JP6610367B2 - Inspection apparatus and inspection method for inspection object - Google Patents

Description

  The technology disclosed in the present application relates to an inspection apparatus and an inspection method for an object to be inspected.

  As a method for inspecting the appearance of a cylindrical or columnar object to be inspected, manual visual inspection is assumed. However, in the manual visual inspection, the labor cost increases and the manufacturing cost increases, and there is a possibility that the inspection accuracy may deteriorate due to oversight of defects.

  Therefore, in order to realize cost reduction by labor saving and improvement of inspection accuracy by preventing oversight of defects, automation of appearance inspection is considered. As an automatic inspection apparatus that automatically performs this appearance inspection, for example, there is an apparatus that includes a rotation drive mechanism that rotates an object to be inspected around an axis, and a camera that images the appearance of the object to be inspected.

Japanese Patent Laid-Open No. 11-51620 Japanese Patent Laid-Open No. 11-201742 JP 2007-17194 A

  However, when imaging the appearance of the inspection object while rotating the inspection object around the axis, if the axis of the inspection object is inclined with respect to the normal position, the appearance of the inspection object There is a possibility that the normal position cannot be imaged, and there is a possibility that the inspection accuracy cannot be secured.

  Then, the technique which this application discloses aims at ensuring the test | inspection precision in automating the external appearance test | inspection of a to-be-inspected object as one side surface.

  In order to achieve the above object, according to one aspect of the technology disclosed in the present application, an inspection object inspection apparatus including a rotation drive mechanism, a camera, a calculation unit, an extraction unit, and a synthesis unit is provided. Is done. The rotation drive mechanism rotates a cylindrical or columnar object to be inspected around the axis. The camera images the outer peripheral surface of the inspection target object and the pair of axial end surfaces on both sides at the same time a plurality of times per rotation of the inspection target object, and a plurality of outer peripheral surface images and a plurality of pairs of axial end surface images. And get. The calculation unit calculates the inclination of the axis of the inspection object at the time of each image pickup by the camera based on the position of the pair of axial end face images obtained at the time of each image pickup. The extraction unit extracts a part in the circumferential direction of the outer peripheral surface image for each of the outer peripheral surface images obtained simultaneously with the pair of axial end surface images at the time of each imaging based on the inclination of the axis of the inspection target object. Thus, a plurality of partial images are generated. The synthesizing unit synthesizes the plurality of partial images to generate a synthesized image corresponding to the entire circumference of the outer circumferential surface of the inspection object.

  According to one aspect of the technology disclosed in the present application, it is possible to ensure inspection accuracy when automating the appearance inspection of an object to be inspected.

It is a side view which shows an example of the inspection apparatus of a to-be-inspected object. It is a top view of the inspection apparatus shown by FIG. It is a block diagram which shows an example of a functional structure of the inspection apparatus of a to-be-inspected target object. It is a block diagram which shows an example of the hardware constitutions of the inspection apparatus of a to-be-inspected object. It is a flowchart which shows an example of the flow of the process in the test | inspection method of a to-be-inspected target object. 6 is a flowchart showing a continuation of the processing flow shown in FIG. 5. It is a figure explaining an example from the rotation control process which rotates a to-be-inspected object to the imaging control process to image the external appearance of a to-be-inspected object. It is a two-view figure which shows the example which the axis line of to-be-inspected object inclines with respect to the Y-axis on XY plane. Extraction processing for generating a partial image by extracting a part in the circumferential direction of the outer peripheral surface image from the calculation processing for calculating the inclination of the axis of the object to be inspected and the position in the Y-axis direction for the example shown in FIG. It is a figure explaining an example until. It is a two-view figure which shows the example which the axis line of to-be-inspected object inclines with respect to the Y-axis on a YZ plane. Extraction processing for generating a partial image by extracting a part of the outer peripheral surface image in the circumferential direction from the calculation processing for calculating the inclination of the axis of the object to be inspected and the position in the Y-axis direction for the example shown in FIG. It is a figure explaining an example until. It is a figure explaining an example of the correction process which correct | amends the partial image obtained by the trapezoid shape shown by FIG. 11 to rectangular shape. It is a figure explaining an example of the synthetic | combination process which synthesize | combines a some partial image and produces | generates a synthesized image. It is a figure explaining an example of the rearrangement process which rearranges the some partial image which forms a synthesized image, and produces | generates a test | inspection image. It is a figure explaining an example from the determination process which determines the presence or absence of the defect in the outer peripheral surface of a to-be-inspected object based on a difference image from the difference process which produces | generates the difference image which made the inspection image the difference from a quality product image.

  Hereinafter, an embodiment of the technology disclosed in the present application will be described.

  An inspection apparatus 10 according to the present embodiment illustrated in FIG. 1 is an example of an “inspection apparatus for an inspection target” in the technology disclosed in the present application, and performs an appearance inspection of the inspection target 12. In the present embodiment, an example will be described in which a cylindrical dry battery is the inspection object 12. When the inspection object 12 is a dry battery, the outer peripheral surface 12A of the inspection object 12 is in a state where, for example, a label is attached or printed. The inspection apparatus 10 that performs an appearance inspection of the inspection object 12 includes a rotation drive mechanism 14, a pair of mirrors 16, a camera 18, and a control unit 20.

  The rotation drive mechanism 14 rotates the inspection object 12 around the axis. As shown in FIG. 2, the rotational drive mechanism 14 includes a motor 22 and a pair of rollers 24. The output shaft of the motor 22 is connected to a pair of rollers 24 via a power transmission mechanism. The XY plane shown in FIG. 2 is orthogonal to the optical axis 18A of the camera 18 shown in FIG. 1, and the pair of rollers 24 is centered on a rotation axis extending along the Y axis of the XY plane. It is rotatably supported.

  In addition, the pair of rollers 24 are arranged apart from each other, and the separation distance between the pair of rollers 24 is set to be less than the diameter of the object 12 to be inspected. In the recess between the pair of rollers 24, the inspection object 12 is disposed. When the motor 22 is operated, the pair of rollers 24 rotate in synchronization with the same direction, and the inspection target 12 rotates around the axis with the direction along the Y axis as the axial direction of the inspection target 12. Note that one of the pair of rollers 24 may be driven and the other roller 24 may be driven.

  The pair of mirrors 16 are disposed on both sides in the axial direction of the inspection object 12. Each mirror 16 is inclined with respect to the XY plane so as to face the end surface 12B in the axial direction of the inspection object 12 and the camera 18 side. The inclination angle of each mirror 16 is set so that the mirror image of the axial end surface 12B of the inspection object 12 reflected on the pair of mirrors 16 falls within the imaging range of the camera 18.

  The camera 18 is disposed on the opposite side of the pair of rollers 24 with respect to the inspection object 12 and in the center between the pair of mirrors 16. The orientation of the camera 18 is set so that the optical axis 18A of the camera 18 is orthogonal to the XY plane shown in FIG.

  The camera 18 simultaneously captures the outer peripheral surface 12A of the object 12 to be inspected and the mirror images of the pair of axial end surfaces 12B on both sides reflected on the pair of mirrors 16. The camera 18 can image a plurality of times per rotation of the inspection object 12.

  The camera 18 captures the outer peripheral surface 12A of the inspection target object 12 and the mirror image of the pair of axial end surfaces 12B on both sides reflected on the pair of mirrors 16 a plurality of times, so that a plurality of outer peripheral surface images and a plurality of pairs of pairs are captured. An axial end face image is obtained. The outer peripheral image is an image of the outer peripheral surface 12A of the inspection object 12, and the pair of axial end surface images is a mirror image of a pair of axial end surfaces 12B on both sides reflected on the pair of mirrors 16. .

  The control unit 20 is realized by an information processing apparatus such as a personal computer, for example. As shown in FIG. 3, the control unit 20 includes a rotation control unit 32, an imaging control unit 34, a calculation unit 36, an extraction unit 38, a correction unit 40, and a synthesis unit 42 for each functional unit. The rearrangement unit 44, the difference unit 46, and the determination unit 48 are included. The function of each functional unit such as the rotation control unit 32 will be described together with the operation of the control unit 20 described in the inspection method for the inspection target described later.

  More specifically, the control unit 20 having each functional unit such as the rotation control unit 32 described above is realized by a computer 50 shown in FIG. The computer 50 includes a CPU (Central Processing Unit) 52, a memory 54 as a temporary storage area, and a nonvolatile storage unit 56. The computer 50 includes an input / output I / F (interface) 58. The input / output I / F 58 is connected to an input / output device 60 such as a keyboard, a card reader, and a display, and the camera 18 and the motor 22 described above.

  The computer 50 also includes an R / W (Read / Write) unit 64 that controls reading and writing of data with respect to the storage medium 62 and a network I / F 66 connected to a network such as the Internet. The CPU 52, the memory 54, the storage unit 56, the input / output I / F 58, the R / W unit 64, and the network I / F 66 are connected to each other via a bus 68.

  The storage unit 56 is realized by an HDD (Hard Disk Drive), an SSD (solid state drive), a flash memory, or the like. The storage unit 56 is an example of a “storage medium” in the technology disclosed in the present application, and the storage unit 56 stores an inspection program 70 for causing the computer 50 to function as the control unit 20.

  The inspection program 70 is an example of an “inspection target object inspection program” in the technology disclosed in the present application. The inspection program 70 includes a rotation control process 72, an imaging control process 74, a calculation process 76, an extraction process 78, a correction process 80, a synthesis process 82, a rearrangement process 84, a difference process 86, and a determination. Process 88.

  The CPU 52 reads the inspection program 70 from the storage unit 56 and expands it in the memory 54, and sequentially executes the above-described plurality of processes included in the inspection program 70. The CPU 52 executes each of the plurality of processes described above, whereby the rotation control unit 32, the imaging control unit 34, the calculation unit 36, the extraction unit 38, the correction unit 40, the synthesis unit 42, and the rearrangement unit illustrated in FIG. 44, the difference unit 46, and the determination unit 48.

  That is, the CPU 52 operates as the rotation control unit 32 by executing the rotation control process 72, and the CPU 52 operates as the imaging control unit 34 by executing the imaging control process 74. Further, the CPU 52 operates as the calculation unit 36 by executing the calculation process 76, and the CPU 52 operates as the extraction unit 38 by executing the extraction process 78.

  Further, the CPU 52 operates as the correction unit 40 by executing the correction process 80, and the CPU 52 operates as the synthesis unit 42 by executing the synthesis process 82. Further, the CPU 52 operates as the rearrangement unit 44 by executing the rearrangement process 84, and the CPU 52 operates as the difference unit 46 by executing the difference process 86. Further, the CPU 52 operates as the determination unit 48 by executing the determination process 88.

  Each functional unit such as the rotation control unit 32 in the control unit 20 described above is realized by, for example, a semiconductor integrated circuit, more specifically, an ASIC (Application Specific Integrated Circuit), in addition to the realization by the inspection program 70. Is possible.

  Next, an inspection method for an object to be inspected using the inspection apparatus 10 will be described.

  In the inspection object inspection method of the present embodiment, a plurality of processes shown in the steps of FIGS. 5 and 6 are executed by the functional units of the control unit 20. Hereinafter, each of the plurality of processes will be described in detail. The numbers and contents of the steps in the following description will be referred to FIGS. 5 and 6 as appropriate.

(Rotation control processing)
The rotation control process is executed in step S11. In step S <b> 11, as shown in the upper diagram of FIG. 7, the rotation control unit 32 operates the motor 22. When the motor 22 is operated, the pair of rollers 24 rotate in synchronization with the same direction, and the inspection target 12 rotates around the axis with the direction along the Y axis as the axial direction of the inspection target 12.

(Imaging control processing)
The imaging control process is executed in step S12. In step S <b> 12, as shown in the upper diagram of FIG. 7, the imaging control unit 34 operates the camera 18 a plurality of times for one rotation of the inspection object 12. Each time the camera 18 is operated, the outer peripheral surface 12A of the inspection object 12 and the mirror images 16A of the pair of axial end surfaces 12B reflected on the pair of mirrors 16 are simultaneously captured by the camera 18.

  Accordingly, as shown in the lower diagram of FIG. 7, the outer peripheral surface image 92 </ b> A obtained by imaging the outer peripheral surface 12 </ b> A of the inspection object 12 and the mirror image of the pair of axial end surfaces 12 </ b> B on both sides reflected on the pair of mirrors 16. A pair of axial end face images 92B obtained by imaging 16A are obtained. In this imaging control process, a plurality of outer peripheral surface images 92 </ b> A and a plurality of pairs of axial end surface images 92 </ b> B are obtained by imaging a plurality of times per rotation of the inspection object 12. The number of imaging per rotation of the inspection object 12 can be arbitrarily set.

(Calculation process)
The calculation process is executed in steps S13 to S16. In step S13, the calculation unit 36 calculates the displacement of the center of gravity of each of the pair of axial end surface images 92B for the pair of axial end surface images 92B obtained at the time of each imaging.

  Here, the situation where the positional deviation of the center of gravity occurs in the pair of axial end face images 92B is as follows. The first is a case where the axis 12C of the inspection object 12 is inclined with respect to the Y axis on the XY plane, as shown in FIG. The second case is a case where the axis 12C of the inspection target object 12 is inclined with respect to the Y axis on the YZ plane as shown in FIG. On the XY plane, the axis 12C of the inspection target 12 may be inclined with respect to the Y axis, and at the same time, the axis 12C of the inspection target 12 may be inclined with respect to the Y axis on the YZ plane.

  As shown in FIG. 8, when the axis 12C of the inspection object 12 is tilted with respect to the Y axis on the XY plane, as shown in the upper diagram of FIG. The center of gravity 92C of each end face image 92B is displaced in the X-axis direction.

  On the other hand, as shown in FIG. 10, when the axis 12C of the inspection object 12 is inclined with respect to the Y axis on the YZ plane, as shown in the upper diagram of FIG. Each center of gravity 92C of the axial end face image 92B is displaced in the Y-axis direction.

  The inclination of the axis 12 </ b> C of the inspection object 12 is determined by, for example, the movement of the inspection object 12 due to the reaction caused by the seam of the label affixed to the outer peripheral surface 12 </ b> A of the inspection object 12 coming into contact with the roller 24. This is caused by the eccentricity of the roller 24 and the distortion of the inspection object 12. The inclination of the axis 12 </ b> C of the inspection object 12 may vary during the rotation of the inspection object 12.

  In step S13, the calculation unit 36 calculates a positional shift in at least one of the X-axis direction and the Y-axis direction at the center of gravity 92C of each of the pair of axial end face images 92B.

  Subsequently, as shown in the upper diagram of FIG. 9, when there is a displacement of the center of gravity 92C in the X-axis direction, in step S14, the calculation unit 36 performs the calculation on the XY plane at the time of each imaging. The inclination of the axis 12C of the inspection object 12 with respect to the Y axis (see the middle diagram of FIG. 9) is calculated. At this time, the calculation unit 36 calculates the inclination of the axis 12C of the object 12 to be inspected with respect to the Y axis on the XY plane based on the positional deviation of the center of gravity 92C in the X axis direction calculated in step S13. calculate.

  Also, as shown in the upper diagram of FIG. 11, when there is a position shift of the center of gravity 92C in the Y-axis direction, in step S14, the calculation unit 36 displays Y on the YZ plane at the time of each imaging. The inclination of the axis 12C of the inspection object 12 with respect to the axis (see the middle diagram of FIG. 11) is calculated. At this time, the calculation unit 36 calculates the inclination of the axis 12C of the inspection target object 12 with respect to the Y axis on the YZ plane based on the position shift of the center of gravity 92C in the Y axis direction calculated in step S13. calculate.

  In step S15, the calculation unit 36 calculates the positions of the axial end portions 92D of the outer peripheral surface image 92A (see the upper diagram of FIG. 9 and the upper diagram of FIG. 11) obtained at the time of each imaging. In step S16, based on the positions of the axial end portions 92D of the outer peripheral surface image 92A, the position of the inspection target object 12 in the Y-axis direction at each imaging is calculated.

(Extraction process)
The extraction process is executed in steps S17 to S19. In step S17, the extraction unit 38 determines whether or not there is an inclination of the axis 12C of the inspection target object 12 with respect to the Y axis on the YZ plane shown in the middle diagram of FIG.

  Here, when the extraction unit 38 determines that there is no inclination of the axis 12C of the inspection target 12 with respect to the Y axis on the YZ plane, that is, the axis of the inspection target 12 on the YZ plane. If 12C is parallel to the Y axis, the process proceeds to step S18. A case where the axis 12C of the inspection target object 12 is parallel to the Y axis on the YZ plane is shown in the middle diagram of FIG.

  In step S18, the extracting unit 38 determines the inclination of the axis 12C of the inspection object 12 with respect to the Y axis on the XY plane shown in the middle diagram of FIG. 9 and the position of the inspection object 12 in the Y axis direction. Based on the above, a part in the circumferential direction of the outer peripheral surface image 92A shown in the lower diagram of FIG. 9 is extracted. A part of the outer peripheral surface image 92A in the circumferential direction is indicated by a rectangular thick frame portion in the lower diagram of FIG. At this time, the extraction unit 38 sets the axial direction of the outer peripheral surface image 92A as the longitudinal direction of the thick frame portion on the XY plane, and the center in the short direction of the thick frame portion is positioned on the axis line of the outer peripheral surface image 92A. The rectangular thick frame portion to be extracted is extracted as a part in the circumferential direction of the outer peripheral surface image 92A.

  Then, the extraction unit 38 generates a partial image 94 at the time of each imaging from a part in the circumferential direction of the extracted outer peripheral surface image 92A. The partial image 94 is obtained from one end portion in the axial direction to the other end portion of the outer peripheral surface image 92A.

  There is no inclination of the axis 12C of the inspection target 12 with respect to the Y axis on the XY plane. In this case, the extracting unit 38 assumes that the value of the inclination of the axis 12C of the inspection target object 12 with respect to the Y axis on the XY plane is zero, and in the circumferential direction of the outer peripheral surface image 92A in the same manner as described above. Extract a part.

  On the other hand, as shown in the middle diagram of FIG. 11, when there is an inclination of the axis 12 </ b> C of the object 12 to be inspected with respect to the Y axis on the YZ plane, the extraction unit 38 performs Y on the YZ plane. It is determined that there is an inclination of the axis 12C of the inspection object 12 with respect to the axis. Then, the extraction unit 38 proceeds to step S19.

  In step S19, the extracting unit 38 determines the inclination of the axis 12C of the inspection target 12 with respect to the Y axis on the YZ plane shown in the middle diagram of FIG. 11 and the position of the inspection target 12 in the Y axis direction. Based on the above, a part in the circumferential direction of the outer peripheral surface image 92A shown in the lower diagram of FIG. 11 is extracted. A part of the outer peripheral surface image 92A in the circumferential direction is indicated by a trapezoidal thick frame portion in the lower diagram of FIG. At this time, the extraction unit 38 sets the axial direction of the outer peripheral surface image 92A on the XY plane to the height direction of the thick frame portion, and the center in the horizontal width direction of the thick frame portion is positioned on the axial line of the outer peripheral surface image 92A. The trapezoidal thick frame portion to be extracted is extracted as a part in the circumferential direction of the outer peripheral surface image 92A.

  Then, the extraction unit 38 generates a partial image 94 at the time of each imaging from a part in the circumferential direction of the extracted outer peripheral surface image 92A. The partial image 94 is obtained from one end portion in the axial direction to the other end portion of the outer peripheral surface image 92A.

  In addition, the axis 12C of the inspection target object 12 may be inclined with respect to the Y axis on the XY plane, and at the same time, the axis 12C of the inspection target object 12 may be inclined with respect to the Y axis on the YZ plane. . In this case, the inclination of the axis 12C of the inspection object 12 with respect to the Y axis on the XY plane, the inclination of the axis 12C of the inspection object 12 with respect to the Y axis on the YZ plane, Based on the position of the inspection object 12 in the Y-axis direction, a part in the circumferential direction of the outer circumferential surface image 92A is extracted.

(Correction process)
The correction process is executed in step S20. In step S20, as shown in FIG. 12, the correction unit 40 obtains a trapezoidal partial image 94 resulting from the inclination of the axis 12C of the inspection object 12 with respect to the Y axis on the YZ plane. Correct the rectangle.

  At this time, the correction unit 40 converts the trapezoidal partial image 94 into a rectangular shape based on the inclination of the axis 12C of the inspection target 12 with respect to the Y axis on the YZ plane shown in the middle diagram of FIG. to correct. In other words, the correction unit 40 has obtained the trapezoidal partial image 94 in a rectangular shape that would have been obtained if the axis 12C of the inspection object 12 was not inclined with respect to the Y axis on the YZ plane. To correct.

(Synthesis process)
The synthesizing process is executed in steps S21 to S22. In step S21, as shown in FIG. 13, the synthesizing unit 42 synthesizes the partial image 94 obtained in step S20 described above next to the partial image 94 obtained in the previous routine. In the first routine, the synthesis unit 42 skips step S21.

  The left diagram of FIG. 13 shows partial images 94 obtained at the time of each imaging, and the middle diagram of FIG. 13 shows how a plurality of partial images 94 are combined. The right figure shows a state where all the partial images 94 are synthesized. In FIG. 13, as an example, “1” to “30”, which are the order in which the images were taken, are attached to each of the plurality of partial images 94. In step S21, each time the partial images 94 are obtained, the partial images 94 are combined. In addition, when the plurality of partial images 94 are all obtained, the plurality of partial images 94 are combined side by side in the imaging order. May be.

  Subsequently, in step S22, the synthesis unit 42 completes synthesis of all the partial images 94, that is, the partial images 94 corresponding to the entire circumference of the outer peripheral surface 12A (see FIG. 7) of the inspection target object 12. Determine whether or not.

  Here, when the synthesis unit 42 determines that the synthesis of all the partial images 94 has not been completed, the process returns to step S13 described above. Then, the above-described processing of step S13 to step S22 is repeatedly executed until the synthesizing unit 42 determines that the synthesis of all the partial images 94 has been completed.

  On the other hand, when the total number of partial images 94 is synthesized by repeatedly executing the processes of steps S13 to S22 described above, the synthesis unit 42 has completed the synthesis of the total number of partial images 94 in step S22. to decide. When the synthesis of all the partial images 94 is completed, a synthesized image 96 corresponding to the entire circumference of the outer peripheral surface 12A (see FIG. 7) of the inspection object 12 is generated by the synthesis unit 42.

(Reordering process)
The rearrangement process is executed in steps S23 to S24. In step S23, as shown in FIG. 14, the rearrangement unit 44 specifies the feature key position in the composite image 96 by template matching. In step S24, the rearrangement unit 44 rearranges the plurality of partial images 94 forming the composite image 96 in a predetermined order to generate an inspection image 98.

  The left diagram in FIG. 14 shows an example of the composite image 96 before the plurality of partial images 94 are rearranged, and the right diagram in FIG. 14 shows the result after the plurality of partial images 94 are rearranged. An example of the inspection image 98 is shown. In the present embodiment, for example, “+ abcdefg−” in the composite image 96 is designated as the feature key position, and the plurality of partial images 94 are rearranged so that the feature key position is arranged at a predetermined position.

(Difference processing)
The difference process is executed in step S25. In step S25, as shown in FIG. 15, the difference unit 46 generates a difference image 102 obtained by subtracting the inspection image 98 from the predetermined good product image 100. In the example shown in FIG. 15, a defective portion 104 is included in a part of the inspection image 98. The defective portion 104 is caused by, for example, a scratch, color loss, dent, or the like. In the example shown in FIG. 15, since the defective portion 104 is included in a part of the inspection image 98, the defective portion 104 also appears in the difference image 102. The defective portion 104 in the difference image 102 appears as a luminance difference from the surroundings.

(Determination process)
The determination process is executed in step S26. In step S26, as shown in FIG. 15, when there is a defective portion 104 in the difference image 102, the determination unit 48 determines that the outer peripheral surface 12A of the inspection object 12 shown in FIG. To do. On the other hand, when there is no defective portion 104 in the difference image 102, the determination unit 48 determines that the outer peripheral surface 12A of the inspection target object 12 shown in FIG.

  Next, the operation and effect of this embodiment will be described.

  In this embodiment, as shown in FIGS. 9 and 11, a part in the circumferential direction of the outer peripheral surface image 92 </ b> A obtained at the time of each imaging is extracted based on the inclination of the axis 12 </ b> C of the inspection object 12. An image 94 is generated. Then, as shown in FIG. 13, a composite image 96 is generated by combining a plurality of partial images 94 obtained by a plurality of imaging operations. Therefore, as shown in FIGS. 8 and 10, even when the axis 12C of the inspection object 12 is inclined with respect to the normal position, the influence of the inclination of the axis 12C of the inspection object 12 is eliminated. Can do. Thereby, the test | inspection precision in the case of automating the external appearance test | inspection of the to-be-inspected object 12 is securable.

  In addition, a pair of mirrors 16 are disposed on both sides in the axial direction of the inspection object 12, and mirror images 16 </ b> A of the pair of axial end surfaces 12 </ b> B reflected on the pair of mirrors 16 are captured by the camera 18. Therefore, the outer peripheral surface 12 </ b> A of the inspection object 12 and the pair of axial end surfaces 12 </ b> B on both sides can be simultaneously imaged by one camera 18. Accordingly, the number of cameras can be reduced as compared with the case where the outer peripheral surface 12A of the inspection target object 12 and the pair of axial end surfaces 12B on both sides are imaged by separate cameras. It can be simplified.

  Further, as shown in FIG. 8, when the axis 12C of the inspection object 12 is inclined with respect to the Y axis on the XY plane, as shown in the upper diagram of FIG. The center of gravity 92C of each axial end face image 92B is displaced in the X-axis direction. At this time, the inclination of the axis 12C of the inspection object 12 with respect to the Y axis on the XY plane is calculated based on the positional shift in the X axis direction at the center of gravity 92C of each of the pair of axial end face images 92B. . Further, the position in the Y-axis direction of the inspection object 12 is calculated based on the positions of the axial end portions 92D of the outer peripheral surface image 92A.

  Then, based on the inclination of the axis 12C of the inspection object 12 with respect to the Y axis on the XY plane and the position of the inspection object 12 in the Y axis direction, a part of the outer peripheral surface image 92A in the circumferential direction. Are extracted, and a partial image 94 is generated. Therefore, even when the axis 12C of the inspection object 12 is inclined with respect to the Y axis on the XY plane, the inclination of the axis 12C of the inspection object 12 with respect to the Y axis on the XY plane. The influence can be accurately eliminated.

  Further, as shown in FIG. 10, when the axis 12C of the inspection object 12 is inclined with respect to the Y axis on the YZ plane, as shown in the upper diagram of FIG. Each center of gravity 92C of the axial end face image 92B is displaced in the Y-axis direction. At this time, the inclination of the axis 12C of the inspection object 12 with respect to the Y axis on the YZ plane is calculated based on the positional shift in the Y axis direction at the center of gravity 92C of each of the pair of axial end face images 92B. . Further, the position in the Y-axis direction of the inspection object 12 is calculated based on the positions of the axial end portions 92D of the outer peripheral surface image 92A.

  Then, based on the inclination of the axis 12C of the inspection object 12 with respect to the Y axis on the YZ plane and the position of the inspection object 12 in the Y axis direction, a part of the outer peripheral surface image 92A in the circumferential direction. Are extracted, and a partial image 94 is generated. Therefore, even when the axis 12C of the inspection object 12 is inclined with respect to the Y axis on the YZ plane, the inclination of the axis 12C of the inspection object 12 with respect to the Y axis on the YZ plane is reduced. The influence can be accurately eliminated.

  In particular, when the partial image 94 is obtained in a trapezoidal shape due to the inclination of the axis 12C of the inspection object 12 with respect to the Y axis on the YZ plane, the trapezoidal partial image 94 is converted into the YZ. The rectangular shape is corrected based on the inclination of the axis 12C of the inspection object 12 with respect to the Y axis on the plane. Therefore, even when the axis 12C of the inspection object 12 is inclined with respect to the Y axis on the YZ plane, the plurality of partial images 94 can be appropriately combined. Thereby, the composite image 96 corresponding to the entire circumference of the outer peripheral surface 12A of the inspection object 12 can be accurately obtained.

  Next, modified examples other than those described in the embodiment will be described.

  In the above embodiment, the inspection object 12 is formed in a cylindrical shape, but may be formed in a columnar shape.

  Moreover, in the said embodiment, the calculation part 36 calculates the position of the to-be-inspected object 12 in the Y-axis direction in addition to the inclination of the axis 12C of the to-be-inspected object 12. Then, when the extraction unit 38 generates a partial image 94 by extracting a part of the outer peripheral surface image 92A in the circumferential direction, the positions of both end portions in the axial direction of the outer peripheral surface image 92A, that is, the inspection object 12 is detected. Consider the position in the Y-axis direction.

  However, for example, the calculation unit 36 calculates the inclination of the axis 12C of the inspection target object 12, and the extraction unit 38 determines one of the circumferential directions of the outer peripheral surface image 92A based on the inclination of the axis 12C of the inspection target object 12. The partial image 94 may be generated by extracting a part. Then, when the synthesizing unit 42 synthesizes the plurality of partial images 94, the positions of both end portions in the axial direction of the plurality of partial images 94 may be aligned.

  In the above embodiment, the inspection program 70 is stored (installed) in the storage unit 56 in advance. However, the inspection program 70 may be stored in the storage medium 62 such as a CD-ROM (Compact Disc Read Only Memory) or a DVD-ROM (Digital Versatile Disc Read Only Memory) shown in FIG. Further, the storage medium 62 for storing the inspection program 70 may be a USB (universal serial bus) memory 54 or the like in addition to the CD-ROM or DVD-ROM.

  In the above embodiment, a pair of mirrors 16 are arranged on both sides in the axial direction of the inspection object 12, and mirror images 16 </ b> A of the pair of axial end surfaces 12 </ b> B reflected on the pair of mirrors 16 are captured by the camera 18. The Then, the outer peripheral surface 12 </ b> A of the inspection object 12 and the pair of axial end surfaces 12 </ b> B on both sides are simultaneously imaged by one camera 18.

  However, by using the first camera that images the outer peripheral surface 12A of the inspection object 12 and the second camera that images the pair of axial end surfaces 12B on both sides, the outer peripheral surface 12A of the inspection object 12 The pair of axial end surfaces 12B on both sides may be imaged simultaneously.

  In the calculation process of the above embodiment, the inclination of the axis 12C of the inspection object 12 is calculated based on the position of the center of gravity 92C of each of the pair of axial end face images 92B. However, for example, the inclination of the axis 12C of the object 12 to be inspected may be calculated with reference to a position other than the center of gravity 92C, such as the outer shape of the pair of axial end face images 92B.

  As mentioned above, although one embodiment of the technique disclosed in the present application has been described, the technique disclosed in the present application is not limited to the above, and various modifications may be made without departing from the spirit of the present invention. Of course, it is possible.

  In addition, the following additional remark is disclosed regarding one Embodiment of the technique which the above-mentioned this application discloses.

(Appendix 1)
A rotation drive mechanism for rotating a cylindrical or columnar object to be inspected around an axis;
For each rotation of the inspection object, the outer peripheral surface of the inspection object and the pair of axial end surfaces on both sides are simultaneously imaged a plurality of times to obtain a plurality of outer peripheral surface images and a plurality of pairs of axial end surface images. A camera,
A calculation unit that calculates the inclination of the axis of the inspection object at the time of each imaging by the camera based on the positions of the pair of axial end face images obtained at the time of each imaging;
For each of the outer peripheral surface images obtained simultaneously with the pair of axial end surface images at the time of each imaging, a part in the circumferential direction of the outer peripheral surface image is extracted based on the inclination of the axis of the object to be inspected. An extraction unit for generating a partial image of
Combining a plurality of partial images to generate a combined image corresponding to the entire circumference of the outer peripheral surface of the inspection object;
An inspection apparatus for an object to be inspected.
(Appendix 2)
A pair of mirrors disposed on both sides in the axial direction of the object to be inspected;
The camera simultaneously captures an outer peripheral surface of the object to be inspected and a mirror image of the pair of axial end surfaces reflected on the pair of mirrors;
The inspection object inspection apparatus according to appendix 1.
(Appendix 3)
The rotation driving mechanism rotates the inspection object around the axis with the direction along the Y axis of the XY plane orthogonal to the optical axis of the camera as the axial direction of the inspection object.
The calculation unit is configured to detect the object to be inspected with respect to the Y axis on the XY plane based on a positional shift in the X axis direction of the XY plane at the center of gravity of each of the pair of axial end surface images. Calculating the inclination of the axis, and calculating the position of the inspection object in the Y-axis direction based on the positions of both ends in the axial direction of the outer peripheral surface image;
The extraction unit is configured to change a circumferential direction of the outer peripheral surface image based on an inclination of an axis of the inspection target with respect to a Y axis on the XY plane and a position of the inspection target in the Y axis direction. To extract a part of and generate the partial image,
The inspection apparatus for an object to be inspected according to appendix 2.
(Appendix 4)
The rotation driving mechanism rotates the inspection object around the axis with the direction along the Y axis of the XY plane orthogonal to the optical axis of the camera as the axial direction of the inspection object.
The calculation unit includes a Y axis on a YZ plane orthogonal to the XY plane based on a positional shift in the Y axis direction of the XY plane at the center of gravity of each of the pair of axial end face images. Calculating the inclination of the axis of the object to be inspected with respect to the Y axis direction position of the object to be inspected based on the positions of both ends in the axial direction of the outer peripheral surface image,
The extraction unit is configured to change the circumferential direction of the outer peripheral surface image based on the inclination of the axis of the inspection target object with respect to the Y axis on the YZ plane and the position of the inspection target object in the Y axis direction. To extract a part of and generate the partial image,
The inspection apparatus for an object to be inspected according to appendix 2 or appendix 3.
(Appendix 5)
The partial image obtained in a trapezoidal shape due to the inclination of the axis of the inspection target object with respect to the Y axis on the YZ plane is the shape of the inspection target object with respect to the Y axis on the YZ plane. A correction unit that corrects the rectangular shape based on the inclination of the axis;
The inspection object inspection apparatus according to appendix 4.
(Appendix 6)
A rearrangement unit that rearranges the plurality of partial images forming the composite image in a predetermined order to generate an inspection image;
The inspection apparatus for an object to be inspected according to any one of appendix 1 to appendix 5.
(Appendix 7)
A difference unit that generates a difference image obtained by subtracting the inspection image from a pre-defined good image;
A determination unit for determining the presence or absence of a defect in the outer peripheral surface of the inspection object based on the difference image;
Further comprising
The inspection object inspection apparatus according to appendix 6.
(Appendix 8)
On the computer,
Operate the rotary drive mechanism so that the cylindrical or columnar object to be inspected rotates around the axis,
The outer peripheral surface of the object to be inspected and the pair of axial end surfaces on both sides are simultaneously imaged a plurality of times per rotation of the object to be inspected to obtain a plurality of outer peripheral surface images and a plurality of pairs of axial end surface images. Operate the camera as
Calculating the inclination of the axis of the inspection object at the time of each imaging of the camera based on the position of the pair of axial end face images obtained at the time of each imaging;
For each of the outer peripheral surface images obtained simultaneously with the pair of axial end surface images at the time of each imaging, a part in the circumferential direction of the outer peripheral surface image is extracted based on the inclination of the axis of the object to be inspected. Generate a partial image of
Combining the plurality of partial images to generate a composite image corresponding to the entire circumference of the outer peripheral surface of the inspection object;
Inspection method for inspecting an object to be processed.
(Appendix 9)
Operate the camera so that the outer peripheral surface of the object to be inspected and the mirror images of the pair of axial end faces on the pair of mirrors arranged on both sides in the axial direction of the object to be inspected are simultaneously captured. Let
The inspection method for an inspection target object according to appendix 8.
(Appendix 10)
The rotation drive mechanism is operated so that the inspection object is rotated around the axis, with the direction along the Y axis of the XY plane orthogonal to the optical axis of the camera being the axial direction of the inspection object. Let
The inclination of the axis of the object to be inspected with respect to the Y axis on the XY plane is calculated based on the positional shift in the X axis direction of the XY plane at the center of gravity of each of the pair of axial end face images. And calculating the position in the Y-axis direction of the object to be inspected based on the positions of both end portions in the axial direction of the outer peripheral surface image,
Based on the inclination of the axis of the object to be inspected with respect to the Y axis on the XY plane and the position of the object to be inspected in the Y axis direction, a part in the circumferential direction of the outer peripheral surface image is extracted. And generating the partial image,
The inspection method for an inspection object according to appendix 9.
(Appendix 11)
The rotation drive mechanism is actuated so that the inspection object rotates about the axis, with the direction along the Y axis of the XY plane orthogonal to the optical axis of the camera as the axial direction of the inspection object. ,
The object to be inspected with respect to the Y axis on the YZ plane orthogonal to the XY plane based on a positional shift in the Y axis direction of the XY plane at the center of gravity of each of the pair of axial end face images Calculating the inclination of the axis of the object, and calculating the position of the inspection object in the Y-axis direction based on the positions of both ends in the axial direction of the outer peripheral surface image;
Based on the inclination of the axis of the object to be inspected with respect to the Y axis on the YZ plane and the position of the object to be inspected in the Y axis direction, a part of the outer peripheral surface image in the circumferential direction is extracted. And generating the partial image,
A method for inspecting an object to be inspected according to appendix 9 or appendix 10.
(Appendix 12)
In the computer,
The partial image obtained in a trapezoidal shape due to the inclination of the axis of the inspection target object with respect to the Y axis on the YZ plane is the shape of the inspection target object with respect to the Y axis on the YZ plane. Causing the processing to further include correcting to a rectangular shape based on the inclination of the axis,
The method for inspecting an inspection object according to appendix 11.
(Appendix 13)
In the computer,
Rearranging the plurality of partial images forming the composite image in a predetermined order to generate a test image;
The inspection method for an object to be inspected according to any one of appendix 8 to appendix 12.
(Appendix 14)
In the computer,
Generate a difference image obtained by subtracting the inspection image from a pre-defined good image,
Executing a process further comprising determining the presence or absence of a defect in the outer peripheral surface of the inspection object based on the difference image;
The inspection method for an inspection target object according to appendix 6.
(Appendix 15)
On the computer,
Operate the rotary drive mechanism so that the cylindrical or columnar object to be inspected rotates around the axis,
The outer peripheral surface of the object to be inspected and the pair of axial end surfaces on both sides are simultaneously imaged a plurality of times per rotation of the object to be inspected to obtain a plurality of outer peripheral surface images and a plurality of pairs of axial end surface images. Operate the camera as
Calculating the inclination of the axis of the inspection object at the time of each imaging of the camera based on the position of the pair of axial end face images obtained at the time of each imaging;
For each of the outer peripheral surface images obtained simultaneously with the pair of axial end surface images at the time of each imaging, a part in the circumferential direction of the outer peripheral surface image is extracted based on the inclination of the axis of the object to be inspected. Generate a partial image of
Combining the plurality of partial images to generate a composite image corresponding to the entire circumference of the outer peripheral surface of the inspection object;
An inspection program for an object to be inspected for executing processing including the above.
(Appendix 16)
On the computer,
Operate the rotary drive mechanism so that the cylindrical or columnar object to be inspected rotates around the axis,
The outer peripheral surface of the object to be inspected and the pair of axial end surfaces on both sides are simultaneously imaged a plurality of times per rotation of the object to be inspected to obtain a plurality of outer peripheral surface images and a plurality of pairs of axial end surface images. Operate the camera as
Calculating the inclination of the axis of the inspection object at the time of each imaging of the camera based on the position of the pair of axial end face images obtained at the time of each imaging;
For each of the outer peripheral surface images obtained simultaneously with the pair of axial end surface images at the time of each imaging, a part in the circumferential direction of the outer peripheral surface image is extracted based on the inclination of the axis of the object to be inspected. Generate a partial image of
Combining the plurality of partial images to generate a composite image corresponding to the entire circumference of the outer peripheral surface of the inspection object;
The storage medium which memorize | stored the test | inspection program of the to-be-inspected object which performs the process including this.

10 Inspection device (an example of “inspection device for inspection object”)
12 Inspection object 12A Outer peripheral surface 12B Axial end surface 12C Axis 14 Rotation drive mechanism 16 Mirror 16A Mirror image 18 Camera 18A Optical axis 20 Control unit 32 Rotation control unit 34 Imaging control unit 36 Calculation unit 38 Extraction unit 40 Correction unit 42 Synthesis unit 44 rearrangement unit 46 difference unit 48 determination unit 50 computer 56 storage unit (an example of “storage medium”)
62 Storage media (an example of “storage media”)
70 Inspection program (an example of an “inspection program for an object to be inspected”)
92A Peripheral surface image 92B Axial end surface image 92C Center of gravity 92D Axial end portions 94 Partial image 96 Composite image 98 Inspection image 100 Non-defective image 102 Difference image

Claims (6)

A rotation drive mechanism for rotating a cylindrical or columnar object to be inspected around an axis;
For each rotation of the inspection object, the outer peripheral surface of the inspection object and the pair of axial end surfaces on both sides are simultaneously imaged a plurality of times to obtain a plurality of outer peripheral surface images and a plurality of pairs of axial end surface images. A camera,
A calculation unit that calculates the inclination of the axis of the inspection object at the time of each imaging by the camera based on the positions of the pair of axial end face images obtained at the time of each imaging;
For each of the outer peripheral surface images obtained simultaneously with the pair of axial end surface images at the time of each imaging, a part in the circumferential direction of the outer peripheral surface image is extracted based on the inclination of the axis of the object to be inspected. An extraction unit for generating a partial image of
Combining a plurality of partial images to generate a combined image corresponding to the entire circumference of the outer peripheral surface of the inspection object;
An inspection apparatus for an object to be inspected. A pair of mirrors disposed on both sides in the axial direction of the object to be inspected;
The camera simultaneously captures an outer peripheral surface of the object to be inspected and a mirror image of the pair of axial end surfaces reflected on the pair of mirrors;
The inspection apparatus for an object to be inspected according to claim 1. The rotation driving mechanism rotates the inspection object around the axis with the direction along the Y axis of the XY plane orthogonal to the optical axis of the camera as the axial direction of the inspection object.
The calculation unit is configured to detect the object to be inspected with respect to the Y axis on the XY plane based on a positional shift in the X axis direction of the XY plane at the center of gravity of each of the pair of axial end surface images. Calculating the inclination of the axis, and calculating the position of the inspection object in the Y-axis direction based on the positions of both ends in the axial direction of the outer peripheral surface image;
The extraction unit is configured to change a circumferential direction of the outer peripheral surface image based on an inclination of an axis of the inspection target with respect to a Y axis on the XY plane and a position of the inspection target in the Y axis direction. To extract a part of and generate the partial image,
An inspection apparatus for an object to be inspected according to claim 2. The rotation driving mechanism rotates the inspection object around the axis with the direction along the Y axis of the XY plane orthogonal to the optical axis of the camera as the axial direction of the inspection object.
The calculation unit includes a Y axis on a YZ plane orthogonal to the XY plane based on a positional shift in the Y axis direction of the XY plane at the center of gravity of each of the pair of axial end face images. Calculating the inclination of the axis of the object to be inspected with respect to the Y axis direction position of the object to be inspected based on the positions of both ends in the axial direction of the outer peripheral surface image,
The extraction unit is configured to change the circumferential direction of the outer peripheral surface image based on the inclination of the axis of the inspection target object with respect to the Y axis on the YZ plane and the position of the inspection target object in the Y axis direction. To extract a part of and generate the partial image,
The inspection apparatus for an object to be inspected according to claim 2 or claim 3. The partial image obtained in a trapezoidal shape due to the inclination of the axis of the inspection target object with respect to the Y axis on the YZ plane is the shape of the inspection target object with respect to the Y axis on the YZ plane. A correction unit that corrects the rectangular shape based on the inclination of the axis;
An inspection apparatus for an object to be inspected according to claim 4. On the computer,
Operate the rotary drive mechanism so that the cylindrical or columnar object to be inspected rotates around the axis,
The outer peripheral surface of the object to be inspected and the pair of axial end surfaces on both sides are simultaneously imaged a plurality of times per rotation of the object to be inspected to obtain a plurality of outer peripheral surface images and a plurality of pairs of axial end surface images. Operate the camera as
Calculating the inclination of the axis of the inspection object at the time of each imaging of the camera based on the position of the pair of axial end face images obtained at the time of each imaging;
For each of the outer peripheral surface images obtained simultaneously with the pair of axial end surface images at the time of each imaging, a part in the circumferential direction of the outer peripheral surface image is extracted based on the inclination of the axis of the object to be inspected. Generate a partial image of
Combining the plurality of partial images to generate a composite image corresponding to the entire circumference of the outer peripheral surface of the inspection object;
Inspection method for inspecting an object to be processed.