JPH06328396A - Punching blade - Google Patents

Abstract

PURPOSE:To abolish or to lighten levelling work in a punching machine to punch a sheet type work. CONSTITUTION:A large number of holes 4 are provided between a blade edge part 2 formed on one edge of a band plate type blade main body 1 and an upper edge part 3 on the opposite side of the blade edge part 2, and by devising the blade edge part 2 to have a cushioning property in the punching direction at the time when pushing-down force is added to the upper edge part 3, the blade edge part 2 is made to make contact with a work uniformly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a punching blade (Thomson blade) used in a punching machine for punching a sheet-like work such as thick paper.

[0002]

2. Description of the Related Art Conventionally, in a punching machine of this type, as shown in FIG.
A strip-shaped punching blade 12 is fitted and held in a slit 11 formed in 0, and an upper platen 13 of the punching machine is held.
The work W, the wooden mold 10, the thin metal plate 15, and the thick paper 16 are arranged in this order between the lower platen 14 and the lower platen 14, and the work W is punched by compressing these. In the figure, 17 is a sponge-like elastic body for pressing the work W,
Reference numeral 18 denotes a push blade for making a crease on the work W.
At this time, the parallelism and flatness of the upper and lower platens 13 and 14 are not obtained, the accuracy of the wooden mold 10 is poor, and the cutting load is nonuniform (for example, the cutting lines are concentrated and some are small). If there is such a situation, the punching blade 12 is in a one-sided contact state, and a part that cannot be cut is partially formed in the work W. In order to eliminate this defective cutting, the punching blade 12
The work of adjusting the contact condition of the blade edge 12a (commonly called “unevenness removal”) is repeated several times. In this unevenness removing work, the height of the work W is adjusted by trial-punching the work W and checking for defective cutting parts, and then sticking a narrow adhesive paper tape (not shown) on the thick paper 16 in correspondence with the uncut parts. Usually, one paper tape is about 0.05 mm in the drive, and when it is insufficient, the paper tape is pasted.

[0003]

[Problems to be Solved by the Invention] In recent years, demand for high-mix low-volume production has increased in the market. Therefore, there is an increasing demand for quick setup work when changing the die of a punching machine. Since the unevenness removal work described above requires considerable experience and dexterity, it takes a long time for a skilled worker to work with the actual product, but this is a bottleneck for improving productivity. ing. In addition, it is becoming difficult to secure skilled workers every year. The upper platen 1
It is conceivable to interpose a hard rubber plate between 3 and the wooden mold 10 to absorb the dimensional error of each part, but it is not effective for removing unevenness in a wide range, and there is a problem in durability, and it is put to practical use. Is difficult.

Therefore, the present invention aims to eliminate or reduce the unevenness removing work in the punching machine as a technical problem to be solved.

[0005]

[Means for Solving the Problems] In order to solve the above problems, the following punching blade was created. That is, the present invention is a punching blade of a punching machine for punching a sheet-like work, a blade tip portion formed on one edge of a strip plate-shaped blade body, and an upper edge portion opposite to the blade tip portion. In between, a hole is provided in the cutting edge portion to provide cushioning properties in the punching direction when a pressing force is applied to the upper edge portion.

[0006]

By forming a hole in the strip plate-shaped blade body of the punching blade, cushioning in the punching direction is imparted to the blade tip portion. When a work is punched with this punching blade, at the place where the work is cut quickly, the cutting edge part contacts the lower platen of the punching machine and bends upward by the cushion allowance, so the cutting edge is almost uniform over the entire length of the punching blade. It is possible to contact the lower platen, and it is possible to punch out the work without making uncut parts.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the punching blade is a strip-shaped blade body 1
(For example, a plate thickness of 0.7 mm and a width of 23.6 mm), elongated oblong holes 4 to 4 are provided at predetermined intervals in the longitudinal direction between the blade edge portion 2 formed at the lower edge and the upper edge portion 3 of the blade body 1. It is formed by. In the above-mentioned conventional example, since the paper tape application is usually repeated several times, the adjustment allowance is estimated to be 0.1 mm to 0.2 mm,
The shape and number of the holes 4 are set so that the blade main body 1 has a predetermined cushioning allowance and a spring constant corresponding thereto in the width direction.

FIG. 2 shows an example of a Thomson wooden mold in which the above punching blade is implanted. In the figure, 10 is a flat wooden type,
17 is a sponge-like elastic body (however, only a part is shown), 1
8 is a pushing blade. The manner of punching the work W such as cardboard with the punch 10 equipped with the wooden mold 10 in which the blade body 1 is fitted is the same as in the conventional example, and therefore the description thereof is omitted. In addition, FIG.
If the punching blade 12 is replaced with that of this embodiment in
This figure corresponds to the XX section of FIG.

Next, the mechanism when the work W is compressed and cut by the punching machine will be described. FIG. 3 shows the relationship between the stroke S of the punching blade and the compression pressure P, and also schematically shows the positions of the punching blade corresponding to points A, B and C in the figure. In the same drawing, the upper platen 13 of the punching machine starts descending from the state of being at the top dead center A, and at the point B, the cutting edge portion 2 of the punching blade punches the work W and contacts the lower platen 14 of the punching machine. At this stage, the work W is usually left uncut. Then, a pressing force is further applied to the upper platen 13, the upper edge portion 3 of the punching blade is displaced so as to approach the cutting edge portion 2, and the upper platen 13 descends. This cushion stroke is represented by δ in the figure. In other words, since the blade tip 2 can bend in the punching direction, the blade tip 2 comes into contact with the lower platen 14 almost uniformly over the entire length of the punching blade, and the cutting of the work W is completed at the point C.

In the conventional punching blade, when the cutting edge is in a one-sided contact state, the compression pressure P of the punching blade is locally excessive as shown by the broken line in FIG. 3, causing the blade spillage. Moreover, the work W is left uncut. On the other hand, in the present embodiment, the dimensional error of each part can be absorbed by the cushion trouser δ, so that the cutting edge part 2 can uniformly contact the work W and cut it.

The shape of the hole 4 provided in the blade main body 1 is as shown in FIGS. 4A and 4B, and the "V" shaped portion 5 connects between the blade tip portion 2 and the edge portion 3. In addition to
An appropriate shape such as a square or a circle can be selected. Also,
You may form these holes 4 in multiple stages side by side.

[0012]

As described above, in the punching blade of the present invention, the cutting edge is provided with cushioning property in the punching direction, and the cushioning allowance causes dimensional error of the punching machine and uneven cutting load. Is absorbed, and the work can be punched out without making uncut parts. Further, since the local excessive pressure is not applied to the cutting edge of the punching blade, the durability of the punching blade is improved. Therefore, it is possible to eliminate or reduce the unevenness removing work in the conventional punching machine, and it is possible to quickly perform the setup work at the time of changing the die of the punching machine, so that it is possible to improve the productivity of the punching work. is there.

[Brief description of drawings]

FIG. 1 is a perspective view of a punching blade according to an embodiment.

FIG. 2 is a front view showing a wooden mold in which the punching blade of the embodiment is implanted.

FIG. 3 is a diagram showing a relationship between a stroke of a punching blade and a compression pressure when punching a work W with the punching blade of the embodiment.

FIG. 4 is a diagram showing another example of a punching blade.

FIG. 5 is a cross-sectional view schematically showing a main part of a punching machine.

[Explanation of symbols]

 1 Blade Main Body 2 Blade Edge 3 Upper Edge 4 Hole W Work

Claims (1)

[Claims] 1. A punching blade of a punching machine for punching a sheet-like work, which is between a cutting edge portion formed on one edge of a strip plate-shaped blade body and an upper edge portion opposite to the cutting edge portion. A punching blade having a hole for cushioning the punching direction when a pressing force is applied to the upper edge.