JP2010064181A - Fixture-coordinate specification method for machining apparatus, and machining apparatus using the method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fixture-coordinate specification method, for a machining apparatus on which the coordinate position of a fixture is measured with a touch sensor, capable of improving its measurement accuracy and resulting machining accuracy as well, and to provide the machining apparatus using the method. <P>SOLUTION: The method includes: a first step (s1) to measure the coordinate position of a master ring with a spindle holding a tester; a second step (s2) to measure the coordinate position of the master ring with the spindle holding a touch sensor; a third step (s3) to calculate a difference between both of the coordinate positions; a fourth step (s4) to set the difference as a correction value for a value measured by the touch sensor; a fifth step (s5) to measure the coordinate position of the fixture using the touch sensor; and a sixth step (s6) to correct the measured coordinate position based on the correction value and set the result as the coordinate position of the fixture. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a jig coordinate identification method for a machining apparatus and a machining apparatus using the method, and more particularly, to an apparatus for identifying a jig coordinate position by a touch sensor held by a spindle.

  For example, in the production of vehicle parts such as engine and transmission cases, these are processed from multiple directions by a processing device. These machining parts include, for example, a machining table that rotates around a center line extending in the vertical direction with a jig for holding a workpiece mounted thereon, and a spindle that rotates a machining tool around the center line extending in the horizontal direction. Are machined by a machining device (machining center).

  For these processes, the workpiece is held by a jig at a predetermined processing position with respect to the machining center. For example, the workpiece is arranged at a predetermined processing position in the machine coordinate system of the machining center, and is held by a jig so as not to move from the position.

  In the case of the above-described machining center, an XYZ coordinate system in which the rotation center line direction of the machining tool extending in the horizontal direction is the Z-axis direction, the vertical direction is the Y-axis direction, and the direction orthogonal to the Z-axis and the Y-axis is the X-axis direction. Have.

By the way, in recent years, before processing a workpiece, the coordinate position of a jig is detected using a touch sensor as disclosed in, for example, Patent Document 1 below, and the detected coordinate position data and a predetermined jig arrangement are detected. A deviation amount from the position coordinates is calculated, and the machining data is corrected based on the calculated deviation amount. Thereby, even if the jig is displaced from the predetermined arrangement position, the processing apparatus can process the workpiece with high accuracy by the correction.
JP 2005-288593 A

  However, the touch sensor described above is easily bent due to contact with a detection target (for example, a jig) because the probe constituting the detection head is formed long and thin, and when the probe is bent. The detection result may be shifted. For this reason, the reliability of the detection accuracy of the touch sensor is not necessarily sufficient, and the coordinate position of the jig cannot be accurately identified only by measuring the coordinate position using the touch sensor. There was a possibility of incurring a decrease in accuracy.

  This invention measures the coordinate position of a jig using a touch sensor, improves the measurement accuracy and, as a result, improves the processing accuracy, and a jig coordinate specifying method for a processing apparatus, and its method An object is to provide a processing apparatus using the method.

  The jig coordinate specifying method of the present invention includes a first step in which a master ring is fixed to a jig of a processing apparatus, a tester is gripped by a spindle, and the coordinate position of the master ring is measured. A second step of fixing the master ring and holding the touch sensor on the spindle to measure the coordinate position of the master ring, the coordinate position of the master ring measured by the tester, and the master ring measured by the touch sensor A third step of calculating a difference from the coordinate position of the first, a fourth step of setting the difference calculated in the third step as a correction value of a measurement value by the touch sensor, and the jig by the touch sensor. A fifth step of measuring the coordinate position of the second coordinate, and correcting the coordinate position measured in the fifth step based on the correction value. A sixth step of setting a coordinate position of the jig is made of.

  According to this configuration, it is possible to measure the coordinate position of the jig after calibrating the measurement error of the touch sensor whose reliability of detection accuracy is not sufficient due to the bending of the probe tip, and to accurately identify the coordinate position of the jig. can do. As a result, the processing accuracy of the workpiece can be improved.

  In one embodiment of the present invention, the fifth step measures the coordinate position according to the direction of the jig at the time of machining, and the sixth step measures the measurement according to the direction of the jig at the time of machining. Each coordinate position is corrected.

  According to this configuration, even if the direction is changed during the processing, correction according to the direction can be performed.

  In one embodiment of the present invention, the jig is a flat jig provided with a fixing pin for fixing a workpiece, and the fifth step measures the position of the fixing pin, With respect to the Z coordinate along the center line direction, the Z coordinate position on one side of the fixed pin is measured, and the coordinate position of the fixed pin is obtained from the measured Z coordinate of the pin and the radius of the fixed pin.

  According to this configuration, the Z coordinate of the jig can be easily determined by calculation.

  In one embodiment of the present invention, the jig is a flat jig provided with a fixing pin for fixing a workpiece, and the fifth step is to measure the position of the fixing pin, and the center of the spindle With respect to the X coordinate orthogonal to the line direction on the horizontal plane, the X coordinate on both sides of the fixed pin is measured, and the coordinate position of the fixed pin is obtained based on the average of the measured coordinate positions.

  According to this configuration, the X coordinate can be specified with high accuracy by calculation.

  In one embodiment of the present invention, the fifth step measures the coordinate position in a state where the measurement pin is inserted into the fixed pin.

  According to this configuration, even if the height position of the fixed pin is extremely low with respect to the main shaft, the measurement position can be set to a high position by the measurement pin. It is possible to prevent inadvertent contact with other fixing pins, side surfaces of jigs, and the like, and the coordinate position can be easily measured.

  The processing apparatus using the jig coordinate specifying method of the present invention is fixed to a jig by a main shaft configured to be able to hold a tester and a touch sensor, and operating the main shaft, and a tester held by the main shaft. First measurement operation means for measuring the coordinate position of the master ring and the second measurement operation for operating the main shaft and measuring the coordinate position of the master ring fixed to the jig by the touch sensor gripped by the main shaft. Means for calculating a difference between the coordinate position of the master ring measured by the tester and the coordinate position of the master ring measured by the touch sensor, and the difference calculated by the calculator And a correction value setting means for setting as a correction value of a measurement value by the touch sensor, and the spindle is operated, and the touch sensor Jig coordinate position measurement operating means for measuring the coordinate position of the tool, and correction coordinate position setting means for correcting the coordinate position measured by the touch sensor based on the correction value and setting it as the coordinate position of the jig; And machining control means for executing machining control of the workpiece based on the coordinate position of the jig corrected by the corrected coordinate position setting means.

  According to this configuration, it is possible to measure the coordinate position of the jig after calibrating the measurement error of the touch sensor whose reliability of detection accuracy is not sufficient due to the bending of the probe tip, and to accurately identify the coordinate position of the jig. can do. As a result, the processing accuracy of the workpiece can be improved.

  According to this invention, it is possible to measure the coordinate position of the jig after calibrating the measurement error of the touch sensor whose reliability of detection accuracy is not sufficient due to the bending of the probe tip, and to accurately identify the coordinate position of the jig. can do. As a result, the processing accuracy of the workpiece can be improved.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a machining center which is a processing apparatus according to the present invention. In the figure, a machining center denoted by reference numeral 10 has an XYZ coordinate system composed of X, Y, and Z axes as a machine coordinate system. The X-axis and Z-axis directions are horizontal directions, and the Y-axis direction is a vertical direction.

  The machining center 10 has a spindle 14 that rotates a machining tool 12 such as a drill, an end mill, and a milling cutter about a rotation center line Cs that extends in the Z-axis direction, and moves the spindle 14 in the Y direction and also in the X direction. The column 16, the processing table 20 for placing the jig 18, the rotation mechanism 22 for rotating the processing table 20 around the rotation center line Ct extending in the Y-axis direction, and the feed for moving the rotation mechanism 22 in the Z direction It has a mechanism 24.

  Further, the machining center 10 is a so-called numerically controlled processing apparatus, and corresponds to a workpiece stored in the storage unit 150 in the control unit 100 of the machining center 10 as shown in FIG. 2 showing a control system of the machining center. Thus, various machining is performed according to machining program data (NC program data) 160 created in advance. Details of the control system of the machining center 10 will be described later.

  Further, the machining center 10 includes an automatic tool changer (ATC) 26 as shown in FIG. The ATC 26 is for exchanging the machining tool 12 attached to the spindle 14, and according to the machining program data 160 (according to the tool number of the machining program 160), the machining tool 12 attached to the spindle 14, for example, a plurality of Each of the magazine pods is configured to exchange one of various processing tools waiting. As a result, the machining center 10 performs various processes using various process tools 12.

  3 and 4 show the jig 18 for positioning the workpiece W. FIG. The jig 18 is an scale jig in which an opening 32 is formed in a jig main body 31 standing upright on a base 30 fixed to the upper surface of the processing table 20. In addition to the base 30 and the jig body 31, the jig 18 includes a plurality of clamp devices (not shown) including clampers that clamp the workpiece W and hold the position thereof. The jig 18 has a master ring 40 in the jig body 31.

  Further, the jig 18 is fixed on the processing table 20 of the machining center 10 so that the master ring 40 of the jig body 31 faces the spindle 14 as shown in FIG. . Specifically, the master ring 40 has a cylindrical shape, and the jig 18 is fixed to the processing table 20 so that the center line Cm of the master ring 40 has a posture in which the Z direction is parallel. The master ring 40 will be described later.

  Next, with reference to FIG.3 and FIG.4, the process process of the surface A of the workpiece | work W and the surface B is demonstrated. As shown in FIGS. 3 and 4, the surface A and the surface B of the workpiece W are processed in a state where the workpiece W is held by the jig 18. Here, in FIG. 3, the surface A of the workpiece W is in a state of facing the machining tool 12, and the surface A is machined by the machining tool 12 sent in the X axis direction, the Y axis direction, and the Z axis direction by the machining center 10. .

  On the other hand, when the processing table 20 is rotated 180 ° from the state shown in FIG. 3 and the direction of the jig 18 and the workpiece W is changed, the surface B on the opposite side of the surface A of the workpiece W as shown in FIG. 12 is in a state of facing. Here, the surface B of the workpiece W is processed by the machining center 12 by the machining center 10 that is fed in the Z direction from the opening 32 side.

  FIG. 5 shows the second jig 50 for positioning the workpiece W. The jig 50 is a flat flat jig installed so that a fixed surface spreads along a horizontal plane. In addition to the base 51, the jig 50 includes a plurality of clamping devices (not shown) including clampers that clamp the workpiece W and hold the position thereof.

  Next, processing steps for the surface C, the surface D, the surface E, and the surface F other than the surfaces A and B of the workpiece W will be described. Surfaces C to F are planes orthogonal to the surfaces A and B. Therefore, when processing the surfaces C to F, the workpiece W is held by a jig 50 different from the jig 18 in a posture in which the surfaces C to F are orthogonal to the X axis and the Z axis. Here, in FIG. 5, the surface C of the workpiece W is in a state of facing the processing tool 12, and the surface C is processed by the processing tool 12 in this state.

  Further, from the state shown in FIG. 5, the direction of the jig 50 and the workpiece W is changed by rotating the machining table 20 by 90 °, and the surfaces D to F of the workpiece W are respectively opposed to the machining tool 12. By doing, the surface D-the surface F can be processed in order with the processing tool 12. FIG.

  Through the above processing steps, it is possible to process all the surfaces A to F of the workpiece W only by exchanging the jig once.

  By the way, as described above, when the workpiece W is fixed to the jigs 18 and 50 and the machining is performed, in order to machine the workpiece W held by the jigs 18 and 50 with high accuracy, It is necessary to detect the position coordinates and reference point coordinates of the holding jigs 18 and 50 in the XYZ coordinate system, and execute processing based on the detected coordinates.

Here, an example of the jig coordinate specifying method according to the present invention will be described with reference to the flowcharts of FIGS. 6 and 10 and the explanatory diagrams of FIGS. 5 to 9, 11 and 12.
First, the sensor calibration process shown in the flowchart of FIG. 6 is executed. In step s1 of FIG. 6, as shown in FIG. 7A, a contact-type small tester 60 that has relatively high detection accuracy and high reliability is inserted into the spindle 14 of the machining center 10 via a predetermined holder 70. The jig 18 to which the master ring 40 is fixed is fixed to the processing table 20.

  Here, the operator operates the column 16 and the feed mechanism 24 by appropriately operating the operation unit 41 (see FIG. 2) of the machining center 10.

  Here, the probe 61 provided at the tip of the small tester 60 is brought close to the master ring 40 while adjusting the feed amount of the column 16 and the feed mechanism 24 by manual operation via the operation unit 41. And after moving the probe 61 inside the master ring 40, it is made to contact the inner peripheral surface 40a of the hole. Specifically, the position of the spindle 14, that is, the probe 61 of the small tester 60 in the X direction and the Y direction is adjusted by the operation of the column 16, and the operation of the feed mechanism 24 in the Z direction of the probe 61 of the small tester 60. Adjust the position. The operation unit 41 includes a liquid crystal touch panel, a keyboard, and the like attached to the machine base of the machining center 10.

  Here, when the probe 61 of the small tester 60 comes into contact with the inner peripheral surface 40a of the master ring 40, the operator rotates the spindle 14 by operating the operation unit 41, and as shown in FIG. 61 is scanned on the inner peripheral surface 40 a of the master ring 40. Thereby, the coordinate detection unit 102 measures the X coordinate Xm0 and the Y coordinate Ym0 of the master ring 40 when the reference point of the machining center 10 is the origin Omc.

  When the X-coordinate Xm0 and Y-coordinate Ym0 of the master ring 40 are measured by the above-described method, the operator appropriately operates the operation unit 41 and controls this as the true coordinate position data of the master ring 40, that is, the absolute position data 152. The data is stored in the storage unit 150 (see FIG. 2) of the unit 100.

  Next, the operator removes the small tester 60 from the spindle 14 and fixes the Z-direction side fixing tool 80 shown in FIG. Then, the column 16 and the feed mechanism 24 are operated by the operation of the operation unit 41, and the probe 81 provided at the distal end portion of the Z-direction side fixture 80 is brought close to the master ring 40 as in the case of the small tester 60, and the center It is made to contact the end surface 40b orthogonal to the line Cm. The Z-direction side fixing tool 80 is a contact type like the small tester 60, and has relatively high detection accuracy and high reliability.

  Here, when the probe 81 comes into contact with the end surface 40b of the master ring 40, the Z-direction measuring tool 80 displays that fact on the display unit 82 by an appropriate numerical value (for example, “0.000” or the like). At this time, the coordinate surface projecting portion 102 measures the Z-direction dimension z2 from the tip of the spindle 14 to the end surface 40b of the master ring 40. Here, the dimension from the origin Omc to the end face 40b, that is, the Z coordinate Zm0 of the master ring 40, is obtained from the sum of the dimension z1 from the origin Omc to the tip of the spindle 14 and the above-mentioned z2, which is known in advance.

  When the Z coordinate position of the master ring 40 is measured by the above-described method, the operator appropriately operates the operation unit 41 and stores the Z coordinate position in the storage unit 150 of the control unit 100 as the absolute position data 152.

  As described above, the step s1 of measuring the absolute position of the master ring 40 (meaning the true position coordinate with respect to the origin Omc of the master ring 40) is performed by the above-described measurements using the small tester 60 and the Z direction measuring tool 80. Is done.

  Next, the process proceeds to step s2, and the coordinate position of the master ring 40 is measured using the touch sensor 90 shown in FIG. The touch sensor 90 is housed in the magazine pod of the ATC 26 except during coordinate measurement, and is exchanged with the processing tool 12 held by the spindle 14 by the ATC 26 during coordinate measurement.

  The touch sensor 90 is moved in the X direction by the column 16 while being held by the spindle 14, and automatically measures the X coordinate of the contact point when the workpiece W or the jig 18 contacts the tip. Further, when it is moved in the Y direction and comes into contact with the workpiece W or the jig 18, the X coordinate of the contact point is automatically measured.

  Further, when the feed mechanism 24 feeds the workpiece W or the jig 18 in the Z direction and the tip of the touch sensor 90 comes into contact with the workpiece W or the jig 18, the Z coordinate of the contact point is automatically measured. It is configured. A signal for the coordinates measured by the touch sensor 90 is transmitted to the coordinate detection unit 102 of the control unit 100 of the machining center 10. The coordinate measurement is performed by automatically operating the touch sensor 90 by the coordinate detection unit 102, as shown in FIG.

  The coordinate detection unit 102 operates the column 16 and the feed mechanism 24 to bring the long probe 91 provided at the tip of the touch sensor 90 closer to the master ring 40. And after moving the probe 91 inside the master ring 40, it is made to contact the inner peripheral surface 40a of the hole.

  Here, when the probe 91 of the touch sensor 90 comes into contact with the inner peripheral surface 40 a of the master ring 40, the coordinate detection unit 102 rotates the spindle 14 to drive the probe 91 to the master ring 40 as in the case of the small tester 60. The X coordinate Xm1 and Y coordinate Ym1 of the master ring 40 are measured by scanning on the inner peripheral surface 40a.

  When the coordinate detection unit 102 measures the X-coordinate Xm1 and the Y-coordinate Ym1 of the master ring by the method described above, the coordinate detection unit 102 stores them in the storage unit 150 of the control unit 100 as sensor detection position data 154 (see FIG. 2).

  Next, the coordinate detection unit 102 contacts the probe 91 of the touch sensor 90 with the end surface 40b of the master ring 40, and measures the Z coordinate Zm1 of the master ring 40.

  When the coordinate detection unit 102 measures the Z coordinate Zm1 of the master ring, the coordinate detection unit 102 stores it in the storage unit 150 of the control unit 100 as sensor detection position data 154.

  Here, when the probe 91 of the touch sensor 90 is bent, as shown in FIG. 9, the position of the tip portion is shifted, and therefore the detection result is shifted from the absolute position described above. There is.

  Therefore, in step s3, the sensor calibration calculation unit 104 (see FIG. 2) constituting the control unit 100 performs the comparison calculation between the absolute position data 152 and the sensor detection position data 154, and the coordinate position (Xm0) measured in step s1. , Ym0, Zm0) and the difference (Xm1-Xm0, Ym1-Ym0, Zm1-Zm0) between the coordinate positions (Xm1, Ym1, Zm1) measured in step s2, and the width of the detection error of the touch sensor 90 Is calculated.

  Then, the process proceeds to step s4, and the sensor calibration calculation unit 104 calculates the difference between the data 152 and 154 calculated in step s3 in the n (n is X, Y, Z) coordinates measured by the touch sensor 90. The correction value Δn is set and stored in the storage unit 150 of the control unit 100 as correction value data 156 (see FIG. 2).

  As described above, the sensor calibration process for calibrating the detection error of the touch sensor 90 caused by the bending of the probe 91 is executed by the above-described steps s1 to s4.

  Next, the jig coordinate position data correction step shown in the flowchart of FIG. 10 is executed. In step s11 shown in FIG. 10, the coordinate position of the jigs 18 and 50 is automatically measured by bringing the touch sensor 90 into contact with the jigs 18 and 50 by automatic operation of the coordinate detection unit 102. 1, 3, and 4, the illustration is omitted for the sake of convenience, but as shown in FIG. 11, the jig 18 is inserted into a reference hole (not shown) formed in the workpiece W to be X-axis. A plurality of processing reference seats 33 for fixing the workpiece W with respect to the direction and the Y-axis direction are provided on one side of the jig body 31. The reference hole of the workpiece W is a hole that serves as a reference for the positions of a plurality of parts to be processed of the workpiece W, and is also a hole that determines the position of the workpiece W in the XYZ coordinate system of the machining center 10.

  In step s11, as shown in FIG. 11, the jig 18 moves each direction in the direction when machining the surface A of the workpiece W (see FIG. 3) and the direction when machining the surface B (see FIG. 4). The coordinate position is measured according to.

  In FIG. 11A, the surface A of the workpiece W is fixed in the direction of machining, the probe 91 of the touch sensor 90 is brought into contact with the machining reference seat 33, and the Z coordinate Zj1a detected at that time is measured. .

  In FIG. 11B, the jig 18 is fixed in the direction in which the surface B of the workpiece W is machined by rotating the machining table 20 180 degrees from the state shown in FIG. At this time, the probe 91 of the touch sensor 90 is brought into contact with the back surface of the jig body 31, and the Z coordinate z4 is measured. Here, the Z coordinate Zj1b of the machining reference seat 33 is the above-described coordinate measured by the touch sensor 90 to the dimension z3 obtained by combining the thickness of the jig main body 31 and the protrusion amount of the machining reference seat 33, which are known in advance by actual measurement. The sum z3 + z4 can be obtained by adding z4.

  By the way, although the jig 50 is not shown for convenience in FIG. 4, as shown in FIG. 12A, the jig 50 is inserted into the reference hole of the workpiece W and is related to the X-axis direction and the Z-axis direction. A plurality of processing reference seats 52 for fixing the workpiece W are provided on the base 51. Here, when measuring the coordinate position of the jig 50, a measurement pin 53 is inserted into one of the machining reference seats 52 as shown in the figure. When the measurement pin 53 is inserted into the machining reference seat 52, as shown in the drawing, the measurement pin 53 is arranged on the same axis as the drawing and protrudes upward from the others.

  In step s11, as shown in FIG. 12A, the probe 91 of the touch sensor 90 is brought into contact with the upper end surface of the processing reference seat 52 where the measurement pin 53 is not inserted, and the Y coordinate Yj2 detected at that time is used. measure.

  Next, the probe 91 of the touch sensor 90 is brought into contact with the measurement pin 53, and the X coordinates Xj2 and Zj2 are measured.

  When measuring the X coordinate Xj2, as shown in FIG. 12 (b), the tip of the probe 91 is brought into contact with both ends in the X direction of the side surface of the measurement pin 53, and the X of the two contacts P1 and P2 is measured. The coordinates x1 and x2 are measured. Here, the X coordinate Xj2 of the measurement pin 53 is a coordinate of the center point of the measurement pin 53, and is an intermediate coordinate between the X coordinates x1 and x2 of the two contact points. Therefore, the X coordinate Xj2 can be obtained from the average value (x1 + x2) / 2 of the coordinates of the two contact points P1 and P2.

When the Z coordinate Zj2 is measured, as shown in FIG. 12C, the tip of the probe 91 is brought into contact with the spindle 14 side end of the side surface of the measurement pin 53, and the Z coordinate of the contact point P3 is measured. z6 is measured. Here, the Z coordinate Zj2 of the measurement pin 53 is
Since it is the coordinate of the center point of the measurement pin 53, the Z coordinate Zj2 can be obtained by a value z5 + z6 obtained by adding the radius z5 to the coordinate z6 of the contact P3.

  In this way, in step s11 shown in FIG. 10, by specifying the coordinate positions of the jigs 18 and 50 (the machining reference seats 33 and 52), the jigs are processed at all machining angles (the machining target surfaces A to F). The coordinate position of is measured. Here, the measurement result measured by the method described above is stored as jig coordinate position measurement data 158 in the storage unit 150 of the control unit 100.

  Next, the process proceeds to step s12. Here, the machining data correction unit 106 (see FIG. 2) constituting the control unit 100 adds the correction value Δn in the correction value data 156 to each coordinate measurement value in the coordinate position measurement data 158, and the touch sensor 90. The coordinate positions of the measured jigs 18 and 50 are corrected, and the machining program data 160 stored in the storage unit 150 is corrected.

  As described above, the jig coordinate position data correction step of correcting the detection error due to the bending of the probe 91 of the touch sensor 90 with respect to the measurement value of the coordinate position of the jigs 18 and 50 by the above-described steps s11 and s12. Is executed.

  The machining program data 160 is so-called NC program data, and includes coordinate values based on the XYZ coordinate system, and performs machining based on the coordinate values. For example, the machining center 10 is caused to perform chamfering for sending a milling machine from the coordinates F1 to the coordinates F2 of the XYZ coordinate system. Further, in the machining program data 160, the jig reference point (machining reference seats 33 and 52) is at a predetermined jig arrangement position in the XYZ coordinate system, and the workpiece reference point has the jig reference point as the origin. The jigs 18 and 50 are created based on coordinate values based on a theoretical XYZ coordinate system in a predetermined position in the coordinate system of the jigs 18 and 50.

  In the case of the jig 18, since the measured coordinates are Zja1 and Zja2, the corrected coordinates are expressed as Zj1a + ΔZ and Zj1b + ΔZ, respectively. In the case of the jig 50, the measured coordinates are (Xj2, Yj2, Zj2), and thus the corrected coordinates are represented by (Xj2 + ΔX, Yj2 + ΔY, Zj2 + ΔZ), respectively.

  Further, the machining data correction unit 106 calculates the deviation amount of the jig reference point in the XYZ coordinate system. The amount of deviation is the coordinates of the corrected processing reference seats 33 and 52 (actual coordinates) and the coordinates of reference points on the jigs 18 and 50 in the XYZ coordinate system determined from the drawing (predetermined jig arrangement). It is the difference from the position coordinates (theoretical coordinates).

  The machining data correction unit 106 corrects the coordinate value in the machining program data 160 based on the deviation amount of the jig reference point. Therefore, in the present embodiment, the measurement result measured by the touch sensor 90 is corrected in consideration of the detection error of the touch sensor 90 and the correction in consideration of the deviation amount of the jigs 18 and 50.

  The control unit 100 executes machining control of the workpiece W according to the machining program data 160 corrected by the above-described method. Thereby, the coordinate position data in consideration of the detection error of the touch sensor 90 and the shift amount of the jigs 18 and 50 can be specified, and the machining accuracy of the machining center 10 can be improved.

  As described above, in this embodiment, the coordinate position of the master ring 40 is measured using the small tester 60, the Z direction measuring tool 80, and the touch sensor 90 with relatively high measurement accuracy. The correction value Δn is calculated based on the correction value Δn, and the coordinate positions of the jigs 18 and 50 measured by the touch sensor 90 are corrected based on the correction value Δn. For this reason, the coordinate position of the jigs 18 and 50 can be measured after correcting the measurement error of the touch sensor 90 whose reliability of detection accuracy is not sufficient due to the bending of the tip of the probe 91, and the coordinates of the jigs 18 and 50 are measured. The position can be specified with high accuracy. As a result, the processing accuracy of the workpiece W can be improved.

  In step s11, the coordinate positions Zj1a and Zj1b are measured according to the direction of the jig 18 at the time of machining, respectively, and in step s12, the coordinate positions are corrected according to the respective directions. Thereby, even if it changes a direction in the middle of a process like the jig | tool 18, the correction | amendment according to the direction can be performed.

  Further, in the jig 50, the coordinate position of the machining reference seat 52 (measurement pin 53) is measured, and the Z coordinate Zj2 is determined from the coordinate z6 of the contact P3 on one side of the measurement pin 53 and the measurement pin. By determining based on the radius z5 of 53, the Z coordinate Zj2 of the jig 50 can be easily specified by calculation.

  Further, when measuring the X coordinate of the coordinate position of the machining reference seat 52 (measurement pin 53), as described above, the X coordinate Xj2 is based on the average value of the coordinate positions of both ends in the X direction of the measurement pin 53. Thus, the X coordinate Xj2 can be specified with high accuracy by calculation.

  Further, when measuring the X coordinate Zj2 and the Z coordinate Zj2 in the jig 50, the measurement is performed with the measurement pin 53 inserted in the machining reference seat 52, as shown in FIG. Even if the height position of the machining reference seat 52 is extremely low with respect to the spindle 14 of the machining center 10, the measurement position can be set to a high position by the measurement pin 53. For this reason, when the touch sensor 90 is moved downward, it is possible to prevent inadvertent contact with the other processing reference seat 52 or the side surface of the base 51 of the jig 50, and the coordinate position can be easily measured.

  The present invention is applied to, for example, processing of vehicle parts such as a transmission case and an engine cylinder block. However, the present invention is not necessarily limited to this, and can be applied to workpieces in other industrial fields.

  In the touch sensor calibration process shown in the flowchart of FIG. 6, the case where the master ring 40 is attached to the scale jig 18 has been described. However, the present invention is not limited thereto, and the master ring 40 may be attached to the side surface of the flat jig 50.

In correspondence between the configuration of the present invention and the above-described embodiment,
The main shaft of the present invention corresponds to the spindle 14,
Similarly,
The fixing pin corresponds to the processing reference seats 33 and 52,
The first measurement operation unit corresponds to the operation unit 41 and the coordinate detection unit 102 that executes step s1,
The second measurement actuating means corresponds to the coordinate detection unit 102 that executes step s2,
The calculation means corresponds to the sensor calibration calculation unit 104 that executes Step s3,
The correction value setting means corresponds to the sensor calibration calculation unit 104 that executes step s4.
The jig coordinate position measurement operating means corresponds to the coordinate detection unit 102 that executes step s11,
The correction coordinate position setting means corresponds to the machining data correction unit 106 that executes step s12,
The processing control means corresponds to the control unit 100,
The present invention is not limited only to the configuration of the above-described embodiment, and many embodiments can be obtained.

The perspective view which shows the machining center which is a component of the workpiece processing apparatus which concerns on embodiment of this invention. The block diagram which shows the control system of the machining center shown in FIG. The perspective view which shows the workpiece | work currently hold | maintained at the scale jig | tool. The perspective view which shows the workpiece | work currently hold | maintained at the scale jig | tool. The perspective view which shows the workpiece | work currently hold | maintained at the flat jig. The flowchart which shows a touch sensor calibration process. Explanatory drawing for demonstrating the method to measure the coordinate position of a master ring using a small tester. Explanatory drawing for demonstrating the method to measure the coordinate position of a master ring using a Z direction measuring tool. Explanatory drawing for demonstrating the method to measure the coordinate position of a master ring using a touch sensor. The flowchart which shows a jig | tool coordinate position data correction process. Explanatory drawing for demonstrating the method to measure the coordinate position of an scale jig | tool using a touch sensor. Explanatory drawing for demonstrating the method to measure the coordinate position of a flat jig using a touch sensor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Machining center 14 ... Spindle 33, 52 ... Processing reference seat 40 ... Master ring 53 ... Measuring pin 60 ... Small tester 80 ... Z direction measuring tool 90 ... Touch sensor 100 ... Control part 102 ... Coordinate detection part 104 ... Sensor calibration calculation Unit 106: Machining data correction unit

Claims (6)

A first step of measuring a coordinate position of the master ring by fixing a master ring to a jig of a processing apparatus and holding a tester on a spindle;
A second step of fixing a master ring to a jig of the processing apparatus, and gripping a touch sensor on the spindle to measure a coordinate position of the master ring;
A third step of calculating a difference between the coordinate position of the master ring measured by the tester and the coordinate position of the master ring measured by the touch sensor;
A fourth step of setting the difference calculated in the third step as a correction value of the measurement value by the touch sensor;
A fifth step of measuring the coordinate position of the jig by the touch sensor;
And a sixth step of correcting the coordinate position measured in the fifth step based on the correction value and setting it as the coordinate position of the jig. In the fifth step, each coordinate position is measured according to the direction of the jig during processing,
The jig coordinate specifying method for a machining apparatus according to claim 1, wherein the sixth step corrects each of the measured coordinate positions according to the direction of the jig during machining. The jig is a flat jig provided with a fixing pin for fixing a workpiece,
In the fifth step, the position of the fixed pin is measured, and with respect to the Z coordinate along the center line direction of the spindle, the Z coordinate on one side of the fixed pin is measured,
2. The jig coordinate specifying method for a machining apparatus according to claim 1, wherein the coordinate position of the fixed pin is obtained from the measured Z coordinate of the pin and the radius of the fixed pin. The jig is a flat jig provided with a fixing pin for fixing a workpiece,
In the fifth step, the position of the fixed pin is measured, and with respect to the X coordinate orthogonal to the center line direction of the main axis on the horizontal plane, the X coordinate on both sides of the fixed pin is measured.
4. The jig coordinate specifying method for a processing apparatus according to claim 3, wherein the coordinate position of the fixed pin is obtained based on an average of the measured coordinate positions. The fifth step is a jig coordinate specifying method for a processing apparatus for measuring a coordinate position in a state where a measurement pin is inserted into the fixed pin. A processing apparatus using the jig coordinate specifying method according to any one of claims 1 to 5,
A spindle configured to be able to grip a tester and a touch sensor;
A first measurement actuating means for actuating the spindle and measuring a coordinate position of a master ring fixed to the jig by a tester held by the spindle;
A second measurement actuating means for actuating the spindle and measuring a coordinate position of a master ring fixed to the jig by a touch sensor held by the spindle;
Calculating means for calculating a difference between the coordinate position of the master ring measured by the tester and the coordinate position of the master ring measured by the touch sensor;
Correction value setting means for setting the difference calculated by the calculation means as a correction value of a measurement value by the touch sensor;
A jig coordinate position measuring operation means for operating the spindle and measuring the coordinate position of the jig by the touch sensor;
Correction coordinate position setting means for correcting the coordinate position measured by the touch sensor based on the correction value and setting it as the coordinate position of the jig;
A machining apparatus using a jig coordinate specifying method, comprising machining control means for executing machining control of a workpiece based on the coordinate position of the jig corrected by the corrected coordinate position setting means.

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