JPH11320493A - Sheet material punching device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To push a punch into a punch guide by means of an eccentric cam and to forcibly pull up the punch from the guide, without using a cam holder or a presser plate. SOLUTION: This punching device is provided with a punch 52 attached to a punch guide 16 and an eccentric cam 30 for pushing/moving the punch 52. The peripheral surface of the punch 52 is flattened from both sides toward the axial line of the punch 52, while an engaging pin 22 is projected/installed from/in a flattened part 52a. In the eccentric cam 30, a pair of large diameter parts 26 are formed at both ends of a cylindrical body and leaving a space slightly larger than the thickness of the flattened part 52a. On the surfaces facing with each other of the large diameter part 26, an annular, recessed groove 28 is formed. In the punch 52, the flattened part 52a goes into the large diameter part 26, while the engaging pin 22 penetrates into the recessed groove 28 of the large diameter part 26 in a freely slidable manner so as to be connected with the eccentric cam 30 as an integrated body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet material punching device for punching a binding hole in a sheet material such as a sheet of paper or a synthetic resin sheet.

[0002]

2. Description of the Related Art Conventionally, a sheet-like perforation in which a binding hole for a file is perforated in a sheet material such as a paper which is built in office equipment such as a copying machine and has been subjected to a process such as printing by the office equipment. Many devices have been developed. An example of this sheet-shaped punching device is disclosed in Japanese Patent Application Laid-Open No. H08-025292. An outline of this sheet-shaped punching device will be described with reference to FIG. 18. An eccentric cam 54 fixed to a drive shaft 50 and reciprocatingly driving a punch 52, a cam holder 56 mounted on the outer periphery of the eccentric cam 54, and a punch 52 It has a punch guide 58 to be fitted, and an L-shaped pressing plate 60 for preventing deformation and horizontal rotation of the cam holder 56. The cam holder 56 having a horizontal D-shape is formed using a metal material or a resin material, and has a configuration in which the shape is not deformed. The cam holder 56 has a portion formed in a straight line fixed to the head of the punch 52, and the portion formed on the curved surface is located upward.

[0003] The feature of this application is that, in the previous sheet-like punching device, the above-described cam holder 56 is provided with a punch 52.
Simply insert the cam holder 56 and punch 5
2 is not particularly fixed, so that the cam holder 56
When the eccentric cam 54 rotates while sliding inside, the cam holder 56 swings and rotates around the axis of the punch 52, and collides with, for example, a screw for fastening the eccentric cam 54 to the drive shaft 50, and eccentric cam 54 May not rotate. That is, the eccentric cam 54 makes point contact with the inner surface of the cam holder 56, and the number of contact points is usually two at most.
In particular, the contact point between the top dead center and the bottom dead center is on the axis of the punch, and the cam holder 56 rotates about this axis. Further, even when the cam holder 56 and the punch 52 are fixed, the punch 52 is a cylindrical body and rotates within the punch guide 58, and the cam holder 56 also rotates. In that the above-mentioned holding plate 60 is provided. As a result, the non-circular outer peripheral surface of the punch guide 58 and the hanging portion 60a of the pressing plate 60 face each other with a slight space therebetween. The punch 52 can be reliably driven by the eccentric cam 54 via the cam holder 56, and the reliability of the punching operation on the sheet material can be greatly improved.

[0004]

However, the above-mentioned sheet-shaped punch has the following problems. Processing the cam holder 56 into a horizontal D-shape using a metal plate material is time-consuming because the shape is complicated. Further, when the cam holder 56 is newly provided with the holding plate 60, the number of parts increases and the number of mounting operations also increases, so that there is a problem that the product cost increases. Also, the punch guide 58
Must be formed into a non-circular shape that is difficult to process,
There is also a problem that it takes time.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to solve the above-mentioned problems, and it is an object of the present invention to restrict the rotation of a punch without using a cam holder or a holding plate and keeping the outer shape of a punch guide circular. It is another object of the present invention to provide a sheet-like punching device capable of pushing a punch into a bunch guide by an eccentric cam and forcibly lifting the punch from the punch guide.

[0006]

In order to achieve the above object, according to the present invention, there is provided a sheet material punching apparatus according to the present invention, wherein the cylindrical member is slidably mounted on a punch guide provided on a sheet material holder. And a eccentric cam attached to a drive shaft on the head side of the punch so as to be rotatable and pushing the punch, wherein the outer peripheral surface of the punch head is a punch. A pair of engaging pins projecting toward both sides of the punch are provided on the flattened punch head at right angles to the axis of the punch, and the eccentric cam is A pair of large-diameter portions are formed at both ends of the cylindrical body at intervals slightly larger than the thickness of the flattened punch head, and a ring-shaped portion is formed on each of the opposing surfaces of the pair of large-diameter portions. A concave groove is formed, and the punch is Part enters between the pair of large-diameter portions, and the pair of engagement pins slidably enter the concave grooves of the pair of large-diameter portions and are integrally connected to the eccentric cam, thereby forming a punch. When pushed in the punch guide direction, the upper surface of the head comes into contact with the cylindrical body, and when the punch is pulled out from the punch guide, the engaging pin comes into contact with the inner peripheral surface of the concave groove. I do.

According to a second aspect of the present invention, there is provided a sheet punching device, wherein the punch is slidably mounted on a punch guide provided on a sheet holder, and is driven toward the head of the punch. A sheet material punching device having an eccentric cam attached to a shaft and rotatably disposed to push a punch, wherein an outer peripheral surface of a head of the punch is flattened from both sides toward an axis of the punch, and A pair of engaging pins projecting toward both sides of the punch are provided at the head of the flattened punch at right angles to the axis of the punch, and the eccentric cam is provided at both ends of the cylindrical body with the flattened punch. A pair of large-diameter portions are formed at intervals slightly wider than the thickness of the head portion, and an opening width is slightly larger than the diameter of the engagement pin on each of opposing surfaces of the pair of large-diameter portions. A concave groove is formed, and the punch is The writing head enters between the pair of large-diameter portions, and the pair of engaging pins slidably enter the concave grooves of the pair of large-diameter portions and are integrally connected to the eccentric cam, The punch is pushed in the direction of the punch guide when the engagement pin comes into contact with the concave groove, and is pulled out from the punch guide.

In these inventions, since the punch and the eccentric cam are connected by the engagement pin attached to the punch entering the concave groove provided in the eccentric cam, the punch guide is formed by the eccentric cam without using a cam holder. The punch pushed into the inside can be pulled up from the punch guide. Also,
Since the flattened punch head is sandwiched between a pair of large diameter portions provided on the eccentric cam, even if the punch tries to rotate, the punch head interferes with the inner surface of the large diameter portion and the punch Rotation is restricted. Therefore, there is no need to use a holding plate as in the related art.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a sheet material punching device according to the present invention will be described below in detail with reference to the accompanying drawings. (First Embodiment) First, a basic configuration of a sheet material punching device (hereinafter, also simply referred to as “punching device”) 10 will be described with reference to FIGS. 1 and 2. The same components as those in the conventional example are denoted by the same reference numerals, and the detailed description is omitted. As an example, the sheet material holder 12 is provided with a gap 14 between two surfaces of two L-shaped metal plate materials 12a and 12b.
The sheet material (not shown) passes through the gap 14. Further, a cylindrical punch guide 16 facing the gap 14 is provided on the upper metal plate 12a. On the other hand, a through-hole (perforation for perforation) 18 is formed in the lower metal plate 12 b at a position corresponding to the punch guide 16. Also, the sheet material holder 12
Is provided with a feed roller 20, and the sheet material is fed into the gap 14 by the feed roller 20 to be perforated.
It is then discharged.

The punch 52 has a cylindrical outer shape and has a punch guide 16 provided on the sheet material holder 12.
Is slidably mounted on. Accordingly, when no upward external force is applied to the punch 52, the punch 52 falls into the bunch guide 16 by its own weight. The outer peripheral surface of the head of the punch 52 is flattened from both sides toward the axis of the punch 52.
The pair of engaging pins 22 protruding toward both sides of the punch 5
2 at right angles to the axis. In detail, punch 5
The columnar engagement pins 22 are respectively provided on the flattened portions 52a formed on the heads of the second and second projections so that the axes of the engagement pins 22 are on the same straight line. The flattening section 52a
In the present embodiment, are formed by planes parallel to each other as an example, but are not necessarily formed in a plane, and may be formed by an arc having a diameter larger than a circle forming the outer periphery of the engagement pin 22, or It is sufficient that the cross-sectional shape is a non-circular figure that is a point-symmetrical figure centered on the axis, such as an elliptical cross-section.

The eccentric cam 30 is attached to the drive shaft 50 on the head side of the punch 52 (in the present embodiment, for example, above the head) and is rotatably disposed. And the drive shaft 50
When is rotated, it rotates with it, pushing the punch 52 into the punch guide 16 on the cam surface, and pulling up the punch 52 from inside the punch guide 16. In addition,
The eccentric cam 30 has a circular cross section, but functions as an eccentric cam when the drive shaft 50 is mounted at an eccentric position. Further, a detailed structure of the eccentric cam 30 will be described with reference to FIG. Eccentric cam 3
0 is an insertion hole 2 for inserting the drive shaft 50 into the eccentric position.
A pair of large-diameter portions 26 formed at both ends of the cylindrical body 24 at intervals L2 slightly wider than the thickness L1 of the flattened head of the punch 52; And a ring-shaped concave groove 28 formed so that each opening portion is opposed to each opposing surface 26a of the large diameter portion 26. In the present embodiment, the opening width L3 of the concave groove 28 is
The eccentric cam 30 is formed to be wider than the diameter of the engaging pin 22 so that when the engaging pin 22 is inserted into the concave groove 28 as described later.
Has sufficient play to move in the radial direction.

Next, a connection structure between the punch 52 and the eccentric cam 30 will be described. The punch 52 has its head inserted between the pair of large-diameter portions 26 such that the flattened portions 52a face the large-diameter portions 26, and each of the engagement pins 22 projecting from each flattened portion 52a has a pair. Slidably enters the concave groove 28 of the large diameter portion 26. As a result, even if the punch 52 attempts to rotate about the axis, the punch 52 does not rotate because the flattened portion 52a formed on the head interferes with the opposing surface of the large-diameter portion 26. The mating pin 22 does not fall out of the concave groove 28 and is integrally connected to the eccentric cam 30. However, the distance L between the opposing surfaces 26a of the pair of large diameter portions 26
2 is slightly larger than the thickness L1 of the head of the punch 52, and the opening width L3 of the concave groove 28 is larger than the diameter of the engaging pin 22, so that the punch 52 can move along the outer periphery of the eccentric cam 30. It is possible. When the punch 52 is attached to the eccentric cam 30, as shown in FIG. 8, one of the large-diameter portions 26 (the right side in the figure) has an outer periphery at one end of the cylindrical body 24. A disk 27 is detachably attached to the other end face (left side in the figure) of the cylindrical body 24 and is attached to the other end face of the cylindrical body 24, so that the other large-diameter portion 26 is formed. Since the structure is formed at the other end of the cylindrical body 24, the head of the punch 52 is brought close to the cylindrical body 24 in a state where the disk body 27 is detached from the cylindrical body 24, and the engaging pin 22 is formed. One of the large diameter portions 26
And then insert the disc body 27 into the cylindrical body 24.
The other large diameter portion 26 formed between the other large diameter portion 26 and the cylindrical body 24 while attaching the remaining engagement pin 22 to the other large diameter portion 26.
May be inserted into the concave groove 28.

Next, an outline of the operation of the sheet material punching apparatus 10 will be described with reference to FIGS. First, the eccentric cam 30 is at the position shown in FIG. 1, and the punch 52 is stopped at the top dead center. Therefore, the lower end of the punch 52 is in a state where it does not protrude downward from the upper metal plate 12a. In this case, as shown in FIG. 2, the lower part of the engaging pin 22 provided on the head of the punch 52 abuts on the outer peripheral surface 28 a of each groove 28 provided on each large diameter portion 26. And is held so as not to fall into the punch guide 16. next,
A sheet material (not shown) is fed into the gap 14 between the pair of metal plate materials 12a and 12b by the feed roller 20, and stops when a portion to be pierced reaches the perforation hole 18.

Next, the drive shaft 50 is driven by one rotation by, for example, an electric motor (not shown). This drive shaft 50
As the eccentric cam 30 makes one rotation, the punch 52 moves up and down in the order of top dead center → bottom dead center → top dead center, and when the lower end of the punch 52 enters the perforation hole 18, The sheet material is perforated in combination with the perforation holes 18.

When the eccentric cam 30 rotates, the punch 52
Will be described for each rotation angle of the eccentric cam 30 from the initial position (standby position). FIG. 1 shows the initial position. As described above, the punch 52 is directly held by the eccentric cam 30 and located at the top dead center. FIG. 3 shows a state when the camera is rotated by about 45 degrees from the initial position. The contact portion of the concave groove 28 of the eccentric cam 30 with the engaging pin 22 provided on the punch 52 gradually starts to tilt as the eccentric cam 30 rotates, and the engaging pin 22 moves the outer peripheral surface 28a of the inclined concave groove 28. The punch 52 slides and moves in the concave groove 28, and accordingly, the punch 52 gradually starts falling in the punch guide 16. The head of the punch 52 has not yet contacted the outer peripheral surface of the cylindrical body 24 of the eccentric cam 30. In this embodiment, the outer peripheral surface of the cylindrical body 24 has the same diameter as the inner peripheral surface 28b of the concave groove 28 as an example, and is continuous. Therefore, the outer peripheral surface of the cylindrical body 24 may be indicated by reference numeral 28b.

FIG. 4 shows a state when the camera is rotated by about 90 degrees from the initial position. The lower end of the punch 52 is the upper metal plate 12a.
After a while, the free fall of the punch 52 is limited by the contact of the tip of the punch 52 with the sheet material, and the engaging pin 22 floats from the outer peripheral surface 28a of the groove 28. In this state, the head of the punch 52 has begun to come into contact with the outer peripheral surface 28 b of the cylindrical body 24 of the eccentric cam 30, and the punch 52 begins to be forcibly pushed into the punch guide 16 by the cylindrical body 24. FIG. 5 shows a state when the camera is rotated by about 180 degrees from the initial position. The punch 52 is further pushed into the punch guide 16 by the cylindrical body 24 of the eccentric cam 30, and reaches the bottom dead center. In this case, punch 5
Since the lower end of 2 enters the perforation hole 18, the sheet material is perforated by the combination of the lower end of the punch 52 and the perforation hole 18. After punching, the head of the punch 52 is in contact with the outer peripheral surface 28b of the cylindrical body 24 as shown in FIG. Although the inner diameter of the perforation hole 18 is slightly larger than the inner diameter of the perforation hole 18, the outer diameter of the lower end of the punch 52 and the perforation hole 18 Some parts are always in contact with the inner circumference like scissors,
The punch 52 does not fall freely due to the friction of the contact portion.

FIG. 7 shows a state in which it has been rotated about 270 degrees from the initial position. In this state, the engaging pin 22 has begun to come into contact with the outer peripheral surface 28a of the concave groove 28 of the eccentric cam 30 again, and as the eccentric cam 30 rotates, the engaging pin 22 slides in the concave groove 28 and moves upward. Move to. As a result, the punch 52 begins to be forcibly pulled out of the punch guide 16. Thereafter, the eccentric cam 30 returns to the initial position shown in FIG. 1 again, and accordingly, the punch 52 also returns to the top dead center. At that point, the rotation of the drive shaft 50 stops and the punching operation on the sheet material is completed. After the punching operation is completed, the feed roller 20 rotates to divide the sheet material into a pair of metal plate materials 12.
The gas is discharged from the gap 14 between the holes a and 12b.

As described above, with the rotation of the eccentric cam 30, the punch 52 moves up and down in the punch guide 16, but the head of the punch 52 is flattened between the pair of large diameter portions 26 of the eccentric cam 30. When the portion moves, the interval L2 between the large diameter portions 26 is formed only slightly wider than the thickness L1 between the flattened portions 52a of the head, so even if the punch 52 tries to rotate. The flattening portion 52a of the head does not rotate because it interferes with the inner surface of the large diameter portion 26.

(Second Embodiment) First, FIG. 9 and FIG.
The basic configuration of the sheet material punching device (hereinafter, also simply referred to as “punching device”) 32 will be described with reference to FIG. Since the basic structure is the same as that of the first embodiment, the same components are denoted by the same reference numerals, and detailed description is omitted. The punching device 32 includes a sheet material holder 12 having metal plate materials 12a and 12b, a punch 52 mounted on a punch guide 16 provided on the upper metal plate material 12a, and an eccentric cam that is mounted on a drive shaft 50 and rotates. 34.

The difference from the first embodiment is the structure of the eccentric cam 34, and the structure will be described. The eccentric cam 34 is basically the same as the eccentric cam 30 of the first embodiment, except that the facing surface 26
The position of the concave groove 28 formed in a is slightly different. In detail, as shown in FIG. 10, the eccentric cam 34 includes a cylindrical body 24 having an insertion hole 24a for inserting the drive shaft 50 at an eccentric position, and a punch 52 flattened at both ends of the cylindrical body 24. A pair of large-diameter portions 26 formed with an interval L2 slightly wider than the thickness L1 of the head portion, and a pair of large-diameter portions 26 are formed so that their respective openings face the respective opposing surfaces 26a. And a ring-shaped groove 28. In the present embodiment, the opening width L3 of the concave groove 28 is formed to be slightly wider than the diameter of the engaging pin 22. Groove 2 of pin 22
The play in which the eccentric cam 30 can move in the radial direction in the groove 8 is extremely smaller than that in the first embodiment within a range in which the engagement pin 22 can maintain a state in which the engagement pin 22 can slide freely in the groove 28. ing. The same applies to the first embodiment, but the tip of each engagement pin 22 does not contact the inner bottom surface of each groove 28. This is to reduce friction as much as possible and to smoothly move the engagement pin 22 in the concave groove 28.

Further, as shown in FIG. 16, a concave groove 28 formed in the facing surface 26a of each large diameter portion 26 has an inner peripheral surface 2a.
The diameter L4 of 8b is set to be larger than the outer diameter L5 of the cylindrical body 24. Accordingly, a gap Z formed between the opposing surface 26a on the inner diameter side of the concave groove 28 of each large diameter portion 26 and the outer peripheral surface of the cylindrical body 24 is formed on the outer peripheral surface of the cylindrical body 24, and the punch 52 When the head of the punch 52 enters between the large-diameter portions 26 and the engaging pin 22 enters the concave groove 28, the head of the punch 52 above the engaging pin 22 enters the gap Z. Interference with the eccentric cam 34 can be avoided.

Next, an outline of the operation of the sheet material punching apparatus 10 will be described with reference to FIGS. The difference from the first embodiment is that in the first embodiment, the head of the punch 52 is pushed by the outer peripheral surface of the cylindrical body 24 of the eccentric cam 30 when the sheet material is pierced. Punch guide 16
Although the groove 28 and the engagement pin 22 are engaged when pulling out from the groove, the groove 2 is always used in the present embodiment.
8 has an inner peripheral surface 28b or an outer peripheral surface 28a
Punch 52 that has entered gap Z
Does not come into contact with the outer peripheral surface of the cylindrical body 24. Therefore, the point is that the inner peripheral surface of the concave groove 28 is also performed by pushing the engaging pin 22 downward during the drilling operation.

First, the eccentric cam 34 is at the position shown in FIG. 9, and the punch 52 stops at the top dead center. Therefore, the lower end of the punch 52 is in a state where it does not protrude downward from the upper metal plate 12a. In this case, as shown in FIG. 10, the lower part of the engaging pin 22 provided on the head of the punch 52 is in contact with the outer peripheral surface 28a of the ring-shaped groove 28. It is held so that it does not fall inside. Next, a sheet material (not shown) is fed into the gap 14 between the pair of metal plate materials 12a and 12b by the feed roller 20, and stops when a portion to be pierced reaches the perforation hole 18.

Next, the drive shaft 50 is driven by one rotation, for example, by an electric motor (not shown). This drive shaft 50
With the rotation of, the eccentric cam 34 also makes one rotation, and the punch 52 moves up and down in the order of top dead center → bottom dead center → top dead center, and when the lower end of the punch 52 enters the perforated through hole 18, The sheet material is perforated in combination with the perforation holes 18.

When the eccentric cam 34 rotates, the punch 52
Will be described for each rotation angle of the eccentric cam 34 from the initial position (standby position). In the initial position as shown in FIGS. 9 and 10, the punch 52 is directly held by the eccentric cam 34 and located at the top dead center, as described above. FIG. 11 shows a state when the camera is rotated by about 45 degrees from the initial position. Eccentric cam 3
When the eccentric cam 30 rotates, the contact portion of the concave groove 28 with the engaging pin 22 provided on the punch 52 starts to gradually tilt, and the engaging pin 22 slides on the outer peripheral surface 28 a of the inclined concave groove 28. It moves in the concave groove 28, and the punch 52
Gradually begins to fall in the punch guide 16.

FIG. 12 shows a state when the camera is rotated by about 90 degrees from the initial position. The lower end of the punch 52 is the upper metal plate 12.
a, and after a while, the punch 52
Is restricted by the tip of the punch 52 abutting on the sheet material. In this state, the engaging pin 22 starts to contact the inner peripheral surface 28b of the concave groove 28, and the punch 52 is Accordingly, the inner peripheral surface 28b of the concave groove 28 starts to be forcibly pushed into the punch guide 16. FIG. 13 shows a state when the camera is rotated by about 180 degrees from the initial position. Punch 52
Is further pushed into the punch guide 16 by the inner peripheral surface 28b of the concave groove 28 of the eccentric cam 30, and reaches the bottom dead center.
At this time, since the lower end of the punch 52 enters the perforation hole 18, the sheet material is placed between the lower end of the punch 52 and the perforation hole 1.
8 are perforated in combination. Eccentric cam 34 in this state
FIG. The head of the punch 52 enters the gap Z, and the upper surface of the head is
Is not in contact with the outer peripheral surface.

FIG. 15 shows a state in which it has been rotated about 270 degrees from the initial position. In this state, the engaging pin 22 has begun to come into contact with the outer peripheral surface 28a of the concave groove 28 of the eccentric cam 34 again, and when the eccentric cam 34 rotates, the engaging pin 22 slides inside the concave groove 28 while sliding upward. Move to. As a result, the punch 52 begins to be forcibly pulled out of the punch guide 16. Thereafter, the eccentric cam 34 returns to the initial position shown in FIG. 1 again, and the punch 52 also returns to the top dead center accordingly, at which point the rotation of the drive shaft 50 stops and the punching operation on the sheet material is completed. After the punching operation is completed, the feed roller 20 rotates to divide the sheet material into a pair of metal plate materials 12.
The gas is discharged from the gap 14 between the holes a and 12b. In addition, the rotation of the punch 52 during the above-described punching operation is prevented by the same operation as in the first embodiment.

In the present embodiment, the concave groove 2 provided on the eccentric cam 34 and into which the engaging pin 22 of the punch 52 enters.
8 is configured so as to be as narrow as possible within a range in which the engaging pin 22 can move smoothly in the concave groove 28, so that the eccentric cam 3 in the concave groove 28 of the engaging pin 22 is formed.
The movement of 4 in the radial direction is extremely small. In addition, the eccentric cam 3
4 does not come into contact with the upper surface of the head of the punch 52. Therefore,
The eccentric cam 34 reduces unevenness in the reciprocating motion of the punch.
And the driving noise of the punch 52 is good when the conventional cam holder 56 is used or the eccentricity of the engaging pin 22 in the concave groove 28 as in the first embodiment. There is an effect that the cam 30 is largely moved in the radial direction, and is extremely lower during the pushing operation than when the head of the punch 52 contacts the eccentric cam 30.

In each of the above embodiments, the eccentric cams 30 and 34 are, as shown in FIG. 8 and FIG.
One large diameter portion 26 is integrated with the outer periphery of one end (right end in each figure) of the cylindrical body 24, and the other large diameter portion 26 is
7 is attached to the other end surface of the cylindrical body 24 (the left surface in each figure), so that the disk body 27 is formed at the other end of the disk body 27. In the method of attaching to the end face of the cylindrical body 24, a structure in which the fixing is performed by using the screw 36 is adopted. However, as shown in FIG. Tongue piece 3 having a hook-shaped tip
8 is projected, the engaging tongue 38 is inserted into a hole 27a provided in the disc body 27, and the edge of the hole 27a and the tip of the engaging tongue 38 are engaged to be integrated. Is also good.
With this structure, the number of screws 36 can be reduced and screwing work can be eliminated, so that product cost can be reduced.

In the above embodiment, the punch 5
Reference numeral 2 denotes a structure which moves up and down along the punch guide 16 and pierces the sheet material when it moves downward. Since the head 24 is moved forward and backward by being pushed by the body 24, the direction of forward and backward movement is not limited to the vertical direction, but may be horizontal or oblique. Also, in the vertical direction, the configuration shown in FIG. 1 is turned upside down, and the punch 52 is positioned below the perforation hole 18, and perforates the sheet material together with the perforation hole 18 when moving upward. Is also possible.

In the above-described embodiment, the punch 5
The eccentric cam 3 has a head that enters between the large-diameter portions 26 and the engaging pin 22 slidably enters a concave groove 28 of the large-diameter portion 26.
0, 34, the punch 5
The punch 52 is formed in a cylindrical shape, and the inner peripheral surface of the bunch guide 16 is formed in a cylindrical shape in order to explain that the rotation of the punch 52 can be restricted even when the punch 2 is formed in a cylindrical shape. However, even if the punch 52 is formed to have a non-circular cross-section such as an ellipse or polygon, and does not rotate in the punch guide 16 due to the outer shape of the punch 52 itself, the cam holder is not required. Also, the punch 52 can be pulled out from the punch guide 16 and the structure can be simplified. In the second embodiment, the reciprocation of the punch 52 has less unevenness, so the followability of the punch 52 to the rotation of the eccentric cam 34 is good, and the driving sound of the punch 52 is a case where a conventional cam holder is used. The effect of being very low as compared with that of the conventional sheet punching device is naturally exerted.

Although the preferred embodiments of the present invention have been described in various ways, the present invention is not limited to the above-described embodiments, and many modifications can be made without departing from the spirit of the invention. Of course.

[0033]

According to the sheet punching device of the present invention, the punch and the eccentric cam are connected by the engagement pin attached to the punch entering the concave groove provided in the eccentric cam. The punch pushed into the punch guide by the eccentric cam without using the cam holder can be pulled up from the punch guide. Further, since the head of the flattened punch is sandwiched between a pair of large diameter portions provided on the eccentric cam, even if the punch tries to rotate, the head of the punch interferes with the inner surface of the large diameter portion. The rotation of the punch is restricted. Therefore,
There is no need to use a holding plate as in the prior art. Therefore, there is an effect that the number of parts can be reduced and the product cost can be reduced. Furthermore, in the sheet material punching device according to the second aspect, since the reciprocating motion of the punch has less unevenness, the followability of the punch to the rotation of the eccentric cam is good, and the driving sound of the punch is smaller than that in the case of using the conventional cam holder. Has the effect of being very low.

[Brief description of the drawings]

FIG. 1 is a side view showing a configuration of a first embodiment of a sheet material punching device according to the present invention.

FIG. 2 is a cross-sectional view taken along a driving axis direction in FIG.

FIG. 3 is an explanatory diagram showing a state in which the eccentric cam of FIG. 1 is rotated by about 45 degrees from an initial position.

FIG. 4 is an explanatory view showing a state in which the eccentric cam of FIG. 1 is rotated by about 90 degrees from an initial position.

FIG. 5 is an explanatory diagram showing a state in which the eccentric cam of FIG. 1 has rotated about 180 degrees from an initial position and a punch has reached a bottom dead center.

FIG. 6 is a sectional view taken along the direction of the drive shaft in FIG. 5;

FIG. 7 is an explanatory diagram showing a state in which the eccentric cam of FIG. 1 has been rotated about 270 degrees from an initial position.

FIG. 8 is an exploded sectional view showing the structure of the eccentric cam of FIG.

FIG. 9 is a side view showing the configuration of a second embodiment of a sheet material punching device according to the present invention.

FIG. 10 is a cross-sectional view along the drive axis direction of FIG.

FIG. 11 is an explanatory view showing a state in which the eccentric cam of FIG. 9 is rotated by about 45 degrees from an initial position.

FIG. 12 is an explanatory view showing a state where the eccentric cam of FIG. 9 is rotated by about 90 degrees from an initial position.

FIG. 13 is an explanatory diagram showing a state in which the eccentric cam of FIG. 9 has rotated about 180 degrees from an initial position, and the punch has reached a bottom dead center.

FIG. 14 is a sectional view taken along the direction of the drive shaft in FIG.

FIG. 15 is an explanatory diagram showing a state where the eccentric cam of FIG. 9 is rotated by about 270 degrees from an initial position.

FIG. 16 is an exploded sectional view showing the structure of the eccentric cam of FIG. 9;

FIG. 17 is a sectional view showing another assembly structure of the eccentric cam.

FIG. 18 is a perspective view showing a configuration of an example of a conventional sheet material punching device.

[Explanation of symbols]

 Reference Signs List 10 sheet material punching device 12 sheet material holder 16 punch guide 22 engaging pin 26 large diameter portion 28 concave groove 30 eccentric cam 50 drive shaft 52 punch 52a flattening portion

Claims (2)

[Claims] 1. A cylindrical punch slidably mounted on a punch guide provided on a sheet material holder, and a punch mounted on a drive shaft on the head side of the punch so as to rotate freely. A punching machine having a moving eccentric cam, wherein the outer peripheral surface of the punch head is flattened from both sides toward the axis of the punch, and the flattened punch head has both sides of the punch. A pair of engaging pins projecting toward the punch are provided at right angles to the axis of the punch, and the eccentric cams are provided at both ends of the cylindrical body at a slightly wider interval than the thickness of the flattened punch head. A large-diameter portion is formed, and a ring-shaped concave groove is formed on each of the opposing surfaces of the pair of large-diameter portions. In the punch, the head enters between the pair of large-diameter portions. The pair of engagement pins are When the punch is slidably inserted into the groove and integrally connected with the eccentric cam, and the punch is pushed in the punch guide direction, the upper surface of the head comes into contact with the cylindrical body, and the punch is moved from the punch guide. A sheet material punching device wherein the engaging pin comes into contact with the inner peripheral surface of the concave groove when being pulled out. 2. A cylindrical punch slidably mounted on a punch guide provided on a sheet material holder, and a punch mounted on a drive shaft on a head side of the punch so as to be rotatable and press the punch. A punching machine having a moving eccentric cam, wherein the outer peripheral surface of the punch head is flattened from both sides toward the axis of the punch, and the flattened punch head has both sides of the punch. A pair of engaging pins projecting toward the punch are provided at right angles to the axis of the punch, and the eccentric cams are provided at both ends of the cylindrical body at a slightly wider interval than the thickness of the flattened punch head. And a ring-shaped groove having an opening width slightly larger than the diameter of the engagement pin is formed on each of the opposing surfaces of the pair of large-diameter portions. Part enters between the pair of large diameter parts and The pair of engaging pins slidably enter the concave grooves of the pair of large-diameter portions and are integrally connected to the eccentric cam. The punch is formed by bringing the engaging pins into contact with the concave grooves. A sheet material punching device which is pushed in a guide direction and is pulled out from a punch guide.