JP2002273530A - Punching machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a punching machine capable of suppressing the increase of clearance due to grounding of a mold and coping with various thick-plate materials by the same device. SOLUTION: In this punching machine, a punch 16 having a taper part 16b gradually tapered off toward its tip side and a stopper 17 having its tip 17a positioned on the same virtual plane with the tip surface 16a of the punch 16 are fitted to an upper die 1, and the punch hole 20 of a die 21 has a taper hole part 22 gradually tapered off toward an opening on the side of the punch 16. When an upper die 1 reaches a bottom dead point, the tip 17a of the stopper 17 is abutted on the die 21 and the surface 16a of the punch 16 and the upper surface 21a of the die 21 are made nearly flush with each other to punch a material 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a punching apparatus for punching a workpiece such as a metal plate.

[0002]

2. Description of the Related Art Conventionally, when punching a workpiece such as a flat metal plate, a processing die set in a press machine has been used. This processing die is composed of an upper die and a lower die, and the punch provided on the upper die is raised and lowered with respect to the material to be processed conveyed or placed on the lower die so that the punch and the die are removed. Punching is performed by the shearing action of

FIG. 6 is a sectional view showing the structure of a main part of a press die for punching a workpiece. In FIG. 6, reference numeral 40 denotes a punch supported on the movable side of the press machine which can move up and down, and its effective blade portion 41 is formed with a uniform width in the vertical direction and the horizontal direction. A stripper plate 42 is provided near the punch 40, and holds the workpiece 3 together with a die 50 provided in a lower die. The die 50 has a hole 51 formed at a position corresponding to the punch 40. The punched hole 51 of the die 50 is formed in a similar shape slightly larger than the punch 40,
It is a substantially conical or pyramidal space that narrows toward the opening (upper side in the figure) on the punch 40 side and expands toward the opposite side (lower side in the figure). The inner wall surface 52 of the die 50 is formed so as to be inclined by an angle θ with respect to the vertical direction of the punch 40, and a sharp cutting edge is formed at the edge 54 of the opening of the punched hole 51. A predetermined clearance d1 formed between the edge 54 and the outer periphery of the punch 40 is formed in the opening of the hole 51.

When the punch 40 descends from the state shown in FIG.
The punching process is performed on the workpiece 3 by the shearing action between the punch 40 and the punched hole 51 of the die 50. The punched product produced by this processing falls from the punched hole 51.

[0005]

In the conventional punching apparatus, when the punching by the punch 40 is performed for tens of thousands to millions of shots, the leading edge of the punch 40 and the punched hole 51 are formed. The sharpness deteriorates due to the wear of the edge portion 54. As a result, the shearing accuracy when punching the workpiece 3 deteriorates. Therefore,
In order to restore the sharpness of the punch 40 and the die 50, a cutting operation is performed to grind each end face and remove a worn portion.

However, when the end face of the die 50 is ground,
Since the hole 51 is inclined at an angle θ, the opening diameter of the hole 51 gradually increases. On the other hand, since the tip of the effective blade portion 41 of the punch 40 is formed with a uniform width in the elevating and lowering directions and the horizontal direction, the outer dimensions do not change even if grinding is repeated. As a result, the clearance d1 between the punched hole 51 of the die 50 and the punch 40 which has become larger gradually increases. That is, the punched hole 51 having the inclined angle θ
When the end face of the die 50 having
The increase amount of the clearance d1 on one side is as follows: d1 = Xtanθ (1) Incidentally, when the inclination angle θ of the punched hole 51 is 1 degree and the cut width of the end face of the die 50 is 1.0 mm, the clearance d1 on one side is increased by about 17 μm.

When the clearance d1 increases, sagging and burrs occur on the punched product, as is generally known. For this reason, there arises a problem that the quality as a punched product is significantly reduced. Further, when the opening diameter of the hole 51 becomes large, the mold is no longer usable and must be discarded, and the mold has a limited life. Therefore, it must be replaced with a new mold,
As a result, there arises a problem that the cost of the punched product increases.

As described above, the clearance d1 between the punch 40 and the die 50 is an important factor for the dimensional accuracy and quality of the punched product. However, in order to recover the sharpness by grinding the end surface of the die 50. If you have done the blade work of
When the clearance d1 is largely changed and the grinding is performed so that the clearance d1 is not largely changed, a problem has arisen that the blade sharpening operation becomes insufficient, so that sufficient sharpness cannot be recovered. .

In view of the above situation, the present invention provides a high quality punched product which can maintain an appropriate clearance even when a die and a punch are ground and bladed, and which has less dripping and burrs for a long period of time. It is intended to provide a punching apparatus which can be obtained.

[0010]

According to a first aspect of the present invention, there is provided a punching apparatus comprising: a punch mounted on an upper die; and a die having a punched hole corresponding to the punch. A punching apparatus for performing a punching process on the material placed on the die by pressing the punch, wherein the upper die has a punch formed with a tapered portion that gradually tapers toward a tip end; A stopper is attached which is located on the substantially same imaginary plane as the tip end surface of the punch, the punched hole of the die has a tapered hole gradually tapering toward the opening on the punch side, and the upper die is lower. When reaching a dead point, the tip of the stopper is brought into contact with the die, and the material is punched by setting the tip surface of the punch and the upper surface of the die to be substantially flush with each other. To have.

According to the punching apparatus of the present invention, the distal end face of the punch and the distal end face of the stopper, each of which has a tapered portion gradually tapering toward the distal end side, are positioned on substantially the same virtual plane. When the punch and the die are ground with the wear of the punch and the die, when performing the cutting with the same amount of grinding allowance, the substantially same virtual plane is maintained by grinding each end surface of the punch and the stopper with the same amount of grinding allowance. Further, by setting the same amount of die grinding allowance, the initial clearance amount can be maintained. Further, an arbitrary clearance can be set by making the grinding allowance of the punch and the stopper different from the grinding allowance of the die.

In the punching apparatus according to the second aspect of the present invention, the inclination angle of the tapered portion of the punch and the inclination angle of the tapered hole of the die are the same with respect to the vertical direction of the upper die. It is characterized by being formed at an angle.

According to the second aspect of the present invention, the taper of the punch and the tapered hole of the die have the same inclination angle, so that the grinding allowance for the punch and the stopper and the grinding allowance for the die are the same. By setting the amount, the clearance can always be kept constant.

According to a third aspect of the present invention, in the punching apparatus according to the second aspect, an adjusting means is provided between the upper die and the stopper, the movable means being movable in the elevating direction. The feature is to adjust the clearance between the punch and the die.

According to the third aspect of the present invention, the adjusting means is provided between the upper die and the stopper, and the adjusting means can arbitrarily change the tip position of the stopper. The clearance can be arbitrarily adjusted by forming the tip of the stopper so as to be substantially on the same virtual plane.

[0016]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of a punching apparatus according to the present invention. FIG. 1 is a cross-sectional view showing the overall configuration of a punching apparatus according to an embodiment of the present invention. The punching apparatus illustrated in FIG. 1 is applied to a press that moves up and down. This processing device is provided with an upper die 1 and a lower die 2, and is a device for punching by holding a plate-shaped workpiece 3 between these upper and lower dies.

The lower die 2 includes a die 21 made of structural carbon steel or the like fixed to the upper surface of a die holder 26 of a press. At the center of the die 21, a hole 20 having an opening having the same shape as the shape of the punched product is formed at a position facing the punch 16 described later. This hole 20
Is provided with a tapered hole 22 gradually tapering toward the punch 16 side, that is, toward the upper opening in the figure. The inner wall surface 23 of the tapered hole portion 22 is inclined at an angle θ2 of, for example, 0.2 to 15 degrees with respect to the vertical direction of the upper die 1, and a sharp cutting edge 24 is formed at an edge of the opening. . The cutting blade 24 has an effective blade portion 25 of about 3 to 5 mm in the thickness direction of the die 21, and is configured to maintain sharpness even when the upper end surface of the die 21 is ground.

A plurality of guide pins 28 are provided upright at predetermined positions of the die holder 2 of the lower die 2. Since the guide pins 28 are installed so as to be inserted into the guide holes 18 provided in the upper die 1, when the upper die 1 is lowered, the upper die 1 and the lower die 2 are uniquely defined in the horizontal direction. Positioned.

On the other hand, the upper die 1 is vertically moved by a press machine such as a hydraulic cylinder device (not shown) or the like, and a punch holder 13, a punch plate 12, and a guide support means 1 are provided.
5, a stripper plate 11, a punch 16, and a stopper 17 are provided. The punch plate 12 is fixed to the lower surface side of the punch holder 13, and the punch 16 is fastened with the tightening bolt 1 so that the tip corresponds to the hole 20 of the die 21.
9 attached to the punch holder 13. The stopper 17 is attached to the lower surface side of the punch plate 12, and its front end surface 17 a is connected to the front end surface 1 of the punch 16.
6a is formed so as to be located on substantially the same virtual plane as 6a. The stripper plate 11 is held movably up and down by a telescopic guide support means 15 penetrating the plate holder 13 and the punch plate 12,
When the upper die 1 descends, the workpiece 3 is held together with the die 21.

At the tip (lower end in the figure) of the punch 16,
A tapered portion 16b that gradually tapers toward the distal end is formed. In the present embodiment, the inclination angle θ1 of the tapered portion 16b is set to the same angle as the inclination angle θ2 of the tapered hole portion 22 of the die 21 described above. The outer shape of the tip end face 16a of the punch 16 is slightly smaller than the shape of the opening of the die 21. The blade 16c formed at the tip end of the punch 16 and the cutting blade 2 formed at the opening of the die 21 are formed.
4, a clearance d1 having a constant width in the horizontal direction is provided. The clearance d1 is set to, for example, a value of about 5% with respect to the thickness t of the workpiece 3. In addition, an effective blade portion 16d is provided on a distal end surface 16a of the punch 16 in a predetermined area toward the upper side in the figure. Therefore, by gradually grinding the effective blade portion 16d, the tip end surface 16a becomes a similar shape and gradually increases.

The upper mold 1 and the lower mold 2 have a guide post (not shown) fixed to the lower mold 2 and a guide provided on the upper mold 1 such that the guide post is slidably fitted. It is guided by a bush (not shown) so as to be freely movable toward and away from each other.

An embodiment in which the blank 3 is punched by using such a punching apparatus will be described with reference to FIGS.

After the workpiece 3 is conveyed onto the die 21 constituting the lower die 2, the upper die 1 is lowered by a hydraulic cylinder device or the like (not shown), and the stripper plate 11 places the workpiece 3 on the surface of the die 21. Press and hold. At the initial stage of the lowering of the upper mold 1, the tip end surface 16a of the punch 16 has not yet contacted the workpiece 3, but as the upper mold 1 descends, the guide support means 15 contracts, and as shown in FIG. The tip end surface 16a of the punch 16 contacts the workpiece 3. At this time, the stopper 17 which descends simultaneously with the punch 16
Since the tip 17a is located on the same virtual plane as the tip face 16a of the punch 16, the tip 17a is not in contact with the upper surface 21a of the die 21.

When the punch 16 is further lowered, the blade 16c of the punch 16 and the cutting blade 24 of the die 21 are moved as shown in FIG.
As a result, the workpiece 3 starts to be sheared into the same shape as the hole 20 (tapered hole 22). Then, when the punch 16 descends to 80 to 90% of the thickness of the workpiece 3, a crack 3 a is generated from a corner formed by shearing, and a break occurs. The portion pressed by the punch 16 is pressed into the hole 20 of the die 21.

Further, when the punch 16 descends, the
As shown in (1), the tip 17a of the stopper 17 contacts the upper surface 21a of the die 21, and the upper die 1 reaches the bottom dead center. At this bottom dead center, the tip end surface 16a of the punch 16 and the upper surface 21a of the die 21 are substantially coplanar, and the workpiece 3 is punched into a predetermined shape. In the present invention, as described above, the tip 17a of the stopper 17 and the tip
Since the punch 16 is located at the bottom dead center, the tip surface 16 a does not enter the tapered hole portion 22 of the die 21 because the punch 16 is located at the substantially same virtual plane. Therefore, the punch 16 and the cutting edge 24 of the die 21
Does not interfere with each other, and a so-called galling phenomenon can be prevented.

When the above punching is repeated for several hundred thousand to several million shots, the wear of the blade 16c of the punch 16 and the cutting blade 24 of the die 21 progresses. Therefore, in order to restore sharpness, it is necessary to grind each of the front end surfaces 16a and 21a to perform cutting to remove worn portions. In this embodiment, when grinding the distal end surface 16a of the punch 16, the distal end surface 17a of the stopper 17 also grinds the same amount as the grinding allowance of the distal end surface 16a of the punch 16. In this grinding operation, the punch 16 and the stopper 17 may be removed from the upper die, and both may be ground simultaneously with the respective end faces set on the same surface, or both may be ground individually with the same grinding allowance. good. In any case, when the punch 16 and the stopper 17 are set on the upper die 1, each of the tip surfaces 16
a and 21a are located on the same virtual plane.

On the other hand, the upper surface 21a of the die 21 is
It is preferable to perform the same amount of grinding as the grinding allowance of the stopper 17. This is because when the inclination angle θ1 of the tapered portion 16b of the punch 16 and the inclination angle θ2 of the tapered hole portion 22 of the die 21 are formed at substantially the same angle as shown in FIGS. The clearance d1 does not change even if the 21a, the punch 16 and the stopper 17 are ground by the same amount.

For example, if the inclination angles θ1 and θ2 are both 1
5 minutes (0.25 degrees), punch 16, stopper 1
7 and each end face of the die 21 are ground by 2.0 mm, respectively.
The opening of the tapered hole portion 22 extends horizontally by about 8.7 μm over the entire circumference. However, since the tapered portion 16b of the punch 16 also expands in the horizontal direction by about 8.7 μm from the same equation, the clearance d1 between the punch 16 and the die 17 does not substantially change. Therefore, according to the present embodiment, the clearance does not change even if grinding for the purpose of blade cutting is performed, and the area of the effective blade portions 16b and 41 of the punch 16 and the die 17 is sufficiently used to reduce the life of the mold. High quality products can be stamped out. In addition, even if the grinding is repeated until the end of the mold life, it is necessary to set the dimensions of the punched product so as not to be out of the allowable range.

In the case of using the punching apparatus shown in the above embodiment to punch workpieces having different thicknesses, the clearance between the punch 16 and the die 17 can be adjusted as desired. It is possible to do.

That is, the clearance d1 between the punch 16 and the die 21 is generally 5 to 5 of the thickness t of the material to be processed.
It is set to about 10%. Therefore, when punching a material having a relatively large thickness, the clearance d1 is required.
Set large. In the present embodiment, the punch 1
6, since the tapered portion 16b and the tapered hole portion 20 of the die 21 are inclined at substantially the same angle, the clearance d1 must be increased if the grinding allowance of the die 21 is larger than the grinding allowance of the punch 16 and the stopper 17. can do. For this reason, even when a blank having a large thickness is punched by the punching apparatus of this embodiment, the die 2 is
By increasing the amount of grinding 1 and increasing the clearance d1, it is possible to perform an appropriate punching process with respect to the plate thickness.

Conversely, when punching a material having a relatively small thickness, the clearance d1 between the punch 16 and the die 21 is set small. In this case, the clearance d1 can be reduced by setting the grinding allowance of the punch 16 and the stopper 17 to be larger than that of the die 21. Thus, according to the present embodiment, the punch 16
In addition, by appropriately making the grinding allowance of the stopper 17 different from the grinding allowance of the die 21, it becomes possible to set a desired clearance d1 amount.

Further, even if the blanks are made of substantially the same material, when the clearance d1 is made as small as possible, such as fine blanking or shaving, and the cut surface is finished beautifully and with high precision, the punch 16 and the stopper are used. 1
By making the grinding amount of the die 7 larger than the grinding amount of the die 21, it is possible to cope with the problem.

As described above, according to the present embodiment, the clearance d1 between the punch 16 and the die 21 can be arbitrarily adjusted. can do.

FIG. 5 is a sectional view of an essential part showing an embodiment in which adjustment means of the punching apparatus according to the present invention is added.
In FIG. 5, between the punch holder 12 and the stopper 17 constituting the upper die, a plurality of steel plates 37 formed to a predetermined thickness as clamping means are clamped and fixed by tightening bolts 19. These steel plates 37 can be removed one by one, and by changing the number of sandwiched steel plates 37, the tip surface position can be adjusted arbitrarily in the vertical direction without grinding the tip 17a of the stopper 17 without grinding. be able to.

Therefore, if the distal end face 16a of the punch 16 is ground by an amount corresponding to the thickness of the removed steel plate 37, the distal end face 16a of the punch 16 and the distal end 17a of the stopper 17 are maintained on the same virtual plane. be able to.

For example, the thickness of the steel plate 37 is set to 1.
When the thickness is set to 0 mm, the tip surface 16a of the punch 16 is ground by 1.0 mm every time one steel plate 37 is removed, and the blade is cut. When the number of punching is several hundred thousand to several million shots, the thickness of the steel plate 37 may be reduced. Therefore, after confirming the thickness of the steel plate 37 actually removed, the tip surface 16a of the punch 16 is removed. Grinding is preferred. Further, the area of the effective blade portion 16d formed on the tip side of the punch 16 is preferably set to be equal to or larger than the adjustable dimension of the adjusting means (steel plate 37).

FIG. 5 shows the adjusting means constituted by a plurality of steel plates 37. Instead of interposing the steel plates 37, the screwing dimensions of the tightening bolts 19 are adjusted so that the tip 17a of the stopper 17 can be adjusted. You may comprise so that height may be adjusted.

It is needless to say that the present invention is not limited to the embodiments described above, but can be variously modified without departing from the present invention. For example, the punch 16 and the tapered hole portion 22 of the die 21 in the present invention.
May have any shape such as a square or a circle. The punched product created by the punching apparatus according to the present invention is used in various fields such as electronic components, optical components, and medical components.

[0039]

As described above, according to the punching apparatus of the present invention, the punch having the tapered portion gradually tapering toward the distal end and the taper gradually tapering toward the opening on the punch side are provided. Since punching processing is performed on the material to be processed by the punched hole of the die with holes,
When the punch and die wear progresses, the change in clearance is minimized by making the amount of grinding for the punch and stopper equal to the amount of grinding for the die, so that high quality punched products with less dripping and burrs can be obtained. Can be processed for a long time. In addition, since the leading end surface of the punch and the leading end surface of the stopper are located on substantially the same virtual plane, the tip end surfaces of the punch and the stopper are also simultaneously used when performing blade cutting when the punch or die is worn. Grinding can be performed with a sufficient amount of grinding allowance, and the cutting operation can be further facilitated.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a punching apparatus according to the present invention.

FIG. 2 is a partial cross-sectional view showing a process of punching a workpiece by the punching apparatus according to the present invention.

FIG. 3 is a partial cross-sectional view showing a process of punching a workpiece by the punching apparatus according to the present invention.

FIG. 4 is a partial cross-sectional view showing a process of punching a workpiece by the punching apparatus according to the present invention.

FIG. 5 is a partial sectional view showing another embodiment of the punching apparatus according to the present invention.

FIG. 6 is a partial sectional view showing a conventional punching apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper die 2 Lower die 3 Workpiece material 11 Stripper plate 16 Punch 16a Punch tip surface 16b Tapered portion 17 Stopper 17a Stopper tip 20 Drilled hole 21 Die 21a Die upper surface 22 Tapered hole 37 Adjusting means

Claims (3)

[Claims] 1. A punching apparatus comprising: a punch attached to an upper die; and a die having a punched hole corresponding to the punch, wherein a punching process is performed on a material placed on the die by pressing the punch. In the upper die, a punch having a tapered portion gradually tapering toward the front end side and a stopper having a front end located on substantially the same virtual plane as the front end surface of the punch are attached, and the die is pulled out. The hole has a tapered hole gradually tapering toward the opening on the punch side, and when the upper die reaches the bottom dead center, the tip of the stopper is brought into contact with the die, and the tip face of the punch is A punching apparatus, wherein the material is punched with the upper surface of the die substantially coplanar. 2. The inclination angle of the tapered portion of the punch,
2. The punching apparatus according to claim 1, wherein an inclination angle of the tapered hole portion of the die hole is formed at the same angle with respect to a vertical direction of the upper die. 3. The clearance according to claim 2, wherein an adjusting means movable between the upper die and the stopper in the elevating direction is provided, and the clearance between the punch and the die hole is adjusted by the tip position of the stopper. Punching equipment.