JPH091258A - Piercing method of soft material and soft laminated material with turret punch press machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To pierce not to generate permanent strain due to a blank holder by taking wide spacing at positioning a material to be worked between a lower die and upper die and narrow spacing at pulling out the upper die from the material to be worked. SOLUTION: A piston 12 is descended with a ram 13 by supplying hydraulic working oil to a chamber A of a cylinder 12a, a material W to be worked is pressed by descending an upper die assembly 36. At this time, an upper die holder 37 is descended by rotation-driving a servo motor 61 so that the upper die holder 37 does not cause permanent strain to the material W to be worked and holds its position. Thus, among parts constituting the upper die assembly 36, the part to affect the material W to be worked due to piercing is the minimum range of a cutting blade part of punch 31 only, as a result, there is no possibility of generating large permanent strain to the outer periphery of cutting blade. Further, when the upper die assembly 36 is pulled out, because ascending is regulated by the upper die holder 37, the material W is not lifted upward.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a turret for a soft material such as urethane rubber or a soft laminated material obtained by adhering a foamed resin material or the like to the metal material, in addition to a metal material such as iron, stainless steel or aluminum. The present invention relates to a method of punching with a punch press.

[0002]

2. Description of the Related Art Conventionally, as a material to be perforated by a turret punch press machine, a hard material such as iron, stainless steel, or aluminum is used. The work piece is pressed by a large force of ton, and when the upper die is lifted and separated from the work piece after processing, the work piece is prevented from rising together with the upper die.

Also, in the case of the turret punch press die, the larger the number of dies mounted on the turret, the less the labor of exchanging the dies and the better the working efficiency. Therefore, the stripper which is the plate pressing portion has a small diameter. Since the structure is adopted, the surface pressure of the stripper pressing the work material at the time of drilling the work material is also high.

Therefore, by utilizing the advantage of the turret punch press that it is possible to make holes by combining a plurality of kinds of dies with a shape of dozens of holes, a laminated material or the like to which a soft material or a foamed resin material is adhered, etc. When drilling is applied to
As shown in FIG. 9, the stripper 301, which is the plate pressing portion, is small, and the surface pressure when the stripper 301 presses the work piece is large, so that the dent Q is generated in the soft material and remains as a permanent set. In order to solve this problem, a special mold had to be prepared each time.

[0005]

SUMMARY OF THE INVENTION In view of the above-mentioned prior art, the present invention has an advantage of a turret punch press capable of punching holes even by dozens of hole shapes by a combination of machining by several kinds of dies. Using the turret punch press machine, a soft material and a soft laminated material that can be used to perforate a work material, which is a laminated material to which a soft material or a foamed resin material is adhered, without causing permanent strain by a stripper. It is an object of the present invention to provide a method for drilling a hole.

[0006]

The structure of the first invention of the punching method of the present invention made for the purpose of solving the above-mentioned problems is to position a plate-shaped workpiece on an X, Y plane.
A Y positioning device, an upper turret for mounting the upper mold, a lower turret for mounting the lower mold, and an upper mold holder arranged on the upper turret for accommodating and holding the upper mold so as to be slidable in the vertical direction.
And a turret punch press machine comprising an upper die and a lower die arranged on the upper and lower turrets, and a press drive device having a ram for pressing the upper die. Means for changing the vertical space from the upper surface of the lower mold to the lower surface of the upper turret or between the upper surface of the upper mold holder and the lower surface of the lower mold provided for positioning between the molds are provided. It is characterized in that the space is widened when positioning between the molds, and the space is narrowed when the upper mold is pulled out from the workpiece after punching.

Further, the structure of the second invention of the punching method of the present invention is such that the plate-shaped workpiece is positioned on the X, Y plane.
A positioning device, an upper turret for accommodating and holding one or a plurality of upper molds in a vertically slidable manner, a lower turret for mounting a lower mold paired with the upper turret, and at least a plate retainer arranged on the upper turret. Turret punch including one or a plurality of upper molds each having a cutting portion and a cutting edge portion, a lower mold arranged in a lower turret, and a press drive device having a ram for pressing the upper mold downward. In the press machine, a stopper device is provided that abuts so that the plate pressing part of the upper mold is received by the press machine main body side when the upper mold is lowered,
When the upper die is pressed downward by the press drive device and descends, the lower end of the cutting edge portion of the upper die descends to a position where it penetrates the workpiece, but the plate retainer of the upper die. Is characterized by contacting the main body of the press machine during the downward movement to prevent further downward movement, and performing the drilling with the lower end thereof in contact with the workpiece.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION In the method of the first invention of the present invention, when a turret punch press machine is used to punch a soft material or a laminated material obtained by adhering a soft material to a hard metal material, When positioning between the lower mold and the upper mold, widen the vertical space from the upper surface of the lower mold to the lower surface of the upper mold base or from the upper mold holder to the lower surface for the workpiece to pass. To facilitate the passage of the work material, and when drawing the upper mold from the work material after drilling, narrow the space so that it can be pulled out, and lift the work material when drawing the upper mold. In addition to preventing it, the force to lift it is received by the upper mold holder with a larger area than the upper mold and the lid provided on the bottom of the upper turret,
By reducing the surface pressure applied to the work material, it became possible to realize drilling without permanent distortion.

The method of the second invention in the present invention is
When punching a soft material or a laminated material in which a soft material is adhered to a hard metal material, the plate retainer (hereinafter referred to as the stripper) descends so that the plate retainer does not strongly press the workpiece. Stopper forcibly stopping in the middle of
Since the device is installed on the machine body side, the strip spring force does not act on the upper turret but only on the machine body side, and the strip force can be increased. Also,
When the upper die is pulled out of the workpiece after drilling, the workpiece is prevented from being lifted and the surface pressure applied to the workpiece is reduced, so that drilling with no permanent distortion remains. Made it possible. Further, since the proper space distance from the upper surface of the lower mold to the lower surface of the stripper can be set by only one motion of the ram, the operation becomes extremely simple.

[0010]

EXAMPLE An example of the method of the present invention will now be described with reference to the drawings. FIG. 1 is a side view of a turret punch press machine for carrying out an example of a punching method for a soft material and a soft laminated material according to the present invention, and FIGS. 2 to 4 are upper surfaces of a lower die in a turret punch press machine to which the first invention is applied. From the upper die holder to the lower surface of the turret punch press machine in which the space in the vertical direction is made variable, and FIG. 5 shows the turret punch press machine in which another embodiment of the method of the present invention is implemented. Sectional view,
6 to 8 are sectional views showing the main parts of a turret punch press machine to which the second invention is applied.

In FIG. 1, reference numeral 1 is a turret punch press machine, 2 is a foot portion of the turret punch press machine, and a turret punch press machine having a frame 101 having the foot portion 2 as a press body has a plate-shaped metal material s. A table 3 for supporting a work material W which is a laminated material in which a foamed resin material c is adhered to
An X-axis positioning device 4 and a Y-axis positioning device 5 for positioning the workpiece W, a disc-shaped rotatable upper turret 102 having an upper mold assembly 36, and a rotatable mold having a lower mold 36 '. A turret device 116 including a lower turret 103, and the upper turret 1 is provided on the upper side of the frame 101.
Ram 13 for pressing upper mold assembly 36 of 02 from above
There is provided a press drive device 50 for vertically driving the. The upper turret 102 is rotatably supported by a bearing device 52 having a pair or a plurality of pairs of upper mold assemblies 36 mounted thereon and arranged on the frame 101, and the lower turret 103 has an upper mold assembly 36. Lower die (die) 3 paired with 36
6'is arranged and is rotatably supported by a bearing device (not shown) arranged on the frame 101.

The table 3 is provided on the slide frame 110 which is located below the pocket portion 2 and is arranged on the frame 101. The Y-axis positioning device is provided for the table 3. 5 is a rail 1 installed on the slide frame 110.
A Y-axis carriage 112 movably supported in the front-rear direction of the frame 101 via a rail 11, and a rail 113 mounted on the Y-axis carriage 112 to move the frame 101 in the left-right direction. An X-axis positioning device 4 by an X-axis carriage 114 that is freely supported, and a clamp for holding a workpiece W
And a turret device 1 for processing a workpiece W.
It is configured so that it can be arbitrarily positioned in the left-right and front-rear directions (X-axis and Y-axis) with respect to 16.

The upper die assembly 36 is embedded in the punch (upper die) 31, the punch head 32 that receives the pressing force and the pulling force of the ram 13, and the punch 31, and regulates the rotation direction of the punch 31. It comprises a pin 33 and a support spring 34 fitted to the punch head 32 and supporting the weight of the upper die assembly 36 itself. 37 is an upper mold holder which is formed by forming a screw on the outer periphery and accommodates and holds the upper mold assembly 36 so as to be slidable in the vertical direction and which is not rotatable itself but is slidable in the vertical direction, and 38 is an upper turret. A key 39 for restricting the rotation of the mold holder 37 disposed on the screw 102 is screwed to the upper mold holder 37 and is rotatable with respect to the upper turret 102, but is a drive ring arranged immovably in the vertical direction. The upper part of the outer circumference is a gear. Reference numeral 40 is a guide ring that guides the drive ring 39 rotatably but immovably in the vertical direction.

Reference numeral 50 is a press drive device, which is a hydraulic cylinder 12a.
And a piston 12 arranged in the hydraulic cylinder 12a, and a ram 13 connected to the piston 12 and movable in the vertical direction. The turret punch press machine presses the upper die assembly 36 in the vertical direction. It is attached to the main body frame 101.

Reference numeral 15 is a detection device for detecting the stroke position of the ram 13. In this embodiment, a potentiometer is used, and the sliding direction of the piston 12 to which the ram 13 is connected and the detection device 15 are inserted. The hydraulic cylinder 12a is set so that the sliding direction of the detection rod 16 arranged to move forward and backward is the same.
It is fixed to.

Reference numeral 17 denotes a sensor head mounted on the tip of the detection rod 16, urged by a spring 18 and abutting on the dog 19, 20 is guided by the hydraulic cylinder 12a, and the ram 1
A guide rod for preventing the rotation of the ram 3 and transmitting the vertical movement of the ram 13 to the dog 19, 21 is a connecting block for connecting the ram 13 and the guide rod 20, which is fixed to the ram 13 and also serves as the guide rod 20. It is connected.

61 is a servomotor mounted on the main body of the machine, 62
Is a pulley, 63 is a shaft erected on the bracket 64, and 65 is the shaft
The pulley attached to 63, the gear 66 is the same, and the pulley 67 is
A belt wound around 62 and 65, 68 is a shaft internally mounted so that it can freely rotate with respect to the piston 69 but operates integrally in the vertical direction, and 70 is a gear meshing with the gear 66. It is fitted on the upper part of the shaft 68,
A clutch gear 71 is fixed to the lower end of the shaft 68.

Reference numeral 72 is a spring case fixed to the upper end of the shaft 68, 73 is a spring interposed between the case 72 and the gear 70 to urge the shaft 68 upward, and 74 is an upper turret 102. Gears that are fitted to the drive ring 39, 75 are provided at the upper end of the gear 74, and the clutch gear 71
The gears meshing with the gears 61 to 75 constitute a transmission mechanism for rotating the drive ring 39.

An example of the turret punch press used in the punching method of the present invention is constructed as described above. The punching method together with its operation will be described below.

In the state shown in FIG. 2, if pressurized air is sent to the space b of the cylinder formed in the bracket 64 and containing the piston 69, the piston 69 and the shaft 68 are lowered against the repulsive force of the spring 73. Then, as shown in FIG. 3, the clutch gear 71 meshes with the gear 75. In this state,
If you drive the motor 61, its rotation will be
It is transmitted to the shaft 68 through the gears 66 and 70, and the shaft 68
Since the clutch gear 71 integral with 68 is rotated, the gear 74 coaxial with the gear 75 meshing with the clutch gear 71 is rotated, and the drive ring 39 is rotated.

The rotation of the drive ring 39 causes the upper mold holder 37, which is screwed into the drive ring 39, to rotate in the vertical direction because the rotation direction of the upper mold holder 37 is restricted by the key 38. The space in the vertical direction from the upper surface of 'to the lower surface of the upper mold holder-37 is changed. Here, the operating timing and operating range of the upper die holder-37 are
By controlling the motor 61, it can be set and held at an arbitrary position at an arbitrary timing.

FIG. 3 shows a state in which the drilling of the workpiece W has been completed. By supplying hydraulic fluid to the upper chamber A of the cylinder 12a, the ram 13 descends together with the piston 12, Work piece W by processing the upper die assembly 36
Press. At this time, the upper die holder-37 is also
By the rotational driving of the tool 61, the upper mold holder-37 lowers the workpiece W to a position in the range where permanent strain does not occur, and holds that position. Therefore, of the parts forming the upper die assembly 36, the part that affects the workpiece W with the punching operation is only the cutting edge part P of the punch 31, which is the minimum range. No large permanent set occurs on the outer circumference.

The upper die holder-37 is an upper die assembly.
When the punch 31 forming the part 36 is separated from the work material W, it is sufficient if the work material W is lowered to a position where no permanent strain is generated, but the work material W is slightly pressed to make a hole. When it is convenient to perform processing, the timing may be such that the upper mold holder-37 is lowered before the lower mold assembly 36 is lowered.

FIG. 4 shows the cylinder 12a after completion of the drilling process.
By supplying hydraulic operating oil to the lower chamber B of the
The ram 13 is raised together with the ram 12, the punch head 32 is pulled up by the ram 13, and the upper die assembly 36 is attached to the workpiece W.
The upper mold holder 37 is in the above-mentioned held position. When the upper die assembly 36 is pulled out, friction acts between the cutting edge portion P of the punch 31 and the cutting surface of the work material W, and the work material W tries to rise along with the cutting edge portion P of the punch 31. However, since the rising is restricted by the upper mold holder-37, the upper mold holder-37 is prevented from being lifted upward, and the contact area between the upper mold holder-37 functioning as a plate pressing portion and the workpiece W is Since it is much larger than the stripper 301 of the conventional upper die assembly 300 shown in FIG. 9, the surface pressure acting on the surface of the workpiece W is also small and the dent Q
Does not occur and permanent strain is less likely to occur.

FIG. 5 shows an embodiment using a vertically movable lid provided on the bottom surface of the upper turret 102.
Reference numeral 201 in the drawing is a lid that serves to change the vertical space from the upper surface of the lower die (die) 36 'to the lower surface of the upper turret 102, and a guide post 202 is erected on this lid 201.
The lid 201 is biased upward by a spring 203 guided by the guide post 202, and abuts against the lower surface of the upper turret 102.

Further, the guide rod 2 is provided at the center of the lid 201.
04 is erected, and is guided slidably in the vertical direction by guide metals 206 and 207 installed inside the rotary shaft 205 of the upper turret 102. 208 is a servomotor mounted on the machine body, 209 is a
The pulley 210 is a pulley that is rotatable by itself but is fixed in the vertical direction and is axially supported. 211 is a belt. 212 is a push rod. Pulley 210 is the upper end of the push rod 212. The belt 211 is wound around the pulleys 209 and 210. Further, a screw 213 for operating the push rod 212 itself in a vertical direction by the rotation of the pulley 210 and a spline 214 at the lower portion are formed on the upper end of the push rod 212, and a bearing case 215 is formed. It is adapted to be fitted with a spline provided in the above to regulate the rotation of the push rod 212.

In the state of FIG. 5, when the servo motor 208 is driven in the direction in which the push rod 212 moves downward, the rotation thereof causes the pulleys 209 and 210 to rotate. The push rod 212 includes a screw 213 provided on the upper end of the push rod 212 and a pulley.
By the action of the screw part of 210, it moves downward, and the lid 201 moves downward against the repulsive force of the spring 203 via the guide rod 204, so that the upper surface of the lower die (die) 36 'moves upward. The change is made so that the vertical spatial distance to the lower surface of the turret 102 becomes smaller. The operating range of the lid 201 can be set and held at any position at any timing by controlling the servo motor 208. Also,
When increasing the space distance, the servo motor 208
Should be driven in a direction in which the push rod 212 moves upward.

Next, an example of the second embodiment of the present invention will be described with reference to FIGS. In FIG. 6, an upper die assembly 361 includes a punch (upper die) 362 having a cutting edge portion P at its tip, and a punch head 3 that receives a pressing force of a ram 13.
63, a stripper 364 which is a plate pressing member provided with a protrusion 364a for abutting against a stopper described later on the outer periphery of the upper part, a punch 362 when the ram 13 is compressed as the ram 13 rises
Strip spring 365, which separates the workpiece W from the workpiece W,
The guide 371 is formed by a punch guide 366 that guides the punch 362 to the stripper 364, and is lifted upward by a guide post 371 standing on the upper turret 102, a spring 372 guided by the guide post 371, and a tool lifter 373. And the upper limit is regulated. 6 to 8, the same reference numerals as those in FIGS. 2 to 5 denote the same parts.

Further, 381 is a stopper cylinder fixedly arranged on the frame 101, and 382 is a stopper which abuts so that the stripper 364 can be received while it is descending and is prevented from descending further. It is immovable in the direction, but is slidably accommodated in the stopper cylinder 381 in the vertical direction. The detection of the lowered position of the stopper-364 is performed by, for example, between the stopper-364 and the stopper cylinder-381, the stroke detection means of the ram 13 and the stroke.
That is, the detection can be performed by providing each member from the detection device 15 to the connection block 21.

Then, the stripper 364 is the punch head 3
The distance L _{1 in} the vertical direction from the lower surface of the stripper 364 to the upper surface of the foamed resin c of the workpiece W is as follows: The position of the stopper 382 is set so as to be substantially the same as L ₂ or a compression amount that does not cause permanent strain in the workpiece W.

An example of the turret punch press used in the punching method according to the second aspect of the present invention is constructed as described above. The action and the punching method will be described below.

FIG. 7 shows a state in which the drilling of the workpiece W has been completed. At the time of drilling, if hydraulic oil is supplied to the upper chamber A of the cylinder 12a, the piston 1
2, the ram 13 descends, the lower end of the ram 13 comes into contact with the punch head 363 to lower the upper die assembly 361, and as the descent progresses, the outer peripheral protrusion 364 of the stripper 364 is advanced.
The a comes into contact with the stopper 382, and the descent of the stripper 364 is stopped. Then, when the descent of the ram 13 progresses further,
The strip spring 365 is compressed to increase the repulsive force for pulling the punch 362 from the workpiece W,
The lower end of the cutting edge portion P of 362 descends to a position where it penetrates the workpiece W, and drilling is completed. That is, the stripper 364 descends to a position where permanent deformation does not occur in the workpiece W,
Since it is stopped at that position, a large permanent strain does not occur in the portion of the workpiece W that contacts the outer peripheral portion of the cutting edge portion P.

FIG. 8 shows the cylinder-12 after the drilling process is completed.
By supplying hydraulic oil to the lower chamber B of a, the ram 13 is raised together with the piston 12, and the strip spring 36
The punch 362 is pulled up by the repulsive force of 5 and the punch 36
2 shows a state in which 2 is pulled out from the workpiece W, and the stripper 364 is held at the position shown in FIG.

When the punch 361 is pulled out, friction acts between the cutting edge portion P of the punch 361 and the cutting surface of the workpiece W, and the workpiece W rises along with the cutting edge portion P. However, since the upper movement is restricted by the stripper 363, it cannot be lifted upward.

Workpiece material W according to the second aspect of the present invention
Since the hole drilling is performed as described above, no permanent strain is generated in the workpiece W after the hole drilling, and the hole peripheral portion of the workpiece W has the same surface as other portions. To be kept. Although the stopper 382 in the above is a cylinder type, it is not limited to this and may be an electric type, and if the thickness of the workpiece W does not change, L ₂ , that is, the lower surface of the stripper 382. To the foamed resin c of the workpiece W
The distance to the upper surface of the stopper may be fixed and the stopper 382 may be immovable in the vertical direction.

[0036]

The present invention is as described above, and the method for punching a soft material and a soft laminated material by the turret punch press of the present invention is capable of punching several dozen types of holes with several types of dies. By utilizing the advantage of the turret punch press that it is possible to drill holes in combination, it is possible to punch holes in permanent materials due to plate pressing without leaving permanent distortion in soft materials or laminated materials to which foamed resin materials have been adhered Since drilling can be performed, it is possible to use these materials even for processed products of a wide variety of small quantities, and the applications are expanded, and the range of applicable materials for the turret punch press machine is expanded, making the turret punch press machine more versatile. improves.

[Brief description of the drawings]

FIG. 1 is a side view of an example of a turret punch press for implementing a method for punching a soft material and a soft laminated material according to the present invention.

FIG. 2 is a cross-sectional view showing a main part before drilling by a turret punch press machine to which the first invention is applied.

FIG. 3 is a cross-sectional view showing a main part at the time of punching processing by the turret punch press machine of FIG.

FIG. 4 is a cross-sectional view of a main part showing a state in which an upper die is pulled out from a work material from the state of FIG.

FIG. 5 is a cross-sectional view showing a main part of a turret punch press machine for carrying out a drilling method according to another example of the first invention.

FIG. 6 is a cross-sectional view of a main part showing a state in which a boring process is started by a turret punch press machine to which the second invention is applied.

FIG. 7 is a cross-sectional view of an essential part showing a state immediately after finishing the drilling process from the state of FIG. 6;

8 is a cross-sectional view of a main part showing a state in which an upper die has been pulled out of a work material from the state of FIG. 7.

FIG. 9 is a sectional view showing an upper die assembly and a stripper for the same in a conventional turret punch press.

[Explanation of symbols]

 1 Turret Punch Press Machine 2 Folding Area 3 Table 4 X Axis Positioning Device 5 Y Axis Positioning Device 101 Main Frame 102 Upper Turret 103 Lower Turret 110 Slide Frame 111 Rail 112 Y Axis Carriage 113 Rail 114 X-axis carriage 115 Clamp 116 Turret device 12 Piston 12a Hydraulic cylinder 13 Ram 31 Punch (upper die) 36 Upper die assembly 36 'Lower die (die) 37 Upper die holder-50 Press drive device 201 Lid 361 Upper Mold assembly 362 Upper mold (punch) 363 Punch head 364 Stripper-365 Strip spring 366 Punch guide 371 Guide post 372 Spring 373 Tool lifter 381 Stopper-cylinder-382 Stopper-W Work material s Metal material c Soft material P Punch (upper mold) cutting edge Q Recess

Claims (7)

[Claims] 1. An X, Y positioning device for positioning a plate-shaped workpiece on an X, Y plane, an upper turret for mounting an upper die, a lower turret for mounting a lower die, and an upper turret. A press drive device including an upper die holder for housing and holding the upper die slidably in the vertical direction, an upper die and a lower die arranged on the upper and lower turrets, and a ram for pressing the upper die. In a turret punch press consisting of: a lower die upper surface to an upper turret lower surface or an upper die holder, which is provided for positioning the workpiece between the lower die and the upper die.
A means for changing the space in the vertical direction up to the lower surface is provided, and when positioning the work material between the lower mold and the upper mold, the space is widened, and the upper space is formed during drilling and after drilling. A method for punching a soft material and a soft laminated material by a turret punch press machine, characterized in that the space is narrowed when the die is pulled out from the work material. 2. A means for varying the space between the upper mold and the lower mold is to raise the upper mold holder to widen the space from the upper surface of the lower mold to the lower surface of the upper mold holder, 2. The method according to claim 1, which is a means for narrowing the space by lowering the die holder or raising the lower die. 3. A means for varying the space between the upper mold and the lower mold is configured to raise a lid provided on the bottom surface of the upper turret so as to be vertically movable so that the space from the upper surface of the lower mold to the lower surface of the upper turret is increased. The drilling method according to claim 1, which is a means that widens the space and lowers the lid to narrow the space. 4. The vertical distance from the upper surface of the lower mold to the lower surface of the upper turret or from the upper surface of the upper mold holder to the lower surface when the space is narrowed is changed and controlled according to the thickness of the work material. The drilling method according to any one of 1 to 3. 5. An X, Y positioning device for positioning a plate-shaped workpiece on an X, Y plane, an upper turret for accommodating and holding one or a plurality of upper molds in a vertically slidable manner, and the upper turret. A lower turret for mounting a lower die paired with, one or a plurality of upper dies provided with at least a plate pressing portion and a cutting blade portion arranged in the upper turret, and a lower die arranged in the lower turret, In a turret punch press machine comprising a press drive device having a ram for pressing the upper die downward,
A means for changing the vertical space from the upper surface of the lower mold to the lower surface of the upper mold, which is provided for positioning the work material between the lower mold and the upper mold, is provided, The space is widened when positioning between the mold and the upper mold, and the space is narrowed at the time of drilling and when the upper mold is pulled out from the workpiece after the drilling. For punching soft materials and soft laminated materials using a turret punch press machine. 6. The stopper for changing the space between the upper mold and the lower mold is a stopper for abutting the plate pressing part of the upper mold so as to be received by the press body side when the upper mold descends. A device is provided, and when the upper die is pressed downward by the press drive device and descends, the lower end of the cutting edge portion of the upper die descends the workpiece to the position, but the lower die of the upper die The plate pressing member is made to abut on the main body of the press machine while descending and is prevented from further descending, and when the lower end of the plate pressing member abuts the workpiece, the punching process is performed. Drilling method. 7. The punching according to claim 5, wherein the position at which the plate pressing portion of the upper die is prevented from descending is determined by position control in which the stopper device is changed in the vertical direction according to the thickness of the workpiece. Method.