JP2019036015A - Surface mounting machine - Google Patents

Abstract

To correctly determine presence or absence of a component even when color of the component is similar to the color of a housing recess.SOLUTION: A surface mounting machine 1 holds a component E supplied by a component tape 18 which has a housing recess 18B housing the component E and the component E housed in the housing recess 18B, and mounts the component E on a base board P. The surface mounting machine 1 comprises an imaging unit which captures the housing recess 18B and generates an image, and a control unit 30. The control unit 30 executes: edge image generation processing which extracts an edge from the image and generates an edge image; identifying processing for identifying an edge pixel number which is the number of pixels corresponding to the edge of the edge image; and determination processing which determines the presence of the component when the edge pixel number is equal to or more than a threshold value, and determines the absence of the component when the edge pixel number is less than the threshold value.SELECTED DRAWING: Figure 7

Description

  The technology disclosed in this specification relates to a surface mounter that holds a component supplied by a component tape and mounts the component on a substrate.

Conventionally, in a surface mounter that holds a component supplied by a component tape having an accommodating recess for accommodating the component and a component accommodated in the accommodating recess, and determines whether there is a component in the accommodating recess. Is known (see, for example, Patent Document 1).
Specifically, in the component inspection method described in Patent Document 1, a component pocket (corresponding to an accommodation recess) that is a target for determining the presence or absence of a component and a previous component pocket (empty component pocket) are imaged. To do. In the component inspection method, a suction position window is set in the target component pocket on the captured image, a front suction position window is set in the previous component pocket, and the average luminance value of the suction position window is set. Is near the average of the luminance values of the front suction position window, it is determined that there is no part.

JP 2014-72409 A

However, according to the component inspection method described in Patent Document 1, if the color of the component is close to the color of the component pocket, there is a possibility that it is erroneously determined that there is no component even though there is a component.
The present specification discloses a technique that can more accurately determine the presence or absence of a component even when the color of the component is close to the color of the housing recess.

  The surface mounter disclosed in this specification is a surface mounter that holds the component supplied by a component tape having a housing recess for housing the component and a component housed in the housing recess and mounts the component on a substrate. An imaging unit configured to capture an image of the housing recess and generate an image; and a control unit, wherein the control unit extracts an edge from the image and generates an edge image; Specific processing for specifying the number of edge pixels, which is the number of pixels corresponding to the edge of the edge image, and determining that there is a component when the number of edge pixels is greater than or equal to a threshold, and determining that there is no component when the number is less than the threshold Determination processing to be executed.

In general, since the electrode of the component is a metal, even if the color of the surface of the electrode is uniform, the surface of the electrode becomes a spotted pattern with light and shade mixed in an image obtained by imaging the component. For this reason, when an edge is extracted from an image obtained by imaging a part, the shading boundary on the surface of the electrode is extracted as an edge. Therefore, when there are parts in the housing recess, the number of pixels corresponding to the edges increases.
On the other hand, in general, in the image obtained by imaging the inner surface of the receiving recess of the component tape, the shading of the inner surface of the component is substantially uniform. For this reason, it is hard to extract an edge compared with the image which imaged components. Therefore, when there is no part, the number of pixels corresponding to the edge is reduced by imaging the inner surface of the housing recess.
Therefore, if the presence / absence of a component is determined based on the number of edge pixels, which is the number of pixels corresponding to the edge, the presence / absence of the component is more correctly determined even when the color of the component is close to the color of the inner surface of the housing recess. be able to.

  The control unit may extract an edge by applying a horizontal edge extraction filter and a vertical edge extraction filter to the image in the edge image generation process.

  According to the above surface mounter, since the edge extraction filter in the horizontal direction and the edge extraction filter in the vertical direction are applied to the image, the edge can be extracted with high accuracy. As a result, the presence / absence of a component can be determined more correctly.

  In the edge image generation process, the control unit generates an intermediate edge image by extracting an edge from the image and binarizes the intermediate edge image to generate a binary image. By executing a binary image generation process, an edge expansion process that expands an edge of the binary image, and an edge contraction process that contracts an edge of the binary image whose edges are expanded by the edge expansion process The edge image may be generated.

  According to the above surface mounter, since the intermediate edge image is binarized, it is possible to separate the pixels corresponding to the edges and the pixels not corresponding to the edges. This facilitates specifying the number of edge pixels. However, when the intermediate edge image is binarized, for example, only one pixel may be isolated as a pixel corresponding to an edge. In that case, since the surrounding pixels are likely to be pixels corresponding to the edge, it is desirable that the surrounding pixels be included in the pixels corresponding to the edge. When edge expansion processing and edge contraction processing are performed on a binary image, for example, when only one pixel is isolated as a pixel corresponding to an edge, pixels around that pixel can also be set as pixels corresponding to an edge. . For this reason, the number of edge pixels can be specified more appropriately.

  In addition, the control unit performs a counting process for counting the number of times the holding of the component housed in the housing recess is failed, and if the determination process determines that there is no component in the counting process, the component Even if it cannot be held, it may be excluded from the number of failures.

  According to the above surface mounter, since the presence / absence of a component can be more correctly determined, a decrease in the suction rate can be more reliably suppressed when the component is not included in the housing recess and excluded from the suction miscount.

  Further, the imaging unit may image the housing recess next to the housing recess located at a component supply position that is a position where the component is supplied from the component tape to the surface mounter.

  When the mounting head is lowered and the housing recess is imaged in parallel, if there are no parts in the housing recess, the mounting head has been lowered, resulting in a loss of tact time. According to the above surface mounter, the presence or absence of a component is determined by imaging the accommodation recess next to the accommodation recess positioned at the component supply position. For this reason, when there is no part in the next receiving recess, it is known that there is no part when the parts tape is fed and the next receiving recess is located at the component supply position. It's okay. Thereby, loss of tact time can be reduced.

Top view of the surface mounter according to the first embodiment Side view of head unit and tape feeder Cross section of component tape Block diagram showing the electrical configuration of the surface mounter Flow chart of adsorption control processing Schematic diagram showing an example of a component Schematic diagram for explaining conventional determination of presence / absence of parts and determination of presence / absence of parts according to the first embodiment Flow chart of parts presence / absence judgment processing Edge image generation processing flowchart (A) is a schematic diagram of a horizontal sobel filter, (b) is a schematic diagram of a vertical sobel filter. Schematic diagram showing an example of applying a sobel filter Schematic diagram showing a first example of white expansion processing and white contraction processing Schematic diagram showing a second example of white expansion processing and white contraction processing FIG. 6 is a schematic diagram illustrating imaging of an accommodation recess according to the second embodiment.

<Embodiment 1>
A first embodiment will be described with reference to FIGS. In the following description, the left-right direction shown in FIG. 1 is called the X-axis direction, the front-rear direction is called the Y-axis direction, and the up-down direction shown in FIG. In the following description, the right side shown in FIG. 1 is called the upstream side, and the left side is called the downstream side. In the following description, the same constituent members may be omitted from the drawings except for some parts.

(1) Overall Configuration of Surface Mounter As shown in FIG. 1, the surface mounter 1 includes a base 10, a transport conveyor 11, four component supply devices 12, a head unit 13, a head transport unit 14, and two component imaging cameras. 15, the board imaging camera 16 (an example of an imaging unit), the control unit 30 and the operation unit 31 shown in FIG.

  The base 10 has a rectangular shape in plan view and a flat upper surface. In FIG. 1, a rectangular frame A indicated by a two-dot chain line indicates a work position when the component E is mounted on a substrate P such as a printed circuit board.

  The conveyor 11 carries the board P from the upstream side in the X-axis direction to the work position A, and carries the board P on which the component E is mounted at the work position A to the downstream side. The conveyor 11 includes a pair of conveyor belts 11A and 11B that circulate and drive in the X-axis direction, a conveyor drive motor 43 (see FIG. 4) that drives the conveyor belts 11A and 11B, and the like. The rear conveyor belt 11A is movable in the front-rear direction, and the distance between the two conveyor belts 11A and 11B can be adjusted according to the width of the substrate P.

  The component supply devices 12 are arranged at four places, two places in the X-axis direction on both sides in the Y-axis direction of the conveyor 11. A plurality of feeders 17 are attached to these component supply devices 12 so as to be arranged side by side in the X-axis direction. Each feeder 17 is a so-called tape feeder, and a reel (not shown) around which a component tape 18 (see FIG. 3) containing a plurality of components E is wound, and an electric tape that pulls out the component tape 18 from the reel. A delivery device 19 (see FIG. 2) and the like are provided, and components E are supplied one by one from a component supply position 25 (see FIGS. 2 and 3) provided at the end on the conveyor 11 side.

The head unit 13 supports a plurality (eight in this case) of mounting heads 20 so as to be movable up and down and rotatable around an axis. The head unit 13 according to this embodiment is a so-called rotary type, and a plurality of mounting heads 20 are arranged on the circumference at equal intervals. The configuration of the head unit 13 will be described later.
Although the rotary type head unit 13 is described here as an example, the head unit 13 may be a so-called inline type in which a plurality of mounting heads 20 are arranged in a line in the X-axis direction, for example.

  The head transport unit 14 transports the head unit 13 in the X axis direction and the Y axis direction within a predetermined movable range. The head transport unit 14 includes a beam 21 that supports the head unit 13 so as to be reciprocally movable in the X-axis direction, a pair of Y-axis guide rails 22 that support the beam 21 so as to be reciprocally movable in the Y-axis direction, and the head unit 13. Are provided with an X-axis servo motor 38 that reciprocally moves the beam 21 in the X-axis direction, a Y-axis servo motor 39 that reciprocates the beam 21 in the Y-axis direction, and the like.

  The two component imaging cameras 15 image components E sucked by the mounting head 20 from below. The front component imaging camera 15 is disposed between two component supply devices 12 arranged in the X-axis direction on the front side of the conveyor. The rear component imaging camera 15 is disposed between two component supply devices 12 arranged in the X-axis direction on the rear side of the transport conveyor.

  The substrate imaging camera 16 is for imaging a fiducial mark attached to the substrate P, and is provided in the head unit 13. In the present embodiment, the board imaging camera 16 is also used for imaging a housing recess 18B (see FIG. 3) of a component tape 18 described later. The board imaging camera 16 will be described later.

(2) Head Unit and Board Imaging Camera Next, the head unit 13 and the board imaging camera 16 will be described in detail with reference to FIG.
The head unit 13 has a main body 13A and a rotary head 13B supported by the main body 13A so as to be rotatable about a vertical line. A plurality of mounting heads 20 are arranged at equal intervals on the circumference of the rotary head 13B. Each mounting head 20 has an elongated cylindrical head shaft 23 and a suction nozzle 24 detachably attached to the lower end of the head shaft 23. A negative pressure and a positive pressure are supplied to the suction nozzle 24 from an air supply device (not shown) via the head shaft 23. The suction nozzle 24 sucks (e.g., holds) the part E when a negative pressure is supplied, and releases the part E when a positive pressure is supplied.

  The main body 13A includes a head rotation motor 40 (see FIG. 4) for rotating the rotary head 13B, and a Z-axis servo motor 41 (see FIG. 4) for lowering the mounting head 20 moved to the predetermined head lowering position on the circumference. ), And an R-axis servo motor 42 (see FIG. 4) for rotating the mounting heads 20 around the axis at once. The control unit 30 described later rotates the rotary head 13B to move the mounting head 20 to be lowered to the head lowering position, and lowers the mounting head 20 that has moved to the head lowering position by the Z-axis servo motor 41.

  The board imaging camera 16 is provided at the lower end of the main body 13 </ b> A of the head unit 13. The board imaging camera 16 includes an imaging sensor, a light source such as an LED that irradiates light to the subject, an optical system that forms an image on the light receiving surface of the imaging sensor, and the like. It is arranged in such a posture that the axis is inclined.

(3) Component Tape As shown in FIG. 3, the component tape 18 includes a carrier tape 18A in which a plurality of receiving recesses 18B are provided at equal intervals in the longitudinal direction, a component E stored in each receiving recess 18B, and The release tape 18C is attached to the upper surface of the carrier tape 18A. The component tape 18 is provided with feed holes (not shown) into which sprocket teeth provided in the feeder 17 are inserted at equal intervals along the longitudinal direction, and the component tape 18 is fed by rotating the sprocket.

  In FIG. 3, the position 25 is the above-described component supply position of the feeder 17. The feeder 17 is provided with a peeling device (not shown) that peels off the peeling tape 18C before the component supply position 25. The peeling tape 18C is peeled off by the peeling device before each component recess 18B before the component supply position 25. Then, when the housing recess 18B reaches the component supply position 25, the feeding of the component tape 18 is stopped. In this state, the mounting head 20 descends to attract the component E, and the board imaging camera 16 causes the housing recess 18B to move. Imaged.

(4) Electrical Configuration of Surface Mounter As shown in FIG. 4, the surface mounter 1 includes a control unit 30 and an operation unit 31. The control unit 30 includes an arithmetic processing unit 32, a motor control unit 33, a storage unit 34, an image processing unit 35, an external input / output unit 36, a feeder communication unit 37, and the like.

  The arithmetic processing unit 32 includes a CPU, a ROM, a RAM, and the like, and controls each unit of the surface mounter 1 by executing a control program stored in the ROM. The arithmetic processing unit 32 may include an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or the like instead of the CPU or in addition to the CPU.

The motor control unit 33 controls the X-axis servo motor 38, the Y-axis servo motor 39, the head rotation motor 40, the Z-axis servo motor 41, the R-axis servo motor 42, the conveyor drive motor 43, and the like under the control of the arithmetic processing unit 32. Rotate the motor.
Various data are stored in the storage unit 34. Various types of data include information on the number and type of boards P to be produced, information on the mounting coordinates and mounting angles of the parts E, information on the mounting order of the parts E, and the like.

The image processing unit 35 is configured to receive image signals output from the component imaging camera 15 and the board imaging camera 16, and generates a digital image based on the output image signals.
The external input / output unit 36 is a so-called interface, and is configured to receive detection signals output from various sensors 44 provided in the main body of the surface mounter 1. The external input / output unit 36 is configured to perform operation control on various actuators 45 based on a control signal output from the arithmetic processing unit 32.

The feeder communication unit 37 is connected to the feeder 17 and controls the feeder 17 in an integrated manner.
The operation unit 31 includes a display device such as a liquid crystal display and input devices such as a touch panel, a keyboard, and a mouse. The operator can perform various settings by operating the operation unit 31.

(5) Processing executed by control unit Next, processing executed by the control unit 30 will be described. Here, suction control processing, component presence / absence determination processing, and suction miscount processing (an example of count processing) will be described as processing executed by the control unit 30.

(5-1) Adsorption Control Processing With reference to FIG. 5, the adsorption control processing will be described. The suction control process is a process of sucking the component E housed in the housing recess 18 </ b> B of the component tape 18 by the mounting head 20. This process is started when the housing recess 18B reaches the component supply position 25 and the feeding of the component tape 18 is stopped.

In S101, the control unit 30 lowers the mounting head 20 to attract the component E. However, the suction may fail when the component E accommodated in the accommodating recess 18B is inclined or the position of the component E is shifted. Further, there is a case where the component E is not accommodated in the accommodation recess 18B for some reason, and the component E may not be adsorbed.
In S102, the control unit 30 images the accommodation recess 18B by the substrate imaging camera 16 in parallel with the lowering of the mounting head 20 in S101.

In S <b> 103, the control unit 30 raises the mounting head 20.
In S104, the control unit 30 executes a component presence / absence determination process in parallel with the rise of the mounting head 20 in S103. As will be described in detail later, in the component presence / absence determination process, it is determined based on the image captured in S102 whether or not there is the component E in the housing recess 18B.
In S105, when the control unit 30 determines that there is a part in the part presence / absence determination process (S105: Yes), the process ends. When it is determined that there is no part (S105: No), the process proceeds to S106.
In S106, the control unit 30 excludes the adsorption miscount.

  Here, the case where imaging of the housing recess 18B is performed in parallel with the lowering of the mounting head 20 has been described as an example, but imaging of the housing recess 18B may be performed before the mounting head 20 is lowered, It may be performed after the mounting head 20 is lowered. Although the case where the component presence / absence determination process is executed in parallel with the rise of the mounting head 20 has been described here as an example, the component presence / absence determination process may be executed after the mounting head 20 is raised.

(5-2) Component Existence Determination Process First, the outline of the component presence / absence determination process executed in S104 will be described with reference to FIGS.
First, an example of the component E will be described with reference to FIG. The part E shown in FIG. 6 has a horizontally long cubic shape and is molded with resin. The mold color is, for example, black (or a color close to black) or white (or a color close to white). Metal electrodes 51 are provided on both sides of the component body 50 in the longitudinal direction. The upper surface of each electrode 51 is flat and the color is almost uniform.

Next, with reference to FIG. 7, an example of an image obtained by capturing the accommodation recess 18 </ b> B in which the component E is accommodated and the accommodation recess 18 </ b> B in which the component E is not accommodated will be described.
Example 1 is an image obtained by capturing the housing recess 18B in which the component E having a black mold color is housed. Examples 2 to 3 are images obtained by capturing the housing recess 18B in which the component E having a white mold color is housed. The part E of Example 3 is the same as the part E of Example 2, but in Example 3, imaging is performed with the luminance of the light source being higher (that is, brighter) than in Example 2. Example 4 is an image obtained by capturing the housing recess 18B in which the part E is not housed. Here, in Examples 1 to 4, the color of the carrier tape 18A is white including the inner surface of the housing recess 18B.

  In the conventional determination of the presence / absence of a component, a binary image is generated by binarizing an image obtained by capturing the accommodating recess 18B, and the component is determined depending on whether the number of pixels representing black in the generated binary image is equal to or greater than a threshold value. The presence or absence of E was judged.

  For example, in Example 1, since the mold color of the part E is black, the number of black pixels is 1132. For this reason, it is determined that there is a component both when the threshold value is 100 and when the threshold value is 33. In Example 2, since the mold color is white, binarization results in almost white pixels, and the number of black pixels is 79. For this reason, when the threshold value is 33, it is determined that there is a component, but when the threshold value is 100, it is erroneously determined that there is no component despite the presence of the component E.

  In Example 3, since the luminance of the light source is high, the number of black pixels is 16, which is further smaller than in Example 2. For this reason, whether the threshold value is 100 or 33, it is erroneously determined that there is no component despite the presence of the component E. In Example 4, the number of black pixels is 69 because the pixels representing the shadowed portion of the side wall of the accommodating recess 18B are counted as black pixels. For this reason, when the threshold is 100, it is determined that there is no component, but when the threshold is 33, it is erroneously determined that there is a component even though there is no component E.

Thus, in the conventional determination of the presence / absence of a component, if the mold color of the component E is significantly different from the color (white) of the inner surface of the housing recess 18B (that is, the mold color is black), the presence / absence of the component E is correctly determined. can do. However, when the mold color of the part E is close to the color of the inner surface of the accommodating recess 18B (that is, when the mold color is white), when the threshold value is large (that is, when 100), the cases of Example 2 and Example 3 are erroneously determined. If the threshold is small (that is, 33), it is erroneously determined in the case of Example 3 and Example 4.
That is, in the conventional determination of the presence / absence of a component, if the mold color of the component E is close to the color of the inner surface of the housing recess 18B, it is not possible to eliminate erroneous determinations regardless of whether the threshold value is increased or decreased. The nature was not necessarily high.

  In contrast, in the component presence / absence determination processing according to the present embodiment, the control unit 30 generates an edge image from an image obtained by capturing the housing recess 18B of the component tape 18, and the number of pixels corresponding to the edge of the generated edge image. The presence / absence of the part E is determined based on a certain number of edge pixels. This will be specifically described below.

  The edge image shown in FIG. 7 is generated by extracting edges from the images shown in Examples 1 to 4. In the edge image, a white area represents an edge. In the following description, a pixel (white pixel) constituting a white region is referred to as a pixel corresponding to an edge.

  Here, although details will be described later, in the present embodiment, an edge is extracted from an image obtained by capturing the accommodation recess 18B to generate an intermediate edge image, and a binary image obtained by binarizing the generated intermediate edge image is described later as a white image. An edge image is generated by performing an expansion process (an example of an edge expansion process) and a white contraction process (an example of an edge contraction process) in this order. When the white expansion process and the white contraction process are executed, if there is a pixel (or pixel group) isolated from the surroundings among the pixels corresponding to the edge, the pixels around the pixel also become pixels corresponding to the edge. . That is, the edge expands. The edge image shown in FIG. 7 is an image after white expansion processing and white contraction processing are performed.

  As described above, the upper surface of the electrode 51 is flat and the color is almost uniform, but the light reflectance of the upper surface of the electrode 51 is high, the direction of reflection is not necessarily uniform, and the resolution of the substrate imaging camera 16 is high. For this reason, as shown in Examples 1 to 3, the upper surface of the electrode 51 has a mixed pattern of shades on the image obtained by imaging the housing recess 18B. For this reason, when the intermediate edge image is generated, the density difference is extracted as an edge, and the edges are concentrated in a region corresponding to the upper surface of the electrode 51. Since the edge is expanded by the white expansion process and the white contraction process, in the edge image, there is almost no gap between adjacent edges in the region corresponding to the upper surface of the electrode 51.

For this reason, the edge is usually a line, but in the edge images of Examples 1 to 3, the edge of the region corresponding to the upper surface of the electrode 51 is a surface, and most of the pixels corresponding to the upper surface of the electrode 51 are edges. Is a pixel corresponding to (white pixel).
On the other hand, in the region corresponding to the inner surface of the component main body 50 and the housing recess 18B, the pixel density is almost uniform, so that it is difficult to extract the edge. For this reason, in the edge image, many of the pixels corresponding to the inner surfaces of the component main body 50 and the accommodating recess 18B are pixels (black pixels) that do not correspond to the edge.

  That is, when there is the part E in the housing recess 18B, many of the pixels corresponding to the upper surface of the electrode 51 correspond to edges, so whether or not the mold color of the part E is close to the color of the inner surface of the housing recess 18B. The number of pixels corresponding to the edge increases. Specifically, in Examples 1 to 3 which are examples in the case where the component E is present, the number of pixels corresponding to the edges is 1616, 1344 and 1185. On the other hand, when there is no part E, the number of pixels corresponding to the edge is reduced. Specifically, in Example 4, which is an example when there is no component E, the number of pixels corresponding to the edge is 1055.

  Therefore, if a threshold value is set between 1185 and 1055, the presence / absence of the component E can be correctly determined even when the color of the component E is close to the color of the inner surface of the housing recess 18B. Specifically, since 1100 is set as the threshold value in the example shown in FIG. 7, it can be correctly determined that there are parts in Examples 1 to 3, and it can be correctly determined that there are no parts in Example 4. it can.

Next, the flow of the part presence / absence determination process will be described with reference to FIG.
In S201, the control unit 30 executes an edge image generation process. As will be described in detail later, in the edge image generation process, edges are extracted from the image generated by imaging the housing recess 18B in S102, and an edge image is generated.
In S202, the control unit 30 counts the number of pixels having a density of 255 (that is, pixels corresponding to edges) from the edge image generated in S201. Thereby, the number of edge pixels is specified (an example of specifying processing).

In S203, the control unit 30 determines whether or not the number of edge pixels specified in S202 is equal to or greater than a threshold (1100 in the example illustrated in FIG. 7). If the number is equal to or greater than the threshold (S203: Yes), the process proceeds to S204. If less (S203: No), the process proceeds to S205.
In S204, the control unit 30 determines that there is a part.
In S205, the control unit 30 determines that there are no parts. The above-described S203 to S205 are an example of determination processing.

Next, the edge image generation process executed in S201 will be described with reference to FIG.
In S301, the control unit 30 generates an intermediate edge image by applying an edge extraction filter to the image generated by imaging the housing recess 18B in S102 (an example of intermediate edge image generation processing). This will be specifically described below.

  First, an edge extraction filter used in this embodiment will be described with reference to FIG. The edge extraction filter may be referred to as an edge enhancement filter. In the present embodiment, a sobel filter is used as the edge extraction filter. In general, the sobel filter is a filter that is light in processing and has high edge extraction capability. 10A and 10B, the sobel filter includes a horizontal sobel filter 55 (an example of a horizontal edge extraction filter) and a vertical sobel filter 56 (an example of a vertical edge extraction filter). When the gradation values of the pixels adjacent to the left and right in the horizontal direction are the same, they are canceled out and become zero, and when the gradation values of the pixels adjacent in the vertical direction are the same, they are canceled and become zero. Also, 1, -1, 2, and -2 in FIGS. 10A and 10B are examples of weighting.

  Next, an example in which a sobel filter is applied will be described with reference to FIG. Here, the pixel density is expressed by 256 gradations from 0 (black) to 255 (white). In addition, here, it is assumed that the density of a pixel to which no density is added in each image shown in FIG.

An image 60 is an image before the sobel filter is applied. The image 61 is an image generated by applying the horizontal direction sobel filter 55 to the image 60, and the image 62 is an image generated by applying the vertical direction sobel filter 56 to the image 60. An image 63 is an intermediate edge image generated from the images 61 and 62. Specifically, in the sobel filter, the square root of the square sum of the density of the pixel of the image 61 and the density of the pixel at the same coordinate of the image 62 is set as the density of the pixel of the coordinate of the intermediate edge image 63. However, in the sobel filter, the square root of the sum of squares may be larger than 255. If the square root of the sum of squares is greater than 255, it is replaced with 255.
In the intermediate edge image 63, a rectangular frame-shaped region constituted by pixels with a density represents an extracted edge. That is, in the example shown in FIG. 11, a rectangular frame-like edge is extracted by applying a sobel filter.

  The intermediate edge image 63 may be an edge image, and it may be determined that there is a component as long as the number of pixels constituting the rectangular frame portion (that is, the number of edge pixels) is equal to or greater than a threshold value. For example, in the intermediate edge image 63 shown in FIG. 11, the total number of pixels is 91 and the number of edge pixels is 64 of them. In this case, if the preset threshold value is 60, the number of edge pixels is equal to or greater than the threshold value, and therefore it is determined that there is a component in S203 of FIG.

  In S302, the control unit 30 binarizes the intermediate edge image to generate a binary image (an example of a binary image generation process). Specifically, for example, the control unit 30 sets 100 as a threshold, pixels having a density of 100 or more are pixels corresponding to edges (white pixels), sets the density to 255, and pixels having a density of less than 100 do not correspond to edges. The density is set to 0 assuming that the pixel is a black pixel. As a result, a binary image having a pixel density of 0/255 is generated. Note that the threshold value is not limited to 100, and can be determined as appropriate. Further, the binary image may represent the pixel density by 0/1.

  In S303, the control unit 30 performs a white expansion process for expanding the edges of the binary image generated in S302 and a white contraction process for contracting the edges of the binary image whose edges are expanded by the white expansion process in this order. . This will be specifically described below.

  When the edge image is binarized, for example, only one pixel may be isolated as a pixel corresponding to the edge. In that case, the surrounding pixels are likely to be pixels corresponding to the edge. However, since the density of the surrounding pixels is small, the surrounding pixels may be regarded as pixels that do not correspond to the edge during binarization. In order to specify the number of edge pixels with high accuracy, it is desirable that such surrounding pixels be pixels corresponding to edges. The white expansion process and the white contraction process are processes in which such surrounding pixels are pixels corresponding to edges. Hereinafter, the white expansion process and the white contraction process will be described more specifically with reference to two examples.

First, a first example will be described with reference to FIG. The first example is an example in which there is no pixel isolated from the surroundings among the pixels corresponding to the edge. In FIG. 12, a binary image 65 is a binary image generated by the above-described binarization.
In the white expansion process, the maximum value in a 3 × 3 pixel range (hereinafter referred to as “neighboring region”) centered on the target pixel is used as the density of the target pixel. For example, assuming that the pixel 68 is the target pixel, the maximum value of the neighboring region is 255 of the pixel 68A, so that the density of the pixel 68 is 255 as shown in the binary image 66. When the white image expansion processing is performed on all the pixels of the binary image 65 except for the pixels at the outer edge in order as the target pixels, pixels around the pixels corresponding to the edges are also pixels corresponding to the edges as shown in the binary image 67. Become. That is, the edge expands.

In the white shrinking process, the minimum value in the vicinity region of the target pixel is set as the density of the target pixel. In the first example, when the white image shrinkage processing is performed on all the pixels of the binary image 67 except the outer edge portion in order as the target pixels, the original binary image 65 is restored. That is, when there is no pixel isolated from the surroundings among the pixels corresponding to the edges, all the expanded edges contract, and as a result, the edges do not expand.
In this example, if the preset threshold value is 60, the number of pixels in the rectangular frame portion of the binary image (that is, the binary image 65) after the white contraction process is 68. Because it is equal to or greater than the threshold, it is determined that there is a part.

  Note that the neighborhood region is not limited to the range of 3 × 3 pixels, and can be determined as appropriate. For example, the neighborhood region may be a range of 5 × 5 pixels.

Next, a second example will be described with reference to FIG. The second example is an example in which only one pixel is isolated from the surroundings among the pixels corresponding to the edge. Specifically, in the binary image 70 shown in the second example, a pixel 73 corresponding to an edge is isolated near the center.
As shown in the binary image 71, when the white image expansion process is performed on the binary image 70, the pixels around the pixel 73 are also 255. As shown in the binary image 72, when the white image 71 is subjected to the white contraction process, the density of the left and right pixels of the pixel 73 does not return to 0 and remains 255. Therefore, in the second example, the binary image 72 is not the same as the original binary image 70, and the left and right pixels of the isolated pixel 73 remain as pixels corresponding to the edge. That is, when there is a pixel that is isolated from the surroundings among the pixels corresponding to the edge, a part of the expanded edge does not contract, and as a result, the edge expands compared to the original binary image. .
In this example as well, assuming that the preset threshold value is 60, the number of pixels of the rectangular frame-shaped portion and the expanded portion of the binary image 75 after the white shrinkage processing is 71, and the threshold value Therefore, it is determined that there are parts.

  In the second example, the case where only one pixel is isolated has been described as an example. However, when a pixel group composed of two or more continuous pixels is isolated like an isolated island, the edge expands as a result.

(5-3) Adsorption Miscount Process The adsorption miscount process is a process of counting as an adsorption error when the adsorption of the component E has failed (in other words, an adsorption error) in S101 described above, and calculating the adsorption rate from the counted number. It is. The adsorption rate is calculated by, for example, the following formula 1.

  Adsorption rate [%] = {(number of adsorption attempts−number of adsorption failures) / number of adsorption attempts} × 100 Formula 1

  However, as described above, the component E may not be accommodated in the accommodating recess 18 </ b> B of the component tape 18. In that case, the component E cannot be picked up, but it does not mean that a picking mistake has occurred, and in that case, if it is counted as a picking mistake, the picking rate will decrease. For this reason, when the controller 30 excludes the suction error count in S106 described above, the controller 30 does not count the suction error even if the component E cannot be sucked.

(6) Effects of Embodiment According to the surface mounter 1 according to the first embodiment described above, since the presence / absence of the component E is determined based on the number of edge pixels, which is the number of pixels corresponding to the edge, the mold of the component E Even if the color is close to the color of the inner surface of the housing recess 18B, the presence or absence of the part E can be determined more correctly.

  Further, according to the surface mounter 1, a sobel filter is used as the edge extraction filter. The sobel filter is a filter that extracts an edge by applying a horizontal edge extraction filter and a vertical edge extraction filter to an image. Since the sobel filter has a high edge extraction capability, the edge can be extracted with high accuracy. Thereby, the presence or absence of the part E can be judged more correctly.

  Further, according to the surface mounter 1, since the intermediate edge image generated by extracting the edge from the image obtained by capturing the accommodation recess 18B is binarized, the pixel corresponding to the edge and the pixel not corresponding to the edge can be separated. it can. This facilitates specifying the number of edge pixels. However, when the intermediate edge image is binarized, for example, only one pixel may be isolated as a pixel corresponding to an edge. In that case, since the surrounding pixels are likely to be pixels corresponding to the edge, it is desirable that the surrounding pixels be included in the pixels corresponding to the edge. When edge expansion processing and edge contraction processing are performed on a binary image, for example, when only one pixel is isolated as a pixel corresponding to an edge, pixels around that pixel can also be set as pixels corresponding to an edge. . For this reason, the number of edge pixels can be specified more appropriately.

  Moreover, according to the surface mounting machine 1, when the component E is not in the accommodation recessed part 18B, when excluding from adsorption | suction miscount, the fall of an adsorption | suction rate can be suppressed more reliably. Specifically, if the presence / absence of the component E cannot be correctly determined, even if the suction of the component E fails due to the absence of the component E, it is erroneously determined that the component E is present and is counted as a suction error. there is a possibility. According to the surface mounter 1, since the presence / absence of the component E can be determined more correctly, the possibility that the component E is erroneously determined to be counted as a suction error can be reduced. For this reason, the fall of an adsorption rate can be suppressed more reliably.

<Embodiment 2>
Next, Embodiment 2 of the present invention will be described with reference to FIG.
In the above-described first embodiment, the housing recess 18B located at the component supply position 25, which is the position where the component E is supplied from the component tape 18 to the surface mounter 1, is imaged by the board imaging camera 16 to determine the presence or absence of the component E. The case of making a determination has been described as an example. On the other hand, as shown in FIG. 14, in the second embodiment, the presence or absence of the component E is determined by imaging the storage recess 18 </ b> B next to the storage recess 18 </ b> B located at the component supply position 25.

  Specifically, in the second embodiment, as compared with the first embodiment, a peeling device (not shown) for peeling the peeling tape 18C is arranged on the upstream side in the feeding direction of the component tape 18 and is located at the component supply position 25. The receiving recess 18B next to the receiving recess 18B is also in a state where the peeling tape 18C is peeled off.

  When the control unit 30 according to the second embodiment lowers the mounting head 20 in order to suck the component E housed in the housing recess 18 </ b> B located at the component supply position 25, the control unit 30 is parallel to the lowering of the mounting head 20. Then, the next housing recess 18B is imaged by the board imaging camera 16, and the presence or absence of the component E in the next housing recess 18B is determined from the captured image. The next imaging of the accommodating recess 18B may be performed before the mounting head 20 is lowered, or may be performed after the mounting head 20 is lowered.

  And the control part 30 judges the presence or absence of the component E of the next accommodation recessed part 18B from the image which imaged the next accommodation recessed part 18B. Then, when there is no component E in the next receiving recess 18B, the control unit 30 has already found that there is no component E when the component tape 18 is fed and the next receiving recess 18B is positioned at the component supply position 25. Therefore, the mounting head 20 is not lowered. Thereby, loss of tact time can be reduced.

<Other embodiments>
The technology disclosed in the present specification is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope disclosed by the present specification.

  (1) In the above embodiment, the sobel filter is described as an example of the edge extraction filter. However, the edge extraction filter is not limited to the sobel filter, and can be determined as appropriate. For example, the edge extraction filter may be a Prewitt filter.

  (2) In the above embodiment, the case where the intermediate edge image is binarized to generate a binary image and the number of edge pixels is specified from the generated binary image has been described as an example, but the binary image is not generated, The number of edge pixels may be directly specified from the intermediate edge image. In that case, the intermediate edge image corresponds to the edge image.

  (3) In the above-described embodiment, the case where the edge image is binarized to generate a binary image and the generated binary image is subjected to the white expansion process and the white contraction process has been described as an example. The process does not necessarily have to be performed. In this case, a binary image that has not been subjected to white expansion processing and white contraction processing corresponds to an edge image.

  (4) In the above embodiment, the case where the component E is sucked by the suction nozzle 24 is described as an example of holding the component E. However, the holding of the component E is not limited to this, for example, using a so-called chuck. You may hold | maintain by pinching the components E.

DESCRIPTION OF SYMBOLS 1 ... Surface mounter, 16 ... Board | substrate imaging camera (an example of an imaging part), 18 ... Component tape, 18B ... Housing recessed part, 25 ... Component supply position, 30 ... Control part, 55 ... Horizontal direction sobel filter (Horizontal edge) Example of extraction filter), 56... Vertical sobel filter (an example of vertical edge extraction filter), E... Component, P.

Claims (5)

A surface mounting machine for holding and mounting the component supplied by a component tape having a storage recess in which a component is stored and a component stored in the storage recess,
An imaging unit that images the housing recess and generates an image;
A control unit;
With
The controller is
Edge image generation processing for extracting an edge from the image and generating an edge image;
A specifying process for specifying the number of edge pixels that is the number of pixels corresponding to the edge of the edge image;
When the number of edge pixels is greater than or equal to a threshold, it is determined that there is a component, and when the number of edge pixels is less than the threshold, a determination process that determines that there is no component;
Run the surface mount machine. The surface mounter according to claim 1,
The control unit is a surface mounter that extracts edges by applying a horizontal edge extraction filter and a vertical edge extraction filter to the image in the edge image generation process. The surface mounter according to claim 1 or 2,
The control unit, in the edge image generation process,
An intermediate edge image generation process for generating an intermediate edge image by extracting an edge from the image;
A binary image generation process that binarizes the intermediate edge image to generate a binary image;
Edge expansion processing for expanding the edges of the binary image;
An edge contraction process for contracting edges of the binary image whose edges are expanded by the edge expansion process;
A surface mounter that generates the edge image by executing The surface mounter according to any one of claims 1 to 3,
The controller is
Performing a counting process for counting the number of times the component held in the receiving recess has failed to be held;
In the counting process, when it is determined by the determination process that there is no component, the surface mounter is excluded from the number of times of failure even if the component cannot be held. The surface mounter according to any one of claims 1 to 4,
The surface mounting machine, wherein the imaging unit images the housing recess next to the housing recess located at a component supply position that is a position where the component is supplied from the component tape to the surface mounting machine.

Images