JP2013166171A - Laser processing apparatus and origin correction method for laser processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow an origin position and a rotation center in the laser beam irradiation to match even if it is a laser processing apparatus of the structure in which laser beams cannot be moved to the origin position.SOLUTION: A circular processing mark is formed on a processing object OB by moving the irradiation position of laser beams by a distance X1 set from the origin position of the laser beam irradiation, by rotating the processing object OB set on a table 11 after the movement, and by irradiating with laser beams the processing object OB from a processing head 20. Next, a straight processing mark is formed on the processing object OB, by stopping the rotation of the processing object OB, by moving it in the radial direction, and by irradiating with laser beams the processing object OB from the processing head 20. The shift amount of the origin position to the rotation center is calculated by photographing the surface of the processing object OB with a camera 40, by measuring the radius R of the circular processing mark and the distance De between the center of the circular processing mark and the straight processing mark, and by using the measured radius R and the distance De.

Description

  The present invention rotates a processing object and irradiates a laser beam, and moves the irradiation position of the laser beam relative to the processing object, thereby causing pits, grooves or reaction traces (hereinafter collectively referred to as generic names) on the surface of the processing object. The present invention relates to a laser processing apparatus that forms a processing trace). The present invention also relates to a method for correcting the origin of a laser processing apparatus in which the origin position and the rotation center in laser beam irradiation in the laser processing apparatus are matched.

  Conventionally, the processing object is set on the surface of the processing object by rotating the processing object set on the table and irradiating laser light, and moving the irradiation position of the laser light in one direction relative to the processing object. A laser processing apparatus for forming is known. For example, in Patent Document 1 below, a glass substrate on which a photoresist layer is formed is set on a table, and the laser beam collected while rotating the table is moved in the radial direction to form a latent image on the photoresist layer. A laser processing apparatus is shown. By developing a glass substrate on which a latent image is formed on a photoresist layer with a developer, an optical disc master on which a concavo-convex pattern is formed can be created. In such a laser processing apparatus, in order to improve the processing accuracy by matching the set irradiation position of the laser beam and the actual irradiation position of the laser beam, the origin and rotation center of the irradiation position of the moving laser beam are Need to match.

  In the laser processing apparatus, as a method for matching the origin of the moving laser beam irradiation position with the rotation center, for example, there is a method disclosed in Patent Document 2 below. In this method, first, a laser beam is irradiated to the origin position, and the origin position is acquired by camera photography. Next, the table is rotated, the locus of laser light irradiation is acquired by camera photography, and the center of rotation is detected from this locus. A vector heading from the origin position in the camera coordinate system to the center of rotation is converted into a vector in the coordinate system for detecting the moving position of the laser beam, and the origin position of the laser beam is moved by this converted vector. In this case, the conversion coefficient regarding the conversion of the coordinate system is calculated by acquiring the position of the camera coordinate system and the position of the coordinate system for detecting the moving position of the laser light with respect to the two irradiation positions of the laser light. can do. According to this method, the origin of the irradiation position of the laser beam and the rotation center can be matched, and the processing accuracy can be improved.

  On the other hand, for example, as shown in Patent Document 3 below, laser processing is performed by setting a plurality of workpieces along a circumferential direction on a table and moving a laser beam irradiation position by a predetermined width in the radial direction. Devices that perform are also known.

Japanese Patent Laid-Open No. 11-203735 JP 2006-272355 A JP 2008-937723 A

  In the case of the apparatus shown in Patent Document 3, the laser beam irradiation position is often configured to be unable to move to the origin position (position near the rotation center pole), and in such a case, In the apparatus and method disclosed in Patent Document 2, the origin of the irradiation position of the laser beam and the rotation center cannot be matched. Even in the case where the laser processing apparatus sets and processes a single workpiece, in the case of the apparatus for creating an optical disc master described in Patent Document 1, the irradiation position of the laser beam is set to the origin position. In some cases, the apparatus and method disclosed in Patent Document 2 may be configured such that the origin of the irradiation position of the laser beam and the rotation center are not possible. Cannot be matched.

  The present invention has been made to address the above problems, and even in a laser processing apparatus having a structure in which the laser beam cannot be moved to the origin position, the origin of the laser beam irradiation position coincides with the rotation center. An object of the present invention is to provide a laser processing apparatus that can be used. In addition, in the description of each constituent element of the present invention below, in order to facilitate understanding of the present invention, reference numerals of corresponding portions of the embodiment are described in parentheses, but each constituent element of the present invention is The present invention should not be construed as being limited to the configurations of the corresponding portions indicated by the reference numerals of the embodiments.

In order to achieve the above object, the present invention is characterized in that a table (11) for setting a processing object, a rotating means (12) for rotating the table, and a processing object set on the table are irradiated with laser light. And a laser beam movement that moves the irradiation position of the laser beam irradiated by the processing head on a line that is in the vicinity of the rotation center of the table by the rotating means and includes the origin position in the laser beam irradiation. Means (13-15), laser light irradiation position adjusting means (34) for adjusting the irradiation position of the laser light in the direction perpendicular to the moving direction of the laser light by the laser light moving means, and moving from the origin position by the laser light moving means In a laser processing apparatus comprising distance detection means (63) for detecting a distance to a laser beam irradiation position on a line to be The laser beam moving means is controlled using the distance detected by the emitting means, and the laser light irradiation position is moved from the origin position to a position having a preset distance, and the laser light irradiation position is moved. The circular processing trace forming means for controlling the rotation means to rotate the processing target set on the table and irradiating the processing target with laser light from the processing head to form a circular processing trace on the processing target ( (S102 to S120) and while moving the laser beam irradiation position by the laser beam moving means, the processing object set on the table is irradiated with laser light from the processing head, and a linear processing mark is formed on the processing object. Straight machining trace forming means (S122 to S136) to be formed and machining diameter measuring means (40) for observing the surface of the workpiece set on the table and measuring the radius of the circular machining trace. 41, S138 to S162, S214 to S272, and S338 to S412), and the center for measuring the distance between the center of the circular processing trace and the linear processing trace by observing the surface of the workpiece set on the table. -Straight line distance measuring means (40, 41, S138 to S274, S338 to S416), the radius of the measured circular machining trace, and the distance between the center of the measured circular machining trace and the linear machining trace. And a preset distance, which is a distance from the origin position of the laser beam irradiation position when forming a circular processing mark, to calculate the deviation amount of the origin position from the actual rotation center by the rotating means A deviation amount calculation means (S276, S418) is provided.

  According to this, even in a laser processing apparatus having a structure in which the laser beam cannot be moved to the origin position, the relationship between the origin position and the rotation center in the laser beam irradiation can be obtained, and the laser is based on this relationship. If the origin position in the light irradiation is moved, the origin position in the laser light irradiation and the rotation center can be matched.

  Another feature of the present invention is that, in the above-described present invention, the circular processing mark forming means has two different positions which are a first distance and a second distance preset from the origin position of the laser beam irradiation position. The first circular machining trace and the second circular machining trace are formed on the workpiece at two different positions, respectively, and the machining diameter measuring means has the first circular machining trace and the second circular machining trace. The radius of the circular machining trace is measured, and the deviation amount calculating means calculates the radius of the measured first circular machining trace and the second circular machining trace, the center of the measured circular machining trace, and a straight line. Using the first distance and the second distance, which are distances from the origin position of the irradiation position of the laser beam when forming the first and second circular processing marks. Calculate the deviation of the origin position from the actual center of rotation by the rotating means. It lies in the fact.

  According to this, a plurality of relations between the origin position and the rotation center in laser light irradiation can be calculated, and if the average value or median value of those values is calculated, the origin position and rotation in laser light irradiation can be calculated more accurately. The relationship with the center can be obtained.

Another feature of the present invention is that the camera (40) for magnifying and photographing the workpiece set on the table, and the camera movement for moving the camera in the same direction as the laser beam movement direction by the laser beam irradiation position adjusting means. A rotation position control means (50, 61) for controlling the rotation position of the table by controlling the rotation start and stop of the rotation means, and the laser beam moving means (13-15), The processing head is fixed and the table and the rotating means are moved, and the processing diameter measuring means (40, 41, S138 to S162, S214 to S272) is used to determine the shooting position of the camera by the camera moving means and the laser beam moving means. Move and detect the shooting location where the distance between the processing marks of the circular processing marks is the maximum distance in the moving direction by the laser beam moving means from the image captured by the camera The radius of the circular machining trace is calculated from the distance between the machining traces of the circular machining trace at the photographing location, and the center-straight line distance measuring means (40, 41, S138 to S274) moves the camera by the camera moving means. The camera moving means in a state where the rotational position of the table is controlled by the rotational position control means so that the movement direction of the camera and the linear direction of the linear machining trace coincide with each other from the linear machining trace photographed by the camera. And the laser beam moving means to move the shooting position of the camera, and from the image shot by the camera, the shooting position where the distance between the linear processing mark and the circular processing mark is the maximum in the moving direction by the laser light moving means. The circular machining trace is detected from the distance between the linear machining trace and the circular machining trace at the photographing location and the radius of the circular machining trace calculated by the machining diameter measuring means. In calculating the distance between the center and the linear machining marks.

According to this, it is possible to calculate the relationship between the origin position and the rotation center in laser light irradiation only by providing the laser processing apparatus with a camera, a camera moving means, and a rotational position control means. Can be suppressed.

  Another feature of the present invention is that, instead of the above configuration, the camera (40) that magnifies and captures the workpiece set on the table, and the camera is the same as the laser beam moving direction by the laser beam irradiation position adjusting means. The camera moving means (41) for moving in the direction and the camera moving position detecting means (71, 50) for detecting the moving position of the camera by the camera moving means, and the laser beam moving means (13-15) are processed. The head and the rotating means are moved with the head fixed, and the processing diameter measuring means (40, 41, S338 to S412) moves the photographing position of the camera by the camera moving means and the laser beam moving means, The camera movement position detecting hand when at least three different portions of the circular processing trace are respectively photographed at predetermined positions of the image photographed by The coordinate value is calculated using the camera movement position detected by the camera and the distance detected by the distance detection means (63), and the radius of the circular machining trace is calculated from the calculated at least three coordinate values. The inter-distance measuring means (40, 41, S338 to S416) moves the photographing location of the camera by the camera moving means and the laser light moving means, and linear processing traces at predetermined positions of the image photographed by the camera. When at least two different points are photographed, a coordinate value is calculated using the camera movement position detected by the camera movement position detection means and the distance detected by the distance detection means, and at least two calculated values are calculated. Calculate the straight line formula of the linear machining trace from the coordinate value, and calculate the center coordinate of the circular machining trace from the three or more coordinate values calculated by the machining diameter measuring means. And, from the calculated linear equation and calculated circular machining marks the center coordinates to calculate the distance between the center and the linear machining traces of circular machining marks.

Even in this case, it is possible to calculate the relationship between the origin position and the rotation center in the laser light irradiation only by providing the laser processing apparatus with the camera, the camera moving means, and the camera moving position detecting means. Can be suppressed.

  Furthermore, in carrying out the present invention, the present invention is not limited to the invention of a laser processing apparatus, but may be applied to a laser processing apparatus as an origin correction method for a laser processing apparatus that corrects the origin position in laser light irradiation. It can be implemented. In this case, based on the deviation amount of the origin position from the actual rotation center by the calculated rotation means, the laser light irradiation position adjustment means is adjusted and the origin position on the line is corrected. It is good to do.

It is a whole block diagram of the laser processing apparatus of this invention. It is an enlarged view which expands and shows the processing head of FIG. It is a flowchart which shows the head part of the deviation | shift measurement program performed by the controller of FIG. 1 in 1st Embodiment. It is a flowchart which shows the 2nd part of the deviation | shift measurement program performed by the controller of FIG. 1 in 1st Embodiment. It is a flowchart which shows the 3rd part of the deviation | shift measurement program performed by the controller of FIG. 1 in 1st Embodiment. 6 is a flowchart showing a fourth (end) portion of the deviation measurement program executed by the controller of FIG. 1 in the first embodiment. It is explanatory drawing for demonstrating the moving direction of the processing target object with respect to the screen of a camera in 1st Embodiment. It is explanatory drawing for demonstrating the relationship between the origin position in the laser beam irradiation in 1st Embodiment, and the rotation center (center of a circular laser processing trace) of a table. (a)-(g) is explanatory drawing for demonstrating imaging | photography of the process trace by the camera in 1st Embodiment. It is a figure which shows the measurement point of the circular-shaped process trace formed in the process target object in 1st Embodiment, and a linear process trace. It is a flowchart which shows the head part of the deviation | shift measurement program performed by the controller of FIG. 1 in 2nd Embodiment. It is a flowchart which shows the 2nd part of the deviation | shift measurement program performed by the controller of FIG. 1 in 2nd Embodiment. It is a flowchart which shows the 3rd part of the deviation | shift measurement program performed by the controller of FIG. 1 in 2nd Embodiment. It is a flowchart which shows the 4th (end) part of the deviation | shift measurement program performed by the controller of FIG. 1 in 2nd Embodiment. It is a figure which shows the measurement point of the circular process trace formed in the process target object in 2nd Embodiment, and a linear process trace. It is explanatory drawing for demonstrating the relationship between the origin position in the laser beam irradiation in a modification, and the rotation center (center of a circular laser processing trace) of a table.

a. First Embodiment Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an overall configuration diagram of a laser processing apparatus according to the present invention. FIG. 1 is applicable not only to the first embodiment but also to a second embodiment described later. This laser processing apparatus includes a table 11 as a support member that sets and fixes and supports a processing object OB, and a processing head 20 that performs laser processing on the processing object OB by irradiating a laser beam toward the processing object OB. And a camera 40 for photographing the surface of the processing object OB.

  The table 11 is formed in a disk shape, and a workpiece OB is set on the upper surface of the table 11. In the present embodiment, the processing object OB is used to adjust the origin position of the laser beam irradiation by forming a circular processing mark, and thus has a single disk shape. However, as long as the adjustment of the origin position of the laser beam irradiation position is completed, any object can be applied as the object OB to be processed by the laser beam. For example, if a fixing jig capable of fixing various workpieces OB is installed on the upper surface of the table 11, a plurality of workpieces OB can be installed on the table 11. The table 11 is rotationally driven by a spindle motor 12.

  The spindle motor 12 rotates and drives the table 11 through the rotation shaft 12b. The spindle motor 12 incorporates an encoder 12a that detects the rotation of the motor 12, that is, the table 11, and outputs a rotation signal representing the rotation. This rotation signal is alternately switched between an index signal Index generated every time the rotation position of the table 11 comes to one reference rotation position and a high level and a low level each time the table 11 rotates by a predetermined minute angle. It consists of pulse train signals ΦA and ΦB. The index signal Index is used for detecting the reference rotation position of the table 11. The pulse train signals ΦA and ΦB are signals that are used to control the rotation speed of the table 11 and are out of phase with each other by π / 2 in order to identify the rotation direction.

  The index signal Index is supplied to the controller 50 and the rotation angle detection circuit 73, and the pulse train signals ΦA and ΦB are supplied to the spindle motor control circuit 61 and the rotation angle detection circuit 73. The spindle motor control circuit 61 starts rotation control in response to a rotation start instruction from the controller 50, calculates the rotation speed of the spindle motor 12 based on the number of pulses per unit time of the pulse train signals ΦA and ΦB output from the encoder 12a, The rotation of the spindle motor 12 is controlled so that the calculated rotation speed becomes equal to the rotation speed instructed by the controller 50. Further, when the rotation angle is input from the controller 50, the spindle motor control circuit 61 rotates the spindle motor 12 at a low speed until the rotation angle input from the rotation angle detection circuit 73 described later becomes equal to the rotation angle input from the controller 50. Let This low speed rotation is a rotation speed at which the rotation of the spindle motor 12 stops at the same time as the drive signal to the spindle motor 12 stops.

  The rotation angle detection circuit 73 counts the number of pulses of the pulse train signals ΦA and ΦB output from the encoder 12a, and calculates the rotation angle from the value obtained by dividing the count number by the number of counts in one rotation of the spindle motor 12. The rotation angle is output as digital data to the controller 50 and the spindle motor control circuit 61 at a set cycle. Further, when the index signal Index is input from the encoder 12a, the rotation angle detection circuit 73 resets the count number to 0 and counts the pulse number from 0. That is, the timing at which the index signal Index is input is the reference rotation position (position of the rotation angle 0).

  The table 11 is linearly driven in the left-right direction in the figure by a feed motor 13 together with the spindle motor 12. A nut 14 is fixed to the spindle motor 12, and a screw rod 15 that is driven to rotate around an axis by a feed motor 13 at one end is screwed to the nut 14. The other end of the screw rod 15 is rotatably supported by a support base 16, and the support base 16 fixedly supports the feed motor 13. In this case, the spindle motor 12 and the nut 14 are guided by a guide member (not shown) so as to be movable only in the axial direction of the screw rod 15, and the nut 14 and the screw rod 15 constitute a screw feed mechanism.

  Accordingly, the table 11 and the spindle motor 12 are moved in the left-right direction in the drawing by the rotation of the screw rod 15 around the axis by the feed motor 13. Regarding the movement of the table 11, the illustrated left end of the table 11 can be moved to the right from the camera 40 in order to make it easier to set the workpiece OB on the table 11. Further, regarding the movement of the table 11 in the left direction in the drawing, the irradiation position of the laser beam on the processing object OB by the processing head 20 is left at a predetermined distance from the center of the table 11. In other words, the irradiation position of the laser beam can be moved from a position at a predetermined distance from the center (rotation center) of the table 11 to the outer peripheral edge of the table 11, and the photographing position of the camera 40 is opposite to the outer peripheral edge of the table 11. It can move to the outer periphery. Note that a state where the irradiation position of the laser beam on the object OB is left by a predetermined distance from the center of the table 11 is an initial position of the table 11 described later, and the predetermined distance is an initial value of the radius. The center of the table 11 is the origin in laser light irradiation, and this origin should be the center of rotation of the table 11, but it is slightly deviated from the actual center of rotation of the table 11 due to a design error or the like. There is often.

  Also incorporated in the feed motor 13 is an encoder 13a that detects the rotation of the feed motor 13 and outputs the same pulse train signals ΦA and ΦB as the encoder 12a. The pulse train signals ΦA and ΦB output from the encoder 13 a are output to the feed motor control circuit 62 and the radius value detection circuit 63. The radius value detection circuit 63 counts up or counts down the number of pulses of the pulse train signals ΦA and ΦB from the encoder 13a according to the rotation direction of the feed motor 13, and the table 11 is irradiated with laser light from the count value. A radius value r representing the feed position (ie radius position) is detected, and a signal representing the radius value r is output to the controller 50. The initial setting of the count value in the radius value detection circuit 63 is performed by an instruction from the controller 50 when the power is turned on.

  That is, the controller 50 instructs the feed motor control circuit 62 to move the nut 14 (that is, the table 11 and the spindle motor 12) to the initial position and the radius value detection circuit 63 when the power is turned on. In response to this instruction, the feed motor control circuit 62 rotates the feed motor 13 and moves the table 11 (spindle motor 12 and nut 14) to the left side to move to the initial position. This initial position is a drive limit position of the table 11 driven by the feed motor 13, and this position is such that the irradiation position of the laser beam on the workpiece OB described above is left by a predetermined distance from the center of the table 11. Corresponds to the state. The radius value detection circuit 63 continues to input the pulse train signals ΦA and ΦB from the encoder 13a while the table 11 is moving leftward. When the table 11 reaches the drive limit position (that is, the initial position) and the rotation of the feed motor 13 stops, the radius value detection circuit 63 detects the stop of the input of the pulse train signals ΦA and ΦB from the encoder 13a, and the count value Is set to an initial value (that is, a count value corresponding to the predetermined distance from the center of the table 11). At this time, the radius value detection circuit 63 outputs a signal for stopping the output to the feed motor control circuit 62, whereby the feed motor control circuit 62 stops outputting the drive signal to the feed motor 13. Thereafter, when the feed motor 13 is driven, the radius value detection circuit 63 counts up or counts down the number of pulses of the pulse train signals ΦA and ΦB according to the rotation direction of the feed motor 13, and based on the count value. The radius value r representing the feed position in the radial direction of the table 11 (that is, the irradiation position of the laser beam on the workpiece OB) is calculated, and a signal representing the radius value r is output to the feed motor control circuit 62 and the controller 50. Keep doing. The radius value detection circuit 63 counts up the count value when the table 11 moves in the right direction, and counts down the count value when the table 11 moves in the left direction.

  The feed motor control circuit 62 drives and controls the feed motor 13 according to an instruction from the controller 50 to move the irradiation position of the laser beam to a designated radial position of the table 11 or move the table 11 in the radial direction at a designated speed. Or Specifically, the feed motor control circuit 62 uses the radius value r detected by the radius value detection circuit 63 when instructed to move the irradiation position of the laser beam to the radius position designated by the controller 50. The rotation of the feed motor 13 is controlled, and the feed motor 13 is rotated until the detected radius value r becomes equal to the value corresponding to the radius position designated by the controller 50.

  When the feed motor control circuit 62 is instructed to move the irradiation position of the laser beam in the radial direction of the table 11 at the moving speed designated by the controller 50, the feed motor control circuit 62 uses the pulse train signals ΦA and ΦB output from the encoder 13a. The movement speed in the radial direction of the table 11 is calculated, and the rotation of the feed motor 13 is controlled so that the calculated movement speed becomes equal to the movement speed designated by the controller 50.

  Next, the processing head 20 will be described. The processing head 20 is fixed to a head support portion 16a extending upward from the support base 16 so as to face the table 11 (processing object OB). As shown in an enlarged view in FIG. 2, the processing head 20 includes a laser light source 21, irradiates the laser light emitted from the laser light source 21 toward the processing object OB, and receives the reflected light. It has become. Laser light emitted from the laser light source 21 enters the mirror 23 through the collimator lens 22, is reflected by the mirror 23, and is processed by the object OB through the polarization beam splitter 24, the quarter wavelength plate 25 and the objective lens 26. Concentrate on the surface. Further, the laser beam condensed on the surface of the processing object OB is reflected on the surface of the processing object OB. The reflected light reflected from the surface of the workpiece OB enters the polarization beam splitter 24 through the objective lens 26 and the quarter wavelength plate 25, is reflected by the polarization beam splitter 24, and is collected by the condenser lens 27 and the cylindrical lens 28. Then, the light is condensed on the quadrant photodetector 29.

  The processing head 20 also includes a photodetector 32 that receives partially reflected light of the laser light from the laser light source 21 by the polarization beam splitter 24 via the condenser lens 31. The condensing lens 31 condenses the partially reflected light on the photodetector 32. The photodetector 32 detects the amount of received light of the partially reflected light and outputs an electric signal representing the amount of received light. The amount of light received and detected by the photodetector 32 corresponds to the intensity of the laser light emitted from the laser light source 21. Further, the machining head 20 further includes a focus actuator 33 that drives the objective lens 26 in the optical axis direction.

  The parts 21 to 29 and 31 to 33 of the machining head 20 are accommodated in a housing 20a, and the housing 20a is moved by a minute amount in the direction perpendicular to the paper surface by a manual micrometer 34. In FIG. 1, the housing 20 a is illustrated as being moved left and right, but in actuality, the housing 20 a is configured to move in the normal direction of the paper surface. That is, the opposite side surface of the micrometer 34 in the housing 20a is assembled to a vertical plate constituting a part of the head support portion 16a via a member 35 that can be deformed by a minute amount, and the micrometer 34 is manually rotated. As a result, the machining head 20 is displaced by a minute amount in the horizontal direction in the figure (actually the direction perpendicular to the paper surface). By the movement of the housing 20a in the direction perpendicular to the paper surface by the micrometer 34, the origin position (that is, the laser light irradiation position) in the laser light irradiation is perpendicular to the paper surface, that is, the feed motor 13, the nut 14 and the screw rod 15. The table 11 (laser beam irradiation position) is changed to a direction perpendicular to the moving direction. Further, any mechanism may be used in place of the micrometer 34 as long as the position of the machining head 20 can be changed in a minute amount, and the structure with a spacer having a known thickness and the amount of movement by rotation are known. The structure which tightens the screw which is attached may be sufficient.

  The laser light source 21 is driven by a laser drive circuit 64. The laser drive circuit 64 is controlled by the controller 50 and outputs a laser drive signal corresponding to the light emission signal from the light emission signal supply circuit 65 to the laser light source 21 to drive and control the laser light source 21. The laser drive circuit 64 is supplied with an electrical signal representing the amount of laser light received from the photodetector 32, that is, the intensity of the laser light emitted from the laser light source 21. The laser drive circuit 64 feedback-controls the intensity of the laser light emitted from the laser light source 21 using the electrical signal representing the intensity of the laser light. The light emission signal supply circuit 65 is also controlled by the controller 50 to output a light emission signal for causing the laser drive circuit 64 to emit the laser light source 21.

  Next, focus servo control of laser light will be described. The reflected light from the surface of the workpiece OB of the laser light is received by the four-divided photodetector 29. The four-divided photodetector 29 is constituted by a four-divided light receiving element composed of four light receiving elements having the same square shape divided by dividing lines. A detection signal having a magnitude proportional to the intensity is output as a light reception signal (a, b, c, d). The quadrant photodetector 29 is fixed so that the reflected light is collected at the center where the four light receiving elements are arranged.

  The light reception signals (a, b, c, d) output from the quadrant photodetector 29 are input to the HF signal amplifier circuit 66. The HF signal amplification circuit 66 amplifies the received light signals (a, b, c, d) and outputs them to the focus error signal generation circuit 67. The focus error signal generation circuit 67 generates a focus error signal by calculation using the amplified light reception signals (a ′, b ′, c ′, d ′). In this embodiment, since the focus servo control by the astigmatism method is used, the calculation of (a ′ + c ′) − (b ′ + d ′) is performed, and the calculation result is used as a focus error signal, and the focus servo circuit 68 is used. Output to. The focus error signal (a ′ + c ′) − (b ′ + d ′) represents the amount of deviation of the focal position of the laser beam from the surface of the workpiece OB.

  The focus servo circuit 68 is controlled by the controller 50, generates a focus servo signal based on the focus error signal, and outputs the focus servo signal to the drive circuit 69. The drive circuit 69 drives and controls the focus actuator 33 in accordance with the focus servo signal to displace the objective lens 26 in the optical axis direction of the laser light. In this case, by generating a focus servo signal so that the value of the focus error signal (a ′ + c ′) − (b ′ + d ′) is always a constant value (for example, zero), the surface of the object OB is processed. The laser beam can be continuously collected.

  The camera 40 is a digital camera that magnifies and captures the surface of the processing object OB set on the table 11, and image data of the camera 40 is transmitted to the controller 50. The controller 50 displays the captured image on the display device 52 by an instruction from the input device 51 or by executing a program described later. The camera 40 is moved in a direction perpendicular to the paper surface by a motor 41 fixed to a camera support portion 16 b extending upward from the support base 16. That is, the camera 40 is assembled to the rotating shaft of the motor 41 via a screw feed mechanism, and moves in the direction perpendicular to the paper surface (that is, the same direction as the moving direction of the laser light irradiation position by the micrometer 34) by the rotation of the motor 41. It has come to be. The movable range of the camera 40 is that the shooting position of the camera 40 in the direction perpendicular to the paper surface is an extension of the moving line on the table 11 by the feed motor 13, nut 14 and screw rod 15 of the laser light emitted from the processing head 20. The movable range is a small amount on the lower side in the vertical direction of the paper and about 1/4 of the radius of the table 11 on the upper side in the vertical direction of the paper.

  The direction of the camera 40 is such that when the table 11 is moved in the left-right direction by the feed motor 13, the nut 14, and the screw rod 15, one point of the image displayed on the display device 52 by the image data is on the horizontal axis of the screen. It has been adjusted to move in parallel. If the orientation of the camera 40 is not set as described above before the actual work described later, the following work is performed. First, as shown in FIG. 4, the operator forms a linear groove or reaction trace A (hereinafter referred to as a linear processing trace A) on the workpiece OB by irradiation with laser light from the processing head 20. Then, when the table 11 is moved by the feed motor 13, the nut 14, and the screw rod 15 while photographing the machining trace A with the camera 40, the linear machining trace A displayed on the display device 52 moves in the vertical direction. In other words, as shown in FIG. 4, the orientation of the camera 40 is adjusted so that the processing trace A moves parallel to the horizontal axis of the screen. Further, the orientation of the camera 40 remains the same, and the program for forming the screen data to be displayed on the display device 52 from the image data captured by the camera 40 in the controller 50 is changed so that the processing trace A is on the horizontal axis of the screen. The orientation of the screen may be changed so as to move in parallel.

  Also incorporated in the motor 41 is an encoder 41a that detects the rotation of the motor 41 and outputs the same pulse train signals ΦA and ΦB as the encoders 12a and 13a. The pulse train signals ΦA and ΦB output from the encoder 41 a are input to the movement position detection circuit 71. When the movement position of the camera 40 is instructed from the controller 50, the motor drive circuit 72 controls the rotation of the motor 41 using the movement position t detected by the movement position detection circuit 71 described later, and the detected movement position. The motor 41 is rotated until t becomes equal to the movement position instructed from the controller 50.

The moving position detection circuit 71 counts up or down the number of pulses of the pulse train signals ΦA and ΦB output from the encoder 41a according to the rotation direction of the motor 41, and determines the shooting position of the camera 40 in the direction perpendicular to the paper surface from the count value. The movement position t to be represented is detected, and a signal representing the movement position t is output to the controller 50 and the motor drive circuit 72 at a set cycle. The initial setting of the count value in the movement position detection circuit 71 is performed according to an instruction from the controller 50 when the power is turned on.

  That is, the controller 50 instructs the motor drive circuit 72 to move the camera 40 to the initial position and the moving position detection circuit 71 to perform initial setting when the power is turned on. In response to this instruction, the motor drive circuit 72 rotates the motor 41 to move the camera 40 to the initial position by moving the camera 40 in the direction perpendicular to the paper surface. This initial position is a drive limit position of the camera 40 driven by the motor 41. The movement position detection circuit 71 continues to input the pulse train signals ΦA and ΦB from the encoder 41a while the camera 40 is moving in the direction perpendicular to the paper surface. When the camera 40 reaches the drive limit position (that is, the initial position) and the rotation of the motor 41 stops, the movement position detection circuit 71 detects the stop of the input of the pulse train signals ΦA and ΦB from the encoder 41a, and calculates the count value. Set to 0 which is the initial value. At this time, the movement position detection circuit 71 outputs a signal for stopping the output to the motor drive circuit 72, whereby the motor drive circuit 72 stops outputting the drive signal to the motor 41. After that, when the motor 41 is driven, the moving position detection circuit 71 counts up or down the number of pulses of the pulse train signals ΦA and ΦB according to the rotation direction of the motor 41, and the camera is based on the count value. The movement position t representing the photographing position in the direction perpendicular to the paper surface is calculated, and a signal representing the movement position t is continuously output to the motor drive circuit 72 and the controller 50 at a set cycle. The movement position detection circuit 71 counts up the count value when the camera 40 moves down in the vertical direction of the paper, and counts down the count value when the camera 40 moves up in the vertical direction of the paper.

  The controller 50 is an electronic control device including a microcomputer including a CPU, ROM, RAM, and the like, a storage device such as a hard disk and a nonvolatile memory, an input / output interface, and the like. The storage device stores various programs including a deviation measurement program shown in FIGS. Connected to the controller 50 are an input device 51 for an operator to instruct various parameters, processing, and the like, and a display device 52 for visually informing the operator of inspection results, operating conditions, and the like. .

  In the laser processing apparatus configured as described above, before describing the actual operation of matching the origin position in laser light irradiation with the rotation center of the processing object OB, the origin position in laser light irradiation and the processing object OB The principle for matching the rotation center will be described. As shown in FIG. 5, the origin position in the laser beam irradiation (the laser beam irradiation position when the radius value detected by the radius value detection circuit 63 when the laser beam irradiation position is moved by the feed motor 13 is “0”) And the actual rotation center of the table 11 (work object OB) by the spindle motor 12 is “O2”. Then, the feed motor 13 is rotated to move the laser beam irradiation position of the machining head 20 to the radial position X1 with respect to the origin position O1, and the spindle motor 12 is rotated to form a circular groove or reaction trace on the workpiece OB. (Hereinafter referred to as a circular processing mark). The processing object OB may be the same as the object to be laser processed by the laser processing apparatus, or may be another object as long as a circular processing mark can be formed. In this case, since the irradiation position of the laser light actually rotates relative to the processing object OB around the rotation center O2, a circular processing mark as indicated by a broken line around the rotation center O2 is processed. Formed on the object OB. Next, without rotating the spindle motor 12, the feed motor 13 is rotated to move the irradiation position of the laser beam of the processing head 20, and a linear groove or reaction trace (hereinafter referred to as linear processing) is formed on the processing object OB. Form a trace). In this case, since the irradiation position of the laser beam moves on a line passing through the origin position O1, a linear processing mark as shown by a broken line is formed on the processing object OB. Then, the radius value R of the formed circular machining trace and the distance De from the linear machining trace to the center of the circular machining trace are measured. The measurement of the radius value R and the distance De will be described later in detail.

そして、前記数１及び数２に基づいて、回転中心Ｏ２の座標値ｘを計算すると、座標値ｘは下記数３で表される。

なお、本実施形態においては、半径値検出回路６３は、図１において、レーザ光の照射位置がテーブル１１に対して左方向に移動する場合を正（すなわちテーブル１１が右方向に移動する方向を正）として半径値ｒを検出しているので、その方向を合わせるために、図５の座標においてはＸ軸の左方向を正として扱っている。 Now, the coordinate value of the origin O1 is (0, 0), the moving direction of the laser light irradiation position (processing head 20, table 11) by the feed motor 13 is the X direction, and the X direction vertical direction parallel to the table 11 ( When the direction of movement of the processing head 20 by the micrometer 34 and the direction of movement of the camera 40 by the motor 41 are Y directions and the coordinate value of the rotation center O2 is (x, y), the following equations 1 and 2 are established.

Then, when the coordinate value x of the rotation center O2 is calculated based on the equations 1 and 2, the coordinate value x is expressed by the following equation 3.

In the present embodiment, the radius value detection circuit 63 is positive in FIG. 1 when the irradiation position of the laser beam moves to the left with respect to the table 11 (that is, the direction in which the table 11 moves to the right). Since the radius value r is detected as positive), the left direction of the X axis is treated as positive in the coordinates of FIG. 5 in order to match the direction.

  Then, by using the calculated coordinate values x and y, the origin position O1 in the laser light irradiation is moved to the actual rotation center O2 of the laser light, so that the origin position in the laser light irradiation and the rotation center of the workpiece OB are obtained. Can be matched. In this coincidence, the initial value of the radius value r detected by the radius value detection circuit 63 is corrected, and the machining head 20 may be moved by adjusting the micrometer 34.

  Next, in the laser processing apparatus configured as described above, an actual operation for matching the origin position in the laser light irradiation and the rotation center of the workpiece OB will be described. The operator turns on the power (not shown) and operates the input device 51 to move the table 11 to the right drive limit position where the left end of the table 11 is on the right side of the camera 40 in FIG. When the power is turned on, the table 11 is moved to the drive limit position in the left direction in FIG. 1, and the radius value detection circuit 63 cooperates with the feed motor control circuit 62 as described above. Is set to the initial value. After the table 11 has moved to the right drive limit position, the operator sets the workpiece OB on the table 11 and operates the input device 51 to operate the origin position in laser light irradiation and the rotation center of the workpiece OB. The controller 50 is caused to execute a deviation measurement program for obtaining a deviation from the above.

  The execution of the deviation measurement program is started in step S100 in FIG. 3A. The processing from step S102 to step S136 is processing for forming a circular processing trace and a linear processing trace on the processing object OB. First, in step S102, the controller 50 instructs the spindle motor control circuit 61 to start rotating the table 11. In response to this instruction, the spindle motor control circuit 61 starts rotating the spindle motor 12 at a predetermined rotational speed and starts rotating the table 11 at a predetermined rotational speed. Next, in step S104, the feed motor control circuit 62 is instructed to move the laser beam irradiation position by the machining head 20 to a preset radial position X1 (see FIG. 5). The feed motor control circuit 62 rotates the feed motor 13 while inputting the radius value r from the radius value detection circuit 63 until the input radius value r becomes equal to the value representing the radius position X1, and the laser beam is irradiated. In this case, the irradiation position is set to the radial position X1.

  The controller 50 continues to determine “No” until the radius value r input from the radius value detection circuit 63 becomes equal to the value representing the radius position X1 in step S106, thereby irradiating position when the laser beam is irradiated. Wait until it reaches the radial position X1. When the radius value r input from the radius value detection circuit 63 reaches the radius position X1, it is determined as “Yes”, and in step S108, the emission signal supply circuit 65 is instructed to generate a continuous emission signal with non-processing intensity. At the same time, the laser drive circuit 64 is operated. In response to this instruction, the light emission signal supply circuit 65 supplies a continuous light emission signal having a non-process intensity to the laser drive circuit 64, and the laser drive circuit 64 has a signal intensity corresponding to the received light intensity of the laser light from the photodetector 32. Is fed back to cause the laser light source 21 to emit laser light having non-processing intensity. The laser beam having the non-processing intensity is condensed by the objective lens 26, and the processing target object OB on the table 11 is irradiated with the laser beam whose focal position is the radial position X1. Note that the workpiece OB is not processed with laser light with non-processing intensity, but laser light with non-processing intensity has sufficient intensity for focus servo control in the same manner as laser light with processing intensity.

  After the processing in step S108, the controller 50 instructs the focus servo circuit 68 to start focus servo control in step S110. The focus servo circuit 68 generates a focus servo signal based on the focus error signal supplied from the focus error signal generation circuit 67 in accordance with an instruction from the controller 50, and drives and controls the focus actuator 33 via the drive circuit 69. . As a result, focus servo control starts. Next, in step S112, the CPU 11 waits for the table 11 to reach the reference rotation position by continuing to determine “No” until the index signal Index is input from the encoder 12a of the spindle motor 12, and the index signal Index is input. And “Yes”, the process proceeds to step S114.

  In step S114, the controller 50 instructs the light emission signal supply circuit 65 to change the intensity of the laser light to the processing intensity. In response to this instruction, the light emission signal supply circuit 65 starts to supply a light emission signal having a continuous processing intensity to the laser drive circuit 64, and the laser drive circuit 64 feeds back a signal having an intensity corresponding to the received light intensity of the laser light from the photodetector 32. Then, the laser light source 21 is caused to emit laser light having a processing intensity. Thereby, the laser beam condensed and irradiated on the processing object OB has a processing intensity, and a circular processing mark starts to be formed on the object OB. Then, in step S116, it is determined that the table 11 reaches the reference rotation position by continuing to determine “No” until the index signal Index is input from the encoder 12a of the spindle motor 12, and when the index signal Index is input. In step S118, the light emission signal supply circuit 65 is instructed to return the light emission intensity of the laser light to the non-processing intensity. In response to this instruction, the light emission signal supply circuit 65 supplies a continuous light emission signal of non-processing intensity to the laser drive circuit 64, and the laser beam condensed and irradiated on the processing object OB has non-processing intensity. Return. By the processing so far, a circular processing mark is formed on the processing object OB at the radial position X1.

  After the process of step S118, the controller 50 instructs the spindle motor control circuit 61 to stop the rotation in step S120. In response to this instruction, the spindle motor control circuit 61 stops supplying the drive signal to the spindle motor 12. The controller 50 waits until the rotation angle input from the rotation angle detection circuit 73 does not change, and controls the feed motor so that the irradiation position of the laser beam becomes the minimum radial position (radial position at the drive limit position) in S122. The circuit 62 is instructed to move to the drive limit position. In response to this instruction, the feed motor control circuit 62 inputs the radius value r from the radius value detection circuit 63 and feeds the feed motor until the input radius value r becomes equal to the minimum radius value (radius value at the drive limit position). 13 is rotated so that the irradiation position of the laser beam becomes the minimum radius position. The controller 50 continues to determine “No” until the radius value r input from the radius value detection circuit 63 reaches the minimum radius value in step S124, thereby waiting for the laser beam irradiation position to become the minimum radius position. When the minimum radius value is input, “Yes” is determined, and the process proceeds to step S126. In step S126, the controller 50 instructs the feed motor control circuit 62 to move at a preset high speed in the direction in which the radius value increases, and in step S128, the light emission signal supply circuit 65 transmits the laser beam. Instructs the emission intensity to be the processing intensity. In response to this instruction, the feed motor control circuit 62 has the moving speed calculated from the number of pulses of the pulse signal input per unit time from the encoder 13a in the feed motor 13 as the speed indicated by the controller 50. The feed motor 13 is driven. The light emission signal supply circuit 65 supplies a light emission signal having a continuous processing intensity to the laser drive circuit 64. As a result, the table 11 and the processing object OB move in the radial direction, and the processing object OB is irradiated with laser light having a processing intensity.

  After the process of step S128, the controller 50 continues to determine “No” until the radius value r input from the radius value detection circuit 63 becomes equal to the radius value X1 in step S130. If it becomes equal to the value X1, “Yes” is determined and the process proceeds to step S132. In step S132, the controller 50 instructs the focus servo circuit 68 to stop the focus servo. In step S134, the controller 50 instructs the laser drive circuit 64 and the light emission signal supply circuit 65 to stop laser light irradiation. To instruct the feed motor control circuit 62 to stop moving. In response to this instruction, the focus servo circuit 68 stops the supply of the focus servo signal, the focus servo stops, the laser drive circuit 64 and the light emission signal supply circuit 65 stop outputting the signal, and the laser beam Irradiation stops, the feed motor control circuit 62 stops supplying the drive signal to the feed motor 13, and the movement of the table 11 stops. By the processing so far, in addition to the circular processing trace, a linear processing trace is formed from the minimum radius position (radial position at the drive limit position) to the radial position X1 on the processing object OB.

  The processing from step S138 to step S268 is performed while moving the table 11 (moving in the X direction) and moving the camera 40 (moving in the Y direction) with the linear direction of the linear machining trace being the Y direction. By taking the position data and image data of the circular machining trace and the linear machining trace formed on the workpiece OB by the camera 40, the radius R of the circular machining trace and the center O2 of the circular machining trace are obtained. This is a process of acquiring data for calculating the distance De to the straight machining trace. Specifically, in the circular processing trace, data of the X direction position (position in the moving direction of the table 11) at the points P and T2 in FIG. 7 is acquired, and in the linear processing trace, the data in FIG. Data on the position in the X direction at point T1 is acquired. The points P and T2 are points where the line perpendicular to the linear processing trace passes through the center of the circular processing trace and crosses the boundary line between the circular processing trace and the non-processing trace, and the T1 point is a straight line. It is a point on the boundary line between the processed mark and the non-processed mark. Since the processing trace has a width, there are two boundary lines between the processing trace and the non-processing trace on the right side and the left side as shown in FIG. 7, and necessary data can be acquired by using either boundary line. In this embodiment, the right boundary line is used. If these data are obtained, the radius R of the circular machining trace is a value obtained by halving the difference in the X-direction position between the point P and the point T2, and is linear from the center O2 of the circular machining trace. The distance De to the processing trace can be calculated as a value obtained by subtracting the difference in the X direction position between the point P and the point T1 from the radius R of the circular processing trace. Of the processes from step S138 to step S268, the processes from step S138 to step S212 are performed by setting the straight machining trace parallel to the Y direction (the movement direction of the camera 40) and the X at the point T1 in FIG. The process from step S214 to step S268 is a process for acquiring the data in the X direction at points P and T2 in FIG.

  After the process of step S136, the controller 50 takes in the rotation angle data Θ input from the rotation angle detection circuit 73 in step S138, and adds the rotation angle data obtained by adding 90 ° to the rotation angle acquired in step S140. Output to the spindle motor control circuit 61. In response to the input of the rotation angle data, the spindle motor control circuit 61 rotates the spindle motor 12 at a low speed until the rotation angle data Θ input from the rotation angle detection circuit 73 becomes equal to the rotation angle input by the controller 50. Thereby, the linear processing trace is almost parallel to the Y direction (the moving direction of the camera 40). In this embodiment, it is assumed that the spindle motor 12 (table 11) rotates counterclockwise (the laser beam irradiation position rotates clockwise), but 90 ° is added to the acquired rotation angle. When rotating in the direction, rotation angle data obtained by subtracting 90 ° from the acquired rotation angle is output.

  After the process of step S140, the controller 50 causes the motor drive circuit 72 to move the camera 40 to the center line position that is the position of the movement line on the table 11 by the movement of the table 11 at the laser light irradiation position in step S142. To instruct. In response to this instruction, the motor drive circuit 72 rotates the motor 41 until the movement position data t input from the movement position detection circuit 71 reaches a movement position corresponding to the center line position. In step S144, the camera 40 is instructed to start photographing. In response to this instruction, the camera 40 outputs the image data to the controller 50 at a set cycle, and the controller 50 displays the captured image on the display device 52 based on the input image data.

  After the process of step S144, the controller 50 instructs the feed motor control circuit 62 to move in a direction in which the radius value increases and to move at a high speed in step S146. In response to this instruction, the feed motor control circuit 62 makes the movement speed calculated from the number of pulses per unit time of the pulse signal output from the encoder 13a in the feed motor 13 the movement speed instructed by the controller 50. The feed motor 13 is rotated. As a result, the table 11 moves to the right in FIG. Since the image captured by the camera 40 is displayed on the display device 52 from step S144, each of the steps will be described with reference to FIGS. 6A to 6G showing the state of the image captured by the camera 40. Will be described together with the state of the photographed image.

  After the process of step S146, the controller 50 takes in the image data (pixel brightness data) of the camera 40 in steps S148 to S152, and the number of data whose brightness is less than or equal to a preset brightness in all the image data ( The number of pixels (M) is detected, and the process of determining whether the number of data is greater than or equal to a preset number is repeated. This is a process of detecting the timing at which a circular processing mark appears in the image captured by the camera 40 as shown in FIG. In other words, since the processing trace has a groove shape, the lightness of the part is smaller than the other parts, and at the timing when the circular processing mark appears in the photographed image, the lightness is less than or equal to the preset brightness. Therefore, in step S152, it is possible to detect the timing at which the circular processing trace appears by determining “Yes” for what has been determined to be “No” until then. If it is determined as “Yes” in step S152, the process proceeds to step 154 to instruct the feed motor control circuit 62 to move at a low speed. In response to this instruction, the feed motor control circuit 62 slows the rotation of the feed motor 13. As a result, after the captured image as shown in FIG. 6A appears on the display device 52, the circular processed trace slowly advances toward the center of the captured image. Subsequently, the image data of the camera 40 is taken in steps S156 and S158, and the brightness data of the pixel at the center position (intersection position of the vertical center line and the horizontal center line) of the photographed image is equal to or lower than the preset brightness. The process of determining whether or not As shown in FIG. 6B, this is processing for detecting the timing at which a circular processing mark is applied to the center position of the captured image. That is, when a circular processing mark is applied to the center line position of the photographed image, the brightness data of the pixel at the center position is equal to or lower than the preset brightness, so that it has been determined as “No” until then in step S158. By determining “Yes”, it is possible to detect the timing at which a circular processing mark is applied to the center position of the captured image. If it is determined as “Yes” in step S158, the process proceeds to step 160 to instruct the feed motor control circuit 62 to stop moving. In response to this instruction, the feed motor control circuit 62 stops the rotation of the feed motor 13, and the image taken by the camera 40 stops in the state shown in FIG.

After the process of step S160, the controller 50 fetches the radius value r1 from the radius value detection circuit in step S162, and instructs the feed motor control circuit 62 to move to the position of the radius value (r1 + X1-α) in step S164. To do. In response to this instruction, the feed motor control circuit 62 inputs the radius value r from the radius value detection circuit 63 and rotates the feed motor 13 until the input radius value r becomes equal to the radius value (r1 + X1-α). . Α is a minute value and is set to a value larger than the maximum value of the deviation between the origin of the laser beam irradiation position in the Y direction and the rotation center. X1 is a radius value when a circular processing mark is formed as described above. That is, the radius value (r1 + X1-α) is a radius value at which a linear processing mark is observed on the left side of the horizontal center line of the image captured by the camera 40. In step S166, the controller 50 instructs the motor drive circuit 72 to move the camera 40 to the initial position (the position of the movement position 0 and the drive limit position). In response to this instruction, the motor drive circuit 72 inputs the movement position t from the movement position detection circuit 71 and rotates the motor 41 until the input movement position t becomes equal to zero. Subsequently, in step S168, the controller 50 continues to determine “No” until the radius value r input from the radius value detection circuit 63 reaches the radius value (r1 + X1−α), whereby the radius position indicated by the radius position is indicated. In step S170, the determination is “No” until the movement position t input from the movement position detection circuit 71 becomes 0, thereby waiting for the camera 40 to reach the initial position. When the radius value r becomes the radius value (r1 + X1-α) and the movement position t becomes 0, both the steps S168 and S170 are determined as “Yes”, and the process proceeds to the step S172 in FIG. 3B.

Steps S172 to S176 in FIG. 3B are the same processes as steps S148 to S152 in FIG. 3A. The image data of the camera 40 is taken in, and the number of data (pixels) whose brightness is less than or equal to a preset brightness among all the image data. Number) is a process for detecting M and determining whether the number of data is equal to or greater than a preset number. In step S164, since it is moving to the radius value at which the linear processing mark is observed on the left side of the horizontal center line of the photographed image, it is determined as “Yes” in normal step S176, and the process proceeds to step S180. move on. However, if the deviation between the origin of the laser beam irradiation position in the Y direction and the rotation center is large, there may be a case where a linear processing mark is too far left from the lateral center line of the captured image and does not appear in the captured image. Therefore, if “No” is determined in step S176, the radius value is moved in the direction of increasing in step S176 similarly to step S146, “Yes” is determined in step S176, and the process proceeds to step S180.

Steps S180 to S186 are the same processing as steps S154 to S160, and the linear processing trace is moved toward the center position of the captured image at a low speed, and the linear processing trace is applied to the central position of the captured image. This is the process of stopping the movement. That is, after moving the table 11 at a low speed, the process of determining whether the brightness data of the pixel at the center position of the photographed image is equal to or lower than the preset brightness is repeated, and a linear processing trace is present at the center position. In this case, “Yes” is determined in step S184, and the movement of the table 11 is stopped by instructing the feed motor control circuit 62 to stop moving in step S186. By this processing, the image captured by the camera 40 is in the state shown in FIG.

In the processes of steps S188 to S208, the X-direction position (radius value of the laser beam irradiation position) of the linear machining trace is detected at a plurality of Y-direction positions (movement positions of the camera 40), and the linear machining trace is detected. This is a process of making the direction parallel to the Y direction within an allowable value. First, the controller 50 sets a variable n and a variable m to “1” in step S188. Next, in step S190, the image data of the camera 40 is fetched, and in step S192, the brightness is not more than the set value among the brightness data of the pixels in the vertical direction (Y direction) center line of the photographed image, and the moving direction is the most. The X direction position T of the pixel on the side (the direction side in which the radius value increases) is detected. In step S194, the distance from the X-direction position T to the center position of the captured image is detected and stored as L (m). In this case, since m = 1, L (1). In steps S184 and S186, since the movement of the table 11 is stopped at the timing when the linear processing mark is applied to the center position, L (1) is almost 0, but the movement stop command is issued by the feed motor control circuit. The distance L (1) is detected in consideration of a very short time until the rotation of the feed motor 13 stops. Next, in step S196, it is determined whether m = 5. Since m is still 1, “No” is determined in step S196, and the process proceeds to step S198. In step S198, the controller 50 instructs the motor drive circuit 72 to move the camera 40 to the movement position m · β. In response to this instruction, the motor drive circuit 72 inputs the movement position t from the movement position detection circuit 71 and rotates the motor 40 until the input movement position t reaches the instructed movement position. In this case, since m = 1, the movement position of the camera 40 is β. β is a movement position obtained by subtracting the minimum radius value of the laser light irradiation position from the movement position at the center line position of the camera 40 (the position of the movement line on the table 11 by the movement of the table 11 of the laser light irradiation position). 40 is a value obtained by dividing the movement position when photographing the end of the straight processing trace by the number of L (m) finally obtained (5 in this embodiment). In step S199, m is incremented, and the processes in steps S190 to S196 are performed again. By repeating this process, the value of m increases by 1 and the moving position changes by β, and the distance L (m) from the X-direction position T to the center position of the captured image at each moving position is acquired.

When the value of m reaches 5, it is determined as “Yes” in step S196, and the process proceeds to step S200. By the processing so far, the distances La (1), La (2), La (3), La from the X-direction position T to the moving positions 0, β, 2β, 3β, 4β of the camera 40 to the center position of the photographed image. (4) and La (5) are acquired. If the linear machining trace is completely parallel to the Y direction, La (1) to La (5) are all the same value, but the accuracy when the table 11 is stopped at the rotation angle Θ + 90 ° in step S140. Therefore, there is a possibility that the direction of the linear processing trace is slightly deviated from the Y direction (movement direction of the camera 40). In this case, La (1) to La (5) are values that increase or decrease as the value of m increases. In step S200, the controller 50 calculates an angle formed by the direction of the linear machining trace and the Y direction. Specifically, the coordinates of the X-direction position T at each movement position of the camera 40 are (La (1), 0), (La (2), β), (La (3), 2β), (La ( 4), 3β), (La (5), 4β) are used to calculate a regression equation by the least square method, and an angle Θ1 formed by a straight line represented by this regression equation and a straight line of X = La (1) is calculated. This angle Θ1 is calculated with a sign in which the counterclockwise direction (the rotation direction of the table 11) is the positive direction from the straight line represented by the regression equation. That is, the straight line represented by the regression equation is calculated with a code that is parallel to the Y direction when rotated counterclockwise by the angle Θ1. Next, the controller 50 determines whether or not the absolute value of the angle Θ1 calculated in step S202 is within an allowable value. In step S140, if the table 11 is accurately stopped at the rotation angle Θ + 90 °, the absolute value of the angle Θ1 is determined to be “Yes” within the allowable value, and the process proceeds to step S210. It determines with "No" and progresses to step S202. In step S202, the rotation angle data Θ input from the rotation angle detection circuit 73 is fetched in step S202, and the angle obtained by adding the angle Θ1 calculated in step S200 to the rotation angle Θ fetched in step S204 is the spindle. Output to the motor control circuit 61. In response to this instruction, the spindle motor control circuit 61 rotates the spindle motor 12 at a low speed so that the rotation position of the table 11 is rotated by the rotation angle Θ1. Theoretically, the direction of the linear machining trace should be parallel to the Y direction, so that the camera 40 is returned to the initial position in steps S208 and S209, and the processes in steps S188 to S202 are performed again. By repeating this process, in step S202, the absolute value of the angle Θ1 is within the allowable value, it is determined “Yes”, and the process proceeds to step S210.

In step S210, the controller 50 obtains the distances La (1), La (2), La (3), La from the X-direction position T to the center position of the captured image, which are obtained by the repeated processing of steps S190 to S199. (4), La (5) is averaged and stored as distance L (n). In this case, since n = 1, L (1). In step S212, the radius value r inputted from the radius value detection circuit 63 is taken in and stored as radius data D (n). In this case, since n = 1, D (1). Through the processing so far, data for calculating the X direction position of the point T1 in FIG. 7 is obtained.

After the process of step S212, the controller 50 moves the camera 40 to the motor drive circuit 72 to the center line position (the position of the moving line on the table 11 by the movement of the table 11 at the laser light irradiation position) in step S214 of FIG. 3C. In step S216, the feed motor control circuit 62 is instructed to move to the position of the radius value r1 stored in step S162. In response to this instruction, the motor drive circuit 72 rotates the motor 40 until the movement position t input from the movement position detection circuit 71 reaches the instructed movement position, and the feed motor control circuit 62 receives the radius value detection circuit. The motor 13 is rotated until the radius value r input from 63 reaches the designated radius value. Then, in steps S218 and S220, the controller 50 repeats steps S218 and S220 until the values input from the movement position detection circuit 71 and the radius value detection circuit 63 become instructed values and is determined to be “Yes”. By performing the process, it waits until this movement is completed. The state in which this movement is completed is equal to the state in step S160, and the captured image of the camera 40 is as shown in FIG.

  If it is determined as “Yes” in steps S218 and S220, the controller 50 proceeds to step S222 and increments the variable n to n = 2. Assuming a line formed by the center of the captured image (the center position of the screen in FIG. 6) on the processing object OB when the camera 40 moves in the X direction relative to the table 11 by the processing of steps S224 to S238. The center of the circular processing mark is included in this line. In other words, when the camera 40 is moved in the X direction relative to the table 11, the center of the photographed image passes through the center of the circular processing mark. More specifically, the controller 50 captures image data captured by the camera 40 in step S224, and in step S226, the controller 50 is the most moving direction side (the direction side on which the radius value increases) in the pixels whose brightness is not more than the set value. , The pixel position P on the right side of FIG. 6 is detected. Next, in step S228, whether or not the detected pixel position P is in the vicinity of the upper end of the screen in FIG. 6 (that is, whether or not the pixel position P is below the upper end of the screen by a predetermined small distance γ). In step S232, it is determined whether or not the detected pixel position P is in the vicinity of the lower end of the screen in FIG. 6 (that is, the pixel position P is between the lower end of the screen and a predetermined small distance γ). Or not).

  If the pixel position P is in a position near the upper end of the screen, “Yes” is determined in step S228, and in step S230, the camera 40 is moved in the forward direction (upward on the screen) by a distance half the Y direction of the screen. Direction, which is the direction of the back surface of FIG. If the pixel position P is near the lower end of the screen, “Yes” is determined in step S232, and in step S234, the camera 40 is moved in the negative direction (at the bottom of the screen by a distance half the Y direction of the screen). Direction of the paper surface of FIG. The movement of the camera 40 is performed by the controller 50 taking the movement position data t from the movement position detection circuit 71 and outputting the movement position obtained by adding or subtracting the half distance in the Y direction of the screen to the motor drive circuit 72. Is called. The purpose of performing this processing is when the detected pixel position P is near the upper end or the lower end of the screen, the rotation center is half the screen in the Y direction with respect to the movement line in the X direction of the center of the captured image of the camera 40. This is because there is a possibility of deviation. Specifically, FIG. 6B shows an example in which the pixel position P is in the vicinity of the lower end of the screen. In this case, the camera 40 moves in the negative direction by half the screen, and the pixel position P is in the vicinity of the lower end. To avoid.

  When moving the camera 40, the controller 50 takes in the image data taken by the camera 40 again in steps S224 and S226, detects the pixel position P on the most moving direction side among the pixels whose brightness is not more than the set value, and performs step S228. And determination of step S232 is performed. The processes in steps S224 to S234 are executed until it is determined “No” in both step S228 and step S232, so that the Y-direction position of the rotation center falls within the range (screen) of the captured image of the camera 40. become. If “No” is determined in both step S228 and step S232, the process proceeds to step S236, where the amount of deviation of the pixel position P from the center position in the Y direction is detected in step S236, and the movement position is detected in step S238. The movement position t is input from the circuit 71, and the movement position obtained by subtracting the displacement amount from the movement position t is output to the motor drive circuit 72, so that the pixel position P is in the screen Y direction as shown in FIG. The camera 40 is moved so as to come to the center position. As a result, the movement line in the X direction of the center of the captured image passes through the center of the circular processing mark.

  After the process of step S238, the controller 50 detects the distance from the pixel position P to the center position in the horizontal direction of the screen and stores it as the distance L (n) in step S240. That is, the process of step S240 detects the distance L (n) shown in FIG. 6 (f), which is an enlarged view of the portion surrounded by the alternate long and short dash line in FIG. 6 (e). As can be understood from the above description, the pixel position P indicating the position where the circular processing mark is closest to the moving direction is slightly shifted from the center position of the screen to the moving direction (right side of the screen). Because. In step S242, the radius value r is input from the radius value detection circuit 63, and the input radius value r is stored as radius data D (n). In this case, since n = 2, L (2) and D (2). By the processing so far, data for calculating the X direction position of the point P in FIG. 7 is obtained.

  After the process of step S242, the controller 50 increments the variable n to n = 3 in step S244 of FIG. 3D, and executes the processes of steps S246 to S260. This process is the same as the process of steps S146 to S160 described above, and when the table 11 is moved at a high speed to the side where the radius value r is increased, a processing trace enters the captured image (in the screen) of the camera 40. In this process, the movement speed of the table 11 is lowered, and the movement of the table 11 is stopped when the processing mark comes to the center position of the photographed image of the camera 40. In this case, since the processing mark is included in the captured image of the camera 40 at the time when the high-speed movement is started in step S246, the controller 50 performs the process of step S246 and then the captured image of the camera 40. After a minute time has passed since there is no processing trace from the inside, the process proceeds to step S248. As shown in FIG. 7, when the shooting position of the camera 40 moves in the X direction from the point P, the processing trace will next enter the shot image of the camera 40 at the point T2, so at the stage where the processing of S260 is completed. The photographed image of the camera 40 is as shown in FIG.

  After the process of step S260, the controller 50 takes in image data input from the camera 40 in step S262, and in step S264, the brightness data of the pixels on the center line in the vertical direction of the image (screen) taken by the camera 40 Among the following, the pixel position T closest to the moving direction (the side on which the radius value r increases) is detected. In this process, unlike the above-described steps S226 to S238, the process of moving the pixel position P to the center position in the Y direction (vertical direction) of the screen is not performed. This is because the line formed by the imaging center when the camera 40 is moved in the X direction passes through the center (rotation center) of the circular processing trace. In this case, the pixel position T is used instead of the pixel position P, but these pixel positions T and P are substantially the same. Then, the controller 50 stores the difference between the detected pixel position T and the screen center position as the distance L (n) by the processing in steps S266 and S268 similar to the above-described steps S240 and 242 and the radius value r as the radius. Store as data D (n). In this case, since n = 3, L (3) and D (3). In this case, since the movement of the table 11 is stopped when the processing mark reaches the center position of the captured image of the camera 40, L (3, which is the distance from the center position of the captured image to the pixel position T. ) Is a value close to 0, but even if the table 11 is moved at a low speed, it takes a little time until the stop command is output after the image data is processed. As with the data acquisition of L, data of L (n) is acquired.

After the processing in step S268, the controller 50 instructs the camera 40 to stop photographing in step S270. Next, the controller 50 uses the radius data D (2), D (3) and the distance data L (2), L (3) in step S272 to set the radius R of the circular machining trace according to the following equation 4. calculate. In step S274, the radius data D (1), D (2), distance data L (1), L (2), and the radius R of the circular machining trace calculated in step S272 are According to 5, the distance De from the center O2 of the circular machining trace to the linear machining trace is calculated.

  A few explanations are added to these equations 4 and 5. The radius data D (1) to D (3) are the radius value data detected by the radius value detection circuit 63 when there is a processing mark near the center of the shooting screen of the camera 40 at points T1, P, T2 in FIG. However, the center of the photographing screen of the camera 40 and the points T1, P, T2 do not coincide with each other, and the deviation is represented by the distance data L (1) to L (3). Since the points T1, P, and T2 are on the moving direction side (the side on which the radius value r increases and the right side of the shooting screen) from the center of the shooting screen of the camera 40, the points T1, P, and T2 are located on the camera 40. In order to match the center of the shooting screen, it is necessary to move the table 11 to the opposite side of the moving direction by the amount of deviation represented by the distances L (1) to L (3). That is, the position in the X direction when the points T1, P, and T2 coincide with the center of the shooting screen of the camera 40 is obtained from the distance data L (1) to L (3) from the radius data D (1) to D (3). Subtracted value. The right side of FIG. 7 is the moving direction side, and the value on the X direction position increases as the point is on the left side of FIG. 7. Therefore, the distance indicated by the arrow in FIG. Can be obtained by subtracting the X direction position of the point P from the X direction position of the point T1. Then, if R and De at the distance indicated by the arrow in FIG. 7 are used as expressions on the left side, Expressions 4 and 5 are obtained.

  After the process of step S274, the controller 50 performs rotation when the coordinate value of the origin position O1 is (0, 0) using the radius position X1 and the calculated radius R and distance De in step S276. The coordinate value (x, y) of the center O2 is calculated according to the equations 1 and 3 described above. Next, the controller 50 displays the coordinate value (x, y) of the rotation center O2 on the display device 52 in step S278, and ends the execution of the program in step S280.

  After the execution of this program, the operator manually operates the micrometer 34 to move the machining head 20 in the direction perpendicular to the paper surface by the y coordinate of the rotation center. Further, the initial value set in the radius value detection circuit 63 is corrected so that the radius value becomes smaller by the x coordinate of the rotation center by executing a program (not shown) or an operation by the operator. Further, after the execution of the program, the machining head 20 is automatically moved in the vertical direction of the paper by the y coordinate of the rotation center by the automatic execution of another program, and is set in the radius value detection circuit 63. The initial value may be modified so that the radius value becomes smaller by the x coordinate of the rotation center. In this case, an actuator capable of automatically moving the machining head 20 is required instead of the micrometer 34. Thereby, the origin position in laser beam irradiation can be made to correspond with an actual rotation center.

  According to the embodiment operating as described above, even if the laser processing apparatus has a structure in which the laser beam cannot be moved to the origin position in the laser beam irradiation, the deviation amount between the origin position and the rotation center in the laser beam irradiation. Can be measured. And since the origin position in laser beam irradiation can be moved using this deviation | shift amount, the origin position and rotation center in laser beam irradiation can be made to correspond. Moreover, since the laser processing apparatus can be calculated only by providing the camera 40 and the camera moving means (motor 41), the relationship between the origin position and the rotation center in the laser light irradiation can be calculated, so that the cost increase of the laser processing apparatus can be suppressed. .

b. Second Embodiment In the first embodiment, the direction of the linear machining trace is made to coincide with the Y direction (the movement direction of the camera 40) with high accuracy, and then the point on the linear machining trace and the circular machining trace is determined. The X direction positions of T1, P, and T2 are detected, and the radius R of the circular machining trace and the distance De from the center O2 of the circular machining trace to the linear machining trace are obtained. The radius R and the distance De are calculated. Any method may be used as long as it can be obtained. In the second embodiment, the radius R and the distance De are obtained by detecting the coordinate values of three points with different circular machining traces and the coordinate values of two points with different linear machining traces. It is. The overall configuration diagram of the laser processing apparatus according to the second embodiment is the same as that of the first embodiment. The difference from the first embodiment is that the controller 50 executes the origin position and the processing object OB in laser light irradiation. This is only a deviation measurement program for obtaining a deviation from the rotation center. Therefore, the origin position in the laser light irradiation performed after the operator performs the work such as setting of the workpiece OB performed before the controller 50 executes the deviation measurement program and the deviation measurement program is executed. The adjustment work to match is the same as in the first embodiment.

  Hereinafter, in 2nd Embodiment, it demonstrates along the shift | offset | difference measurement program which the controller 50 performs. The execution of the deviation measurement program is started in step S300 in FIG. 8A. The processing from step S302 to step S344 is the same processing as step S102 to step S144 in the first embodiment, and forms a circular processing trace and a linear processing trace on the processing object OB, and a linear processing trace. Is a process of starting camera shooting with the camera approximately parallel to the Y direction. In step S342, the reason why C1 is added to the center line position is that the value of the center line position C1 is used in the calculation process described later.

  The processing from step S346 to step S408 is processing for detecting the coordinate values of three points with different circular machining traces and the coordinate values of two points with different linear machining traces. The coordinate value is obtained by acquiring the X direction position and the Y direction position when the processing mark is displayed on the captured image of the camera 40. As in the first embodiment, the X-direction position is calculated from the radius data acquired from the radius value detection circuit 63 and the distance data calculated from the pixel position of the captured image of the camera 40. The Y-direction position is calculated from two pieces of movement position data acquired from the movement position detection circuit 71 and distance data calculated from the pixel position of the captured image of the camera 40. Three different points on the circular machining trace and two different points on the linear machining trace may be arbitrary, but in this embodiment, P1 shown in FIG. 9 is used in order to reduce the movement of the table 11 and the movement of the camera 40. Coordinate values at 5 points of P5 are detected.

  After the camera 40 starts shooting in step S344, the controller 50 sets the variable n to 1 in step S346 of FIG. 8B. The variable n indicates the five points P1 to P5 of the processing marks by the numbers. Next, the processing of steps S348 to S362 moves the table 11 to the side where the radius value r becomes larger, so that a circular processing mark is displayed near the center of the camera photographed image. This process is the same as the process of steps S146 to S160 of the first embodiment. The table 11 is moved at a high speed to the side where the radius value r is increased, and a processing trace is present in the captured image (in the screen) of the camera 40. Upon entering, the movement speed of the table 11 is reduced, and the movement of the table 11 is stopped when the processing trace reaches the center position of the captured image of the camera 40. As a result, the processing trace at point P1 in FIG. 9 is displayed near the center of the captured image. It should be noted that at the time when high-speed movement is started in the case of n = 2 or later to be described later, there may be a processing mark in the captured image of the camera 40. Therefore, after performing the process of step S348, the camera 40 After a lapse of a minute time when there is no processing trace in the captured image, the process proceeds to step S350.

  After the processing trace is displayed in the vicinity of the center of the photographed image in step S362, the controller 50 determines the center line in the Y direction (vertical direction) of the photographed image (screen) from the image data captured in step S358 in step S364. Is extracted, and the pixel position is the most moving direction (the radius value r is the larger side and the right side of the screen) and the pixel position is the most moved. The position of a pixel on the opposite side of the direction (the side on which the radius value r decreases and the left side of the screen) is detected, and the intermediate position between the two pixel positions from the center of the captured image (the captured image at point P1 in FIG. 9). The distance Lx (n) to the upper position) is detected and stored. In the present embodiment, the distance Lx (n) represents the left direction of the screen as positive and the right direction as negative. However, in this case, the right end of the processing trace is near the center of the captured image of the camera 40, so the distance Lx (n) is positive. Value. Next, in step S366, radius value data D (n) is stored in the same process as in steps S212, S242, and S268 of the first embodiment. Through the processing so far, data for calculating the coordinate value at the point P1 in FIG. 9 is obtained. Since n = 1, the obtained data is Lx (1), D (1).

  After the process of step S364, the controller 50 instructs the motor drive circuit 72 to move the camera 40 to the moving position C2 (center line position−minimum radius position of laser light irradiation−α) in step S368, In step S370, the moving position detection circuit 71 receives the moving position data t and waits until the movement is completed and “Yes” is determined. Α is a minute value and is set to a value larger than the maximum value of the deviation between the origin of the laser beam irradiation position in the X direction and the rotation center. And (center line position-minimum radius position of laser beam irradiation) is a linear processing mark near the center of the captured image of the camera 40 when the X direction position of the camera 40 is set to the position of the linear processing mark. This is the position near the end of That is, the position of (center position−minimum radius position of laser light irradiation−α) is linear in the vicinity of the center of the captured image of the camera 40 when the X-direction position of the camera 40 is set to the position of the linear processing mark. This is a position where a straight machining trace is displayed without fail near the end of the machining trace.

  After determining “Yes” in step S370, the controller 50 determines whether the variable n is 3 in step S372. In this case, since the variable n is 1, the determination is “No” and the process proceeds to step S374. In step S374, the variable n is incremented to n = 2, and the processes of steps S348 to S372 are performed again. In this case, what is displayed near the center of the photographed image of the camera 40 is the point P2 in FIG. 9 of the linear processing trace, and the controller 50 calculates the coordinate value at the point P2 in steps S364 and S366. Lx (2) and D (2) are stored as data for this purpose. In this case as well, Lx (2) is a positive value because the right end of the processed trace is in the vicinity of the center of the captured image of the camera 40. In S368, the camera 40 is instructed to move to the moving position of (center line position−minimum radius position of laser light irradiation−α), but since it is already at that position, “Yes” is immediately entered in step S370. And the process proceeds to step S372.

  When it comes to step S372 again, the controller 50 determines whether the variable n is three. In this case, since the variable n is 2, it is determined as “No” again, and the process proceeds to step S374. In step S374, the variable n is incremented to n = 3, and the processes of steps S348 to S372 are performed again. In this case, what is displayed near the center of the captured image of the camera 40 is a point P3 in FIG. 9 of a circular processing trace, and the controller 50 calculates the coordinate value at the point P3 in steps S364 and S366. Lx (3) and D (3) are stored as data for this purpose. In this case as well, Lx (3) is a positive value because the right end of the processed trace is in the vicinity of the center of the captured image of the camera 40. In S368, the camera 40 is instructed to move to the moving position of (center line position−minimum radius position of laser light irradiation−α), but since it is already at that position, “Yes” is immediately entered in step S370. And the process proceeds to step S372.

  When it comes to step S372 again, the controller 50 determines whether the variable n is three. In this case, since the variable n is 3, it is determined as “Yes”, and the process proceeds to step S376 in FIG. 8C. The variable n is incremented to n = 4. It is instructed to move to (movement position 0, drive limit position). In step S380, the feed motor control circuit 62 is instructed to move the table 11 to the position represented by the radius value D (2) stored in step S366 when n = 2. Then, in steps S382 and S384, the movement position data t input from the movement position detection circuit 71 and the radius value data r input from the radius value detection circuit 63 become the specified values and are determined as “Yes”. Wait for the move to complete.

  In a state where “Yes” is determined in step S384, the point P4 in FIG. 9 of the linear processing trace is displayed near the center of the captured image of the camera 40. In subsequent step S386, the controller 50 performs the same processing as that in step S364, and detects and stores the distance Lx (4) from the center of the captured image to the position on the captured image at point P4 in FIG. As described above, the distance Lx (n) represents that the left direction of the screen is positive and the right direction is negative. Therefore, the point P4 is positive if it is on the left side from the center on the photographed image, and negative if it is on the right side. A sign is attached. If the 90-degree rotation of the table 11 in step S340 is performed accurately, the captured image of the camera 40 is the same as that at the point P2 in FIG. May be added. Since the position is moved to the position represented by the radius value D (2) in step S380, D (4) is equal to D (2), and the data for calculating the coordinate value at the point P4 is Lx It is only necessary to acquire (4).

  After the process of step S386, the controller 50 increments the variable n to n = 5 in step S388, and performs the processes of steps S390 to S404. This process is a process in which the moving direction is reversed from the processes in steps S348 to S362, and the table 11 is moved at a high speed to the side where the radius value r becomes smaller, so that it is within the captured image (in the screen) of the camera 40. When the processing trace enters, the movement speed of the table 11 is reduced, and the movement of the table 11 is stopped when the processing trace reaches the center position of the image captured by the camera 40. When the processing in step S404 ends, what is displayed near the center of the captured image of the camera 40 is a point P5 in FIG. In this case, since the circular processed trace moves from the right side of the captured image toward the center and stops at the timing when the boundary between the processed trace and the non-processed trace is applied to the center of the captured image, the point P5 in FIG. 9 is captured. Located below the center of the image. The reason for determining the point P5 only in the Y direction (vertical direction of the screen) is to determine the point P5 on the smaller processing trace width and improve the detection accuracy of the distance Lx (n), but other points P1. As in the case of P4, it may be determined in the X direction (the horizontal direction of the screen).

  After the process of step S404, the controller 50 extracts the brightness data of the pixel in the X direction (lateral direction) center line of the photographed image from the image data captured in step S400 in step S406, and the brightness is a set value. In the following, the position of the pixel whose pixel position is on the uppermost side of the screen (the side where the moving position t becomes larger) and the position of the pixel whose pixel position is the lowermost side of the screen (the side where the moving position t becomes smaller) are detected. The distance Ly from the center of the captured image to the intermediate position of these two pixel positions (the position of the point P5 in FIG. 9 on the captured image) is detected and stored. Since the position of the point P5 in FIG. 9 on the photographed image is determined to be below the center of the photographed image, it is not necessary to add a reference numeral. Subsequently, in step S408, the radius value data D (n) is stored in the same process as in step S366. Thereby, Ly and D (5) are obtained as data for calculating the coordinate value at the point P5.

After the processing in step S408, the controller 50 instructs the camera 40 to stop photographing in step S410 in FIG. 8D, and in step S412, the circular processing trace is recorded using the coordinate values of the points P1, P3, and P5. The center coordinates (x0, y0) and the radius R of the circular machining trace are calculated. The coordinate values of the points P1, P3, and P5 are the following values, and can be calculated using the data acquired in the processing so far and the set moving position.
Point P1: [{D (1) + Lx (1)}, C1]
Point P3: [{D (3) + Lx (3)}, C2]
Point P5: [D (5), 0-Ly]
This calculation may be obtained by solving simultaneous equations formed by substituting coordinate values into a circle formula, or by obtaining the coordinates of the intersection of two perpendicular bisectors of two points as the center coordinates of the circle. You may obtain | require the distance from a coordinate to each point as a radius value.

After the process of step S412, the controller 50 calculates an equation of the straight line A passing through the points P2 and P4, which is the center line of the linear processing trace, using the coordinate values of the points P2 and P4 in step S414. The equation of the straight line B that passes through the center coordinates (x0, y0) of the circular machining trace calculated in step S408 and is perpendicular to the straight line A is calculated, and the intersection coordinates (xs, ys) of the straight line A and the straight line B are calculated. calculate. The coordinate values of the points P2 and P4 are the following values, and can be calculated using the data acquired in the process so far and the set movement position.
Point P2: [{D (2) + Lx (2)}, C2]
Point P4: [{D (4) + Lx (4)}, 0]

  After the processing of step S414, the controller 50 calculates the distance between the center coordinates (x0, y0) of the circular machining trace and the intersection coordinates (xs, ys) of the straight line A and the straight line B in step S416. If x0> xs, a plus sign is added, and if x0 <xs, a minus sign is added to obtain the distance De from the center O2 of the circular machining trace to the linear machining trace. Subsequently, in step S418, the coordinates of the rotation center O2 when the coordinate value of the origin position O1 is (0, 0) using the radius R and the distance De by the same process as in step S276 in the first embodiment. Calculate the value (x, y). Then, in step S420, the coordinate value (x, y) of the rotation center O2 is displayed on the display device 52, and the execution of the program is terminated in step S422.

  After the execution of this program, if the operator performs the same operation as in the first embodiment, the origin position in the laser beam irradiation can be made coincident with the actual rotation center. The same effect as that of the first embodiment can also be obtained by the second embodiment that operates as described above. That is, even in a laser processing apparatus having a structure in which laser light cannot be moved to the origin position in laser light irradiation, a deviation amount between the origin position and the rotation center in laser light irradiation can be measured. And since the origin position in laser beam irradiation can be moved using this deviation | shift amount, the origin position and rotation center in laser beam irradiation can be made to correspond. Moreover, since the laser processing apparatus can be calculated only by providing the camera 40 and the camera moving means (motor 41), the relationship between the origin position and the rotation center in the laser light irradiation can be calculated, so that the cost increase of the laser processing apparatus can be suppressed. .

  The first and second embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the object of the present invention. Is possible.

そして、前記数６及び数７に基づいて、回転中心Ｏ２の座標値ｘ，ｙを計算すると、座標値ｘ，ｙは下記数８及び数９で表される。

よって、２つの円形の加工跡を形成するときの半径位置を記憶しておき、形成された２つの円形の加工跡の半径を測定すれば、数８および数９から原点位置の座標値を(０，０)としたときの回転中心の座標値(ｘ，ｙ)を計算することができる。なお、数９により計算されたｙは、本実施形態の数１で計算されたｙより精度が落ちるので、平均値またはメジアン値の計算の際に除外してもよい。 In the first embodiment and the second embodiment, only one circular machining trace is created. However, two or more circular machining traces are created by changing the radius value. Calculate the distance De from the center to the straight machining trace, calculate the coordinate value (x, y) of the rotation center when the coordinate value of the origin position is (0, 0), and average the values Alternatively, the median value may be obtained. In addition, the coordinate value (x, y) of the rotation center when the coordinate value of the origin position is (0, 0) can be calculated using the radius R in the circular machining traces of two different radii. The average value or the median value may be obtained by adding the value. This calculation method will be described below. As shown in FIG. 10, the origin position of the laser light irradiation is “O1”, its coordinate value is (0, 0), the rotation center of the table 11 is “O2”, and its coordinate value is (x, y). . The radius positions when two circular machining traces are formed by laser light irradiation are X1 and X2, respectively, and the radii of the two circular machining traces formed are R1 and R2. At this time,
The following Equation 6 and Equation 7 are established.

Then, when the coordinate values x and y of the rotation center O2 are calculated based on the equations 6 and 7, the coordinate values x and y are expressed by the following equations 8 and 9.

Therefore, if the radius positions when forming two circular machining traces are stored and the radii of the two circular machining traces formed are measured, the coordinate value of the origin position can be obtained from (8) and (9) as ( The coordinate value (x, y) of the rotation center when 0, 0) can be calculated. Note that y calculated by Equation 9 is less accurate than y calculated by Equation 1 in the present embodiment, and may be excluded when calculating the average value or the median value.

  In the first embodiment, the fine adjustment is performed when the angle formed by the linear processing trace with the Y direction is equal to or larger than the allowable value. However, if the table 11 can be rotated 90 degrees with high accuracy, high accuracy is achieved. If this is not necessary, such fine adjustment may not be performed. That is, after creating a linear machining trace, the table 11 may be rotated by 90 degrees to detect the X-direction position at an arbitrary point of the linear machining trace. According to this, the coordinate value (x, y) of the rotation center when the coordinate value of the origin position is (0, 0) in a shorter time can be obtained.

  Further, in the first embodiment, the table 11 is moved with the linear machining trace parallel to the Y direction to detect the X direction position of each point of the machining trace, but the camera 40 can be moved instead. The range is at least from the end of the circular machining trace to the opposite end, and the linear machining trace is in a state in which the machining trace is created, that is, parallel to the X direction, and the camera 40 is moved to move each of the machining traces. You may make it detect the Y direction position of a point. Also by this, the same effect as the first embodiment can be obtained.

  In the second embodiment, the coordinate value of each point of the machining trace is detected by moving the table 11 with the camera 40 positioned in three positions (Y direction position) C1, C2, 0 (origin position). However, the camera 40 and the table 11 may be moved in any way as long as the coordinate values of three or more circular processing traces and two or more linear processing traces can be obtained. For example, after creating a linear machining trace, the coordinates of the two points of the circular machining trace are obtained by moving the table 11 in a direction in which the radius value increases with the position of the camera 40 slightly shifted from the center line position. Detect value. Next, the X direction position of the table 11 is fixed at two positions, and the camera 40 is moved from the initial position to a position beyond the center line position, so that one point of the circular processing trace and the linear processing trace are detected. The coordinate values of the two points may be detected.

  Moreover, in the said 1st Embodiment and 2nd Embodiment, although the controller 50 acquired the radius value R and the distance De by executing a program, the controller 50 executes a program with a circular process trace and a straight line. 3A to FIG. 3A to FIG. 3A to FIG. 3A to FIG. 3A to FIG. The radius value R and the distance De may be obtained in the same manner as when the program of 3D or FIGS. 8A to 8D is executed. The same effect can be obtained by this.

  Moreover, in the said 1st Embodiment and 2nd Embodiment, although the camera 40 was provided as a means to observe a process trace in a laser processing apparatus, the moving mechanism (motor 41) of the camera 40 and the camera 40, and the circuit for moving After forming a circular processing mark and a linear processing mark on the processing object OB, the processing object OB is removed from the table 11 and the circular processing mark formed on the processing object OB is enlarged and observed. In addition, it is set in a device (for example, a high-precision microscope) that can be moved while detecting the movement position of the observation point, and in the same manner as when the program is executed, the X direction of each point on the processing trace The position or coordinate value may be obtained to obtain the radius value R and the distance De. The same effect can be obtained by this.

  Moreover, in the said 1st Embodiment and 2nd Embodiment, although the controller 50 performs the laser processing for forming a circular processing trace and a linear processing trace, The movement, rotation, and laser processing of the table 11 may be performed by inputting from the input device 51. The same effect can be obtained also by this.

  Further, in the first embodiment, in order to obtain the radius of the circular machining trace and the distance from the linear machining trace to the circular machining trace, the position of the boundary point on the moving direction side in the width of the machining trace is determined. Although it was performed by detecting, the position of the center in the width of the machining trace may be detected, or the position of the boundary point on the opposite side to the moving direction may be detected.

  Furthermore, in the first embodiment and the second embodiment, in order to obtain the X-direction position or coordinate value of each point of the processing trace, the value output from the radius value detection circuit and the captured image data of the camera are processed. The inter-pixel distance obtained in (1) was used. However, instead of this, the movement of the table 11 is controlled so that each point of the processing trace accurately comes to the center position of the photographed image of the camera, and only the value output by the radius value detection circuit is used. May be.

DESCRIPTION OF SYMBOLS 11 ... Table, 12 ... Spindle motor, 13 ... Feed motor, 15 ... Screw rod, 16 ... Support stand, 20 ... Processing head, 34 ... Micrometer, 40 ... Camera, 41 ... Motor, 50 ... Controller, 51 ... Input device 52 ... Display device 63 ... Radius value detection circuit 65 ... Light emission signal supply circuit

Claims (8)

A table for setting the workpiece,
Rotating means for rotating the table;
A processing head for irradiating a processing target set on the table with a laser beam;
A laser beam moving unit that moves the irradiation position of the laser beam irradiated by the processing head on a line that is in the vicinity of the rotation center of the table by the rotating unit and includes the origin position in the laser beam irradiation;
A laser light irradiation position adjusting means for adjusting a laser light irradiation position in a direction perpendicular to a moving direction of the laser light by the laser light moving means;
In a laser processing apparatus comprising: a distance detection unit that detects a distance from the origin position to a laser beam irradiation position on the line that is moved by the laser beam moving unit;
The laser beam moving unit is controlled using the distance detected by the distance detecting unit, and the laser beam irradiation position is moved from the origin position to a position having a preset distance. In the state of being moved, the rotating means is controlled to rotate the processing object set on the table, and the processing object is irradiated with laser light from the processing head, so that the processing object is circular. A circular processing mark forming means for forming
While moving the irradiation position of the laser beam by the laser beam moving means, the processing object set on the table is irradiated with the laser beam from the processing head to form a linear processing mark on the processing object. Straight machining trace forming means;
A processing diameter measuring means for observing the surface of the processing object set on the table and measuring the radius of the circular processing trace;
Center-straight line distance measuring means for observing the surface of the workpiece set on the table and measuring the distance between the center of the circular machining trace and the linear machining trace;
The radius of the measured circular processing trace, the distance between the center of the measured circular processing trace and the linear processing trace, and the irradiation position of the laser beam when forming the circular processing trace And a deviation amount calculating means for calculating a deviation amount of the origin position with respect to an actual rotation center by the rotating means using a preset distance which is a distance from the origin position. Processing equipment. The laser processing apparatus according to claim 1,
The circular machining trace forming means moves the irradiation position of the laser beam from the origin position to two different positions which are a first distance and a second distance set in advance, respectively, and the machining positions are formed at two different positions, respectively. Forming a first circular machining trace and a second circular machining trace on the object;
The processing diameter measuring means measures a radius at the first circular processing trace and the second circular processing trace,
The deviation amount calculation means includes a radius between the measured first circular machining trace and a second circular machining trace, and a distance between the measured circular machining trace center and the linear machining trace. And the first distance and the second distance, which are distances from the origin position of the irradiation position of the laser beam when forming the first and second circular processing marks, by the rotating means. A laser processing apparatus for calculating a deviation amount of the origin position with respect to an actual rotation center. In the laser processing apparatus according to claim 1 or 2,
A camera for magnifying and photographing a workpiece set on the table;
Camera moving means for moving the camera in the same direction as the laser light moving direction by the laser light irradiation position adjusting means;
A rotation position control means for controlling the rotation position of the table by controlling the rotation start and stop of the rotation means;
With
The laser beam moving means moves the table and the rotating means while fixing the processing head,
The processing diameter measuring means moves the photographing location of the camera by the camera moving means and the laser light moving means, and from the image photographed by the camera in the moving direction by the laser light moving means, Detect the shooting location where the distance between the processing traces is the maximum distance, calculate the radius of the circular processing trace from the distance between the processing traces of the circular processing trace in the imaging location,
When the camera is moved by the camera moving unit, the center-straight line distance measuring unit matches a moving direction of the camera with a linear direction of the linear processing mark taken by the camera. As described above, in a state where the rotational position of the table is controlled by the rotational position control means, the photographing position of the camera is moved by the camera moving means and the laser light moving means, and the laser light movement is performed from the image photographed by the camera. Detecting a shooting location where the distance between the linear processing trace and the circular processing trace is the maximum distance in the moving direction by the means, and the distance between the linear processing trace and the circular processing trace at the imaging location and the processing diameter The distance between the center of the circular machining trace and the linear machining trace is calculated from the radius of the circular machining trace calculated by the measuring means. . In the laser processing apparatus according to claim 1 or 2,
A camera for magnifying and photographing a workpiece set on the table;
Camera moving means for moving the camera in the same direction as the laser light moving direction by the laser light irradiation position adjusting means;
Camera moving position detecting means for detecting a moving position of the camera by the camera moving means;
With
The laser beam moving means moves the table and the rotating means while fixing the processing head,
The processing diameter measuring means moves the photographing location of the camera by the camera moving means and the laser light moving means, and at least three different circular processing traces at predetermined positions of the image photographed by the camera. Coordinate values are calculated using the camera movement position detected by the camera movement position detection means and the distance detected by the distance detection means when each location is photographed, and from the calculated at least three coordinate values. Calculate the radius of the circular machining trace,
The center-straight line distance measuring means moves the photographing location of the camera by the camera moving means and the laser beam moving means, and the linear processing trace is located at a predetermined position of the image photographed by the camera. Coordinate values are respectively calculated using the camera movement position detected by the camera movement position detection means and the distance detected by the distance detection means when at least two different locations are photographed, and the calculated at least 2 From the two coordinate values, a straight line expression of the straight machining trace is calculated, the center coordinates of the circular machining trace are calculated from three or more coordinate values calculated by the machining diameter measuring means, and the calculated straight line A laser processing apparatus for calculating a distance between a center of a circular processing trace and a linear processing trace from an equation and the calculated center coordinates of the circular processing trace. A table for setting the workpiece,
Rotating means for rotating the table;
A processing head for irradiating a processing target set on the table with a laser beam;
A laser beam moving unit that moves the irradiation position of the laser beam irradiated by the processing head on a line that is in the vicinity of the rotation center of the table by the rotating unit and includes the origin position in the laser beam irradiation;
A laser light irradiation position adjusting means for adjusting a laser light irradiation position in a direction perpendicular to a moving direction of the laser light by the laser light moving means;
Applied to a laser processing apparatus having a distance detecting means for detecting a distance from the origin position to a laser beam irradiation position on the line moved by the laser light moving means, and correcting the origin position in laser light irradiation In the method of correcting the origin of the laser processing apparatus,
The laser beam moving unit is controlled using the distance detected by the distance detecting unit, and the laser beam irradiation position is moved from the origin position to a position having a preset distance. In the state of being moved, the rotating means is controlled to rotate the processing object set on the table, and the processing object is irradiated with laser light from the processing head, so that the processing object is circular. A circular processing mark forming step to form
While moving the irradiation position of the laser beam by the laser beam moving means, the processing object set on the table is irradiated with the laser beam from the processing head to form a linear processing mark on the processing object. Straight line trace formation process;
A processing diameter measuring step of observing the surface of the processing target set on the table and measuring the radius of the circular processing trace,
A center-straight line distance measuring step of observing the surface of the workpiece set on the table and measuring the distance between the center of the circular processing trace and the linear processing trace;
The radius of the measured circular processing trace, the distance between the center of the measured circular processing trace and the linear processing trace, and the irradiation position of the laser beam when forming the circular processing trace A deviation amount calculating step of calculating a deviation amount of the origin position with respect to an actual rotation center by the rotation means, using a preset distance which is a distance from the origin position;
An origin correction method for a laser processing apparatus, comprising: an origin position changing step of changing an origin position in laser light irradiation by the calculated deviation amount. In the origin correction method of the laser processing apparatus according to claim 5,
In the circular machining mark forming step, the irradiation position of the laser beam is moved from the origin position to two different positions, which are a first distance and a second distance set in advance, and the machining object is respectively obtained at two different positions. Forming a first circular machining trace and a second circular machining trace on the object;
The machining diameter measuring step measures a radius at the first circular machining trace and the second circular machining trace,
The deviation amount calculating step includes a radius between the measured first circular machining trace and the second circular machining trace, and a distance between the measured circular machining trace and the linear machining trace. And the first distance and the second distance, which are distances from the origin position of the irradiation position of the laser beam when forming the first and second circular processing marks, by the rotating means. An origin correction method for a laser processing apparatus, comprising: calculating a deviation amount of the origin position with respect to an actual rotation center. In the origin correction method of the laser processing apparatus according to claim 5 or 6,
The origin changing step adjusts the irradiation position of the laser beam using the laser beam irradiation position adjusting means based on the calculated deviation amount, and corrects the origin position on the line. Origin correction method for laser processing equipment. In the method for correcting the origin of the laser processing apparatus according to any one of claims 5 to 7,
In the processing diameter measurement step, the observation target is magnified while moving the observation point and the position of the observation point is measured, and the radius of the circular processing mark is calculated from the position of the measured observation point,
In the center-straight line distance measuring step, the object to be processed is enlarged and observed while moving the observation point, and the position of the observation point is measured. An origin correction method for a laser processing apparatus, characterized by measuring a distance from a linear processing mark.

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