JP6782653B2 - Laser processing equipment - Google Patents

Description

The present invention relates to a laser processing apparatus.

A conventional laser machining apparatus is provided with a laser light source, a propagation optical system, a deflector, an fθ lens, etc. Processing such as drilling is performed.
By the way, when pulsed laser oscillation is performed from a laser light source, the output of the laser changes depending on the oscillating frequency.
The laser machining apparatus repeatedly moves to the machining position and irradiates with a deflector to perform drilling. Therefore, as shown in FIG. 5, the laser processing apparatus performs pulse oscillations P1 to P3 (hereinafter referred to as "pulse oscillation for processing") at a constant oscillation frequency.
However, if the next work position is far away and the movement by the deflector is not in time for the oscillation according to the oscillation frequency of the laser, the propagation optical system is controlled so that the laser beam is not irradiated to the object to be processed. , A dummy laser oscillation PD that does not contribute to processing was executed. Then, at the time of the next pulse oscillation P3, the hole to be machined was drilled (see, for example, Patent Document 1).

Japanese Patent No. 4873578

In the conventional laser machining apparatus, when the dummy laser oscillation PD is executed, an interval of two cycles is generated between the pulse oscillation P2 for machining and the pulse oscillation P3 for machining. In this case, as shown in FIG. 5, when the settling time Th by the deflector is shorter than two cycles, there is a problem that an unnecessary waiting time Tu is generated and the processing speed is lowered.
The above-mentioned unnecessary waiting time Tu may be a minute time such as a millisecond order or a microsecond order, but in the field of laser machining, the number of workpiece positions for one machining object is large. In many cases, if the delay accumulates, the delay in the machining speed for one machining object becomes large, so there is a demand for sufficiently reducing the delay in the machining speed that occurs in one dummy pulse.

An object of the present invention is to provide a laser processing apparatus capable of increasing the processing speed while maintaining stable output.

The present invention comprises a laser light source, a deflector, a switching element that irradiates a dummy laser light by switching the diffraction direction of the laser light from the laser light source, the laser light source , the deflector, and the laser processing apparatus. A control device for controlling the switching element is provided, and the control device includes a first laser beam for drilling emitted from the laser light source and a second laser beam for drilling emitted from the laser light source. , Controls to emit the third laser beam for drilling emitted from the laser light source, and from the time between the first laser beam for drilling and the second laser beam for drilling. Also, when the time between the second laser beam for drilling and the third laser beam for drilling is long, the second laser beam for drilling and the third laser beam for drilling are used. The time between the second laser beam for drilling and the third laser beam for drilling is determined from the pattern that determines the position of the hole to be machined. It is defined based on the obtained movement time of the deflector, and the control device is defined by the time interval between the first laser beam for drilling and the second laser beam for drilling, and the dummy laser. The time interval between the light and the third laser beam for drilling is controlled to be aligned, the time interval between the first laser beam for drilling and the second laser beam for drilling, and the dummy laser beam. And the time interval of the third laser beam for drilling are both the charge time in the pulse oscillation of the laser light source .

As described above, according to the present invention, it is possible to provide a laser processing apparatus capable of increasing the processing speed while maintaining the stability of the output.

It is the schematic of the laser processing apparatus according to an Example. It is a flowchart which shows the operation control of the drilling process by the control device of the laser processing apparatus according to an Example. It is a timing chart which shows the operation which emits a dummy laser beam during the operation of drilling. FIG. 4A is a timing chart showing the operation timing of the deflector, and FIG. 4B is a timing chart showing the emission timing of the laser beam for drilling the laser light source. It is a timing chart which shows the operation which emits a dummy laser light during the operation of drilling of a conventional laser processing apparatus.

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

[Outline of laser processing equipment]
FIG. 1 is a configuration diagram showing a laser processing apparatus 10 according to an embodiment of the present invention. In FIG. 1, the laser beam is shown by a solid line, and the signal line is shown by a broken line.

The laser processing device 10 includes a laser light source 20, a switching element 30, a folding mirror 41, a deflector 50, an fθ lens 42, an XY stage 60, and a control device 70.
Then, the switching element 30, the folding mirror 41, the deflector 50, and the fθ lens 42 are arranged in this order along the path of the laser light incident on the processing object W on the XY stage 60 from the laser light source 20. There is.

The laser light source 20 is, for example, a gas laser such as a CO ₂ laser or a solid-state laser such as a YAG laser or a YLF laser, and performs pulse oscillation by mode synchronization. It is also possible to perform pulse oscillation using a Q switch.

The switching element 30 can switch between an open state in which the laser light from the incident laser light source 20 is incident on the folded mirror 41 and a closed state in which the laser light from the incident laser light source 20 is incident on the beam damper 31. That is, when the switching element 30 is in the open state, the laser light is incident on the machining object W, and when the switching element 30 is in the closed state, the laser light is not incident on the machining object W.
Switching between the closed state and the open state of the switching element 30 is performed by a control signal from the control device 70. For example, the switching signal from the control device 70 is constantly in the OFF state, and at this time, the switching element 30 is maintained in the closed state. Further, the switching element 30 is momentarily switched to the open state only when the switching signal from the control device 70 rises to the ON state, so that the laser beam is incident on the folded mirror 41.
Specifically, as the switching element 30, an acoustic optical element (AOM), an acoustic optical deflection element (AOD), or the like can be used.

The folded mirror 41 is a mirror that reflects the laser light incident from the laser light source 20 via the switching element 30 toward the deflector 50.

The deflector 50 is a galvano scanner that includes a pair of movable mirrors. The deflector 50 can reflect the laser beam incident from the folded mirror 41 toward an arbitrary work position within a predetermined range of the object W to be processed by a galvano mirror that changes the angle within a certain movable range. ..
The deflector 50 can change the angle at which the galvanometer mirror reflects the laser beam to the target position to be processed from the control signal from the control device 70. Further, the deflector 50 sends a settling signal to the control device 70 when the galvano mirror is changed to a target angle.

The fθ lens 42 concentrates the laser light reflected from the galvano mirror of the deflector 50 on the surface of the object W to be processed. Further, the fθ lens 42 causes the laser beam reflected by the galvano mirror whose angle is changed in the movable range to be incident perpendicular to the processing surface of the processing object W.

The XY stage 60 arbitrarily moves the workpiece W along the horizontal plane by a control signal from the control device 70. Further, when the machining object W is moved to the target position, the XY stage 60 sends a movement completion signal to the control device 70.
The moving range of the object W to be machined by the XY stage 60 is significantly wider than the operating range by the deflector 50.
Therefore, at the time of laser machining, while the machining object W on the XY stage 60 is stationary, machining is performed within a scantable range based on the movable range of the galvano mirror of the deflector 50, and the scannable range of the galvano mirror is performed. When the machining of the work position inside is completed, the machining target W by the XY stage 60 is moved, and the machining with the galvano mirror is performed for a new range.
The above control is an example, and the deflector 50 and the XY stage 60 may perform synchronous scanning. That is, the scanning of the galvano mirror and the movement of the XY stage 60 may be performed in parallel within the range that the galvano mirror can follow.

The control device 70 is a computer having a storage device in which the program is stored, a CPU (Central Processing Unit) for executing the program, a working memory, and an interface for inputting / outputting control signals and detection signals.
Further, the control device 70 includes a storage unit 71 that stores data of a machining pattern that defines a machining position which is a formation position of a series of holes with respect to the machining object W and the order thereof. Then, the control device 70 controls the laser light source 20, the switching element 30, the deflector 50, and the XY stage 60 according to the processing pattern data in the storage unit 71, and executes drilling processing for the processing object W.

[Control of drilling of laser machining equipment]
Hereinafter, the control of the drilling process executed by the control device 70 will be described with reference to the flowchart shown in FIG.
As described above, in the laser processing device 10, since the laser light source 20 emits the laser beam for drilling by pulse oscillation, the laser beam for drilling is emitted at a constant frequency in order to stabilize the output. It is assumed that the light is controlled to be emitted sequentially.
The constant frequency in this case means that the time from immediately after the completion of the emission of the laser beam immediately before to the start of the emission of the laser beam for the next drilling, that is, the charging time of the laser light source 20 is made constant. Further, "constant charge time" is not limited to a perfect match, and it is sufficient that the "charge time" can maintain a constant time range. For example, each of the holes formed may have a range (for example, ± several percent) in terms of "time" to the extent that the required processing quality can be maintained. In the following explanation, the "charge time" considering this width is defined as the specified charge time Ts.

First, the control device 70 executes reading of the machining position in order from the machining pattern data stored in the storage unit 71 (step S1).

Then, the moving distance is obtained from the position to be machined to be drilled next and the position to be machined immediately before it, and the time required to move to the position to be machined to be drilled next is obtained by the deflector 50. (Step S3).
As described above, since the processing pattern data stores a plurality of processing positions and their order, the moving distance from the previous processing position to the processing position where drilling is executed is calculated. can do.
Further, in the storage unit 71 of the control device 70, table data showing the relationship between the moving distance and the required moving time Tm (or table data showing the relationship between the required operating time of the galvano scanner according to the moving distance) is prepared. ing.
Therefore, the control device 70 refers to the table data from the moving distance from the previous machined position to the machined position where the drilling is executed, and the time required to move to the machined position where the drilling is performed next. Can be obtained.

Next, the control device 70 determines whether or not the acquired movement time required Tm exceeds the specified charge time Ts of the laser light source 20 described above (step S5).

Then, when the acquired movement required time Tm exceeds the specified charge time Ts (step S5: YES), the control device 70 maintains the switching signal to the switching element 30 in the OFF state (closed state) (step S7). ), The laser light source 20 is controlled so as to emit a dummy laser beam at a predetermined timing (step S9).
In principle, the control device 70 controls the laser light source 20 so as to emit the next laser beam for drilling after a predetermined charge time Ts from the completion of the emission of the laser beam for drilling immediately before. However, if the time required for the next movement by the deflector 50 exceeds the specified charge time Ts, the movement to the work position by the deflector 50 is not completed by the time when the laser beam for the next drilling is emitted. It is not possible to emit laser light to the planned work position of the object W.
Therefore, the control device 70 maintains the switching signal to the switching element 30 in the OFF state (closed state), and emits a dummy laser beam that does not reach the machining object W to the laser light source 20.
It is desirable that the timing at which the dummy laser beam is emitted is the timing at which the time (Tm-Ts) obtained by subtracting the specified charge time from the required travel time elapses from the emission of the laser beam immediately before.
Further, since the dummy laser beam D is not used for processing, its pulse width may be shorter than that of the laser beam for drilling.

Then, after the dummy laser beam is emitted, the control device 70 switches the switching signal to the switching element 30 to the ON state (open state) (step S11), and the specified charge time from the completion of the emission of the dummy laser beam D. The laser light source 20 is controlled so as to emit the laser beam for drilling after the elapse of Ts (step S13).

Here, the operation of emitting the dummy laser beam will be described in more detail with reference to the timing chart of FIG. FIG. 3 shows a control signal in which the control device 70 emits laser light to the laser light source 20. In the figure, the control signal is a rectangular pulse signal, and the laser is used during the period when the signal is in the ON state. Laser light is emitted from the light source 20.
In reality, the period during which the laser beam is emitted is sufficiently shorter than the charge time Ts at which the laser beam is not emitted, but in FIG. 3, for the sake of clarity, the period during which the laser beam is emitted is actually It is shown longer than.

In FIG. 3, the distance between the first laser beam R1 for drilling and the second laser beam R2 for drilling following the second laser beam R2 for drilling is short, and the cover of the second laser beam R2 for drilling is short. The time required for movement is set to be equal to or less than the specified charge time Ts by the deflector 50 to the processing position. Therefore, the second laser beam R2 for drilling is emitted after a predetermined charge time Ts without emitting the dummy laser beam D.
On the other hand, the second laser beam R2 for drilling and the third laser beam R3 for drilling following it have a long distance between the processing positions, and the third laser beam R3 for drilling The deflection device 50 to the work position makes the movement time Tm longer than the specified charge time Ts.
Therefore, the dummy laser beam D is emitted after waiting for the lapse of (movement required time Tm-specified charge time Ts) from the completion of emission of the second laser beam R2 for drilling. Strictly speaking, the dummy laser beam D should be emitted after waiting for the passage of (movement required time Tm-specified charge time Ts-dummy laser beam D pulse width), but the pulse of the dummy laser beam D should be emitted. The width is short enough that it does not need to be considered.
Further, after waiting for the lapse of the specified charge time Ts from the completion of the emission of the dummy laser beam D, the third laser beam R3 for drilling is emitted.
As a result, the first to third laser beams R1 to R3 for drilling have a specified charge time Ts from the completion of the immediately preceding laser beam emission, regardless of the length of time required to move to each processing position. Since the emission is performed after waiting for the progress of the above, it is possible to perform the drilling process in the object W to be processed while achieving uniform and stable output.
Further, by emitting the dummy laser beam D, the deflector 50 can move the third laser beam R3 for drilling to the work position in time, and appropriate drilling can be performed.

Further, in step S5 of FIG. 2, when the acquired movement required time is equal to or less than the specified charge time Ts, the control device 70 skips the processes of steps S7 and S9.
Then, the control device 70 switches the switching signal to the switching element 30 to the ON state (open state) (step S11), and receives the laser light for drilling immediately before (corresponding to the first laser light R1 in FIG. 3). The laser light source 20 is controlled so as to emit the laser beam for drilling (corresponding to the second laser beam R2 in FIG. 3) after the lapse of the specified charge time Ts from the completion of the emission (step S13).

This will be described with reference to the timing chart of FIG. FIG. 4A shows the operation timing of the deflector 50. The ON state indicates the state of moving to the work position, and the OFF state indicates the state of stopping. Further, FIG. 4B shows the emission timing of the laser beam for drilling the laser light source 20, the ON state indicates the state in which the laser light is emitted, and the OFF state indicates the state in which the laser light is stopped.
As shown in the figure, when the movement time Tm from the processed position of the first laser beam R1 for drilling to the processed position of the second laser beam R2 for drilling is short, the first for drilling The second laser beam R2 for drilling is emitted after the movement required time Tm has elapsed from the completion of the emission of the laser beam R1 and the specified charge time Ts has elapsed.

Next, the control device 70 determines from the processing pattern data stored in the storage unit 71 whether or not the drilling of all the work positions is completed (step S15).
Then, if it is not completed (step S15: NO), the process returns to step S1. In this case, it is also determined whether the next work position is within the movable range of the deflector 50, and if it is outside the range, the machining object W is also moved by the XY stage 60.
Further, when the drilling of all the positions to be machined is completed (step S15: YES), the control of the drilling is finished.

[Technical effect of laser processing equipment]
In the laser machining apparatus 10, the time between the second laser beam R2 for drilling and the third laser beam R3 for drilling is determined by the deflector 50 obtained from the data of the pattern in which the machined position of the hole is determined. It is regulated based on the travel time of.
Then, the control device 70 of the laser processing device 10 controls to emit the first laser beam R1 for drilling, the second laser beam R2 for drilling, and the third laser beam R3 for drilling. .. Further, the control device 70 has a second laser beam R2 for drilling and a third laser for drilling rather than the time between the first laser beam R1 for drilling and the second laser beam R2 for drilling. When the time between the light R3 and the light R3 is long, control is performed so that a dummy laser light D is emitted between the second laser light R2 for drilling and the third laser light R3 for drilling.
Therefore, when the distance from the processed position of the second laser beam R2 for drilling to the processed position of the third laser beam R3 for drilling is long and the movement time required Tm is long, the dummy laser beam D Is emitted, the time from the emission of the dummy laser beam D to the emission of the third laser beam R3 for drilling can be optimized, and the first to third laser beams R1 for drilling can be optimized. The output of the laser beam of R3 can be stabilized and made uniform, and the drilling quality can be improved.
Further, the time between the second laser beam R2 for drilling and the third laser beam R3 for drilling is based on the moving time of the deflector 50 obtained from the data of the pattern in which the processing position of the hole is determined. As in the conventional case, it is possible to reduce the unnecessary waiting time Tu (see FIG. 5) from the moving time of the deflector 50, and it is possible to reduce the delay in the machining speed caused by one dummy pulse. ..
For this reason, it is possible to significantly increase the processing speed for one processing object, particularly when the number of workpiece positions for one processing object W is large.

Further, in the control device 70, the time interval between the first laser beam R1 for drilling and the second laser beam R2 for drilling and the time interval between the dummy laser beam D and the third laser beam R3 for drilling are set. Since it is controlled so that they are aligned, it is possible to stabilize and equalize the output of the laser beams of the first to third laser beams R1 to R3 for drilling, and it is possible to further improve the drilling processing quality. It becomes.
In particular, the time interval between the first laser beam R1 for drilling and the second laser beam R2 for drilling and the time interval of the third laser beam R3 for drilling with the dummy laser beam D are both set. By setting the charge time in the pulse oscillation of the laser light source 20, a sufficient output of the laser light can be stably and uniformly obtained, and the drilling quality can be further improved.

Further, the control device 70 provides a dummy laser beam when the time interval between the second laser beam R2 for drilling and the third laser beam R3 for drilling exceeds the specified charge time Ts in the pulse oscillation of the laser light source. Control is performed so as to emit D. This makes it easy to maintain the time interval from the laser beam for drilling immediately before in the laser beam for drilling each time to the specified charge time. As a result, a sufficient output of the laser beam can be stably and uniformly obtained, the drilling quality can be further improved, and the machining speed by the dummy laser beam can be increased. It will be possible.

[Other]
The present invention is not limited to the above embodiments.
For example, as the laser light source 20, a laser medium other than those illustrated may be used as long as it performs pulse oscillation.
Further, the deflector 50 may use another optical device having the same function as the galvano scanner.

Further, in the deflector 50, although not particularly mentioned, it is also possible to use a biaxial galvano scanner. In that case, the movement time required for each of the two axes is acquired, the longer time of the acquired two-axis movement time is compared with the specified charge time Ts, and the dummy laser beam is emitted. The presence or absence should be decided.

Further, a case where the control device 70 performs a process of obtaining the required time for each movement from the processing pattern data is illustrated, but this process is performed by a processing device other than the control device 70, and the processing result is notified to the control device 70. May be. Alternatively, a processing device other than the control device 70 executes a process of obtaining the required time for each movement from the processing pattern data in advance, and stores the processing result in the storage unit 71 in advance. Then, the control device 70 may be configured to read the processing result (required time for each movement) stored in the storage unit 71 when executing the control of the drilling process.
Further, the processing device other than the control device 70 obtains the processing result (required time for each movement) in advance, and also determines whether or not the dummy laser beam is emitted each time. Then, the control device 70 notified of the determination result may be configured to execute the control of the drilling process. Alternatively, the determination result may be stored in the storage unit 71 in advance, and the control device 70 may execute the control of the drilling process based on the stored determination result.

Further, the hole formed by the laser processing apparatus 10 may be a through hole or a blind hole.

In addition, the details shown in the embodiment can be appropriately changed without departing from the spirit of the invention.

10 Laser processing device 20 Laser light source 30 Switching element 31 Beam damper 41 Folded mirror 42 fθ lens 50 Deflator 60 XY stage 70 Control device 71 Storage unit D Dummy laser light P1-P3 Pulse oscillation PD Dummy laser oscillation R1 No. 1 for drilling One laser beam R2 Second laser beam for drilling R3 Third laser beam for drilling
Th settling time
Tm travel time
Ts specified charge time
Tu Unnecessary waiting time W Machining object

Claims (2)

With a laser light source
With a deflector
A switching element that irradiates a dummy laser beam by switching the diffraction direction of the laser beam from the laser light source , and
A control device for controlling the laser light source, the deflector, and the switching element is provided.
The control device is
A first laser beam for drilling emitted from the laser light source, a second laser beam for drilling emitted from the laser light source, and a third laser beam for drilling emitted from the laser light source. While controlling the emission of
The time between the second laser beam for drilling and the third laser beam for drilling is greater than the time between the first laser beam for drilling and the second laser beam for drilling. If long, performs control so as to emit the dummy laser beam between the third laser beam for the boring and the second laser beam for the drilling,
The time between the second laser beam for drilling and the third laser beam for drilling is defined based on the moving time of the deflector obtained from the pattern that defines the position of the hole to be machined. Ori,
In the control device, the time interval between the first laser beam for drilling and the second laser beam for drilling, and the time interval between the dummy laser beam and the third laser beam for drilling are aligned. Control and
The time interval between the first laser beam for drilling and the second laser beam for drilling, and the time interval between the dummy laser beam and the third laser beam for drilling are all the laser. A laser processing device that is the charge time for pulse oscillation of a light source . The control device emits the dummy laser beam when the time interval between the second laser beam for drilling and the third laser beam for drilling exceeds the charge time in the pulse oscillation of the laser light source. The laser processing apparatus according to claim 1 , wherein the laser processing apparatus is controlled so as to perform the operation.

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