Component mounting device

Abstract

To reliably conduct component inspection conducted before mounting on a substrate.SOLUTION: A surface mounting machine 1 includes: a head 4H that holds a component C and mounts it on a substrate P; a multi-camera 11 that picks up an image of the component C held by the head 4H to acquire a two-dimensional image of the component C; a TOF camera 12 that irradiates the component C with measurement light L1, and acquires three-dimensional information of the component C on the basis of the time until reflected light L2 from the component is obtained; and a control unit 8. The control unit 8 includes: a correction processing section 842 that, on the basis of the three-dimensional information of the component C, specifies, on an imaging optical axis AX, a background area AR2 located on a depth side compared to an inspection target area AR1 determined in advance for the component C, and performs image processing of removing the background area AR2 on the two-dimensional image IM1 of the component C; and a determination section 843 that conducts required inspection about the component C on the basis of the two-dimensional image IM2 of the component C on which the image processing is performed.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a component mounting apparatus equipped with a head that holds a component and mounts it on a board. [Background technology]

[0002] A component mounting device that mounts electronic components on a printed circuit board is equipped with a head that picks up and holds the components. The component mounting device is also equipped with an inspection device that acquires a two-dimensional image of the head that has undergone the component pick-up process and performs component recognition to inspect the component holding posture by the head, component pick-up errors, and the condition of the component itself (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-2579 Summary of the Invention [Problem to be solved by the invention]

[0004] Depending on the type of component, it can be difficult to recognize the component using an image. For example, this can occur when a component piece that appears bright in the image is located at the back of the inspection target along the imaging optical axis. In this case, the component piece is reflected in the background of the inspection target, making it impossible to identify the inspection target in the image. This requires that the area with the bright component piece be excluded from the inspection target, reducing inspection accuracy. Alternatively, a separate inspection of the excluded part is required, increasing the inspection man-hours.

[0005] An object of the present invention is to provide a component mounting apparatus that can reliably perform component inspection before mounting on a board. [Means for solving the problem]

[0006] A component mounting apparatus according to one aspect of the present invention comprises a head that holds components and mounts them on a board; an image acquisition unit that images the components held in the head and acquires two-dimensional images of the components; a three-dimensional measurement unit that irradiates measurement light onto the components held in the head and acquires three-dimensional information about the components based on the time it takes for reflected light from the components to be obtained; a correction processing unit that, based on the three-dimensional information about the components, identifies a background area that is located behind a predetermined inspection target area for the components on the imaging optical axis of the image acquisition unit and performs image processing on the two-dimensional image of the components to remove the background area; and an inspection unit that performs the required inspection of the components based on the two-dimensional image of the components that has been subjected to the image processing.

[0007] According to this aspect, a background area located behind the inspection target area of the component is identified based on the three-dimensional information, and image processing is performed to remove the background area. Therefore, even if a component piece or the like that reduces inspection accuracy appears in the background of the inspection target area in the two-dimensional inspection image, the influence of the background can be eliminated. Therefore, the inspection target area can be inspected reliably.

[0008] In the component mounting apparatus, the component may be an electronic component having terminals, and the inspection target area may be an area of the component where the terminals are present.

[0009] If the terminals are deformed, such as lifted, they are more likely to cause mounting errors on the board, so it is important to accurately recognize the terminals in an image. According to the above aspect, if a background that reduces the recognition accuracy of the terminals is captured in the two-dimensional image, removing such background can improve the recognition accuracy of the terminals, thereby increasing the reliability of the inspection.

[0010] In the component mounting apparatus, it is desirable that the correction processing unit removes the inner side of the area located around the terminal in the direction in which the imaging optical axis extends.

[0011] According to this aspect, the background is removed from the area behind the terminal, thereby improving the accuracy of terminal recognition with minimal image processing.

[0012] It is desirable that the component mounting apparatus further comprises a storage unit that stores component data relating to the shape of the component, and that the correction processing unit distinguishes between the inspection target region and the background region based on the component data.

[0013] According to this aspect, the background region can be easily and reliably identified by referencing the component data. Therefore, the inspection target region and the background region can be accurately distinguished, and the background region can be removed. Therefore, the accuracy of recognizing the inspection target region can be improved.

[0014] In the component mounting apparatus, it is preferable that the correction processing unit performs image processing to replace pixels in the portion of the two-dimensional image that is identified as the background region with black.

[0015] According to this aspect, the image processing for removing the background region in the correction processing section can be simplified, and the processing speed can be increased.

[0016] The above-mentioned component mounting device may be provided with a TOF camera capable of acquiring two-dimensional images including height information, wherein the image acquisition unit uses the two-dimensional image acquisition function of the TOF camera, and the three-dimensional measurement unit uses the height information acquisition function of the TOF camera.

[0017] When a part is captured with a TOF (Time Of Flight) camera, not only is a two-dimensional image of the part obtained, but three-dimensional information about the part can be obtained based on the time from when the measurement light is emitted to when the reflected light is received. Therefore, a TOF camera alone can function as both an image acquisition unit and a three-dimensional measurement unit.

[0018] The above-mentioned component mounting device may further include a TOF camera capable of acquiring three-dimensional information of the component, wherein the image acquisition unit is a component recognition camera that captures an image of the component from below to acquire a two-dimensional image, and the correction processing unit performs image processing on the two-dimensional image acquired by the component recognition camera based on the three-dimensional information acquired by the TOF camera.

[0019] According to this aspect, the background area can be identified based on the three-dimensional information acquired by the TOF camera from the two-dimensional image acquired by the component recognition camera normally equipped in the component mounting device. Therefore, simply by adding a TOF camera to an existing component mounting device, the background area removal function can be added. [Effects of the Invention]

[0020] According to the present invention, it is possible to provide a component mounting apparatus that can reliably perform component inspection before mounting on a board. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a plan view showing a schematic configuration of a surface mounter according to a first embodiment, as an example of a component mounting apparatus of the present invention. [Figure 2] FIG. 2 is a side view showing a schematic configuration of a head unit portion of the surface mounter. [Figure 3] FIG. 3 is a block diagram showing a schematic configuration of the TOF camera. [Figure 4] FIG. 4 is a block diagram showing the electrical configuration of the surface mounter. [Figure 5] FIG. 5(A) is a perspective view showing an example of a component with terminals, and FIG. 5(B) is a diagram showing a two-dimensional image captured for recognition of the component with terminals. [Figure 6] FIG. 6 is a side view for explaining the inspection target area and background area of the component. [Figure 7] FIG. 7 is a flowchart showing component mounting control by the surface mounter of the first embodiment. [Figure 8]Figure 8(A) is a diagram showing three-dimensional information of the part in Figure 5(A), Figure 8(B) is a diagram showing a two-dimensional image of the part before background removal correction processing is performed, and Figure 8(C) is a diagram showing a two-dimensional image of the part after background removal correction processing is performed. [Figure 9] FIG. 9 is a plan view showing a schematic configuration of a surface mounter according to the second embodiment. [Figure 10] FIG. 10 is a flowchart showing component mounting control by the surface mounter of the second embodiment. [Figure 11] Figure 11(A) is a diagram showing three-dimensional information of the part in Figure 5(A), Figure 11(B) is a diagram showing a two-dimensional IR image of the part acquired by a TOF camera, and Figure 11(C) is a diagram showing a two-dimensional IR image of the part after background removal correction processing has been performed. DETAILED DESCRIPTION OF THE INVENTION

[0022] Embodiments of a component mounting apparatus according to the present invention will be described in detail below with reference to the drawings. In the embodiments described below, a surface mounter is shown as an example of a component mounting apparatus. The surface mounter is an apparatus that mounts various components on a printed circuit board. The components include, for example, chip components such as chip resistors and chip capacitors, IC package electronic components such as BGA, QFP, or SOP, power supply-related components such as capacitors and transformers, connectors, and heat sinks. Note that the component mounting apparatus according to the present invention is not limited to surface mounters, and can also be applied to other component holding devices and component moving devices that have heads. The components held by the heads may be mechanical components or molded components made of metal, resin, rubber, wood, etc.

[0023] [Overall structure of surface mounter / first embodiment] Fig. 1 is a plan view showing the configuration of a surface mounter 1 of the first embodiment, and Fig. 2 is a side view showing the schematic configuration of a head unit 4 portion of the surface mounter 1. The surface mounter 1 is a device that mounts various electronic components on a substrate P. Directional indications of XYZ are provided in Figs. 1 and 2, and similar direction indications are provided in other figures. The X direction is the direction of movement of the substrate P. Note that the X direction may also be referred to as the left-right direction, the Y direction as the front-rear direction, and the Z direction as the up-down direction.

[0024] The surface mounter 1 includes a base unit 10, a board transport unit 2, a component supply unit 3, a head unit 4, a multi-camera 11 (image acquisition unit), and a TOF camera 12 (three-dimensional measurement unit) that are arranged on the base unit 10. The head unit 4 is equipped with a board recognition camera 5 and a scan camera unit 6.

[0025] The base unit 10 is a rectangular base with a flat top surface, and has a board transport unit 2 and a component supply unit 3 attached to it. The board transport unit 2 transports a board P on which components C are to be mounted. The board transport unit 2 has a pair of conveyors 21 and 22 on the base unit 10 that transport the board P left and right. The conveyors 21 and 22 transport the board P into the surface mounter 1 from the right side, and then transport it leftward to a predetermined work position, here the position of the board P shown in FIG. 1, where it stops temporarily. At this work position, components C are mounted on the board P. After the mounting operation, the conveyors 21 and 22 transport the board P leftward and out of the surface mounter 1.

[0026] The component supply units 3 supply components C to be mounted on the board P. The component supply units 3 are arranged on both front and rear sides of the board transport unit 2. Each component supply unit 3 has a plurality of tape feeders 31 arranged in the left-right direction. Each tape feeder 31 is equipped with a reel around which a tape is wound, which stores and holds electronic components such as ICs, transistors, resistors, and capacitors at predetermined intervals. The tape feeders 31 intermittently pay out the tape from the reel and supply the components C to the component supply position at the tip of the feeder. Although a tape feeder 31 is shown here as an example, a tray on which large electronic components or other components are placed may also be attached to the component supply unit 3.

[0027] The head unit 4 takes out a component C from the component supply unit 3 and mounts it on the substrate P. The head unit 4 is arranged above the base unit 10 so as to be movable in the X and Y directions, takes out a component C from the tape feeder 31 at the component supply position, and mounts the component C at a predetermined position on the substrate P at the work position. A support beam 23 extending in the X direction is erected above the base unit 10. The head unit 4 is movably supported on an X-axis fixed rail 24 fixed to the support beam 23.

[0028] Both ends of support beam 23 are supported by Y-axis fixed rails 25 extending in the Y direction, and support beam 23 is movable in the Y direction along these Y-axis fixed rails 25. An X-axis servo motor 26 and a ball screw shaft 27 are disposed relative to X-axis fixed rail 24. A Y-axis servo motor 28 and a ball screw shaft 29 are disposed relative to Y-axis fixed rail 25. Head unit 4 moves in the X direction as ball screw shaft 27 is rotationally driven by X-axis servo motor 26, and moves in the Y direction as ball screw shaft 29 is rotationally driven by Y-axis servo motor 28.

[0029] The head unit 4 is equipped with a plurality of heads 4H for holding and transporting components C. In this embodiment, an example is shown in which a total of six heads 4H are arranged in a row in the X direction. Each head 4H includes a shaft 41 extending in the Z direction and a suction nozzle 42 attached to the lower end of the shaft 41. The shaft 41 can move up and down relative to the head unit 4 and rotate around the nozzle central axis (R axis). The suction nozzle 42 picks up and holds the component C and mounts it on the surface of the substrate P.

[0030] The board recognition cameras 5 are fixedly mounted on both the left and right sides of the head unit 4. The board recognition cameras 5 capture images of various marks attached to the surface of the board P that has been carried into the work position of the surface mounter 1 by the conveyors 21 and 22. In FIG. 1, as an example of the marks, a pair of fiducial marks FM attached on the diagonal of the rectangular board P is shown. The fiducial marks FM are marks for detecting the amount of positional deviation of the carried-in board P from the origin coordinates of the work position.

[0031] The scan camera unit 6 is mounted near the bottom end of the head unit 4 and is movable in the X direction relative to the head unit 4. The scan camera unit 6 is a unit for image recognition of the state of holding of the component C by the suction nozzle 42. The scan camera unit 6 includes a scan camera 62 (image acquisition unit) that captures an image of the component held by the suction nozzle 42. The scan camera 62 performs a predetermined imaging operation while the head unit 4 transports the component C picked up by the suction nozzle 42 from the component supply position to the work position. The scan camera unit 6 moves in the X direction along a ball screw shaft 61 attached to the head unit 4 and extending in the X direction. While the scan camera unit 6 moves in the X direction during the transport of the component C, the scan camera 62 captures an image of the component C picked up by the suction nozzle 42. The scan camera 62 can capture a bottom view of the component C picked up by the suction nozzle 42 from vertically below and a side view of the component C picked up from the side.

[0032] The multi-camera 11 is a component recognition camera that captures two-dimensional images of the component C, and is incorporated into the base unit 10. The multi-camera 11 has an imaging field of view above the base unit 10, and captures images of the component C held by the suction nozzles 42 of the head 4H from the bottom side. The two-dimensional images captured by the multi-camera 11 are also used for image recognition of the state of the component C held by the suction nozzles 42. For example, the multi-camera 11 is used to recognize large components, and the scan camera 62 is used to recognize small components.

[0033] The TOF camera 12 is a camera capable of acquiring two-dimensional images including height information. The TOF camera 12 is incorporated into the base unit 10 at a position adjacent to the multi-camera 11. The TOF camera 12 functions as a three-dimensional measurement unit that irradiates measurement light onto the component C held by the head 4H and acquires three-dimensional information of the component C based on the time it takes for reflected light from the component C to be obtained.

[0034] FIG. 3 is a block diagram showing the schematic configuration of the TOF camera 12. The TOF camera 12 includes an illumination unit 13, a light-receiving unit 14, and a measurement processing unit 15. The illumination unit 13 has a light source such as a semiconductor laser or an LED, and irradiates the test component CA with measurement light L1. The measurement light L1 is near-infrared light having a wavelength of, for example, about 850 nm. The light-receiving unit 14 receives reflected light L2 of the measurement light L1 from the test component CA. The light-receiving unit 14 is a camera device and includes a lens unit 141, an image sensor 142 such as a CMOS sensor, and the measurement processing unit 15.

[0035] The lens unit 141 forms an optical image of the reflected light L2 on the light receiving surface of the image sensor 142. The image sensor 142 is a sensor that photoelectrically converts the reflected light L2. When the measurement light L1 is infrared (IR) light, the image sensor 142 captures a two-dimensional IR image, which is an infrared image. The image sensor 142 is also capable of measuring time on a pixel-by-pixel basis. The measurement processing unit 15 is a processor that converts the pixel data of the image sensor 142, including the time element, into distance information, that is, into three-dimensional information of the test component CA. The measurement processing unit 15 obtains, from the pixel data, the time Δt from the time t1 when the measurement light L1 is emitted from the illumination unit 13 to the time t2 when the reflected light L2 is received by the image sensor 142. The distance d to the test component CA can be calculated as d = C × Δt / 2, where C is the speed of light. That is, the TOF camera 12 can acquire a two-dimensional IR image of the test piece CA and information on the distance d to the test piece CA that is the subject of the image capture, that is, height data.

[0036] [Control configuration] 4 is a block diagram showing the electrical configuration of the surface mounter 1. In addition to the configuration described above, the surface mounter 1 is equipped with a Z-axis servo motor 71, an R-axis servo motor 72, a camera axis servo motor 73, a control unit 8, and an operation unit 87. The Z-axis servo motor 71 is a drive source that raises and lowers the head 4H. The R-axis servo motor 72 is a drive source that rotates the head 4H around its axis. The camera axis servo motor 73 is a drive source that moves the scan camera unit 6 in the X direction.

[0037] The control unit 8 comprises a processor and the like that operates by loading a predetermined program, and functionally comprises an axis control unit 81, an imaging control unit 82, an image processing unit 83, an inspection processing unit 84, a memory unit 85, and an overall control unit 86.

[0038] The axis control unit 81 controls various servo motors to control the movement of the head unit 4 in the X and Y directions, the elevation (movement in the Z direction) and rotational movement (R-axis rotation) of the head 4H, and the movement of the scan camera unit 6 in the X direction.

[0039] The imaging control unit 82 controls the operation of various cameras equipped in the surface mounter 1. Specifically, the imaging control unit 82 operates the board recognition camera 5 at a predetermined timing to capture an image of the fiducial mark FM on the board P. The imaging control unit 82 operates the multi-camera 11 and the scan camera 62 at a predetermined timing to capture an image of the head 4H that has picked up the component C and acquire a two-dimensional image for component recognition. Furthermore, the imaging control unit 82 operates the TOF camera 12 at a timing when the head 4H that has picked up the component C passes above the TOF camera 12 to perform imaging to acquire three-dimensional information about the component C.

[0040] The image processing unit 83 performs necessary image processing such as contrast and brightness correction, noise removal, edge extraction, etc. on the image data of the component C acquired by the board recognition camera 5, the scan camera 62, the multi-camera 11, and the TOF camera 12. The image processing unit 83 includes an image memory 831 that temporarily stores the image data sent from each camera.

[0041] The inspection processing unit 84 performs required inspection processing on the component C held by the suction nozzle 42 based on images acquired by the scan camera 62, the multi-camera 11, and the TOF camera 12. The inspection processing unit 84 reads image data of the component C from the image memory 831 and performs the inspection processing. The inspection processing unit 84 functionally includes an area specifying unit 841, a correction processing unit 842, and a determination unit 843 (inspection unit).

[0042] The region identification unit 841 identifies a background region in a two-dimensional image of the component C acquired by the multi-camera 11 or the scan camera 62, based on the three-dimensional information of the component C acquired by the TOF camera 12. The background region is a region located on the imaging optical axis of the multi-camera 11 or the scan camera 62, further from the camera than a predetermined inspection target region. The inspection target region is set for each component C according to the shape and type of the component C. For example, if the component C has terminals such as leads or ball electrodes, the region where the terminals exist is set as the inspection target region, and the presence or absence of floating or missing terminals is inspected.

[0043] The correction processing unit 842 performs image processing to remove the background region identified by the region identification unit 841 from the two-dimensional image of the component C. This image processing is processing to clarify the contrast between the background region and the region to be inspected, for example, by replacing the pixels in the part of the two-dimensional image identified as the background region with black. Note that in the case of component C for which background removal is not required, the identification of the background region by the region identification unit 841 and the image processing by the correction processing unit 842 are skipped.

[0044] The determination unit 843 performs a required inspection of the component C as a component recognition inspection based on the two-dimensional image of the component C. The required inspection is, for example, an inspection to detect an abnormality in the suction posture of the component C by the suction nozzle 42, an error in suction of the component C, or defects in the component C itself, such as floating or missing terminals. The determination unit 843 determines whether or not the component C held by the suction nozzle 42 can be mounted on the board P based on predetermined criteria.

[0045] The storage unit 85 stores various information related to the substrate P and the components C, various setting values and parameters related to the surface mounter 1, control data, operation programs, etc. As information about the components C, component data related to the shapes of the components C is stored in the storage unit 85. The area identification unit 841 distinguishes between an inspection target area and a background area based on the component data.

[0046] The overall control unit 86 comprehensively controls various operations of the surface mounter 1. For example, the overall control unit 86 provides control signals to the axis control unit 81, the imaging control unit 82, the inspection processing unit 84, etc., causing them to perform operations such as driving the head unit 4 and the head 4H, causing various cameras to capture images, and performing image processing on image data.

[0047] [The significance of background removal] 5A shows an example of a component that requires the correction processing unit 842 to remove a background region. FIG. 5A is a perspective view of an example of a component 9 with terminals, viewed from the bottom. The component 9 includes a rectangular parallelepiped component body 91, terminals 92A and 92B extending from the lower ends of a pair of opposing side surfaces of the component body 91, and a lever 93 extending from the same side surface above one of the terminals 92A. The component body 91 is dark in color, while the lever 93 is whitish in color. The terminals 92A and 92B have a metallic luster.

[0048] In such a component 9, in addition to the external shape of the component body 91, the condition of the terminals 92A, 92B that will come into contact with the board P is inspected. This is because if there is any defect in the condition of the terminals 92A, 92B, there is a high possibility of a mounting error occurring. Specifically, the terminals 92A, 92B are inspected to see if their positions are within the normal range, if they are missing, if they are deformed, etc. For this inspection, at least an image of the component 9 viewed from the bottom is acquired.

[0049] FIG. 5B shows a two-dimensional image IM of the underside of component 9 captured by the multi-camera 11 or scan camera 62 for component recognition. Terminals 92A and 92B, which have a metallic luster, appear in the two-dimensional image IM as high-brightness areas when illuminated with illumination light. A whitish lever 93 also appears in the two-dimensional image IM as a high-brightness area. One terminal 92A and lever 93 are positioned so that they overlap in the height direction of component 9. Therefore, in the two-dimensional image IM, the high-brightness lever 93 is reflected in the background of terminal 92A. In other words, terminal 92A and lever 93 blend together in the image, making it impossible to accurately recognize the shape of terminal 92A.

[0050] In this case, the area in which the lever 93 is reflected must be excluded from the inspection target, which reduces the inspection accuracy for the component 9. Alternatively, a separate inspection of the terminal 92A is required, which increases the number of inspection steps. To resolve this problem, the inspection processing unit 84 identifies the inspection target area of the component 9, in which the terminal 92A that requires inspection is located, and the background area in which the lever 93 is reflected, based on the three-dimensional information of the component 9, and then performs processing to remove the background area.

[0051] The inspection target area and background area will be further described with reference to FIG. 6. FIG. 6 illustrates a leaded component 9A held by suction nozzle 42. Leaded component 9A includes a rectangular parallelepiped component body 91A, a first lead 921 (terminal) extending from the bottom edge of the left side of component body 91A, a second lead 922 (terminal) extending from the bottom edge of the right side, and a whitish component piece 93A. A two-dimensional image for component recognition of leaded component 9A is captured from the bottom side of component 9A, as indicated by imaging optical axis AX. Component piece 93A is positioned so as to overlap second lead 922 on imaging optical axis AX.

[0052] In the leaded component 9A, the first lead 921 and the second lead 922 are particularly subject to inspection. On the other hand, the component piece 93A does not require any special recognition processing. In this case, the height region where the leads 921 and 922 exist is the inspection target region AR1, and the height region where the component piece 93A exists is the background region AR2. Specifically, the inspection target region AR1 extends from height h0 of the bonding surface 94, which is the lower end surface of the first lead 921 and the second lead 922, to height h1 immediately adjacent to the lower surface of the component piece 93A. Furthermore, the region behind the inspection target region AR1, i.e., from height h1 to height h2 of the upper surface of the component body 91A, is the background region AR2. Note that it is not necessary to set an upper limit height for the background region AR2.

[0053] The height of each portion of the leaded component 9A held by the suction nozzle 42 is derived based on the three-dimensional information acquired by the TOF camera 12. Meanwhile, the memory unit 85 stores component data related to the shape of the leaded component 9A. For example, the memory unit 85 stores height data for the underside of the component piece 93A, based on the bonding surface 94 (height = h0) of the leads 921, 922. Referring to this height data, the region identification unit 841 sets a threshold height h1 that separates the inspection target region AR1 from the background region AR2. Furthermore, the region identification unit 841 identifies the inspection target region AR1 and the background region AR2 based on whether the height of each portion of the component 9A obtained from the three-dimensional information from the TOF camera 12 exceeds the threshold height h1.

[0054] The correction processing unit 842 performs image processing to remove the area identified as the background area AR2 from the two-dimensional image of the leaded component 9A acquired for component recognition. For example, image processing to replace the pixels constituting the background area AR2 with black is performed. This image processing causes the high-brightness component piece 93A to be painted black in the two-dimensional image, making the outline of the second lead 922 clear. Note that the background area AR2 may be removed entirely, or only the background area behind the area surrounding the second lead 922 may be partially removed. The fact that the component piece 93A is reflected in the background of the second lead 922 can be predicted in advance from component data, etc. In the example of FIG. 6, it is sufficient to remove only the background surrounding the second lead 922. This improves the recognition accuracy of the second lead 922 with minimal image processing.

[0055] [Component Mounting Control Example of First Embodiment] 7 is a flowchart showing component mounting control by the surface mounter 1 of the first embodiment. Components are sequentially picked up by the suction nozzles 42 of the head 4H in accordance with a mounting sequence controlled by the overall control unit 86. Referring also to FIGS. 1 and 4, the inspection processing unit 84 acquires component data for the component C to be picked up in the current turn from the storage unit 85 (step S1).

[0056] The axis control unit 81 controls the X-axis servo motor 26 and the Y-axis servo motor 28 to move the head unit 4 toward a specific component supply position of the component supply unit 3 that supplies the component C to be picked up this time, i.e., toward a specific tape feeder 31 (step S2). When the head unit 4 reaches the component supply position, the axis control unit 81 controls the Z-axis servo motor 71 and, if necessary, the R-axis servo motor 72 to pick up the component C with the suction nozzle 42 (step S3).

[0057] Next, the inspection processing unit 84 determines whether the picked-up component C is a component that requires image processing to remove the background area AR2, based on the component data acquired in step S1 (step S4). If the inspection processing unit 84 determines that the component C requires background removal processing (YES in step S4), the axis control unit 81 moves the head unit 4 so that the head 4H holding the component C passes above the TOF camera 12 (step S5). When the head 4H reaches the TOF camera 12, the imaging control unit 82 causes the TOF camera 12 to perform an imaging operation and acquire an image of the component C picked up by the suction nozzle 42 (step S6). The acquired image data including the three-dimensional information is stored in the image memory 831.

[0058] FIG. 8A shows the three-dimensional information HD when the component 9 with terminals shown in FIG. 5A is the subject of imaging in step S6. In the three-dimensional information HD, the grid arranged in a matrix in the X and Y directions represents the pixels Px of the imaging element 142 (FIG. 3) of the TOF camera 12. The numbers written in the pixels Px represent height data. Height = 0 represents the height of the reference portion of the component 9. In the component 9, this corresponds to the height of the bottom surfaces of the terminals 92A and 92B. For the component 9A shown in FIG. 6, the position of height = 0 corresponds to the height h0 of the bonding surface 94 of the leads 921 and 922. The larger the number of the pixel Px, the further back the pixel is located on the imaging optical axis AX, i.e., the higher the position. The pixel Px with height = 4 corresponds to the component body 91, and the pixel with height = 5 corresponds to the lever 93. The pixel Px in the area where the component 9 is not captured has a height = 20.

[0059] The region identification unit 841 identifies a background region AR2 based on the three-dimensional information HD as shown in FIG. 8A (step S7). In other words, the region identification unit 841 distinguishes between the inspection region AR1 and the background region AR2 in units of pixels Px. This distinction is made using a threshold height Thr set based on the component data acquired in step S1. In the case of the three-dimensional information HD of FIG. 8A, setting Thr=5 allows the lever 93 to be included in the background region AR2. In other words, a height region including the lever 93, which inhibits component recognition, can be defined as the background region AR2, and a region closer to the background region AR2 on the imaging optical axis AX can be defined as the inspection region AR1.

[0060] Next, the axis control unit 81 controls the X-axis servo motor 26 and the Y-axis servo motor 28 to move the head unit 4 above the multi-camera 11 (step S8). Note that if it is determined in step S4 that component C does not require background removal processing (NO in step S4), the above-mentioned steps S5 to S7 are skipped. When the head 4H holding component C passes by the multi-camera 11, the imaging control unit 82 causes the multi-camera 11 to perform an imaging operation and acquire a two-dimensional image of component C sucked by the suction nozzle 42 (step S9). Note that the imaging in step S9 is performed by the scan camera unit 6 depending on the component type.

[0061] 8(B) is a diagram showing a two-dimensional image IM1 of the underside of the terminal-equipped component 9 before the background removal correction process is performed. In other words, the two-dimensional image IM1 is the image of the terminal-equipped component 9 acquired by the imaging in step S9. As described above with reference to FIG. 5(B), in the two-dimensional image IM1, the high-brightness lever 93 is reflected in the background of the terminal 92A, and the shape of the terminal 92A cannot be accurately recognized.

[0062] The correction processing unit 842 performs correction processing to remove the background area AR2 from the two-dimensional image IM1 (step S10). In the three-dimensional information HD shown in FIG. 8(A), the coordinates of pixels Px at height h≧5 that form the background area AR2 are (X, Y)=(5, 19-21), (6, 19-21), (9, 19-21), (10, 19-21), and (11, 18-21). These pixels Px receive the light reflected by the whitish lever 93, and therefore appear as high-brightness pixels in the two-dimensional image IM for inspection. The correction processing unit 842 performs image processing to replace the brightness of these pixels Px with black.

[0063] 8(C) shows a two-dimensional image IM2 of the component 9 with terminals after background removal correction processing has been performed. In the two-dimensional image IM2, only the pixels Px at height h<5 have brightness, and the other areas, including the non-component area at height=20, are black. In other words, the lever 93 has been erased, and the image has been converted into a two-dimensional image IM2 in which the shape of the terminal 92A clearly appears. Note that if the component does not require background removal processing, step S10 is also skipped.

[0064] Thereafter, the determination unit 843 performs the required inspection of the component 9 with terminals based on the two-dimensional image IM2 (step S12). In step S12, inspection is performed based on predetermined criteria to determine whether the suction nozzle 42 is properly suctioning the component 9, whether the component 9 has been suctioned at all, and whether there are any defects in the component itself, such as loose or missing terminals. If the determination unit 843 determines that there is no abnormality (YES in step S12), the operation of mounting the component 9 held by the suction nozzle 42 onto the board P continues (step S13). Thereafter, the process returns to step S1, and the next mounting control is performed.

[0065] On the other hand, if the determination unit 843 determines that an abnormality has occurred (NO in step S12), the inspection processing unit 84 displays an error on a monitor provided in the surface mounter 1 or on a mobile terminal held by the worker, or issues an alarm (step S14). After that, the overall control unit 86 executes a predetermined retry operation for the component in which the error has occurred (step S15).

[0066] [Second embodiment] 9 is a plan view showing the configuration of a surface mounter 1A of the second embodiment. The surface mounter 1A differs from the surface mounter 1 of the first embodiment in that the TOF camera 12 of the surface mounter 1A also serves as a camera for acquiring two-dimensional images of the component C. In the surface mounter 1A, the TOF camera 12 is used as a camera for acquiring two-dimensional images of the component C to be inspected and three-dimensional information about the component C. That is, the inspection processing unit 84 of the second embodiment identifies a background region AR2 in the two-dimensional image of the component C acquired by the TOF camera 12 based on the three-dimensional information about the component C acquired by the TOF camera 12, and performs correction processing to remove the background region AR2.

[0067] In the second embodiment, the surface mounting machine 1A may also be equipped with a multi-camera 11, and the TOF camera 12 may acquire two-dimensional images and three-dimensional information about a predetermined component C. The configuration of the surface mounting machine 1A other than the TOF camera 12 is the same as that of the surface mounting machine 1 of the first embodiment, and therefore a description thereof will be omitted. In addition, the block diagram shown in FIG. 4 will be used in the following description of component mounting control.

[0068] 10 is a flowchart showing component mounting control by the surface mounter 1A of the second embodiment. When the process starts, the inspection processing unit 84 acquires component data for the component C to be picked up in the current turn from the storage unit 85 (step S21). The axis control unit 81 moves the head unit 4 to the component supply position of the component supply unit 3 (step S22), and causes the suction nozzle 42 to pick up the target component C (step S23).

[0069] Next, the axis control unit 81 moves the head unit 4 so that the head 4H holding the component C passes above the TOF camera 12 (step S24). At the timing when the head 4H reaches the TOF camera 12, the imaging control unit 82 causes the TOF camera 12 to perform an imaging operation (step S25). By the imaging operation of step S25, a two-dimensional IR image and three-dimensional information of the component C sucked by the suction nozzle 42 are acquired.

[0070] FIG. 11(A) is a diagram showing three-dimensional information HD acquired by TOF camera 12 when terminal-equipped component 9, as exemplified in FIG. 5(A), is the subject of imaging in step S25. The three-dimensional information HD here is the same as that shown in FIG. 8(A). FIG. 11(B) is a diagram showing two-dimensional IR image IM3 of component 9 acquired by TOF camera 12. Two-dimensional IR image IM3 is an image in which the brightness of each part of component 9 is expressed in grayscale from 0 to 256 gradations. In this two-dimensional IR image IM3, both terminal 92A and lever 93 are high-brightness parts, so the shape of terminal 92A cannot be clearly recognized.

[0071] Next, the inspection processing unit 84 determines whether the picked-up component C is a component that requires image processing to remove the background region AR2, based on the component data acquired in step S21 (step S26). If the inspection processing unit 84 determines that the component C requires background removal processing (YES in step S26), the region identification unit 841 identifies the background region AR2 based on the three-dimensional information HD as shown in Figure 11(A) (step S27). In the case of the three-dimensional information HD of Figure 11(A), a threshold height Thr is set to 5, and the inspection target region AR1 and the background region AR2 are clearly distinguished in units of pixels Px.

[0072] Thereafter, the correction processor 842 performs a correction process to remove the background region AR2 from the two-dimensional IR image IM3 (step S28). Specifically, the correction processor 842 performs image processing to replace the brightness of pixels Px at height h≧5, which constitute the background region AR2, with black. FIG. 11(C) is a diagram showing a two-dimensional IR image IM4 of the terminal-equipped component 9 after the background removal correction process has been performed. In the two-dimensional IR image IM4, the lever 93 has been removed, and the shape of the terminal 92A appears clearly. Note that if it is determined in step S26 that the component C does not require background removal processing (NO in step S26), the above-mentioned steps S27 to S28 are skipped.

[0073] Thereafter, the determination unit 843 performs a required inspection of the component with terminals 9 based on the two-dimensional IR image IM4 (step S29). If the determination unit 843 determines that there is no abnormality (YES in step S30), the mounting operation of the component 9 picked up by the suction nozzle 42 onto the board P continues (step S31). Thereafter, the process returns to step S21, and the next mounting control is performed. On the other hand, if the determination unit 843 determines that there is an abnormality (NO in step S30), the inspection processing unit 84 executes a predetermined error display or the like (step S32). Thereafter, the overall control unit 86 executes a predetermined retry operation for the component in which the error occurred (step S33).

[0074] According to the surface mounters 1 and 1A of the first and second embodiments described above, a background area AR2 located on the back side of the inspection target area AR1 on the imaging optical axis AX is identified based on the three-dimensional information HD of the component C held by the head 4H, and image processing is performed to remove the background area AR. Therefore, even if an object that reduces inspection accuracy appears in the background of the inspection target area AR1 in the two-dimensional inspection image IM1 or two-dimensional IR image IM3, the influence of the background can be eliminated. Therefore, reliable inspection of the inspection target area AR1 can be performed.

[0075] In the first embodiment, a multi-camera 11 for component recognition is used as an image acquisition unit that acquires two-dimensional images, and a TOF camera 12 is used as a three-dimensional measurement unit that acquires three-dimensional information. According to the first embodiment, the background area AR2 can be identified based on the three-dimensional information acquired by the TOF camera 12 for the two-dimensional images acquired by the multi-camera 11 that is normally equipped in the surface mounting machine 1. Therefore, simply by additionally installing a TOF camera 12 in an existing surface mounting machine 1, it is possible to provide the function of removing the background area AR2.

[0076] In the second embodiment, a TOF camera 12 is used as the image acquisition unit and the three-dimensional measurement unit. When a component is captured by the TOF camera 12, not only a two-dimensional image of the component is obtained, but also three-dimensional information of the component can be obtained based on the time from irradiation of the measurement light to reception of the reflected light. In other words, the image acquisition unit uses a function for acquiring a two-dimensional IR image IM3 using the imaging element 142 of the TOF camera 12. Furthermore, the three-dimensional measurement unit uses a function for acquiring three-dimensional information HD derived by the measurement processing unit 15 of the TOF camera 12. Therefore, the TOF camera 12 alone can perform the function of removing the background region AR2. [Explanation of symbols]

[0077] 1. Surface mounter (component mounting device) 11 Multi-camera (image acquisition unit) 12 TOF camera (3D measurement unit) 4H head 62 Scan camera (image acquisition unit) 8. Control Unit 84 Inspection processing section 841 Area identification part 842 Correction processing unit 843 Judgment Department (Inspection Department) 85 Storage section 9 Parts with terminals 91 Part body 92 Lead (Terminal) 92A, 92B terminals 93 Lever AX Imaging optical axis AR1 Inspection area AR2 background area C parts L1, L2 measurement light, reflected light HD 3D information IM1~IM4 2D images P board

Claims

1. a head that holds the components and mounts them on the board; an image acquisition unit that captures an image of the component held by the head and acquires a two-dimensional image of the component; a three-dimensional measurement unit that irradiates a component held by the head with measurement light and acquires three-dimensional information about the component based on the time it takes for reflected light from the component to be obtained; a correction processing unit that identifies a background area located on the imaging optical axis of the image acquisition unit behind a predetermined inspection target area for the component based on the three-dimensional information of the component, and performs image processing to remove the background area from the two-dimensional image of the component; an inspection unit that performs a required inspection of the component based on the two-dimensional image of the component that has been subjected to the image processing; A component mounting device comprising:

2. 2. The component mounting apparatus according to claim 1, the component is an electronic component having a terminal, The component mounting apparatus, wherein the inspection target area is an area in which the terminals of the component are present.

3. 3. The component mounting apparatus according to claim 2, The correction processing unit removes the inner side of an area located around the terminal in a direction in which the imaging optical axis extends.

4. 2. The component mounting apparatus according to claim 1, a storage unit for storing part data relating to the shape of the part; The component mounting apparatus, wherein the correction processing unit divides the inspection target area and the background area based on the component data.

5. The component mounting device according to any one of claims 1 to 4, The correction processing unit performs image processing to replace pixels in a portion of the two-dimensional image that is identified as the background region with black.

6. The component mounting device according to any one of claims 1 to 4, a TOF camera capable of acquiring a two-dimensional image including height information; the image acquisition unit uses a two-dimensional image acquisition function of the TOF camera, The component mounting device, wherein the three-dimensional measurement unit uses a function of acquiring height information from the TOF camera.

7. The component mounting device according to any one of claims 1 to 4, Further provided with a TOF camera capable of acquiring three-dimensional information of the part; the image acquisition unit is a component recognition camera that captures an image of a component from below to acquire a two-dimensional image, The correction processing unit performs image processing on the two-dimensional image acquired by the component recognition camera based on the three-dimensional information acquired by the TOF camera.

Images