JPH0651280B2 - Blade pressure controller for punching machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a device for controlling the blade pressure of a cutting blade in a machine for punching a sheet material such as paper into a required shape.

[Prior art and its problems]

For example, in order to make a paper box, when punching out a sheet of paper in the expanded shape of the paper box, a punching machine as shown in FIG. 8 is usually used. In the figure, 11 is a cutting edge formed in a punched shape,
The cutting edge 11 is supported by a wooden cutting edge support panel 12. The cutting blade 11 penetrates the cutting blade support panel 12 in the plate thickness direction, and is attached so that its back surface is exposed on the back surface of the cutting blade support panel 12. The cutting blade support panel 12 is held on the chase 15 by the tightening plate 13 and the push screw 14, and in that state,
Upper surface plate of the press machine via the unevenness removing plate 16 and the holding plate 17.
Mounted on 18.

Further, 21 is a metal hard face plate on which the paper 20 is placed, and this face plate 21 is attached to a lower surface plate 23 of the pressing device via a face plate receiver 22 made of metal or hard resin. Incidentally, 24 is a gripper bar for grasping the paper 20, and 25 is a rubber member for extracting the punched paper from the cutting blade 11.

Since this type of punching machine punches by pressing the cutting edge 11 against the paper 20 placed on the hard face plate 21, the cutting edge 11
If the blade edge is not adjusted so as to bite into the paper 20 evenly over the entire circumference, there will be partially cut portions and uncut portions (unevenness in cutting conditions), and complete punching cannot be performed.

For this reason, in this type of punching machine, it is necessary to perform "unevenness removal" before starting the punching work. This work is to adjust the cutting condition of the cutting blade to be even in each part, and is performed as follows. First, make a trial cut, inspect the cutting condition over the entire circumference, and if there is a part that is not sufficiently cut, remove the cutting blade support panel 12 together with the chase 15 from the upper surface plate 18 and check the cutting condition of the unevenness removing plate 16. Stick a piece of paper or cellophane tape, etc. on the position corresponding to the bad part (this is called patchwork). After that, the cutting blade support panel 12 is attached to the upper surface plate 18 again and trial cutting is performed. If paper or cellophane tape, etc. is interposed between the unevenness removing plate 16 and the pressing plate 17 as described above, the cutting edge will be strongly pressed by the thickness when punching. Will be improved. If there are still some parts that cannot be cut even after this trial cutting, adjust the patchwork again.

After performing the unevenness removing work in this way, the original punching work is started, but since this unevenness removing work is performed manually, it is not only time-consuming and costly, but also requires considerable skill. There is.

Also, even if the unevenness is removed and then the punching work is started, if the number of punches increases, unevenness in the cutting may occur from the middle.In that case, the machine must be stopped to remove the unevenness. Disappear. Therefore, there is a problem that the operating rate of the machine is reduced.

[Means for solving problems and their effects]

An object of the present invention is to provide a blade pressure control device for a punching machine in which the unevenness removing work can be omitted in view of the problems of the conventional techniques as described above.

For this reason, the present invention is a punching machine in which a cutting edge supported by a cutting edge support panel in a punching shape is pressed against a sheet material such as paper set on a hard face plate to punch the sheet material into a required shape. , In order to be able to control the cutting condition of each part of the cutting blade to be substantially equal, the punching is performed on the back side of the cutting blade support panel or the back surface of the face plate, or both, at a position corresponding to at least the cutting blade. A pressure sensor that sometimes detects the blade pressure applied to the cutting edge and a variable thickness element that can control the thickness of itself from the outside are arranged in a number corresponding to the top and bottom, and the blade detected by each pressure sensor It is characterized in that the thickness of the corresponding variable thickness element is controlled so that the blade pressure of each part becomes an appropriate value according to the pressure.

When the blade pressure applied to the cutting edge during punching is low, the cutting quality is poor, and when it is high, the cutting quality is good, but the cutting edge tends to be heavily worn. That is, there is an appropriate blade pressure for maintaining a good cutting condition. Therefore, the present invention detects the blade pressure of each part of the cutting blade, and when the blade pressure is not proper, the blade pressure is controlled by controlling the thickness of the thickness variable element arranged at the position corresponding to the pressure sensor. This is so that it can be adjusted to an appropriate value. That is, the present invention automatically performs the conventional patchwork using the variable thickness element.

It is preferable to use a thick electric element or a magnetostrictive paper as the variable thickness element, but it is also conceivable to use another element such as one whose thickness is adjusted by a combination of a small motor and a screw.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 and 2 show an embodiment of the present invention. This device, as shown in FIG. 1, is the back side of the cutting blade support panel 12,
That is, the lower surface of the upper surface plate 18 has the element array plate 31.
The element array plate 31 has a large number of holes opened on the lower surface arranged vertically and horizontally, and a pressure sensor 32 and a thickness variable element 33 are housed in a stacked state in each hole. Pressure sensor
Reference numeral 32 is for converting pressure into an electric signal, and a piezoelectric element is usually used. As the variable thickness element 33, a piezoelectric element whose size (thickness) changes according to an applied voltage is used here. The other configuration of FIG. 1 is the same as that of the conventional example of FIG. 8, but one or both of the unevenness removing plate 16 and the suppressing plate 17 may be omitted.

FIG. 2 is a block diagram of a circuit that controls the thickness variable element 33 according to the pressure detected by the pressure sensor 32. 34 is a peak hold circuit corresponding to each pressure sensor 32, 35 is a multiplexer for sequentially reading the value of the peak hold circuit 34, 36
Is an amplifier, 37 is an A / D converter, 38 is a computer, 39 is the top dead center detector of the lower platen 23, 40 is a D / A converter, and 41 is the voltage applied to the thickness variable element 33. It is a variable power supply.

The computer 38 performs the processing shown in FIG. First, when the control system is started, all peak hold circuits 34 are cleared in the first step. Next, it is judged in the second step whether the lower surface plate 23 has reached the top dead center by referring to the presence or absence of the signal from the top dead center detector 39. When not reaching the top dead center, repeat the second step. The time when the lower surface plate 23 reaches the top dead center is the moment of punching, and at this time, the blade pressure applied to the cutting edge 11 becomes maximum. Therefore, when the lower surface plate 23 reaches the top dead center, the peak hold circuit 34 stores the maximum value of the blade pressure of each part. If the computer 38 determines that the lower surface plate 23 has had the top dead center, to operate the multiplexer 35 at the next third step, the value D _n of blade pressure stored in the peak hold circuit 34 sequentially, amplifier 36 , Read through A / D converter 37.

An appropriate blade pressure C _{n at} each position is set in advance in the computer 38, and in the next fourth step, the difference between the set value C _n and the measured value D _n is calculated. When the measured value is larger than the set value at a certain position, that is, when the blade pressure is high, the voltage drop command corresponding to the difference is issued in the fifth step, and the D / A
The output voltage of the variable power source 41 is lowered through the converter 40, and the thickness of the thickness variable element 33 at that position is reduced accordingly. If the thickness of the variable thickness element 33 is reduced, the blade pressure will be correspondingly reduced in the next punching. When the measured value is smaller than the set value at a certain position, that is, when the blade pressure is low, a voltage increase command corresponding to the difference is issued in the sixth step, and the output of the variable power source 41 is output through the D / A converter 40. The voltage is increased, and the thickness of the thickness variable element 33 at that position is increased accordingly. As the thickness of the variable thickness element 33 becomes thicker, the blade pressure becomes higher in the next punching. Even when the measured value and the set value are the same, the sixth step is performed, but since the difference is 0, the output voltage of the variable power source 41 does not change. When the above process is completed, the process returns to the first step to prepare for the next punching.

By doing so, the blade pressure of each part is adjusted to an appropriate value every time punching is performed, so that good punching can always be performed. Of course, the process of FIG. 3 may not be performed every time, and may be performed every one of several times by counting the number of punches.

FIG. 4 shows another embodiment of the present invention. This device is a face plate
A large number of holes open to the upper surface are arranged vertically and horizontally in a face plate receiver 22 on the back surface of 21, and a pressure sensor 32 and a thickness variable element 33 are housed in a stacked state in each hole. Even in this case, the same control as in the above embodiment can be performed.

FIG. 5 shows still another embodiment of the present invention. In this device, a pressure sensor 32 is installed in a hole provided in a face plate receiver 22, and a thickness variable element 33 is installed in a hole of an element array plate 31 attached to an upper surface plate 18.
Is installed. Pressure sensor 32 and variable thickness element 33
Are arranged to face each other on a one-to-one basis. In this way, the pressure sensor and the variable thickness element can be installed separately on the upper and lower sides.

Further, in the above-described embodiment, the pressure sensor and the thickness variable element are described as being arranged on the back side of the cutting blade support panel or the back side of the face plate, or both, almost on the entire surface, but the pressure sensor and the thickness variable element are Of course, they may be arranged only at the positions corresponding to the cutting edges.

Further, although the piezoelectric element is used as the thickness variable element in the above-mentioned embodiment, the thickness variable element may be any as long as the thickness itself can be controlled from the outside. For example, as shown in FIG. 6, a male screw 51 and a female screw 52 are screwed together so that the female screw 52 does not rotate, and the male screw 51 is rotated by a small motor 53 to move up and down, or as shown in FIG. As described above, it is conceivable that the male screw 57 is screwed into the block 56 placed on the tilt table 55, and the male screw 57 is rotated by the small motor 58 to move the block 56 in the tilt direction to move it up and down. . In the case of FIG. 7, it is necessary to connect the motor shaft and the male screw with a universal joint.

〔The invention's effect〕

As described above, according to the present invention, the blade pressure of each part of the cutting blade is detected, and when the blade pressure is not proper, the blade pressure is controlled to a proper value by controlling the thickness of the thickness variable element. Since it can be adjusted, it is possible to always perform a favorable punching process without performing the unevenness removing work as in the past, which is very effective in improving the productivity of the punching process and reducing the cost.

[Brief description of drawings]

FIG. 1 is a sectional view of a punching machine portion of a blade pressure control device according to an embodiment of the present invention, FIG. 2 is a block diagram of a circuit constituting the device, and FIG. 3 is a processing content of a computer in the device. FIG. 4 is a sectional view showing another embodiment of the present invention, and FIGS. 6 and 7 are sectional views showing examples of the variable thickness element used in the present invention. FIG. 8 is a sectional view showing a conventional punching machine. 11 to cutting blade, 12 to cutting blade support panel, 18 to upper surface plate, 20 to paper, 21 to face plate, 22 to face plate receiver, 23 to lower surface plate, 31 to element array plate, 32 to pressure sensor, 33 to Variable thickness element, 34 ~ peak hold circuit, 35 ~ multiplexer, 38 ~ computer, 41 ~ variable power supply.

Claims (1)

[Claims] 1. A blade of a punching machine, wherein a cutting blade supported by a cutting blade support panel in a punched shape is pressed against a sheet material such as paper set on a hard face plate to punch the sheet material into a required shape. A pressure control device, the back side of the cutting blade support panel or the back side of the face plate, or both, at a position corresponding to at least the cutting blade, a pressure sensor for detecting the blade pressure applied to the cutting blade during punching, external From that, a large number of variable thickness elements that can control the thickness of themselves are arranged in a vertically corresponding manner, and the blade pressure of each part becomes an appropriate value according to the blade pressure detected by each pressure sensor. Thus, the blade pressure control device for a punching machine is characterized in that the thickness of the corresponding variable thickness element is controlled.