Inspection device and inspection method

Abstract

To improve the accuracy of inspecting an object including an assembled component.SOLUTION: An inspection device according to an embodiment inspects objects including holes and components that are inserted into the holes, and comprises: a plurality of light sources that sequentially illuminates an area including the holes from different directions; a camera that generates a plurality of pieces of image data of the area that is sequentially illuminated by the plurality of light sources; and a controller that determines if the components are normally inserted into the holes on the basis of shadows included in the plurality of pieces of image data generated by the camera.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an inspection apparatus and an inspection method for performing an inspection on the assembly of parts.

Background Art

[0002] In a manufacturing process of a product or the like, when an assembly of some parts is performed, an inspection may be carried out to determine whether the assembly is properly performed. For such an inspection, for example, image data obtained by imaging an object with a camera is used.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the conventional inspection using the above-described image data, it is difficult to accurately determine whether the assembly is good or bad depending on the shape and posture of the object to be inspected. Therefore, one of the objects of the present invention is to improve the inspection accuracy of an object including assembled parts.

Means for Solving the Problems

[0005] An inspection apparatus according to an embodiment inspects an object including a hole and a part inserted into the hole, and includes a plurality of light sources that sequentially illuminate a region including the hole from different directions, a camera that generates a plurality of image data of the region sequentially illuminated by the plurality of light sources, and a controller that determines whether the part is normally inserted into the hole based on a shadow included in each of the plurality of image data generated by the camera.

[0006] An inspection method according to an embodiment inspects an object including a hole and a component inserted into the hole, sequentially illuminates a region including the hole from different directions by a plurality of light sources, generates a plurality of image data of the region sequentially illuminated by the plurality of light sources by a camera, and determines whether the component is normally inserted into the hole based on a shadow included in each of the plurality of image data generated by the camera.

Advantages of the Invention

[0007] For example, according to the present invention, it is possible to improve the inspection accuracy of an object including an assembled component.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0009] Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of an inspection apparatus 1 according to the present embodiment. The inspection apparatus 1 performs an inspection on an object 100. The object 100 includes a base member 110 and a component 120 assembled to the base member 110.

[0010] The inspection apparatus 1 includes a camera 2 that images the object 100, light sources 31 to 34 that illuminate the object 100, a moving mechanism 4, and a controller 5. Note that the number of light sources included in the inspection apparatus 1 is not necessarily limited to the four light sources 31 to 34, and two or more may be sufficient.

[0011] The moving mechanism 4 relatively moves the camera 2 and the object 100. In the present embodiment, it is assumed that the moving mechanism 4 moves the camera 2 and the light sources 31 to 34 with respect to the object 100 disposed at the inspection position. As another example, the moving mechanism 4 may move the object 100 with respect to the fixedly arranged camera 2 and light sources 31 to 34.

[0012] The controller 5 includes a camera control unit 50 that controls the camera 2, a light source control unit 51 that controls the light sources 31 to 34, a movement control unit 52 that controls the movement mechanism 4, and an analysis unit 53 that analyzes the image data generated by the camera 2. For example, the camera control unit 50, the light source control unit 51, the movement control unit 52, and the analysis unit 53 are software modules realized by a processor executing a computer program. The camera control unit 50, the light source control unit 51, the movement control unit 52, and the analysis unit 53 may be realized by different processors and computer programs, respectively. Also, at least one of the camera control unit 50, the light source control unit 51, the movement control unit 52, and the analysis unit 53 may be realized by a hardware module or by the cooperation of a software module and a hardware module.

[0013] The inspection device 1 may further include an assembling device 6 for assembling the component 120 to the base member 110 of the object 100. In this case, the controller 5 may further include an assembling control unit 54 that controls the assembling device 6. Note that the assembling device 6 and the assembling control unit 54 may be part of a manufacturing device including the inspection device 1.

[0014] FIG. 2 is a schematic plan view showing the relationship between the object 100 and the light sources 31 to 34. The base member 110 of the object 100 has, for example, an assembling surface 111 that is a plane, and a plurality of holes H (Ha, Hb, Hc, Hd) provided in the assembling surface 111. The light sources 31 to 34 illuminate at least the region A indicated by the dashed rectangular frame in the figure. The region A includes the holes Ha, Hb, Hc, Hd.

[0015] Here, as shown in FIG. 2, the X direction, the Y direction, and the Z direction that are orthogonal to each other are defined. Both the X direction and the Y direction are parallel to the assembling surface 111. The Z direction is orthogonal to the assembling surface 111. In the following description, looking at the object 100 parallel to the Z direction is referred to as a plan view.

[0016] The holes Ha, Hb, Hc, and Hd are all circular in plan view. The holes Ha, Hb, Hc, and Hd are arranged in the arrangement direction Dr. In the example of FIG. 2, the arrangement direction Dr is parallel to the X direction. Parts 120 are inserted into the holes Ha, Hb, Hc, and Hd, respectively.

[0017] The light source 31 emits light in the illumination direction D1, the light source 32 emits light in the illumination direction D2, the light source 33 emits light in the illumination direction D3, and the light source 34 emits light in the illumination direction D4. The illumination directions D1 to D4 are different from each other. When viewed in plan as shown in FIG. 2, the illumination directions D1 and D2 are parallel to the X direction and are opposite to each other. Also, when viewed in plan as shown in FIG. 2, the illumination directions D3 and D4 are parallel to the Y direction and are opposite to each other.

[0018] FIG. 3 is a schematic cross-sectional view showing the relationship between the object 100 and the illumination directions D1 and D2. Also, FIG. 4 is a schematic cross-sectional view showing the relationship between the object 100 and the illumination directions D3 and D4. The cross-section shown in FIG. 3 corresponds to an X-Z cross-section defined by the X direction and the Z direction. The cross-section shown in FIG. 4 corresponds to a Y-Z cross-section defined by the Y direction and the Z direction.

[0019] As shown in FIG. 3, the illumination directions D1 and D2 are inclined with respect to the mounting surface 111. The illumination direction D1 forms an angle θ1 with the mounting surface 111, and the illumination direction D2 forms an angle θ2 with the mounting surface 111.

[0020] Also, as shown in FIG. 4, the illumination directions D3 and D4 are inclined with respect to the mounting surface 111. The illumination direction D3 forms an angle θ3 with the mounting surface 111, and the illumination direction D4 forms an angle θ4 with the mounting surface 111.

[0021] In the present embodiment, it is assumed that the angles θ1 to θ4 are the same. In one example, the angles θ1 to θ4 are 60 degrees or more, but the present invention is not limited to this example.

[0022] The imaging direction Dm by the camera 2 is parallel to the Z direction, for example. Also, the axes of the holes Ha, Hb, Hc, and Hd are parallel to the Z direction.

[0023] As shown in FIGS. 2 to 4, the component 120 has a first portion 121 and a second portion 122 connected to the first portion 121. The first portion 121 and the second portion 122 are both, for example, columnar (or cylindrical).

[0024] In the examples of FIGS. 3 and 4, the first portion 121 is entirely received in each of the holes Ha, Hb, Hc, Hd. For example, the lower end of the first portion 121 is in contact with the bottom surface of each of the holes Ha, Hb, Hc, Hd. Also, a part of the second portion 122 protrudes from each of the holes Ha, Hb, Hc, Hd.

[0025] The assembling device 6 shown in FIG. 1 inserts the component 120 into each of the holes Ha, Hb, Hc, Hd. FIGS. 2 to 4 show the state in which the component 120 is normally inserted into each of the holes Ha, Hb, Hc, Hd. However, an assembling abnormality may occur in which the component 120 is not normally inserted into the holes Ha, Hb, Hc, Hd.

[0026] FIG. 5 is a schematic cross-sectional view showing an example of an assembling abnormality. The cross-section shown in this figure corresponds to the X-Z cross-section of the object 100, similar to FIG. 3.

[0027] In the example of FIG. 5, the component 120 is normally inserted into the hole Ha. On the other hand, in the hole Hb, the component 120 is inserted in an inclined state. Also, in the hole Hc, the second portion 122 is missing from the component 120, and only the first portion 121 is inserted into the hole Hc. Further, the component 120 is not inserted into the hole Hd.

[0028] The inspection device 1 and the inspection method according to this embodiment detect such assembling abnormalities. Specific examples of the operation of the inspection device 1 and the inspection method are shown below.

[0029] FIG. 6 is a flowchart showing an example of the assembly of component 120 to base member 110 and the inspection after this assembly. When assembling component 120, first, camera 2 and light sources 31 to 34 and object 100 (here, base member 110 with component 120 not inserted) are positioned so that region A shown in FIG. 2 faces camera 2 directly (step S1). This operation can be realized, for example, by the movement control unit 52 controlling the movement mechanism 4 based on the image data sequentially generated by camera 2.

[0030] After step S1, the camera control unit 50 causes camera 2 to image region A (step S2). Further, the analysis unit 53 detects the positions of holes Ha, Hb, Hc, and Hd in the image data obtained by the imaging in step S2 (step S3). The imaging in step S2 may be performed with light sources 31 to 34 turned off, or may be performed with at least one of light sources 31 to 34 turned on.

[0031] FIG. 7 is a diagram showing an example of the image data IMG0 generated in step S2. For example, the image data IMG0 is obtained by binarizing the grayscale or color multi-tone image data generated by camera 2. The image data IMG0 includes a shaded portion Pa corresponding to hole Ha, a shaded portion Pb corresponding to hole Hb, a shaded portion Pc corresponding to hole Hc, and a shaded portion Pd corresponding to hole Hd.

[0032] In step S3, the analysis unit 53 detects, as the positions of holes Ha, Hb, Hc, and Hd, for example, the centers of holes Ha, Hb, Hc, and Hd (the cross marks in the figure). The centers of holes Ha, Hb, Hc, and Hd can be detected, for example, by approximating the outer shapes of the shaded portions Pa, Pb, Pc, and Pd to perfect circles respectively and calculating the coordinates of these centers.

[0033] After step S3, the component 120 is inserted into each of the holes Ha, Hb, Hc, and Hd by the assembling device 6 (step S4). For the insertion of this component 120, the coordinates of the centers of the holes Ha, Hb, Hc, and Hd detected in step S3 can be used. That is, the assembling device 6 inserts the component 120 parallel to the Z direction with respect to the holes Ha, Hb, Hc, and Hd so that the centers of the holes Ha, Hb, Hc, and Hd coincide with the center of the component 120.

[0034] After step S4, the light source control unit 51 turns on the light source 31, and the camera control unit 50 causes the camera 2 to image the region A (step S5). At the time of this imaging, the other light sources 32, 33, and 34 are turned off.

[0035] After step S5, the light source control unit 51 turns on the light source 32, and the camera control unit 50 causes the camera 2 to image the region A (step S6). At the time of this imaging, the other light sources 31, 33, and 34 are turned off.

[0036] After step S6, the light source control unit 51 turns on the light source 33, and the camera control unit 50 causes the camera 2 to image the region A (step S7). At the time of this imaging, the other light sources 31, 32, and 34 are turned off.

[0037] After step S7, the light source control unit 51 turns on the light source 34, and the camera control unit 50 causes the camera 2 to image the region A (step S8). At the time of this imaging, the other light sources 31, 32, and 33 are turned off.

[0038] Subsequently, the analysis unit 53 determines whether or not the component 120 is normally inserted into the holes Ha, Hb, Hc, and Hd based on the image data obtained by the imaging in steps S5 to S8 (step S9).

[0039] As a result of the determination in step S9, if the component 120 is properly inserted into any of the holes Ha, Hb, Hc, and Hd (the "normal" case in step S9), the first process is executed (step S10). On the other hand, if the component 120 is not properly inserted into at least one of the holes Ha, Hb, Hc, and Hd (the "abnormal" case in step S9), the second process is executed (step S11). The series of operations ends with step S10 or step S11.

[0040] For example, the first process may include a process of notifying the operator that the assembly of the component 120 has been completed normally. Further, the first process may include a process of recording in the database that the assembly of the component 120 has been completed normally.

[0041] Similarly, the second process may include a process of notifying the operator that an abnormality has occurred in the assembly of the component 120. Further, the second process may include a process of recording in the database that an abnormality has occurred in the assembly of the component 120. Furthermore, the second process may include a process for eliminating the abnormality as described later.

[0042] Here, a specific example of a method for determining an abnormality in step S9 will be described. FIGS. 8 to 11 are diagrams showing examples of the image data IMG1 to IMG4 generated by the camera 2 in steps S5 to S8, respectively. Although it is rare for an insertion abnormality to actually occur, here, as an example, a case where an insertion abnormality has occurred in the holes Hb, Hc, and Hd in the manner shown in FIG. 5 is assumed.

[0043] For example, the image data IMG1 to IMG4 are obtained by binarizing grayscale or color multi-tone image data generated by the camera 2. Similar to the image data IMG0 shown in FIG. 7, the image data IMG1 to IMG4 include shadow portions P (Pa, Pb, Pc, Pd) corresponding to the holes Ha, Hb, Hc, and Hd. The cross marks in the image data IMG1 to IMG4 are the centers of the holes Ha, Hb, Hc, and Hd detected in step S3. In FIGS. 8 to 11, for the sake of convenience of explanation, a part of the shadow portions Pa, Pb, Pc, Pd that become black portions by binarization is shown by hatching.

[0044] In the image data IMG1 to IMG4, a shadow (the portion with dot hatching) of the component 120 is generated around the hole Ha into which the component 120 is normally inserted. Similarly, a shadow of the component 120 is also generated around the hole Hb where the insertion is insufficient but the component 120 protrudes upward. The shadow portions Pa, Pb include such shadows of the component 120 in addition to the shadows of the holes Ha, Hb.

[0045] The illumination directions D1 to D4 of the light sources 31 to 34 are different from each other. Therefore, the directions in which the shadow of the component 120 is generated around the holes Ha, Hb are different in each of the image data IMG1 to IMG4. Accordingly, the shapes of the shadow portions Pa, Pb are also different in the image data IMG1 to IMG4.

[0046] The shadow portion Pd of the hole Hd into which the component 120 is not inserted becomes an overall dark circular shadow in any of the image data IMG1 to IMG4. The shadow portion Pc of the hole Hc where the second portion 122 is missing and only the first portion 121 is inserted also becomes a circular shadow in each of the image data IMG1 to IMG4. However, since a little light is reflected at the first portion 121 inside the hole Hc, a slightly brighter portion (a portion that becomes white by binarization) may occur in the shadow portion Pc than in the shadow portion Pd.

[0047] The analysis unit 53 measures the length L1 (L1a, L1b, L1c, L1d) for each of the shadow portions Pa, Pb, Pc, Pd of the image data IMG1 shown in FIG. 8. The length L1a corresponds to the distance from the center of the hole Ha to the end of the shadow portion Pa in the illumination direction D1 (the X direction in FIG. 8). The length L1b corresponds to the distance from the center of the hole Hb to the end of the shadow portion Pb in the illumination direction D1. The length L1c corresponds to the distance from the center of the hole Hc to the end of the shadow portion Pc in the illumination direction D1. The length L1d corresponds to the distance from the center of the hole Hd to the end of the shadow portion Pd in the illumination direction D1.

[0048] Further, the analysis unit 53 measures the length L2 (L2a, L2b, L2c, L2d) for each of the shadow portions Pa, Pb, Pc, Pd of the image data IMG2 shown in FIG. 9. The length L2a corresponds to the distance from the center of the hole Ha to the end of the shadow portion Pa in the illumination direction D2 (the reverse direction of the X direction in FIG. 9). The length L2b corresponds to the distance from the center of the hole Hb to the end of the shadow portion Pb in the illumination direction D2. The length L2c corresponds to the distance from the center of the hole Hc to the end of the shadow portion Pc in the illumination direction D2. The length L2d corresponds to the distance from the center of the hole Hd to the end of the shadow portion Pd in the illumination direction D2.

[0049] Further, the analysis unit 53 measures the length L3 (L3a, L3b, L3c, L3d) for each of the shadow portions Pa, Pb, Pc, Pd of the image data IMG3 shown in FIG. 10. The length L3a corresponds to the distance from the center of the hole Ha to the end of the shadow portion Pa in the illumination direction D3 (the reverse direction of the Y direction in FIG. 10). The length L3b corresponds to the distance from the center of the hole Hb to the end of the shadow portion Pb in the illumination direction D3. The length L3c corresponds to the distance from the center of the hole Hc to the end of the shadow portion Pc in the illumination direction D3. The length L3d corresponds to the distance from the center of the hole Hd to the end of the shadow portion Pd in the illumination direction D3.

[0050] Further, the analysis unit 53 measures the lengths L4 (L4a, L4b, L4c, L4d) for the shadow portions Pa, Pb, Pc, Pd of the image data IMG4 shown in FIG. 11. The length L4a corresponds to the distance from the center of the hole Ha to the end of the shadow portion Pa in the illumination direction D4 (Y direction in FIG. 10). The length L4b corresponds to the distance from the center of the hole Hb to the end of the shadow portion Pb in the illumination direction D4. The length L4c corresponds to the distance from the center of the hole Hc to the end of the shadow portion Pc in the illumination direction D4. The length L4d corresponds to the distance from the center of the hole Hd to the end of the shadow portion Pd in the illumination direction D4.

[0051] In the examples of FIGS. 8 to 11, the lengths L1a to L4a correspond to the length of the shadow of the component 120 inserted into the hole Ha. Also, the lengths L1b to L4b correspond to the length of the shadow of the component 120 inserted into the hole Hb.

[0052] In the present embodiment, the analysis unit 53 determines whether the insertion of the component 120 into the hole H is normal based on at least the lengths L1, L2, L3, and L4.

[0053] The abnormalities determined by the analysis unit 53 include, for example, the following NG modes. NG mode 1: A state where the component 120 is not inserted into the hole H. NG mode 2: A state where the component 120 protrudes slightly straight from the hole H more than in the normal state. NG mode 3: A state where the component 120 protrudes significantly straight from the hole H more than in the normal state. NG mode 4: A state where the component 120 protrudes slightly inclined from the hole H more than in the normal state. NG mode 5: A state where the component 120 protrudes significantly inclined from the hole H more than in the normal state. NG mode 6: A state where an incomplete component 120 with the second portion 122 missing is inserted into the hole H.

[0054] Hereinafter, an example of the determination method for NG modes 1 to 6 will be described. In NG modes 1 and 6, the lengths L1 to L4 are all equal to the radius of the hole H. Therefore, when determining NG modes 1 and 6, the analysis unit 53 determines whether the lengths L1 to L4 are all equal to or less than a threshold value SH1. This threshold value SH1 is set to a value that allows the part 120 to be regarded as not inserted into the hole H, for example, a value slightly larger than the radius of the hole H.

[0055] When the lengths L1 to L4 are all equal to or less than the threshold value SH1, the analysis unit 53 also refers to the shadow portion P of the hole H in the image data IMG1 to IMG4. For example, if the portion corresponding to the hole H is dark overall like the shadow portion Pd in FIGS. 8 to 11, it can be considered that the part 120 is not inserted into the hole H, so it can be determined that it is in NG mode 1. On the other hand, if the portion corresponding to the hole H includes a slightly brighter area like the shadow portion Pc, it can be considered that an incomplete part 120 is inserted into the hole H, so it can be determined that it is in NG mode 6.

[0056] In NG modes 2 to 5, the insertion of the part 120 into the hole H is incomplete in all cases. When determining NG modes 2 to 5, the analysis unit 53 determines whether the difference in the lengths L1 to L4 (the difference in the lengths of the shadows of the part 120) is equal to or greater than a threshold value SH2. As the "difference" here, for example, the difference between the maximum value and the minimum value of the lengths L1 to L4 can be used. For example, if the part 120 is inserted straight into the hole H, the lengths L1 to L4 are substantially equal, so the above difference is also substantially zero. On the other hand, when the part 120 is inserted into the hole H obliquely, at least a part of the lengths L1 to L4 is different, and thus the above difference is not zero. The threshold value SH2 separates the state where the part 120 is inserted obliquely in this way from the state where it is inserted straight.

[0057] In addition, the analysis unit 53 determines whether the lengths L1 to L4 are equal to or greater than a threshold value SH3. The threshold value SH3 separates the state where the part 120 is inserted normally like the hole Ha shown in FIG. 5 from the state where it is inserted floating from the bottom of the hole H.

[0058] Furthermore, when the lengths L1 to L4 are equal to or greater than the threshold value SH3, the analysis unit 53 determines whether the lengths L1 to L4 are equal to or greater than the threshold value SH4. The threshold value SH4 is a value greater than the threshold value SH3, and separates a state where the component 120 protrudes slightly more than the normal state from a state where it protrudes significantly. Note that, for comparison with the threshold values SH3 and SH4, for example, the maximum value, minimum value, or average value of the lengths L1 to L4 can be used.

[0059] As a result of the above determination, when the difference between the lengths L1 to L4 is less than the threshold value SH2, and the lengths L1 to L4 are equal to or greater than the threshold value SH3 and less than the threshold value SH4, it can be determined that it is the NG mode 2. Also, when the difference between the lengths L1 to L4 is less than the threshold value SH2, and the lengths L1 to L4 are equal to or greater than the threshold value SH4, it can be determined that it is the NG mode 3. Also, when the difference between the lengths L1 to L4 is equal to or greater than the threshold value SH2, and the lengths L1 to L4 are equal to or greater than the threshold value SH3 and less than the threshold value SH4, it can be determined that it is the NG mode 4. Also, when the difference between the lengths L1 to L4 is equal to or greater than the threshold value SH2, and the lengths L1 to L4 are equal to or greater than the threshold value SH4, it can be determined that it is the NG mode 5.

[0060] In step S9, by the method as described above, it is determined whether each of the holes Ha, Hb, Hc, and Hd corresponds to any of the NG modes 1 to 6. In the examples of FIGS. 5, 8 to 11, it is determined that the hole Hb is either in the NG mode 4 or 5, the hole Hc is in the NG mode 6, and the hole Hd is in the NG mode 1. Also, since the hole Ha does not correspond to any of the NG modes 1 to 6, it is determined that the component 120 is assembled normally.

[0061] As described above, the second process in step S11 may include a process for eliminating an abnormality. For example, when an abnormality in the NG mode 1 occurs, the assembling device 6 may retry inserting the component 120 with respect to the hole H in which the abnormality has occurred.

[0062] Further, when an abnormality occurs in NG modes 2 to 4, a process of pushing the component 120 into the hole H where the abnormality has occurred may be performed. Such a process may be performed by the assembling device 6, may be performed by another device, or may be performed manually.

[0063] Further, when an abnormality occurs in NG modes 2 to 4, 5, a screen indicating the hole H where the abnormality has occurred may be displayed on the display or the like of the controller 5. On the screen, for example, it is preferable that the hole among Ha, Hb, Hc, and Hd where the abnormality has occurred can be visually discriminated. Further, the screen may include a message prompting the operator to make a manual correction.

[0064] Further, when an abnormality occurs in NG modes 2 to 6, the component 120 may be removed from the hole H where the abnormality has occurred. Such a process may be performed by the assembling device 6, may be performed by another device, or may be performed manually. After the component 120 is removed in this way, the process may return to step S4, the component 120 may be inserted into the hole H again, and the operations after step S5 may be performed again.

[0065] In the above-described embodiment, when inspecting the object 100, the light sources 31 to 34 are sequentially turned on, and the area A including the holes H (Ha, Hb, Hc, Hd) is imaged by the camera 2. Further, based on the shadow portions P (Pa, Pb, Pc, Pd) included in the image data IMG1 to IMG4 generated by this imaging, it is determined whether the component 120 is normally inserted into the hole H.

[0066] With such a configuration, the detection accuracy of abnormalities can be improved compared to the case of making a determination based on an image illuminated from one direction. Specifically, in a state where the component 120 is inserted obliquely like in NG modes 4 and 5, it is difficult to detect based only on the shadow part in the image illuminated from one direction. Specifically, when the component 120 is tilted so as to face the direction of the light source, even if the component 120 protrudes from the hole H more than in the normal state, a shadow part having the same shape as in the normal state may occur. In this case, there is a possibility that it may be determined as normal even though the component 120 is tilted.

[0067] On the other hand, when using a plurality of image data IMG1 to IMG4 captured by illuminating from different directions as in the present embodiment, it is possible to detect abnormalities such as NG modes 4 and 5.

[0068] Also, in the present embodiment, it may be determined whether the first part 121 and the second part 122 of the component 120 are inserted into the hole H in a state where they are normally connected (a state not corresponding to NG mode 6). As a result, it becomes possible to perform an inspection that also takes into account abnormalities in the component 120 itself composed of a plurality of parts.

[0069] The configuration disclosed in the present embodiment can be deformed in various ways. For example, the relationship between the light sources 31 to 34 and the holes Ha, Hb, Hc, Hd is not limited to that shown in FIG. 2.

[0070] FIG. 12 is a schematic plan view showing a modification of the relationship between the light sources 31 to 34 and the holes Ha, Hb, Hc, Hd. In this modification, the arrangement direction Dr of the holes Ha, Hb, Hc, Hd intersects the illumination directions D1 to D4 in a plan view.

[0071] With such a configuration, the shadow of the component 120 generated when each of the light sources 31 to 34 is lit is less likely to overlap with the other holes H near the hole H into which the component 120 is inserted. Therefore, the accuracy of abnormality detection can be further improved.

[0072] The inspection device 1 does not necessarily need to include four light sources 31 to 34. For example, if the inspection device 1 includes at least two light sources, it is possible to detect a state in which the component 120 is inclined, such as in the NG modes 4 and 5, based on the length of the shadow of the component 120.

[0073] In the present embodiment, a case where the component 120 includes a cylindrical first portion 121 and a cylindrical second portion 122 is assumed, but the configuration of the component 120 is not limited to this example. The component 120 may include three or more decomposable parts. Further, each part of the component 120 may have another shape, such as a block shape, for example. Also, the component 120 may be non-decomposable. The shape of the hole H is not limited to that shown in each figure.

[0074] The object 100 to be inspected is not particularly limited. The inspection device 1 and the inspection method disclosed in the present embodiment can be widely applied to a structure in which a component is inserted into a hole.

[0075] The illumination directions D1 to D4 of the light sources 31 to 34 do not necessarily need to be inclined at the same angle with respect to the assembly surface 111. That is, at least one of the angles θ1 to θ4 shown in FIGS. 3 and 4 may be different from the other angles.

[0076] The image data IMG0 to IMG4 do not necessarily need to be binarized data. For example, in step S3, the analysis unit 53 may detect the positions of the holes Ha, Hb, Hc, and Hd based on the image data IMG0, which is grayscale or color multi-tone image data generated by the camera 2. Also, in step S9, the analysis unit 53 may detect the shadow portions Pa, Pb, Pc, and Pd based on the image data IMG1 to IMG4, which is grayscale or color multi-tone image data generated by the camera 2.

Explanation of Reference Numerals

[0077] 1... inspection device, 2... camera, 31 - 34... light sources, 4... moving mechanism, 5... controller, 6... assembling device, 50... camera control unit, 51... light source control unit, 52... movement control unit, 53... analysis unit, 100... object, 110... base member, 120... component, 121... first part, 122... second part.

Claims

1. An inspection apparatus for an object including a hole and a component inserted into the hole, a plurality of light sources that sequentially illuminate a region including the hole from different directions, a camera that generates a plurality of image data of the region sequentially illuminated by the plurality of light sources, a controller that determines whether the component is normally inserted into the hole based on the shadows included in each of the plurality of image data generated by the camera, and an inspection apparatus comprising the same.

2. The controller determines whether the component is normally inserted into the hole based on the length of the shadow of the component included in each of the plurality of image data. The inspection apparatus according to claim 1.

3. The controller determines whether the component is normally inserted into the hole by comparing the difference in the length of the shadow of the component included in at least two of the plurality of image data with a threshold value. The inspection apparatus according to claim 2.

4. The component includes a first part and a second part that can be disassembled from each other. The controller further determines whether the first part and the second part are inserted into the hole in a normally connected state based on the plurality of image data. The inspection apparatus according to claim 1.

5. The directions in which the plurality of light sources emit light are inclined at the same angle with respect to the surface of the object on which the hole is provided. The inspection apparatus according to claim 1.

6. The object has a plurality of the holes arranged linearly. The directions in which the plurality of light sources emit light intersect the arrangement direction of the plurality of holes in a plan view. The inspection apparatus according to claim 1.

7. An inspection method for an object including a hole and a component inserted into the hole, sequentially illuminating the area including the hole from different directions with a plurality of light sources, generating a plurality of image data of the area sequentially illuminated by the plurality of light sources with a camera, and determining whether the component is normally inserted into the hole based on the shadows included in each of the plurality of image data generated by the camera. The inspection method includes the above.

8. The determination includes determining whether the component is normally inserted into the hole based on the length of the shadow of the component included in each of the plurality of image data. The inspection method according to claim 7.

9. The determination includes determining whether the component is normally inserted into the hole by comparing the difference in the length of the shadow of the component included in at least two of the plurality of image data with a threshold value. The inspection method according to claim 8.

10. The component includes a first part and a second part that can be disassembled from each other, and the determination includes determining whether the first part and the second part are inserted into the hole in a normally connected state based on the plurality of image data. The inspection method according to claim 7.

11. The directions in which the plurality of light sources emit light are inclined at the same angle with respect to the surface of the object where the hole is provided. The inspection method according to claim 7.

12. The object has a plurality of the holes arranged linearly, and the directions in which the plurality of light sources emit light intersect the arrangement direction of the plurality of holes in a plan view. The inspection method according to claim 7.

Images