JP4331981B2 - Calibration method and apparatus for component mounting machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a calibration method and apparatus for a component mounter, and more particularly, to a calibration method and apparatus for a component mounter that calibrates the moving origin of a head unit that picks up a component to the origin at the time of manufacture.
[0002]
[Prior art]
In the component mounting machine, the head unit is moved to the component supply unit by the XY robot to suck the component, and then the head unit is moved to a predetermined position on the circuit board to mount the sucked component on the circuit board. The component suction position and mounting position are described as coordinate values in the component data with reference to the origin of the component mounter, so if the origin that is the head movement reference differs from the component data origin, the suction position, The mounting position is different from the actual one and accurate component mounting is not guaranteed. Therefore, an origin mark is provided on the base of the component mounter, which is the origin of the component data, and calibration is performed at a predetermined time point so that the movement origin of the head unit and the origin of the component data coincide with each other. It is increasing.
[0003]
Conventionally, in order to perform such calibration, an imaging device is mounted on the head, the origin mark on the upper surface of the mounting machine base is recognized, and the acquired position is used as the calibration origin (movement origin of the head). It was.
[0004]
Also known is a method of calibrating the head unit by mounting a jig on the head unit, moving the head unit to an imaging unit fixed to the mounting machine, imaging the jig, processing the image, and so on. (Patent Document 1).
[0005]
[Patent Document 1]
JP 2001-223499 (paragraphs [0029] to [0031]).
[0006]
[Problems to be solved by the invention]
However, in the conventional method of performing calibration of the mounting machine by recognizing the origin mark by the imaging device mounted on the head unit, the origin mark is recognized based only on information described at the time of manufacture. When the origin mark is deteriorated and deformed, or when foreign matter is mixed in the origin mark, the origin mark cannot be accurately recognized, and accurate calibration cannot be performed.
[0007]
The present invention has been made to solve such a problem, and performs a calibration method with high reliability and accuracy, and a component mounting machine calibration method and apparatus capable of improving component mounting accuracy. It is an issue to provide.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, the present invention
In the calibration method of the component mounting machine for calibrating the movement origin of the head portion to the origin of the component mounter during manufacture of adsorbing components,
Up to the component mounting machine during manufacture, the image captured at the origin calibration marks as the first image, the image is an image parameter of its area, the radius, diameter, the difference in radius between the maximum value and the minimum value, the diameter of the Find at least one of the difference between the value and the minimum value,
During calibration, imaging the origin mark the image as a second image, for the same image parameters from the first image,
At the time of calibration, template matching with the second image is performed using the first image as a template, or the image parameters of the first and second images are compared,
Whether the correlation value of the template matching exceeds a predetermined correlation value or the difference between the image parameters is within a preset allowable range, so that the origin mark imaged at the time of calibration is the origin mark at the time of manufacture Determine whether
A configuration is adopted in which when the origin mark is determined, the position of the origin mark is used as the moving origin of the head unit.
[0009]
In the present invention,
In the calibration device of the component mounting machine for calibrating the movement origin of the head portion to the origin of the time of component mounting apparatus manufacturing of adsorbing components,
An imaging device for imaging the calibration origin mark;
Up to the component mounting machine during manufacture, the image captured at the origin calibration marks as the first image, the image is an image parameter of its area, the radius, diameter, the difference in radius between the maximum value and the minimum value, the diameter of the Storage means for determining at least one of a difference between the value and the minimum value and storing the first image and its image parameter;
During calibration, the image captured the origin mark as a second image, for the same image parameters from the first image, or to perform template matching between the second image of the first image as a template, Or means for comparing the image parameters of the first and second images;
Whether the correlation value of the template matching exceeds a predetermined correlation value or the difference between the image parameters is within a preset allowable range, so that the origin mark imaged at the time of calibration is the origin mark at the time of manufacture Determination means for determining whether or not,
A configuration is also employed in which when the origin mark is determined, the position of the origin mark is set as the moving origin of the head unit.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.
[0011]
FIG. 1 is a schematic front view of the component mounting machine 1, and FIG. 2 is a block diagram of its control system. In FIG. 1, the component mounting machine 1 is provided with a head portion 2 on which a suction nozzle 3 is mounted. The head portion 2 is moved in the X-axis and Y-axis directions by an XY drive unit 4. An imaging device 5 composed of a CCD camera or the like is fixed to the head unit 2, and this imaging device 5 is an origin mark attached to a calibration unit 6 installed on the base frame of the component mounting machine 1. 7 is imaged. A component recognition camera 8 that captures an image of the component 9 sucked by the suction nozzle 3 is attached to the base of the component mounting machine 1.
[0012]
As shown in FIG. 2, the XY drive unit 4 includes a controller 10 including a CPU, a ROM, a RAM, and the like, and an X-axis motor 11 and a Y-axis motor 12 that are driven under the control of the controller 10. The head unit 2 is driven by the X-axis motor 11 and the Y-axis motor 12 and moved in the XY directions. Further, the suction nozzle 3 attached to the head unit 2 is moved up and down by a Z-axis motor 13 driven under the control of the controller 10 and rotated around the suction shaft by a θ-axis motor 14. .
[0013]
The image of the component 9 captured by the component recognition camera 8 and the image of the origin mark 7 captured by the imaging device 5 are input to the image processing device 17. The image processing device 17 includes a CPU 17a, a memory 17b, an A / D converter 17c, and the like. The CPU 17a processes the image of the component 9 to recognize the component posture, and the captured image of the origin mark 7 is displayed. Process to recognize the position of the origin mark.
[0014]
Further, the component mounter 1 is provided with input devices such as an origin mark data and a keyboard 15 and a mouse 16 for inputting component data. These input data are constituted by a hard disk, a flash memory, or the like. Stored in the storage device 18. In addition, the component mounter is provided with a monitor 19, and on this screen, an image of a component captured by the component recognition camera 8 and an image of an origin mark captured by the imaging device 5 can be displayed. .
[0015]
When mounting a component on a circuit board (not shown) with such a configuration, the head unit 2 is moved to the component supply unit by the XY drive unit 4, and the component 9 supplied therefrom is sucked by the suction nozzle 3. Then, it moves onto the component recognition camera 8, where the component 9 is imaged by the component recognition camera 8. The image of the component 9 is processed by the image processing device 17, and the component displacement (shift between the suction center and component center and angular displacement) is calculated. Thereafter, the head unit 2 moves to the circuit board. In this case, the positional deviation is corrected and the component 9 is mounted at a predetermined position on the circuit board.
[0016]
Since the component suction position and the mounting position are described in the component data as coordinate values with the origin mark 7 on the component mounter 1 as a reference (origin), the origin serving as the movement reference of the head unit 2 is the component data. Since the component mounting accuracy deteriorates if it is different from the origin of the above, in the present invention, calibration is performed at predetermined time points or at predetermined time points such as when the power is turned on, at the start of board production, or at the time of specified component mounting. To compensate. Hereinafter, the calibration method will be described.
[0017]
FIG. 3 shows the flow of processing at the time of manufacturing the component mounter. The head unit 2 is driven by the XY drive unit 4 so that the head unit 2 is placed on the origin mark 7 on the base frame of the component mounter. (Step S1), and the origin mark 7 is imaged by the imaging device 5 (step S2). The captured image of the origin mark 7 is converted into a digital signal by the A / D converter 17c of the image processing device 17, and then stored in the memory 17b. The image is processed, and each data of the origin mark 7 is calculated ( Step S3).
[0018]
As shown in FIG. 5A, the origin mark 7 is, for example, a circular mark having a diameter of about 1.5 mm. Therefore, the diameter and radius for each direction are obtained. For example, each radius R1 (θn) and radius R2 (θn) in the direction extending at an angle θn with respect to the Y axis is obtained, and θn is set in units of 1 degree from 0 degrees to 359 degrees (θn = 0, 1, 2, ... 359 degrees). Note that this angle setting is arbitrary, and the angle θn can be set not every 1 degree but coarser, for example, every 2 degrees, or finer, for example, the angle θn can be set every 0.5 degrees. It can also be set. When set in units of 1 degree, 360 types of radii R1 (θn) and radius R2 (θn) can be obtained, and the radii R1 and R2 at the respective angles, the diameter R1 + R2, and the area of the origin mark are determined. calculate. In addition, as the area, an average value of diameters in each direction is obtained, and a value calculated as an area of a circle having the diameter is used.
[0019]
From the radius and the diameter thus obtained, the difference between the maximum value MAX and the minimum value MIN of the diameter and the difference between the maximum value MAX and the minimum value MIN of the radius are obtained. The determination of the origin mark at the time of manufacture is OK, and the image data of the origin mark and the radii R1 (θn) and R2 at each angle obtained in step S3 are stored in the memory 17b or the storage device 18 of the image processing device 17. (Θn) and diameter R1 (θn) + R2 (θn), and data of each image parameter of the area and the difference between both are stored (steps S4 and S5), while the maximum of diameter R1 (θn) + R2 (θn) If any of the difference between the value MAX and the minimum value MIN and the difference between the maximum value MAX and the minimum value MIN of the radii R1 (θn) and R2 (θn) exceeds a predetermined threshold, Manufacturing defect Thus, the abnormality is displayed and the adoption as the origin mark is stopped (steps S4 and S6).
[0020]
FIG. 4 shows a flow when calibrating the XY drive unit 4 and the head unit 2 driven by the XY drive unit. The calibration is usually performed when the component mounter system is started up, but can also be performed for each production board or when a specified component is mounted.
[0021]
In the calibration process, first, the head unit 2 is driven by the XY drive unit 4, and the imaging device 5 attached to the head unit 2 is moved onto the origin mark 7 of the calibration unit 6 (step S11). The origin mark 7 is imaged by the device 5 (step S12). The captured image of the origin mark is input to the image processing device 17 and stored in the memory 17b. The origin mark image acquired at the time of manufacture (hereinafter referred to as the first image) and the origin mark acquired at the time of calibration are obtained. Are compared (hereinafter, second image) (step S13).
[0022]
In this comparison, since the first image is stored in the memory 17b or is read from the storage device 18 and loaded into the memory 17b, the first image is used as a template and the second image Template matching is performed, and the correlation value is obtained. Further, as determined for the first image, the image parameters for the second image, that is, radius R1 (θn) and radius R2 (θn) in each direction θn, and diameter R1 (θn) are also obtained. + R2 (θn), average value of diameter R1 (θn) + R2 (θn), radius R1 (θn), average value of R2 (θn), circle area obtained from average value of diameter, diameter R1 (θn) + R2 ( The difference between the maximum value MAX and the minimum value MIN of θn) and the difference between the maximum value MAX and the minimum value MIN of the radii R1 (θn) and R2 (θn) are calculated, and the image parameter data of these second images are The image parameter data of one image is compared.
[0023]
From these comparisons, the correlation value obtained by template matching between the first and second images exceeds a predetermined correlation value, or the area difference (first difference) between the first and second images is the first image. The difference between the average value of the diameters R1 (θn) + R2 (θn) and the average value of the diameters R1 (θn) + R2 (θn) of the second image (second difference), the diameter R1 of the first image (θn) ) Difference between the maximum value MAX and minimum value MIN of + R2 (θn) and the difference between the maximum value MAX and minimum value MIN of the diameter R1 (θn) + R2 (θn) of the second image (third difference), The difference (fourth difference) between the average value of the radius R1 (θn) and radius R2 (θn) of the first image and the average value of the radius R1 (θn) and radius R2 (θn) of the second image, The difference between the maximum value MAX and the minimum value MIN of the radii R1 (θn) and R2 (θn) of the first image and the radius R1 (θn) of the second image If any of the differences (fifth difference) between the maximum value MAX and the minimum value MIN of R2 (θn) is within the allowable range, it is determined that the mark imaged in step S12 is the origin mark. Then, the XY drive system is controlled using the center of the mark as the movement origin of the XY drive unit 4 or the head unit 2 driven by this unit (steps S14 and S15). As a result, the head unit 2 moves to the component supply unit to suck the component, corrects the posture of the component, and mounts the component on the substrate.
[0024]
On the other hand, if the correlation value does not exceed the predetermined correlation value and any one of the first to fifth differences is not within the allowable range, it is determined that the mark imaged in step S12 is not the origin mark. Then, the mounting machine stops, issues an alarm, and waits for the operator's judgment (steps S14 and S16).
[0025]
For example, as shown in FIG. 5B, when relatively large dust having different reflectivity or dust 7 'is deposited on the origin mark 7, the correlation value is small and predetermined. The correlation value is not exceeded, and there is a high possibility that any of the first to fifth differences is not within the allowable range, so it cannot be used as the origin mark, but is shown in FIG. Thus, when relatively small dust or dust 7 ″ is accumulated on the origin mark 7, the third difference and the fifth difference are not within the allowable range, but other differences are within the allowable range. Since the correlation value is likely to exceed the predetermined correlation value, it can be determined as the origin mark.
[0026]
In the above-described embodiment, the correlation value between the first and second images exceeds a predetermined correlation value, or one of the first to fifth differences between the first and second images is allowed. The mark taken during calibration is determined to be the origin mark when the condition of being within the range is satisfied, but it can be determined to be the origin mark when all of the conditions are satisfied. it can. As a result, as shown in FIG. 5C, when even a small amount of foreign matter adheres to the origin mark, it can be excluded to use it as the origin mark, and calibration can be performed more strictly. In addition to satisfying any one of the conditions instead of such a strict condition, the origin mark can be determined when one or more of the other conditions are satisfied.
[0027]
In the embodiment described above, the origin mark is circular, but may be other shapes such as an ellipse or a rectangle. The data acquisition and determination conditions are changed according to the shape to be adopted. For example, in the case of a rectangle, two orthogonal sides are used instead of the radius and the diameter.
[0028]
【The invention's effect】
As described above, according to the present invention, since the calibration with high reliability can be performed, the component mounting accuracy can be improved, and the quality of the origin mark at the time of manufacture is determined. Therefore, the calibration accuracy can be improved.
[Brief description of the drawings]
FIG. 1 is a front view showing a schematic configuration of a component mounter.
FIG. 2 is a block diagram showing a configuration of a control system of the component mounter.
FIG. 3 is a flowchart showing a flow of acquiring an origin mark image at the time of manufacturing;
FIG. 4 is a flowchart showing a flow of determining an origin mark during calibration.
FIG. 5 is an explanatory diagram showing the shape of an origin mark.
[Explanation of symbols]
2 Head unit 5 Imaging device 6 Calibration unit 7 Origin mark 17 Image processing device

Claims (2)

In the calibration method of the component mounting machine for calibrating the movement origin of the head portion to the origin of the component mounter during manufacture of adsorbing components,
Up to the component mounting machine during manufacture, the image captured at the origin calibration marks as the first image, the image is an image parameter of its area, the radius, diameter, the difference in radius between the maximum value and the minimum value, the diameter of the Find at least one of the difference between the value and the minimum value,
During calibration, imaging the origin mark the image as a second image, for the same image parameters from the first image,
At the time of calibration, template matching with the second image is performed using the first image as a template, or the image parameters of the first and second images are compared,
Whether the correlation value of the template matching exceeds a predetermined correlation value or the difference between the image parameters is within a preset allowable range, so that the origin mark imaged at the time of calibration is the origin mark at the time of manufacture Determine whether
A component mounting machine calibration method, characterized in that when it is determined to be an origin mark, the position of the origin mark is set as a moving origin of the head portion. In the calibration device of the component mounting machine for calibrating the movement origin of the head portion to the origin of the time of component mounting apparatus manufacturing of adsorbing components,
An imaging device for imaging the calibration origin mark;
Up to the component mounting machine during manufacture, the image captured at the origin calibration marks as the first image, the image is an image parameter of its area, the radius, diameter, the difference in radius between the maximum value and the minimum value, the diameter of the Storage means for determining at least one of a difference between the value and the minimum value and storing the first image and its image parameter;
During calibration, the image captured the origin mark as a second image, for the same image parameters from the first image, or to perform template matching between the second image of the first image as a template, Or means for comparing the image parameters of the first and second images;
Whether the correlation value of the template matching exceeds a predetermined correlation value or the difference between the image parameters is within a preset allowable range, so that the origin mark imaged at the time of calibration is the origin mark at the time of manufacture Determination means for determining whether or not,
A calibration apparatus for a component mounting machine, wherein when it is determined that the mark is an origin mark, the position of the origin mark is set as a moving origin of the head unit.

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