Appearance inspection device and appearance inspection method

Abstract

To assure the transportability of components and capture images of the components with high resolution.SOLUTION: A visual inspection device 1 comprises a conveyor 11, a camera 12, a plurality of mirrors 13a, 13b, 13c, 13d for reflecting an image of a workpiece W toward an imaging plane of the camera 12, mirror opening / closing mechanisms 14, 15, and a controller 90. The controller 90 is constituted so as to execute: first control for controlling the conveyor 11 so that the workpiece W is conveyed to an imaging region A2; second control for controlling the mirror opening / closing mechanisms 14, 15 so that the plurality of mirrors 13a, 13b, 13c, 13d move in the direction of the imaging region A2; third control for controlling the camera 12 so as to capture an image of the workpiece W; and fourth control for controlling the mirror opening / closing mechanisms 14, 15 so that the plurality of mirrors 13a, 13b, 13c, 13d move in a direction to separate from a conveyance path.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] One aspect of the present invention relates to an appearance inspection apparatus and an appearance inspection method for components.

Background Art

[0002] Patent Document 1 describes an appearance inspection apparatus that images the appearance of a component and inspects for the presence or absence of, for example, the shape of the electrodes of the component, surface defects, scratches, dirt, foreign substances, etc. The appearance inspection apparatus of Patent Document 1 includes imaging means with an imaging surface facing the bottom surface of the component, and mirrors provided corresponding to the four side surfaces of the component. The mirrors reflect the images of the four side surfaces of the component toward the imaging surface of the imaging means, and the imaging means images the images of the four side surfaces in addition to the bottom surface image.

[0003] According to such a configuration, since a plurality of surfaces of a component can be imaged by one imaging means, for example, compared with a configuration in which imaging means is provided for each surface of the component, the cost is reduced, and the imaging process is simplified by eliminating the need to switch the imaging means, etc.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the appearance inspection apparatus as described above, the component is transported to the imaging area and stopped in the imaging area for imaging processing. Here, from the viewpoint of performing imaging with high resolution, it is preferable that the above-described mirror is close to the component. On the other hand, from the viewpoint of appropriately transporting the component, it is necessary to separate the mirror from the component to such an extent that the component can be transported. Thus, conventionally, it has been difficult to achieve both the transportability of the component and the imaging of the component with high resolution.

[0006] One aspect of the present invention has been made in view of the above circumstances, and relates to an appearance inspection apparatus and an appearance inspection method that can ensure the transportability of parts and image the parts with high resolution in a configuration where a plurality of surfaces of a part are imaged by one imaging means.

Means for Solving the Problems

[0007] An appearance inspection apparatus according to one aspect of the present invention is an appearance inspection apparatus for inspecting the surface state of a part, including a transport unit configured to be able to transport a placed part to an imaging region along a transport path, an imaging unit facing the part transported to the imaging region in a first direction and imaging the part, a plurality of mirrors arranged so as to surround the part transported to the imaging region when viewed in the first direction and reflecting the image of the part toward the imaging surface of the imaging unit, a moving mechanism configured to be able to move the plurality of mirrors, and a control device. The control device executes a first control for controlling the transport unit so that the part is transported to the imaging region and stops in the imaging region, a second control for controlling the moving mechanism so that the plurality of mirrors move in the direction of the imaging region after the first control, a third control for controlling the imaging unit to image the part after the second control, and a fourth control for controlling the moving mechanism so that the plurality of mirrors move in a direction away from the transport path including the imaging region after the third control.

[0008] In the appearance inspection apparatus according to one aspect of the present invention, a plurality of mirrors that reflect the image of a component toward the imaging surface of the imaging unit are arranged so as to surround the component conveyed to the imaging region. Therefore, a plurality of surfaces of the component can be imaged by one imaging unit. For example, compared with a configuration in which imaging means is provided for each surface of the component, the cost is reduced, and the imaging process is simplified because switching of the imaging means and the like becomes unnecessary. And in the appearance inspection apparatus according to one aspect of the present invention, when the component has stopped in the imaging region, the moving mechanism is controlled so that the plurality of mirrors move in the direction of the imaging region, and then imaging of the component by the imaging unit is performed. In this way, since the plurality of mirrors are moved in the direction of the imaging region and imaging of the component is performed in that state, when imaging the component, the plurality of mirrors approach the component and the imaging frame is made small, so that imaging of the component with high resolution (high pixels) can be realized. Further, in the appearance inspection apparatus according to one aspect of the present invention, after imaging, since the plurality of mirrors are moved in a direction away from the conveyance path including the imaging region, the plurality of mirrors are not arranged in the conveyance path except during imaging (before and after imaging), and the plurality of mirrors do not interfere with the conveyance of the component. As described above, according to the appearance inspection apparatus according to one aspect of the present invention, by moving the plurality of mirrors by the control device, the conveyance property of the component can be ensured and the component can be imaged with high resolution.

[0009] The appearance inspection apparatus further includes a support unit that supports a component conveyed to the imaging region. At least the lower surface of the component is formed in an arch shape, and the surface of the support unit that supports the component may be formed in a V shape with a central portion recessed downward so as to correspond to the shape of the component formed in an arch shape. In this way, since the surface of the support unit that supports the component is formed in a V shape along the shape of the component, when the support unit receives the component, it is effectively suppressed that the component is placed on the support unit in a state of being displaced in the θ direction with respect to the axis of the support unit.

[0010] The above appearance inspection device further includes a pressing jig that presses a component conveyed to a positioning area upstream of the imaging area in the conveyance path from above and performs positioning in the front-rear direction. The control device is configured to further execute a fifth control for controlling the conveyance unit so that the component is conveyed to the positioning area and stops in the positioning area before the first control, and a sixth control for controlling the pressing jig so that the component is pressed before the first control after the fifth control. If the position (orientation) of the component conveyed to the imaging area is different from the assumption, it may not be possible to perform the inspection of the component after imaging with high accuracy. Regarding the position correction of the component, for example, it is conceivable to perform position correction using image software. However, even if such position correction is performed, it may not be possible to sufficiently ensure the inspection accuracy of the component. In this regard, in the positioning area upstream of the imaging area, the component is pressed by the pressing jig and the positioning of the component in the front-rear direction is performed (that is, the position correction of the component is actually performed instead of soft correction), so that the inspection accuracy based on the imaging result in the subsequent imaging area can be improved. Specifically, when the component is pressed from above by the pressing jig, the rolling deviation (the deviation in the direction in which an arched component rotates) of the component is corrected, and when the positioning of the component in the front-rear direction is performed by the pressing jig, the front-rear deviation of the component is corrected, and the inspection accuracy can be improved.

[0011] The component is substantially rectangular when viewed in the first direction, and the plurality of mirrors may include four mirrors arranged at the four corners of the component viewed in the first direction and reflecting the images of the corners. By arranging each mirror at the corner in this way, it is possible to image the two sides (the two sides viewed in the first direction) adjacent to the corner by each mirror, so that each surface of the component can be appropriately imaged.

[0012] The control device is configured to further execute a seventh control for determining the quality of a component based on the imaging result of the imaging unit in the third control. In the seventh control, after performing a correction process of correcting the dimensions by multiplying a reduction rate corresponding to the separation distance from the corner of the component, the quality of the component may be determined. By performing such a correction process, the actual dimensions can be estimated with high accuracy considering the separation distance from the corner, and the accuracy of determining the quality of the component can be improved.

[0013] The appearance inspection device may further include a first illumination that is disposed above the component conveyed to the imaging area and irradiates light to the component, and a second illumination that is disposed below the component conveyed to the imaging area and irradiates light to the component. By providing the second illumination that irradiates light from below the component in addition to the first illumination that irradiates light from above the component, the lower surface (bottom surface) of the component where light is difficult to be irradiated in the case of only the first illumination can also be appropriately irradiated with light, and an imaging result that is more likely to improve the inspection accuracy can be obtained.

[0014] An appearance inspection method according to an aspect of the present invention is an appearance inspection method for inspecting the surface state of a component, including: a first step of conveying the component to an imaging area by a conveying unit and stopping the component in the imaging area; a second step of moving, by a moving mechanism after the first step, a plurality of mirrors disposed so as to surround the component conveyed to the imaging area in the direction of the imaging area; a third step of imaging the component by an imaging unit after the second step; and a fourth step of moving, by the moving mechanism after the third step, the plurality of mirrors in a direction away from the imaging area.

Advantages of the Invention

[0015] According to an aspect of the present invention, in a configuration in which a plurality of surfaces of a component are imaged by one imaging means, it is possible to ensure the transportability of the component and image the component with high resolution.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2

Figure 3

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Figure 5

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Figure 7

Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0017] Hereinafter, embodiments will be described in detail with reference to the drawings. In the description, elements having the same element or the same function are denoted by the same reference numerals, and redundant descriptions are omitted.

[0018] FIG. 1 is a schematic diagram showing the overall configuration of the appearance inspection apparatus 1. The appearance inspection apparatus 1 shown in FIG. 1 is an apparatus for inspecting the surface state of a workpiece as a component. The appearance inspection apparatus 1 determines the quality of the workpiece by inspecting the surface state of the workpiece. Inspecting the surface state of the workpiece means inspecting whether there is a defect corresponding to a predetermined defect item on the surface of the workpiece. The predetermined defect items are, for example, chipping, cracking, dirt (stain), pitting, blackening, polishing defect, looseness, cutting defect, etc. Chipping is a defect in which a part of the workpiece W chips off and a concave portion is formed. Cracking is a defect in which a streak-like concave portion is formed. Dirt (stain) is, for example, a defect of remaining dirt due to insufficient cleaning. Pitting is a defect in which a round concave portion is formed. Blackening is a defect of deformation / contraction rate in the remaining polished portion (the portion that has not been polished sufficiently). A polishing defect is a defect in the portion that has been over-machined partially. Looseness is a defect caused by the height variation of the leg portion. A cutting defect is a defect in which the chamfering balance deteriorates. The specific inspection method will be described later. As shown in FIG. 1, the appearance inspection apparatus 1 includes an inspection unit 10 and a controller 90 (control device).

[0019] As shown in FIG. 1, the inspection unit 10 includes a conveyor 11 (transport unit), a camera 12 (imaging unit), a plurality of mirrors 13, mirror opening / closing mechanisms 14, 15, a support unit 16, a first illumination 17, second illuminations 18, 19, and a positioning jig 20 (see FIGS. 3(b) and 3(d)). Each component included in the inspection unit 10 is controlled by the controller 90. The appearance inspection apparatus 1 inspects the surface state of the workpiece W as a component according to the control of the controller 90. The workpiece W is, for example, a magnetic component.

[0020] FIG. 2 is a perspective view schematically showing a work W to be inspected. As shown in FIG. 2, the work W is formed in an arch shape. As shown in FIG. 2, the work W includes an outer R surface Wo formed in an arch shape, an inner R surface Wi formed in an arch shape on the back surface of the outer R surface Wo, A end surfaces Wa which are both end surfaces in the length direction of the work W, B end surfaces Wb which are both end surfaces in the width direction of the work W, a honeycomb surface Wy and a leg portion Wx connecting the lower end of the A end surface Wa and the end of the inner R surface Wi. The outer R surface Wo is a surface supported by a support portion 16 described later, and is formed in an arch shape along the X direction (see FIG. 3(b) etc.). Note that the work W is substantially rectangular when viewed in the vertical direction (first direction) as shown in FIG. 1.

[0021] Returning to FIG. 1, the conveyor 11 is a conveyor that conveys the work W put into the inspection unit 10 by an operator. That is, the conveyor 11 is a conveying unit configured to be able to convey the placed work W to the imaging area A2 along the conveying path. The conveyor 11 may be, for example, a timing belt conveyor having a timing belt 11a and a timing pulley 11b (see FIG. 3(b)). In this case, the power source of the conveyor 11 may be, for example, a servo motor (not shown). The conveyor 11 operates as follows by receiving a control signal from the controller 90. That is, the conveyor 11 conveys the work W put in by the operator and located in the input area A0 to the positioning area A1 and temporarily stops. In the positioning area A1, the positioning process of the work W is performed (details will be described later). Subsequently, the conveyor 11 conveys the work W located in the positioning area A1 to the imaging area A2 and temporarily stops. In the imaging area A2, the imaging process of the work W is performed (details will be described later). Subsequently, the conveyor 11 conveys the work W located in the imaging area A2 to the discharge area A3. The work W is discharged from the discharge area A3 to the outside of the inspection unit 10 and supplied to the subsequent process.

[0022] The support unit 16 is configured to support the workpiece W conveyed to the imaging area A2. The support unit 16 receives the workpiece W input by the operator in the input area A0 and supports the workpiece W conveyed by the conveyor 11. Note that in FIGS. 1, 3(a), and 3(b), the support unit 16 in the input area A0 before supporting the workpiece W is shown. With the workpiece W supported by the support unit 16, the support unit 16 is conveyed to the conveyor 11, whereby the workpiece W sequentially moves to the positioning area A1, the imaging area A2, and the discharge area A3.

[0023] Note that hereinafter, there may be cases where the vertical direction is described as the Z direction (first direction), the conveyance direction of the workpiece W by the conveyor 11 is described as the X direction, and the direction intersecting the Z direction and the X direction is described as the Y direction. FIGS. 1, 3(a), and 3(c) show views of the configuration of the inspection unit 10 as seen from above (viewed from the Z direction). FIGS. 3(b) and 3(e) show views of the configuration of the inspection unit 10 as seen from the Y direction. FIG. 3(d) shows a view of the configuration of the inspection unit 10 as seen from the X direction.

[0024] As shown in FIG. 3(b), the support surface 16a, which is the surface of the support unit 16 that supports the workpiece W, is formed in a V shape with the central portion recessed downward so as to correspond to the shape of the workpiece W formed in an arch shape (specifically, the shape of the outer R surface Wo). That is, the support surface 16a is recessed downward more at the central portion in the X direction. The support surface 16a may have substantially the entire surface thereof in contact with the outer R surface Wo of the workpiece W, or as shown in FIG. 3(b), it may not be in contact with the outer R surface Wo on the surface at both end portions in the X direction and may be in contact on the surface at the central portion in the X direction.

[0025] As shown in FIGS. 3(b) and 3(d), the positioning jig 20 is a pressing jig that presses the workpiece W conveyed to the positioning area A1 upstream of the imaging area A2 in the conveying path from above and positions the workpiece W in the Y direction, which is the front-rear direction of the workpiece W. As shown in FIG. 3(d), the positioning jig 20 has a flat plate-shaped main body 20a and protruding portions 20b and 20c provided at both ends in the Y direction of the main body 20a and extending downward. In response to the control of the controller 90, the positioning jig 20 approaches the workpiece W conveyed to the positioning area A1 from above, presses the workpiece W downward with the main body 20a, and presses the workpiece W from both ends in the Y direction by the protruding portions 20b and 20c. As shown in FIGS. 3(d) and 3(e), when the workpiece W is pressed downward by the main body 20a of the positioning jig 20, the rolling deviation (deviation in the direction in which the arched workpiece W rotates) of the workpiece W is corrected, and when the workpiece W is pressed from both ends in the Y direction by the protruding portions 20b and 20c, the positional deviation of the workpiece W in the Y direction is corrected.

[0026] Returning to FIG. 1, the camera 12 is an imaging unit that faces the workpiece W conveyed to the imaging area A2 in the Z direction (first direction) and images the workpiece W. The camera 12 performs imaging by receiving a control signal from the controller 90. The camera 12 transmits the imaging result to the controller 90.

[0027] The plurality of mirrors 13 includes four mirrors 13a, 13b, 13c, and 13d. Each of the mirrors 13a, 13b, 13c, and 13d is an optical element such as a prism, for example. Each of the mirrors 13a, 13b, 13c, and 13d is arranged so as to surround the workpiece W conveyed to the imaging region A2 when viewed in the Z direction (the first direction), and reflects the image of the workpiece W toward the imaging surface of the camera 12. Each of the mirrors 13a, 13b, 13c, and 13d is arranged at each of the four corners of the workpiece W which is substantially rectangular when viewed in the Z direction, and reflects the image of the corner. As shown in FIG. 1, when viewed in the Z direction, each of the mirrors 13a, 13b, 13c, and 13d is arranged at a position that is 45° with respect to the X direction and the Y direction. By providing each of the mirrors 13a, 13b, 13c, and 13d in this way, with respect to the two sides (the two sides viewed in the Z direction) close to the corners of the workpiece W, the image of the workpiece W is reflected toward the imaging surface of the camera 12.

[0028] The mirror opening / closing mechanism 14 is a moving mechanism configured such that the plurality of mirrors 13a and 13b can be opened and closed and moved. The mirror opening / closing mechanism 15 is a moving mechanism configured such that the plurality of mirrors 13c and 13d can be opened and closed and moved. The mirror opening / closing mechanisms 14 and 15 perform an opening / closing operation by receiving a control signal from the controller 90.

[0029] FIGS. 4(a) and 4(b) are diagrams for explaining the operations of the mirror opening / closing mechanisms 14 and 15. As shown in FIGS. 4(a) and 4(b), the mirror opening / closing mechanism 14 has a drive unit 14a that has a power source such as an actuator and is movable along the Y direction, and a connecting unit 14b that is connected to the drive unit 14a and is also connected to the mirrors 13a and 13b. The mirror opening / closing mechanism 15 has a drive unit 15a that has a power source such as an actuator and is movable along the Y direction, and a connecting unit 15b that is connected to the drive unit 15a and is also connected to the mirrors 13c and 13d.

[0030] FIG. 4(a) shows a state in which the driving units 14a and 15a have moved in a direction away from the conveyance path in response to the control from the controller 90. In such a state, since the plurality of mirrors 13a, 13b, 13c, and 13d are arranged away from the conveyance path of the workpiece W, the plurality of mirrors 13a, 13b, 13c, and 13d do not interfere with the conveyance of the workpiece W.

[0031] FIG. 4(b) shows a state in which the driving units 14a and 15a have moved in the direction of the conveyance path (specifically, in the direction of the imaging region A2) in response to the control from the controller 90. In such a state, since the plurality of mirrors 13a, 13b, 13c, and 13d are arranged close to the workpiece W, it is possible to reduce the frame size during imaging and realize imaging of the workpiece W with high resolution (high pixels).

[0032] Returning to FIG. 1, the first illumination 17 is an illumination that is arranged above the workpiece W conveyed to the imaging region A2 and irradiates light onto the workpiece W. The second illuminations 18 and 19 are illuminations that are arranged below the workpiece W conveyed to the imaging region A2 and irradiate light onto the workpiece W.

[0033] FIG. 5 is a diagram for explaining the first illumination 17 and the second illuminations 18 and 19. As shown in FIG. 5, the first illumination 17 is arranged below the camera 12 and above the workpiece W, and is formed in a ring shape so as not to block the space between the camera 12 and the workpiece W. The second illumination 18 is arranged below the workpiece W (see FIG. 5) so as to illuminate the surface of the workpiece W on the side where the image is reflected by the plurality of mirrors 13a and 13b from below (see FIG. 1). The second illumination 19 is arranged below the workpiece W (see FIG. 5) so as to illuminate the surface of the workpiece W on the side where the image is reflected by the plurality of mirrors 13c and 13d from below (see FIG. 1). For the second illuminations 18 and 19, for example, variable illuminations are used, and by illuminating the entire bottom surface of the workpiece W through a diffuser plate, imaging without partial halation unevenness is possible.

[0034] FIG. 6 is a diagram showing an example of an imaging result by the camera 12. As shown in FIG. 6, the mirrors 13a, 13b, 13c, 13d are arranged at positions that are 45° with respect to the X direction and the Y direction so as to surround the work W, and imaging is performed in a state where light is irradiated from the second illuminations 18 and 19 from below the work W. Thus, with one camera 12, not only the inner R surface Wi of the work W but also two sides or the like adjacent to the corners of the work W can be appropriately imaged.

[0035] Returning to FIG. 1, the controller 90 is configured to be capable of executing control (control process) of each component included in the appearance inspection apparatus 1 to inspect a predetermined inspection surface of the work W and determination (determination process) of the surface state of the work W based on the inspection result. Hereinafter, the control process and the determination process will be described in detail.

[0036] In the control process, first, the controller 90 controls the conveyor 11 so that the work W supported by the support portion 16 is conveyed along the conveyance path to the positioning region A1 and stops in the positioning region A1 (executes fifth control).

[0037] After the above-described fifth control, the controller 90 controls the positioning jig 20 so that the work W is positioned in the Y direction in the positioning region A1 as shown in FIGS. 3(b) and 3(d) etc. (executes sixth control).

[0038] After the above-described sixth control, the controller 90 controls the conveyor 11 so that the work W is conveyed to the imaging region A2 and stops in the imaging region A2 as shown in FIGS. 3(a) and 3(b) etc. (executes first control).

[0039] After the above-described first control, as shown in FIG. 4(b), the controller 90 controls the mirror opening / closing mechanisms 14 and 15 so that the plurality of mirrors 13a, 13b, 13c, 13d move in the direction of the imaging region A2 (executes second control).

[0040] After the second control described above, the controller 90 controls the camera 12 to image the work W (executes the third control).

[0041] After the third control described above, the controller 90 controls the mirror opening / closing mechanisms 14 and 15 so that the plurality of mirrors 13a, 13b, 13c, and 13d move away from the conveyance path including the imaging area A2 (executes the fourth control).

[0042] In the determination process, the controller 90 determines the quality of the work W based on the imaging result of the camera 12 in the third control described above (executes the seventh control). The controller 90 determines, for example, whether information such as dimensions, area, and color shading indicated by the imaging result of the camera 12 is within a predetermined normal range. The controller 90 may determine whether information such as dimensions, area, and color shading is normal (the same as the master image) by comparing the imaging result of the camera 12 with a master image that is an image of a non-defective work W. Among each defective item, for example, for chips, cracks, scratches, and burrs, determination can be made according to the dimensions indicated by the imaging result of the camera 12. Also, for example, for stains, determination can be made according to the shading and area indicated by the imaging result of the camera 12. Also, for example, for black edges, polishing defects, and cutting defects, determination can be made using the imaging result of the camera 12. Specifically, for black edges, determination can be made from the area indicated by the imaging result, for polishing defects, determination can be made from the width indicated by the imaging result, and for cutting defects, determination can be made from the dimensions indicated by the imaging result.

[0043] The controller 90 may perform various quality determinations in a predetermined order, and when a defect is determined in any of the quality determinations, determine that the work W is a defective product without performing subsequent quality determinations. The controller 90 may identify the defective item (for example, black edges, etc.) for the work W determined to be defective, and control so that the work W determined to be defective is discharged to the discharge position for each defective item.

[0044] Note that when determining a non-defective work W, the controller 90 may determine the non-defective work W after performing a split correction process of correcting the dimensions by multiplying by a reduction rate corresponding to the distance from the corner of the work W.

[0045] FIG. 7 is a diagram for explaining the split correction process. Regarding the periphery of the corner of the work W, the area is divided into five parts, and the actual dimensions are estimated with high precision by multiplying the reduction rate for each area. In the example shown in FIG. 7, the area around the corner of the work W is divided into five parts. Specifically, for the two sides extending from the corner, the area from 3 mm behind the center of the work W (behind when viewed from the corner) to the center is set as the inspection area, and it is divided into five areas including the area of 3 mm from the corner of the work W (3 mm on each of the two sides) and the areas obtained by dividing the remaining inspection area on each of the two sides into two parts. Note that for each of the areas divided as described above, the areas may overlap by about 3 mm, for example. For the areas divided into five parts in this way, the reduction rate corresponding to the distance from the corner is multiplied to estimate the dimensions. Specifically, in the example shown in FIG. 7, a reduction rate of 98% is multiplied for the area of 3 mm from the corner, a reduction rate of 94% is multiplied for the area closer to the corner among the areas divided into two parts, and a reduction rate of 82% is multiplied for the area closer to the center among the areas divided into two parts to estimate the dimensions respectively. Such reduction rates may be set based on the actual verification results. Note that when a defect is detected at a location where the areas overlap, the smaller reduction rate among the reduction rates of the areas divided into two parts may be multiplied.

[0046] The hardware of the controller 90 is constituted by, for example, one or more control computers. As a configuration on the hardware, the controller 90 has, for example, a circuit 900 shown in FIG. 8. The circuit 900 has a processor 901, a memory 902, a storage 903, an input / output port 904, and a driver 905. The driver 905 is a circuit for driving various actuators of the inspection unit 10. The input / output port 904 performs input / output of external signals and also performs input / output of signals to / from the driver 905. The processor 901 executes a program in cooperation with at least one of the memory 902 and the storage 903, and executes input / output of signals via the input / output port 904, thereby constituting the above-described functional modules.

[0047] Note that the configuration on the hardware of the controller 90 is not necessarily limited to one that constitutes functional modules by executing a program. For example, the controller 90 may constitute these functional modules by a dedicated logic circuit or an ASIC (Application Specific Integrated Circuit) integrating the same.

[0048] Next, the appearance inspection process (appearance inspection method) of the workpiece W by the appearance inspection apparatus 1 will be described with reference to FIG. 9.

[0049] As shown in FIG. 9, in the appearance inspection process, first, the workpiece W is conveyed on the conveyor 11 (step S1). The workpiece W is conveyed by the conveyor 11 while being supported by the support portion 16 on the conveyor 11 and reaches the positioning region A1 (step S2). Then, in the positioning region A1, the positioning jig 20 presses the workpiece W from above and performs positioning in the Y direction, which is the front-rear direction of the workpiece W (step S3).

[0050] Thereafter, the workpiece W is conveyed by the conveyor 11, conveyed to the imaging area A2, and stopped (step S4, the first step). Then, by the mirror opening / closing mechanisms 14 and 15, a mirror closing movement is performed in which the plurality of mirrors 13a, 13b, 13c, and 13d move in the direction of the conveyance path (specifically, the direction of the imaging area A2) (step S5, the second step).

[0051] Then, a camera inspection is performed in which the workpiece W is imaged by the camera 12 (step S6, the third step). Thereafter, by the mirror opening / closing mechanisms 14 and 15, a mirror opening movement is performed in which the plurality of mirrors 13a, 13b, 13c, and 13d move in a direction away from the conveyance path (a direction away from the imaging area A2) (step S7, the fourth step).

[0052] Then, a pass / fail determination of the workpiece W is made based on the camera inspection (step S8). The workpiece W that is a defective product is discharged as a defective product (step S9), and the workpiece W that is a non-defective product is discharged as a non-defective product (step S10).

[0053] Next, the operation and effect of the appearance inspection apparatus 1 according to the present embodiment will be described.

[0054] The appearance inspection device 1 according to this embodiment is an appearance inspection device that inspects the surface state of a workpiece W, and includes a conveyor 11 configured to be able to convey the placed workpiece W along a conveyance path to an imaging region A2, a camera 12 that faces the workpiece W conveyed to the imaging region A2 in the Z direction and images the workpiece W, a plurality of mirrors 13a, 13b, 13c, 13d that are arranged so as to surround the workpiece W conveyed to the imaging region A2 when viewed in the Z direction and reflect the image of the workpiece W toward the imaging surface of the camera 12, mirror opening / closing mechanisms 14, 15 configured to be able to move the plurality of mirrors 13a, 13b, 13c, 13d, and a controller 90. The controller 90 is configured to execute a first control for controlling the conveyor 11 so that the workpiece W is conveyed to the imaging region A2 and stops in the imaging region A2, a second control for controlling the mirror opening / closing mechanisms 14, 15 so that the plurality of mirrors 13a, 13b, 13c, 13d move in the direction of the imaging region A2 after the first control, a third control for controlling the camera 12 to image the workpiece W after the second control, and a fourth control for controlling the mirror opening / closing mechanisms 14, 15 so that the plurality of mirrors 13a, 13b, 13c, 13d move in a direction away from the conveyance path including the imaging region A2 after the third control.

[0055] In the appearance inspection apparatus 1 according to the present embodiment, since a plurality of mirrors 13a, 13b, 13c, 13d that reflect the image of the work W toward the imaging surface of the camera 12 are arranged so as to surround the work W conveyed to the imaging region, a plurality of surfaces of the work W can be imaged by one camera 12. For example, compared with a configuration in which imaging means is provided for each surface of the work W, the cost is reduced, and the imaging process is simplified because switching of the imaging means and the like becomes unnecessary. And in the appearance inspection apparatus 1 according to the present embodiment, when the work W stops in the imaging region A2, the mirror opening / closing mechanisms 14 and 15 are controlled so that the plurality of mirrors 13a, 13b, 13c, 13d move in the direction of the imaging region A2, and then the work W is imaged by the camera 12. In this way, since the plurality of mirrors 13a, 13b, 13c, 13d are moved in the direction of the imaging region A2 and the work W is imaged in that state, the work W is imaged with the plurality of mirrors 13a, 13b, 13c, 13d approaching the work W and the imaging frame being reduced, so that imaging of the work W with high resolution (high pixels) can be realized. Further, in the appearance inspection apparatus 1 according to the present embodiment, after imaging, since the plurality of mirrors 13a, 13b, 13c, 13d are moved in a direction away from the conveyance path including the imaging region A2, the plurality of mirrors 13a, 13b, 13c, 13d are not arranged in the conveyance path except during imaging (before and after imaging), and the plurality of mirrors 13a, 13b, 13c, 13d do not interfere with the conveyance of the work W. As described above, according to the appearance inspection apparatus 1 according to the present embodiment, the controller 90 moves the mirror opening / closing mechanisms 14 and 15 to move the plurality of mirrors 13a, 13b, 13c, 13d, thereby ensuring the conveyance property of the work W and imaging the work W with high resolution.

[0056] The above-described appearance inspection device 1 further includes a support portion 16 that supports the workpiece W conveyed to the imaging region A2. The workpiece W has at least its lower surface formed in an arch shape, and the surface of the support portion 16 that supports the workpiece W may be formed in a V shape with a central portion recessed downward so as to correspond to the shape of the workpiece W formed in an arch shape. In this way, since the surface of the support portion 16 that supports the workpiece W is formed in a V shape along the shape of the component, when the support portion 16 receives the workpiece W, it is effectively suppressed that the workpiece W is placed on the support portion 16 in a state of being displaced in the θ direction with respect to the axis of the support portion 16.

[0057] The above-described appearance inspection apparatus 1 further includes a positioning jig 20 that presses the workpiece W conveyed to the positioning region A1 upstream of the imaging region A2 in the conveyance path from above and performs positioning in the front-rear direction. The controller 90 controls the conveyor 11 so that the workpiece W is conveyed to the positioning region A1 and stops in the positioning region A1 in the fifth control before the first control, and controls the positioning jig 20 so that the workpiece W is pressed in the sixth control after the fifth control and before the first control. It may be configured to further execute. When the position (orientation) of the workpiece W conveyed to the imaging region A2 is different from the assumption, it may not be possible to perform the inspection of the workpiece W after imaging with high accuracy. Regarding the position correction of the workpiece W, for example, position correction by image software may be considered. However, even if such position correction is performed, the inspection accuracy of the workpiece W may not be sufficiently ensured. In this regard, in the positioning region A1 upstream of the imaging region A2, the workpiece W is pressed by the positioning jig 20 and the positioning of the workpiece W in the front-rear direction is performed (that is, the position correction of the workpiece W is actually performed instead of soft correction), thereby improving the inspection accuracy based on the imaging result in the subsequent imaging region A2. Specifically, when the workpiece W is pressed from above by the positioning jig 20, the rolling deviation (deviation in the direction in which the arch-shaped workpiece W rotates) of the workpiece W is corrected, and when the positioning jig 20 positions the workpiece W in the front-rear direction, the front-rear deviation of the workpiece W is corrected, and the inspection accuracy can be improved.

[0058] The workpiece W is substantially rectangular when viewed in the Z direction, and the plurality of mirrors 13a, 13b, 13c, 13d may include four mirrors 13a, 13b, 13c, 13d arranged at the four corners of the workpiece W when viewed in the Z direction and reflecting the images of the corners. By arranging each of the mirrors 13a, 13b, 13c, 13d at the corners in this way, it is possible to image the two sides (the two sides when viewed in the Z direction) close to the corners by each of the mirrors 13a, 13b, 13c, 13d, so that each surface of the workpiece W can be appropriately imaged.

[0059] The controller 90 is configured to further execute a seventh control for determining the quality of the workpiece W based on the imaging result of the camera 12 in the third control. In the seventh control, after performing a correction process of correcting the dimensions by multiplying by a reduction rate corresponding to the separation distance from the corner of the workpiece W, the quality of the workpiece W may be determined. By implementing such a correction process, the actual dimensions can be estimated with high accuracy considering the separation distance from the corner, and the accuracy of determining the quality of the workpiece W can be improved.

[0060] The appearance inspection device 1 may further include a first illumination 17 that is disposed above the workpiece W conveyed to the imaging region A2 and irradiates light onto the workpiece W, and second illuminations 18 and 19 that are disposed below the workpiece W conveyed to the imaging region A2 and irradiate light onto the workpiece W. In addition to the first illumination 17 that irradiates light from above the workpiece W, by providing the second illuminations 18 and 19 that irradiate light from below the workpiece W, the lower surface (bottom surface) of the workpiece W where it is difficult to irradiate light in the case of only the first illumination 17 can also be appropriately irradiated with light, and it is possible to obtain an imaging result that is more likely to improve the inspection accuracy.

Description of Reference Numerals

[0061] 1... Appearance inspection device, 11... Conveyor (transport unit), 12... Camera (imaging unit), 13a, 13b, 13c, 13d... Mirrors, 14, 15... Mirror opening / closing mechanism (moving mechanism), 16... Support part, 17... First illumination, 18, 19... Second illuminations, 20... Positioning jig (holding jig), 90... Controller (control device), A1... Positioning region, A2... Imaging region, W... Workpiece (part).

Claims

1. An appearance inspection apparatus for inspecting the surface state of a component, comprising: a transport unit configured to be able to transport the placed component along a transport path to an imaging region; an imaging unit that faces the component transported to the imaging region in a first direction and images the component; a plurality of mirrors arranged so as to surround the component transported to the imaging region when viewed in the first direction, and reflecting the image of the component toward the imaging surface of the imaging unit; a moving mechanism configured to be able to move the plurality of mirrors; a control device, and the control device is configured to:[[]]END]] execute a first control for controlling the transport unit so that the component is transported to the imaging region and stops in the imaging region, a second control for controlling the moving mechanism so that the plurality of mirrors move in the direction of the imaging region after the first control, a third control for controlling the imaging unit to image the component after the second control, and a fourth control for controlling the moving mechanism so that the plurality of mirrors move in a direction away from the transport path including the imaging region after the third control; further comprising a support unit for supporting the component transported to the imaging region; at least the lower surface of the component is formed in an arch shape; the surface of the support unit that supports the component is formed in a V shape with a central portion recessed downward so as to correspond to the shape of the component formed in an arch shape; further comprising a pressing jig for pressing the component transported to a positioning region upstream of the imaging region in the transport path from above and performing positioning in the front-rear direction; the control device is further configured to execute a fifth control for controlling the transport unit so that the component is transported to the positioning region and stops in the positioning region before the first control, and a sixth control for controlling the pressing jig so that the component is pressed after the fifth control and before the first control. An appearance inspection apparatus.

2. An appearance inspection apparatus for inspecting the surface state of a component, comprising: a transport unit configured to be able to transport the placed component along a transport path to an imaging region; an imaging unit that faces the component transported to the imaging region in a first direction and images the component; a plurality of mirrors arranged so as to surround the component transported to the imaging region when viewed in the first direction, and reflecting the image of the component toward the imaging surface of the imaging unit; A moving mechanism configured to movably arrange the plurality of mirrors; A control device, and; The control device: Performs first control to control the transport unit so that the component is transported to the imaging region and stops in the imaging region, second control to control the moving mechanism so that the plurality of mirrors move in the direction of the imaging region after the first control, third control to control the imaging unit to image the component after the second control, and fourth control to control the moving mechanism so that the plurality of mirrors move in a direction away from the transport path including the imaging region after the third control. The component is substantially rectangular when viewed in the first direction. The plurality of mirrors includes four mirrors arranged at four corner portions of the component when viewed in the first direction and reflecting images of the corner portions. The control device is further configured to perform seventh control to determine the quality of the component based on the imaging result of the imaging unit in the third control. In the seventh control, after performing correction processing to correct the dimensions by multiplying by a reduction rate corresponding to the distance from the corner portion in the component, a non-defective component of the component is determined. An appearance inspection device.

3. A first illumination disposed above the component transported to the imaging region and irradiating the component with light; The appearance inspection device according to claim 1 or 2, further comprising a second illumination disposed below the component transported to the imaging region and irradiating the component with light.

4. An appearance inspection method for inspecting the surface state of a component, comprising: A first step of transporting a component to an imaging region along a transport path by a transport unit and stopping the component in the imaging region; A second step of moving, by a moving mechanism, a plurality of mirrors arranged to surround the component transported to the imaging region in the direction of the imaging region after the first step; A third step of imaging the component by an imaging unit after the second step; A fourth step of moving, by the moving mechanism, the plurality of mirrors in a direction away from the imaging region after the third step, and At least the lower surface of the component is formed in an arch shape, The surface of the support portion that supports the component in the support portion that supports the component transported to the imaging region is formed in a V shape with a central portion recessed downward so as to correspond to the shape of the component formed in an arch shape. Before the first step, a fifth step of conveying the component by the conveying unit to a positioning region upstream of the imaging region in the conveying path and stopping the component at the positioning region; After the fifth step and before the first step, a sixth step of pressing the component held at the positioning region from above and performing positioning in the front-rear direction by a pressing jig for pressing the component; An appearance inspection method further including.

5. An appearance inspection method for inspecting the surface state of a component, A first step of conveying a component to an imaging region along a conveying path by a conveying unit and stopping the component at the imaging region; After the first step, a second step of moving a plurality of mirrors arranged to surround the component conveyed to the imaging region in the direction of the imaging region by a moving mechanism; After the second step, a third step of imaging the component by an imaging unit; After the third step, a fourth step of moving the plurality of mirrors away from the imaging region by the moving mechanism; including, The component is substantially rectangular when viewed in a first direction in which the component and the imaging unit face each other, The plurality of mirrors includes four mirrors arranged at four corners of the component viewed in the first direction and reflecting images of the corners, Further including a seventh step of determining the quality of the component based on the imaging result of the imaging unit in the third step, In the seventh step, after performing a correction process of correcting the dimensions by multiplying by a reduction rate corresponding to the distance from the corner of the component, determining a non-defective product of the component; An appearance inspection method.

Images