JP6032993B2 - Outline inspection apparatus and outline inspection method - Google Patents

Description

  The present invention relates to an outline inspection apparatus and an outline inspection method.

  2. Description of the Related Art Conventionally, an external shape inspection apparatus that detects an abnormality of an inspection object from an image obtained by imaging a long inspection object is known (for example, Patent Document 1).

JP 2011-011496 A

  In this type of external shape inspection apparatus, in a situation where movement of an inspection object such as approach or separation from the imaging unit occurs, the size of the image changes with the movement, and it may be difficult to detect an abnormality in the external shape. there were.

  Therefore, as an example, an object of the present invention is to obtain an outline inspection apparatus and an outline inspection method that can more easily detect an abnormality in an outline.

In the outer shape inspection apparatus according to the embodiment of the present invention, the first image including both ends in the width direction of the inspection object is inspected in a state where the long inspection object is conveyed in the longitudinal direction. A first image obtained by imaging the object from a first direction intersecting the longitudinal direction and the width direction, and a second image including both ends of the inspection object in the width direction. The inspection object is different from the first direction in the longitudinal direction. and obtains a second image captured from a second direction which is crossing the width direction, the second with the inspection object is the width of the inspected object in the first image is increased when moving in a predetermined direction width of the inspection object in the image is reduced, the inspection object is inspected object in the second image with the width of the inspection object in the first image when moving in the opposite direction of the predetermined direction is reduced an imaging unit that is set as the width increases, the first picture processing A first width and combining data acquisition unit that acquires a value obtained by adding the second width of the second image object to be examined obtained by the image processing of the obtained test object Te, inspected from a value And an abnormality detection unit for detecting an abnormality of the object.

  According to the present invention, as an example, it is possible to obtain an outline inspection apparatus and an outline inspection method that can more easily detect an abnormality in the outline.

FIG. 1 is a perspective view illustrating an example of an outline inspection apparatus according to an embodiment. Drawing 2 is a mimetic diagram which looked at an example of the inspection part located in the upper stream side of the outline inspection device concerning an embodiment from the longitudinal direction of the inspection subject. Drawing 3 is a mimetic diagram which looked at an example of the inspection part located in the lower stream side of the outline inspection device concerning an embodiment from the longitudinal direction of the inspection subject. FIG. 4 is a schematic diagram illustrating an example of a first image, a second image, and a composite image captured by the outline inspection apparatus according to the embodiment. FIG. 5 is a schematic diagram illustrating an example of a composite image captured by the external shape inspection apparatus according to the embodiment. FIG. 6 is a graph showing an example of a change with time of width data (first data) obtained from an image captured by the outline inspection apparatus according to the embodiment. FIG. 7 is a graph showing an example of a temporal change of width data (second data) obtained from an image captured by the outline inspection apparatus according to the embodiment. FIG. 8 is a graph showing the data of FIG. 6 and the data of FIG. FIG. 9 is a graph in which one of the data in FIG. 6 and the data in FIG. 7 is shifted by a predetermined amount in the time direction with respect to the other. FIG. 10 is a graph of data obtained by combining the two data of FIG. FIG. 11 is a schematic block diagram illustrating an example of an outline inspection apparatus according to the embodiment. FIG. 12 is a schematic block diagram illustrating an example of a control unit of the external shape inspection apparatus according to the embodiment. FIG. 13 is a flowchart illustrating an example of an inspection method by the external shape inspection apparatus according to the embodiment. FIG. 14 is a schematic diagram illustrating another example of a composite image captured by the outline inspection apparatus according to the embodiment. FIG. 15 is a schematic diagram illustrating still another example of the composite image captured by the outline inspection apparatus according to the embodiment. FIG. 16 is a schematic explanatory diagram illustrating an enlarged part of an example of a composite image captured by the outline inspection apparatus according to the embodiment.

  In the present embodiment, as an example, the outer shape inspection apparatus 1 illustrated in FIG. 1 inspects the inspection object 100 based on an image obtained by imaging the inspection object 100. The inspection object 100 is, for example, a long and circular (or columnar) part (for example, a hose, a tube, a rod, etc.).

  In the present embodiment, as an example, as shown in FIG. 1, the outer shape inspection apparatus 1 includes a plurality of (in the present embodiment, two as an example) light sources 2U and 2D. Specifically, the light source 2U and the light source 2D are arranged apart from each other in the longitudinal direction (axial direction) of the inspection object 100. The light source 2U and the light source 2D are configured in an annular shape (for example, an annular shape). The light source 2U and the light source 2D have a plurality of LEDs (light emitting diodes) arranged in an annular shape. The elongate inspection object 100 passes through the inside (for example, the center and the center) of the annular portions of the light source 2U and the light source 2D, and extends along the axial direction of the annular portion. Further, the light source 2U and the light source 2D are arranged in plane symmetry with respect to a plane orthogonal to the longitudinal direction (axial direction) of the inspection object 100.

  In the present embodiment, as an example, the imaging region A of the inspection object 100 is set between the light source 2U and the light source 2D (in the present embodiment, an intermediate position as an example). The light from the light source 2U is applied to the imaging region A from one side in the longitudinal direction (left side in FIG. 1) of the inspection object 100, and the light from the light source 2D is from the other side in the longitudinal direction (right side in FIG. 1). The imaging area A is irradiated.

  In the present embodiment, as an example, the inspection object 100 is transported in the longitudinal direction (axial direction) by the transport device 30 (see FIG. 11) during the inspection. That is, the outer shape inspection apparatus 1 inspects the inspection object 100 that is transported and moved by the transport apparatus 30. Therefore, the imaging region A moves along the longitudinal direction of the inspection object 100 as the inspection object 100 moves. In the present embodiment, as an example, the inspection object 100 moves from the light source 2U side to the light source 2D side. That is, the light source 2U is positioned upstream in the transport direction with respect to the imaging region A, and the light source 2D is positioned downstream in the transport direction with respect to the imaging region A.

  In the present embodiment, as an example, the imaging unit 3 (for example, a camera or the like) is positioned on the radially outer side of the inspection target 100 and is an image of the surface 100a (outer surface, peripheral surface, side surface) of the inspection target 100. To get. That is, the imaging region A is a part of the surface 100a of the inspection target 100.

  In the present embodiment, as an example, the imaging unit 3 acquires an image of the imaging region A via the optical component 4. In the present embodiment, as an example, the optical component 4 is a plurality of (in the present embodiment, two as an example) mirrors 4U and 4L. Specifically, as shown in FIGS. 2 and 3, the mirrors 4 </ b> U and 4 </ b> L are arranged in a V shape with a line of sight from the axial direction on the opposite side of the inspection object 100 from the imaging unit 3. The mirrors 4U and 4L are arranged in a posture that is at an angle of approximately 120 ° to each other (an angle of approximately 60 ° on the opposite side with respect to the line L connecting the imaging unit 3 and the inspection object 100). Each of the mirrors 4U and 4L has a planar reflecting surface 4a (mirror surface) facing (opposed) to the surface 100a of the inspection object 100. The reflection surface 4a extends along a surface substantially orthogonal to the radial direction of the inspection object 100. Further, the mirrors 4U and 4L extend in a band shape along a plane orthogonal to the longitudinal direction (axial direction) of the inspection object 100. In such a configuration, the imaging area A is an area of about 70% facing the mirrors 4U and 4L in the entire circumference of the surface 100a of the inspection object 100. In the present embodiment, as an example, the adjacent mirrors 4U and 4L are integrated, but may be separated.

  Moreover, in this embodiment, the test | inspection part 10 (10U, 10D) containing the light sources 2U and 2D, the imaging part 3, and the optical component 4 as an example is the longitudinal direction (an axial direction, a conveyance direction) of the test target object 100. It is provided at a plurality of places (in this embodiment, two places as an example) at intervals. In these inspection units 10, the arrangement of the imaging unit 3 and the optical component 4 is different. In the present embodiment, as an example, in the inspection unit 10U located on the upstream side in the transport direction (left side in FIG. 1), as shown in FIG. 2, the right side as viewed from the upstream side in the axial direction of the inspection object 100 The imaging unit 3 is located at the left side, and the optical component 4 is located at the left side. Therefore, the imaging unit 3 of the inspection unit 10U acquires an image of the left region (imaging region A) of the inspection target 100 in FIG. On the other hand, in the inspection unit 10D positioned on the downstream side (right side in FIG. 1), as shown in FIG. 3, the imaging unit 3 is positioned on the left side with the line of sight from the upstream side in the axial direction of the inspection object 100. The optical component 4 is located in the position. Therefore, the imaging unit 3 of the inspection unit 10D acquires an image of the region on the right side (imaging region A) in FIG. That is, each of the plurality of imaging units 3 images different regions (parts, positions) of the surface 100a of the inspection object 100.

  In the present embodiment, as an example, the imaging unit 3 is configured as a line camera (line sensor). The imaging unit 3 has a plurality of photoelectric conversion elements (imaging elements, not shown) arranged in a line along the width direction of the inspection object 100. That is, the imaging unit 3 acquires a linear image (image data, luminance value data for each pixel corresponding to each photoelectric conversion element, luminance value data string) along the width direction of the inspection object 100. In each image sensor, luminance value data is acquired with, for example, 256 gradations. The imaging unit 3 acquires a one-dimensional image at each time (timing) when the imaging is performed. In the case of the monochrome (monochrome) imaging unit 3, one image data is acquired for each imaging device, and in the case of the color imaging unit 3, a plurality (for example, R (red) G (green) B (blue) is obtained for each imaging device. 3) of image data is acquired.

Moreover, in this embodiment, as an example, the light irradiation to the inspection object 100 by the light sources 2U and 2D is executed alternately. Then, imaging (acquisition of images) by the imaging unit 3 and irradiation of light to the inspection object 100 by the light sources 2U and 2D (for example, light emission and switching of the light sources 2U and 2D) are synchronized. That is, in the present embodiment, as an example, as illustrated in FIG. 4, the imaging unit 3 includes a one-dimensional image IL1 ( linear image, Image data (indicated as “1” in FIG. 4) and a one-dimensional image IL2 ( linear image, image data, in FIG. 4 “when illuminated by light from the light source 2D” 2) and alternately. The image processing unit 20d (see FIG. 12) is arranged to image IL1 of the inspection object 100 when being illuminated with light from the light source 2U are arranged in order of acquisition two-dimensional image IA1 (images data, the two-dimensional it is possible to obtain a data group) of the luminance values, the image IL2 of the inspection object 100 when being illuminated with light from the light source 2D side by acquisition order two-dimensional image IA2 (images data, arranged in a two-dimensional Data group of luminance values obtained).

  In the present embodiment, as an example, the switching frequency of the light from the light sources 2U and 2D, that is, the imaging frequency for each line by the imaging unit 3 is set to a relatively high value (for example, 6 kHz). Therefore, the images IA1 and IA2 are similar to images obtained by imaging the surface 100a of the inspection object 100 (an area of approximately 70% of the entire circumference) with the area sensor (imaging unit that images as a two-dimensional area) in a stationary state. Can be made. Since the line sensor has a relatively high resolution and a relatively high response compared to the area sensor, the use of the line sensor may enable more accurate abnormality detection (inspection). In the images IA1 and IA2, the arrangement direction of data in the included images IL1 and IL2 (left and right direction in FIG. 4) corresponds to the width direction (short direction) of the inspection object 100, and in the images IA1 and IA2. The direction in which the images IL1 and IL2 are arranged (the vertical direction in FIG. 4) corresponds to the longitudinal direction (axial direction) of the inspection object 100.

  In this embodiment, an image IC obtained by further combining (adding) the image IA1 and the image IA2 is obtained. In the synthesis of the image IC, the image IL1 and the image IL2 included in the images IA1 and IA2 and adjacent to each other (timing, time) are overlapped. As shown in FIG. 4, the images IL1 and IL2 that are adjacent to each other are shifted in timing by exactly one line. However, particularly when the light irradiation or imaging switching frequency is relatively high, It can be regarded as an image (image data) in almost the same place.

FIG. 5 shows an example of an image IC obtained by combining (adding) the image IA1 and the image IA2. As described above, the imaging unit 3 acquires an image of the inspection object 100 via a plurality of (in the present embodiment, two as an example) mirrors 4U and 4L. Each of the image ICs obtained by the configuration inspection apparatus 1 includes a plurality (two) of images Ia and Ib of the inspection object 100. Although not shown, images IA1 and IA2 also include images Ia and Ib. These images Ia and Ib are lines L (FIGS. 2 and 3) connecting the imaging unit 3 and the inspection object 100 on the opposite side of the inspection object 100 from the imaging unit 3 (the side where the mirrors 4U and 4L are located). It is an image viewed from a position deviating from (see). The two-dimensional image IC includes an image In that does not pass through the mirrors 4U and 4L of the inspection object 100 between the image Ia and the image Ib. Although not shown, the image In is also included in the images IA1 and IA2. However, in the present embodiment, as an example, the focus of the imaging unit 3 is set corresponding to the images Ia and Ib, and thus the image In is blurred. That is, in this embodiment, as an example, the image In is not used for abnormality detection. The backgrounds of these images Ia, Ib, and In are set dark. The image processing unit 20d (see FIG. 12) of the external shape inspection apparatus 1 according to the present embodiment performs image processing based on the two-dimensional image IC obtained in this manner, and the external shape (image) of the inspection object 100 The outer shape of Ia and Ib (for example, dimensions, size, interval, distance, positional relationship, etc.) is detected. As an example, the outer shape to be detected by the outer shape inspection apparatus 1 includes the widths Wa and Wb of the inspection object 100 as shown in FIG. Note that the outer shape inspection apparatus 1 can also detect an outer shape (abnormality) other than the width. The images IL1 and IL2 also include images Ia, Ib, and In (however, for one line). One of the images Ia and Ib is an example of a first image, and the other is an example of a second image.

  FIGS. 6 and 7 show examples of temporal changes in the width Wa of the image Ia and the value (data) of the width Ib of the image Ib corresponding to the inspection object 100 obtained from the synthesized image IC. The horizontal axis represents time t (timing, time) when the linear images IL1 and IL2 were obtained. As described above, since the inspection object 100 is conveyed in the longitudinal direction (axial direction), the horizontal axis corresponds to the position of the inspection object 100 in the longitudinal direction (axial direction). The vertical axis corresponds to the values (number of pixels) of the widths Wa and Wb. In the example of FIG. 6, it can be seen that the value of the width Wa decreases (gradually decreases) with time. On the other hand, in the example of FIG. 7, it can be seen that the value of the width Wb increases (gradually increases) over time. Such a phenomenon may be caused by the positional relationship between the mirrors 4U and 4L and the inspection object 100. That is, in the outer shape inspection apparatus 1, when the inspection object 100 moves downward in a situation where the inspection object 100 can move (vibrates) in the vertical direction, the inspection object 100 moves from the mirror 4U as it moves downward. Since they are separated from each other, the value of the width Wa obtained from the image Ia of the inspection object 100 acquired through the mirror 4U decreases with the passage of time. Further, since the inspection object 100 moves closer to the mirror 4L as it moves downward, the value of the width Wb obtained from the image Ib of the inspection object 100 acquired through the mirror 4L is increased with time. Increase. That is, the results as shown in FIGS. Although not shown, conversely, when the inspection object 100 moves upward, the inspection object 100 comes closer to the mirror 4U as it moves upward, and thus the inspection object acquired through the mirror 4U. The value of the width Wa obtained from 100 images Ia increases with time. Further, since the inspection object 100 moves away from the mirror 4L as it moves upward, the value of the width Wb obtained from the image Ib of the inspection object 100 acquired through the mirror 4L is increased with time. Decrease. As described above, the change in the value of the width Wa of the image Ia or the width Wb of the image Ib may include a component based on the movement of the inspection object 100. Therefore, when detecting the external shape (size, size, interval, distance, positional relationship, etc.) of the inspection object 100 or its abnormality based on the values of the widths Wa and Wb, the influence of the movement of the inspection object 100 is detected. Is preferably removed.

  As a result of intensive studies, the inventor has studied the outline data based on the image Ia (value, first data, for example, the value of the width Wa) and the outline data based on the image Ib (value, It has been found that the influence of the movement of the inspection object 100 can be easily reduced by combining (adding) the second data, for example, the value of the width Wb. Specifically, for example, as shown in FIGS. 6 and 7, when the value of the width Wa decreases with time and the value of the width Wb increases with time, the width Wa In the value obtained by combining (adding) the value and the value of the width Wb, the decrease and increase over time are reduced (offset). As described above, when detecting an abnormality in the outer shape of the inspection object 100 based on the data based on the image Ia and the data based on the image Ib, the data based on the image Ia and the data based on the image Ib are combined ( By adding), the influence of the movement of the inspection object 100 can be easily reduced. Note that such synthesis (addition) of data is equivalent to calculating an average of data based on the image Ia and data based on the image Ib.

  Furthermore, the inventor has found the following problems as a result of intensive studies. That is, as shown in FIGS. 6 and 7, the values of the widths Wa and Wb fluctuate periodically. For example, as shown in FIG. 5, an inspection object 100 (for example, a hose) has a wound object 100b (for example, a tape, a ribbon, a strip, etc.) that is spirally wound at a constant pitch. In such a case, the images Ia and Ib include periodic uneven shapes (steps) corresponding to the interval (pitch) of the boundary portion 100c of the wound product 100b. Then, as shown in FIG. 8, when the value (data) of the width Wa in FIG. 6 and the value (data) of the width Wb in FIG. 7 are arranged side by side, the fluctuation of the value of the width Wa and the fluctuation of the value of the width Wb. It can be seen that the period is the same, but the phase is shifted by the time δt (the phase is different and there is a phase difference). As apparent from FIG. 5, this phase difference corresponds to the number of pixels d (time δt) in the time direction (the axial direction and the longitudinal direction of the inspection object 100). This is because the images are taken from different directions along the line. Then, from the value (data) obtained by combining (adding) the value of the width Wa and the value of the width Wb in a state where there is such a phase difference, a change in the value based on the periodic fluctuation of the widths Wa and Wb is observed. There is a risk of being reduced (offset).

  Therefore, in the present embodiment, as an example, as shown in FIG. 9, the outer shape data (value, first data, for example, width Wa) based on the image Ia and the outer shape data (value, first data based on the image Ib). The two data, for example, the width Wb) are shifted by a predetermined amount corresponding to the phase difference in the time direction (the axial direction and the longitudinal direction of the inspection object 100) to match their periodic fluctuations. It can be understood from FIG. 9 that the phase of the periodic fluctuation of the value of the width Wa and the phase of the periodic fluctuation of the value of the width Wb substantially coincide. Then, with the phase difference reduced in this way, the value of the width Wa and the value of the width Wb are combined (added). FIG. 10 shows the value (data) of the width Wd obtained by synthesizing the value of the width Wa and the value of the width Wb of FIG. 9 with the phase corrected. As apparent from FIG. 10, the data of the width Wd synthesized (added) in this way reduces the influence of the increase or decrease over time associated with the movement of the inspection object 100, and the data of the width Wd. The component of periodic fluctuations remains.

  In the present embodiment, as an example, as shown in FIG. 11, the outline inspection apparatus 1 includes a control unit 20 (for example, a CPU (central processing unit)), a ROM 21 (read only memory), a RAM 22 (random access memory). SSD 23 (solid state drive), light irradiation controller 24, imaging controller 25, transport controller 26, display controller 27, and the like. The light irradiation controller 24 controls light emission (ON, OFF) and the like of the light sources 2U and 2D based on a control signal from the control unit 20. Note that when a variable device such as a shutter that switches between opening and closing of light by switching between opening and closing is provided, the operation of the variable device is controlled. The imaging controller 25 controls imaging by the imaging unit 3 based on a control signal from the control unit 20. The transport controller 26 controls the transport device 30 based on the control signal received from the control unit 20 and controls transport (start, stop, speed, etc.) of the inspection object 100. The display controller 27 controls the display device 40 based on a control signal from the control unit 20. Further, the control unit 20 reads and executes a program (application) installed in the ROM 21 or the SSD 23 as a nonvolatile storage unit. The RAM 22 temporarily stores various data used when the control unit 20 executes programs and executes various arithmetic processes. Note that the hardware configuration shown in FIG. 11 is merely an example, and can be implemented with various modifications such as a chip or a package. Various arithmetic processes can be performed in parallel, and the control unit 20 or the like can have a hardware configuration capable of parallel processing.

  In the present embodiment, as an example, the control unit 20 functions (operates) as at least a part of the outer shape inspection apparatus 1 in cooperation with hardware and software (program). That is, as illustrated in FIG. 12, the control unit 20 functions as a light irradiation control unit 20a, an imaging control unit 20b, a conveyance control unit 20c, an image processing unit 20d, a display control unit 20e, and the like. The light irradiation control unit 20 a controls the light irradiation controller 24. The imaging control unit 20b controls the imaging controller 25. The conveyance control unit 20 c controls the conveyance controller 26. The image processing unit 20d performs image processing on the image data acquired by the imaging unit 3. An abnormality of the inspection object 100 is detected by the image processing by the image processing unit 20d. Therefore, the image processing unit 20d is an example of an abnormality detection unit. The display control unit 20e controls the display device 40 (for example, an LCD (liquid crystal display), an OELD (organic electroluminescent display), etc.).

  Further, the outer shape inspection apparatus 1 according to the present embodiment can inspect the inspection object 100 having a spiral concave portion or convex portion on the outer periphery thereof. A spiral recess or projection (groove, protrusion, step, etc.) is likely to be formed when a spiral wound (eg, tape, ribbon, wire, etc., not shown) is included. There are some which are exposed to the outer periphery and some which are not exposed. When the wound product is not exposed to the outer periphery and a wound product (for example, a wire) is provided inside the outer wall (wall portion), the portion covering the wound product protrudes in a spiral shape.

  In the present embodiment, as an example, the control unit 20 of the outer shape inspection apparatus 1 executes image processing and abnormality detection according to a procedure as shown in FIG. The control unit 20 functions as the light irradiation control unit 20a and the imaging control unit 20b in a state where the inspection object 100 is moving at a constant speed, and the light irradiation controller 24, the imaging controller 25, and the light sources 2U and 2D, and the imaging unit. 3 is controlled to alternately obtain one-dimensional images IL1 and IL2 (step S10). Next, the control unit 20 functions as the image processing unit 20d, and arranges a plurality of columns of images IL1 and IL2 in the order obtained in a predetermined period as described above, and generates two-dimensional images IA1 and IA2. Is obtained (step S11). Next, the control unit 20 functions as the image processing unit 20d, and combines (adds) the image IA1 and the image IA2 as described above to obtain an image IC (step S12). Note that the image IC is not necessarily generated via the image IA1 and the image IA2, and may be generated from the image IL1 and the image IL2.

  Next, the control unit 20 functions as the image processing unit 20d and detects the edges of the images Ia and Ib (step S13). Here, an edge means the edge part (edge part) of the both sides of the width direction (The width direction of the test target object 100, the left-right direction of FIG. 5) of the images Ia and Ib. In this step S13, since the appearance positions of the images Ia and Ib are almost fixed, the control unit 20 changes the values of the edges of the images Ia and Ib from the data binarized according to the threshold value, for example. It can be detected as a position to perform.

  Next, the control unit 20 functions as the image processing unit 20d and calculates the widths Wa and Wb of the images Ia and Ib (step S14). In step S14, the values of the widths Wa and Wb can be calculated as, for example, the distance between two edges for each of the images Ia and Ib detected in step S13. Further, the values of the widths Wa and Wb are calculated every time t (timing, time) when data is acquired, that is, at each position in the longitudinal direction of the images Ia and Ib. The data of the width Wa is an example of the first data, and the data of the width Wb is an example of the second data.

  Here, in the present embodiment, as an example, when the phase is shifted as described above (Yes in step S15), the control unit 20 is time-dependent of the value of width Wa (data) and the value of width Wb (data). One of the changes is shifted from the other by a predetermined amount in the time direction, and is synthesized (added) every time to obtain the value (data, synthesized data) of the width Wd at each time (step S16). In step S16, the shift amount δt in the time direction of the time-dependent data (predetermined amount, the number of pixels corresponding to the phase difference, see FIG. 8) is used to determine the layout of each component in the inspection unit 10 and the specifications of the inspection object 100. It is determined according to (size, pitch of the roll 100b) and the like. Therefore, as an example, it can be acquired and set in advance trial or the like. Strictly speaking, the width Wd does not correspond to an actual measurement value, but corresponds to a value (parameter, representative value) used for abnormality detection or the like.

  On the other hand, when the phase is not particularly shifted (No in step S15), the control unit 20 synthesizes (adds) the value (data) of the width Wa and the value (data) of the width Wb for each time. The value (data, composite data) of the width Wd in time is acquired (step S17).

  Next, the control unit 20 functions as the image processing unit (abnormality detection unit) 20d, and changes with time in the value (data) of the width Wd synthesized in step S16 or step S17 (that is, as an example, the data in FIG. 10). ) Is detected (step S18). In this step S18, as an example, as shown in FIG. 16, the control unit 20 has a width Wd in a predetermined section in the time direction (longitudinal direction of the inspection object 100, axial direction, horizontal axis direction in FIGS. 10 and 16). Based on the integrated value (area and size of hatched areas Aa to Ae in FIG. 16) of the difference between the average value Wav of the values and the value of the width Wd at each time (rectangle in FIG. 16) When the integral value is equal to or exceeds the threshold value, it can be determined that there is an abnormality at the location (for example, the region Aa in FIG. 16). In this case, the integral value corresponds to a value (parameter, representative value) corresponding to a two-dimensional size of an abnormal portion (for example, a convex portion, a concave portion, a protrusion, or a step) in the captured images Ia and Ib. To do. In step S18, the control unit 20 has a concavo-convex shape (for example, a concave portion, a convex portion, a protrusion, a step, etc.) appearing at a boundary portion 100c between the wound material 100b and the wound material 100b in the images Ia and Ib. Is not detected as abnormal.

  Next, the control unit 20 functions as the display control unit 20e and displays the abnormality detected in step S18 on the display screen of the display device 40 (step S19). In step S19, the control unit 20 indicates, for example, an abnormality (an arrow, a mark, a character, a figure, or the like) in the image Ia or the image Ib as shown in FIGS. ) Can be displayed. At this time, when the phase is shifted in step S16, the control unit 20 displays an index indicating the abnormality at a position corresponding to the abnormality in the image Ia or the image Ib in consideration of the shifted amount.

  For example, the control unit 20 of the outline inspection apparatus 1 according to the present embodiment described above can detect an abnormality as shown in FIGS. In the example of FIG. 5, the control unit 20 can detect the convex portion A1 (protrusion) in the image Ia and the convex portion A2 (protrusion) in the image Ib as abnormal. In this example, the convex part A1 and the convex part A2 may be one (the same, one block) convex part. In order to detect such an abnormality, in step S16, the control unit 20 sets the value of the width Wa or the value of the width Wb so that corresponding portions (adjacent portions or the same portion) in the images Ia and Ib overlap each other. Shift to In the example of FIG. 14, the control unit 20 can detect the concave portion A3 in the image Ia and the concave portion A4 in the image Ib as abnormal. In this example, the recess A3 and the recess A4 may be one (the same, a lump) recess. In the example of FIG. 15, the control unit 20 can detect the concave portion A5 in the image Ia and the convex portion A6 in the image Ib as abnormal. In this example, the concave portion A5 and the convex portion A6 are different abnormalities. Even in such a case, the control unit 20 can detect the abnormality by appropriately setting the threshold value.

As described above, in the outer shape inspection apparatus 1 according to the present embodiment, as an example, the imaging unit 3 causes the image Ib (when the inspection object 100 becomes large in the image Ia ( for example, the first image)). For example, when the inspection object 100 in the second image) becomes small and the inspection object 100 becomes small in the image Ia, the inspection object 100 in the image Ib is set large. Then, the image processing unit 20d (abnormality detection unit) obtains the data (first data) of the width Wa corresponding to the outer shape of the inspection object 100 obtained by image processing of the image Ia and the image Ib by image processing. The abnormality of the inspection object 100 is detected from the data (composite data) of the width Wd obtained by combining (adding) the data (second data) of the width Wb corresponding to the outer shape of the inspection object 100 thus obtained. Therefore, according to the present embodiment, as an example, the influence of the movement of the inspection object 100 on the detection of the abnormality of the outer shape of the inspection object 100 is easily reduced.

  In the present embodiment, as an example, one of the image Ia and the image Ib is an image obtained by imaging the inspection object 100 from the upper side, and the other is an image obtained by imaging from the lower side. The inspection object 100 may be easily moved in the vertical direction by the action of gravity. Therefore, according to the present embodiment, as an example, in such a case, the influence of the movement of the inspection object 100 on the detection of the abnormality in the outer shape of the inspection object 100 is easily reduced.

  In the present embodiment, as an example, the imaging unit 3 acquires images of a plurality of parts via the optical component 4 (mirrors 4U and 4L) that refracts or reflects light. Therefore, according to the present embodiment, as an example, a configuration for acquiring images of a plurality of parts is easily obtained as a simpler configuration. When the optical component 4 in which the two mirrors 4U and 4L are integrated is used, it becomes easier to handle the mirrors 4U and 4L at the time of manufacturing and maintenance of the external shape inspection apparatus 1.

  In this embodiment, as an example, the image processing unit 20d (composite data acquisition unit) synthesizes the data of the width Wa and the data of the width Wb by shifting in a direction corresponding to the longitudinal direction (time direction). In the present embodiment, as an example, the image processing unit 20d (composite data acquisition unit) performs a data variation according to the data pitch of the width Wa and a data variation according to the data pitch of the width Wb. The data of the width Wa and the data of the width Wb are shifted and combined so that the phase difference is reduced. Therefore, according to the present embodiment, as an example, when the data of the width Wa and the data of the width Wb fluctuate periodically and the phase of the periodic fluctuation is shifted, the data of the width Wa and the width Wb It is suppressed that the component of the periodic fluctuation is reduced (cancelled) by combining (adding) the data. Therefore, as an example, an abnormality in the outer shape of the inspection object 100 is easily detected with high accuracy in a state where there is periodic fluctuation.

  Further, in the present embodiment, as an example, the inspection object 100 has a wound object 100b wound spirally at a constant pitch. In the present embodiment, as an example, the inspection object 100 is a long component having a spiral concave portion or convex portion on the outer periphery. Therefore, according to the present embodiment, as an example, an abnormality in the outer shape of the inspection target object 100 in which the data of the width Wa and the data of the width Wb fluctuate periodically can be detected more accurately.

  As mentioned above, although embodiment of this invention was illustrated, the said embodiment is an example to the last. The embodiment can be implemented in various other forms, and various omissions, replacements, combinations, and changes can be made without departing from the scope of the invention. In addition, the configuration and shape of the embodiment can be partially replaced with other configurations and shapes. In addition, specifications (structure, type, direction, angle, shape, size, length, width, thickness, height, number, arrangement, position, material, etc.) of each configuration, shape, etc. are changed as appropriate. Can be implemented. For example, the inspection object may be other than an elongated part. Moreover, the external shape inspection apparatus can detect abnormalities other than the abnormalities described above by image processing. The external shape inspection apparatus may inspect with an image acquired in a stationary state. The optical component may be other than a mirror (for example, a lens, a prism, etc.). Further, three or more parts of the inspection object may be included in the image. Further, the imaging unit may acquire a linear image extending in a direction crossing the width direction (oblique direction).

  DESCRIPTION OF SYMBOLS 1 ... External shape inspection apparatus, 3 ... Imaging part, 4 ... Optical component, 20d ... Image processing part (synthetic data acquisition part, abnormality detection part), 100 ... Inspection object, 100b ... Rolled object.

Claims (7)

In a state where a long inspection object is conveyed in the longitudinal direction, the inspection object is a first image including both ends in the width direction, and the inspection object is crossed with the longitudinal direction and the width direction . A first image captured from a first direction and a second image including both ends in the width direction of the inspection object , wherein the inspection object is crossed with the longitudinal direction and the width direction , unlike the first direction. and a second image captured from the second direction, acquires the second image in conjunction with the inspection object is the width of the inspected object is large in the first image when moving in a predetermined direction the width of said test object is reduced, together with the inspection object is the width of the test object is reduced in the first image when moving in the opposite direction of the predetermined direction of the second in the image setting of such a width of the test object is larger And the imaging unit was,
The first of the width and the second of said width and the value obtained by adding the second image the inspection object obtained by the image processing of the inspection object obtained by the image processing said first image A synthetic data acquisition unit for acquiring
An abnormality detection unit for detecting an abnormality of the inspection object from the value ;
An external form inspection apparatus.   The external inspection apparatus according to claim 1, wherein one of the first image and the second image is an image obtained by imaging the inspection object from above, and the other is an image obtained by imaging from the lower side.   The external shape inspection apparatus according to claim 1, wherein the imaging unit acquires the first image and the second image via an optical component that refracts or reflects light. The synthesized data acquisition unit corresponds to the first data indicating the first width at each position in the longitudinal direction and the second data indicating the second width at each position in the longitudinal direction in the longitudinal direction. The external shape inspection apparatus according to claim 1, wherein the outer shape inspection apparatus is combined in a shifted direction.   The external inspection apparatus according to claim 4, wherein the inspection object has a wound object that is spirally wound at a constant pitch.   The composite data acquisition unit is configured to reduce the phase difference between the data variation according to the pitch of the first data and the data variation according to the pitch of the second data. The external shape inspection apparatus according to claim 5, wherein the two data are combined while being shifted. An external form inspection method using an external form inspection apparatus that detects an abnormality of an inspection object by performing image processing on an image of the inspection object that is imaged in a state where a long inspection object is conveyed in a longitudinal direction. ,
The outline inspection apparatus is
A first image including both ends of the inspection object in the width direction, the first image obtained by imaging the inspection object from a first direction crossing the longitudinal direction and the width direction, and the width direction of the inspection object comprising the steps of: obtaining a second image, a where the second image is a by the test object imaged from a second direction which is crossing with the longitudinal direction and the width direction different from the first direction including the opposite ends of When the inspection object moves in a predetermined direction, the width of the inspection object in the first image is increased and the width of the inspection object in the second image is reduced, so that the inspection object is Is set so that the width of the inspection object in the first image is reduced and the width of the inspection object in the second image is increased when moving in the direction opposite to the predetermined direction. ,
Obtained by adding the second of the width before Symbol the inspection object to the second image and the first of the width of the object to be examined obtained by the first image and image processing obtained by the image processing Obtaining a value;
Detecting an abnormality of the inspection object from the value ;
Perform the outline inspection method.