a punching press process using a die have been performed. However, in the case of drilling and end milling, in the case of a fine pattern, the hole is small and the drill is easy to be broken, and the width of the slit etc. is too narrow to feed quickly, so the cutting time is long and the productivity is poor, so it is not suitable for mass production There was a problem.

[0003] On the other hand, in punching press working using a mold,
When there is a solder resist for preventing the reflow solder from adhering to the surface of the printed circuit board, the resist is cracked. Also, there is a problem that sagging occurs on the upper surface of the printed circuit board punch and burrs occur on the lower surface, and the cut surface shape is not straight. Therefore, as shown in FIG. 7, the both ends 25 of the slit hole 24 are processed by a drill before the press working, and the rectangular square punch 2 shown by a two-dot chain line after the hole working.
The punching is performed at 6.

[0004]

However, in such a case, there are two processing steps, and a shift in the processing position becomes a problem.
And the straight line portion 28 in the punch longitudinal direction shown by a two-dot chain line does not coincide with each other, so that there is a problem that a step 29 is formed in the product.
In addition, equipment with two steps of drilling and punching,
There was a problem that it took a lot of time.

[0005] Further, if the plate-like material to be processed has a square tip or the like such as a slit, cracks are likely to occur at corners during processing, transportation and storage. Therefore, as shown in FIG. 8, both end portions 25 of the slit holes 24 of the plate-like material 21 such as a composite substrate are formed into semicircular long holes, and as a result, processing is troublesome as described above, and There is a problem that it is difficult to separate the products 22 separated by the slit holes 24.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, it is an object of the present invention to press out a plate-shaped material such as a printed circuit board and the like by a press working suitable for mass production while suppressing cracks. It is an object of the present invention to provide a punch that can be slit and pierced, and to provide a plate-like material that is not easily cracked and is easily separated.

[0007]

In the present invention, a plate material is placed on a lower mold, and a product holder is moved in the direction of the lower mold to pinch and fix the plate material to the lower mold. In the punching punch used for press working in which the upper die provided with is moved in the direction of the lower die to perform the outer punching of the plate-shaped material, or the punching or slitting, the punching surface at the tip of the punching punch. The above object has been attained by forming the cross section perpendicular to the longitudinal direction into a concave shape and forming the cross sections in the punching direction at both ends in the longitudinal direction of the punching surface into a concave shape.

By making the cross section perpendicular to the longitudinal direction of the punching face at the tip of the punch into a concave shape, the tool tip can be made a sharp edge, so that the contact surface between the solder resist on the substrate surface and the tool tip is reduced to concentrate the stress. An initial crack is generated at the tip of the tool to release the stress on the surface of the printed circuit board, and it is possible to prevent cracks from occurring and developing in other parts. However, if both ends in the longitudinal direction of the punching surface are semicircular, a sharp edge cannot be formed in the semicircular portion only by making the tip shape of a cross section perpendicular to the longitudinal direction of the punching surface concave. Also, when punching, the straight part in the longitudinal direction and the semicircular parts at both ends do not contact the product at the same time. Drops and cracks occur. Therefore, in the present invention, furthermore, the punching direction cross section of both ends in the punching surface longitudinal direction is concave, eliminating the time difference when the punch hits the product, preventing the pulling force from being generated on the product, This enables punching without cracks.

If the tensile stress on the substrate surface generated at the time of punching is relaxed, sagging and cracks can be further prevented. Also, to make concave processing easier,
In claim 2, each of the concave shapes is divided by a plane passing substantially through the center.

[0010] By dividing the punch into two,
A punch having a concave cross-section can be easily obtained by setting two punches having inclined front end surfaces with their slopes facing each other. Also, when the tip of the punching tool is processed into a sharp edge, it can be processed linearly by a plane polishing machine or the like, so that the processing is easy. In addition, when the tip of the punch bites, it can be slightly deformed outward,
The tensile stress on the substrate surface can be reduced.

Such a punch is suitable for punching a plate-like material having a large aspect ratio of a punched surface, and the punch is preferably used for slitting a vertically long punched surface.

The plate-like material slit by the punching punch has high accuracy without cracks in the product, and has a concave shape at both ends, so that it can be easily separated. In addition, the plate-like material in which both ends of the slit hole are concave in shape is novel and has a feature that it is easy to separate (claim 5). Further, such a plate-like material is suitable for a printed circuit board (claim 6).

[0013]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view of a press, a press die, a punch (hereinafter referred to as a punch) and the like showing an embodiment of the present invention as viewed in a cross section perpendicular to the longitudinal direction of a punch punch plane, and FIG. 2 is along a punch punch plane. FIG. 3A is a front view of the punch, FIG. 3B is a side view, and FIG. 3C is a bottom view of the tip viewed from the punching surface side. In FIG. 1, a printed board 2 which is a composite board is placed on a lower mold 1. The printed circuit board 2 has a glass fiber layer 2 sandwiching a central epoxy layer 2a.
b, 2c, epoxy layers 2d, 2e, resist layers 2f, 2
The layers are stacked in the order of g. As the upper mold (not shown) descends, a holding plate 3 for holding and fixing the printed circuit board 2 on the lower mold is provided.

A punch 10 is provided in an upper mold (not shown). The punch descends as the upper mold descends, penetrates into the printed circuit board 2, and cuts an outer shape, a slit, or a hole in the printed circuit board. It is made possible by pressing. The punch can be moved in and out of the press plate 3 and the lower die (die) 1 at a position corresponding to the punch 10 with a minute gap.

As shown in FIGS. 1 and 3 (b), the punch 10 is divided into two along a longitudinal center plane 15, and the tip 11 has a punching surface having a cross section perpendicular to the longitudinal direction. It is inclined from both ends 11 toward the center 13,
It has a concave shape as a whole, and both ends 11 are sharpened. Further, the punch 10 is shown in FIGS.
As shown in (c), both end portions 12 in the longitudinal direction of the punching surface are similarly curved and inclined in a concave shape from the corner portion 12a toward the center 14, and have a concave cross section in the punching direction. The corner 12a is rounded. An upper portion 16 is a flange for attaching and fixing the punch to the upper mold.

According to this configuration, the tip 11 of the punch comes into contact with the surface 2h of the printed circuit board 2 to generate a crack for cutting the printed board at the tip, and the tip of the punch advances inside the printed circuit board. At the same time both ends 12
Corner 12a also contacts the printed circuit board surface 2h, causing a crack in the printed circuit board 2 for cutting, and the corner advances into the printed circuit board. At this time, since the inclined surface 11b and the curved inclined surface 12b are formed from the tip 11 toward the center 13 and from the corner 12a toward the center 14, respectively, no tensile stress is generated on the printed circuit board 2, and A sharp cut surface without cracks is obtained.

[0017]

EXAMPLE A punch hole was punched out of a printed circuit board using such a punch. The specifications of the punch were a slit hole width of 1.5 mm, a slit hole length of 28 mm, a concave radius of about 0.55 mm at both ends, a round chamfer radius of the corner 12 of about 0.1 mm, and an angle α of the inclined surface 11 b of about 0.5 mm. 45 °. The printed board 2 having a thickness of 0.4 mm is formed by the punch.
After punching a slit hole in
There were no cracks.

On the other hand, FIG. 5 shows a comparative example punch used for comparison with the present invention, wherein (a) is a front view, (b) is a side view,
(C) is a bottom view showing the tip as viewed from the punching surface side, and FIG.
FIG. 4 is an explanatory view of a slit punched by a comparative example punch. As shown in FIG. 5, the tip shape of the punch 30 at the cross section perpendicular to the punching surface longitudinal direction is inclined from both the tips 31 toward the center 33, is concave as a whole, and the tips 31 are sharpened. I have. However, both end portions 32 in the longitudinal direction of the punching surface have a semicircular shape convex outward.

Therefore, in the comparative example, tensile stress is hardly generated on the printed circuit board 2 in the longitudinal direction, but tensile stress is generated on the printed circuit board at the both ends 32 at the time of punching. When the same punching operation as described above was performed using the punch of the comparative example, cracks 36 were generated outside the semicircular ends 35 of the slit hole 34 as shown in FIG. From this, the effectiveness of the present invention was confirmed.

In the present invention, the distal end and the longitudinal ends are formed into a concave shape to prevent the generation of a pulling force at the distal end. In the above-described example, the inclined surface from the distal end 11 toward the center 13 is formed. 11b is a straight line (concave V shape), but if it is concave, it may be a curve (concave R, concave semicircular shape), and the shape is not limited. Also, punch tip 1
1 has a large cutting length, so it is better to be sharp.

On the other hand, both corners 12a are located at the center 1 from the corner.
The curved (concave semicircular) inclined surface 12b toward 4 is used,
It may be a straight line. In addition, the rounding is chamfered because the influence on the cutting is small. However, the curved inclined surface 12b and the corner 1
When 2a is made straight and sharp, punch processing is easy, but sharp corners are formed at both ends of the slit hole on the printed circuit board side to be punched out, and cracks and cracks occur during transport after punching processing and other processing. Since it is likely to be a source of generation, it is better to perform rounding or chamfering even if it is minute, rather than leaving it sharp. Further, by dividing the punch 10 into two parts, processing can be facilitated, an outward spread can be generated, and generation of a pulling force can be further prevented. It goes without saying that they may be integrated without being combined.

FIG. 4 is an explanatory view showing an example of a printed circuit board in which slits for obtaining a plurality of products are processed in the same manner as in FIG. 8 using the punches shown in FIGS. It is. A plurality of square pieces 20 are punched in the printed circuit board 2 around the periphery of a plurality of square pieces 20. As described above, the slit hole 4 is accurately punched without anybody or crack. Both ends 5 of the slit hole 4 are curved inclined surfaces from the corners 5b, 5a toward the center 5c, and the inner corners 20a of the square piece 20 are formed.
The inner corner portion 5a is located at the center.

Therefore, the square piece 20 can be easily separated from the inside corner 5a as a starting point, and a product such as a square piece from a sheet such as the printed circuit board 2 or a product can be easily separated from a product. In addition, since cutting can be performed from the product side, unnecessary protrusions of the product can be minimized. Such a printed circuit board can be easily punched by a punching press using the punch of the present invention,
It is not surprising that the same advantages can be obtained by performing an end mill or other cutting.

[0024]

According to the present invention, the punching press is formed by forming the tip shape of the cross section perpendicular to the longitudinal direction of the punching surface of the punching punch into a concave shape and the cross section in the punching direction at both ends in the longitudinal direction of the punching surface into a concave shape. ,
Since high-precision punching without burrs and cracks can be performed, it is also possible to punch a printed circuit board having a surface coated with a thermosetting solder resist or the like. Further, it is suitable for punching a plate-like material such as a printed board, particularly for punching an outer shape or slit. Furthermore, since a plate-shaped material such as a printed circuit board is punched out while suppressing cracks with a low-cost mold, the processing time is short, the manufacturing cost is greatly reduced, and the device is more suitable for mass production.

Further, when the punch member is divided, a concave shape at the tip or both ends can be easily formed, the punch accuracy is good, and the cost of the punch can be kept low.

Further, the plate-like material such as a slit-shaped printed circuit board punched by the punching punch of the present invention has a concave shape at both ends of the slit and separates a plurality of products provided on one plate. Easy to do, less unnecessary parts,
Post-processing is also easy.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a press, a press die, a punch, and the like showing an embodiment of the present invention as viewed in a cross section perpendicular to a punching plane longitudinal direction.

FIG. 2 is a cross-sectional view (a cross-sectional view taken along line AA in FIG. 1) of a punching punch according to the embodiment of the present invention, taken along a punching plane.

3 (a) is a front view of a punching punch, FIG. 3 (b) is a side view, and FIG. 3 (c) is a bottom view of the tip viewed from the punching surface side, showing an embodiment of the present invention.

FIG. 4 is an explanatory view showing an example of a printed circuit board having slit holes according to the present invention.

5A is a front view, FIG. 5B is a side view, and FIG. 5C is a bottom view showing a tip viewed from a punching surface side of a comparative punching punch used for comparison with the present invention.

FIG. 6 is an explanatory view of a slit punched by a punch punch of a comparative example used for comparison with the present invention.

FIG. 7 is an explanatory diagram of conventional slit hole processing.

FIG. 8 is an explanatory view showing an example of a conventional printed circuit board in which slit holes are processed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lower die 2 Plate material, printed circuit board 3 Product holding 4 Slit hole 5 Both ends of slit hole 10 Punching punch 11 Tip of cross section perpendicular to the longitudinal direction of punching surface 12 Both ends in longitudinal direction of punching surface 13, 14 Almost concave Center 15 division plane (plane passing through the center of concave shape)

Claims (6)

[Claims] 1. An upper die provided with a punch, wherein a plate-shaped material is placed on a lower die, and a product press is moved in the direction of the lower die to clamp and fix the plate-shaped material to the lower die. In the direction of the lower mold, punching the outer shape of the plate-shaped material, or punching used in the press working which is made to perform slit punching or drilling, etc., in the punching surface longitudinal direction perpendicular to the tip of the punching punch A punch having a concave cross section and a concave cross section in the punching direction at both ends in the longitudinal direction of the punching surface. 2. The punch according to claim 1, wherein the punch is divided by a plane passing substantially through the center of each of the concave shapes. 3. The punch according to claim 1, wherein said punch is a punch for punching a slit having a vertically long punching surface. 4. A plate-shaped material which has been subjected to slit punching by the punch according to claim 3. 5. A plate-shaped material characterized in that both ends of a slit hole for separating the material are concave. 6. The plate material according to claim 4, wherein the plate material is a printed circuit board.