JP2019025505A - Laser beam machining apparatus and laser beam machining method - Google Patents

Abstract

To materialize high speed machining by shortening time up to irradiation of a workpiece with a laser pulse after stopping a galvanometer scanner, in laser beam machining in which laser oscillation is performed synchronously with stopping of the galvanometer scanner.SOLUTION: A laser beam machining apparatus is provided that comprises: a laser oscillator which oscillates a laser pulse; and a galvanometer scanner which is driven so that the laser pulse from the laser oscillator irradiates a working position complying with working data on a workpiece. The laser beam machining apparatus further comprises a laser oscillation control part which predicts a completion time point of positioning with the galvanometer scanner on the basis of a drive start time point every time the galvanometer scanner is driven, and outputs an oscillation command to the laser oscillator at a time point earlier than the predicted time point by a prescribed duration of time.SELECTED DRAWING: Figure 1

Description

The present invention relates to a laser processing apparatus and a laser processing method for making a hole in a printed circuit board using a laser, for example.

As a laser drilling method, as disclosed in Patent Document 1 (paragraphs 0011 to 0015), there is a method of irradiating a workpiece by performing laser oscillation in synchronization with the stop of the galvano scanner.
In this type of laser drilling apparatus, a response time for synchronization between the galvano scanner and other functional elements is required, which is a factor of reducing the processing speed.

FIG. 3 is a block diagram of a conventional laser drilling apparatus that irradiates a workpiece by performing laser oscillation in synchronization with the stop of the galvano scanner.
In FIG. 3, 1 is a printed circuit board to be processed placed on a table (not shown), 2 is a laser oscillator that oscillates a laser pulse L1, 3 is a laser pulse L1 output from the laser oscillator 2 and the direction of machining is not An acousto-optic modulator (hereinafter abbreviated as AOM) for branching in two directions, 4 is rotated so that a laser pulse L2 branched in the machining direction in AOM 3 is applied to the drilling position of printed circuit board 1 according to the machining data It is a driven galvano scanner. A damper 5 absorbs the laser pulse L3 branched in the non-machining direction in the AOM 3.

Reference numeral 6 denotes an overall control unit for controlling the operation of the entire apparatus, and inside thereof, a laser oscillation control for outputting a laser oscillation command signal S for commanding oscillation and attenuation of the laser pulse L1 in the laser oscillator 2 7, an AOM control unit 8 that outputs an AOM drive signal D for controlling the operation of the AOM 3, and a galvano control unit 9 that outputs a galvano control signal G for controlling the drive operation of the galvano scanner 4 are provided. . The laser oscillator 2 starts to attenuate the laser pulse L1 when the laser oscillation command signal S is turned off.
The overall control unit 6 has control functions other than those described here, and is also connected to blocks not shown. The overall control unit 6 is configured, for example, centering on a program-controlled processing device, and each component and connection line therein includes logical ones. A part of each component may be provided separately from the overall control unit 6.

FIG. 4 is a timing chart in the laser drilling apparatus of FIG. In FIG. 4, under the control of the overall control unit 6, the galvano operation control signal G is turned on, the galvano scanner 4 rotates, and when the galvano scanner 4 rotates to the target position and the positioning is completed, the galvano operation control signal G is turned off, and after time t1, a laser oscillation command signal S is output from the laser oscillation control unit 7 for a predetermined time to command the oscillation and attenuation of the laser pulse in the laser oscillator 2.
Then, the laser pulse L1 is output from the laser oscillator 2 after the time t2 after the laser oscillation command signal S is turned on, and the AOM drive signal D is turned on for a predetermined time after the time t3. From the AOM 3, the printed circuit board 1 is irradiated with a laser pulse L 2 branched in the processing direction via the galvano scanner 4. Thereafter, the galvano operation control signal G is turned on after a predetermined time t4 from the turning on of the laser oscillation command signal S, the galvano scanner 4 is rotated for irradiation to the next hole position, and the same is repeated thereafter.
In the above, the times t1 to t3 include processing / response times and signal propagation times between the functional elements in the related functional elements, respectively.

  In the conventional laser drilling apparatus, as can be seen from FIG. 4, a delay of time tb obtained by adding t1 and t3 until the workpiece is irradiated with the laser pulse L2 after the galvano scanner 4 completes positioning. This becomes a bottleneck in increasing the processing speed.

JP 2012-115883 A

Therefore, the present invention reduces the time from when the galvano scanner is stopped until the laser pulse is irradiated to the workpiece in laser processing in which laser oscillation is performed in synchronization with the stop of the galvano scanner. It aims to be realized.

  In order to solve the above-described problems, a typical laser processing apparatus disclosed in the present application includes a laser oscillator that oscillates a laser pulse, and a laser pulse from the laser oscillator at a processing position on a workpiece according to processing data. In a laser processing apparatus having a galvano scanner that is driven to irradiate, every time the galvano scanner is driven, a point in time when positioning with the galvano scanner is completed is predicted based on the driving start point, and the prediction A laser oscillation control unit that issues an oscillation command to the laser oscillator at a time earlier than the time by a predetermined time is provided.

  A typical laser processing method disclosed in the present application is a laser input to a galvano scanner that is driven so that a laser pulse oscillated by a laser oscillator is irradiated to a processing position on a workpiece according to processing data. In the processing method, every time the galvano scanner is driven, a time point at which positioning by the galvano scanner is completed is predicted based on the driving start time point, and the laser oscillator is sent to the laser oscillator at a time point earlier than the predicted time point. The oscillation command is issued.

It is a timing diagram of the laser drilling apparatus which becomes one Example of this invention. It is a block diagram of the laser drilling apparatus which becomes one Example of this invention. It is a block diagram of the conventional laser drilling apparatus. It is a timing diagram of the laser drilling apparatus of FIG.

  FIG. 2 is a block diagram of a laser drilling apparatus according to an embodiment of the present invention. The same reference numerals are given to the same components as those in FIG. 3, and each component and connection line are mainly those which are considered necessary for explaining the present embodiment, as in FIG. It does not show everything necessary as.

  In FIG. 2, reference numeral 10 denotes a laser oscillation control unit that outputs a laser oscillation command signal SP for commanding oscillation of the laser pulse L1 in the laser oscillator 2. Inside the laser oscillation control unit 10, the machining at the previous drilling position is finished, and every time the galvano operation control signal G is turned on and driven, information on the next drilling position given to the galvano scanner 4 is used. A galvano movement prediction unit 11 is provided for predicting the time when the positioning of the galvano scanner 4 is completed from the start of driving. The laser oscillation control unit 10 outputs the laser oscillation command signal SP at a time earlier by a predetermined time t5 from the positioning completion prediction time.

FIG. 1 is a timing chart in the laser drilling apparatus of FIG. The same symbols are attached to the same components as those in FIG.
In FIG. 1, when the processing at the previous drilling position is completed under the control of the overall control unit 6 and the galvano operation control signal G is turned on, the galvano movement prediction unit 10 determines the galvano scanner based on the drive start time T01. 4. Calculate the point in time when positioning of 4 is completed. Needless to say, this positioning completion prediction time includes a settling time for causing the galvano scanner 4 to completely match the target position. If this positioning completion prediction time is Tm, the laser oscillation control unit 10 determines from Tm. The laser oscillation command signal SP is output to the laser oscillator 2 at a time Tm-t5 that is earlier by a predetermined time t5.

The laser oscillator 2 outputs a laser pulse L1 after time t2 after the laser oscillation command signal SP is turned on, and the AOM drive signal D is turned on for a predetermined time after time t3, as in the conventional case. . From the AOM 3, the printed circuit board 1 is irradiated with a laser pulse L 2 branched in the processing direction via the galvano scanner 4. Thereafter, the galvano operation control signal G is turned on after a predetermined time t4 from the turning on of the laser oscillation command signal S, and the galvano scanner 4 is rotated for irradiation to the next hole position.

When the galvano operation control signal G is turned on for drilling the next position, the galvano movement prediction unit 10 calculates the time point when the positioning of the galvano scanner 4 is completed based on the drive start time T02. Assuming that this positioning completion predicted time is Tn, the laser oscillation control unit 10 outputs a laser oscillation command signal SP to the laser oscillator 2 at a time Tn−t5 that is earlier than Tn by a predetermined time t5. Thereafter, the same is repeated.

  According to the above embodiment, as can be seen from FIG. 1, there is only a delay of time ta from the completion of positioning by the galvano scanner 4 until the workpiece is irradiated with the laser pulse L2, and this time is shown in FIG. Since it is shorter than the time tb obtained by adding t1 and t3 in 4, the processing speed can be increased as compared with the conventional case.

  The predetermined time t5 is set to be smaller than the time t3 from when the laser oscillation command signal SP is turned on until the AOM drive signal D is turned on. Otherwise, the laser pulse L2 is output before the galvano scanner 4 completes positioning, resulting in malfunction.

  In the above embodiment, the embodiment in the case where the printed circuit board is punched has been described. However, the present invention is not limited to this, and can be provided for laser processing in which processing is sequentially performed at a plurality of locations on the workpiece.

1: printed circuit board, 2: laser oscillator, 3: AOM, 4: galvano scanner,
5: damper, 6: overall control unit, 8: AOM control unit, 9: galvano control unit,
10: Laser oscillation control unit, 11: Galvano movement prediction unit,
SP: laser oscillation command signal, G: galvano operation control signal, D: AOM drive signal,
L1 to L3: Laser pulse, T01, T02: Driving start time,
Tm, Tn: Positioning completion prediction point,

Claims (2)

  A laser processing apparatus comprising: a laser oscillator that oscillates a laser pulse; and a galvano scanner that is driven so that the laser pulse from the laser oscillator is irradiated to a processing position on a workpiece according to processing data. Each time the scanner is driven, a laser that predicts a time when positioning by the galvano scanner is completed based on the driving start time and issues an oscillation command to the laser oscillator at a time earlier than the predicted time by a predetermined time A laser processing apparatus comprising an oscillation control unit. In a laser processing method in which a laser pulse oscillated by a laser oscillator is input to a galvano scanner that is driven so as to irradiate a processing position on a workpiece according to processing data, each time the galvano scanner is driven, A laser processing method characterized by predicting a time point at which positioning by the galvano scanner is completed based on a driving start time point and issuing an oscillation command to the laser oscillator at a time point earlier than the predicted time point.