JP2007175735A - Laser beam machining device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser beam machining device previously preventing a laser beam, which is emitted from a laser beam source, from being carelessly emitted outside. <P>SOLUTION: The laser beam machining device is provided with: a laser beam source 11 for emitting a laser beam; a control circuit 12 for controlling the laser beam source; a convergent lens 16 for converging the laser beam on a workpiece W; a shutter 17, which is movable on an optical path L of the laser beam between a passing position, where the laser beam is passed, and a blocking position, where the laser beam is blocked; and a shutter driving device 18 for driving the shutter to move between the passing position and the blocking position. The control circuit 12 detects shift time based on detection signals from a passing detection device 19 and a blocking detection device 20 when the shutter is moved from one of the passing position and the blocking position to the other position, determines abnormality based on the shift time and reference time set previously, and drives an information device 21 to inform the abnormality of the shutter. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a laser processing apparatus including a shutter for preventing inadvertent emission of laser light from a laser light source to the outside.

Conventionally, as this type of laser processing apparatus, for example, the one described in Patent Document 1 is known. The shielding device (12) of this laser processing device drives the rotary solenoid (15) to move the shutter (between the passage position where the laser light from the laser light source passes and the shielding position where the laser light is blocked). 13) is configured to be moved. The laser processing apparatus also includes a pair of optical sensors (22a, 22b) for detecting that the shutter is in the above-described passing position or blocking position, and the detection results of these optical sensors and the emission of laser light. The shutter function abnormality is determined based on the command state.
Japanese Examined Patent Publication No. 7-34062 (Fig. 3-4)

  By the way, in this laser processing apparatus, the movement of the shutter to the passing position or the blocking position becomes insufficient due to, for example, bearing wear of the rotary solenoid or aging of other functional parts, and the opening or closing of the laser light path is completed. There is a possibility that a fully open state or a completely closed state is not reached. On the other hand, since only the detection of the direct passing position or the blocking position by the pair of optical sensors is not judged as abnormal unless the shutter function is actually malfunctioned, the response is delayed.

  For example, in the case of an apparatus having an internal power measurement function for measuring laser power with the shutter closed, when laser light is emitted for laser power measurement in a state where the fully closed state is incomplete, the laser light is There is a possibility of leaking outside. Alternatively, when the laser beam is emitted to the workpiece in a state where the fully open state is incomplete, the laser beam is not only blocked by the shutter but also reflected or diffracted by the shutter. The part may be irradiated.

  The objective of this invention is providing the laser processing apparatus which can prevent in advance that the laser beam from a laser light source is inadvertently emitted outside.

  In order to solve the above problems, the invention described in claim 1 is directed to a laser light source that emits laser light, a control unit that controls the laser light source, and laser light from the laser light source on a workpiece. In a laser processing apparatus comprising a converging lens for condensing, a passage position for passing the laser light from the laser light source to the object to be processed on the optical path of the laser light from the laser light source and blocking for blocking the laser light A shutter that is movable between a position, a shutter driving unit that drives the shutter to move between the passing position and the blocking position, and the shutter that is driven to move by the shutter driving unit includes the passing position and A transition time detecting means for detecting a transition time when moving from either one of the blocking positions to the other; the transition time and the preset time; Based on the reference time to determine the abnormal, and summarized in that and a shutter abnormality detecting means for informing the shutter abnormality.

  According to this configuration, the transition time when the shutter moves from one of the passing position and the blocking position to either one is detected by the transition time detecting means. This transition time varies with, for example, aging deterioration of the shutter driving means, and is a time that can be used to predict the occurrence of a state where the movement of the shutter to the passing position or the blocking position may be insufficient. Then, the shutter abnormality detection means determines an abnormality based on the detected transition time and a preset reference time, and notifies the shutter abnormality. Thus, using the transition time, the occurrence of a state where the movement of the shutter to the passing position or the blocking position may be insufficient is predicted, and an abnormality is determined and a shutter abnormality is notified. Therefore, it is possible to quickly respond, for example, maintenance and inspection. Therefore, it is possible to prevent the laser light from the laser light source from being accidentally emitted outside.

  According to a second aspect of the present invention, in the laser processing apparatus according to the first aspect, the transition time detecting means includes passage detection means for detecting that the shutter is in the passage position, and the shutter is in the blocking position. And detecting the transition time based on the passage detection signal of the passage detection means and the interruption detection signal of the interruption detection means.

  According to this configuration, the passage detection means and the interruption detection means detect that the shutter is in the passage position and the interruption position, respectively, and the passage detection signal of the passage detection means and the interruption detection means are interrupted. Since the transition time is detected based on the detection signal, the detection accuracy of the transition time can be improved.

  According to a third aspect of the present invention, in the laser processing apparatus according to the first or second aspect, the shutter driving means is an electric urging means for generating an electric urging force, and the electric urging force is reversed. A mechanical urging means for generating a directional mechanical urging force, and when the electric urging means is in a non-energized state, the mechanical urging force moves the shutter from the passing position to the blocking position. And the shutter is held against the mechanical biasing force by the electrical biasing force when the electrical biasing means is energized when the shutter is held in the blocking position by the mechanical biasing force. The gist of the invention is that the shutter is moved to the passing position and the shutter is held at the passing position with a predetermined energization amount for the electrical biasing means.

  According to this configuration, for example, when energization to the electrical urging means becomes impossible, the shutter is moved from the passing position to the blocking position by the mechanical urging force, and is moved to the blocking position. Therefore, at least laser light from the laser light source can be prevented from being inadvertently emitted to the outside. Further, by setting a predetermined energization amount for the electrical urging means when the shutter is held at the passing position to a minimum energization amount necessary for the holding, power saving is achieved. be able to.

  According to a fourth aspect of the present invention, in the laser processing apparatus according to the third aspect, the transition time detecting means moves the shutter from the blocking position to the passing position in the energized state of the electrical urging means. The shutter opening time when moving is detected as the transition time, and when the shutter opening time is greater than the reference time, the shutter abnormality detecting means determines a drive abnormality of the electrical biasing means, and the shutter The gist is to notify the abnormality.

  According to this configuration, the transition time detecting means detects the shutter open time as the transition time when the shutter moves from the blocking position to the passing position in the energized state of the electrical biasing means. Is done. This shutter opening time tends to increase due to a decrease in driving force accompanying aged deterioration of the electrical biasing means. When the shutter abnormality detection means informs the shutter abnormality when the shutter opening time is larger than the reference time, the abnormality of the driving of the electrical biasing means is determined and the shutter abnormality is notified, and the shutter abnormality is notified. It is possible to speed up identification (cause investigation) of abnormal parts.

  According to a fifth aspect of the present invention, in the laser processing apparatus according to the third aspect, the transition time detecting means is configured such that the shutter is moved from the passing position to the blocking position in the non-energized state of the electrical urging means. A shutter closing time when moving to the shift time is detected as the transition time, and the shutter abnormality detecting means determines a driving abnormality of the mechanical biasing means when the shutter closing time is larger than the reference time, The gist is to notify the shutter abnormality.

  According to the configuration, the shutter is moved from the passing position to the blocking position by the mechanical urging force of the mechanical urging means in the non-energized state of the electric urging means by the transition time detecting means. The shutter closing time when moving is detected as the transition time. The shutter closing time tends to increase due to a decrease in the urging force accompanying the aging deterioration of the mechanical urging means. When the shutter abnormality detection means informs the shutter abnormality when the shutter closing time is greater than the reference time, the mechanical abnormality is determined to be abnormal, and the shutter abnormality is notified. It is possible to speed up identification (cause investigation) of abnormal parts.

  A sixth aspect of the present invention is the laser processing apparatus according to any one of the first to fifth aspects, wherein the transition time detecting means moves the shutter from the blocking position to the passing position. The shutter opening time is detected as the transition time, and the shutter abnormality detecting means determines an abnormality based on the shutter opening time and the reference time, notifies the shutter abnormality, and the transition time detecting means Detects the shutter closing time when the shutter moves from the passing position to the blocking position as the transition time, and the shutter abnormality detecting means determines an abnormality based on the shutter closing time and the reference time. Informing the shutter abnormality, the reference time related to the abnormality determination based on the shutter opening time, and the abnormality determination based on the shutter closing time. That the reference period and is summarized in that it is set to different times.

  According to the same configuration, the reference time related to the abnormality determination based on the shutter opening time and the reference time related to the abnormality determination based on the shutter closing time are individually set at different times, An abnormality reflecting each movement characteristic between the blocking position and the passing position can be determined.

  A seventh aspect of the present invention is the laser processing apparatus according to any one of the first to sixth aspects, wherein the reference time is set to a unique value for each laser processing apparatus. And

According to this configuration, since the reference time is set to a unique value for each laser processing apparatus, it is possible to determine an abnormality reflecting individual differences among the laser processing apparatuses.
According to an eighth aspect of the present invention, in the laser processing apparatus according to any one of the first to seventh aspects, the laser light source is forcibly activated when an abnormality is determined by the shutter abnormality detecting means. The gist is to stop.

  According to this configuration, when an abnormality is determined by the shutter abnormality detecting means, the laser light source is forcibly stopped, so that the laser light from the laser light source is promptly emitted to the outside. Can be prevented.

  The invention according to claim 9 is the laser processing apparatus according to any one of claims 1 to 8, wherein the reference time is obtained by subtracting a predetermined time from a time corresponding to a shutter life, or The gist is that the spare time is set to a predetermined ratio.

  According to this configuration, since the preliminary time is set as the reference time, it is possible to determine an abnormality with a strict shutter life, and the laser light from the laser light source is inadvertently emitted to the outside. This can be prevented more reliably.

  In the first to ninth aspects of the present invention, it is possible to prevent the laser light from the laser light source from being accidentally emitted outside.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.
FIG. 1 shows a configuration block diagram of a laser processing apparatus 10 of the present embodiment. This laser processing apparatus 10 is for marking characters, symbols, figures, etc. on the surface of the workpiece W.

  The laser light source 11 of the laser processing apparatus 10 is composed of a laser oscillator (for example, a YAG laser), emits a processing laser beam, and its oscillation is controlled by a control circuit 12 constituting a control means.

The beam expander 13 disposed at the subsequent stage of the laser light source 11 expands the beam diameter of the laser light emitted from the laser light source 11.
The optical scanning mechanism 14 disposed at the subsequent stage of the beam expander 13 is constituted by, for example, a galvano mirror composed of a pair of X-axis mirror and Y-axis mirror, and the beam diameter is expanded by the beam expander 13. The laser beam is reflected to change the irradiation direction. In the optical scanning mechanism 14, the rotation angle of each mirror is controlled by driving control of the driving device 15 by the control circuit 12. By rotating each mirror, the laser beam is two-dimensionally scanned based on characters, symbols, figures, etc. to be marked.

  A converging lens (fθ lens) 16 arranged at the rear stage of the optical scanning mechanism 14 collects the laser beam whose beam diameter is once enlarged by the beam expander 13 until a predetermined spot diameter is obtained on the surface of the workpiece W. Light up and increase energy density suitable for marking. And the marking process is given to the surface of the workpiece W by this laser beam.

  On the optical path L of the laser beam reflected by the optical scanning mechanism 14, the shutter 17 made of a metal plate disposed on the front side of the focusing lens 16 is directed from the laser light source 11 (optical scanning mechanism 14) to the workpiece W. It is provided so as to be movable between a blocking position for blocking the laser beam (shown by a solid line) and a passing position for passing the laser beam (shown by a broken line). When the shutter 17 is disposed at the blocking position, the laser light traveling from the optical scanning mechanism 14 toward the focusing lens 16 is blocked by the shutter 17 and does not reach the focusing lens 16 (and the workpiece W). On the other hand, when the shutter 17 is disposed at the passing position, the laser light from the optical scanning mechanism 14 can reach the focusing lens 16 (and the workpiece W). The shutter 17 is moved between the passing position and the blocking position described above by driving control of the shutter driving device 18 as shutter driving means by the control circuit 12. The shutter 17 and the shutter driving device 18 constitute a shutter mechanism.

  The state where the shutter 17 is in the passing position is detected by a passage detecting device 19 which is a photo interrupter and serves as a passage detecting means constituting a transition time detecting means. The passage detection device 19 outputs to the control circuit 12 a passage detection signal that is turned on when the shutter 17 is in the passage position and turned off when the shutter 17 is removed from the passage position. On the other hand, the state in which the shutter 17 is in the cutoff position is detected by the cutoff detection device 20 as a cutoff detection means that constitutes the transition time detection means, which is a photo interrupter. The interruption detection device 20 outputs an interruption detection signal to the control circuit 12 that is turned on when the shutter 17 is in the interruption position and turned off when the shutter 17 is removed from the interruption position.

  The control circuit 12 drives and controls the laser light source 11 and the like based on detection signals from the passage detection device 19 and the interruption detection device 20. Thus, for example, when the laser light source 11 is stopped, the shutter 17 is disposed at the blocking position, the optical path L of the laser light is closed, and the laser light is prevented from being inadvertently emitted to the outside. Further, the control circuit 12 determines an abnormality based on the passage detection signal and the interruption detection signal.

The notification device 21 that is driven and controlled by the control circuit 12 includes, for example, an indicator lamp, and is driven to be lit when an abnormality is determined.
The control circuit 12 is electrically connected to an operation unit 30 that outputs processing information (for example, information on characters, figures, etc. to be marked) for the workpiece W to the control circuit 12.

  In the laser processing device 10 configured as described above, the control circuit 12 drives the shutter driving device 18 to move the shutter 17 from the blocking position to the passing position when marking the workpiece W. Let Then, the control circuit 12 detects that the shutter 17 is in the passing position based on the passage detection signal, that is, that the optical path L of the laser light is opened, and then drives the laser light source 11 to emit the laser light. . Further, the control circuit 12 drives the driving device 15 to perform angle control of the two mirrors constituting the optical scanning mechanism 14. That is, the control circuit 12 scans the laser beam two-dimensionally according to the processing information output from the operation unit 30 and performs marking of a predetermined shape on the surface of the processing target W. At this time, it goes without saying that the laser light emitted from the laser light source 11 reaches the workpiece W without being blocked by the shutter 17.

  On the other hand, when finishing the marking process on the workpiece W, the control circuit 12 stops driving the laser light source 11 and then drives the shutter driving device 18 to move the shutter 17 from the passing position to the blocking position. Let Therefore, it is possible to prevent the laser light from being inadvertently emitted outside while the laser light source 11 is stopped. The control circuit 12 detects that the shutter 17 is in the blocking position, that is, that the optical path L of the laser beam is closed based on the blocking detection signal.

  Next, the structure of the shutter 17 and the shutter driving device 18 of the present embodiment will be described based on the schematic diagram shown in FIG. As shown in the figure, a shutter 17 made of a metal plate is attached to a shaft of a rotary solenoid 22 as an electrical urging means constituting a shutter driving device 18 and is attached to the rotary solenoid 22 by a control circuit 12. It is rotationally driven around the rotation axis O by energization. When the rotary solenoid 22 is not energized, the shutter 17 is held at a predetermined reference angular position by the mechanical biasing force of the return spring 23 as the mechanical biasing means constituting the shutter driving device 18 (FIG. 2). (See (a)). This reference angular position corresponds to a blocking position where the shutter 17 closes the optical path L of the laser beam. Further, the shutter 17 forms an extending piece 17a extending at a predetermined angle with respect to the longitudinal direction and extending in the radial direction about the rotation axis O. When the shutter 17 is in the blocking position (reference angle position), the extending piece 17a blocks the optical axis of the blocking detection device 20 made of a photo interrupter and opens the optical axis of the passage detection device 19. Therefore, at this time, the interruption detection signal output from the interruption detection device 20 is turned on, and the passage detection signal output from the passage detection device 19 is turned off.

  On the other hand, in the energized state of the rotary solenoid 22, the shutter 17 is rotated to a predetermined angular position in the clockwise direction of the figure against the mechanical biasing force of the return spring 23, and at the angular position with a predetermined energization amount. It is held (see FIG. 2B). That is, the driving force as an electrical urging force generated by the rotary solenoid 22 is in the opposite direction to the mechanical urging force generated by the return spring 23. This angular position corresponds to a passing position where the shutter 17 opens the optical path L of the laser light. At this time, the extension piece 17 a blocks the optical axis of the passage detection device 19 and opens the optical axis of the block detection device 20. Therefore, at this time, the passage detection signal output from the passage detection device 19 is turned on, and the interruption detection signal output from the interruption detection device 20 is turned off. The predetermined energization amount for the rotary solenoid 22 is the minimum energization amount necessary for holding the shutter 17 at a predetermined angular position (passing position) against the mechanical biasing force of the return spring 23. For example, it is formed by a pulse current.

  When the rotary solenoid 22 is again de-energized, the shutter 17 is rotated and returned to the reference angular position (blocking position) by the mechanical biasing force of the return spring 23 (see FIG. 2A).

  Here, an abnormality detection mode by the control circuit 12 will be described. FIG. 3 is a time chart showing the blocking detection signal S1 and the passing detection signal S2 when the shutter 17 moves from the blocking position to the passing position. FIG. 4 shows the shutter 17 moving from the passing position to the blocking position. It is a time chart which shows the interruption | blocking detection signal S1 and the passage detection signal S2 at the time.

  As shown in FIG. 3, when the shutter 17 moves from the blocking position to the passing position, the extension piece 17 a opens the optical axis of the blocking detection device 20 with rotation about the rotation axis O, The optical axis of the passage detection device 19 is blocked. Thereby, after the interruption detection signal S1 is switched from the on state to the off state, the passage detection signal S2 is switched from the off state to the on state. The control circuit 12 constituting the transition time detecting means has a built-in time from the time when the shutoff detection signal S1 is switched to the off state to the time when the passage detection signal S2 is switched on as the shutter opening time t1 as the transition time. Clock with a timer. The shutter opening time t1 has a tendency to increase due to a decrease in driving force accompanying aged deterioration of the rotary solenoid 22 (for example, bearing wear), and has a correlation with the shutter life. Further, the control circuit 12 stores the shutter opening time t1 measured at the shipping stage in advance in the internal memory as the shipping shutter opening time Tb1, and sets a predetermined reference time Ts1 based on the shipping shutter opening time Tb1. Store in advance in the internal memory. The reference time Ts1 is larger than the shutter opening time Tb1 at the time of shipment, and is set to a suitable value for determining the shutter life (aging of the rotary solenoid 22) based on the shutter opening time t1. The reference time Ts1 is set as a safety preparatory time by subtracting a predetermined time from a time corresponding to a strict shutter life (or reducing it to a predetermined ratio).

  For example, when the measured shutter opening time t1 is within the range of the reference time Ts1, the control circuit 12 constituting the shutter abnormality detecting means determines that the shutter is normal, assuming that the aged deterioration is within a normal range. . On the other hand, when the measured shutter opening time t1 exceeds the range of the reference time Ts1, the control circuit 12 determines that the shutter is in the stage of the shutter life (abnormal driving of the rotary solenoid 22). At this time, the control circuit 12 notifies the shutter abnormality by lighting the notification device 21. At the same time, the control circuit 12 forcibly inhibits and stops the oscillation of the laser light source 11.

  As shown in FIG. 4, when the shutter 17 moves from the passing position to the blocking position, the extension piece 17a opens the optical axis of the passage detecting device 19 with the rotation about the rotation axis O. Thereafter, the optical axis of the interruption detection device 20 is interrupted. Thereby, after the passage detection signal S2 is switched from the on state to the off state, the blocking detection signal S1 is switched from the off state to the on state. The control circuit 12 constituting the transition time detecting means has a built-in time from the time when the passage detection signal S2 is switched to the OFF state to the time when the cutoff detection signal S1 is switched to the ON state as a shutter closing time t2 as a transition time. Clock with a timer. The shutter closing time t2 shows a tendency to increase due to a decrease in the urging force accompanying the aging of the return spring 23 (for example, material fatigue), and has a correlation with the shutter life. Further, the control circuit 12 previously stores the shutter closing time t2 timed at the shipping stage in its internal memory as a shipping shutter closing time Tb2, and a predetermined reference time Ts2 based on the shipping shutter closing time Tb2. Store in advance in the internal memory. This reference time Ts2 is larger than the shutter closing time Tb2 at the time of shipment, and is set to a suitable value for determining the shutter life (aging of the return spring 23) based on the shutter closing time t2. The reference time Ts2 is set as a safety reserve time by subtracting the predetermined time from the time corresponding to the strict shutter life (or by reducing the predetermined time).

  For example, when the counted shutter closing time t2 is within the range of the reference time Ts2, the control circuit 12 constituting the shutter abnormality detecting means determines that the shutter is normal, assuming that the aging deterioration is within the normal range. . On the other hand, when the measured shutter closing time t2 exceeds the range of the reference time Ts2, the control circuit 12 determines that there is an abnormality (driving abnormality of the return spring 23) as being in the stage of the shutter life. At this time, the control circuit 12 notifies the shutter abnormality by lighting the notification device 21. At the same time, the control circuit 12 forcibly inhibits and stops the oscillation of the laser light source 11.

As described above in detail, according to the present embodiment, the following effects can be obtained.
(1) In this embodiment, the control circuit 12 detects the transition time (shutter opening time t1) when the shutter 17 moves from the blocking position to the passing position. Further, the control circuit 12 detects a transition time (shutter closing time t2) when the shutter 17 moves from the passing position to the blocking position. Each transition time fluctuates due to deterioration of the shutter drive device 18 (rotary solenoid 22, return spring 23) over time, and the like (shutter life) in a state where the movement of the shutter 17 to the passing position or the blocking position can be insufficient. This is the time that can be used to predict the occurrence. Then, the control circuit 12 determines an abnormality based on the detected transition time (shutter opening time t1, shutter closing time t2) and preset reference times Ts1, Ts2, and notifies the shutter abnormality. In this manner, by using the transition time and predicting the occurrence of a state where the movement of the shutter 17 to the passing position or the blocking position may be insufficient, the abnormality is determined and the shutter abnormality is notified. For example, quick response such as maintenance and inspection becomes possible. Therefore, it is possible to prevent the laser light from the laser light source 11 from being accidentally emitted outside. Alternatively, it is possible to prevent in advance that the laser light from the laser light source 11 to the workpiece W is emitted to the shutter 17 and the laser light is reflected or diffracted by the shutter 17 and irradiated to an unintended portion. Can do.

  (2) In this embodiment, since the passage detection device 19 and the interruption detection device 20 detect that the shutter 17 is in the passage position and the interruption position, respectively, the transition time (shutter opening time t1, shutter closing time t2). Detection accuracy can be improved.

  (3) In this embodiment, when the energization of the rotary solenoid 22 of the shutter drive device 18 becomes impossible due to, for example, an electrical failure, the shutter 17 is blocked from the passing position by the mechanical biasing force of the return spring 23. Since it moves to the position and is held at the blocking position, at least laser light from the laser light source 11 can be prevented from being inadvertently emitted to the outside.

  (4) In this embodiment, the energization amount (predetermined energization amount) to the rotary solenoid 22 when the shutter 17 is held at the passing position is set to the minimum energization amount necessary for the holding, thereby saving Electricity can be achieved.

  (5) In this embodiment, the control circuit 12 detects the shutter opening time t1 when the shutter 17 moves from the blocking position to the passing position in the energized state of the rotary solenoid 22 of the shutter driving device 18 as the transition time. The The shutter opening time t1 tends to increase due to a decrease in driving force accompanying the deterioration of the rotary solenoid 22 over time. When the shutter opening time t1 is greater than the reference time Ts1, the control circuit 12 determines that the rotary solenoid 22 is operating abnormally, and notifies the shutter abnormality, thereby identifying the abnormal location when the shutter abnormality is notified. (Cause investigation) can be speeded up.

  (6) In this embodiment, when the control circuit 12 causes the mechanical force of the return spring 23 to move the shutter 17 from the passing position to the blocking position when the rotary solenoid 22 of the shutter driving device 18 is not energized. The shutter closing time t2 is detected as the transition time. The shutter closing time t2 tends to increase due to a decrease in the urging force accompanying the aging deterioration of the return spring 23. When the shutter closing time t2 is greater than the reference time Ts2, the control circuit 12 determines that the return spring 23 is operating abnormally, and notifies the shutter abnormality, thereby identifying the abnormal location when the shutter abnormality is notified. (Cause investigation) can be speeded up.

  (7) In this embodiment, since the passage detection device 19 and the interruption detection device 20 detect that the shutter 17 is in the passage position and the interruption position, respectively, for example, either the passage detection device 19 or the interruption detection device 20 The detection accuracy can be improved compared to the case where one of the passing position and the blocking position is detected by one, and that the other position is detected (estimated) by the anti-logical logic. Can be improved. Then, it is possible to more reliably detect the fully open state or the fully closed state in which the opening or closing of the optical path L by the shutter 17 is completed. Accordingly, the movement of the shutter 17 to the passing position or the blocking position remains insufficient, and the laser light from the laser light source 11 is inadvertently emitted to the outside, or the laser light source 11 is directed to the workpiece W. It is possible to more reliably prevent the laser light from being emitted to the shutter 17 and being reflected or diffracted by the shutter 17 to irradiate an unintended portion.

(8) In the present embodiment, a safer laser processing apparatus 10 that can monitor the shutter life can be realized.
(9) In this embodiment, the reference time Ts1 related to the abnormality determination based on the shutter opening time t1 and the reference time Ts2 related to the abnormality determination based on the shutter closing time t2 are individually set at different times. By doing so, it is possible to determine an abnormality reflecting each movement characteristic between the blocking position and the passing position, for example, the driving characteristic (electric characteristic, mechanical characteristic) of the rotary solenoid 22 or the return spring 23.

  (10) In the present embodiment, when the control circuit 12 determines that an abnormality has occurred, the laser light source 11 is forcibly stopped to inadvertently emit the laser light from the laser light source 11 to the outside. Can be prevented promptly.

  (11) In the present embodiment, since the safety preliminary time is set as the reference times Ts1 and Ts2, it is possible to determine an abnormality with a margin in the strict shutter life, and the laser light from the laser light source 11 Can be reliably prevented from being accidentally emitted to the outside. Alternatively, it is possible to more surely prevent the laser light from the laser light source 11 to the workpiece W from being emitted to the shutter 17 and the laser light reflected or diffracted by the shutter 17 to irradiate an unintended portion. it can.

In addition, you may change the said embodiment as follows.
In the above embodiment, the shutter 17 may be driven (rotated) by an electric motor instead of the rotary solenoid 22.

  In the embodiment, the shutter may open and close the optical path L by linear motion. In this case, the shutter may be driven by a linear solenoid instead of the rotary solenoid 22. In the non-energized state of the linear solenoid, the shutter is linearly moved from the passing position to the blocking position by the mechanical biasing force of the return spring as the mechanical biasing means, and the shutter is moved to the blocking position by the mechanical biasing force. In the energized state of the linear solenoid, the shutter may be linearly moved from the blocking position to the passing position against the mechanical biasing force, and the shutter may be held at the passing position with a predetermined energizing amount.

  In the embodiment, for example, when an angle sensor (for example, a rotary encoder) for detecting the rotation angle of the shaft of the rotary solenoid 22 is provided, the position of the shutter 17 (passing position, The blocking position may be detected.

  In the embodiment, the transition time (shutter opening time t1, shutter closing time t2) is not necessarily determined from the position of the shutter 17 (passing position, blocking position) based on the on / off state of the passage detection device 19 and the interruption detection device 20. There is no need to detect. For example, when the energization of the rotary solenoid 22 is started by the control circuit 12 as the shutter opening time t1, the energization of the rotary solenoid 22 is moved to the passing position against the mechanical biasing force of the return spring 23. You may employ | adopt the time until it changes to the minimum energization amount (predetermined energization amount) required in order to hold | maintain, ie, the time of an electric current change.

  In the embodiment, the reference times Ts1 and Ts2 may be set as unique values (time) for each laser processing apparatus 10. In this case, an abnormality reflecting individual differences of the laser processing apparatus 10 is determined.

  In the above-described embodiment, the movement / holding from the passing position of the shutter 17 to the blocking position may be performed by energizing the rotary solenoid 22. Alternatively, the movement and holding of the shutter 17 from the passing position to the blocking position may be performed by the action of gravity.

-In the said embodiment, a speaker or a buzzer may be employ | adopted as the alerting | reporting apparatus 21, and a warning sound may be generated by the alerting | reporting apparatus 21 at the time of abnormality determination.
The notification mode of the shutter abnormality by the notification device 21 may be changed between the abnormality determination based on the shutter opening time t1 and the abnormality determination based on the shutter closing time t2. For example, in the case of the notification device 21 composed of a single indicator lamp, the blinking pattern may be changed. Alternatively, an indicator lamp that is turned on when an abnormality is determined based on the shutter opening time t1 and when an abnormality is determined based on the shutter closing time t2 may be provided individually. Moreover, in the case of the alerting | reporting apparatus 21 which consists of a speaker or a buzzer, you may change the audio | voice pattern. By doing so, the cause of the abnormality can be easily recognized by an operator or the like.

  In the above-described embodiment, the storage of the shipping shutter opening time Tb1 and the shipping shutter closing time Tb2 by the control circuit 12 may be performed by measuring the shutter opening time t1 and the shutter closing time t2 immediately after the manufacturing is completed. Alternatively, the shipping shutter opening time Tb1 and the shipping shutter closing time Tb2 by the control circuit 12 may be stored by shifting to a detection mode for measuring the shutter opening time t1 and the shutter closing time t2 at the time of initial use by the user. Good. Alternatively, the storage of the shipping shutter opening time Tb1 and the shipping shutter closing time Tb2 by the control circuit 12 is shifted to a mode for measuring the shutter opening time t1 and the shutter closing time t2 when the user appropriately operates the operation unit 30. You may go. Then, the reference times Ts1 and Ts2 may be set and stored according to the calculation formulas appropriately based on the timing and storage of the shipping shutter opening time Tb1 and the shipping shutter closing time Tb2 in any manner. Good. It should be noted that when the shutter opening time t1 and the shutter closing time t2 are measured when setting and storing the reference times Ts1 and Ts2, it is preferable that the oscillation of the laser light source 11 is prohibited and stopped.

  In the above embodiment, the shutter 17 may be disposed between the beam expander 13 and the optical scanning mechanism 14 as long as it is on the optical path of the laser light. In this case, the shutter 17 only needs to block the laser light before the irradiation direction is changed by the optical scanning mechanism 14, and thus can be further downsized. The shutter 17 may be disposed between the laser light source 11 and the beam expander 13. In this case, the shutter 17 only needs to block the laser light before the beam diameter is expanded by the beam expander 13, and thus can be further reduced in size.

  -In the said embodiment, you may employ | adopt photoelectric switches other than a photo interrupter as the passage detection apparatus 19 or the interruption | blocking detection apparatus 20. FIG. Or you may employ | adopt a proximity sensor as the passage detection apparatus 19 or the interruption | blocking detection apparatus 20. FIG.

1 is a configuration block diagram of a laser processing apparatus according to an embodiment. (A) and (b) are schematic diagrams showing a shutter and the like. The time chart which shows the operation | movement of the embodiment. The time chart which shows the operation | movement of the embodiment.

Explanation of symbols

  L ... optical path, W ... workpiece, 10 ... laser processing apparatus, 11 ... laser light source, 12 ... control means, transition time detection means and shutter abnormality detection means, 16 ... focusing lens, 17 ... shutter, DESCRIPTION OF SYMBOLS 18 ... Shutter drive device as shutter drive means, 19 ... Pass detection device as passage detection means constituting transition time detection means, 20 ... Interrupt detection device as interrupt detection means constituting transition time detection means, 21 ... Shutter An alarm device constituting an abnormality detecting means, 22... A rotary solenoid as an electrical urging means, 23... A return spring as a mechanical urging means.

Claims (9)

In a laser processing apparatus comprising: a laser light source that emits laser light; a control unit that controls the laser light source; and a focusing lens that condenses the laser light from the laser light source onto an object to be processed.
A shutter movable between a passing position for passing the laser light from the laser light source to the workpiece and a blocking position for blocking the laser light on an optical path of the laser light from the laser light source;
Shutter driving means for driving the shutter to move between the passing position and the blocking position;
A transition time detecting means for detecting a transition time when the shutter driven to move by the shutter driving means moves from one of the passing position and the blocking position to the other; and
A laser processing apparatus comprising: a shutter abnormality detecting unit that determines abnormality based on the transition time and a preset reference time and notifies the shutter abnormality. In the laser processing apparatus of Claim 1,
The transition time detecting means includes
Passage detection means for detecting that the shutter is in the passage position;
An interruption detection means for detecting that the shutter is in the interruption position;
The laser processing apparatus, wherein the transition time is detected based on a passage detection signal of the passage detection means and a cutoff detection signal of the cutoff detection means. In the laser processing apparatus according to claim 1 or 2,
The shutter driving means includes
Electrical biasing means for generating electrical biasing force;
Mechanical urging means for generating a mechanical urging force opposite to the electrical urging force;
When the electrical biasing means is in a non-energized state, the mechanical biasing force moves the shutter from the passing position to the blocking position, and the mechanical biasing force holds the shutter at the blocking position;
When the electrical urging means is energized, the electrical urging force moves the shutter from the blocking position to the passing position against the mechanical urging force, and a predetermined amount for the electric urging means. The laser processing apparatus is characterized in that the shutter is held at the passing position with an energization amount of. In the laser processing apparatus of Claim 3,
The transition time detecting means detects, as the transition time, a shutter opening time when the shutter moves from the blocking position to the passing position in the energized state of the electrical biasing means,
The laser processing apparatus according to claim 1, wherein the shutter abnormality detection unit determines a drive abnormality of the electrical biasing unit and notifies the shutter abnormality when the shutter opening time is larger than the reference time. In the laser processing apparatus of Claim 3,
The transition time detection means detects, as the transition time, a shutter closing time when the shutter moves from the passing position to the blocking position in the non-energized state of the electrical biasing means,
The laser processing apparatus according to claim 1, wherein the shutter abnormality detection unit determines a drive abnormality of the mechanical biasing unit and notifies the shutter abnormality when the shutter closing time is larger than the reference time. In the laser processing apparatus according to any one of claims 1 to 5,
The transition time detecting means detects a shutter opening time when the shutter moves from the blocking position to the passing position as the transition time,
The shutter abnormality detection means determines an abnormality based on the shutter opening time and the reference time, and notifies the shutter abnormality,
and,
The transition time detecting means detects a shutter closing time when the shutter moves from the passing position to the blocking position as the transition time,
The shutter abnormality detection means determines an abnormality based on the shutter closing time and the reference time, and notifies the shutter abnormality,
The laser processing apparatus, wherein the reference time for abnormality determination based on the shutter opening time and the reference time for abnormality determination based on the shutter closing time are set to different times. In the laser processing apparatus according to any one of claims 1 to 6,
The laser processing apparatus, wherein the reference time is set to a unique value for each laser processing apparatus. In the laser processing apparatus according to any one of claims 1 to 7,
A laser processing apparatus for forcibly stopping the laser light source when an abnormality is determined by the shutter abnormality detecting means. In the laser processing apparatus according to any one of claims 1 to 8,
The laser processing apparatus according to claim 1, wherein a predetermined time is subtracted from a time corresponding to the shutter life or a predetermined time is set as the reference time for the reference time.

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