CN115876117A - Appearance inspection device and appearance inspection method - Google Patents

Abstract

The invention provides an appearance inspection device and an appearance inspection method. The appearance inspection device comprises a conveyor, a camera, a plurality of reflectors for reflecting the image of the workpiece towards the camera surface of the camera, a reflector opening and closing mechanism and a controller, wherein the controller can execute the following control: a first control of controlling the conveyor to convey the workpiece to the imaging area; a second control for controlling the mirror opening/closing mechanism to move the plurality of mirrors in the direction of the imaging area; a third control of controlling the camera to photograph the workpiece; and a fourth control for controlling the mirror opening/closing mechanism so that the plurality of mirrors move in a direction away from the transport path.

Description

Appearance inspection device and appearance inspection method

Technical Field

One aspect of the present invention relates to an appearance inspection apparatus and an appearance inspection method for a component.

Background

Jp 2009-276338 a describes an appearance inspection device that images the appearance of a component and inspects the presence or absence of defects, scratches, dirt, foreign matter, and the like on the electrode shape and surface of the component. The appearance inspection device disclosed in japanese patent application laid-open No. 2009-276338 includes: an image pickup unit for directing an image pickup surface to a position facing a bottom surface of the member; and a mirror provided corresponding to the 4 side surfaces of the member, the mirror reflecting images of the four side surfaces of the member toward an imaging surface of the imaging unit, the imaging unit capturing images of the four side surfaces in addition to the bottom surface image.

According to this configuration, since a plurality of surfaces of the component can be imaged by one imaging unit, for example, the cost can be reduced as compared with a configuration in which an imaging unit is provided for each surface of the component, and switching of the imaging unit or the like is not necessary, whereby the imaging process can be simplified.

Disclosure of Invention

In the appearance inspection apparatus of the above type, the component is conveyed to the imaging area, and the imaging process is performed by stopping the component in the imaging area. Here, the mirror proximity member is preferable from the viewpoint of performing imaging at high resolution. On the other hand, from the viewpoint of appropriately conveying the member, it is necessary to make the mirror apart from the member to such an extent that the member can be conveyed. As described above, it is difficult to achieve both of the transportation of the component and the component imaging at high resolution.

An aspect of the present invention has been made in view of the above circumstances, and an object thereof is to provide an appearance inspection apparatus and an appearance inspection method that can image a component at high resolution while ensuring the transportation of the component in a configuration in which a plurality of surfaces of the component are imaged by one imaging unit.

An aspect of the present invention provides an appearance inspection apparatus for inspecting a surface state of a component, the appearance inspection apparatus including: a conveying unit configured to convey the mounted component to an imaging area along a conveying path; an imaging unit that faces the member conveyed to the imaging region in the first direction and that images the member; a plurality of mirrors which are arranged so as to surround the member conveyed to the imaging region when viewed from the first direction, and which reflect an image of the member toward an imaging surface of the imaging unit; a moving mechanism configured to be able to move the plurality of mirrors; and a control device configured to be capable of executing the following control: a first control unit that controls the transport unit to transport the component to the imaging area and stop the component in the imaging area; a second control of controlling the moving mechanism to move the plurality of mirrors in the direction of the imaging area after the first control; a third control of controlling the image pickup section to pick up the component after the second control; and a fourth control of controlling the moving mechanism to move the plurality of mirrors in a direction away from the transport path including the imaging region after the third control.

In the visual inspection apparatus according to one aspect of the present invention, since the plurality of mirrors that reflect the image of the component toward the imaging surface of the imaging unit are disposed so as to surround the component transported to the imaging area, the plurality of surfaces of the component can be imaged by one imaging unit, and thus, for example, compared to a configuration in which an imaging unit is provided for each surface of the component, the cost is reduced, and switching of the imaging unit or the like is not necessary, whereby the imaging process can be simplified. In the visual inspection apparatus according to one aspect of the present invention, the moving mechanism is controlled to move the plurality of mirrors in the direction of the imaging area in a state where the component is stopped in the imaging area, and thereafter, component imaging by the imaging unit is performed. In this way, by moving the plurality of mirrors in the direction of the imaging area and performing imaging of the component in this state, it is possible to perform imaging of the component in a state where the plurality of mirrors are close to the component and the imaging frame is reduced at the time of imaging of the component, and therefore, imaging of the component at high resolution (high pixels) can be realized. Further, in the appearance inspection device according to one aspect of the present invention, since the plurality of mirrors are moved in a direction away from the conveyance path including the imaging region after imaging, 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 conveyance of the component. As described above, according to the visual inspection apparatus of one aspect of the present invention, the controller causes the moving mechanism to move the plurality of mirrors, thereby enabling the component to be picked up at a high resolution while ensuring the transportation performance of the component.

The visual inspection device may further include a support portion that supports the member conveyed to the imaging region, at least a lower surface of the member being formed in an arcuate shape, and a surface of the support member of the support portion may be formed in a V-shape with a central portion thereof depressed downward so as to correspond to the shape of the member formed in the arcuate shape. In this way, by forming the surface of the support member of the support portion in a V-shape along the shape of the member, when the support portion receives the member, the member can be efficiently prevented from being mounted on the support portion in a state of being displaced in the θ direction with respect to the axis of the support portion.

The appearance inspection apparatus may further include a pressing jig that presses a member conveyed to a positioning region on an upstream side of the imaging region in the conveyance path from above and performs positioning in a front-rear direction, and the control device may be configured to perform: a fifth control of controlling the conveying section to convey the component to the positioning area and stop the component in the positioning area, prior to the first control; and a sixth control that controls the pressing jig so that the component is pressed after the fifth control and before the first control. When the position (orientation) of the component conveyed to the imaging region is different from the assumed position, the component after imaging may not be inspected with high accuracy. For the position correction of the component, for example, it is conceivable to perform the position correction by image software, but even if such position correction is performed, the inspection accuracy of the component may not be sufficiently ensured. In this regard, by pressing the component with the pressing jig in the positioning region on the upstream side of the imaging region and positioning the component in the front-rear direction (that is, by actually correcting the position of the component instead of correcting the software), the inspection accuracy of the subsequent imaging region based on the imaging result can be improved. Specifically, by pressing the member from above with the pressing jig, the rolling displacement of the member (displacement in the direction in which the arch member rotates) can be corrected, and by positioning the member in the front-rear direction with the pressing jig, the front-rear displacement of the member can be corrected, and the inspection accuracy can be improved.

The member may have a substantially rectangular shape when viewed from the first direction, and the plurality of mirrors may include four mirrors that are disposed at four corners of the member when viewed from the first direction, respectively, and reflect images of the corners. As described above, since the mirrors are arranged at the corner portions, two sides (two sides viewed in the first direction) close to the corner portions can be imaged by the mirrors, and thus, the respective surfaces of the member can be appropriately imaged.

The control device may be configured to be able to execute a seventh control of determining whether or not the component is a good component based on an imaging result of the imaging unit in the third control, and the control device may be configured to determine whether or not the component is a good component after performing a correction process of correcting the size by multiplying a reduction rate corresponding to a distance from the corner in the component. By performing such correction processing, the actual dimension can be estimated with high accuracy in consideration of the distance from the corner, and the accuracy of determining whether or not the component is good can be improved.

The appearance inspection apparatus may further include: a first illumination unit which is disposed above the component transported to the imaging region and irradiates the component with light; and a second illumination unit which is disposed below the component transported to the imaging region and irradiates the component with light. By providing the second illumination for irradiating light from below the component in addition to the first illumination for irradiating light from above the component, light can be appropriately irradiated to the lower surface (bottom surface) of the component which is difficult to irradiate light when only the first illumination is provided, and an imaging result which can more easily improve inspection accuracy can be obtained.

An aspect of the present invention provides an appearance inspection method for inspecting a 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, the plurality of mirrors arranged so as to surround the member transported to the imaging region in a direction toward the imaging region after the first step; a third step of, after the second step, imaging the component by the imaging section; and a fourth step of moving the plurality of mirrors in a direction away from the imaging region by the moving mechanism after the third step.

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 unit, the component can be imaged at high resolution while ensuring transportability of the component.

Drawings

Fig. 1 is a schematic diagram showing the overall configuration of the appearance inspection apparatus.

Fig. 2 is a perspective view schematically showing a workpiece as an inspection target.

Fig. 3 is a diagram illustrating the state of each region.

Fig. 4 is a diagram illustrating an operation of the mirror opening/closing mechanism.

Fig. 5 is a diagram illustrating the first illumination and the second illumination.

Fig. 6 is a diagram showing an example of the imaging result.

Fig. 7 is a diagram illustrating division correction.

Fig. 8 is a hardware configuration diagram of the controller.

Fig. 9 is a flowchart showing the appearance inspection process.

Detailed Description

The embodiments will be described in detail below with reference to the drawings. In the description, the same elements or elements having the same function are denoted by the same reference numerals, and redundant description thereof is omitted.

Fig. 1 is a schematic diagram showing the overall configuration of an appearance inspection apparatus 1. The appearance inspection apparatus 1 shown in fig. 1 is an apparatus for inspecting the surface condition of a workpiece as a component. The appearance inspection apparatus 1 inspects the surface state of the workpiece to determine whether the workpiece is good. The inspection of the surface state of the workpiece means to inspect whether or not a defect corresponding to a predetermined defective item has occurred on the surface of the workpiece. The predetermined defect items include scratches, cracks, stains (spots), pitting, orange peel, polishing defects, loosening, cutting defects, and the like. The scratch is a defect in which a part of the workpiece W is scratched to generate a dent portion. The cracks are defects that cause streaky dents. The stain (spot) is a defect of stain remaining due to insufficient cleaning, for example. The pitting corrosion is a defect that a circular depressed portion is generated. Orange peel is a residue of polishing (a portion that cannot be polished sufficiently) and is deformed, resulting in poor shrinkage. The polishing failure is a partial failure resulting from partial overpolishing. The looseness is a defect caused by a height deviation of the leg portion. The cutting defect is a defect resulting from a deterioration in the chamfer balance. The specific inspection method will be described later. As shown in fig. 1, the appearance inspection apparatus 1 has an inspection unit 10 and a controller 90 (control device).

As shown in fig. 1, the inspection unit 10 includes a conveyor 11 (conveying unit), a camera 12 (imaging unit), a plurality of mirrors 13, mirror opening and closing mechanisms 14 and 15, a support unit 16, a first illumination 17, second illumination 18 and 19, and a positioning jig 20 (see fig. 3 (b) and 3 (d)). Each structure 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 under the control of the controller 90. The workpiece W is, for example, a magnetic member.

Fig. 2 is a perspective view schematically showing a workpiece W as an inspection target. As shown in fig. 2, the workpiece W is formed in an arch shape. As shown in fig. 2, the workpiece W has: an outer R face Wo formed in an arch shape; the back surface of the outer R surface Wo is an arched inner R surface Wi; end faces a and Wa at both ends of the workpiece W in the longitudinal direction; the end surfaces Wb, which are both end surfaces in the width direction of the workpiece W; and an airfoil Wy and a combined part 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 arcuate shape along the X direction (see fig. 3 (b) and the like). Further, as shown in fig. 1, the workpiece W has a substantially rectangular shape when viewed from the up-down direction (first direction).

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

The support portion 16 is configured to support the workpiece W conveyed to the imaging area A2. The support portion 16 receives the workpiece W input by the operator in the input area A0, and supports the workpiece W conveyed by the conveyor 11. Fig. 1, 3 (a) and 3 (b) show the support portion 16 in the input area A0 before supporting the workpiece W. In a state where the workpiece W is supported by the support portion 16, the support portion 16 is conveyed by the conveyor 11, whereby the workpiece W is sequentially moved to the positioning area A1, the imaging area A2, and the discharge area A3.

Hereinafter, the vertical direction is sometimes referred to as the Z direction (first direction), the conveying direction of the workpiece W by the conveyor 11 is sometimes referred to as the X direction, and the direction intersecting the Z direction and the X direction is sometimes referred to as the Y direction. Fig. 1, 3 (a) and 3 (c) show diagrams (views seen from the Z direction) in which the structure of the inspection unit 10 is viewed from above. Fig. 3 (b) and 3 (e) show views of the structure of the inspection unit 10 viewed from the Y direction. Fig. 3 (d) shows a view of the structure of the inspection unit 10 as viewed from the X direction.

As shown in fig. 3 (b), a support surface 16a, which is a surface of the support portion 16 that supports the workpiece W, is formed in a V-shape having a center 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 toward the center portion in the X direction. The support surface 16a may be in contact with the outer R surface Wo of the workpiece W over substantially the entire surface thereof, or may be in contact with the surfaces on both end portions in the X direction and not in contact with the outer R surface Wo of the surface in the central portion in the X direction, as shown in fig. 3 (b).

As shown in fig. 3 (b) and 3 (d), the positioning jig 20 is a pressing jig that presses the workpiece W conveyed to the positioning area A1 on the upstream side of the imaging area A2 in the conveying path from above and performs positioning of the workpiece W in the Y direction, which is the front-rear direction. As shown in fig. 3 (d), the positioning jig 20 includes: a flat plate-like body portion 20a; and protruding portions 20b, 20c provided at both ends of the main body portion 20a in the Y direction and extending downward. The positioning jig 20 approaches the workpiece W conveyed to the positioning area A1 from above under the control of the controller 90, and holds the workpiece W downward by the main body 20a and also holds the workpiece W from both end portions in the Y direction by the protruding portions 20b and 20c. As shown in fig. 3d and 3 e, the workpiece W is pressed downward by the main body 20a of the positioning jig 20, whereby rolling displacement of the workpiece W (displacement in the direction in which the arched workpiece W rotates) is corrected, and at the same time, the workpiece W is pressed from both end portions in the Y direction by the protruding portions 20b and 20c, whereby positional displacement in the Y direction of the workpiece W is corrected.

Returning to fig. 1, the camera 12 is an imaging section 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 receives a control signal from the controller 90 to perform shooting. The camera 12 transmits the shooting result to the controller 90.

The plurality of mirrors 13 includes four mirrors 13a, 13b, 13c, and 13 d. The mirrors 13a, 13b, 13c, and 13d are optical elements such as prisms, for example. The mirrors 13a, 13b, 13c, and 13d are arranged to surround the workpiece W conveyed to the imaging area A2 when viewed from the Z direction (first direction), and reflect an image of the workpiece W toward the imaging surface of the camera 12. The mirrors 13a, 13b, 13c, and 13d are arranged at four corner portions of the workpiece W having a substantially rectangular shape when viewed from the Z direction, and reflect images of the corner portions. As shown in fig. 1, the mirrors 13a, 13b, 13c, and 13d are arranged at positions forming an angle of 45 ° with respect to the X direction and the Y direction when viewed from the Z direction. By providing the respective reflection mirrors 13a, 13b, 13c, and 13d in this way, the image of the workpiece W is reflected toward the imaging surface of the camera 12 with respect to two sides (two sides viewed in the Z direction) near the corner portion of the workpiece W.

The mirror opening/closing mechanism 14 is a moving mechanism configured to be able to open and close the plurality of mirrors 13a and 13 b. The mirror opening/closing mechanism 15 is a moving mechanism configured to be able to open and close the plurality of mirrors 13c and 13 d. The mirror opening/ closing mechanisms 14 and 15 perform opening/closing operations in response to a control signal from the controller 90.

Fig. 4 (a) and 4 (b) are diagrams illustrating the operation of the mirror opening/ closing mechanisms 14 and 15. As shown in fig. 4 (a) and 4 (b), the mirror opening/closing mechanism 14 includes: a driving portion 14a having a power source such as an actuator and movable in the Y direction; and a coupling portion 14b coupled to the driving portion 14a and to the mirrors 13a, 13 b. The mirror opening and closing mechanism 15 includes: a driving portion 15a having a power source such as an actuator and movable in the Y direction; and a coupling portion 15b coupled to the driving portion 15a and to the mirrors 13c and 13 d.

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

Fig. 4 (b) shows a state in which the driving units 14a and 15a move in the direction of the conveyance path (specifically, in the direction of the imaging region A2) in response to control from the controller 90. In this state, since the plurality of mirrors 13a, 13b, 13c, and 13d are arranged close to the workpiece W, the frame of the imaging time can be reduced to realize imaging of the workpiece W at high resolution (high pixels).

Returning to fig. 1, the first illumination 17 is an illumination that is disposed above the workpiece W conveyed to the imaging area A2 and irradiates the workpiece W with light. The second illuminations 18 and 19 are illuminations that are disposed below the workpiece W conveyed to the imaging region A2 and irradiate the workpiece W with light.

Fig. 5 is a diagram illustrating the first illumination 17 and the second illumination 18 and 19. As shown in fig. 5, the first illumination 17 is disposed below the camera 12 and above the workpiece W, and is formed in a ring shape so as not to block a gap between the camera 12 and the workpiece W. The second illumination 18 is disposed below the workpiece W (see fig. 5) and illuminates 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 disposed below the workpiece W (see fig. 5) to illuminate the surface of the workpiece W on the side of the image reflected by the plurality of mirrors 13c and 13d from below (see fig. 1). The second illuminations 18 and 19 can perform imaging without partial halo unevenness by, for example, using variable illuminations and irradiating the entire bottom surface of the workpiece W via the diffuser plate.

Fig. 6 is a diagram showing an example of the imaging result of the camera 12. As shown in fig. 6, the mirrors 13a, 13b, 13c, and 13d are arranged at positions at 45 ° angles with respect to the X direction and the Y direction so as to surround the workpiece W, and the imaging is performed in a state where the second illumination 18 and 19 irradiates light from below the workpiece W, whereby the inner R surface Wi of the workpiece W, two sides near the corner of the workpiece W, and the like can be appropriately imaged by the single camera 12.

Returning to fig. 1, the controller 90 is configured to be able to execute processing (control processing) for controlling each component included in the appearance inspection apparatus 1 and processing (determination processing) for determining the surface state of the workpiece W based on the inspection result, in order to inspect a predetermined inspection surface of the workpiece W. Next, the control process and the determination process will be described in detail.

In the control process, the controller 90 first controls the conveyor 11 to convey the workpiece W supported by the support portion 16 to the positioning area A1 along the conveying path and stop at the positioning area A1 (performs fifth control).

After the fifth control, as shown in fig. 3 (b), 3 (d), and the like, the controller 90 controls the positioning jig 20 to perform the positioning of the workpiece W in the Y direction in the positioning area A1 (sixth control is performed).

After the sixth control, as shown in fig. 3 (a), 3 (b), and the like, the controller 90 controls the conveyor 11 so that the workpiece W is conveyed to the imaging area A2 and stopped in the imaging area A2 (executes the first control).

After the first control, as shown in fig. 4 (b), the controller 90 controls the mirror opening/ closing mechanisms 14 and 15 to move the plurality of mirrors 13a, 13b, 13c, and 13d in the direction of the imaging area A2 (performs the second control).

After the above-described second control, the controller 90 controls the camera 12 to photograph the workpiece W (performs third control).

After the third control, the controller 90 controls the mirror opening/ closing mechanisms 14 and 15 to move the plurality of mirrors 13a, 13b, 13c, and 13d in a direction away from the conveyance path including the imaging region A2 (fourth control is executed).

In the determination process, the controller 90 determines whether or not the workpiece W is a good product based on the imaging result of the camera 12 in the third control (performs a seventh control). The controller 90 determines whether or not information such as the size, area, and color depth indicated by the imaging result of the camera 12 is within a predetermined normal range, for example. The controller 90 may determine whether or not the information such as the size, the area, and the color depth is normal (the same as the standard image) by comparing the imaging result of the camera 12 with the standard image, which is a good product image of the workpiece W. The defective items, such as scratches, cracks, pitting, and burrs, can be determined based on the size indicated by the imaging result of the camera 12. For example, the speckle can be determined based on the depth and area indicated by the imaging result of the camera 12. For example, the judgment can be made using the result of the image taken by the camera 12 for orange peel, polishing failure, and cutting failure. Specifically, the orange peel can be determined from the area indicated by the imaging result, the poor polishing can be determined from the width indicated by the imaging result, and the poor cutting can be determined from the size indicated by the imaging result.

The controller 90 may perform various determinations as to whether or not the workpiece W is good in a predetermined order, and may determine the workpiece W as a defective product without performing subsequent determinations as to whether or not the workpiece W is good at a time when any of the determinations as to whether or not the workpiece W is defective. The controller 90 may specify a defective item (e.g., orange peel) for the workpiece W determined to be defective, and may discharge the workpiece W determined to be defective to a discharge position for each defective item.

In addition, when determining whether or not the workpiece W is good, the controller 90 may determine whether or not the workpiece W is good after performing division correction processing for correcting the size by multiplying the reduction rate corresponding to the distance from the corner in the workpiece W.

Fig. 7 is a diagram illustrating the division correction processing. With respect to the periphery of the corner portion of the workpiece W, the actual size is estimated with high accuracy by dividing the area into five and multiplying each area by the reduction ratio. In the example shown in fig. 7, the corner peripheral region of the workpiece W is divided into 5. Specifically, two sides extending from the corner portion are divided into five regions including a region 3mm away from the corner portion of the workpiece W (3 mm in each of the two sides) and regions each dividing the remaining inspection region into two in each of the two sides, with the depth side (depth side as viewed from the corner portion) 3mm from the center of the workpiece W being the inspection region. In each of the divided regions, the regions may overlap by about 3mm, for example. Such a region divided into five is multiplied by a reduction ratio corresponding to the distance from the corner, and the size is estimated. Specifically, in the example shown in fig. 7, the size is estimated by multiplying the area 3mm from the corner by the reduction ratio of 98%, multiplying the area closer to the corner out of the two-divided areas by the reduction ratio of 94%, and multiplying the area closer to the center out of the two-divided areas by the reduction ratio of 82%. Such a reduction rate may be set based on the actual verification result. When a defect is detected in a region where the regions overlap, the defect may be multiplied by a smaller reduction ratio of the reduction ratios of the respective regions divided into two.

The hardware of the controller 90 is constituted by one or more control computers, for example. The controller 90 has a circuit 900 shown in fig. 8 as a hardware configuration, for example. 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 a driver 905. The processor 901 executes a program in accordance with at least one of the memory 902 and the storage device 903, and executes input/output of signals via the input/output port 904, thereby configuring the above-described functional blocks.

Further, the hardware configuration of the controller 90 is not necessarily limited to the functional blocks configured by the execution of the program. For example, the controller 90 may be formed of a dedicated logic Circuit or an ASIC (Application Specific Integrated Circuit) Integrated therewith.

Next, the appearance inspection process (appearance inspection method) of the workpiece W performed by the appearance inspection apparatus 1 will be described with reference to fig. 9.

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

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

Then, a camera inspection is performed to photograph the workpiece W with the camera 12 (step S6, third step). Thereafter, the mirror opening/ closing mechanisms 14 and 15 perform mirror opening/closing movement 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, fourth step).

Then, a determination is made as to whether or not the workpiece W is good by the camera inspection (step S8), and the workpiece W that is a poor product is discharged as a poor product (step S9), and the workpiece W that is a good product is discharged as a good product (step S10).

Next, the operation and effects of the appearance inspection device 1 of the present embodiment will be described.

The appearance inspection apparatus 1 of the present embodiment is an appearance inspection apparatus for inspecting a surface state of a workpiece W, and includes: a conveyor 11 configured to be capable of conveying the placed workpiece W to the imaging area A2 along a conveying path; a camera 12 which faces the workpiece W conveyed to the imaging area A2 in the Z direction and images the workpiece W; a plurality of mirrors 13a, 13b, 13c, and 13d arranged to surround the workpiece W conveyed to the imaging area A2 when viewed from the Z direction, and reflecting an image of the workpiece W toward an imaging surface of the camera 12; mirror opening/closing mechanisms 14 and 15 configured to be able to move the plurality of mirrors 13a, 13b, 13c, and 13d; and a controller 90, the controller 90 being configured to be able to execute the following control: a first control of controlling the conveyor 11 to convey the workpiece W to the imaging area A2 and stop at the imaging area A2; a second control of controlling the mirror opening/closing mechanisms 14 and 15 to move the plurality of mirrors 13a, 13b, 13c, and 13d in the direction of the imaging area A2 after the first control; a third control of controlling the camera 12 to photograph the workpiece W after the second control; the fourth control is to control the mirror opening/closing mechanisms 14 and 15 to move the plurality of mirrors 13a, 13b, 13c, and 13d in a direction away from the conveyance path including the imaging region A2 after the third control.

In the appearance inspection apparatus 1 of the present embodiment, since the plurality of mirrors 13a, 13b, 13c, and 13d that reflect the image of the workpiece W toward the imaging surface of the camera 12 are arranged so as to surround the workpiece W conveyed to the imaging area, it is possible to image a plurality of surfaces of the workpiece W by one camera 12, for example, the cost is reduced compared to a configuration in which an imaging unit is provided for each surface of the workpiece W, and switching of the imaging unit is not necessary, thereby simplifying the imaging process. In the appearance inspection apparatus 1 of the present embodiment, the mirror opening/ closing mechanisms 14 and 15 are controlled so that the plurality of mirrors 13a, 13b, 13c, and 13d are moved in the direction of the imaging area A2 in a state where the workpiece W is stopped in the imaging area A2, and thereafter, the camera 12 captures the workpiece W. In this way, by moving the plurality of mirrors 13a, 13b, 13c, and 13d in the direction of the imaging area A2 and performing imaging of the workpiece W in this state, imaging of the workpiece W is performed in a state where the plurality of mirrors 13a, 13b, 13c, and 13d are close to the workpiece W and the imaging frame is reduced in size when imaging the workpiece W, and therefore, imaging of the workpiece W at high resolution (high pixel) can be achieved. Further, in the appearance inspection apparatus 1 of the present embodiment, since the plurality of mirrors 13a, 13b, 13c, and 13d are moved in the direction away from the conveyance path including the imaging area A2 after the imaging, the plurality of mirrors 13a, 13b, 13c, and 13d are not arranged in the conveyance path except during the imaging (before and after the imaging), and the plurality of mirrors 13a, 13b, 13c, and 13d do not interfere with the conveyance of the workpiece W. As described above, according to the appearance inspection apparatus 1 of the present embodiment, the controller 90 moves the plurality of mirrors 13a, 13b, 13c, and 13d by the mirror opening/ closing mechanisms 14 and 15, thereby making it possible to capture an image of the workpiece W at high resolution while ensuring the transportability of the workpiece W.

The appearance inspection device 1 further includes a support portion 16 for supporting the workpiece W conveyed to the imaging area A2, at least a lower surface of the workpiece W is formed in an arcuate shape, and a surface of the support portion 16 for supporting 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 the arcuate 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 member, when the support portion 16 receives the workpiece W, the workpiece W can be efficiently prevented from being placed on the support portion 16 in a state where the workpiece W is displaced in the direction of the θ angle with respect to the axis of the support portion 16.

The appearance inspection apparatus 1 may further include a positioning jig 20 for positioning the workpiece W conveyed to the positioning area A1 on the upstream side of the imaging area A2 in the conveying path while holding the workpiece W from above, and the controller 90 may be configured to be capable of performing the following control: a fifth control of controlling the conveyor 11 to convey the workpiece W to the positioning area A1 and stop at the positioning area A1, prior to the first control; and a sixth control of controlling the positioning jig 20 so that the workpiece W is held down after the fifth control and before the first control. When the position (orientation) of the workpiece W conveyed to the imaging area A2 is different from the assumed position, the inspection of the workpiece W after imaging may not be performed with high accuracy. For the position correction of the workpiece W, for example, it is conceivable to perform the position correction by using image software, but even if such position correction is performed, the inspection accuracy of the workpiece W may not be sufficiently ensured. In this respect, by holding the workpiece W by the positioning jig 20 in the positioning area A1 on the upstream side of the imaging area A2 and performing positioning of the workpiece W in the front-rear direction (that is, actually performing position correction of the workpiece W instead of correction of the software), the inspection accuracy based on the imaging result of the subsequent imaging area A2 can be improved. Specifically, by pressing the workpiece W from above with the positioning jig 20, rolling misalignment of the workpiece W (misalignment in the direction in which the arched workpiece W rotates) can be corrected, and by positioning the workpiece W in the front-rear direction with the positioning jig 20, front-rear misalignment of the workpiece W can be corrected, and inspection accuracy can be improved.

The workpiece W has a substantially rectangular shape when viewed from the Z direction, and the plurality of mirrors 13a, 13b, 13c, and 13d may include four mirrors 13a, 13b, 13c, and 13d respectively arranged at four corner portions of the workpiece W when viewed from the Z direction, and reflect images of the corner portions. Since the mirrors 13a, 13b, 13c, and 13d are arranged at the corner portions in this manner, two sides close to the corner portions (two sides viewed in the Z direction) can be imaged by the mirrors 13a, 13b, 13c, and 13d, and thus each surface of the workpiece W can be appropriately imaged.

The controller 90 is configured to be able to execute seventh control for determining whether or not the workpiece W is good based on the imaging result of the camera 12 in the third control, and in the seventh control, after performing correction processing for correcting the size by multiplying the reduction rate corresponding to the distance from the corner in the workpiece W, it is determined whether or not the workpiece W is good. By performing such correction processing, the actual dimension can be estimated with high accuracy in consideration of the distance from the corner portion, and the accuracy of determining whether or not the workpiece W is good can be improved.

The appearance inspection apparatus 1 may further include: a first illumination 17 which is arranged above the workpiece W conveyed to the imaging area A2 and irradiates the workpiece W with light; and second illuminators 18 and 19 disposed below the workpiece W conveyed to the imaging area A2 and configured to irradiate the workpiece W with light. By providing the second illuminators 18 and 19 for irradiating light from below the workpiece W in addition to the first illuminator 17 for irradiating light from above the workpiece W, light can be appropriately irradiated to the lower surface (bottom surface) of the workpiece W which is difficult to irradiate light only by the first illuminator 17, and an imaging result which can more easily improve inspection accuracy can be obtained.

Description of the reference numerals

1 \8230, an appearance inspection device 11 \8230, a conveyor (conveying section) 12 \8230, a camera (image pickup section) 13a, 13b, 13c, 13d \8230, a mirror 14, 15 \8230, a mirror opening and closing mechanism (moving mechanism) 16 \8230, a support section 17 \8230, a first illumination 18, 19 \8230, a second illumination 20 \8230, a positioning jig (pressing jig) 90 \8230, a controller (control device) A1 \8230, a positioning area A2 \8230, an image pickup area W \8230, and a workpiece (component).

Claims (7)

1. An appearance inspection device for inspecting a surface state of a component, comprising:

a conveying unit configured to convey the mounted component to an imaging area along a conveying path;

an imaging unit that is opposed to the component conveyed to the imaging region in a first direction and that images the component;

a plurality of mirrors which are disposed so as to surround the member conveyed to the imaging region when viewed from the first direction, and which reflect an image of the member toward an imaging surface of the imaging unit;

a moving mechanism configured to be able to move the plurality of mirrors; and

a control device for controlling the operation of the motor,

the control device is configured to be capable of executing the following control:

a first control of controlling the conveying unit to convey the component to the imaging region and stop the component in the imaging region;

a second control of controlling the moving mechanism to move the plurality of mirrors in a direction of the imaging area after the first control;

a third control of controlling the image pickup section to pick up the component after the second control; and

and fourth control of controlling the moving mechanism to move the plurality of mirrors in a direction away from the transport path including the imaging region after the third control.

2. The visual inspection device according to claim 1,

further comprising a support portion for supporting the member transported to the imaging region,

the member is formed in an arch shape at least at a lower face thereof,

the surface of the support portion supporting the member is formed in a V-shape with a center portion recessed downward so as to correspond to the shape of the member formed in an arch shape.

3. The appearance inspection device according to claim 2,

a pressing jig that presses the member conveyed to a positioning region on an upstream side of the imaging region in the conveyance path from above and performs positioning in a front-rear direction,

the control device is configured to be capable of executing the following control:

a fifth control of controlling the conveying section to convey the component to the positioning area and stop the component at the positioning area, prior to the first control; and

a sixth control that controls the pressing jig so that the component is pressed after the fifth control and before the first control.

4. The visual inspection device according to any one of claims 1 to 3,

the member is substantially rectangular in shape when viewed from the first direction,

the plurality of mirrors includes four mirrors which are respectively arranged at four corner portions of the member when viewed from the first direction, and reflect images of the corner portions.

5. The visual inspection device according to claim 4,

the control device is configured to be capable of executing seventh control for determining whether or not the component is a good component based on the imaging result of the imaging unit in the third control,

in the seventh control, after a correction process of correcting the dimensions by multiplying the reduction rate corresponding to the distance from the corner portion in the component is performed, it is determined whether or not the component is a good product.

6. The appearance inspection device according to any one of claims 1 to 5, further comprising:

a first illumination unit that is disposed above the component transported to the imaging region and irradiates the component with light; and

and a second illumination unit which is disposed below the component transported to the imaging region and irradiates the component with light.

7. An appearance inspection method of inspecting a surface state of a component, comprising:

a first step of conveying a component to an imaging region by a conveying unit and stopping the component in the imaging region;

a second step of moving, by a moving mechanism, a plurality of mirrors arranged so as to surround the member transported to the imaging area in a direction of the imaging area after the first step;

a third step of, after the second step, imaging the component by an imaging unit; and

a fourth step of moving the plurality of mirrors in a direction away from the imaging region by the moving mechanism after the third step.

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