JP2010261774A - Detector for measuring object position, and cutting machine having the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a detector for a measuring object position for accurately detecting the position displaced due to the thermal displacement of a measuring object as a rotor with a simple configuration, and to provide a cutting machine having the detector of the measuring object position. <P>SOLUTION: A position-detecting means 18 faces a flange 66, connected to a chuck 12, and detects the position displaced by thermal displacement of the chuck 12. In other words, the position of the chuck 12 can be detected accurately by using a simple constitution. Since the position detector 18 accurately detects the position, corresponding to the thermal displacement of the chuck, accurate movement of a cutting tool 25 or 26 to a cutting position can be made. Furthermore, position data, or the like, of the chuck 12 can be output via the position detecting means 18, as a member different from the rotating chuck 12 so that a need for a brush holder, or the like, can be eliminated. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an object position detecting device used for a cutting machine such as an NC lathe, and more particularly to an object position detecting device for detecting a position displaced by a thermal displacement of a chuck or the like serving as an object to be measured and the object to be detected. The present invention relates to a cutting machine including a measurement object position detection device.

  For example, Patent Document 1 discloses a cutting edge position measuring device that does not cause measurement errors due to machining heat or environmental temperature changes, and that can also measure the cutting edge shape, the amount of wear, the dimensions of a workpiece, and the like. Has been. Specifically, a measurement reference surface positioned with respect to a machining reference point serving as a reference for numerical control is formed on the reference piece, and the contour of the measurement reference surface and the cutting edge of the tool is captured by the camera. The captured contour is stored in the image memory as electrical image information, and the relative position calculation circuit calculates the relative distance between the machining reference point and the cutting edge based on the image information. That is, in Patent Document 1, the relative position can be measured without being affected by the displacement of the part due to heat or the like.

  And in one Example of patent document 1, the numerical control apparatus is provided with the blade edge | tip position measuring apparatus which measures those relative distance between a process reference point and the blade edge of a tool. This cutting edge position measuring device includes a reference piece having a measurement reference plane whose relative position with respect to the machining reference point is determined in advance, a camera that captures the measurement reference plane and the outline of the cutting edge as an image, and a main processor. The reference piece is held by the chuck of the main shaft (see paragraph number “0015” and FIG. 1).

Japanese Patent Laid-Open No. 9-253979

  By the way, in Patent Document 1, a reference piece (synonymous with a test piece) is mounted in a state where the machining operation of the machine tool is temporarily stopped, and an operation resumption process (such as removal of the reference piece) after measurement is required. Therefore, time and labor for that are required. That is, for the measurement process, the machining operation of the machine tool is stopped and restarted, and the attachment and detachment of the reference piece with respect to the chuck becomes troublesome and the usability is poor.

  Further, the reference for measuring the moving amount of the cutting edge of the cutting tool, that is, the NC table (that is, vector measurement of the cutting tool) varies. That is, for example, the chuck serving as the reference is thermally displaced by the environmental temperature or the like, but the prior art including Patent Document 1 has no solution for thermal displacement.

  Further, in Patent Document 1, for example, when a cutting tool such as a cutting tool and a peripheral surface of a chuck are stored in an imaging region of a camera (hereinafter also referred to as a single view), generally, dirt or rust on the outer peripheral surface of the chuck, etc. Depending on the state, it is difficult to accurately measure the relative position of the cutting tool and the chuck. That is, when the image is taken by the camera, it is necessary to take an image in a light-projected state because the periphery of the chuck is dark. There is a case. Note that if the chuck or the like is specially processed, high-accuracy imaging can be performed, but it is expensive.

  An object of the present invention is to provide a measurement object position detection device that can accurately detect a position displaced by a thermal displacement of a measurement object that is a rotating body, and a cutting machine including the measurement object position detection device. It is to provide.

  An object position detecting device according to the present invention includes a detecting means for detecting a position displaced by a thermal displacement of an object to be rotatably arranged, and the detecting means is the above-mentioned at least one of when stationary and when rotating. It is characterized in that the position is detected facing the object to be measured. In the measurement object position detection apparatus, an auxiliary body made of the same material as the metal constituting the measurement object is arranged in connection with the measurement object, and the detection means heats the auxiliary body. The position displaced by the displacement may be detected.

  In each of the measured object position detecting devices, the detecting means may be moved relative to the measured object. In the device position detecting apparatus according to the present invention, the detecting means is at least one of an X direction sensor that detects a position in the X direction of the device to be measured and a Z direction sensor that detects a position in the Z direction. A sensor may be arranged on the reference means. Furthermore, a temperature sensor that detects the temperature of the measurement object may be provided in the measurement object position detection device.

  A workpiece position detection device according to the present invention and a cutting machine equipped with the device position detection device calculate a cutting position of a cutting tool based on detection data by each of the measurement object position detection devices described above. And A measuring object position detecting device according to the present invention and a cutting machine provided with the measuring object position detecting device are each of the above-described measured object position detecting devices, an imaging means for imaging a subject, and A reference unit for measuring a position error of the imaging unit in the reference unit, and the imaging unit images the reference unit and the cutting tool in the same imaging region as a subject, and a cutting tool based on the captured image data The cutting position is calculated.

  Furthermore, a workpiece position detection device according to the present invention and a cutting machine equipped with the device position detection device separate the optical path corresponding to each subject at a different imaging position from each of the device position detection devices described above. Optical path separating means and an image sensor disposed on the same optical path in the optical path separating means, and the optical path separating means determines the optical path at the other imaging position when imaging the subject at one imaging position. An imaging device to be shut off, and a reference unit for measuring a position error of the imaging unit in the reference unit according to claim 4, wherein the imaging device includes the reference unit at one imaging position in the one optical path and the reference unit. The cutting tool at one imaging position is imaged as a subject in the same imaging area, or the reference portion at the one imaging position in the one optical path is imaged as a subject. The cutting tool of the other imaging position in the serial other optical path is imaged with a time difference of optical path switching, and calculates a cutting position of the cutting tool on the basis of the image data the imaging.

  In the measurement object position detection apparatus according to the present invention, the detection means faces the measurement object in at least one of the stationary state and the rotation state, and detects the position displaced by the thermal displacement of the measurement object. That is, according to the measured object position detecting device according to the present invention, since the detection means is configured to face the measured object that is rotatably arranged, the position displaced by the thermal displacement of the measured object can be easily and accurately determined. It can be detected. According to the cutting machine provided with the device position detection device according to the present invention, the detection means is opposed to the device to be measured in at least one of the stationary state and the rotation state, and detects the position displaced by the thermal displacement of the device to be measured. Therefore, the cutting tool can be accurately moved to the cutting position based on the detection (position) data.

  Moreover, according to the cutting machine provided with the object position detection device according to the present invention, the relative of the cutting tool is determined based on the detection data of the detection device without using a test material (including a test piece as in the conventional example). The vector (position of the entire cutting tool) can be detected accurately. Furthermore, according to the cutting machine provided with the object position detection device according to the present invention, the position data of the object to be measured can be output via the detection device that is a separate member from the rotating object to be measured. Therefore, for example, a brush holder or the like can be eliminated.

It is a front view which shows the single axis | shaft type turret lathe of Example 1 which concerns on this invention. It is a side view which shows the principal part of the turret lathe shown in FIG. 3A and 3B are diagrams related to the imaging device shown in FIG. 2, in which FIG. 3A is an end view of the imaging device, and FIG. 3B is a plan view of the shutter. FIG. 4 is an end view showing a state in which the imaging device shown in FIG. It is a figure which detects the position of a chuck | zipper with the position detection apparatus which concerns on Example 1. FIG. FIG. 6 is a procedure explanatory diagram for obtaining initial data (vector data) of an image capture position relating to the byte shown in FIG. 5. It is a figure which detects the position of a chuck | zipper with the position detection apparatus which concerns on Example 2. FIG. It is a figure which shows the principal part of the position detection apparatus of Example 2. FIG. It is a figure which shows the position detection apparatus which concerns on another modification. It is a figure which shows a blade-tip cleaning apparatus. It is a side view of the blade edge | tip cleaning apparatus shown in FIG. 10, (A)-(E) is a figure which shows the cleaning state. It is a side view of the blade edge | tip cleaning apparatus shown in FIG. 10, (A)-(E) is a figure which shows the cleaning state. It is a figure which shows the blade-tip cleaning apparatus which concerns on another modification. It is a side view of the blade edge | tip cleaning apparatus which concerns on another modification, (A)-(E) is a figure which shows the cleaning state. It is a block diagram of the turret lathe shown in FIG. It is a flowchart figure regarding the byte image processing mode which concerns on the turret lathe shown in FIG. It is a figure which shows the test | inspection mode of a cutting tool. It is a figure which shows the test | inspection mode of a cutting tool. It is a figure which shows the test | inspection mode of a cutting tool. It is a figure which shows the test | inspection mode of a cutting tool. It is a figure which shows the test | inspection mode of a cutting tool. It is a figure which shows the test | inspection mode of a cutting tool. It is a figure which shows the test | inspection mode of a cutting tool. It is a figure which shows the test | inspection mode of a cutting tool. It is a figure which shows the test | inspection mode of a cutting tool. It is a figure which shows the test | inspection mode of a cutting tool. It is a figure which shows the test | inspection mode of a cutting tool. It is a figure which shows the test | inspection mode of a cutting tool. It is a figure which shows the test | inspection mode of a cutting tool. It is a figure which shows the test | inspection mode of a cutting tool. It is a figure which shows the mode of an inspection of a cutting tool, (A) is a figure which shows a mode that the edge of the chip | tip is calculated | required, (B)-(D) is a figure which shows a mode that the nose of a chip | tip is calculated | required.

  Hereinafter, specific Embodiment 1 and Embodiment 2 will be described with respect to modes for carrying out the present invention.

  Hereinafter, based on FIG. 1 thru | or FIG. 6, the to-be-measured object position detection apparatus which is Example 1 of this invention and a cutting machine provided with the to-be-measured object position detection apparatus are demonstrated. The cutting machine according to the first embodiment will be described as a single-axis type turret lathe (hereinafter simply referred to as a lathe) S.

(Schematic configuration of lathe S)
As shown in FIG. 1, in the lathe S, a headstock 10 fixed so that its axis line is parallel to the Z-axis direction (horizontal direction), a direction parallel to the Z-axis direction, and a direction orthogonal to the Z-axis direction. A turret device 20 that is movable in a direction parallel to the X-axis direction inclined backward by 60 degrees with respect to the vertical direction is arranged so as to face. A spindle 11 is supported on the spindle stock 10 so as to be rotatable about an axis parallel to the Z-axis direction. The main shaft 11 is rotationally driven by a main shaft drive motor (not shown). A chuck 12 that holds a workpiece W, which is a workpiece, is attached to the tip of the spindle 11 on the turret device 20 side. The headstock 10 and the spindle drive motor having such a configuration are disposed on the bed 13.

  The turret device 20 is provided with a turret tool post (hereinafter simply referred to as a tool post) 21 that is a mounting base so as to be able to rotate and index around an axis parallel to the Z-axis direction. On the tool post 21, a plurality of cutting tools 25, 26 (see FIG. 5) are attached at equal angular intervals on the circumference. The turret device 20 having such a configuration is arranged to be slidable in the X-axis direction and the Z-axis direction. The turret device 20 is moved by a NC motor 52 (see FIG. 15) of the NC table 50 via a ball screw mechanism (not shown). That is, the turret device 20 moves with respect to the headstock 10 that is fixedly arranged. On the other hand, the tool post 21 is rotationally driven by a turret motor (not shown).

  As shown in FIG. 1, a cover 14 that covers the headstock 10 and the turret device 20 is provided in the lathe S, and a partition wall 15 that partitions the headstock 10 side and the turret device 20 side is provided in the cover 14. ing. The partition wall 15 is mainly made of cutting powder or cutting fluid that scatters when the outer periphery or end surface of the workpiece W held by the chuck 12 by the cutting tools 25 and 26 shown in FIG. It is provided so as not to adhere to the table 10 or the like. That is, the headstock 10 side partitioned by the partition wall 15 is an isolation zone S1, and the turret device 20 side is a processing zone S2.

  The main shaft 11 protrudes from the hole provided in the partition wall 15 toward the machining zone S <b> 2, and a chuck 12 is attached to the tip of the main shaft 11. A measurement object position detection device (hereinafter also referred to as a position detection device) 18 shown in FIG. 5 is arranged so as to face the chuck 12 and measures the position error of the imaging device 27 shown in FIGS. 1 and 2. is there. This position detection device 18 is used in common for both the inner diameter machining tool 25 and the outer diameter machining tool 26.

(Configuration related to imaging device 27)
As shown in FIGS. 1 and 2, an imaging device 27 is slidably disposed in the lathe S between the isolation zone S1 and the processing zone S2 (see FIG. 4). The imaging device 27 images, for example, the chips 25A and 26A shown in FIG. 5 (the cutting edge when the cutting tool is not a chip such as a cutting tool) of the cutting tools (hereinafter also referred to as cutting tools) 25 and 26 as subjects. That is, the imaging device 27 slides toward the processing zone S2 when imaging the chips 25A, 26A, and the like, and slides toward the isolation zone S1 when imaging is completed. The image data picked up by the image pickup device 27 is configured to be output to a CPU 60 (see FIG. 15) which is a central processing unit. Then, the CPU 60 collates and calculates the displacements of the chips 25A and 26A and corrects the machining position of the cutting tool based on the results.

As shown in FIG. 3A, the housing 27A of the imaging device 27 is partitioned into an imaging space (also referred to as a lens chamber) 28A and a dust-proof space (also referred to as a shutter chamber) 28B. Specifically, the lens chamber 28A of the rectangular tubular casing 27A includes, for example, a 5 million pixel camera (including a CCD 30A as an image sensor) 30, an imaging lens body 29, a full mirror 31A, and a half mirror 31B. And are stored.
The half mirror 31B is disposed between the imaging lens body 29 and the full mirror 31A, and is a mirror that partially reflects and drops a part of incident subject light. The half mirror 31B (also referred to as a beam splitter) includes a flat plate type, a prism type, a wedge substrate type, or the like.

  The full mirror 31A and the half mirror 31B described above are arranged so that the fields of view of the respective imaging optical systems have the same size. That is, the full mirror 31A and the half mirror 31B are provided so that each subject can be alternately imaged. For example, when the subject (chip) 23A indicated by the two-dot chain line in FIG. 3A is imaged with the full mirror 31A, the optical path of the half mirror 31B is blocked, and when the subject (chip) 24A is imaged with the half mirror 31B. The optical path of the full mirror 31A is configured to be blocked.

  Accordingly, the optical path between the imaging lens body 29 of the camera 30 and two subjects (for example, bytes 23, 24, etc.) is bent at a right angle by the pair of mirrors 31A and 31B, respectively, so that one visual field region (synonymous with imaging region). The subject is imaged within the range of. Then, as shown in FIG. 3, for example, the chip 23A of the bite 23 is first imaged in one visual field area, and the chip 24A of the bite 24 is continuously imaged in one visual field area after the above imaging.

  The light source 43 or 44 shown in FIG. 1 emits light (that is, backlight illumination) from the opposite side of the imaging device 27, and imaging is performed on the rake face (that is, the surface outlined by the cutting line) side of the cutting tool 23 or 24. To do. Then, the CPU 60 processes the image and records it as monochrome (or color photograph) data of a silhouette. In this case, front light image processing may be performed. The field of view has a short side of 17 mm (2000 pixels) and a long side of 21.5 mm (2500 pixels) when a 5 million pixel camera is used.

  Between the lens chamber 28A and the shutter chamber 28B, the focusing lens 33 is disposed on the optical path corresponding to the full mirror 31A, and the transparent protective glass 34 is disposed on the optical path corresponding to the half mirror 31B. Here, the focusing lens 33 adjusts two series of focal lengths LA (for example, 100 mm). The lens chamber 28A is always maintained at a predetermined atmospheric pressure, for example, +0.15 MPa.

  A hole 27B is formed between the lens chamber 28A and the shutter chamber 28B, and compressed air (hereinafter also referred to as air) is sent from the hole 27B to the shutter chamber 28B. That is, the shutter chamber 28B is always pressurized to a pressure state lower than that of the lens chamber 28A, for example, +0.11 MPa. Therefore, since the shutter chamber 28B is pressurized, it prevents the coolant liquid or chips from flowing into the shutter chamber 28B. In addition, an air connection port (not shown) is arranged in the lens chamber 28A, and an air passage for supplying air generated by the compressor is provided between the air connection port and the compressor (not shown). Then, air is continuously blown out to the lens chamber 28A from before the shutter 38 or 39, which will be described later, is opened until the closing is completed.

  Openings 27C and 27D are formed in portions of the shutter chamber 28B facing the focusing lens 33 and the protective glass 34, respectively. Shutters 38 and 39 as switching means are slidably disposed between the casing 27A and the support piece 27E, and open or close the opening 27C or 27D. That is, the shutter 38 or 39 that blocks the optical path described above is configured to slide using the air in the air passage described above. Further, openings 27F and 27G are formed in the support piece 27E so as to face the openings 27C and 27D.

  As shown in FIG. 3B, the planar shape of the shutter 38 is a strip shape, and the planar shape of the shutter 39 is a substantially L-shape. The shutters 38 and 39 move so as to face the openings 27G and 27F, and open and close the openings 27C and 27D.

  That is, the shutters 38 and 39 open the respective optical paths, and the camera 30 captures an image of the tip 24A (indicated by a two-dot chain line in the drawing) of the cutting tool 24 that is the subject shown in FIG. The shutters 38 and 39 are closed to prevent coolant liquid or chips from flowing into the shutter chamber 28B. The shutters 38 and 39 are always closed and do not open the optical path at the same time. As the shutter, for example, a liquid crystal shutter that opens and closes by switching on / off of a voltage or an optical path switching mechanism may be applied.

  As shown in FIGS. 1 and 2, illumination light sources 43 and 44 are arranged at positions on the optical path opposite to the mirrors 31 </ b> A and 31 </ b> B (see FIG. 3) of the imaging device 27, respectively. These light sources 43 and 44 are comprised by light emitting LED etc., for example.

(Schematic configuration regarding the slide mechanism of the imaging device 27)
As shown in FIGS. 1 and 4, the imaging device 27 is disposed at a predetermined location of the partition wall 15 and is connected to a slide mechanism (not shown) (for example, a cylinder that is operated by air in an air passage). Therefore, as described above, the imaging device 27 slides between the isolation zone S1 and the processing zone S2, and retracts from the processing zone S2 to the isolation zone S1 immediately before the cutting process. The reason for retracting the imaging device 27 is to prevent interference with a cutting tool or the like mounted on the cutting turret device 20 and to improve the workability of the imaging device 27 by avoiding the visual disturbance of the operator during the cutting operation. It is.

  As shown in FIG. 4, a synthetic resin (for example, urethane rubber) seal cover 40 is disposed between the imaging device 27 and the partition wall 15. That is, the imaging device 27 is held in a state of being fitted into the seal cover 40. The seal cover 40 prevents the image pickup device 27 during sliding from pinching chips in the processing zone and prevents the coolant from seeping into the isolation zone S1.

  Furthermore, a guide port 40 </ b> A that surrounds the imaging device 27 is opened. Then, air is sent out from an air passage (not shown) to the guide port 40A (see the arrow in FIG. 4), and the air is blown out from the gap between the imaging device 27 and the seal cover 40 (see the thick arrow in FIG. 4). .

  Note that, at the position where the imaging device 27 is retracted to the isolation zone S <b> 1 (the standby position indicated by the solid line in FIG. 4), the tip of the imaging device 27 (the portion facing the seal cover 40) is slightly processed zone from the seal cover 40. It is set in advance so that it protrudes to S2 or is flush with the surface.

(Configuration related to the position detection device 18)
As shown in FIG. 5, a flange 66 is connected to the tip of the chuck 12, and the flange 66 has a slightly larger diameter than the diameter of the chuck 12. The flange 66 as an auxiliary body is formed of the same material as the metal (steel) constituting the chuck 12. In addition, a plurality of claws 17 (see FIG. 5) that sandwich the workpiece W shown in FIG.

  On the other hand, a thin step 18A is formed at the tip of the position detection device 18 serving as a reference means, and an optical sensor 68 that detects a distance in the X direction (X direction) is disposed on the Z surface of the step 18A. Has been. An optical sensor 69 that detects a distance in the Z direction (Z direction) is disposed on the X plane of the stepped portion 18A. The optical sensors 68 and 69 are wired with lead wires and connected to a control device including the CPU 60 shown in FIG. The optical sensors 68 and 69 emit light from the light emitting element (synonymous with light emission), and receive the reflected light by the light receiving element (see FIG. 5), so that an object to be measured, for example, the flange 66 shown in FIG. The distance is output to the CPU 60 as detection data (for example, data of light reception time from light emission to reflected light).

  The optical sensors 66 and 69 of the position detection device 18 are arranged so as to face the flange 66 (see the solid line in FIG. 5). That is, the position detection device 18 is slidably disposed over the standby position (the position indicated by the two-dot chain line in FIG. 5) and the detection position (the position indicated by the solid line in FIG. 5), similarly to the imaging device 27 described above. ing. In the position detection device 18 that has moved from the standby position to the detection position during measurement, the optical sensors 68 and 69 face the outer peripheral surface of the flange 66 at a predetermined interval, as shown by the solid line in FIG. The distance (X distance and Z distance) between 69 and the flange 66 is detected.

  As shown in FIG. 5, the imaging device 27 shown in FIG. 3A includes a reference portion (that is, a tip of the stepped portion 18A) 18B of the position detection device 18 and a chip 26A of the bit 26, as shown in FIG. ) Is arranged so that it can be captured (synonymous with single vision). The outer diameter cutting tool 26 is set in advance so as to move to a predetermined position in an area A of the imaging device 27 (referred to as “A frame” in the drawing) when detecting the chip. Reference numeral 25 is set in advance so as to move to a predetermined position in the one-view B area (referred to as “B frame” in the drawing) of the image pickup apparatus 27 when the chip is detected. Further, in this example, the optical sensors 68 and 69 are protruded from the arrangement surface, but the optical sensors 68 and 69 may be flush with or embedded in the arrangement surface.

(Procedure for obtaining initial data of the image capture position according to byte 26)
Based on FIG. 6, the procedure for acquiring the initial vector data of the image capture position relating to the byte 26 will be described. This initial vector data setting mode is a process performed in an adjustment process (at the time of initialization) at the time of machine manufacture in the lathe S shown in FIG.

  Based on this processing data, the CPU 60 shown in FIG. 15 detects and calculates a fluctuating vector value during a calibration cycle or the like. Here, the calibration cycle is to inspect at a predetermined interval forcibly when the lathe S shown in FIG. 1 is operated in order to obtain a compensation value for maintaining the cutting accuracy at a predetermined level. That is, the calibration cycle is an inspection performed after the operation of the lathe S is started.

  First, in the initial vector data setting mode, using the test material 90 shown in FIG. 6, the cutting tool 26 is manually moved into the one viewing A area of the camera 30 (see FIG. 3A). When the byte 26 has not moved into the single vision A area, image processing is performed, and the CPU 60 (see FIG. 15) calculates a difference from the center of the single vision A area shown in FIG. The CPU 60 determines whether or not the offset value is within an allowable range (for example, within 100 μm), and moves the byte 26 within the allowable range if it is outside the allowable range. This process continues until byte 26 is within the acceptable range.

  Then, if it is within the allowable range (the position of the center of the one-view vision A at that time is C), the CPU 60 is based on the image recognition of the reference portion 18B (see FIG. 5) of the position detection device 18 with respect to the tip of the chip 26A. The vector value F1 is calculated. Subsequently, the CPU 60 calculates the vector value F2 of the peripheral edge of the flange 66 with respect to the position detection device 18. That is, the vector value F2 is calculated based on the distances (X distance and Z distance) between the optical sensors 68 and 69 and the flange 66 described above.

  Finally, the CPU 60 calculates the vector value F3 of the test material 90 origin with respect to the position detection device 18. The vector value F3 is a fixed value obtained at the time of initialization. Further, the vector value M at the tip of the tip 26A at the time of machining with respect to the origin of the NC table 50 (see FIG. 15) manually finish-cuts the test material 90 on the workpiece W (see FIG. 1) (cuts with a reduced cutting amount). And based on the position data of the NC table 50 at the time of initialization. Further, at the time of initialization, the vector value WL of the workpiece W (see FIG. 1) with respect to the workpiece origin, that is, the measured value obtained when the test material 90 is cut, is measured with the dimension WL (specifically, the figure) of the test material 90 using, for example, a micrometer. (Values of Wx and Wz shown in FIG. 6).

  At the time of initialization, the vector value M, the NC movement amount C, the vector value F1, the vector value F2, and the vector value WL are substituted into a vector expression (M = C + F1 + F2 + F3 + WL, that is, F3 = M−C−F1−F2−WL), The vector value F3 is calculated. Here, the C value represents the NC movement amount of the tip of the chip 26A at the image recognition point with respect to the origin of the NC table 50 (see FIG. 15) that moves at the time of initialization or the like. The C value is different for each byte, and only one F3 value exists in one turret device. Further, the test material 90 can be applied if it has one diameter and one end surface. Further, the C value and M value of each byte are obtained and recorded in a recording medium such as the RAM 64 shown in FIG.

  On the other hand, during the calibration cycle, the vector value F1 and the vector value F2 are calculated. That is, as described above, the vector value F2 is obtained by sliding the position detection device 18 from the standby position (see the two-dot chain line in FIG. 5) to the detection position (see the solid line in FIG. 5), and then detecting the optical sensor 68 (69. The CPU 60 shown in FIG. 15 calculates the distances (X distance and Z distance) between the optical sensors 68 and 69 and the flange 66 on the basis of the light emitted from (including) and the reflected light (see FIG. 5).

  And the vector M of the workpiece | work W (refer FIG. 1) used as a process target is preset. Specifically, based on the M value calculated from the above-described M = C + F1 + F2 + F3 + WL, the NC table 50 shown in FIG. 15 is moved to the location M shown in FIG.

That is, during the calibration cycle, the relative vector (cutting) of the cutting tool is used based on the detection (position) data of the position detection device 18 without using the test material 90 (including the test piece as in the conventional example) shown in FIG. The position of the entire tool) can be detected accurately. Since the thermal expansion coefficient of the chuck 12 made of steel is 1.15 × 10 ⁻⁵ , the chuck having a diameter of 300 mm increases or decreases by 3 μm when it changes by 1 ° C.

(Operation of this embodiment)
At the time of position detection, as indicated by a solid line in FIG. 5, the position detection device 18 is slid from the standby position to the detection position. Then, after the optical sensors 68 and 69 face the outer peripheral surface of the flange 66 with a predetermined interval, the light emitting elements of the optical sensors 68 and 69 emit light toward the outer peripheral surface of the flange 66. When the light receiving elements of the optical sensors 68 and 69 receive the reflected light from the flange 66, the position detection device 18 detects the position of the flange 66 expanded or contracted by thermal displacement (for example, data on the light receiving time from the light emission to the reflected light). ) To the CPU 60.

  That is, the CPU 60 detects the distances (X distance and Z distance) between the optical sensors 68 and 69 and the flange 66, calculates the vector F2 corresponding to the thermal displacement of the chuck 12, and stores the NC table 50 based on the M value. (See FIG. 6). Therefore, according to the present embodiment, since the position detecting means 18 is configured to face the flange 66 (synonymous with the chuck 12) that is rotatably arranged, the position displaced by the thermal displacement of the chuck 12 can be detected easily and accurately. Can do.

  Further, according to the present embodiment, since the position detection device 18 accurately detects the position corresponding to the thermal displacement of the chuck 12 as the object to be measured, the tip 25A or 26A can be accurately moved to the cutting position. Then, after detecting the position of the object to be measured, the position detection device 18 slides to the standby position.

  Furthermore, according to the present embodiment, since the optical sensors 68 and 69 are wired with lead wires and connected to the CPU 60, the position can be easily derived from the position detection device 18 to the control device (not shown). That is, according to the present embodiment, the position data of the chuck 12 can be output via the position detection device 18 which is a separate member from the rotating chuck 12, so that, for example, a brush holder or the like can be eliminated.

  At the time of chip detection, as shown in FIG. 5, the reference unit 18B of the position detection device 18 and the chip 26A of the bit 26 are placed in the field of view of the camera 30 shown in FIG. At the time of chip detection, as shown in FIG. 4, the imaging device 27 is slid from the isolation zone S1 to the processing zone S2, and the light sources 43 and 44 shown in FIG.

  When detecting the chip 26A of the cutting tool 26 shown in FIG. 5, the image pickup device 27 at the image pickup position (state shown by the broken line in FIG. 4) slides the shutter 38 as shown in FIG. Open the light path. The camera 30 captures an image of the reference unit 18B and the chip 26A of the position detection device 18 that are subjects located in the one vision A area. In other words, since the optical path on the shutter 39 side is blocked, the half mirror 31B reflects the subject light in the single vision A area to the camera 30.

  On the other hand, when the chip 25A of the cutting tool 25 shown in FIG. 5 is detected (in this case, the cutting tool 26 is not in the first viewing A area), as shown in FIG. 3, first, the shutter 38 is slid to change the optical path on the half mirror 31B side. Open. The camera 30 captures an image of the reference unit 18B of the position detection device 18 that is a subject located in the single vision A area. Immediately after imaging, the shutter 38 is closed and the shutter 39 is slid to open the optical path on the full mirror 31A side. The shutters 38 and 39 are switched at a time difference (synonymous with substantially the same time), for example, 0.5 seconds.

  Then, as shown in FIG. 5, the camera 30 captures an image of the chip 25 </ b> A of the bite 25 that is a subject located in the single vision B area. That is, since the optical path on the shutter 38 side is blocked, the full mirror 31A reflects the subject light in the first-view B area to the camera 30. At this time, since the half mirror 31B transmits the subject light reflected by the full mirror 31A, the camera 30 captures an image of only the subject in the single vision B area. And subsequent image processing, collation processing, etc. perform correction processing of the cutting position described in Japanese Patent Application No. 2009-38185, for example.

  In this example, the position detection device 18 is slidably arranged. However, the position detection device 18 may be always fixed to the detection position (see the solid line in FIG. 5). The detection means according to the present invention can be similarly applied to a non-contact type air micrometer, a contact type differential transformer, and the like in addition to the optical sensor. In this case, the detecting means may detect the position displaced by the thermal displacement of the chuck even when the object to be measured such as a chuck is stationary or rotating.

  Further, the edges of the chips 25A and 26A shown in FIG. 5 can be obtained using, for example, a seek line for cutting lines described later. The seek line is a line segment having a free length and inclination set in the two-dimensional virtual screen, and obtains the position of the edge with respect to the center position in the line direction.

  Embodiment 2 of the position detection apparatus according to the present invention will be described with reference to FIGS. However, substantially the same parts as those of the position detector 18 shown in FIG. 5 of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted or simplified, and mainly the different parts will be described. In the second embodiment, the same optical sensors 68 and 69 as in the first embodiment are arranged (see FIG. 8).

  In the second embodiment, as shown in FIG. 8, a contact-type temperature sensor 70 is arranged in parallel with an optical sensor 69. That is, the present embodiment is an example in which the temperature sensor 70 detects the temperature of the chuck 12.

  In the temperature sensor 70, a cylindrical contact 71 is slidably disposed, and when the contact 71 comes into contact with an object to be measured, for example, the flange 66, temperature data of the flange 66 is output to the CPU 60 (see FIG. 15). . That is, the slidable contact 71 is in contact with the flange 66 and is pushed into the temperature sensor 70 to be immersed therein.

  In the present embodiment, when the position is detected, the contact 71 of the temperature sensor 70 contacts the flange 66, so the temperature sensor 70 outputs the temperature data of the flange 66 to the CPU 60. That is, according to the present embodiment, the temperature sensor 70 also detects position data (synonymous with displacement data based on the expansion rate or contraction rate) corresponding to the temperature of the flange 66 (chuck 12) that is the object to be measured. Therefore, the chip 25A or 26A can be moved to the cutting position with high accuracy for cutting. Other configurations and operational effects are the same as those of the first embodiment. The temperature sensor can be similarly applied to a non-contact type in addition to a contact type.

  In each of the above embodiments, as shown in FIG. 9, the position detection device 18 is arranged so that the sensors 68 and 69 can be opposed to the outer peripheral surface of the chuck 12 with a predetermined interval without providing the chuck 12 with a flange. It may be arranged. In each of the above embodiments, only one of the optical sensors 68 and 69 may be detected. For example, only the optical sensor 68 in the X direction may be disposed. Furthermore, the moving direction of the position detecting device 18 is not limited to the horizontal direction or the vertical direction in the drawing, and any moving direction such as a combination thereof may be used.

(Configuration of blade edge cleaning device)
Hereinafter, based on FIG. 10 thru | or FIG. 14, the structure regarding the to-be-cleaned object cleaning apparatus which cleans to-be-cleaned objects, such as a blade edge | tip, is demonstrated. 5 that are substantially the same as those of the position detection device 18 shown in FIG. 5 of the first embodiment are denoted by the same reference numerals, description thereof is omitted or simplified, and different portions are mainly described.

(Technical field)
This technical field relates to a cleaning object cleaning device that cleans a cutting edge of a cutting tool, such as a tip, and a cutting machine that includes the cleaning object cleaning device.

(Background technology)
Japanese Patent Application Laid-Open No. 10-96616 discloses a configuration in which a robot control device in which an air gun is arranged is moved around a cutting tool, for example, a mill, and chips and the like adhering to the chip of the mill are removed by the air gun. (See paragraph number “0060”). In the above publication, a slit is projected onto a chip from a light projection window of a structure light unit, and camera shot (that is, image processing) is performed through the photographing window to automatically inspect wear of a tool chip.

(Issue to solve)
In the above-mentioned publications and the like, when inspecting the cutting tool for wear after the above-described image processing, it is necessary to clean as much fine chips as possible. Also, when detecting the cutting position of a cutting tool by thermal displacement (including, for example, Patent Document 1), for example, even when detecting the position using a certain reference line, fine chips and the like are removed as much as possible. There is a need to.

  In the above publication, fine chips and the like adhering to the chip of the mill cannot generally be removed simply by blowing them gently with a normal air gun, so that it is difficult to accurately detect the position of the cutting edge of the cutting tool.

  Therefore, the cleaning object cleaning device described below effectively removes fine chips adhering to the cleaning object, such as a cutting tool, and the cutting machine equipped with the cleaning object cleaning device includes a cleaning object, such as a cutting tool. The cutting position can be detected efficiently. For example, the cleaning means that faces the object to be cleaned (such as a cutting tool) is an object cleaning device that moves relative to the object to be cleaned based on movement trajectory data along the outer shape of the object to be cleaned.

  Also, a cleaning object cleaning device, an imaging unit that captures an image of the subject, and an imaging unit that captures an image of a cutting tool that is an object to be cleaned as the subject and calculates movement trajectory data of the cutting tool based on the image data. And a control means for relatively moving the cutting tool or the object to be cleaned based on the movement trajectory data.

  As shown in FIGS. 10 to 13, the cylindrical air nozzle 88 is positioned above the position detection device 18, and a tapered tip end 88 </ b> A is located near the step portion 18 </ b> A of the position detection device 18. Has been placed. The diameter of the tip end port 88A is, for example, a diameter of 1.5 mm, and the effective air area is set in advance to, for example, about 2 mm. That is, since a compressor (not shown) is connected to the air nozzle 88, air from the compressor is ejected from the tip end port 88A. Note that the distal end portion 88A is formed to be bent toward the tip 26A of the cutting tool 26. The blade edge cleaning device includes an air nozzle 88 and a compressor (not shown).

(Operation of the blade cleaning device)
Immediately before executing the image processing, the blade edge cleaning device causes the outer diameter cutting tool 26 to face the front end 88A of the air nozzle 88, as shown in FIG. Next, as shown in FIGS. 11A to 11C, the tip 26 </ b> A of the cutting tool 26 has a tip line 88 </ b> A of the air nozzle 88 with the contour line of the tip 26 </ b> A (synonymous with a position where the workpiece is actually cut). It moves toward the lower part (X direction) sequentially from the upper part of the cutting surface corresponding to. At this time, the tip 26A moves in a curve with a predetermined interval, for example, 2 mm, with respect to the tip end 88A of the air nozzle 88 that continues to blow out air.

  Subsequently, as shown in FIGS. 11D and 11E, the chip 26A moves in a curve in the Z direction on the lower surface of the chip 26A corresponding to the contour line. At this time, air continues to be ejected from the tip opening 88A of the air nozzle 88. That is, in this example, a part of the object to be cleaned is intensively cleaned along the outline of the tip 26A, for example, compared with a case where fine chips adhering to the blade edge are blown away with a normal air gun. Even powder can be removed.

  Finally, the cutting tool 26 is moved so as to correspond to the reference portion 18B of the position detecting device 18, as indicated by a two-dot chain line in FIG. And the camera 30 shown to FIG. 3 (A) images the reference | standard part 18B and chip | tip 26A which are located in the one vision A area. In this example, the blade edge cleaning device including the air nozzle 88 blows away chips and the like over a wide area near the cutting surface corresponding to the contour line of the tip 26A.

  Therefore, according to this example, chips and the like in a sufficient range in the cutting process of the chip 26A can be removed, so that the chip 26A in a clean state where chips and the like are not attached can be image-processed. Here, the byte 26 moves so as to draw the above-described curved movement locus, but this movement locus data is recorded in advance in a recording medium of the RAM 64 (see FIG. 15). Then, the CPU 60 shown in FIG. 15 moves the bite 26 based on the movement trajectory data.

  In addition, when CPU60 which is a calculating means or a control means detects that the chips etc. have adhered to the chip | tip 26A after image processing, all the processes or only an adhesion location are repeated several times or until chips etc. are removed. The above-described cleaning operation may be repeated. Further, in this example, at the time of cleaning, in addition to the cutting tool 26, the air nozzle 88 may be relatively movable or only the air nozzle 88 may be moved. Further, the cleaning timing can be arbitrarily changed during a calibration cycle.

  On the other hand, in the case of the tip 25A of the outer diameter cutting tool 25, as shown in FIGS. 12A to 12C, the tip end 88A of the air nozzle 88 is substantially at the center of the cutting surface corresponding to the contour line of the tip 25A. From the top to the top (slant in the upward direction). At this time, the tip 25 </ b> A moves in a curved manner with a predetermined interval with respect to the tip opening 88 </ b> A of the air nozzle 88. Subsequently, as shown in FIGS. 12D and 12E, the chip 25A moves in a curvilinear direction downward (X direction) from the upper part of the chip 25A corresponding to the contour line. Other functions and effects are the same as in the example of FIG.

  As another example, the air nozzle 88 shown in FIG. 13 may be formed by bending the cutting tool 24 downward from the upper side toward the tip 24A. In this case, since the tip opening 88A can blow air over the entire surface of the chip 24A, even fine chips adhering to the chip 24A can be effectively cleaned. Further, in the present embodiment, the bending direction, the diameter, or the compression force of the compressor (specifically, adjustment by a compression valve) can be arbitrarily changed.

  As yet another example, a tapered brush member 89 shown in FIG. 14A is rotatably arranged, and a plurality of brushes 89 A are arranged at the tip of the brush member 89. That is, a variable type motor (not shown) is connected to the brush member 89, and this motor rotates the brush member 89 over a range of high speed to low speed. Note that the motor may have only a constant speed. Other configurations and operational effects are the same as in the example of FIG.

  In this example, in addition to the air nozzle 88 or the brush member 89, a laser or an ultrasonic wave may be used. Further, the movement trajectory data of the air nozzle 88 and the like described above is generated based on the above-described 50 μm seek line group of the blade edge. That is, the CPU 60 generates (that is, calculates) a contour line of the cutting edge based on a plurality of seek line groups, and uses the contour line as a movement locus. Furthermore, as a method for acquiring a contour line, for example, the contour of an object to be cleaned such as a blade edge can be acquired by a so-called boundary tracking method. These data are acquired at the time of the adjustment process at the time of machine manufacture mentioned above.

(Image recognition processing method)
The cutting tool image recognition processing method according to the present embodiment will be described in detail with reference to FIGS.

(Technical field)
This technical field relates to an image recognition processing method for recognizing a subject, for example, a cutting tool, and a machine tool using the image recognition processing method.

(Background technology)
Japanese Patent Application Laid-Open No. 4-232407 discloses a method for measuring the width of a parallel beam of a tool received by a light receiving means and obtaining the outer shape of the tool from the relationship between the rotation angle of the tool and the measured value (see the summary). ). In the above publication, the width of the parallel light beam related to the tool is measured, and the outer shape of the tool is obtained from the relationship between the rotation angle of the tool and the measured value, so that it is possible to identify the deformation location and detect the degree of deformation. . In the above publication, since the outer shape of the tool can be easily obtained, the work time is short, and automation is possible.

(Issue to solve)
In the above-mentioned publication, it is possible to detect the location of deformation and the degree of deformation, but since a method for accurately recognizing the image such as the degree of deformation is not disclosed, whether or not there is any trouble in cutting based on the degree of deformation or the like. It cannot be detected. In some cases, chips or the like are welded to the rake face of the cutting tool and expand (the expanded state is referred to as a constituent cutting edge). In this case, since the cutting surface of the workpiece becomes rough or the dimensions change, it is necessary to detect and remove the constituent cutting edges as early as possible.

  Therefore, when recognizing with an optical sensor, a camera, or the like, depending on the direction, it may not be possible to recognize whether it is a constituent edge. In addition, when chips or the like adhere to a rake face (ie, a face outlined by a cutting line) and there is a trouble in cutting, it is necessary to stop the machine immediately. However, even if chips or the like adhere to a place unrelated to the cutting surface, there is no need to stop the machine because it does not hinder cutting.

  Therefore, this image recognition processing method can accurately recognize the deformation state of the cutting tool and can detect whether or not there is any trouble in cutting.

(Configuration for control system of lathe S)
As shown in FIG. 15, the lathe S includes a CPU 60, ROM 62 and RAM 64, which are nonvolatile memories, a motor driver 51 and NC motor 52 arranged on the NC table 50, and a motor driver 53 arranged on the turret device 20. , A turret motor 54, an operation unit 56, a display unit 57, and a buzzer 58. The CPU 60 that is the collating unit and the correcting unit controls the overall operation of the lathe S, and performs processing based on the operation when, for example, an operation key arranged on the operation unit 56 is operated. The CPU 60 is connected to a camera 30 that constitutes a part of the imaging means, and image data captured by the camera 30 is input to the CPU 60.

  The ROM 62 as recording means records a program for controlling various processes on the lathe S, and the lathe S is controlled by the program. The RAM 64 as recording means has a recording area for reading and writing various data, for example, an image data area 65, and image data and the like are recorded in the image data area 65. The motor 52 or 54 rotates via the motor driver 51 or 53 based on the drive signal of the CPU 60. The display unit 12 serving as a display unit displays image data captured by the camera 30 and the like. A buzzer as a warning means outputs a warning sound.

(Byte image processing mode)
The byte image processing mode will be described with reference to the flowchart of FIG. In step 162, it is determined whether or not the cutting edge is broken. If step 160 is negative, it is determined in step 164 whether or not the blade edge is expanded (such as a component blade edge or chip adhesion). If step 164 is negative, it is determined in step 166 whether or not the blade edge is worn. These determination methods use a seek line, which will be described later.

  When step 166 is affirmative, that is, when it is determined to be wear, it is determined at step 168 whether or not the wear is equal to or greater than a set value (for example, 20 μm). When step 168 is affirmative, that is, when the value is equal to or greater than the set value, in step 170, the friction amount data is recorded in the RAM 64 (that is, data for maintenance or the like).

  Then, when step 162 or step 164 is affirmative, or when step 168 is negative or after the processing of step 170 is completed, the operation of the lathe S is forcibly stopped in step 172 (for example, cutting is performed until the cutting tool is replaced). Including fail-safe measures such as prohibition of driving) and warning in step 174.

  Specifically, a warning display or buzzer 58 is activated on the display unit (see FIG. 13) to output a warning sound or a warning sound from a speaker (not shown). The operator is prompted to replace the byte by the warning. If foreign matter such as chips adheres to the imaged field of view, the CPU 60 can set an error as an image recognition function, so that fail-safe treatment can be performed. Further, if it is determined in step 166 that the cutting edge is worn, the CPU 60 stops the operation of the lathe S for chip replacement even if it is equal to or less than the set value.

  If step 166 is negative, that is, if it is determined that the cutting edge is not worn, in step 176, the CPU 60 determines whether or not the displacement of the cutting edge is equal to or greater than a set value (for example, 100 μm). The displacement of the blade edge is determined by detecting the total position of the cutting line in FIG. 7, and the wear of the blade edge may be included in addition to the thermal displacement.

  If step 176 is affirmative, that is, if it is equal to or greater than the set value, in step 178, the interpolation data is recorded in the RAM 64 based on the displacement data at the time of measurement (that is, the data for maintenance etc.). If step 176 is negative or after the processing of step 178, feedback processing is performed in step 179 to perform compensation processing.

  Hereinafter, an image recognition processing method for a cutting tool will be described with reference to FIGS.

(Initial image data method for cutting tools)
The initial image data method is an image recognition process performed by imaging with the imaging device 27 shown in FIG. 1 when a new cutting tool is set on the turret tool post 21 (see FIG. 1). Note that with the 5 million pixel camera 30 (see FIG. 3A), image recognition is performed with an accuracy of ± 0.25 μm (= 1/34 pixel) for positioning of the edge of the chip 26A shown in FIG.

  In other words, even with an optical system camera with 5 million pixels (actual size per pixel is 8.6 μm), the recognition accuracy of recent image processing technology has been improved, so that it is possible to fully recognize chip breakage and wear. In addition, the temperature of the chuck 12 (see FIG. 1) can be measured in units of 1 ° C. Here, the square frame in FIG. 17 is a blade edge detection area used when detecting the tip (ie, rake face) of the tip 26A.

  First, as shown in FIG. 17, the initial image data method of the chip 26A is obtained by arranging a plurality of seek lines (means for obtaining the position of the edge portion contour) CL along the contour of the chip 26A, for example, at regular intervals of 40 μm. It is set in advance. At this time, the length of the seek line CL is set to be a reference length centered on the contour line, that is, a half length of 50 μm (the total length is 100 μm), and the seek line CL is set to be perpendicular to the contour line. Here, a template (means for obtaining the position of the blade edge) constituted by the seek line CL group (means for recognizing the position of the contour portion of the blade edge) shown in FIG. 17 is referred to as an original template serving as a reference image.

  In this example, the reason why the reference length is set to 50 μm, for example, is to recognize the chip 26A chipping or the size of adhesion of chips (ie, the maximum length) as 50 μm or more or less. In other words, this is for avoiding movement of the position of the subject (so-called object vector) when chips or the like adhere to the chip 26A as the subject and the outer shape changes.

  Therefore, when the edge position of the seek line CL (synonymous with the position of the intersection on the contour line of the chip 26A) deviates more than or less than half the seek line CL, the target seek line CL is error-processed (synonymous with invalidity). This is because it is not included in the calculation of the object vector. Here, object positioning by pattern matching (synonymous with collation) calculates an object vector only when the deviation is within the seek line CL, and allows errors up to a certain number of seek lines CL. Yes.

  After pattern matching, for each seek line CL, the difference on the seek line CL between the midpoint (half-length 50 μm) and the edge position is calculated. This difference indicates the degree of deformation of the subject outline with reference to the initial image data setting of the subject (for example, byte). This criterion also applies to the case of a cutting line vector value (hereinafter referred to as a relative value) with respect to the original template.

  Note that, according to the above reference, even if the position of the cutting tool itself is displaced by thermal expansion of a ball screw (not shown), the difference on these seek lines CL does not change. In addition, the deformed part of the tool, for example, the chip missing part or the attached part of the chips or the like is very low in terms of the ratio of the total number of seek lines CL, so that the influence on the displacement of the entire subject is small.

  In this example, the breakage of the cutting tool and the adhesion of chips and the like are detected based on the difference value on the seek line CL described above. In this example, so-called multi-step pattern matching (hereinafter referred to as “MS”) pattern matching technique is applied to subject position recognition, but other than this, pattern matching based on normalized correlation is used. May be. In this example, the seek line CL that constitutes the MS pattern matching template is used for each edge recognition. However, in addition to this, a caliper line for edge detection (a modification of the seek line CL) is applied. Also good.

(Acquisition method of cutting line data)
Based on FIG. 18 thru | or FIG. 20, the acquisition method of cutting line data is demonstrated. As shown in FIG. 18, a plurality of seek lines (means for obtaining a cutting line) CL related to the X-direction cutting line are generated at equal intervals of, for example, 10 μm. The X-direction cutting line is a straight line drawn in the horizontal direction from the lowest edge position of the seek line CL group having the lowest edge position. That is, the X direction cutting line is a horizontal tangent to the outline of the tip 26A.

  As shown in FIG. 19, the seek line CL related to the Z-direction cutting line is also generated in the same manner as the X-direction cutting line described above. That is, the Z-direction cutting line is a perpendicular tangent to the outline of the tip 26A. Then, the positions of the X-direction cutting line and the Z-direction cutting line are recorded in the RAM 64 shown in FIG. 15 as difference amounts with respect to the original template.

  As shown in FIG. 20, a cutting line in the direction of 30 degrees with respect to the horizontal can be generated. That is, in order to cut the tapered surface into the workpiece, a cutting line having a specific angle, for example, 30 degrees, is generated in order to calculate the movement trajectory of the cutting tool. Thereby, a taper surface can be processed accurately. In this example, the locus of the cutting tool may be set geometrically from the X-direction cutting line, the Z-direction cutting line, and the cutting tool nose.

  Here, the position (vector) of the cutting line has a significance of a relative vector and an absolute vector, and the absolute vector is the sum of the wear of the cutting tool and the thermal strain of the entire machine. Then, the absolute vector is compensated by the NC table 50 (see FIG. 15), and the blade wear and the mechanical thermal displacement are feedback compensated. That is, the correction data of the NC table 50 is processed based on the absolute position of the cutting line.

  On the other hand, the relative vector of the cutting line is based on the position of the cutting line relative to the pattern-matched position in the original template, and the calculation of the wear amount limit value of the cutting tool (inward movement) and the attachment of chips and the detection of the constituent cutting edges (outside) Used for the processing of (moving to). Note that the CPU 60 shown in FIG. 15 calculates the wear amount of the cutting tool = the cutting line / the entire position of the cutting tool (the relative position of the cutting line).

(Detection process during calibration cycle)
First, as shown in FIG. 21, when detecting a missing part of the cutting tool, the difference on the seek line CL is recessed toward the inner side of the tip 26A. The CPU 60 (see FIG. 15) makes a determination. The threshold value is, for example, a case where the depression amount is 30 μm or more and the width is continuous over five (approximately 200 μm) seek lines CL. This threshold value can be arbitrarily changed, and also when only one of the depression amount and the width corresponds, it may be a defect.

  In this example, the seek line CL group (see FIG. 17) of the original template and the image data at the time of the calibration cycle are collated, and a change location (synonymous with a different location) of the seek line CL can be detected. That is, according to this example, it is possible to detect a chip 26A defect only by pattern matching with the original template (see FIG. 17).

  Second, as shown in FIG. 22, when detecting a protrusion on the cutting tool, the difference on the seek line CL protrudes toward the outside of the chip 26A. Therefore, the CPU 60 determines whether the protrusion amount and the width are equal to or greater than a threshold value. Judge. The threshold value is, for example, when the protrusion amount is 20 μm or more and the width is continuous over three seek lines CL (approximately 120 μm) or more. According to this example, as in the example of FIG. 21, it is possible to detect a chip 26A defect only by pattern matching with the original template (see FIG. 17).

  Third, when detecting whether or not the amount of wear of the cutting tool is greater than or equal to a threshold value, a change in the relative position of the cutting line with respect to the original template is detected. That is, the CPU 60 compares the image data at the time of the calibration cycle with the original template (see FIG. 17) and the image data (see FIG. 23), and the wear position at the relative position of the cutting line is a threshold value (for example, 20 μm). In the case of the above (see FIG. 24), it is determined that the amount of wear of the blade is excessive (the life of the blade). In this example, by using the seek line CL group (see FIG. 17) of the original template and the cutting line, it is possible to detect the excessive wear amount of the cutting tool.

  Fourth, as shown in FIGS. 25 and 26, when detecting the protrusion of the cutting tool (adhesion of the constituent cutting edge or chips), a change in the relative position of the cutting line with respect to the original template is also detected. That is, when the change in the relative position of the cutting line protrudes toward the outside of the chip 26A, the CPU 60 determines whether or not the set value (for example, 5 μm) or more. If it is greater than or equal to the set value, it is determined that foreign matter such as chips adheres to the chip or abnormal deformation of the cutting tool occurs.

  This process detects not only the change with respect to the relative position of the cutting line at the initial setting but also the change with respect to the cutting line position at the time of the current detection during the calibration cycle. This detection is based on the cutting line with the tip 26A retracted inward due to wear.

  Further, the CPU 60 determines whether or not the relative change amount with respect to the cutting line position at the time of the current detection during the calibration cycle is equal to or greater than the above-described set value (synonymous with byte data) and the protrusion amount and the width are equal to or greater than a threshold value. The threshold value is, for example, when the maximum protrusion amount is 50 μm or more and the width t is continuous over 200 μm or more (see FIG. 25). In this case, the CPU 60 determines that “the suspicious ant of the component edge”.

  The CPU 60 detects the protruding amount of the constituent blade edge with the width t. That is, when the constituent cutting edge is generated, a continuous shape having a width t with a portion protruding from the cutting tool is obtained. And when it is not the structure cutting edge mentioned above, CPU60 judges that foreign materials, such as a chip, adhere to a chip | tip (refer FIG. 26). That is, according to the present example, the projection of the cutting tool (adhesion of the constituent cutting edge or chips) can be detected by using the seek line CL group (see FIG. 17) and the cutting line of the original template.

(Setting method of seek line CL)
As shown in FIG. 27, the seek line CL is generated in a direction perpendicular to the desired cutting line (Z-direction cutting line in FIG. 27) from the inside to the outside of the chip 26A. The seek lines CL are generated at equal intervals of, for example, 10 μm from the center toward the upper end and the lower end (see FIG. 27).

  Further, when the start point position of the seek line CL protrudes from the contour line of the original template (see the third and fourth lines from the lowest end in FIG. 27), the protrusion amount is set to about 20 μm, for example. Further, when the entire seek line CL is separated from the original template (see the two bottom lines in FIG. 27), the seek line CL is generated so as to be within two. These two seek lines CL are set to have the same starting point position, for example, the third position from the lowermost end and the same length.

  In this example, when the seek line CL group as described above is generated, a range that does not affect the cutting is set, so that the foreign matter separated from the start point position of the seek line CL can be excluded from detection. That is, according to this example, since the detection range that affects cutting is set in the seek line CL group, it is possible to specify a detection target that may cause a problem in cutting. Note that the foreign matter shown in FIG. 27 is a floating substance floating in the air.

(Example of non-detection target range)
First, as shown in FIG. 28, the chips A, the abnormal projections of the cutting tool, and the chips B are all located on the inner side of the cutting line in the Z direction, and thus are not detected objects. That is, foreign matter and the like located inside the cutting line are in a range that does not affect cutting, and thus are not detected. The CPU (see FIG. 15) detects (recognizes) the outer shape of the chip 26A based on the edge position of the seek line CL. Further, like the seek line CL1 (see FIG. 28), the seek line CL having no edge portion (invalid) is excluded from detection.

  Since the first edge portion of the foreign matter A is near the cutting line and the last edge portion is located outside (right side), the seek line CL2 is excluded from detection. In other words, since the outer shape of the chip is a single body, foreign objects and the like that are separated from each other become non-detection objects. The foreign objects B, C, and D are out of the seek line CL (that is, there is no edge portion), and thus are not detected objects.

  On the other hand, a tip portion (referred to as a reference portion) from the reference line shown as a virtual line of the chip 26A affects cutting. When chips or the like adhere to the reference portion, the CPU 60 (see FIG. 15) is a detection target. In this example, processing is performed from the center (see FIG. 28) of the seek line CL group to the upper end and the lower end. For example, when a seek line exists below the invalid seek line, the seek line is excluded from detection.

  Next, when one end of a long chip as shown in FIG. 29 adheres to the chip 26A, the final edge of the seek line CL12 is unknown, so the CPU 60 sets it as a detection target. In this case, the other end of the long swarf does not affect the reference portion of the chip 26A, but is deliberately set as a detection target. If the CPU 60 determines that the object is a detection target, the CPU 60 determines that it is abnormal, and performs processing such as operation stop in step 172 of FIG.

  Finally, the CPU 60 calculates an absolute position (synonymous with an absolute vector) of a cutting line (including cutting lines in the X direction and the Z direction). That is, the CPU 60 feeds back the change (including the change amount) of the absolute vector of the cutting line to the next cutting cycle.

(Absolute vector detection method of chip 26A)
The absolute vector detection of the chip 26A is performed by using the following image data. This image data includes, for example, a comprehensive detection area and a blade edge detection area. As shown in FIG. 30, the total detection area (refer to the square frame in the solid line portion) is an imaging region showing the chip 26A and is used when the chip 26A is detected as a whole. The blade edge detection area (refer to a two-dot chain line square frame) is used when detecting the tip of the tip 26A.

  As described above, in the camera 30 of 5 million pixels (see FIG. 3), the recognition accuracy of positioning such as the edge of the chip described in FIG. 31A is ± 0.25 μm (= 1/34 pixel). The image can be recognized with high accuracy, and the image can be recognized with an accuracy of ± 0.45 μm (= 1/19 pixel) as the recognition accuracy of the cutting line Lcm or Lbm described with reference to FIGS. As described above, the solid line partial frame (square frame) in FIG. 31 is a comprehensive detection area, and the two-dot chain line partial frame (square frame) in FIG. 31 is a blade edge detection area.

  First, as shown in FIG. 31A, the edge of the chip 26A is obtained by setting a plurality of seek lines La. The edges of the chip 26A before and after use are obtained and pattern matching is performed. If the positions of the edges differ below a threshold value, it is determined that the chip 26A is broken. On the other hand, when the positions of the edges are different from each other by a threshold value or more, it is determined that the chips 26A are inflated (also referred to as a component cutting edge) by welding chips. Note that the threshold value has a width of 20 μm, for example, and the width can be arbitrarily changed.

  The tip nose can also be determined using the seek line. That is, as shown in FIG. 31B, a plurality of seek lines Lb directed downward are set at predetermined intervals, and a seek line Lbm having a maximum luminance value (a point changing from dark to bright) is the lowest point. The X direction cutting line is obtained. Similarly, as shown in FIG. 31C, a plurality of seek lines Lc directed to the left are set at predetermined intervals, and a seek line in which the maximum value of luminance (a point changing from dark to bright) is the leftmost point. Lcm is calculated | required and it is set as a Z direction cutting line.

  Next, as shown in FIG. 31D, a distance Rz between the X direction cutting line Lbm and a line Lbp parallel to the X direction cutting line Lbm and passing through the edge Ec of the Z direction cutting line Lcm is obtained. Similarly, a distance Rx between the Z direction cutting line Lcm and a line Lcp parallel to the Z direction cutting line Lcm and passing through the edge Eb of the X direction cutting line Lbm is obtained. The larger of the distance Rz and the distance Rx is set as the nose. If the nose of the tip 26A after use is greater than the set value than the nose of the tip 26A before use, it is determined that the tip 26A is worn.

  In the above-described image recognition processing method, the seek line group of the original template and the image data at the time of the calibration cycle are collated, and the change portion of the relative position of the seek line is detected. The image recognition processing method detects a change in the relative position of the cutting line with respect to the original template when detecting whether or not the wear amount of the cutting tool is equal to or greater than a threshold value. Further, the image recognition processing method detects a change in the relative position of the cutting line with respect to the original template even when detecting the protrusion of the cutting tool (adhesion of the constituent cutting edge or chip).

  The image recognition processing method detects a change with respect to the relative position of the cutting line at the initial setting, and also detects a change with respect to the cutting line position at the time of the current detection at the calibration cycle. In the image recognition processing method, the collating unit calculates whether the relative change amount with respect to the cutting line position at the time of the current detection in the calibration cycle is a set value or a threshold value.

  A machine tool that uses the image recognition processing method includes an image recognition processing device that performs the above-described processes or a process that combines a plurality of these processes, an imaging unit that images a subject, and the imaging device images a cutting tool as the subject. A collating unit that collates the original template and the image data at the calibration cycle based on the image data, and a control unit that feeds back the operation stop or the collating data to the next cutting cycle based on the collation result of the collating unit. It is.

  The present invention is not limited to the short-axis lathe described in the first and second embodiments. For example, various cutting machines such as a two-axis face lathe or a milling machine (machines that move a cutting tool and a workpiece relatively to perform machining). ).

  DESCRIPTION OF SYMBOLS 12 ... Chuck (measuring object), 18 ... Position detection device (reference means), 18B ... Reference part (subject), 25 ... Inner diameter cutting tool (subject), 25A ... Cutting edge, 26 ... Outer diameter processing bit (Subject), 26A ... blade edge, 27 ... imaging device (imaging means), 30 ... camera, 60 ... CPU (collation means, calculation means, correction means, image recognition processing device), 62 ... ROM (recording means), 64 ... RAM (recording means), 66 ... flange (auxiliary body), 68, 69 ... optical sensor (position detecting means), 70 ... temperature sensor, 90 ... test material, S ... lathe (cutting machine), W ... work

Claims (8)

  A detecting means for detecting a position displaced due to a thermal displacement of an object to be rotatably arranged is provided, and the detecting means detects a position facing the object to be measured in at least one of a stationary state and a rotating state. A device for detecting the position of an object to be measured.   2. The object position detecting device according to claim 1, wherein an auxiliary body made of the same material as the metal constituting the object to be measured is arranged to be connected to the object to be measured, and the auxiliary means is used by the detecting means. An object position detecting device for detecting a position displaced due to thermal displacement of the object.   3. The device position detection apparatus according to claim 1, wherein the detection means is moved with respect to the device to be measured.   4. The device position detection apparatus according to claim 1, wherein the detection unit includes an X direction sensor that detects a position in the X direction of the device to be measured, and a Z direction that detects a position in the Z direction. 5. A device for detecting a position of an object to be measured, wherein at least one of the sensors is used, and the sensor is disposed on a reference means.   5. The device position detection device according to claim 1, further comprising a temperature sensor that detects a temperature of the device to be measured. 6.   A cutting machine provided with a measured object position detecting device, wherein a cutting position of a cutting tool is calculated based on detection data by the measured object position detecting device according to any one of claims 1 to 5. A measurement object position detecting device according to any one of claims 1 to 5, an imaging means for imaging a subject, and a reference unit for measuring a position error of the imaging means in the reference means according to claim 4,
An object position detecting apparatus, wherein the imaging means images the reference portion and the cutting tool in the same imaging area as a subject, and calculates a cutting position of the cutting tool based on the captured image data. Cutting machine equipped. 6. The device position detecting device according to claim 1, the optical path separating means for separating optical paths corresponding to subjects at different imaging positions, and the same optical path in the optical path separating means. 5. An imaging device comprising: an imaging device, wherein the optical path separation means intercepts the optical path at the other imaging position when imaging the subject at one imaging position; and the reference means according to claim 4, A reference unit for measuring the position error,
The imaging apparatus images the reference unit at one imaging position in the one optical path and the cutting tool at the one imaging position as a subject in the same imaging area, or the one in the one optical path. The reference portion at the imaging position is imaged as a subject, and the cutting tool at the other imaging position in the other optical path is imaged with a time difference of optical path switching, and the cutting position of the cutting tool is calculated based on the captured image data. A cutting machine provided with an object position detecting device.

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