JPH0579439B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a laser drilling device for drilling holes in a workpiece such as paper, plastic film, or metal plate using a laser beam.

[Prior Art] Conventionally, as a laser drilling device, one disclosed in, for example, Japanese Patent Laid-Open No. 59-42194 is known.

FIG. 4 is a schematic diagram showing the configuration of a conventional laser drilling device. In the figure, 1 is a long workpiece such as paper or plastic film, 2 is a speed detector such as a tachometer generator that detects the moving speed of the workpiece 1 and generates a voltage proportional to the moving speed, and 3 is a speed detector. A pulse generator constitutes a voltage-frequency converter (V/F) which receives the detection signal of the speed detector 2 and generates a frequency proportional to the detection signal of the speed detector 2; 4 is the signal of the pulse generator 3; 5 is a duty setting device that outputs a duty setting value signal; 6 is a slope signal of the slope generator 4; and a duty setting value signal of the duty setting device 5 are respectively input, and a drilling pulse signal generator generates a signal with a pulse width necessary for drilling a predetermined hole in the workpiece 1, and 7 is a drilling pulse signal generator. 6
8 is a laser output setting device that generates a signal to set a laser output proportional to the signal from speed detector 2; 11 is a pulse laser oscillator that outputs pulsed laser light 12; 13 is a pulse laser Bend mirror that reflects light 12, 1
4 is a lens.

FIG. 5 is a diagram for explaining the operation of the laser drilling device shown in FIG. 4.

Next, the operation of the conventional laser drilling apparatus shown in FIG. 4 will be explained. First, when a long workpiece 1 such as paper or plastic film is moved in the direction of the arrow in FIG. 4, a speed detector 2 such as a tachogenerator that detects the moving speed generates a voltage proportional to the moving speed. do. Since the pulse generator 3 constitutes a voltage-frequency converter (V/F), it converts the output voltage of the speed detector 2 into a pulse frequency and outputs it, and the output waveform is shown in FIG. 5a. The slope generator 4 generates a slope signal of a frequency such that the pitch of drilling holes in the workpiece 1 is constant based on the signal from the pulse generator 3, and the output waveform thereof is shown in FIG. 5b. Further, the drilling pulse signal generator 6 generates pulses necessary for drilling a predetermined hole in the workpiece 1 based on input of the slope signal generated by the slope generator 4 and the duty setting value signal of the duty setting device 5. generates a pulse signal with a width of
The output waveform is shown in FIG. 5c. The switch 7 is opened and closed based on the pulse signal generated by the drilling pulse signal generator 6. Further, the laser output setting device 8 generates a signal for setting the laser output proportional to the signal from the speed detector 2, and the signal is inputted to the pulse laser oscillator 11 via the switch 7, and its output waveform is shown in FIG. Shown in d. By transmitting the signal output by the laser output setting device 8 to the pulse laser oscillator 11, the pulse laser oscillator 11 outputs a pulse laser beam 12 whose pulse peak value is proportional to the workpiece 1. Note that since the signal for setting the laser output from the laser output setting device 8 is proportional to the moving speed of the workpiece 1, the optimal laser output can always be obtained even if the moving speed of the workpiece 1 changes. The pulsed laser beam 12 output from the pulsed laser oscillator 11 is transmitted to the bend mirror 13.
The light is reflected by the lens 14 and focused onto the workpiece 1, so that the workpiece 1 has a predetermined pulse width and a predetermined interval (pitch) as shown in FIG. This means that holes of each predetermined shape can be continuously drilled.

[Problems to be Solved by the Invention] Since the conventional laser drilling device described above is configured as described above, the pulse laser oscillator 11
When the pulsed laser beam 12 outputted from the pulsed laser oscillator 12 is condensed and irradiated onto the workpiece 1 via the bend mirror 13 and the lens 14, the laser output from the pulsed laser oscillator 11 decreases because its focal length is fixed. There is a limit to the speed at which holes can be drilled in the workpiece 1 due to the pulse response speed. Further, the shorter the pitch of the holes drilled in the workpiece 1 and the closer the shape is to a perfect circle, the faster the pulse laser oscillator 11 with a faster pulse response speed is required. As a result, it is possible to realize a laser drilling device that can drill minute holes on the workpiece 1 with a high pitch and at a high speed, and in particular can drill holes that are close to a perfect circle at a high speed. The problem was that it was extremely difficult.

This invention was made in order to solve such problems, and even with a pulse laser oscillator having a relatively slow pulse response speed, it is possible to create laser holes with a high pitch and at a high speed. The purpose is to obtain an opening device.

[Means for Solving the Problems] The laser drilling device according to the present invention uses a signal from a pulse generator that generates a frequency proportional to a detection signal from a speed detector that detects the moving speed of the workpiece to perform the above-mentioned A slope signal with a frequency that keeps the pitch of drilling holes in the workpiece constant is generated by a slope generator, and in synchronization with this slope signal, a signal with a pulse width necessary for drilling a predetermined hole is generated. A drilling pulse signal generator is provided, a switch is opened and closed by the signal of this drilling pulse signal generator, and a laser output proportional to the signal of the speed detector generated by the laser output setting device is set via this switch. A scanner mirror driving device is provided that transmits a signal to the pulse laser oscillator and drives a scanner mirror using the signal from the slope generator, and the pulse laser beam output from the pulse laser oscillator is transmitted onto the workpiece through an optical system. The scanner mirror driving device controls the angle of the scanner mirror in order to move the focal position of the pulsed laser beam in the same direction as the moving speed of the workpiece when condensing and irradiating the object.

[Function] In the laser drilling device of the present invention, the scanner mirror driving device can drive the scanner mirror using the signal from the slope generator and control its angle, so that the pulse laser beam output from the pulse laser oscillator can be optically controlled. When condensing irradiation onto the workpiece through the system, it is possible to move the focal position of the pulsed laser beam in the same direction as the movement factor of the workpiece, which makes it possible to Even with a pulsed laser oscillator that has a slow pulse response speed, it is possible to open minute holes at a high pitch and at a high speed.

[Example] Fig. 1 is a schematic diagram showing the configuration of a laser drilling device which is an embodiment of the present invention, and the same or corresponding parts as in Fig. 4 are indicated using the same reference numerals. Explanation will be omitted. In the figure, 9 is a scanner mirror, and 10 is a scanner mirror drive device that drives the scanner mirror 9 using a signal from the slope generator 4.

FIG. 2 is a diagram for explaining the operation of the laser drilling device shown in FIG. 1.

Next, the operation of the laser drilling device shown in FIG. 1, which is an embodiment of the present invention, will be described.
First, when a long workpiece 1 such as paper or plastic film is moved in the direction of the arrow in FIG.
A speed detector 2 such as a tachometer generator that detects the moving speed generates a voltage proportional to the moving speed. Since the pulse generator 3 constitutes a voltage-frequency converter (V/F), it converts the output voltage of the speed detector 2 into a pulse frequency and outputs it, and the output waveform is shown in FIG. 2a. The slope generator 4 generates a slope signal having a frequency such that the pitch of drilling holes in the workpiece 1 is constant based on the signal from the pulse generator 3, and the output waveform thereof is shown in FIG. 2b.
Further, the drilling pulse signal generator 6 synchronizes with the signal of the slope generator 4 and generates a pulse signal of a fixed width necessary for drilling a predetermined hole from the time when the signal reaches a certain level, and its output waveform is shown in Figure 2c. The switch 7 is opened and closed based on the pulse signal generated by the drilling pulse signal generator 6. Further, the laser output setting device 8 generates a signal for setting the laser output proportional to the signal from the speed detector 2, and this signal is inputted to the pulse laser generator 11 via the switch 7, and the output waveform is Shown in Figure d. By transmitting the signal output by the laser output setting device 8 to the pulse laser oscillator 11, the pulse laser oscillator 11 outputs a pulse laser beam 12 whose pulse peak value is proportional to the workpiece 1. Note that since the signal for setting the laser output from the laser output setting device 8 is proportional to the moving speed of the workpiece 1, the optimal laser output can always be obtained even if the moving speed of the workpiece 1 changes.

On the other hand, since the scanner mirror driving device 10 can drive the scanner mirror 9 using the signal from the slope generator 4 and control its angle, the pulse laser beam 12 outputted from the pulse laser oscillator 11 is transferred to the bend mirror 13, the lens 14, When condensing and irradiating the workpiece 1 through an optical system such as the scanner mirror 9, the focal position of the pulsed laser beam 12 can be moved in the same direction as the moving speed of the workpiece 1. Therefore, by controlling the angle of the scanner mirror 9 as shown in FIG.
If the moving speed is the same as that of the second
As shown in Figure g, a perfectly circular hole can be made. Also, the angle of the scanner mirror 9 is shown in Fig. 2 f.
When the angle control is slowed down to make the moving speed of the focal position of the pulsed laser beam 12 slower than the moving speed of the workpiece 1, as shown in FIG.
An oblong hole can be drilled as shown in Figure h.

Furthermore, the highest pulse frequency that the pulse laser oscillator 11 can output is when the duty is 50%, and according to the invention of this application, even when the duty is 50%, the pulse laser oscillator 11 can be output by controlling the angle of the scanner mirror 9. It is possible to drill holes of any shape at the highest frequency that can be output. In other words, the workpiece 1 can be moved at the fastest speed for drilling at a given pitch.

FIG. 3 is a schematic diagram showing the configuration of the main parts of a laser drilling device according to another embodiment of the present invention. In the figure, 9 is a scanner mirror, 12 is a pulsed laser beam, 14 is a lens, 15 is a piezoelectric actuator as an element for driving the scanner mirror 9, and 16 is a piezoelectric actuator.
is a signal generator that generates a drive signal for the piezoelectric actuator 15. What is shown in FIG. 3 is a case where a piezoelectric actuator 15 is used as an element for driving the scanner mirror 9. In FIG. The piezoelectric actuator 15 has a very fast pulse response speed of several KHz.
As a result, it is possible to vibrate at a speed sufficiently high for drilling a hole in the workpiece 1.

[Effects of the Invention] As described above, the present invention provides a laser drilling device in which the scanner mirror drive device drives the scanner mirror using a signal from a slope generator to control its angle, and outputs an output from a pulse laser oscillator. When condensing and irradiating the pulsed laser beam onto the workpiece through the optical system,
Since the focal position of the pulsed laser beam can be moved in the same direction as the moving speed of the workpiece, even if a pulsed laser oscillator with a relatively slow pulse response speed is used, it is possible to drill a minute hole with a high height. It has excellent effects such as being able to drill holes in pitches and at high speed, and also being able to continuously drill perfectly circular or oval holes with high precision.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the configuration of a laser drilling device which is an embodiment of the present invention, FIG. 2 is a diagram for explaining the operation of the laser drilling device shown in FIG. 1, and FIG.
The figure is a schematic diagram showing the configuration of the main parts of a laser drilling device according to another embodiment of the present invention, FIG. 4 is a schematic diagram showing the configuration of a conventional laser drilling device, and FIG. It is a figure for explaining operation of a laser drilling device. In the figure, 1...Workpiece, 2...Speed detector, 3...Pulse generator, 4...Slope generator, 5...Duty setting device, 6...Drilling pulse signal generator, 7... ...Switch, 8...Laser output setting device, 9...Scanner mirror, 10...Scanner mirror drive device, 11...Pulse laser oscillator, 12...Pulse laser beam, 13...Bend mirror, 14...Lens, 15... . . . piezoelectric actuator, 16 . . . signal generator. In addition, in the figure,
The same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. A laser drilling device that continuously forms holes of a predetermined shape at predetermined intervals in a long workpiece that is moved by a moving means using intermittent laser light, wherein the workpiece is a speed detector that detects the moving speed of the workpiece; a pulse generator that receives the detection signal of the speed detector and generates a frequency proportional to the detection signal of the speed detector; and a pulse generator that generates a frequency proportional to the detection signal of the speed detector; A slope generator that generates a slope signal with a frequency that makes the pitch of drilling a hole in an object constant, and a hole generator that generates a signal with a pulse width necessary for drilling a predetermined hole in synchronization with the signal of this slope generator. a drilling pulse signal generator; a switch that opens and closes according to a signal from the drilling pulse signal generator;
a laser output setting device that generates a signal for setting a laser output proportional to the signal of the speed detector; a scanner mirror drive device that drives the scanner mirror according to the signal of the slope generator; and a pulsed laser oscillator that outputs a pulsed laser beam. and an optical system that guides the pulsed laser beam oscillated from the pulsed laser oscillator to the scanner mirror. 2 As an element for driving the above scanner mirror,
A laser drilling device according to claim 1, characterized in that a piezoelectric actuator is used.