JP2010221291A - Laser beam machining apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser beam machining apparatus in which intensity of a laser beam used for machining can be measured even during the machining and in which machining by laser beam can be stably performed. <P>SOLUTION: The laser beam machining apparatus 10 for machining a workpiece by irradiating it with a laser beam includes: a laser oscillator 11 for oscillating the laser beam; a laser beam controller 30 having an acousto-optical element that adjusts the intensity of the laser beam used for machining; a partial reflection plate 61 that is arranged on a laser path on which the laser beam passes and that reflects a part of the laser beam and transmits the remaining laser beam; and an intensity calculating means 63 that calculates the intensity of the laser beam which has passed through the partial reflection plate, by measuring the intensity of the laser beam reflected by the partial reflection plate 61. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a laser processing apparatus that irradiates a workpiece with laser light and performs processing on the workpiece.

  As the above-described laser processing apparatus, for example, as disclosed in Patent Documents 1 and 2, a laser oscillator that oscillates laser light, and the laser light oscillated from the laser oscillator is reflected to change the course of the laser light. A thing provided with a mirror member, a lens member which adjusts the beam diameter of a laser beam, and a processing head which irradiates a laser beam to a work is provided.

  In such a laser processing apparatus, since the processing depth in the workpiece is adjusted by controlling the intensity of the laser beam, the intensity control of the laser beam is important. In particular, for example, in the case where a relief plate is formed on the outer peripheral surface of a sleeve-like printing plate, the processing depth by laser processing greatly affects the print quality, so it is necessary to adjust the intensity of the laser beam particularly accurately. .

In the laser processing apparatus described above, the output of the laser beam oscillated from the laser oscillator is kept constant, and the intensity of the laser beam is adjusted using a laser beam control unit equipped with an acousto-optic modulator (AOM). is doing.
Here, when the intensity of the laser light incident on the laser light control unit varies, the intensity of the laser light used for processing cannot be accurately controlled.

  Therefore, in order to confirm the intensity of the laser beam incident on the laser beam control unit, an output meter is installed on the front side of the laser beam control unit before laser processing to measure the laser beam intensity. Was.

Japanese Unexamined Patent Publication No. 07-256477 Japanese Patent Laid-Open No. 02-150085

However, as described above, the method of measuring the intensity of laser light by installing an output meter can measure the intensity of laser light only in a state where laser processing is stopped. For this reason, the intensity fluctuation of the laser beam generated during the laser processing cannot be dealt with at all, and the intensity fluctuation of the laser beam can be detected only after a defect or the like occurs on the workpiece. Therefore, it has been difficult to stably process the workpiece for a long time.
Even when the laser output in the laser oscillator is constant, if the mirror member or lens member disposed in the laser path where the laser light is transmitted to the laser light control unit has deteriorated, There is a risk that fluctuations in the intensity of the laser light incident on the laser light control unit may occur during laser processing.

  The present invention has been made in view of the above circumstances, and can perform laser processing that can measure the intensity of laser light used for processing even during processing, and can stably perform processing using laser light. An object is to provide an apparatus.

  In order to solve the above-described problems, a laser processing apparatus according to the present invention is a laser processing apparatus that processes a workpiece by irradiating a laser beam, and is used for processing a laser oscillator that oscillates the laser beam. A laser light control unit that adjusts the intensity of the laser light, a partial reflector that is disposed on a laser path through which the laser light passes, reflects a part of the laser light and transmits the remaining laser light, and Intensity calculating means for calculating the intensity of the laser light that has passed through the partial reflection plate by measuring the intensity of the laser light reflected by the partial reflection plate.

  According to the laser processing apparatus of this configuration, the laser beam is arranged on the laser path through which the laser beam passes, reflects a part of the laser beam and transmits the remaining laser beam, and reflects by the partial reflector. Intensity calculation means for calculating the intensity of the laser beam that has passed through the partial reflector by measuring the intensity of the laser beam that has been measured, so that laser processing is performed with the laser beam that has passed through the partial reflector It is possible to measure the intensity of laser light even when laser processing is being performed. In other words, by grasping the reflectance and transmittance of the partial reflector in advance, it is possible to calculate the intensity of the laser beam that is transmitted and used for processing from the intensity of the reflected laser beam. is there.

Here, it is preferable that the partial reflection plate is disposed immediately before the laser light incident part of the laser light control part.
In this case, the intensity of the laser light incident on the laser light control unit that adjusts the intensity of the laser light can be measured, and the intensity adjustment of the laser light in the laser light control unit can be accurately performed. Therefore, the workpiece can be processed stably.

Moreover, it is preferable to provide an output adjusting means for adjusting the output of the laser oscillator based on the intensity of the laser light calculated by the intensity calculating means.
In this case, for example, even if the mirror member or lens member disposed in the laser path through which the laser light oscillated from the laser oscillator is transmitted to the laser light controller is deteriorated, the output of the laser oscillator is increased. The intensity of the laser light incident on the laser light control unit can be kept constant. Therefore, laser processing can be performed more stably. Further, even if the intensity of the laser beam varies during the processing of the workpiece, the intensity of the laser beam used for the processing is controlled with high accuracy, and the processing can be performed stably.

Further, in the partial reflector, it is preferable that the reflectance is set to 1% to 50% and the transmittance is set to 50% to 99%.
In this case, since the reflectance of the partial reflector is 1% or more and 50% or less, the output of the reflected laser light can be measured. Furthermore, since the transmittance of the partial reflector is 50% or more and 99% or less, the workpiece can be reliably processed by the transmitted laser light.

  ADVANTAGE OF THE INVENTION According to this invention, the intensity | strength of the laser beam used for a process can be measured even during a process, and the laser processing apparatus which can perform the process by a laser beam stably can be provided.

It is explanatory drawing of the laser processing apparatus which is one Embodiment of this invention.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
The laser processing apparatus 10 according to the present embodiment is used, for example, when a relief printing plate is formed on the outer peripheral surface of a cylindrical sleeve printing plate.
A laser processing apparatus 10 shown in FIG. 1 includes a laser oscillator 11 that oscillates laser light having a wavelength in the infrared region, a shutter unit 12 that blocks the laser light oscillated from the laser oscillator 11, and a laser that reflects the laser light. A first mirror member 21 that changes the path of the light, a compounder 15 that reduces the beam diameter of the laser light, and a second mirror member 22 that reflects the laser light whose beam diameter has been reduced and changes the path of the laser light. A laser light control unit 30 that adjusts the intensity of the laser light, a third mirror member 23 that reflects the laser light that has passed through the laser light control unit 30 and changes the path of the laser light, and the beam diameter of the laser light. An expander 17 that expands, a fourth mirror member 24 that reflects the laser beam having an enlarged beam diameter and changes the path of the laser beam, A machining head 18 for irradiating Za light to the work W, and includes a.

  The laser oscillator 11 includes an optical resonator filled with carbon dioxide, and is configured to oscillate laser light by amplifying light in the optical resonator by stimulated emission in the carbon dioxide. From the laser oscillator 11 using the carbon dioxide gas, laser light in the infrared region having a wavelength of about 10.6 μm is oscillated. The laser oscillator 11 is always in a state of emitting laser light in order to stably oscillate laser light.

  The shutter member 12 is movable so as to block the laser light oscillated from the laser oscillator 11. When the shutter member 12 is moved on the path of the laser beam, the laser beam is reflected by the shutter member 12 and irradiated to the beam absorber 13. The beam absorber 13 converts the energy of the irradiated laser light into heat and absorbs it by cooling.

The first mirror member 21 reflects the laser light oscillated from the laser oscillator 11 and transmits the laser light to the compounder 15. The first mirror member 21 is provided with a drive unit 21a for adjusting the position and angle.
The compounder 15 is disposed so that a plurality of lenses are stacked in the traveling direction of the laser beam, and reduces the beam diameter of the laser beam. In this embodiment, the beam diameter of about 20 mm is reduced to about 5 mm.
The second mirror member 22 reflects the laser light that has passed through the compounder 15 and transmits the laser light to the laser light control unit 30. The second mirror member 22 is provided with a drive unit 22a for adjusting the position and angle.

The laser light control unit 30 can modulate the intensity of the laser light by an acoustic wave, and can change the traveling direction of the laser light passing therethrough by changing its refractive index (Acosto-Optic). Modulator: AOM / Acosto-Optical Defect: AOD).
In the laser light control unit 30, the processing depth of the workpiece W by the laser light is adjusted by modulating the intensity of the laser light. Further, the ON / OFF control of the processing by the laser beam is performed by deflecting the traveling direction of the laser beam.

  The third mirror member 23 reflects the laser light that has passed through the laser light control unit 30. Here, when the laser beam is deflected in the laser beam control unit 30, the laser beam reflected by the third mirror member 23 is irradiated to the beam absorber 16, as indicated by a dotted line in FIG. It is configured. On the other hand, when the laser light is not deflected by the laser light control unit 30, the laser light is transmitted to the explorer 17 as indicated by a solid line in FIG. 1. The third mirror member 23 is provided with a drive unit 23a for adjusting the position and angle.

The expander 17 is disposed so that a plurality of lenses are laminated in the traveling direction of the laser light, and expands the beam diameter of the laser light. In this embodiment, the beam diameter of about 5 mm is increased to about 20 mm.
The fourth mirror member 24 reflects the laser light that has passed through the expander 17 and transmits the laser light to the processing head 18. The fourth mirror member 24 is provided with a drive unit 24a for adjusting the position and angle.
The processing head 18 processes the workpiece W by irradiating the workpiece W with laser light.

In the present embodiment, a partial reflector 61 that reflects part of the laser light and transmits the remaining laser light to the upstream side (laser oscillator 11 side) of the laser light control unit 30, and this partial reflector An intensity measuring unit 62 that measures the intensity of the reflected light reflected by 61 is provided.
Further, based on the intensity of the laser beam measured by the intensity measuring unit 62, a calculation unit 63 that calculates the intensity of the laser beam that has passed through the partial reflector, and the intensity of the laser beam calculated by the calculation unit 63, An adjustment unit 64 that transmits a control signal for adjusting the laser output to the laser oscillator 11 is provided.

Here, the partial reflector 61 is set to have a reflectance of 1% to 50% and a transmittance of 50% to 99%. In this embodiment, for example, the reflectance is 2% and the transmittance is 98. %.
Therefore, the intensity of the laser light reflected by the partial reflection plate 61 is 2% of the total laser light, and the intensity of the transmitted laser light is 98% of the total laser light, so that it is reflected by the partial reflection plate 61. The intensity of the laser light transmitted through the partial reflector 61 is calculated from the intensity of the laser light.

  According to the laser processing apparatus 10 of the present embodiment configured as described above, a partial reflector that reflects part of the laser light and transmits the remaining laser light on the laser path through which the laser light passes. 61 is disposed, and the intensity of the laser light that has passed through the partial reflector 61 can be calculated by the calculator 63 by measuring the intensity of the laser light reflected by the partial reflector 61 by the intensity measuring unit 62. It becomes. Here, since it can process with the laser beam which permeate | transmitted the partial reflector 61, the intensity | strength measurement of a laser beam can be performed also in the state which is implementing laser processing. Therefore, the workpiece W can be processed stably.

  In this embodiment, since the partial reflector 61 is arranged immediately before the laser light incident part of the laser light control part 30, the laser light incident on the laser light control part 30 that adjusts the intensity of the laser light. The intensity can be reliably measured, the intensity of the laser light incident on the laser light control unit 30 becomes constant, and the laser light intensity adjustment in the laser light control unit 30 can be performed with high accuracy. Therefore, the machining depth of the workpiece can be accurately controlled, and the machining quality can be improved.

  Further, since the adjustment unit 64 that adjusts the output of the laser oscillator 11 based on the intensity of the laser light calculated by the calculation unit 63 is provided, the laser light oscillated from the laser oscillator 11 is transmitted to the laser light control unit 30. Even when the first mirror member 21, the compounder 15, and the second mirror member 22 disposed until transmission is deteriorated and the intensity of the laser beam fluctuates, the laser oscillator 11 is controlled by a control signal from the adjustment unit 64. By increasing the output, the intensity of the laser light incident on the laser light control unit 30 can be kept constant. Therefore, even if the intensity of the laser beam varies during the machining of the workpiece, the intensity of the laser beam used for machining is controlled with high accuracy, and the machining can be performed stably.

  Further, in the partial reflector 61, the reflectance is set to 1% to 50% and the transmittance is set to 50% to 99%. In this embodiment, the reflectance is 2% and the transmittance is 98%. Since it is set, the output of the laser beam reflected by the partial reflection plate 61 can be reliably measured, and the workpiece can be reliably processed by the laser beam transmitted through the partial reflection plate.

As mentioned above, although embodiment of this invention was described, this invention is not limited to this, It can change suitably in the range which does not deviate from the technical idea of the invention.
For example, in the present embodiment, the description has been made assuming that the partial reflector is disposed immediately before the laser light control unit. However, the present invention is not limited to this, and the partial reflector is disposed on another laser path. Also good.
Further, the number of mirror members, the number of lens members, the arrangement of laser oscillators, and the like are not limited to this embodiment, and can be appropriately changed in design.

DESCRIPTION OF SYMBOLS 10 Laser processing apparatus 11 Laser oscillator 30 Laser light control part 61 Partial reflector 62 Strength measurement part 63 Calculation part (Intensity calculation means)
64 Adjustment unit (output adjustment means)

Claims (4)

A laser processing apparatus for processing a workpiece by irradiating a laser beam,
A laser oscillator for oscillating the laser beam;
A laser beam control unit that adjusts the intensity of the laser beam used for processing;
A partial reflector arranged on a laser path through which the laser light passes, reflects a part of the laser light and transmits the remaining laser light;
An intensity calculating means for calculating the intensity of the laser light that has passed through the partial reflector by measuring the intensity of the laser light reflected by the partial reflector;
A laser processing apparatus comprising:   The laser processing apparatus according to claim 1, wherein the partial reflection plate is disposed immediately before a laser light incident part of the laser light control part.   3. The laser processing apparatus according to claim 1, further comprising an output adjusting unit that adjusts an output of the laser oscillator based on the intensity of the laser beam calculated by the intensity calculating unit.   4. The partial reflection plate according to claim 1, wherein the reflectance is set to 1% to 50% and the transmittance is set to 50% to 99%. The laser processing apparatus described in 1.

Images