JP2011050992A - Laser beam machining apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser beam machining apparatus that performs machining while automatically recognizing machining regions corresponding to a workpiece. <P>SOLUTION: The laser beam machining apparatus includes: a machining means 2 that converges a laser beam L from a laser oscillating means 13 to emit the laser beam to the workpiece W of a metallic plate in which a projected frame Wf is provided on the periphery; a machining position moving means 12 that moves the machining position of the machining means 2 in the planar direction relative to the workpiece W; and a control means 11 that controls the laser oscillating means 13 and the machining position moving means 12. The apparatus is also equipped with a projected frame position detecting means 15 for detecting the position of the projected frame Wf of the workpiece W. The control means 11 determines, on the basis of the positional information from the projected frame position detecting means 15, a machining regions where the machining means 2 does not come into contact with the projected frame Wf of the workpiece W. The control means then drives and controls the machining position moving means 12 in a manner displacing the machining position of the machining means 2 within the machining region. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a laser processing apparatus that processes a workpiece such as a thin metal plate with laser light emitted from a processing head, and more particularly to a laser processing apparatus that shortens the processing time by safely moving the processing head at high speed.

  As shown in FIG. 5, the laser processing apparatus condenses the laser light L incident from the laser oscillator 101 via the reflection mirror 102 by the condenser lens 103 and passes through the nozzle 106 provided at the lower end of the processing head 105. The workpiece W is irradiated with the laser light L. A workpiece W, which is a thin metal plate, is mounted on a machining stage 110 that can move in the X and Y directions. The machining stage 110 moves based on machining data preset by the controller 120, and works in conjunction with the laser oscillator 101. A plurality of drilling processes are performed.

  By the way, the workpiece W is installed on the processing stage 110 such that the peripheral portion thereof is sandwiched between the holders 111, and the holder 111 protrudes from the peripheral portion of the workpiece. In addition to these, there is also a work W itself having a convex frame at the peripheral edge. In such a case, it is necessary to prevent the machining head 105 that moves relative to the workpiece W from colliding with the holder 111 or the like during machining. Therefore, conventionally, a sensor is attached to the machining head 105 or the like, and the movement of the machining stage 110 is forcibly stopped by detecting the holder 111 or the like by the sensor, thereby preventing damage due to collision with the machining head 105.

JP 2004-174519 A Japanese Patent Laid-Open No. 06-007975 JP 2000-284819 A

  However, if the sensor detects the holder 111 or the like while the machining program is being executed by the controller 120, the machining is forcibly stopped, the machining program is abnormally interrupted, and subsequent machining of the workpiece W cannot be performed. Waste material. Further, it is necessary to secure a certain moving distance (idle running distance) from when the sensor detects the holder 111 to when the machining head 105 stops completely. Therefore, the conventional laser processing apparatus provided with the sensor has a problem that the processing area of the workpiece W becomes narrow. That is, since the machining is performed at the center of the machining head 105, the area considering the free running distance for stopping in addition to the distance at which the machining head 105 contacts the holder 111 or the like becomes a non-machining area, and the material is wasted. Will increase. This means that if the relative movement speed of the machining head 105 is increased in order to shorten the machining time, the idle running distance becomes longer and a large non-machining area is required.

  On the other hand, in a processing operation by a laser processing apparatus, an operator attaches a workpiece to the processing stage 110, but a workpiece of a different size may be erroneously attached. In that case, since the size of the workpiece corresponding to the set machining data and the actual workpiece are different, if the actual workpiece size is large, the set machining area will be small, and the unmachined part will increase, resulting in wasted material. If the actual work size is small, the machining head 105 collides with the holder 111 or the like and is damaged due to the large machining area.

  Accordingly, an object of the present invention is to provide a laser processing apparatus that performs processing by automatically recognizing a processing region corresponding to a workpiece in order to solve such a problem.

  A laser processing apparatus according to the present invention includes a processing means for condensing and irradiating a laser beam from a laser oscillating means onto a metal plate work having a convex frame at a peripheral edge thereof, and a planar direction for the work. Convex frame position for detecting a position of the convex frame of the workpiece, comprising: a processing position moving unit that moves a processing position of the processing unit; and a control unit that controls the laser oscillation unit and the processing position moving unit. Detecting means, and the control means calculates a machining area where the machining means does not hit the convex frame of the workpiece based on position information from the convex frame position detection means, and the machining means within the machining area The machining position moving means is driven and controlled so as to displace the machining position.

In the laser processing apparatus according to the present invention, it is preferable that the control unit is configured to collate with a preset work size based on position information from the convex frame position detection unit. .
Further, in the laser processing apparatus according to the present invention, the control unit performs the operation on the workpiece from the stop command to the processing position moving unit to the actual stop based on the position information from the convex frame position detection unit. It is preferable that the stop start position is calculated in consideration of the movement distance of the processing means and the stop control is performed.
In the laser processing apparatus according to the present invention, after the control unit calculates a processing region for the convex frame of the workpiece, the control unit performs invalidation that does not react to detection of the convex frame by the convex frame position detection unit. It is preferable.
In the laser processing apparatus according to the present invention, the processing position moving unit is preferably an XY table that holds the work and moves the work in a planar direction.

  According to the present invention, the machining means calculates the area where the workpiece does not hit the convex frame of the workpiece, and the machining position moving means is driven so as to move the machining position of the machining means within the area. Can be processed to the maximum, and the waste of material can be eliminated, and since the processing means does not move to the area where the processing means collides with the convex frame of the workpiece, the moving speed due to idle movement is maximized As a result, the processing time can be further shortened.

It is the figure which showed the process part of the laser processing apparatus. It is the figure which showed notionally the main structures of the laser processing apparatus. It is the top view which simplified and showed the relationship between a process stand and a workpiece | work. It is the figure which showed the flowchart of the process preparation process which a controller performs in starting a process. It is the figure which showed the laser processing apparatus notionally.

Next, an embodiment of a laser processing apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a processing portion of a laser processing apparatus.
The laser processing apparatus 1 is configured such that a thin metal plate workpiece W is sandwiched between a processing head 2 and a processing table 4 which are processing means, and processing can be performed by a laser beam L irradiated from the processing head 2 side. is there.

  The machining head 2 is fixed to the mounting base 3, and a machining stage (not shown) as position driving means is provided below the machining head 2. This processing stage is an XY table. The workpiece W which is a target in the present embodiment is a metal plate having a convex frame Wf formed on the peripheral edge thereof, and the convex frame Wf is held by a mounting portion of the processing stage and is set in a processable state. A laser beam L is sent from an unillustrated laser oscillator through an optical fiber 5 to the machining head 2 that performs drilling on the workpiece W. The processing head 2 is formed in a cylindrical shape, and the laser light L sent through the optical fiber 5 becomes parallel light through a collimator lens (not shown), and further passes through the condenser lens to the processing position of the workpiece W. Condensed.

  The processing table 4 disposed below the workpiece W so as to face the processing head 2 is configured in a hollow cylindrical shape so that the assist gas can be sucked under the workpiece W. The assist gas flows into the processing table 4 through the cutting portion of the workpiece W and is drawn in by vacuuming. Accordingly, dross, spatter, and the like that are generated as the workpiece W is processed are sent and discharged according to the flow of the assist gas.

  In the laser processing apparatus 1, a workpiece W fixed to a processing stage is sandwiched between a processing head 2 and a processing table 4 as shown in the figure. Then, the workpiece W itself is moved by the operation of the machining stage based on preset machining data, and predetermined drilling is performed by the laser light L emitted from the machining head 2. In the laser processing apparatus 1 according to the present embodiment, the fixed processing head 2 and the processing table 4 are moved relative to the workpiece W by driving the processing stage. Such movement will be described simply as movement of the machining head 2 and the machining table 4.

  Next, FIG. 2 is a diagram conceptually showing main components of the laser processing apparatus 1 for performing laser processing, and particularly shows a laser oscillator, a processing stage, and a controller for driving them. The controller 11 stores processing data for performing predetermined drilling processing on the workpiece W, and processing for controlling the drive unit 12a of the processing stage 12 and the laser oscillator 13 to perform processing according to the processing data. I have a program.

  In the laser processing apparatus 1, the workpiece W is moved by driving the processing stage 12, and the processing head 2 and the processing table 4 are moved with respect to the workpiece W. The machining program has a configuration for checking in advance the movable area of the machining head 2 and the machining table 4 and setting the movable area based on the confirmed area. In particular, in the present embodiment, a movable region of the processing table 4 is set, and FIG. 3 is a plan view showing the relationship between the processing table 4 and the workpiece W in a simplified manner.

  The workpiece W is a rectangular thin metal plate, and a convex frame Wf having a predetermined height is provided at the peripheral edge portions of the four sides as shown in FIG. The processing table 4 is provided with a sensor 15 which is a convex frame position detecting means for detecting the convex frame Wf of the workpiece W. In this embodiment, as shown in FIGS. 1 and 2, when the workpiece W is attached to the processing stage 12, the convex frame Wf faces downward, and therefore it is necessary to consider the collision of the processing table 4 with the convex frame Wf. It is.

  The sensor 15 is originally provided to detect a position before the processing head 2 or the processing table 4 that is a processing means collides with the convex frame Wf. In the present embodiment, the sensor 15 corresponds to the convex frame Wf. Thus, it is used for confirming the position where the processing means can move. The sensor 15 has four sensor arms 21 protruding from the processing table 4 in the XY directions of the processing stage 12 by the bias of the spring, and when the sensor 15 collides with the convex frame Wf and is pushed inward, the inside of the processing table 4 Thus, detection is performed by blocking the sensor light.

  In the laser processing apparatus 1, a detection signal is transmitted from the sensor 15 to the controller 11 by the contraction operation of the sensor arm 21, and the controller 11 determines the movement limit of the processing table 4. The sensor 15 may be provided on the processing head 2 side. However, since the structure is complicated, in the present embodiment, the sensor 15 is provided on the processing table 4 side. Is attached.

  Next, FIG. 4 is a diagram showing a flowchart of a processing preparation process performed by the controller 11 when starting processing. This machining preparation process is incorporated as a sub-flow in the main flow for executing the machining program. When the operator sets the workpiece W on the processing stage 12 and presses the processing switch, processing of the laser processing apparatus 1 is started. Immediately after the processing starts, the sub-flow processing preparation process shown in FIG. 4 is executed. The

In the processing preparation step, first, the processing stage 12 is driven, and the processing table 4 moves in one reciprocal direction in the XY directions. The movement is up to a position where the four sensor arms 21 projecting from the processing table 4 are abutted against the convex frame Wf in the movement direction, and the position of the convex frame Wf is detected by the controller 11 receiving the detection signal from the sensor 15. It is detected (S101). The controller 11 calculates the size of the workpiece W, that is, the workpiece end coordinate that is the inner position of the convex frame Wf based on the information from the sensor 15 (S102).
The center coordinates of the machining area of the workpiece W are also obtained from the workpiece coordinates calculated at this time. By using this center coordinate as a reference point (center point) of processing data when processing, it becomes possible to mount the workpiece W without worrying about the installation position.

Since workpieces W having different sizes may be used as workpieces to be machined, the size of the workpiece W previously set on the machining stage 12 is inputted by the worker before machining. Therefore, when the size of the workpiece W actually set on the machining stage 12 is obtained by calculating the workpiece end coordinates in S102, the workpiece size is then compared with the workpiece size input in advance. (S103).
If the calculated size of the workpiece W is different from the input value (S103: NO), an alarm is given to notify that the workpiece W of a different size is attached by mistake, and the machining is prohibited. (S104). In this case, after the wrong workpiece W is removed and the correct size workpiece W is set, the machining switch is pressed again to check the workpiece W (S101 to S103).

  On the other hand, when the calculated size of the workpiece W matches the input workpiece size (S103: YES), a stroke limit indicating a machining area in which the machining table 4 is movable is calculated (S105). . The processing table 4 has a nozzle tip of the processing head 2 at the center position O, and laser light L is output from the nozzle tip, and drilling is performed. Therefore, the machining position where the machining table 4 is prevented from coming into contact with the convex frame Wf is a position further inside from the convex frame Wf, and the work W has a non-machining region 50 shown in FIG. By calculating the stroke limit, a machining limit line 51 indicated by a one-dot chain line inside the non-machining region 50 is obtained. That is, the stroke limit indicates the position where the processing table 4 hits the convex frame Wf with reference to the center coordinates of the workpiece W obtained in step S102.

  Positioning of the processing table 4 with respect to the workpiece W by the controller 11 is performed with reference to the center position O which is the irradiation position of the laser light L. Therefore, when the machining program is executed by the controller 11, position control is performed so that the center position O of the machining table 4 does not exceed the stroke limit. That is, in the present embodiment, positioning in the non-processable region 50 that exceeds the processing limit line 51 is prohibited in advance, and the processing table 4 is prevented from colliding with the convex frame Wf.

  Next, when the movement of the processing table 4 with respect to the workpiece W is stopped, it is necessary to consider the idle running distance from when the controller 11 issues a stop command until it actually stops. This is because, when the processing table 4 is moved at a high speed, the free running distance becomes long, and at that time, the processing table 4 may collide. In the machining program, a plurality of machining locations are set for one workpiece W attached to the machining stage 12, and the machining table 4 moves between the machining locations, and is an empty space that does not perform machining. Faster when moving. Therefore, in order to prevent the center position O of the processing table 4 from entering the non-processable region 50, it is necessary to perform control in consideration of the free running distance until the stop at the time of high speed movement.

  Therefore, in this embodiment, after the stroke limit is calculated in S105, the stop start position obtained by adding the idle travel distance is calculated (S106). For example, when the moving speed of the processing table 4 by driving the processing stage 12 is 20 m / min, a free running distance of 5 to 10 mm is required. In S106, the stop start position 52 is obtained from the free running distance corresponding to the speed during high-speed movement. Therefore, during the execution of the machining program, when the center position O of the machining table 4 reaches the stop start position 52 shown in FIG. Stop control is performed so as to stop completely. Note that the distance from the stop start position 52 to the machining limit line 51 is a stop distance during idle movement (high speed movement) where machining is not performed, and at a moving speed during machining execution that is slower than that, the distance until the stop is reached. Since the distance is shortened, a stop start position (not shown) that does not decelerate even when the stop start position 52 is exceeded and starts to decelerate further is set. That is, the stop start position corresponding to the moving speed of the processing table 4 is determined with the maximum distance from the stop start position 52 to the processing limit line 51.

  Thus, in this embodiment, the movement of the machining head 2 and the machining table 4 is controlled according to the position coordinates of the machining limit line 51 and the stop start position 52. Therefore, the controller 11 is invalidated so as not to react to the detection of the sensor 15 so as not to react even if a detection signal from the sensor 15 is received so that the machining is not interrupted by the detection of the sensor 15 at the time of machining. S107). This is because the sensor 15 uses the configuration of the conventional laser processing apparatus as described above, and is originally provided for the processing table 4 to detect a collision with the convex frame Wf. This eliminates the need to provide a new sensor and eliminates the need for significant changes in the machining program, thereby reducing costs.

  Then, the preparation for machining is completed by executing S107, and thereafter, the process returns to the main flow to perform drilling of the workpiece. That is, the processing stage 12 moves to the workpiece W sandwiched between the processing head 2 and the processing table 4 based on preset processing data, and the laser beam irradiated from the processing head 2 to a predetermined position of the workpiece W. With L, a plurality of holes are drilled in a predetermined pattern. Since a plurality of the machining operations are performed on one workpiece W, after the drilling process of a predetermined pattern is performed at one place, the machining head 2 and the machining table 4 are greatly moved to other places, Again, a predetermined pattern of drilling is performed.

  The movement of the machining head 2 and the machining table 4 with respect to the workpiece W is controlled within the machining area excluding the non-machining area 50. Therefore, in the laser processing apparatus 1 of the present embodiment, the sensor 15 is invalidated, and even if the sensor arm 21 of the processing table 4 hits the convex frame Wf, the processing can be performed up to the processing limit region without being wasted. It becomes possible. Further, since the machining head 2 and the machining table 4 are moved only within the machining area excluding the non-machining area 50, the moving speed due to idle movement can be maximized, and the machining time can be further shortened. Further, the invalidation of the sensor 15 can avoid an abnormal interruption of the machining program, thereby eliminating the waste of material due to the interruption of the machining and shortening the machining time.

  Furthermore, in the laser processing apparatus 1 of the present embodiment, the workpiece size is collated by calculating the workpiece end coordinates, and if a workpiece W of a different size is erroneously attached, an alarm or the like is issued. For this reason, when the size of the workpiece W is large with respect to the processing region, the unprocessed portion is increased and the material is wasted. However, such waste or the like is eliminated. Further, the maximum machining area to be machined based on the machining data is compared with the machining limit area obtained in step S105. When the size of the workpiece W is small with respect to the machining area, the maximum machining area exceeds the machining limit area. Therefore, the start of processing is prohibited. Thereby, it is possible to prevent the machining program from being interrupted abnormally or machining a workpiece having an incorrect dimension.

As mentioned above, although embodiment of the laser processing apparatus concerning this invention was described, this invention is not limited to this, A various change is possible in the range which does not deviate from the meaning.
In the above embodiment, the laser processing apparatus 1 in which the processing stage side that holds the workpiece W is driven and the fixed processing head 2 and the processing table 4 move relative to the workpiece W is shown. The processing head 2 and the processing table 4 may be moved with respect to W.
In the above embodiment, the optical sensor that reacts with the sensor arm 21 is used as the sensor 15 for confirming the position. However, if the work end coordinates of the work W can be confirmed, it is obtained from an image, for example. May be.

1 Laser processing device 2 Processing head 2
4 Processing Table 5 Optical Fiber 11 Controller 12 Processing Stage 13 Laser Oscillator 15 Sensor L Laser Light W Work Wf Convex Frame

Claims (5)

Processing means for condensing and irradiating laser light from a laser oscillation means to a metal plate workpiece having a convex frame at the peripheral edge, and moving the processing position of the processing means in the plane direction with respect to the work In a laser processing apparatus having a processing position moving means and a control means for controlling the laser oscillation means and the processing position moving means,
A convex frame position detecting unit that detects a position of the convex frame of the workpiece is provided, and the control unit performs processing in which the processing unit does not hit the convex frame of the workpiece based on position information from the convex frame position detecting unit. A laser processing apparatus characterized by calculating an area and drivingly controlling the processing position moving means so as to displace the processing position of the processing means within the processing area. In the laser processing apparatus according to claim 1,
The laser processing apparatus according to claim 1, wherein the control means is configured to collate with a preset workpiece size based on position information from the convex frame position detection means. In the laser processing apparatus according to claim 1 or 2,
The control means is based on the position information from the convex frame position detection means, and is a stop start position in consideration of the movement distance of the machining means relative to the workpiece from the stop command to the machining position movement means until the actual stop. Is calculated, and stop control is performed. In the laser processing apparatus according to any one of claims 1 to 3,
The control unit is configured to perform invalidation that does not react to detection of a convex frame by the convex frame position detection unit after calculating a processing region for the convex frame of the workpiece. . In the laser processing apparatus according to any one of claims 1 to 4,
The laser processing apparatus, wherein the processing position moving means is an XY table that holds the work and moves the work in a planar direction.

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