JPH11277281A - Perforation forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize an inexpensive perforating device. SOLUTION: The paper 10 on which perforation is to be formed is transported at high speed in a tense state by means of rollers 12, 14. A carbon dioxide gas laser 16 generates a laser beam continuously. A shutter disk 18 equipped with a number of fins (8 fins in this embodiment) radially is placed at a position shifted horizontally from the optical path of the laser 19 output beam, and rotated at a prescribed revolution speed by a motor 20. The output beam of the laser 16 is intermittently shielded with the fins of the shutter disk 18. The motor 20 is fixed on a holding plate 22 movable against a fixed part. With the holding plate 22, the shutter disk 18 can be adjusted in the horizontal shift quantity against the output beam of the laser 16. The horizontal shift quantity determines the cut/tie ratio of perforation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a perforation forming apparatus for forming perforations on a sheet material such as paper by a laser beam.

[0002]

2. Description of the Related Art A desired pattern can be processed with high precision by irradiating a laser beam to a workpiece with a thin beam. For example, in paper processing, there is an advantage that cuts, half cuts, and perforations can be formed in an arbitrary pattern at a high speed. The laser oscillator usually consists of a carbon dioxide laser, and makes it pulse-oscillate. Alternatively, CW oscillation is performed, and pulsed by an external modulator.

[0003]

In order to form perforations on paper conveyed at a very high speed, a laser oscillator having a correspondingly high pulse oscillation frequency and high output must be used. No.

[0004] However, the higher the output of a laser oscillator, the lower the optical response, so that the pulse frequency cannot be increased. A conventional external modulator for pulsing CW light has 100
Not only does it support up to about W, but it is very expensive. Therefore, conventionally, it has been difficult to perform low-cost and high-speed perforation processing.

An object of the present invention is to solve such a problem and to provide an inexpensive perforation apparatus which can perform high-speed perforation processing.

[0006]

A perforation processing apparatus according to the present invention comprises a laser light source and a rotation drive means, and a light-shielding portion for shielding a laser light output from the laser light source and a laser light passing therethrough. The light-transmitting portions and the light-transmitting portions are alternately arranged around the rotation axis, and the ratio of the angular width between the light-shielding portion and the light-transmitting portion on the circumference of an arbitrary radius position around the rotation axis is set at each radial position. Shutter means different in response thereto, moving means for relatively changing the distance between the optical axis of the laser light and the rotation axis of the shutter means when the laser light passes through the shutter means, It is characterized by comprising a transporting means for transporting a sheet on which a perforation is formed as a subject.

Since an optical shutter having a simple structure is used, a low-cost laser having a low optical response can be used even at a high output, and the entire apparatus can be realized at low cost.

Each of the light shielding portions has the same angular width on the circumference at an arbitrary radial position. Thereby, the rotation speed of the shutter means can be effectively reduced.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a perspective view of one embodiment of the present invention. The paper 10 on which a perforation is to be formed
The paper is conveyed at a high speed in a state of being taut by 2 and 14. The carbon dioxide gas laser 16 oscillates continuously. A shutter disk 18 having a large number (eight in this embodiment) of fins in the angular direction is placed at a position shifted laterally from the optical path of the output light of the laser 16 and rotated at a predetermined rotational speed by a motor 20. .

In this embodiment, the motor 20 is fixed to a support plate 22 which is movable with respect to a fixed portion (not shown). The support plate 22 allows the laser 16
The lateral shift amount with respect to the output light can be adjusted.

The output light of the laser 16 is intermittently shielded by the fins of the shutter disk 18. Thereby, the laser light is pulsed. Shutter disk 1
The laser pulse light passing through 8 hits the paper 10
A vertical perforation 24 is formed on the paper 10 with a cut length and a tie length corresponding to the duty ratio of the pulse light. The cut / tie ratio of the vertical perforations 24 is determined by the lateral shift amount of the shutter disk 18 with respect to the output optical axis of the laser 16.

FIG. 2 shows a front view of the shutter disk 18. The shutter disk 18 has fins 18a of equal width radially projecting therefrom, the laser light being shielded by the fins 18a, and the laser light passing through the gaps 18b between the fins 18a. Therefore, the ratio between the angle of the fin 18a and the angle of the gap 18b at a certain radial position is equal to the ratio between the tie and the cut.
Since the fins 18a have the same width, the cut ratio increases as the laser beam passes through a position shifted from the center. The actual cut length and tie length are determined by the rotation speed of the shutter disk 18 and the transport speed of the paper 10.

Although the fins 18a are arranged at equal angles in FIG. 1, they may be arranged at any angle. The pattern of perforations in a unit length is determined by the number of fins 18a, the angle at which each fin 18a is placed, and its width (corner).

Although not shown in FIG. 1, in order to prevent the laser beam reflected by the fins 18a of the shutter disk 18 from hitting unintended portions, the shutter disk 18 is concealed except for the optical axis portion of the laser beam. Housed in the case.

Even when changing the tie / cut ratio, for example, there is a case where it is desired to keep the tie length constant. In such a case, the rotation speed of the shutter disk 18 and / or the transport speed of the paper 10 may be changed.

In this embodiment, since the laser 16 is oscillated by the CW laser and is pulsed by the external shutter disk 18, the laser 16 may be inexpensive with poor optical response. The shutter disk 18 is formed, for example, by stamping a metal plate into the above-described shape, or on a disk plate that does not absorb the output light of the laser 16 by applying a material that completely reflects or absorbs the output light of the laser 16 to the above-described pattern. May be adhered to (e.g., vapor deposition).

Since the shutter disk 18 is rotating at a high speed, it is in an air-cooled state, so that, if a normal metal having a high thermal conductivity is used, even if a high-power laser beam from the laser 16 hits the fin 18a, There is no danger of melting, and there is no need to use a material with particularly high heat resistance. Therefore, in this embodiment, a high-power pulse light can be obtained at very low cost.

In the present embodiment, the tie / cut ratio can be adjusted by adjusting the offset amount of the shutter disk 18 with respect to the output light of the laser 16, so that the tie / cut ratio can be easily changed. Further, by exchanging the shutter disk 18, a flexible perforation pattern can be realized.

Although the embodiment of the vertical perforation has been described, the laser beam passing through the shutter disk 18 may be scanned in the horizontal direction of the sheet 10 by a polygon mirror or the like for the horizontal perforation.

In the above embodiment, the shutter disk 18
The laser 16 itself can be moved laterally with respect to the optical axis of the output laser light of the laser 16, but the shutter disk 18 (motor 20) is fixed, and the optical axis of the laser light is set to the rotation axis of the shutter disk 18. You may make it possible to approach and move away. FIG. 3 shows a perspective view of the modified embodiment.
The same components as those in FIG. 1 are denoted by the same reference numerals.

The laser 30 is arranged so as to output a laser beam parallel to the sheet 10, and the mirror 32 rotates the laser beam from the laser 30 by 90 degrees and directs the laser beam toward the sheet 10.
The shutter disk 18 is provided between the mirror 32 and the sheet 10.
Is arranged. The mirror 30 is movable in parallel with the sheet 10, and by moving the mirror 30, the amount of deviation of the optical axis of the laser beam from the rotation center axis of the shutter disk 18 can be adjusted. The motor 20 for rotating the shutter disk 18 is fixed.

In the above-described embodiment, the shutter disk 18 has a propeller shape having a plurality of fins. However, the shutter disk 18 may have many holes of a desired size in each part of the disk. By changing the number and size of the holes in the angular direction depending on the radius, the pattern of the perforations can be changed and selected more flexibly simply by changing the amount of displacement of the shutter disk from the optical axis.

[0024]

As can be easily understood from the above description, according to the present invention, perforations can be formed with an inexpensive configuration, and the tie / cut ratio can be easily changed. Further, an arbitrary perforation pattern can be easily realized.

[Brief description of the drawings]

FIG. 1 is a perspective view of one embodiment of the present invention.

FIG. 2 is a front view of the shutter disk 18 of the embodiment.

FIG. 3 is a perspective view of a modified embodiment of the present invention.

[Explanation of symbols]

 10: paper 12, 14: guide roller 16: laser 18: shutter disk 18a: fin 20: motor 22: support plate 24: formed perforation 30: laser 32: mirror

Claims (3)

[Claims] 1. A laser light source comprising: a laser light source; and a rotation driving means, wherein a light-shielding portion that shields a laser beam output from the laser light source and a light-transmitting portion that passes the laser beam are alternately arranged around a rotation axis. A shutter means in which the ratio of the angular width between the light-shielding part and the light-transmitting part on the circumference of an arbitrary radius position about the rotation axis differs depending on each radial position; Moving means for relatively changing the distance between the optical axis of the laser light and the rotation axis of the shutter means when passing through, and transporting a paper sheet which is a subject of the laser light and is to be formed with perforations. A perforation forming apparatus, comprising: 2. The perforation forming apparatus according to claim 1, wherein the light shielding portions have the same angular width on a circumference at an arbitrary radial position. 3. The perforation forming apparatus according to claim 1, wherein the laser light output from the laser light source is continuous light.