JPH11254395A - Punching machine unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To conduct changing work of a punch and a die with a punching unit fitted on the punch as it is for improved productivity of a punching device by increasing the fitting precision of a punch holder and/or a die holder. SOLUTION: This punching machine unit involves a punch setting part 20 and die setting part 10 on the body of the unit, and is formed so that a punch holder 26 fitted on the punch setting part 20, and a die holder 14 fitted on the die setting 10 may be arranged, facing each other vertically. The die setting part 10 has a fitting hole 11 which fits and retains the die holder 14, the die holder 14 is inserted so as to be capable of being inserted and removed into/ from the fitting hole 11 from the above, and a cylindrical retainer 13 whose micro-diameter balls 13a are rotatably-scattered so as to protrude therefrom is set in the fitting hole 11. The outer-periphery surface of the die holder 14 is brought into sliding contact with the balls 13a of the retainer 13, and in the punch setting part 24, the supporting rod of a punch ram 22 is fitted on the retainer 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a punching unit, and more particularly, to a punching device for punching a pattern or a reference hole in a printed circuit board, a flexible film, a metal foil, a ceramic green sheet or the like. Regarding the unit to be installed (punching unit), more specifically, fine diameter (30 to
The present invention relates to a punch unit suitable for a unit using a punch having a diameter of 100 microns (micro-punching unit).

[0002]

2. Description of the Related Art A conventional punching unit generally has a punch setting section and a die setting section in a unit body, and a punch holder attached to the punch setting section and a die holder attached to the die setting section are vertically opposed. However, it is extremely important to set the punch mounted on and supported by the punch holder and the die mounted on the die holder concentrically in order to improve the punching accuracy. In addition, the punch and die are replaced each time a hole with a different diameter or shape is punched, but at the time of replacement, it is necessary to align the center of the punch and the die with each other. there were. Therefore, when replacing the punch and the die, remove the punching unit or micro-punching unit (hereinafter referred to as the punch unit) from the punching machine for alignment work, attach each punch unit to the alignment setter, and set the punch and die. After the replacement, the centering operation was performed. Further, after the centering operation, it is necessary to mount and fix the punch unit while positioning the punch unit again at a predetermined position of the punching device.

[0003]

However, the conventional replacement involves the work of removing each punch unit from the punching device, the alignment work, and the mounting work. Therefore, the replacement work requires time and skill and the production of the punching device is required. It is a cause of sex decline. In particular, in the case of the micropunch unit, as disclosed in Japanese Patent Application Laid-Open No. 9-85690, a large number of units are arranged at a small pitch, and adjacent units are connected to each other by a parallel spacing adjusting member. In addition, there have been problems such as a large number of troubles in the work of attaching and detaching each punch unit from the punching device. In view of the above circumstances, the present invention improves the mounting accuracy of a punch holder and / or a die holder, thereby making it possible to exchange a punch and a die while the punch unit is mounted on the punching device, and to improve the productivity of the punching device. The purpose is to improve.
Further, the present invention eliminates the need for alignment work by increasing the mounting accuracy of punches and dies, and further facilitates the work of replacing the punches and dies.

[0004]

According to the present invention, a unit body has a punch setting section and a die setting section, and a punch holder attached to the punch setting section and a die holder attached to the die setting section are vertically movable. In a punching unit arranged in an opposed manner, a means for increasing the mounting accuracy of the die holder and facilitating exchangeability, wherein the die setting portion has a mounting hole for mounting and supporting the die holder,
A die holder is inserted into the mounting hole so as to be able to be pulled out and inserted from above, and a cylindrical retainer in which fine-diameter balls protrude inward and outward and are rotatably scattered is mounted in the mounting hole. The outer peripheral surface of the die holder is brought into sliding contact with the die holder (claim 1).

According to another aspect of the present invention, there is provided a punch setting unit having a punch holder via a punch ram, wherein the punch ram is mounted with a higher accuracy and the die holder is easily exchangeable with the punch ram. The part has a support hole for mounting and supporting the punch ram, and the support rod of the punch ram is inserted into the support hole so that it can be inserted and removed from above, and a fine-diameter ball projects and rotates inside and outside the support hole. A cylindrical retainer interspersed as much as possible was mounted, the outer peripheral surface of the support rod of the punch ram was slid on the ball of the retainer, a punch holder was provided at the lower part of the punch ram, and a punch driving mechanism was attached at the upper part. It is a feature (claim 2).

The third aspect of the present invention is a means for eliminating the need for aligning the punch and the die, particularly after replacing the die and the die, wherein the die is tightly attached to the die holder,
A guide bush through which the punch is slidably inserted is tightly attached to the punch holder via a pad ring.

[0007]

According to the first aspect of the present invention, with the punch unit attached to the punching device, the die holder is taken out together with the die from the die setting section by lifting the die holder after releasing the support member of the die holder. ,
After that, the die is replaced by inserting the die holder with the new die attached. The newly inserted die holder
The ball is slightly elastically deformed while slidingly contacting the ball of the retainer on its outer peripheral surface, so that straightness is maintained and the ball is tightly mounted on the retainer.

According to a second aspect of the present invention, in a state where the punch unit is attached to the punching device, the punch ram is lifted up after releasing the support member of the punch ram integral with or integral with the punch holder, so that the punch holder together with the punch is lifted. Is removed from the punch setting section, and then the punch is replaced by inserting the support rod of the punch ram on which a new punch is mounted into the support hole. The support rod of the newly inserted punch ram is also kept straight by the retainer ball and tightly mounted on the retainer, similarly to the above-described die holder. Further, when the punch ram is removed from the punch setting section together with the punch holder, the upper part of the die setting section is opened, so that the work of replacing the die holder is facilitated.
Even if the die holder is long, it does not hinder the replacement.

According to the third aspect of the present invention, the die is tightly attached to the die holder and the punch is tightly attached to the punch holder. And the axis of the die is set concentrically.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, an embodiment of the present invention will be described. In FIG. 1, U is a punch unit which exemplifies a unit using a fine-diameter punch.
One or a plurality of punch units U are mounted on a work table of the punching device A at predetermined intervals. The punch unit U is connected to the upper case via a notch space 1 for moving the work formed in the upper and lower central portions.
It has a flat U-shaped flat thin shape composed of a lower case 2a and a lower case 2b. A die setting unit 10 is arranged on the lower case 2b on one end side, and a punch setting unit 20 is arranged on the upper case 2a.

The die setting portion 10 has a mounting hole 11 penetrating vertically through the lower case 2b, and a support protrusion 12 protruding downward at an upper outer side of the mounting hole 11. A cylindrical retainer 13 is fitted and mounted in the die setting portion 10 in the mounting hole 11, and a die holder 14 is fitted in the retainer 13.
And the flange 14a of the die holder 14 is brought into contact with and supported below the support projection 12 by a rotation operation.

The mounting hole 11 has an inner peripheral shape in which a large-diameter upper half portion and a small-diameter lower half portion are connected to each other.
Has a shape adapted to the inner peripheral surface of the mounting hole 11 and is fitted into the mounting hole 11. The retainer 13 is a fine-diameter ball
Have a form in which they are rotatably scattered and held in such a state that they protrude from the inner and outer surfaces, respectively, and the outer peripheral surface of the ball 13a is in sliding contact with the inner peripheral surface of the mounting hole 11. This ball 13
a, 13a... are arranged in at least 3 to 4 rows, and the arrangement in the rows is substantially the entire upper and lower areas or an appropriate partial area, and in the embodiment, only the upper and lower parts are minimized so as to be effective. An example in which they are arranged will be described.

The die holder 14 has an outer shape substantially conforming to the inner diameter of the retainer 13.
The ball 13a is slid in contact with the ball 13a in a state of being inserted therein, and more specifically, is joined to the outer peripheral surface of the die holder 14 so that the ball 13a is slightly elastically deformed. As a result, the die holder 14
Straightness at the time of insertion of the die holder 14 and the die holder 14
Is tightly inserted into the retainer 13 without any clearance, and the centering of the die holder 14 in the die setting section 10 is ensured. A die 16 is mounted on the upper end fitting portion 15 of the die holder 14, and the die 16 is tightly attached to the fitting portion 15. That is, the fitting portion 15 and the die
The die 16 is mounted in a state where a clearance is interposed between the die 16 and the die 16 and the die 16 is fitted and fixed with little clearance, instead of being tightened with screws. Thereby, centering between the die holder 14 and the die 16 is also ensured. Although not shown, attached members such as an air blowing passage for facilitating separation of the punched waste and a discharge hose for the punched waste are detachably attached to the die holder 14.

Next, in the punch setting section 20, support holes 21, 21 penetrating vertically through the upper case 2a are formed.
The punch ram 22 is attached by inserting the support rod 23 of the punch ram 22 into the punch ram 22, and the punch ram 22 is urged upward with a spring member 24 interposed between the upper case 2a and the punch ram 22. In addition, a support table 40 is detachably mounted on the upper surface of the upper case 2a with bolts 41 on the punch setting section 20, and a punch ram is provided.
A punch pack 42 that protrudes above the top 22 and moves the punch ram 22 up and down is provided on the support base 40. This punch pack 42
Is to adjust the initial position of the punch ram 22 according to the thickness of the perforated work.

The punch ram 22 has a vertical portion 22a hanging down from the front surface of the upper case 2a and a lower end of the vertical portion 22a.
A horizontal portion 22b protruding upward from the mounting hole 11 is integrally provided, a punch driving mechanism 25 is provided in the vertical portion 22a, and a die holder 26 is provided in the horizontal portion 22b. The driving mechanism 25 has a driving unit 27 using air pressure disposed on a support 28, and drives a punch 30 attached to the punch holder 26 by a hammer 29 connected to the driving unit 27. The support 28 of the striking mechanism 25 is fitted in a groove on the front surface of the vertical portion 22a of the punch ram 22, is mounted so as to be able to move up and down and to be pulled out upward, and is fixed at a predetermined position by a bolt 28a. The striking mechanism 25 can finely adjust the vertical position of the support 28 by the micrometer 31, so that the initial position of the punch 30 can be finely adjusted.

The punch holder 26 is a horizontal part of the punch ram 22.
Although a case where the guide ring is formed integrally with the punch holder 22b is exemplified, a pad ring 32 is fixed to the punch holder 26, and the guide bush 33 is integrally fixed to the pad ring 32 in a state where the guide bush 33 is centered. The punch 30 is slidably inserted into the bush 33. Accordingly, the punch 30 is inserted into the guide bush 33 and set in a centered shape on the punch holder 26. The punch holder 26 is arranged so as to be vertically opposed to the die holder 14 at the time of initial mounting, and is set using a jig or the like so that the holders 26 and 14 are concentric. In the figure, 34 is a spring, and 35 is a stripper.

The support hole 21 into which the support rod 23 of the punch ram 22 is inserted is rotatable in a state in which fine-diameter balls 36a, 36a,. Is mounted, and the support rod 23 of the punch ram 22 is inserted and supported in the retainer 36. The fitting between the support rod 23 of the punch ram 22 and the retainer 36 is performed by the die holder 14 and the retainer described above.
The description is omitted because it is the same as the fitting of 13. Reference numeral 37 provided in the support hole 21 is an upwardly biased spring that receives the retainer 36.

The punch and die exchange operation will be described with reference to FIG. 2. First, with the punch unit U attached to the punching device, the support 40 in the punch setting section 20 is first bolted.
The punch ram 22 is removed from the punch setting section 20 by removing the punch ram 22 from the punch setting portion 20 by pulling up the punch ram 22 and then pulling out the support rod 23 from the support hole 21. The punching mechanism 25 is further removed from the removed punch ram 22 by pulling up the support 28, and the punch 30
From the punch holder 26 and replace it with a new one.
On the other hand, since the upper part of the die setting part 10 is opened by removing the punch ram 22, the die holder 14 is rotated to
After detaching a from the support projections 12, the die holder 14 can be pulled out upward. Therefore, the die of the die holder 14 that has been pulled out is replaced with a new die, or the entire die holder is replaced with a new die.

Thereafter, the die holder 14 is inserted again into the retainer 13 of the mounting hole 11 of the die setting section 10, and the die holder is rotated to hook and support the flange portion 14a on the support projection 12, thereby setting the die holder 14 to the die setting. Set in part 10. Further, the punch ram 22 has the support rod 23 inserted into the retainer 36 of the support hole 21 and the
To the punch setting section
Set to 20.

Accordingly, the punch 30 and the die 16 can be exchanged while the punch unit U is attached to the punching device A, and the fitting between the die holder 14 and the retainer 13 and the support rod 23 of the punch ram and the retainer 36 are performed. The die holder 14 and the punch ram support rod 23 maintain straightness and are tightly mounted on the retainers 13 and 36 without clearance by the fitting of the die holder 14 and the punch ram. The same concentricity as in the initial setting is secured in the punch setting unit 20 and the punch setting unit 20 is reset. Also, since the die 16 is mounted on the die holder 14 and the punch 30 is mounted on the punch holder 26 tightly without any clearance, the concentric state of the punch and the die after the replacement operation is also ensured.

In the above embodiment, the punch holder 26 is integrated with the punch ram 22 as an example. The punch holder 26 may be separately provided and fixed to a horizontal portion of the punch ram. In this case, the initial mounting of the punch holder and the punch ram is performed, as shown in FIG. 3, by mounting the die holder 14 before the die 16 is mounted on the die installation portion 10, fitting the set jig 45 to the die holder 14, and Punch holder 44 on jig 45
The punch holder 44 is fixed to the horizontal portion 22b of the punch ram 22 with set bolts 46 while maintaining this state. As a result, the punch holder 44 is integrated with the punch ram 22 in such a manner that the punch holder 44 can be aligned with the die holder 14, and the manufacture of the punch holder is easier than in the case where the punch ram is integrated. When using the set jig 45, the work may be performed with the die holder 26 detached from the die setting unit 10.

Next, FIG. 4 shows another embodiment of the present invention, in which a punch setting section 50 includes a punch ram 22 as in the above-described embodiment.
A punch holder 51 is provided, and a plunger 53 in which a punch 52 is fixed is mounted on the punch holder 51 together with a punching mechanism 54 so as to be able to be pulled out and inserted from above. In FIG. 3, reference numeral 55 denotes a retainer of the embodiment shown in FIG.
A retainer that acts in the same manner as 13 or 36. The retainer 55 ensures the straightness of the plunger 53, that is, the punch 52, and the tightness (centering state) with respect to the punch holder 51. In this embodiment, when the punch and the die are exchanged, the plunger 53 is moved together with the striking mechanism 54.
Is extracted upward, and then the die holder 61 attached to the die setting unit 60 is extracted, and the die 62 is replaced. Since the die setting unit 60 needs to attach and detach the die holder 61 to and from the mounting hole 63 through the notch space 1 of the punch unit U, except that the length of the die holder 61 is set to be not more than the notch space 1. There is no need to change the configuration.

[0023]

According to the first aspect of the present invention, it is possible to remove the die holder from the die setting section and replace it with a new die while keeping the punch unit attached to the punching device. Is tightly mounted with no clearance by a retainer, and concentricity of the die holder with respect to the die setting portion is ensured. Further, according to the second aspect, the punch can be replaced while the punch unit is attached to the punching device, and the concentricity of the punch unit with respect to the punch setting section is ensured. Therefore, the productivity of the punching device is remarkably improved as compared with the related art in which the punch unit is detached from the punching device every time the punch and the die are replaced. In particular, the effect is remarkable in a punching device in which a plurality of punch units are connected and set by an interval adjusting member or the like.

According to the third aspect, since the die and the die holder and the punch and the punch holder are respectively set concentrically, there is no need for the centering work after the die and punch replacement work. The replacement work can be further facilitated and the productivity can be further improved.

[Brief description of the drawings]

FIG. 1 is a side view of a punching machine unit according to the present invention, in which main parts are cut away.

FIG. 2 is a side view showing a state where a die holder and a punch holder are replaced.

FIG. 3 is a sectional view of a means for setting the punch holder to the punch ram when the punch holder is separate from the punch ram;

FIG. 4 is a side view of a punching machine unit according to another embodiment of the present invention, in which main parts are cut away. In the figure, U: punch unit A: punching device 10: die setting unit 11: mounting hole 12: support projection
13: Retainer 13a: Ball 14: Die holder 14a: Flange
16: Die 20: Punch setting part 21: Support hole 22: Punch ram 25: Driving mechanism 26: Punch holder 30: Punch
36: Retainer 36a: Ball 50: Punch setting part 51: Punch holder 52: Punch 53: Plunger 54: Driving mechanism 55: Retainer 60: Die setting part 61: Die holder 62: Die
63: Mounting hole

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] February 26, 1999

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0003

[Correction method] Change

[Correction contents]

[0003]

However, the conventional replacement involves the work of removing each punch unit from the punching device, the alignment work, and the mounting work. Therefore, the replacement work requires time and skill and the production of the punching device is required. It is a cause of sex decline. In particular, in the case of the micropunch unit, as disclosed in JP-A-9-85690, a large number of units are arranged at a small pitch, and adjacent units are connected to each other by a parallel spacing adjusting member. In addition, there have been problems such as a large number of troubles required for attaching and detaching each punch unit from the punching device. Accordingly, the present invention has been made in view of the above-described conventional circumstances , by improving the mounting accuracy of punches and dies.
Eliminates the need for centering work and facilitates punch and die replacement work.
The purpose is to make it even easier . The present invention also provides a punch holder and / or a die holder mounting precision.
The punch unit to the punch
Punch and die exchange work is possible with the
This improves the productivity of the hole device .

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction contents]

[0004]

According to the present invention, the unit main body has a punch setting section and a die setting section, and the punch setting section has a punch holder attached via a punch ram, and a punch holder attached to the die setting section. in drilling machine units and die holders are disposed vertically opposite shape, said underwear
The punch is set while maintaining the straightness of vertical movement.
The die is tightly mounted on the die holder.
The punch is slidably inserted through the punch holder.
Guide bush to be inserted tightly via pat ring
It is attached (claim 1).

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0005

[Correction method] Change

[Correction contents]

[0005] The present invention, the punch setting portion has a support hole for supporting the mounting of the path <br/> Nchiramu, to the support hole
The support rod of the punch ram is inserted so as to be able to be pulled out and inserted from above, and a cylindrical retainer in which fine-diameter balls protrude inside and outside and are rotatably scattered is mounted in the support hole,
An outer peripheral surface of the support rod of the punch ram is slidably contacted with the ball of the retainer, a punch holder is provided at a lower portion of the punch ram, and a punch driving mechanism is mounted at an upper portion of the punch ram (claim 2).

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction contents]

[0006] In a third aspect of the present invention, the die setting unit is a die setting unit.
Has a mounting hole for mounting and supporting the holder.
The die holder is inserted so that it can be pulled out and inserted from above.
A fine-diameter ball protrudes in and out of the hole and can be rotated
A cylindrical retainer scattered around is attached to this retainer.
The outer peripheral surface of the die holder is brought into sliding contact with the ball of the knives .

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

[0007]

According to the first aspect of the present invention, since the die is tightly mounted on the die holder and the punch is closely mounted on the punch holder, the die holder and the punch ram can be accurately mounted on the respective setting portions. Thereby, the axes of the punch and the die are set concentrically.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction contents]

According to a third aspect of the present invention, there is provided a punch unit.
With the die attached to the punching device,
And then pull up the die holder.
Remove the die holder together with the die from the die setting section,
Then insert the die holder with the new die
Replace the die. The newly inserted die holder
While sliding on the retainer ball on the outer peripheral surface,
The straightness is maintained by slightly deforming the
And tightly attached to the retainer.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0015

[Correction method] Change

[Correction contents]

The punch ram 22 has a vertical portion 22a hanging down from the front surface of the upper case 2a and a lower end of the vertical portion 22a.
A horizontal portion 22b protruding upward from the mounting hole 11 is integrally provided, a punch driving mechanism 25 is provided in the vertical portion 22a, and a punch holder 26 is provided in the horizontal portion 22b. The driving mechanism 25 has a driving unit 27 using air pressure disposed on a support 28, and drives a punch 30 attached to the punch holder 26 by a hammer 29 connected to the driving unit 27. The support 28 of the striking mechanism 25 is fitted in a groove on the front surface of the vertical portion 22a of the punch ram 22, is mounted so as to be able to move up and down and to be pulled out upward, and is fixed at a predetermined position by a bolt 28a. The striking mechanism 25 can finely adjust the vertical position of the support 28 by the micrometer 31, so that the initial position of the punch 30 can be finely adjusted.

[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction contents]

In the above embodiment, the punch holder 26 is integrated with the punch ram 22 as an example. The punch holder 26 may be separately provided and fixed to a horizontal portion of the punch ram. In that case, the initial installation of the punch holder and punch ram, as shown in FIG. 3, the die holder 14 before mounting the die 16 is attached to the die set unit 10, with mutually fitting the setting jig 45 in the die holder 14 Punch holder 44 on jig 45
The punch holder 44 is fixed to the horizontal portion 22b of the punch ram 22 with set bolts 46 while maintaining this state. As a result, the punch holder 44 is integrated with the punch ram 22 in such a manner that the punch holder 44 can be aligned with the die holder 14, and the manufacture of the punch holder is easier than in the case where the punch ram is integrated. When using the set jig 45, the work may be performed with the die holder 14 detached from the die setting unit 10.

[Procedure amendment 10]

[Document name to be amended] Statement

[Correction target item name] 0023

[Correction method] Change

[Correction contents]

[0023]

According to the first aspect of the present invention, a die and a die are provided.
Holder and punch and punch holder are concentric
After setting the die and punch,
No need for centering work, so replacement work is easy
At the same time, productivity can be improved. Further, according to the second aspect, the punch can be replaced while the punch unit is attached to the punching device, and the concentricity of the punch unit with respect to the punch setting section is ensured. Therefore,
The productivity of the punching device is remarkably improved as compared with the conventional method in which the punch unit is detached from the punching device every time the punch and the die are replaced. Particularly in a punching device in which a plurality of punch units are connected and set by an interval adjusting member or the like,
The effect is remarkable.

[Procedure amendment 11]

[Document name to be amended] Statement

[Correction target item name] 0024

[Correction method] Change

[Correction contents]

According to a third aspect of the present invention, there is provided a punch unit.
Set the die holder with the die attached to the punch
It is possible to pull out from the part and replace it with a new die
Yes, and new die holder is cleared by retainer
It is mounted tightly without a lance, and
The concentric shape of the holder is secured.

Claims (3)

[Claims] 1. A punching machine unit having a punch setting part and a die setting part in a unit main body, wherein a punch holder attached to the punch setting part and a die holder attached to the die setting part are vertically arranged to face each other. The die setting portion has a mounting hole for mounting and supporting a die holder, a die holder is inserted into the mounting hole so as to be able to be pulled out and inserted from above, and a ball having a fine diameter projects in and out of the mounting hole. A cylindrical retainer scattered rotatably is attached,
A perforator unit, wherein an outer peripheral surface of the die holder is slid on the ball of the retainer. 2. The punch setting section is provided with a punch holder via a punch ram, and the punch setting section has a support hole for mounting and supporting the punch ram, and a support rod of the punch ram is pulled out from above in the support hole. A cylindrical retainer in which fine-diameter balls protrude inwardly and outwardly and are rotatably scattered is mounted in the support hole, and the retainer balls slide the outer peripheral surface of the support rod of the punch ram. 2. The punching unit according to claim 1, wherein the punch ram is provided with a punch holder at a lower portion of the punch ram, and a punch driving mechanism is mounted at an upper portion of the punch ram. 3. The die holder is tightly mounted on the die holder, and a guide bush for slidably penetrating the punch is closely mounted on the punch holder via a pat ring. A perforator unit as described.