JP4883636B2 - Electronic component orientation inspection apparatus, electronic component orientation inspection method, and electronic component placement machine - Google Patents

Description

  The present invention is an electronic device in which an upper surface of electronic components arranged and accommodated in a tray is imaged by a camera, and the captured image is processed to check whether the direction of the electronic component (up / down / left / right direction) is correct. The present invention relates to a component orientation inspection apparatus and an electronic component orientation inspection method.

  Electronic components supplied from the tray-type component supply device to the electronic component mounting machine are supplied in a state of being arranged and housed in the tray (see Patent Document 1). The electronic components in the tray are stored in a predetermined orientation, but in rare cases, they are stored in the wrong orientation. If an electronic component in the wrong direction is directly picked up by the suction nozzle of the electronic component mounting machine, the electronic component picked up by the suction nozzle (hereinafter referred to as “sucking component”) before mounting the electronic component on the circuit board. When recognizing the product type, shape, size, etc. of the suction component by taking a picture with a parts camera from below, if the shape of the suction component and the terminal arrangement are directional, the orientation of the suction component can be inspected. Although it is possible, it is impossible to inspect the orientation of the suction component with an image from the lower surface side of the suction component if the shape of the suction component and the terminal arrangement are not directional.

Therefore, there is a demand for the development of an inspection system that automatically inspects the direction of each electronic component in the tray from above before the electronic component in the tray is sucked by the suction nozzle.
JP 2005-353752

  In recent years, as an inspection system that inspects the orientation of electronic components in a tray with a camera from above, characters, symbols, designs, etc. representing the name of the product, manufacturer name, model number, etc. are displayed on the upper surface (black background) Focusing on the fact that the mark is drawn in white, the area where the mark is drawn is set as part data at a position shifted from the center of the upper surface of the electronic component, and the upper surface of the electronic component in the tray is captured by the camera. Then, the orientation of the electronic component in the tray can be inspected by comparing the average luminance (brightness) of the area with a mark determination threshold value and determining whether or not a mark exists in the area. It is considered.

  However, in the above inspection method, variations in the ground color on the top surface of the electronic component and variations in the color of the mark affect the determination accuracy, and the orientation of the electronic component may be erroneously determined.

  When stacking multiple trays on one pallet (see Patent Document 1), the distance between the electronic components in the uppermost tray and the camera / illumination light source varies depending on the number of trays stacked. Therefore, the focus of the camera is blurred or the brightness of the illumination on the top surface of the electronic component changes, which changes the brightness and contrast of the captured image, affecting the determination accuracy, and incorrectly determines the orientation of the electronic component. there's a possibility that.

  As a countermeasure, a height adjustment mechanism that moves the height position of the camera / illumination light source up and down according to the number of tray stacks is required to increase the cost, or to limit the number of tray stacks to an error. It is necessary to prevent judgment.

The present invention has been made in consideration of such circumstances. Therefore, the object of the present invention is to provide an inspection technique for improving the inspection accuracy of the orientation of the electronic components in the tray stacked on the pallet at a low cost. It is an object of the present invention to provide an electronic component orientation inspection apparatus and an electronic component orientation inspection method that can be realized without limiting the number of stacks.

In order to achieve the above object, the invention according to claims 1 and 3 images the upper surface of electronic components arranged and stored in trays stacked on a pallet with a camera, processes the captured image, and In the inspection of whether or not the orientation of the electronic component is correct, as an image processing target area, when the orientation of the electronic component is correct, marks such as characters, symbols, and symbols drawn on the top surface of the electronic component The first area where the mark exists and the second area where the mark does not exist are set, and the average luminance of each area or information correlated therewith (hereinafter collectively referred to as “intensity”) is calculated. Whether or not the electronic component is in the correct orientation depending on whether or not the brightness relationship between the bright area and the dark area is determined by comparing the brightness of the two areas. Inspected Is. Here, the first area may be set so that the entire mark exists, or may be set so that only a part of the mark exists.

Generally, the color of the mark is white, and the background color of the top surface of the electronic component is black. Therefore, the electronic components in the uppermost tray, the camera / illumination light source, and the number of trays stacked on the pallet Even if the interval of the camera changes, the camera is out of focus, the brightness of the illumination on the top surface of the electronic component changes, and the brightness or contrast of the captured image changes, the mark is present in the area where the mark exists. The relationship is brighter than the area that does not. Therefore, as in the present invention, the brightness of both the area where the mark exists and the area where the mark does not exist is obtained, and whether or not the positional relation between the brighter area and the darker area is determined. It is possible to accurately inspect whether or not the orientation of the electronic components in the tray stacked on the pallet is the correct orientation. In addition, the present invention does not require a height adjustment mechanism that moves the height position of the camera / illumination light source up and down in accordance with the number of trays stacked, and can meet the demand for cost reduction. There is no need to limit the number of loads, and productivity does not decrease.

  In this case, the camera used for the inspection of the electronic component may be newly provided with a dedicated camera. However, the mark camera provided in the electronic component mounting machine for identifying the circuit board positioning mark It is good to use. In this way, there is an advantage that it is not necessary to provide a new camera and further cost reduction is possible.

Hereinafter, an embodiment embodying the best mode for carrying out the present invention will be described.
First, the configuration of the tray-type electronic component supply apparatus will be described with reference to FIG.
Inside the main body box 11 of the tray-type electronic component supply apparatus, two magazines 12 and 13 configured to be able to be moved up and down independently are arranged up and down, and a plurality of slots provided in each magazine 12 and 13 A pallet 15 on which trays 14 in which electronic components are arranged and stored is stacked in one or more stages is stored.

  This tray-type electronic component supply apparatus is set and used in an electronic component mounter. During operation of the electronic component mounting machine, one of the two magazines 12 and 13 is stopped at the retracted position (the upper limit position or the lower limit position of the lifting range), and the other magazine is moved in the work area by the feed screw mechanism. The pallet 15 loaded with the electronic components requested from the electronic component mounting machine side is moved up and down to match the pallet loading / unloading position of the pallet drawing table 16, and the pallet 15 is moved to the magazine by a pallet loading / unloading mechanism (not shown) Are pulled out onto the pallet drawing table 16 and moved to the component suction station of the electronic component mounting machine, and the electronic components in the uppermost tray 14 on the pallet 15 are sucked by a suction nozzle (not shown) and placed on the circuit board. After mounting, when the uppermost tray 14 is out of parts, the uppermost tray 14 is automatically ejected, and the next Mounting an electronic component in the tray 14 (next uppermost) on a circuit substrate by suction by the suction nozzle.

  A control device (not shown) of the electronic component mounting machine is arranged and stored in the uppermost tray 14 before the electronic components in the uppermost tray 14 stacked on the pallet 15 are sucked by the suction nozzle. The upper surface of the electronic component is imaged by the camera 20, and the captured image is processed to function as inspection means for inspecting whether or not the electronic component is in the correct orientation. In this case, the camera 20 is a mark camera for identifying a positioning mark on the circuit board provided in the electronic component mounting machine, and the camera 20 is an XY robot (not shown) of the electronic component mounting machine. It is attached to and can move in the XY directions. An illumination light source (not shown) that illuminates the imaging target surface is attached to the camera 20.

  The control device of the electronic component mounting machine moves the camera 20 above the uppermost tray 14 before sucking the electronic components in the uppermost tray 14 stacked on the pallet 15 with the suction nozzle. While illuminating the upper surface of the electronic component in the uppermost tray 14 with the illumination light source, the upper surface of the electronic component is imaged. At this time, as the image processing target area, as shown in FIG. 2A, a first mark 21 such as a character, a symbol, or a pattern drawn on the upper surface of the electronic component when the orientation of the electronic component is correct exists. An area 22 and a second area 23 where the mark 21 does not exist are set, and the two areas 22 and 23 are stored in advance in a memory (not shown) of the control device as part data. Here, the first area 22 may be set so that the entire mark 21 exists, or may be set so that only a part of the mark 21 exists. In the example of FIG. 2, the two areas 22 and 23 are arranged in a vertical positional relationship, but may be arranged in a horizontal positional relationship.

  In the present embodiment, the two areas 22 and 23 have the same shape and size (number of pixels) and are arranged at point-symmetric positions with respect to the center of the upper surface of the electronic component. Therefore, as shown in FIG. 2B, when the orientation of the electronic component is reversed 180 ° by mistake, the mark 21 does not exist in the first area 22, and the mark is displayed in the second area 23. 21 will exist.

  When the electronic component is a square, the wrong direction can be not only 180 ° reversal but also 90 ° reversal and 270 ° reversal. Even in these cases, when the orientation of the electronic component is correct, a first area where at least a part of the mark on the upper surface of the electronic component exists and a second area where the mark does not exist are set, and the orientation of the electronic component is determined. Is wrong, the positions, shapes, and sizes of the two marks may be determined so that there is no mark in the first area and at least a part of the mark exists in the second area.

  In general, the color of the mark 21 is white and the background color of the upper surface of the electronic component is black. Therefore, the distance between the electronic component in the uppermost tray 14 and the camera 20 / illumination light source depends on the number of trays 14 stacked. Even if the focus of the camera 20 changes and the brightness of the illumination on the top surface of the electronic component changes, and the brightness and contrast of the captured image change, the mark 21 exists if the orientation of the electronic component is correct. The relationship that the first area 22 is brighter than the second area 23 where the mark 21 does not exist is maintained.

  Focusing on this point, in this embodiment, the average brightness of each area 22, 23 is calculated from the image of the upper surface of the electronic component captured by the camera 20, and the brightness of the two areas 22, 23 is compared. Thus, it is inspected whether the electronic component is in the correct orientation based on whether the positional relationship between the brighter area and the darker area is a determined positional relationship. In this case, in the example shown in FIG. 2, when the positional relationship between the brighter area and the darker area is correct as shown in FIG. If the darker area is the second area 23 located on the lower side in the first area 22 located at, it is determined that the mark 21 is in the correct positional relationship on the upper side, and the electronic Determine that the orientation of the component is correct. On the other hand, as shown in FIG. 2B, the brighter area is the second area 23 located on the lower side, and the darker area is the first area 22 located on the upper side. If so, it is determined that the position of the mark 21 is in the lower position and the electronic component is determined to be in the wrong direction.

  The electronic component orientation inspection process of the present embodiment described above is executed according to the electronic component orientation inspection routine of FIG. 3 by the control device of the electronic component mounter. This routine is performed every time the pallet 15 loaded with the tray 14 is pulled out from one of the magazines 12 and 13 of the tray type electronic component supply apparatus onto the pallet pulling table 16 or stacked on the pallet 15. Every time the uppermost tray 14 runs out of parts and the uppermost tray 14 is automatically ejected, the process is executed before the electronic components in the uppermost tray 14 are sucked by the suction nozzle.

  When this routine is started, first, in step 101, the luminance of each pixel in the first area 22 where the mark 21 exists when the orientation of the electronic component is correct is detected, and in the next step 102, the first area is detected. The average brightness L of the first area 22 is obtained by dividing the value obtained by integrating the brightness of each of the 22 pixels by the number of pixels in the first area 22.

  Thereafter, the process proceeds to step 103 where the brightness of each pixel in the second area 23 where the mark 21 does not exist when the orientation of the electronic component is correct is detected. In the next step 104, the brightness of each pixel in the second area 23 is detected. A value obtained by integrating the luminance is divided by the number of pixels of the second area 23 to obtain an average luminance D of the second area 23. Thereafter, the process proceeds to step 105, where the average brightness L of the first area 22 is compared with the average brightness D of the second area 23, and the average brightness L of the first area 22 is the average brightness of the second area 23. If it is determined that it is brighter than D, it is determined that the position of the mark 21 is the correct positional relationship on the upper side, and the process proceeds to step 106, where it is determined that the orientation of the electronic component is the correct orientation.

  On the other hand, if it is determined that the average luminance D of the second area 23 is brighter than the average luminance L of the first area 22, it is determined that the mark 21 is in the wrong positional relationship on the lower side. Then, the process proceeds to step 107, and it is determined that the orientation of the electronic component is abnormal (incorrect).

  When it is determined that the orientation of the electronic component is abnormal (incorrect), the determination direction may be rotated 90 degrees at a time and re-determined to detect which direction the electronic component is facing.

  It should be noted that a plurality of electronic components are accommodated within the field of view of the camera 20 and imaged in a lump, and the average luminance L, D of each area 22, 23 of the plurality of electronic components may be calculated from one image, It is also possible to capture only one electronic component within the field of view of the camera 20, and calculate the average luminance L, D of each area 22, 23 of one electronic component from one image. Alternatively, the areas 22 and 23 of one electronic component may be separately imaged, and the average luminance L and D of each area 22 and 23 of one electronic component may be calculated from two images.

  According to the present embodiment described above, the image processing target area is the first area 22 in which marks 21 such as characters, symbols, and symbols drawn on the upper surface of the electronic component exist when the orientation of the electronic component is correct. The second area 23 where the mark 21 does not exist is set, and the average luminance L, D of each area 22, 23 is calculated from the image of the top surface of the electronic component captured by the camera 20, and the two areas 22 are calculated. , 23 are compared to determine whether the orientation of the electronic component is correct depending on whether the positional relationship between the brighter area and the darker area is determined. Therefore, the distance between the electronic component in the uppermost tray 14 and the camera 20 / illumination light source varies depending on the number of stacked trays 14, and the focus of the camera 20 is blurred or the upper surface of the electronic component is Lighting brightness Even if the brightness and contrast of the captured image changes, the electronic component is correctly inspected based on the positional relationship between the brighter area and the darker area. Can do. In addition, the electronic component inspection system according to the present embodiment does not require a height adjustment mechanism that moves the height position of the camera 20 / illumination light source up and down in accordance with the number of stacks of trays 14, and thus requires a reduction in cost. In addition to being able to fill, there is no need to limit the number of trays 14 to be stacked, and productivity is not reduced.

  In this case, the camera 20 used for the inspection of the electronic component may be newly provided with a dedicated camera. However, as in the present embodiment, for positioning the circuit board provided in the electronic component mounting machine. If a mark camera for identifying a mark is used, there is an advantage that it is not necessary to provide a new camera and the cost can be further reduced.

  In this embodiment, the average brightness L and D of the areas 22 and 23 are calculated, respectively. However, if the sizes (number of pixels) of the two areas 22 and 23 are the same, the areas 22 and 23 are calculated. The integrated value of the luminance of all the pixels in the area may be used, or the number of pixels in which the luminance is greater than or equal to the predetermined value (or less than the predetermined value) in each of the areas 22 and 23 may be used. The average luminance or the information correlated therewith may be calculated.

  In addition, as shown in FIG. 2, when the two areas 22 and 23 have the same shape and size (number of pixels) and are arranged at point-symmetrical positions with respect to the center of the upper surface of the electronic component, only one area is included. May be specified as part data, and the other area may be calculated from the part data of one area.

  In addition, in the present invention, the shapes and sizes (number of pixels) of the two areas 22 and 23 may be different, and the two areas 22 and 23 are arranged at point-symmetric positions with respect to the center of the upper surface of the electronic component. Needless to say, various modifications can be made without departing from the spirit of the invention.

It is a side view of the tray type electronic component supply device in Example 1 of the present invention. (A) is a figure which shows the positional relationship of the mark of an electronic component upper surface when two directions of an electronic component are correct, and two areas, (b) is the mark of the electronic component upper surface when the direction of an electronic component is wrong It is a figure which shows the positional relationship of 2 areas. It is a flowchart explaining the flow of a process of an electronic component direction test | inspection routine.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Main body box, 12 ... Main magazine, 13 ... Sub magazine, 14 ... Tray, 15 ... Pallet, 16 ... Pallet drawer table, 20 ... Camera, 21 ... Mark, 22 ... First area, 23 ... Second area

Claims (4)

A camera for imaging the upper surface of electronic components arranged and stored in trays stacked on a pallet;
In an electronic component orientation inspection apparatus comprising an inspection unit that processes an image of an electronic component upper surface imaged by the camera and inspects whether the orientation of the electronic component is a correct orientation,
The inspection means includes, as an image processing target area, a first area in which marks such as characters, symbols, symbols, and the like drawn on an upper surface of the electronic component exist when the orientation of the electronic component is correct, and the mark does not exist The second area is set, the average luminance of each area or information correlated therewith (hereinafter collectively referred to as “intensity”) is calculated, and the intensities of the two areas are compared and brightened. Electronic component orientation inspection apparatus for inspecting whether or not the orientation of the electronic component is correct depending on whether the positional relationship between the darker area and the darker area is a determined positional relationship .   2. The electronic component orientation inspection apparatus according to claim 1, wherein the camera is a mark camera provided in an electronic component mounting machine for identifying a positioning mark on a circuit board. An electronic component orientation in which the upper surface of electronic components arranged and stored in trays stacked on a pallet is imaged with a camera, and the captured image is processed to check whether the electronic component is in the correct orientation In the inspection method,
As an image processing target area, when the orientation of the electronic component is correct, a first area where characters, symbols, symbols, and the like drawn on the upper surface of the electronic component are present, and a second area where the mark is not present Is set, and the average luminance of each area or information correlated therewith (hereinafter collectively referred to as “intensity”) is calculated, and the intensities of the two areas are compared with the darker areas. An electronic component orientation inspection method comprising: inspecting whether the orientation of the electronic component is a correct orientation based on whether the positional relationship with the other area is a determined positional relationship.   An electronic component mounting machine comprising the electronic component orientation inspection apparatus according to claim 1.

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