JPH03241897A - Positional correction of component - Google Patents

Abstract

PURPOSE:To enable a component to be accurately positioned by a method wherein a reference mark is provided to a part of a transfer device other than a component which confronts an image input device, and the position of the component is corrected basing on the positional relation between the center position of the component obtained on an image and the position of the reference mark. CONSTITUTION:A reference mark 2b is formed on the face of a transfer device 2 which confronts an image input device 4, where the mark 2b is provided in such a manner that it is prevented from overlapping a component 1 when the component 1 is sucked by a suction head 2a. An image input device 4 have a field of view large enough to pick up the component 1 and the reference mark 2b at a time, an obtained image is inputted into a control device 5 and processed to obtain an image correspondent to the component 1 and the reference mark 2b. Then, on the image, the coordinates (x1, y1) of the center O1 of the reference mark 2b and the coordinates (x2, y2) of the center O2 of the component 1, and the deviation of the center O2 of the component 1 from the center O3 of a suction head 2a is accurately obtained.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a component position correction method that enables accurate positioning of a mounting position on a circuit board, mainly during the process of transferring surface-mounted components to a circuit board.

[Conventional technology]

Generally, when automatically mounting components onto a circuit board, the components are picked up from a feeder that supplies the components using a transfer device equipped with a suction head, and the components are sucked to the mounting position set on the circuit board. Transport and install. In this mounting method, the relative position between the transfer device and the component is not necessarily constant, so it is necessary to correct the relative position of the transfer device with respect to the mounting position on the circuit board based on the relative position between the transfer device and the component. be. In particular, when a surface-mounted component with a large number of leads is used, the pitch between adjacent leads is small, and even a slight misalignment can lead to wiring errors. Therefore, in order to prevent wiring errors, the position of the component relative to the transfer device is detected during the process of transferring the component using the transfer device, and the positional deviation of the component being transferred is corrected according to the detected position of the component. The idea is to accurately align the mounting position using As a method of detecting the position of a component in such a component position correction device, a method of detecting the position of the component based on an image of the component lead has been proposed (Japanese Patent Laid-Open No. 63-88896).
No. Publication〉.

[Problems to be Solved by the Invention] By the way, even if the position of a component on the image can be accurately detected based on the image from the human-powered imager, the relative position between the suction head of the transfer device and the component cannot be accurately detected. If this is not known, a problem arises in that an accurate correction amount for correcting the position of the component cannot be obtained, and the component cannot be accurately positioned at the mounting position on the circuit board. The present invention is aimed at solving the above-mentioned problems, and is a part position correction method that makes it possible to determine an accurate positional relationship between a transfer device and a part, and thereby enables accurate positioning of the part. It is intended to provide a method. [Means for Solving the Problems Pi1] In order to achieve the above objectives, in the present invention, in the process of transferring the components to the mounting position on the circuit board by the transfer device, the components are imaged by the #I image input device, and the In a component position correction method that controls a transfer device to correct the position of the component relative to a mounting position on a circuit board based on the position of the component on an image obtained by an input device, the transfer device includes an image human-powered device; A reference mark is formed at a location opposite to the part on the opposite surface of the part, and a correction amount for correcting the position of the part is determined based on the position zm relationship between the center position of the part and the reference mark obtained on the above image. -ing [Operation] According to the above method, since the image input device captures an image of the reference mark provided on the transfer device together with the component, by determining the relative position between the reference mark and the center position of the component on the image, the transfer device The positional relationship between the component and the component can be determined accurately, and the correct amount of correction of the component position relative to the mounting position can be determined. As a result, the accuracy of component positioning increases.

【Example】

The component 1 used in this embodiment is for surface mounting, and has a shape in which a plurality of leads 1b are protruded from each of 4M of a package 1a formed in the shape of a rectangular parallelepiped.
It is sucked by the suction head 2a of the transfer device 2 and taken out from the feeder, tray, etc. at position 2 in FIG. 2, transferred to position 2 in FIG. In addition, at position ■ in the transfer process by the transfer device W2, I
The component 1 is imaged by an image input device 4 such as a TV camera, and as shown in FIG. The position of part 1 is determined, and
The position of the component 1 is corrected according to the position so as to match the mounting position. By the way, as shown in FIG. 1, the transfer device W2 has a reference mark 2b formed on the surface facing the image input device 4. This reference mark 2b has a fixed position with respect to the center position of the suction head 2a', and is provided at a position that does not overlap with the component 1 when the component 1 is suctioned by the suction head 2a. The iI image input device 4 has a field of view large enough to simultaneously image the component 1 and the reference mark 2b, and the obtained image is input to the control device W5. The control device 5 performs well-known W-processing such as binarization and thinning on the image captured by the image input device 4, and as shown in FIG. so that you can get the image you want. Further, in order to obtain such an image, the illumination at the time of imaging with the image input device 4 is taken into consideration. Next, on the image as shown in FIG. 3, the φ center of the reference mark 2b is 0. coordinates OC++3'+) and the center O1 of part 1
The coordinates (X z + y2) of Center 0 of reference mark 2b. For this purpose, a method such as determining the center of gravity of the image of the reference mark 2b may be used.
For example, the method shown in FIG. 5 and FIG. Find the midpoint of the sequence. This includes the center point a of the lead 1b for each side of the package 1a.
The average value of the X coordinate and the average value of the Y coordinate of ~p are determined, respectively, and the average value is set as the coordinates of the midpoints q to t of the arrangement of the leads 1b on each side of the package 1a. Next, a straight line i connecting the midpoints q~ of opposite sides
Find the intersection of t and 12, and place this intersection at the center O8 of part 1.
and the coordinate axes set in the image and the above straight line 1. ．． 1
．． Let the angle of intersection with this be the inclination angle θ of the component 1. In the manner described above, the coordinates of the center 01 of the reference mark 2b and the coordinates of the center 02 of the component 1 are determined. Note that, based on the midpoints a to p of each lead 1b, the package 1a
Although the midpoints q to t of the arrangement of the leads 1b on each side are determined, it goes without saying that other representative points, such as the midpoint of the tip edge of each lead 1b, may be used. Center 0 of reference mark 2b. Since the displacement Ji (Δx11.ΔyI3) between the coordinates (x+, y+) of and the coordinates (xi, yi) of the center O1 of the suction head 2a is predefined, (Xy
+) is determined, the coordinates (X3.y3) of the center O of the suction head 2a are determined as follows. Also, the coordinates (x
z, yz), the positional relationship between the center O1 of the suction head 2a and the center 02 of the component 1 (mu
) is ΔX :X 2 based on the suction head 2a side
It is given by (X++muXl3)=ΔX12−muX13 Δy=y2−(y++muymouth)=Δ3'+2−Δy1. However, Mux12=x, -X+, ΔyI
2-'j2'! Even though the image of the center O1 of the suction head 2a cannot be obtained by using +1 or more, the coordinates of the center 0 of the suction head 2a (X3.y3 ) can be determined accurately, and as a result, the center O of the suction head 2a
The deviation of the center 02 of the component 1 from the center 02 of the component 1 can be accurately determined. That is, FIG. 4 shows the operation of determining the correction amount in a manner greater than or equal to 0, which allows obtaining an accurate correction amount so that the component 1 can be accurately positioned at the mounting position on the circuit board 3.

【Effect of the invention】

As described above, the present invention images the component by an image input device during the process of transferring the component to the mounting position on the circuit board by the transfer device, and based on the position of the component on both images obtained by the image input device. In a component position correction method for controlling a transfer device to correct the position of a component relative to a mounting position on a circuit board using , the amount of correction for correcting the position of the part is determined based on the positional relationship between the center position of the part and the reference mark obtained on the image, and the image input device is configured to determine the amount of correction for the position of the part. Since the set reference mark is imaged, by determining the relative position between the reference mark and the center position of the component on the image, the positional relationship between the transfer device and the component can be accurately determined, and the relative position relative to the mounting position can be determined. It is possible to obtain an accurate correction amount for the position of the component. As a result, there is an effect that the precision of positioning the parts is increased.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention, FIG. 2 is an operational explanatory diagram showing a component mounting process in the same, and FIGS. 3 to 6 are operational explanatory diagrams in the same. DESCRIPTION OF SYMBOLS 1... Part, 1a... Package, 1b... Lead, 2... Transfer device, 2a... Suction head, 2b...
...Reference mark, 3...Circuit board, 4...Image input device, 5...Control device.

Claims (1)

[Claims] (1) During the process of transferring the component to the mounting position on the circuit board using the transfer device, the component is imaged by the image input device, and the component is mounted on the circuit board based on the position of the component on the image obtained by the image input device. In a component position correction method that controls a transfer device to correct the position of the component relative to the position, a reference mark is formed in a part of the transfer device that is different from the component on a surface facing an image input device, and the reference mark is 1. A method for correcting the position of a component, comprising determining a correction amount for correcting the position of the component based on the positional relationship between the center position of the component and a reference mark.