JP5366124B2 - Cutting tool inspection system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cutting tool inspection system which can always highly accurately process an image of a chip of a cutting tool picked up by a camera and precisely inspect the cutting tool. <P>SOLUTION: The cutting tool inspection system 30 picks up the images of a reference mark M positioned at an inspection position close to the chip C and the chip C in the same visual field by a camera 54 to inspect the state of the chip C. The image processing of the chip C is carried out on the basis of the reference mark M. Since a reference mark rod 40 is attached to, for instance, a spindle stock 10 to which a workpiece is attached, even when the camera 54 shifts from the inspection position due to an influence of heat or an image pick-up direction is inclined, the reference mark M does not directly receive the influence. Thus, the position or direction of the camera does not need to be highly accurately adjusted as in a usual system. An image processing accuracy can be constantly maintained to a state of a high level, the cutting tool can be precisely inspected and an accuracy of a cutting work by the cutting tool can be improved. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a cutting tool inspection system that images a cutting tool provided in a machine tool and inspects the state of the cutting tool, such as breakage or wear.

  Conventionally, when inspecting the state of a cutting tool mounted on a machine tool such as a lathe, milling machine, turning center, etc., for example, chip breakage or wear, a mechanical lever type displacement sensor is arranged in the machining zone of the machine tool, The tip is brought into contact with the tip of the lever before and after cutting, and the displacement of the lever is measured and inspected. However, since only one surface of the chip can be inspected by one contact, it is necessary to make contact at least twice in order to inspect a multi-surface chip, and it takes an inspection time. In addition, if the tip is brought into contact with the tip of the lever at a high speed, the tip and the tip of the lever may be damaged due to an impact. In addition, cutting powder generated by cutting is scattered in the machining zone of the machine tool. However, if cutting powder enters the movable part that displaces the lever, the movement may be hindered and the displacement measurement accuracy may decrease. Therefore, it was necessary to perform maintenance frequently, which was troublesome. Further, since the mechanical lever type displacement sensor has a displacement measurement accuracy of several tens of μm, there is a limit to the improvement of the inspection accuracy.

  As a cutting tool inspection system that solves such a problem, there is a system that images the tip end of a cutting tool using a camera and performs image processing on the image using a computer to inspect the state of the chip. For example, in Patent Document 1, the translation position and the rotation position of the cutting tool are controlled so that the tip of the cutting tool comes to a predetermined inspection position, and the chip at the inspection position is photographed from a predetermined direction. To obtain index data representing the size of chip defects. A cutting tool inspection system is disclosed in which the index data is compared with a predetermined criterion in the system to automatically determine the necessity of tip replacement. Patent Document 2 discloses a cutting tool inspection system in which a cutting tool is rotated or moved, a plurality of chip states are captured by a camera, and an inspection is performed by selectively using a focused image from the plurality of images. Is disclosed.

According to these cutting tool inspection systems, since the entire multi-faceted chip can be imaged at once using a camera and processed by image processing, the multi-face shaped chip can be inspected several times using the lever-type displacement sensor. Therefore, the inspection time can be shortened compared with the case where the contact is made at a low speed over the distance and the displacement is measured and inspected. A mechanical lever-type displacement sensor requires a movable part for displacement measurement, but an optical camera does not require such a mechanical movable part. Even if it is installed, it is difficult to be affected by cutting powder that is generated and scattered by cutting, and the maintenance work can be simplified. An optical camera can inspect with high accuracy of several microns or less by increasing the resolution.
Japanese Patent Laid-Open No. 10-96616 (paragraphs 0007, 0009, FIGS. 1 and 2) Japanese Patent Laid-Open No. 2001-227312 (paragraph 0011, FIG. 1)

  In the cutting tool inspection system using the camera described above, the camera is moved from the inspection position to the retracted position so that the camera does not interfere with the cutting tool or the like during the cutting process, and then the camera is returned from the retracted position to the inspection position. Yes. At this time, in order to perform high-accuracy image processing, it is necessary to always return the camera toward a fixed imaging direction at a fixed inspection position. However, for example, when the camera itself or the camera holding bracket is displaced due to heat or the like during the cutting process, even if the camera is returned after the cutting process, the imaging direction may be displaced from the inspection position. In such a case, an error occurs between the image of the chip imaged before the cutting process and the image of the chip imaged after the cutting process, and the image processing accuracy decreases. Since this error increases geometrically as the imaging distance between the camera and the chip increases, the image processing accuracy at that time is greatly reduced. In addition, the cutting powder or cutting agent generated by cutting is scattered in the machining zone of the machine tool, but when the cutting powder or cutting agent adheres to the camera, the chip image taken after the cutting process is not clear. The image processing accuracy is reduced.

  An object of the present invention is to provide a cutting tool inspection system capable of always accurately processing a cutting tool image captured by a camera and accurately inspecting the cutting tool.

In order to solve the above-described problem, the structural feature of the invention according to claim 1 is that in the cutting tool inspection system for imaging a cutting tool provided in a machine tool and inspecting the state of the cutting tool, the cutting tool is provided. A reference mark device having a reference mark serving as a reference for obtaining the contour position of the reference mark, and a camera device having a camera for imaging the reference mark and the cutting tool, the reference being positioned at an inspection position close to the cutting tool The mark and the cutting tool are imaged by the camera in the same field of view, and the state of the cutting tool is inspected. Further, at least one of a mark cleaning unit for cleaning the reference mark and a camera cleaning unit for cleaning the camera is provided. Further, the mark cleaning means and the camera cleaning means are arranged in an isolation zone isolated from a processing zone for processing the workpiece by the cutting tool.

According to a second aspect of the present invention, in the first aspect, the mark cleaning unit and the camera cleaning unit are disposed at an entrance / exit of an isolation zone of the reference mark device and the camera device. And a cleaning operation is automatically performed by the movement of the camera device.

The structural feature of the invention according to claim 3 is a reference for obtaining the contour position of the cutting tool in a cutting tool inspection system that inspects the state of the cutting tool by imaging the cutting tool provided in the machine tool. A reference mark device having a reference mark; and a camera device having a camera for imaging the reference mark and the cutting tool, wherein the camera detects the reference mark and the cutting tool positioned at an inspection position close to the cutting tool. Is to inspect the state of the cutting tool by imaging in the same field of view. In addition, a plurality of the reference marks are arranged around the field of view of the camera, and a vector of a difference between the center of gravity of all the reference marks and the center of gravity of a predetermined part of the reference marks is obtained in advance, When all of the fiducial marks cannot be recognized because the cutting tool is in the field of view of the camera, the part of the fiducial marks is selected from the recognizable fiducial marks, the center of gravity is obtained, and the corresponding The center of gravity of all the reference marks is obtained from the difference vector, or a correction vector from each of the reference marks to the center of gravity of all the reference marks is obtained in advance, and the cutting tool is present in the field of view of the camera. Therefore, when all the reference marks cannot be recognized, all the centroids are obtained and averaged by the correction vector corresponding to the recognizable reference marks. It is to find the center of gravity of the serial reference mark.

According to the first aspect of the present invention, since the mark cleaning means and the camera cleaning means are arranged in the isolation zone isolated from the processing zone for processing the workpiece by the cutting tool , the mark cleaning means and the camera cleaning means are generated by cutting in the processing zone. Thus, it is possible to prevent the cutting powder, the cutting agent, and the like scattered from adhering to the mark cleaning means and the camera cleaning means. Thereby, the reference mark and the camera can be kept clean at all times.

According to the second aspect of the present invention, the mark cleaning means and the camera cleaning means are arranged at the entrance / exit of the reference mark device and the camera device so that the cleaning operation can be automatically performed by the movement of the reference mark device and the camera device. Therefore, an increase in apparatus cost can be suppressed as compared with the case where the mark cleaning means and the camera cleaning means that operate independently are provided.

According to the invention of claim 3, a plurality of reference marks are arranged around the camera field of view and can be recognized when all the reference marks cannot be recognized because the cutting tool is in the camera field of view. The center of gravity of all the reference marks is obtained using only the reference marks. Thereby, since the contour position of the cutting tool can always be obtained with high accuracy, the cutting tool can be accurately inspected to improve the cutting accuracy of the cutting tool.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
As shown in FIGS. 1 and 2, in the turret lathe 1, a headstock 10 fixed so that its axis is parallel to the Z-axis direction (horizontal direction), a direction parallel to the Z-axis direction, and the Z-axis A turret device 20 that is movable in a direction parallel to the X-axis direction that is orthogonal to the direction and tilted rearward by 60 degrees with respect to the vertical direction is opposed to the turret device 20. 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 grips the workpiece W is attached to the tip of the main shaft 11 on the turret device 20 side. The headstock 10 and the spindle drive motor having such a configuration are fixed on the bed 13.

  The turret device 20 is provided with a turret tool post 21 so that it can be rotated and indexed about an axis parallel to the Z-axis direction. On the turret tool post 21, a plurality of cutting tools T are attached at equal angular intervals on the circumference. The turret device 20 having such a configuration is attached to the X-axis slide 22. The X-axis slide 22 is mounted on the Z-axis slide 23 so as to be movable in a direction parallel to the X-axis direction, and is moved by an unillustrated X-axis servo motor via an unillustrated ball screw mechanism. ing. The Z-axis slide 23 is mounted on the bed 24 so as to be movable in a direction parallel to the Z-axis direction, and is moved by a Z-axis servo motor (not shown) via a ball screw mechanism (not shown). .

  A cover 2 that covers the headstock 10 and the turret device 20 is provided in the turret lathe 1, and a partition 2 c that partitions the headstock 10 side and the turret device 20 side is provided in the cover 2. The turret device 20 moves with respect to the headstock 10 fixedly arranged, and the cutting tool T on the turret tool post 21 cuts the outer periphery and the end face of the workpiece W held by the chuck 12. Thus, the partition wall 2c is provided so that cutting powder, cutting fluid, and the like that are scattered will not adhere to the headstock 10 or the like. That is, the headstock 10 side partitioned by the partition wall 2 c is the isolation zone 3, and the turret device 20 side is the processing zone 4. The main shaft 11 protrudes from the hole provided in the partition wall 2 c to the machining zone 4 side, and a chuck 12 is attached to the tip of the main shaft 11.

  Further, in the turret lathe 1, there is provided a cutting tool inspection system 30 that images, for example, a tip of the cutting tool T (a cutting edge in the case of a cutting tool that is not a tip such as a high speed steel) and inspects the state of the tip. This cutting tool inspection system 30 includes a reference mark rod (reference mark device) 40 having a reference mark serving as a reference for obtaining the contour position of the chip, and a camera rod (camera device) 50 having a camera for imaging the reference mark and the chip. And. The cutting tool inspection system 30 is attached to the headstock 10 so as to be movable in a direction parallel to the Z-axis direction. Note that the cutting tool inspection system 30 may be attached to the bed 13 in addition to the headstock 10 as long as it is a member to which a workpiece is attached.

  The cutting tool inspection system 30 will be described in more detail. As shown in FIG. 3, the reference mark rod 40 is located on the lower side, the camera rod 50 is located on the upper side, and the longitudinal directions of the reference mark rod 40 and the camera rod 50 are The reference mark part 40a and the camera part 50a are arranged so as to face the right direction in parallel with the Z-axis direction. The opposing side surfaces of the reference mark rod 40 and the camera rod 50 on the left end side are connected by a connecting member 32, and the left end portion of the reference mark rod 40 is attached to the head stock 10 via the drive device 33.

  The drive device 33 includes a hydraulic cylinder, a pneumatic cylinder, or the like, and the reference mark rod 40 and the camera rod 50 are movable by the drive device 33 in a direction parallel to the Z-axis direction. During the cutting process, the shutters 31a and 31b of the entrances 2a and 2b provided in the partition wall 2c are closed, and the reference mark rod 40 and the camera rod 50 are located at the retracted position in the isolation zone 3, and during the inspection, the shutter 31a. 31b is opened, and the reference mark portion 40a and the camera portion 50a protrude from the entrances 2a and 2b toward the processing zone 4 and are located at the inspection position. The shutters 31a and 31b can prevent the cutting powder or cutting fluid generated and scattered during the cutting process from entering the isolation zone 3 from the entrances 2a and 2b.

  As shown in FIG. 3, the reference mark rod 40 is formed in a rounded rectangular parallelepiped shape without protrusions. Thereby, the entrance / exit between the isolation zone 3 and the process zone 4 can be performed smoothly. In particular, by eliminating the catch when returning from the processing zone 4 to the isolation zone 3, it is possible to prevent the cutting powder or the cutting fluid from entering the isolation zone 3. A transparent glass gauge 41 is embedded in the upper side surface of the reference mark portion 40a of the reference mark rod 40. The reference mark is imprinted with ink by printing or etching.

  A light emitting body 42 is disposed on the lower surface side of the gauge 41, and a protective body 43 made of transparent glass is disposed on the upper surface of the gauge 41. The illuminant 42 is lit only during imaging in order to reduce the thermal distortion of the gauge 41 due to heat generation. Note that the wiring of the light emitter 42 is passed through the reference mark rod 40. The protector 43 is fitted with a reference by fitting or the like so that the surface of the protector 43 is flush with the surface of the reference mark rod 40 and can be easily replaced when the light transmittance is reduced due to scratches or the like. It is attached to the mark rod 40. The boundary between the protective body 43 and the reference mark rod 40 is sealed by a sealing member, and the inside of the reference mark rod 40 is kept watertight.

  Further, as shown in FIG. 4, gas, for example, air is sprayed toward the surface of the protective body 43 on both sides of the protective body 43 of the reference mark rod 40, and cutting powder adhered to the surface of the protective body 43 An air injection nozzle (gas injection means) 44 is provided for cleaning by blowing away cutting fluid or the like. The air injection nozzle 44 is formed in a plate shape and is screwed to both sides of the protective body 43 of the reference mark rod 40, and also serves as a presser for the protective body 43. Three air jet outlets 44 a communicating with an air flow passage 44 b formed inside the air jet nozzle 44 are drilled side by side on opposite surfaces of the air jet nozzles 44 arranged on both sides of the protective body 43. The air flow passage 44b is connected to an unillustrated air pipe passing through the inside of the reference mark rod 40 from an unillustrated air pump arranged on the headstock 10 side.

  The formation surface of the air injection port 44a of the air injection nozzle 44 disposed on the lower side is formed with an inclined surface of 30 degrees. This is because the reference mark rod 40 is inclined backward by 60 degrees with respect to the vertical direction. This is because it is easy to allow cutting powder, cutting fluid, and the like to fall from the formation surface of the air ejection port 44a. That is, if the formation surface of the air outlet 44a is formed as a vertical surface, cutting powder or cutting fluid may accumulate on the formation surface. It is to be noted that an air jet port for injecting air in a direction perpendicular to the formation surface is further formed on the formation surface of the air jet port 44a, or that the air jet port 44a is also jetted in a direction perpendicular to the formation surface. By forming in this way, air can also be sprayed onto the tip of the cutting tool positioned above at the time of inspection, and the cutting powder or cutting fluid adhering to the surface of the tip can be blown away for cleaning.

  The camera rod 50 is also formed in a rounded rectangular parallelepiped shape having no protrusions as shown in FIG. Thereby, the entrance / exit between the isolation zone 3 and the process zone 4 can be performed smoothly. In particular, by eliminating the catch when returning from the processing zone 4 to the isolation zone 3, it is possible to prevent the cutting powder or the cutting fluid from entering the isolation zone 3. A transparent glass protective body 51 is embedded in the lower surface of the camera portion 50a of the camera rod 50. Inside the camera unit 50a and above the protective body 51, a reflection mirror 52 is disposed to be inclined 45 degrees counterclockwise with respect to the X-axis direction, and to the left of the reflection mirror 52 inside the camera unit 50a. A camera 54 such as a CCD having a condensing lens 53 is arranged. The protective body 51 is inserted into the camera rod 50 so that the surface of the protective body 51 is flush with the surface of the camera rod 50 and can be easily replaced when the light transmittance is reduced due to scratches or the like. 50 is attached. The boundary between the protective body 51 and the camera rod 50 is sealed by a sealing member, and the inside of the camera rod 50 is kept watertight.

  Further, as shown in FIG. 5, gas, for example, air is sprayed toward the surface of the protective body 51 on both sides of the protective body 51 of the camera rod 50, and cutting powder or cutting adhered to the surface of the protective body 51. An air injection nozzle (gas injection means) 55 is provided for cleaning by blowing off liquid or the like. The air injection nozzle 55 is formed in a plate shape and is screwed to both sides of the protection body 51 of the camera rod 50, and also serves as a presser for the protection body 51. Three air jet outlets 55 a communicating with an air flow passage 55 b formed inside the air jet nozzle 55 are punched side by side on opposite surfaces of the air jet nozzle 55 arranged on both sides of the protective body 51. The air flow passage 55b is connected to an unillustrated air pipe passing through the inside of the camera rod 50 from the above-described air pump disposed on the headstock 10 side. Only one of the air injection nozzles 44 and 55 may be provided.

  As shown in FIG. 3, the surface of the protective body 43 of the reference mark rod 40 and the surface of the protective body 51 of the camera rod 50 are particularly cleaned on the wall surface near the entrances 2a and 2b of the partition wall 2c and on the isolation zone 3 side. A reference mark brush (mark cleaning means) 61 and a camera brush (camera cleaning means) 62, and a water jet nozzle (fluid jet means for spraying water, for example, water containing water or air when cleaning is performed by the brushes 61, 62) ) 63 is fixedly arranged. The water jet nozzle 63 is formed in a rod shape and has water jet ports 63a and 63b which are communicated with a water flow passage 63c formed therein and are drilled at both ends. The water flow passage 63c is connected to a pipe extending from a pump (not shown) disposed on the headstock 10 side. The reference mark brush 61 and the camera brush 62 are attached in the vicinity of the water jet outlets 63a and 63b of the water jet nozzle 63 so that the hair tips are in sliding contact with the upper side surface of the reference mark rod 40 and the lower side surface of the camera rod 50. Therefore, each time the reference mark rod 40 and the camera rod 50 move between the isolation zone 3 and the processing zone 4, the surface of the protective body 43 and the surface of the protective body 51 can be automatically cleaned. Note that only one of the reference mark brush 61 and the camera brush 62 may be provided.

  When inspecting the tip of the cutting tool by the cutting tool inspection system 30 having such a configuration, the shutters 31a and 31b of the entrances 2a and 2b of the partition wall 2c are opened, and the reference mark portion 40a of the reference mark rod 40 and the camera rod 50 are opened. The camera unit 50a protrudes from the entrances 2a and 2b toward the processing zone 4 and is located at a predetermined inspection position. Subsequently, the air injection nozzles 44 and 55 of the reference mark rod 40 and the camera rod 50 inject air toward the surfaces of the protective bodies 51 and 43 to clean the surfaces of the protective bodies 43 and 51. Then, the turret device 20 moves so that the tip of the cutting tool is located at a predetermined inspection position above the gauge 41 of the reference mark rod 40. At this time, the distance from the reference mark portion 40a (gauge 41) to the inspection position of the chip is set to be extremely smaller than the distance from the reference mark portion 40a (gauge 41) to the camera portion 50a (camera 54). Therefore, even if the camera unit 50a (camera 54) is displaced in the horizontal direction (Z-axis direction), the displacement can be ignored in the inspection. Since the preparation for the inspection is completed as described above, the inspection is started.

  The light emitted from the light emitter 42 of the reference mark portion 40a is transmitted through the gauge 41 and the protective body 43 and irradiated to the camera portion 50a, and the light transmitted through the protective body 51 of the camera portion 50a is 90 degrees by the reflection mirror 52. The light is reflected and condensed by the lens 53 and reaches the camera 54. Thereby, since the chip | tip of a cutting tool can be imaged with the same visual field with the reference mark marked on the gauge 41, the state of a chip | tip is test | inspected by processing the said image with a computer. Note that the image from the reflection mirror 52 is reversed left and right, but is restored to the original state by software processing.

  After completion of the inspection, the turret device 20 moves so that the tip of the cutting tool is located at the cutting start position from a predetermined inspection position above the gauge 41 of the reference mark rod 40. Then, the reference mark portion 40a of the reference mark rod 40 and the camera portion 50a of the camera rod 50 are retracted from the entrances 2a and 2b to the isolation zone 3 side and positioned at a predetermined retraction position, and the shutters 31a of the entrances 2a and 2b of the partition wall 2c. , 31b are closed. Note that the air injection nozzles 44 and 55 of the reference mark rod 40 and the camera rod 50 inject air toward the surfaces of the protective bodies 51 and 43 to clean the surfaces of the protective bodies 43 and 51 before the retreat position moving operation. Anyway.

  Here, when the cutting tool tip is inspected by image processing, the cutting tool tip enters the camera field of view from various angles. For example, when a reference mark is formed at the center of the field of view, the reference mark is It may be hidden by the chip so that image processing is impossible, or the chip image may not be captured sufficiently. For this reason, it is necessary to capture the image of the reference mark and the image of the chip separately, and the inspection takes a long time.

  As shown in FIG. 6, the gauge 41 provided in the reference mark portion 40a of the reference mark rod 40 of the present embodiment is formed in a quadrangular shape with transparent glass and includes 28 reference marks M along the inner periphery. Is imprinted with ink by printing or etching. A square area surrounded by a dashed line in the figure formed inside the reference mark M is a total measurement area AA used when the chip of the cutting tool is entirely inspected, and is further formed inside the area. A rectangular area surrounded by a two-dot chain line in the figure is a cutting edge measurement area AC used when inspecting the tip of a cutting tool tip. Since a plurality of reference marks M formed on such a gauge 41 are taken into the field of view of the camera 54, even if the tip of the cutting tool enters the field of view of the camera 54 from various angles, the image of the reference mark M and the chip Images can be captured at once and image processing can be performed by the first method or the second method described below.

  In the first method, first, 28 reference marks M are grouped. For example, seven reference marks M formed along the left side of the gauge 41 and eight reference marks M formed along the lower side of the gauge 41 (excluded because one corner overlaps). Is the first group. Seven reference marks M formed along the left side of the gauge 41 and eight reference marks M formed along the upper side of the gauge 41 (excluded because one corner overlaps) There are two groups. Seven reference marks M formed along the right side of the gauge 41 and eight reference marks M formed along the upper side of the gauge 41 (excluded because one corner overlaps) There are 3 groups. Seven reference marks M formed along the right side of the gauge 41 and eight reference marks M formed along the lower side of the gauge 41 (excluded because one corner overlaps) There are 4 groups. Then, the center of gravity G of all the 28 reference marks M is obtained, the centers of gravity G1 to G4 of the reference marks M of each group are obtained, and vectors V1 to V4 of differences between the center of gravity G and the centers of gravity G1 to G4 are obtained. Store in memory.

  Next, when the tip enters the field of view of the camera 54 in the inspection of the tip of the cutting tool and, for example, the third group reference mark M cannot be recognized, the first group reference mark M can be recognized. Therefore, the center of gravity g1 of the reference mark M of the first group at that time is obtained. Then, the difference vector V1 corresponding to the reference mark M of the first group is read from the memory of the computer, and corresponds to the center of gravity g1 of the reference mark M of the first group obtained previously and the read reference mark M of the first group. The center of gravity g of all the reference marks M is obtained from the difference vector V1. Then, the center of gravity g is used to obtain the chip contour position (edge and nose R), and the chip is inspected for breakage or wear.

In the second method, first, correction vectors v1 to v28 from the 28 reference marks M (M1 to M28) to the centroids G of all 28 reference marks M are obtained and stored in the memory of the computer. Keep it. Next, when the chip enters the field of view of the camera 54 in the inspection of the chip of the cutting tool and, for example, the reference marks M1 to M8 cannot be recognized, correction corresponding to the remaining recognizable reference marks M9 to M28 is performed. The centroids g9 to g28 are obtained from the vectors v9 to v28, and the average value thereof is obtained. Then, the obtained average value is set as the center of gravity g0 of all the reference marks M, and the center of gravity g0 is used to obtain the chip contour position (edge and nose R) to inspect chip breakage, wear, and the like.
According to each of the above methods, since the relationship between the reference mark M and the tip of the cutting tool does not change, when the reference mark portion 40a of the reference mark rod 40 stops at a predetermined inspection position, the stop position is displaced. However, no deviation occurs in the contour position of the cutting tool tip obtained from the absolute position of the center of gravity g or g0 of the reference mark M at that time. Therefore, by comparing the contour position of the tip of the cutting tool before cutting with the contour position of the tip of the cutting tool after cutting, it is possible to inspect chip breakage, wear, and the like with high accuracy.

  The edge of the chip can be obtained using a seek line. 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. As shown in FIG. 7A, the edge of the chip C is obtained by setting a plurality of seek lines La. The edges of the chip C before and after use are obtained and pattern matching is performed. If the positions of the edges differ by more than a set value, it is determined that the chip C is broken (abnormal in case of a component tooth tip).

  The nose R of the chip can also be obtained using a seek line. First, as shown in FIG. 7B, 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. 7C, 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. 7D, 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. Then, the larger of the distance Rz and the distance Rx is set as the nose R. When the nose R of the chip C after use is higher than the set value than the nose R of the chip C before use, it is determined that the chip C is worn.

  Although a plurality of reference marks M are formed on the gauge 41, for example, a triple concentric reference mark m may be formed at the center of the gauge 41 as shown in FIG. As described above, since the reference mark m is formed as large as possible, it is possible to reduce the situation where the image processing is impossible due to being hidden by the chip. Further, since the gaps between the concentric circles are formed, it is possible to reduce the obstruction of the camera view. Further, although the image of the reference mark M and the image of the chip C are captured at once, the image of the reference mark M or the reference mark m and the image of the chip C may be captured separately.

  As described above, according to the cutting tool inspection system 30 of the present embodiment, the reference mark M and the chip C positioned at the inspection position close to the chip C are imaged by the camera 54 in the same field of view, and the state of the chip C The image processing of the chip C is performed with reference to the reference mark M. Since the reference mark rod 40 is attached to the headstock 10 to which the workpiece is attached, for example, the reference mark M is not directly affected even if the camera 54 is displaced from the inspection position or the imaging direction is inclined due to the influence of heat or the like. Therefore, it is not necessary to adjust the position and direction of the camera with high accuracy as in the past, and the cutting tool can be accurately inspected while maintaining the image processing accuracy at a high level at all times. The cutting accuracy by the can be improved. Further, when the X-axis and Z-axis slides 22 and 23 to which the cutting tool is attached other than the headstock 10 are displaced, the displacement can be corrected and fed back based on the image processing result. Therefore, the cutting tool can be inspected more accurately while maintaining the image processing accuracy at a high level at all times, and the cutting accuracy by the cutting tool can be further improved. The inspection timing is corrected by image processing every time the cutting tool tip (cutting tool) is replaced (set-up), or is corrected by image processing every time the cutting tool tip (cutting tool) is indexed by a change in process. .

  In the above-described embodiment, the case where the cutting tool inspection system 30 is applied to a lathe having a configuration in which the X-axis direction is inclined backward by 60 degrees with respect to the vertical direction has been described, but the X-axis direction is directed to the vertical direction. A lathe having a configuration can be similarly applied. Further, it can be applied to, for example, a milling machine other than a lathe. In this case, the cutting tool inspection system 30 is attached so as to be movable in the vertical direction on a work slide or jig body to which a workpiece is attached. Then, the partition wall is provided horizontally, the lower part of the partition wall is set as an isolation zone, and the upper part of the partition wall is set as a processing zone.

  In the above-described embodiment, a general lens is used as the lens 53 provided in the camera rod 50, but a telecentric lens may be used. According to this telecentric lens, the influence of the distance (X-axis direction) from the reference mark portion 40a (gauge 41) to the camera portion 50a (camera 54) can be eliminated, and the horizontal displacement of the camera portion 50a (camera 54) can be eliminated. The influence of (Z-axis direction) can be eliminated.

  In the above-described embodiment, the brush for cleaning the surface of the protective body 43 of the reference mark rod 40 and the surface of the protective body 51 of the camera rod 50 is provided. However, a brush formed in a scraper shape is provided. May be. The reference mark brush 61 and the camera brush 62 are arranged so as to clean the side surface of the reference mark rod 40 on the protective body 43 side and the side surface of the camera rod 50 on the protective body 51 side. You may arrange | position, for example in four places so that all the side surfaces and all the side surfaces of the camera rod 50 can be cleaned.

  Further, although the reference mark brush 61, the camera brush 62, and the water jet nozzle 63 are fixedly arranged on the partition wall 2c, a configuration as shown in FIG. 9 may be used. That is, the reference mark water jet nozzle 71 includes a reference mark brush 72 at the right end, the left end is rotatably attached to the headstock 10, and a spring 73 that biases toward the reference mark rod 40 side at a substantially central portion. Installed configuration. The water jet nozzle for camera 74 has a camera brush 75 at the right end, the left end is rotatably attached to the headstock 10, and a spring 76 that is biased toward the camera rod 50 is attached to the substantially central portion. To do. Even with such a configuration, the surface of the protective body 43 and the surface of the protective body 51 are automatically cleaned each time the reference mark rod 40 and the camera rod 50 move between the isolation zone 3 and the processing zone 4. Can do.

  In the above-described embodiment, the reference mark rod 40 and the camera rod 50 are arranged side by side in the X-axis direction. However, by further arranging a pair of the reference mark rod 40 and the camera rod 50 in the X-axis direction, It becomes possible to inspect the tip of the cutting tool in three dimensions. Further, in the case of a lathe equipped with a turret device that can also move in the Y-axis direction orthogonal to the X-axis direction and the Z-axis direction, the turret device 20 is rotated 90 degrees after inspecting one direction of the cutting tool tip. After or simultaneously with the movement in the Y-axis direction, it is possible to inspect in three dimensions by inspecting the cutting tool tip in a direction rotated 90 degrees from the previous one direction. In the case of a milling machine, the tool can be rotated, so that it can be inspected in three dimensions.

It is a front view which shows the turret lathe provided with the cutting tool inspection system which concerns on embodiment of this invention. (A) And (B) is the front view and side view which show the periphery of a cutting tool inspection system. It is a front view of a cutting tool inspection system. It is a perspective view which shows the reference | standard mark rod of a cutting tool inspection system. It is a perspective view which shows the camera rod of a cutting tool inspection system. It is a figure which shows the gauge in which the reference mark of the reference mark rod was formed. (A) is a figure which shows a mode that the edge of the chip | tip for a cutting tool test | inspection is calculated | required, (B)-(D) is a figure which shows a mode that the nose R of a chip | tip for a test | inspection of a cutting tool is calculated | required. It is a figure which shows another form of the gauge in which the reference mark of the reference mark rod was formed. It is a figure which shows another form of the brush for reference marks, the brush for cameras, and a water injection nozzle.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Main body, 2 ... Partition, 3 ... Isolation zone, 4 ... Machining zone, 10 ... Headstock, 20 ... Turret device, 30 ... Cutting tool inspection system, 31a, 31b ... Shutter, 33 ... Drive device, 40 ... Reference mark Rod, 40a ... reference mark part, 41 ... gauge, 42 ... light emitter, 43 ... protector, 44 ... air injection nozzle, 50 ... camera rod, 50a ... camera part, 51 ... protector, 52 ... reflecting mirror, 53 ... Lens, 54 ... Camera, 55 ... Air injection nozzle, 61, 72 ... Reference mark brush, 62, 75 ... Camera brush, 63 ... Water injection nozzle, 71 ... Reference mark water injection nozzle, 74 ... Camera water injection nozzle, M, m ... reference mark, C ... chip.

Claims (3)

In a cutting tool inspection system that images a cutting tool provided in a machine tool and inspects the state of the cutting tool,
A reference mark device having a reference mark as a reference for obtaining the contour position of the cutting tool;
A camera device having a camera for imaging the reference mark and the cutting tool;
At least one of a mark cleaning means for cleaning the reference mark and a camera cleaning means for cleaning the camera, and the reference mark and the cutting tool positioned at an inspection position close to the cutting tool in the same field of view by the camera. Inspect the state of the cutting tool by imaging,
The mark cleaning means and said camera cleaning means, a cutting tool inspection system, characterized in that the said cutting engineering tool is positioned within isolation zone that is isolated from the machining zone for machining the workpiece.
2. The mark cleaning unit and the camera cleaning unit according to claim 1, wherein the mark cleaning unit and the camera cleaning unit are arranged at an entrance / exit of an isolation zone of the reference mark device and the camera device, and automatically perform a cleaning operation by movement of the reference mark device and the camera device. Cutting tool inspection system characterized by In a cutting tool inspection system that images a cutting tool provided in a machine tool and inspects the state of the cutting tool,
A reference mark device having a reference mark as a reference for obtaining the contour position of the cutting tool;
A camera device having a camera for imaging the reference mark and the cutting tool;
Inspecting the state of the cutting tool by imaging the reference mark and the cutting tool positioned at an inspection position close to the cutting tool with the camera in the same field of view ,
A plurality of the reference marks are arranged around the camera field of view,
A vector of a difference between the center of gravity of all the reference marks and the center of gravity of a predetermined part of the reference marks is obtained in advance, and all the reference marks are recognized because the cutting tool is in the field of view of the camera. If not, select the part of the reference marks that can be recognized to determine the center of gravity, and determine the center of gravity of all the reference marks by the corresponding difference vector,
Alternatively, a correction vector from each of the reference marks to the center of gravity of all the reference marks is obtained in advance, and the recognition is performed when all the reference marks cannot be recognized because the cutting tool is in the field of view of the camera. Determining the centroid of all the reference marks by determining and averaging each centroid with the correction vector corresponding to the possible reference marks;
Cutting tool inspection system characterized by

Images