Surface inspection device
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2026-01-19
- Publication Date
- 2026-08-13
Smart Images
Figure JP2026001551_13082026_PF_FP_ABST
Abstract
Description
Surface inspection device
[0001] The present invention relates to a surface inspection device for inspecting the surface of an inspection object.
[0002] Patent Document 1 discloses a surface roughness measurement method. The surface roughness measurement method irradiates parallel light perpendicularly to the object to be measured, forms an image of the reflected light from the object to be measured with an optical lens, obtains the standard deviation of the luminance histogram of the reflected light image, and measures the surface roughness of the object to be measured based on the standard deviation. When parallel light is irradiated perpendicularly to the object to be measured, the parallel light is specularly reflected on the surface of the object to be measured. The direction of the reflected light varies depending on the irregularities formed on the surface. The reflected light is imaged on the imaging surface by an optical lens. Where the inclination angle of the irregularities is large and the reflected light does not enter the aperture of the lens, it appears dark. Where the inclination angle is almost zero and the reflected light enters the lens, it appears bright.
[0003] Non-Patent Document 1 discloses an event-based vision sensor (EVS). The EVS is a vision sensor that seamlessly captures "motion" with high temporal resolution.
[0004] Non-Patent Document 2 discloses an event-based vision sensor (EVS) technology. The EVS detects the luminance change of each pixel and outputs only the changed data in combination with "coordinate" and "time information" to achieve high-speed and low-latency data output. In the EVS, the incident light is converted into an electrical signal by the light-receiving circuit of the sensor. Further, the electrical signal is separated by a comparator through an amplifier according to the luminance change, becoming a light-on signal (positive event) and a light-off signal (negative event), and is output as EVS image data through subsequent signal processing. The EVS detects, as an event, when the luminance change of the light captured for each pixel exceeds a set threshold value, and outputs the coordinates, time, and polarity of the pixel where the event occurred. This operation is performed independently and asynchronously for each pixel.
[0005] Non-Patent Documents 3 and 4 disclose cameras equipped with an event-based vision sensor.
[0006] Japanese Patent Application Laid-Open No. 59-7980804
[0007] Sony Semiconductor Solutions Corporation, “Event-Based Vision Sensor (EVS)”, [online], [Retrieved January 18, 2025], Internet <URL: https: / / www.sony-semicon.com / ja / products / is / industry / evs.html> Sony Semiconductor Solutions Corporation, “Event-Based Vision Sensor (EVS) Technology”, [online], [Retrieved January 19, 2025], Internet <URL: https: / / www.sony-semicon.com / ja / technology / industry / evs.html> PROPHESEE, “EVALUATION KITS”, [online], [Retrieved January 18, 2025], Internet <URL: https: / / www.prophesee.ai / event-based-evaluation-kits / > PROPHESEE, “EVK4 HD, [online], [searched January 27, 2025], Internet <URL: https: / / www.prophesee.ai / event-camera-evk4 / >
[0008] The surface of a product or part is formed by machining the material. Examples of this machining include cutting, forging, and casting. Part or all of the surface formed by machining may be further machined to meet design-specified tolerances. Examples of this machining include cutting, grinding, and polishing. For example, a surface formed by cutting may then be ground or polished. An example of polishing is buffing. Examples of tolerances include surface roughness and flatness.
[0009] In manufacturing, it is necessary to produce multiple identical products or parts with consistent quality. However, machining makes it impossible or extremely difficult to achieve identical surface finishes for products or parts, resulting in variations between individual products or parts. In manufacturing, the surface of products or parts is sometimes visually inspected by skilled workers. In this visual inspection, even if the surface of a product or part is finished to the tolerance specified in the design, it may be judged as "defective." After various studies, the inventor realized that the judgment result of the visual inspection of the surface of a product or part is related to the reflection of light on the surface of the product or part.
[0010] The present invention aims to provide a novel surface inspection device that enables the inspection of the surface of a product or component.
[0011] One aspect of the present invention is a surface inspection device comprising: an installation device including a fixture on which an object to be inspected is placed; an imaging device for imaging the inspection surface of the object to be inspected, which is provided on the installation device; and a support device for supporting the imaging device, wherein the installation device includes a vibration generator for vibrating the installation device; the imaging device includes an event-based vision sensor; the support device is positioned such that the imaging device is on the first side of the first direction relative to the installation device, and the imaging device is positioned opposite the installation device in the first direction; and the vibration generator vibrates the installation device when the imaging device images the inspection surface.
[0012] This surface inspection device allows the object being inspected to vibrate along with the mounting fixture by vibrating the fixture itself. The device can create brightness changes on the inspection surface by vibrating the object. An event-based vision sensor detects brightness changes at each pixel and outputs this information in combination with coordinate and time data. This allows for a "good" or "bad" judgment based on the areas where brightness changes occur. For example, even if the surface of a product or part is finished to the tolerance specified in the design, areas with brightness changes can be detected as defects, resulting in a "bad" judgment.
[0013] The vibration generator may be configured to vibrate the mounting device in the first direction.
[0014] With this configuration, when photographing the inspection surface with the imaging device, the relative positions of the inspection surface in the second and third directions with respect to the imaging device can be kept constant. The second and third directions are perpendicular to the first direction. The third direction is perpendicular to the second direction.
[0015] The fixture includes an illumination device that irradiates illumination light onto the inspection surface of the object to be inspected, and the illumination device may be configured to irradiate the inspection surface with illumination light when the imaging device photographs the inspection surface.
[0016] With this configuration, by shining illumination light onto the inspection surface while the object being inspected is vibrating, the illumination light can be diffusely reflected by the inspection surface. This makes it possible to clearly see the change in brightness.
[0017] According to the present invention, a new surface inspection device can be obtained that enables the inspection of the surface of a product or part.
[0018] This is a perspective view showing an example of a surface inspection device. The perspective view shows the front, top, and right side of the surface inspection device. This shows the state after the installation operation of the object to be inspected on the surface inspection device has been completed. This is a front view of the surface inspection device. This is a perspective view showing an example of the first step of the installation operation of the object to be inspected on the surface inspection device. This is a perspective view showing an example of the second step of the installation operation of the object to be inspected on the surface inspection device. This is a perspective view showing an example of an object to be inspected. This is a cross-sectional view taken along line A-A in Figure 5. This figure shows an example of an image captured by the imaging device of the surface inspection device. The upper row shows an image captured using the surface of an object to be inspected as the inspection surface, where the result of the visual inspection by the worker is judged as "good". The lower row shows an image captured using the surface of an object to be inspected as the inspection surface, where the result of the visual inspection by the worker is judged as "bad".
[0019] Embodiments for carrying out the present invention will be described with reference to the drawings. The present invention is not limited to the configurations described below, and various configurations can be adopted within the same technical concept. For example, some of the configurations shown below may be omitted or replaced with other configurations. The present invention may include other configurations. The drawings are explanatory diagrams for understanding the present invention. Each drawing may not correspond accurately to other drawings. Hatching indicates a cross-section.
[0020] <Surface Inspection Device 10> The surface inspection device 10 will be described with reference to Figures 1 to 7. In this embodiment, the "first direction," "second direction," and "third direction" are used as directions to specify the surface inspection device 10 (see Figures 1 to 4). The second and third directions are perpendicular to the first direction. The third direction is perpendicular to the second direction. One side of the first direction is called the "first side," and the other side of the first direction is called the "second side." The first direction is the vertical direction, and the second and third directions are the horizontal directions. The first side of the first direction is the upper side in the vertical direction, and the second side of the first direction is the lower side in the vertical direction.
[0021] The surface inspection device 10 is used to inspect the surface of the object to be inspected 60 (see Figures 1-4). In this embodiment, the surface of the object to be inspected 60 is called the "inspection surface 61" (see Figures 5 and 6). Examples of the object to be inspected 60 include products or parts (see Figures 1-6). Products or parts are formed by machining materials. Examples of this machining include cutting, forging, and casting. Part or all of the surface formed by machining may be subjected to further machining to finish to tolerances specified in the design. Examples of this machining include cutting, grinding, and polishing. In the production site, the surface of the object to be inspected 60, which has been finished to tolerances specified in the design by skilled workers, may be visually inspected as the inspection surface 61. The surface inspection device 10 can be used for inspection of the surface of the object to be inspected 60, which has been finished to tolerances specified in the design, as the inspection surface 61.
[0022] In this embodiment, the object to be inspected 60 is a machined part having a recess with a stepped inner surface, and the inspection surface 61 is an annular plane that forms the intermediate step of this recess (see Figures 5 and 6). This recess is provided on the first side surface of the object to be inspected 60 in the first direction when the object to be inspected 60 is placed on the surface inspection device 10 described later, and furthermore, in the above state, the first direction is the depth direction (see Figures 1 to 6). Examples of materials used to form the machined part include metals and resins. For example, in machined parts, cutting and polishing are used to form the recess with a stepped inner surface. An example of polishing is buffing. For example, the annular plane that forms the step on the inner surface of this recess is finished to a tolerance specified in the design by buffing after cutting. Examples of tolerances include surface roughness and flatness.
[0023] The shape of the object to be inspected 60 and the shape of the inspection surface 61 are illustrative examples. The object to be inspected may have a different shape from the object to be inspected 60. The object to be inspected does not have to include recesses. The object to be inspected may include convex parts, or may include both recesses and convex parts. The object to be inspected may be a sphere, an ellipsoid, a columnar body, a cylindrical body, or a conical body. The inspection surface may have a different shape from the inspection surface 61. The inspection surface may be an inclined surface or a curved surface. Examples of inclined surfaces include inclined planes and inclined curved surfaces. A curved surface has a predetermined curvature. Examples of curved surfaces include cylindrical surfaces, cylindrical faces, curved surfaces, and arc-shaped surfaces. The curved surfaces that form an inclined curved surface are the same as these. The shape of the object to be inspected and the shape of the inspection surface are determined appropriately considering various conditions.
[0024] The surface inspection device 10 includes an installation device 20, a photography device 30, a support device 40, and a lighting device 50 (see Figures 1-4). The installation device 20 includes an installation fixture 21 and a vibration generator 28. The installation fixture 21 is provided with an object to be inspected 60. In this embodiment, the installation fixture 21 includes a housing 22 and a lid 24. The housing 22 has a housing chamber 23, and houses the object to be inspected 60 in the housing chamber 23 (see Figures 2-4). When performing an inspection with the surface inspection device 10, the operator houses the object to be inspected 60 in the housing chamber 23 (see Figures 3-4). Subsequently, the operator attaches the lid 24 to the first side of the housing 22 in the first direction (see Figures 4-1,2). With the object to be inspected 60 housed in the housing chamber 23, the second and third position of the object to be inspected on the installation fixture 21 are fixed, respectively. Furthermore, when the lid 24 is attached to the container 22, the position of the object to be inspected 60 in the first direction on the mounting device 21 is fixed.
[0025] In the mounting device 21, the lid 24 is positioned relative to the container 22 and is provided on the first end face of the container 22 in the first direction (see Figures 1 and 2). The mounting device 21 employs the fitting of positioning pins 25 and positioning holes 26 for this positioning (see Figures 1, 3, and 4). Specifically, the container 22 is provided with two positioning pins 25 on the first end face in the first direction, and the lid 24 is provided with two positioning holes 26. The positioning holes 26 penetrate the lid 24 in the first direction. However, this positioning structure in the mounting device 21 is illustrative. The positioning structure of the container 22 and the lid 24 is determined appropriately considering various conditions. The lid 24 is provided with an imaging hole 27. The imaging hole 27 penetrates the lid 24 in the first direction. The inspection surface 61 is exposed to the first side in the first direction through the imaging hole 27 when the object to be inspected 60 is provided in the mounting device 21.
[0026] The vibration generator 28 vibrates the mounting fixture 21 (see Figures 1 and 2). The mounting fixture 21 is installed on the vibration generator 28 in the following state. In this state, the second and third positions of the mounting fixture 21 relative to the vibration generator 28 are positioned, respectively. Accordingly, the object to be inspected 60 is installed on the mounting device 20 with its second and third positions fixed. The inspection surface 61 is parallel to the mounting surface 29 of the vibration generator 28. However, the mounting surface 29 is based on the state in which the vibration generator 28 is stationary. The mounting fixture 21 is placed on the mounting surface 29. In this embodiment, the mounting surface 29 is set horizontally when the vibration generator 28 is stationary.
[0027] The vibration generator 28 may be set to a frequency in the range of 10 to 300 Hz, and to an acceleration in the range of 0.1 to 2.0 G. In experiments conducted by the inventor, a preferred setting for the frequency was 30 Hz, and a preferred setting for the acceleration was 0.9 G. However, these setting values for frequency and acceleration are examples only. The frequency and acceleration are determined appropriately considering various conditions. An example of the aforementioned conditions is the change in brightness on the inspection surface 61. In the surface inspection device 10, a known vibration generator can be used as the vibration generator 28. Therefore, further explanation regarding the vibration generator 28 is omitted.
[0028] The imaging device 30 photographs the inspection surface 61 of the object to be inspected 60, which is mounted on the fixture 21 (see Figures 1, 2, and 7). The imaging device 30 includes an event-based vision sensor. The imaging device 30 includes a camera body 31 and a lens 32 (see Figures 1 to 4). In the imaging device 30, the camera body 31 can be the "Metavision® EVK4 - HD" camera manufactured by PROPHESEE, as described in Non-Patent Documents 3 and 4 mentioned above. The camera body 31 in Non-Patent Documents 3 and 4 includes an event-based vision sensor "IMX636 (1280×720px)". That is, the imaging device 30 includes an event-based vision sensor in the camera body 31.
[0029] In the imaging device 30, a known optical system can be used as the lens 32. The lens 32 may be a telecentric optical system. By using a telecentric optical system for the lens 32, the inspection surface 61 can be photographed at a constant size while suppressing distortion. The imaging device 30 employs a double-sided telecentric optical system for the lens 32. However, the lens 32 does not have to be a double-sided telecentric optical system. The lens 32 may be a single-sided telecentric optical system. The optical system of the imaging device 30 is determined appropriately considering various conditions. The camera body 31 and the lens 32 are already in practical use and are publicly known. Therefore, further explanation regarding the imaging device 30 is omitted. In this embodiment, the direction in which the imaging device 30 takes photographs is called the "imaging direction" (see Figure 2). In this embodiment, the imaging direction coincides with the first side to the second side of the first direction.
[0030] The support device 40 supports the imaging device 30 (see Figures 1-4). The support device 40 positions the imaging device 30 as the first side in the first direction relative to the mounting fixture 21. The surface inspection device 10 employs a vertical articulated robot as the support device 40. Vertical articulated robots are already in practical use and are well known. Therefore, a description of the structure of the support device 40 will be omitted. The support device 40 includes a fixing jig 41. The support device 40 supports the imaging device 30 via the fixing jig 41. When the support device 40 is a vertical articulated robot, the fixing jig 41 is attached to the tip of the robot arm, and the imaging device 30 is fixed to the fixing jig 41.
[0031] The support device 40 adjusts the posture of the imaging device 30 and supports the imaging device 30 in the adjusted posture. In this embodiment, the support device 40 aligns the imaging direction of the imaging device 30 from the first side to the second side of the first direction (see Figure 2). The fixing jig 41 has a reference plane 42. The reference plane 42 has a constant relationship with the imaging direction when fixed. When fixed, the imaging device 30 is fixed to the fixing jig 41 (see Figures 1 to 4). In this embodiment, the reference plane 42 has a perpendicular relationship with the imaging direction when fixed (see Figure 2). In the support device 40, a vertical articulated robot is driven to adjust the reference plane 42 to the following state. In this state, the reference plane 42 is set horizontally. In this case, the reference plane 42 is set parallel to the horizontal mounting surface 29 of the vibration generator 28.
[0032] The horizontality of the reference plane 42 may be confirmed using a spirit level. In this embodiment, the spirit level includes a measuring instrument called a level. Spirit levels are already in practical use and are well known. Therefore, further explanation regarding spirit levels is omitted. Preferably, the reference plane 42 is an area where the spirit level used for this adjustment can be installed.
[0033] In the surface inspection apparatus 10, the support device 40 positions the imaging device 30 facing the mounting fixture 21 in the first direction, with the imaging device 30 facing the mounting fixture 21 in the first direction (see Figures 1 and 2). In this embodiment, the imaging device 30 faces the inspection surface 61 of the object to be inspected 60, which is provided on the mounting fixture 21 on the vibration generator 28, in the first direction. In this embodiment, "mounting fixture 21 on the vibration generator 28" can also be described as "mounting fixture 21 placed on the mounting surface 29 of the vibration generator 28".
[0034] In the surface inspection device 10, the vibration generator 28 vibrates the mounting fixture 21 when the imaging device 30 is imaging the inspection surface 61 (see Figures 1 and 2). The vibration generator 28 vibrates the mounting fixture 21 in a first direction. By vibrating the mounting fixture 21 in a first direction, the vibration generator 28 causes the object to be inspected 60, which is attached to the mounting fixture 21, to vibrate in a first direction. The imaging device 30, by causing the object to be inspected 60 to vibrate in a first direction, images the inspection surface 61 vibrating in a first direction from the first side in that first direction.
[0035] The lighting device 50 illuminates the inspection surface 61 with illumination light when the imaging device 30 is imaging the inspection surface 61. An example of the light source for the lighting device 50 is an LED light source. An example of the illumination light is white diffused light. However, the light source for the lighting device 50 may be different from an LED light source. The illumination light may be different from white diffused light. In the lighting device 50, the light source and illumination light are appropriately determined considering various conditions. The lighting device 50 is installed on the first side in the first direction from the mounting fixture 21 and on the second side in the first direction from the imaging device 30. The surface inspection device 10 employs ring illumination as the lighting device 50. By using ring illumination for the lighting device 50, the lighting device 50 can illuminate the inspection surface 61 without obstructing the imaging device 30.
[0036] In the surface inspection apparatus 10, the illumination device 50 is mounted on the support device 40. The illumination device 50 is mounted on the support device 40 so that its position in the following direction can be adjusted. This direction coincides with the first direction when the imaging device 30 and the mounting fixture 21 are arranged facing each other in the first direction. The following adjustment mechanism can be used for this adjustment. An example of this adjustment mechanism is a combination of a shaft and a collar. In this case, the shaft is fixed to the support device 40, the collar is fixed to the shaft, and the illumination device 50 is fixed to the collar. By changing the fixing position of the collar relative to the shaft, the position of the illumination device 50 in the first direction is adjusted.
[0037] <Effects of the Embodiment> According to the embodiment, the following effects can be obtained.
[0038] (1) The surface inspection device 10 includes an installation device 20, an imaging device 30, and a support device 40 (see Figures 1 to 4). The installation device 20 includes an installation fixture 21. An object to be inspected 60 is provided on the installation fixture 21 (see Figures 1 to 4). The imaging device 30 photographs the inspection surface 61 of the object to be inspected 60 provided on the installation fixture 21 (see Figures 1, 2, and 7). The support device 40 supports the imaging device 30 (see Figures 1 to 4). The installation device 20 includes a vibration generator 28. The vibration generator 28 vibrates the installation fixture 21 (see Figures 1 and 2). The imaging device 30 includes an event-based vision sensor. The event-based vision sensor includes multiple pixels. The event-based vision sensor detects changes in brightness of each pixel and outputs only the changed data in combination with "coordinates" and "time information" (see Non-Patent Literature 2 mentioned above). The support device 40 positions the imaging device 30 facing the mounting fixture 21 in the first direction, with the imaging device 30 facing the mounting fixture 21 in the first direction (see Figures 1 and 2). The vibration generator 28 vibrates the mounting fixture 21 when the imaging device 30 is imaging the inspection surface 61 (see Figures 1 and 2).
[0039] The surface inspection device 10 can vibrate the inspection object 60 together with the mounting fixture 21 by vibrating the fixture 21 on which the inspection object 60 is mounted. The surface inspection device 10 can cause a change in brightness on the inspection surface 61 by vibrating the inspection object 60. An event-based vision sensor can detect the brightness change of each pixel and output this in combination with coordinate and time information. It is possible to make a judgment of "good" or "bad" depending on the area where the brightness change is occurring. For example, even if the surface of a product or part is finished to the tolerance specified in the design, it is possible to detect the area where the brightness change is occurring as a defect and make a judgment of "bad". This makes it possible to inspect the surface of a product or part without relying on skilled workers to make such judgments.
[0040] The inventor conducted an experiment to confirm the effectiveness of the surface inspection device 10. The experiment used a surface inspection device equivalent to the surface inspection device 10. In the description of this experiment, in order to clarify the correspondence with the embodiments described above, the reference numerals for each part of the same or corresponding elements will be the same as above. The surface inspection device 10 includes a camera "Metavision® EVK4 - HD" manufactured by PROPHESEE, as described in Non-Patent Documents 3 and 4, as the imaging device 30. The vibration generator 28 was set to a frequency of 30 Hz and an acceleration of 0.9 G. The surface of the object to be inspected 60, which was used as the inspection surface 61, was buffed and finished to tolerances specified in the design. Examples of tolerances specified in the design include surface roughness and flatness. The inspection surface 61 to be photographed was the surface of the object to be inspected 60 that was judged as "good" by a skilled worker's visual inspection, and the surface of the object to be inspected 60 that was judged as "poor" by the same visual inspection.
[0041] In the experiment, a different object 60 was used as the sample for inspection than that shown in Figures 1-6. Therefore, the inspection surface 61 photographed in the experiment has a different shape from the inspection surface 61 in Figures 1-6. In the upper and lower images of Figure 7, the following boundary line is superimposed on the outer edge of the inspection surface 61, and the inspection surface 61 is clearly visible in these images. This boundary line has the appearance of a thick white solid line superimposed with a thinner black dashed line.
[0042] As a result of the experiment, in the captured image of the surface of the inspection object 60 whose determination result is "defective" (see the lower part of FIG. 7), compared with the captured image of the surface of the inspection object 60 whose determination result is "good" (see the upper part of FIG. 7), many pixels that cause luminance changes with vibration (see the "pixels shown in black" within the inspection surface 61) can be observed on the inspection surface 61.
[0043] Although detailed description is omitted, by executing image analysis with the captured image as the processing target by a computer, it is possible to determine whether the inspection surface 61 is "good" or "defective". For example, by specifying the pixels that cause luminance changes and comparing the total amount of the pixels that cause luminance changes with a predetermined reference value, it is possible to determine whether the inspection surface 61 is "good" or "defective". However, such determination of whether the inspection surface 61 is "good" or "defective" is an example. The determination of whether the inspection surface 61 is "good" or "defective" may be executed by different image analysis processes from the above. Known image analysis processes can be applied to the determination of whether the inspection surface 61 is "good" or "defective". Image analysis processes using known artificial intelligence may also be adopted for the determination of whether the inspection surface 61 is "good" or "defective". Therefore, other explanations regarding the determination of whether the inspection surface 61 is "good" or "defective" are omitted.
[0044] (2) The vibration generator 28 vibrates the fixture 21 in the first direction (see FIGS. 1 and 2). According to this configuration, when the inspection surface 61 is photographed by the photographing device 30, the relative positions of the inspection surface 61 with respect to the photographing device 30 in the second direction and the third direction can be made constant.
[0045] (3) The surface inspection device 10 includes a lighting device 50. The lighting device 50 irradiates illumination light onto the inspection surface 61 of the inspection object 60 provided on the fixture 21. The lighting device 50 irradiates illumination light onto the inspection surface 61 when the photographing device 30 photographs the inspection surface 61. According to this configuration, by irradiating the illumination light onto the inspection surface 61 while the inspection object 60 is vibrating, the illumination light can be diffusely reflected by the inspection surface 61. The luminance change can be made clear.
[0046] (4) The surface inspection device 10 can also be specified as follows, and can realize the functions and effects described above. That is, the surface inspection device 10 includes an installation device 20, an imaging device 30, a support device 40, and an illumination device 50 (see Figures 1 to 4). The installation device 20 includes an installation fixture 21. An object to be inspected 60 is provided on the installation fixture 21. The imaging device 30 photographs the inspection surface 61 of the object to be inspected 60 provided on the installation fixture 21 (see Figures 1, 2, and 7). The support device 40 supports the imaging device 30 (see Figures 1 to 4). The illumination device 50 irradiates illumination light onto the inspection surface 61 of the object to be inspected 60 provided on the installation fixture 21. The illumination light is white diffuse light. The installation device 20 includes a vibration generator 28. The vibration generator 28 vibrates the installation fixture 21 in a first direction (see Figures 1 and 2). The imaging device 30 includes an event-based vision sensor. The support device 40 includes a fixing jig 41 (see Figures 1-4). The fixing jig 41 fixes the imaging device 30. In the fixed state, the support device 40 supports the imaging device 30 via the fixing jig 41. In the fixed state, the imaging device 30 is fixed to the fixing jig 41. The fixing jig 41 includes a reference plane 42. In the fixed state, the reference plane 42 has a certain relationship with the imaging direction of the imaging device 30. The support device 40 positions the imaging device 30 opposite the mounting fixture 21 in the first direction with respect to the mounting fixture 21, with the imaging device 30 on the first side of the first direction (see Figures 1 and 2). The support device 40 positions the imaging device 30 with respect to the reference plane 42 so that the imaging direction coincides with the second side from the first side of the first direction (see Figure 2). When the imaging device 30 is imaging the inspection surface 61, the vibration generator 28 sets the vibration frequency to a range of 10 to 300 Hz and the acceleration to a range of 0.1 to 2.0 G, causing the fixture 21 to vibrate in the first direction (see Figures 1 and 2). When the imaging device 30 is imaging the inspection surface 61, the illumination device 50 irradiates the inspection surface 61 with illumination light. The imaging device 30 images the inspection surface 61 when the imaging direction coincides with the first side to the second side of the first direction, the fixture 21 is vibrating in the first direction, and the inspection surface 61 is illuminated by illumination light.
[0047] <Modification Example> The embodiment can also be as follows. Some configurations of the modification examples shown below can also be adopted in appropriate combinations. Hereinafter, points different from the above will be described, and descriptions of the same points will be omitted as appropriate.
[0048] (1) The vibration generator 28 vibrates the mounting tool 21 in the first direction (see FIGS. 1 and 2). The vibration generator 28 may vibrate the mounting tool 21 in a direction different from the first direction. The direction different from the first direction intersects the first direction. Examples of the direction different from the first direction include a direction orthogonal to the first direction. Examples of the direction orthogonal to the first direction include the second direction, the third direction, and a direction intersecting both of these directions.
[0049] (2) The support device 40 uses the following first region of the fixing jig 41 as the reference plane 42 (see FIGS. 1 to 4). The first region has a perpendicular relationship with the imaging direction in the fixed state. The relationship between the reference plane and the imaging direction in the fixed state may be different from this. The relationship between the reference plane and the imaging direction in the fixed state is appropriately determined in consideration of various conditions. The reference plane may be the following second region of the fixing jig. The second region has a parallel relationship with the imaging direction in the fixed state. Assuming that the reference plane is set in the second region of the fixing jig. In the support device, the vertically articulated robot is driven to adjust this reference plane to the following state. In this state, the reference plane is set vertically. In this case, the reference plane is set perpendicular to the horizontal mounting surface 29 of the vibration generator 28. Similar to the surface inspection device 10 of the above-described embodiment (see FIGS. 1 and 2), the support device arranges the imaging device 30 opposite to the mounting tool 21 in the first direction with the imaging device 30 on the first side in the first direction with respect to the mounting tool 21. Also in this case, as described above, the imaging device 30 faces the inspection surface 61 of the inspection object 60 provided on the mounting tool 21 on the vibration generator 28 directly in the first direction.
[0050] (3) The surface inspection device 10 includes an illumination device 50 (see Figures 1 to 4). In the surface inspection device 10, the illumination device 50 may be omitted. Assume that the environment in which the surface inspection device 10 is installed has sufficient brightness. In this case, the illumination device 50 may be omitted in the surface inspection device 10. Whether or not to install the illumination device 50 is determined appropriately according to the state of the image captured by the imaging device 30.
[0051] (4) The surface inspection device 10 employs a vertical articulated robot as the support device 40 (see Figures 1 to 4). The support device may be different from the vertical articulated robot. The support device only needs to be able to position the imaging device 30 opposite the mounting fixture 21 in the first direction, with the imaging device 30 on the first side in the first direction relative to the mounting fixture 21. The support device does not need to include a mechanism for adjusting the position and orientation of the imaging device 30, or it may include a mechanism for adjusting one or both of the position and orientation of the imaging device 30.
[0052] The support device includes a linear motion mechanism and may perform all or part of the first relative movement, second relative movement, and third relative movement of the mounting fixture 21 and the imaging device 30. The first relative movement moves the imaging device 30 relative to the mounting fixture 21 in a first direction. The second relative movement moves the imaging device 30 relative to the mounting fixture 21 in a second direction. The third relative movement moves the imaging device 30 relative to the mounting fixture 21 in a third direction. In the support device, the first relative movement may be performed automatically or manually, the second relative movement may be performed automatically or manually, and the third relative movement may be performed automatically or manually.
[0053] The support device includes a rotation mechanism and may perform all or part of the first relative rotation, second relative rotation, and third relative rotation of the mounting fixture 21 and the imaging device 30. The first relative rotation rotates the imaging device 30 relative to the mounting fixture 21 around a rotation axis along a first direction. The second relative rotation rotates the imaging device 30 relative to the mounting fixture 21 around a rotation axis along a second direction. The third relative rotation rotates the imaging device 30 relative to the mounting fixture 21 around a rotation axis along a third direction. In the support device, the first relative rotation may be performed automatically or manually, the second relative rotation may be performed automatically or manually, and the third relative rotation may be performed automatically or manually.
[0054] The relative movement of the mounting fixture 21 and the imaging device 30 may involve moving only the mounting fixture 21, moving only the imaging device 30, or moving both the mounting fixture 21 and the imaging device 30 together. The relative rotation of the mounting fixture 21 and the imaging device 30 may involve rotating only the mounting fixture 21, rotating only the imaging device 30, or rotating both the mounting fixture 21 and the imaging device 30 together. The movement of the mounting fixture 21 may occur in conjunction with the movement of the mounting device 20. The rotation of the mounting fixture 21 may occur in conjunction with the rotation of the mounting device 20. In the above-described embodiment, the surface inspection device 10 uses a support device 40, which is a vertical articulated robot, to move and rotate the imaging device 30 (see Figures 1-4).
[0055] 10 Surface inspection device, 20 Installation device, 21 Installation fixture, 22 Housing, 23 Housing chamber, 24 Cover, 25 Positioning pin, 26 Positioning hole, 27 Imaging hole, 28 Vibration generator, 29 Mounting surface, 30 Imaging device, 31 Camera body, 32 Lens, 40 Support device, 41 Fixing jig, 42 Reference surface, 50 Illumination device, 60 Object to be inspected, 61 Inspection surface
Claims
1. A surface inspection device comprising: an installation device including an installation fixture on which an object to be inspected is placed; a photographing device for photographing the inspection surface of the object to be inspected, which is provided on the installation fixture; and a support device for supporting the photographing device, wherein the installation device includes a vibration generator for vibrating the installation fixture; the photographing device includes an event-based vision sensor; the support device is positioned such that the photographing device is on the first side of the first direction relative to the installation fixture, and the photographing device is positioned opposite the installation fixture in the first direction; and the vibration generator vibrates the installation fixture when the photographing device photographs the inspection surface.
2. The surface inspection apparatus according to claim 1, wherein the vibration generator vibrates the mounting fixture in the first direction.
3. A surface inspection apparatus according to claim 1 or 2, comprising an illumination device for irradiating illumination light onto the inspection surface of the object to be inspected, which is provided on the fixture, wherein the illumination device irradiates the inspection surface with illumination light when the imaging device photographs the inspection surface.