JPH06139335A - Method for correcting coordinate data of electronic parts mounting device - Google Patents

Abstract

PURPOSE:To easily correct parts mounting position coordinate data. CONSTITUTION:The substrate pattern in the position where parts should be mounted is photographed and its coordinate data is calculated (S11). It is discriminated whether coordinate data of a pad position of the substrate pattern coincides with parts mounting position coordinate data or not (S12); and if they do not coincide with each other, parts mounting position coordinate data is corrected (S13). When confirmation and correction of coordinate data of all parts mounting positions are completed (YES in S16), mounting of parts is tried based on coordinate data (S18). Mounted parts are photographed by a camera and coordinate data of mounted parts is calculated (S19). Difference data between both coordinate data is calculated (S20), and parts mounting position coordinate data is corrected by this difference data (S21).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to resistors, capacitors, I
The present invention relates to a coordinate data correction method for an electronic component mounting apparatus that mounts an electronic component such as C on a substrate.

[0002]

2. Description of the Related Art The electronic component mounting apparatus for mounting chip components such as resistors, capacitors, and ICs on a substrate is
For example, having a mounting work head that can move in the X and Y directions,
The mounting work head is provided with a suction nozzle that sucks a component. This suction nozzle picks up an electronic component from the component supply cassette, moves it to the component mounting position, and mounts the component at that position.

By the way, in order to mount a component by the electronic component mounting apparatus, it is necessary to previously input coordinate data designating the mounting position of each component on the board. The coordinate data can be input by actually measuring the mounting position on the board and inputting it as coordinate data, by inputting the coordinate data of each part from the digitizer, or by directly designing the CAD data, which is the design data of the board pattern, as coordinate data. There is a method to input as.

The method of measuring the mounting position of the board and inputting it as coordinate data has a problem that a mounting error occurs between the mounting position of the electronic component and the position of the pattern of the board due to a measurement error.

In the method of inputting the mounting position of a component by the digitizer, since the operator specifies the coordinate position, an error occurs in the input coordinate due to human visual recognition error or the like. Also, due to the error between the digitizer coordinates and the component mounting device coordinates,
There is a problem that the pad position of the board pattern and the mounting position of the component are displaced.

In the method of inputting the CAD data as the coordinate data, the human error is eliminated, but the deviation between the pad position and the component mounting position due to the error between the CAD coordinate and the component mounting device coordinate is not eliminated.

Therefore, conventionally, as shown in the flow chart of FIG. 3, after the coordinate data of the component to be mounted is input (FIG. 3, S1), the component is mounted on the board based on the coordinate data (S2), Whether each component is mounted on a predetermined pad position (a portion of the board pattern to be soldered) is confirmed visually or by a magnifying glass (S3), and if the mounting position is displaced, the displacement amount is measured. The coordinate data was corrected by the amount of deviation (S4). Then, after the component is mounted again (S5), the process returns to step S3 to confirm the mounting position of the component and correct the coordinate data.

Usually, before starting the mounting of the parts, it is necessary to repeat the above-mentioned work such as the trial mounting of the parts, the confirmation of the mounting position, the correction of the coordinate data, etc., which requires a long working time. There is a problem that skill is required to correct the coordinate data from the displacement amount of the mounted components.

Even if there is no deviation between the input coordinate data and the pad position on the substrate, if there is eccentricity of the shaft to which the suction nozzle is attached, bending of the suction nozzle, etc., the same as described above. Moreover, there arises a problem that the mounting position of the component is displaced from the pad of the substrate.

In any case, in the conventional electronic component mounting apparatus, the component is actually mounted according to the coordinate data set and the displacement amount of the component is measured, and the operator corrects the coordinate data by the displacement amount. There was a need.

[0011]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a coordinate data correction method capable of easily correcting component mounting position coordinate data.

[0012]

The gist of the present invention is to capture the image of the pattern of the board and the components mounted on the board, perform image recognition to calculate the coordinate positions of each, and shift the position of the mounted component with respect to the coordinate position of the board pattern. The amount is calculated and the component mounting position coordinate data is corrected by the difference data between the two.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. The electronic component mounting apparatus of one embodiment of the present invention has a mounting work head movable in the X-axis and Y-axis directions, which is not particularly shown, and a component is provided by a suction nozzle provided in the mounting work head. The component is picked up from the supply cassette and placed at the position specified by the coordinate data.

Further, a board photographing camera is provided integrally with the working head, and as will be described later in detail, before the mounting of the parts is started, the board pattern pad (solder the pattern parts Parts to be attached) and components mounted for trial, image data of each is obtained, image recognition processing is performed on the image data, and pad positions and component mounting positions are calculated.

A component photographing camera is provided at a predetermined position below the mounting work head, and the component photographing camera photographs the component picked up by the suction nozzle to obtain image data indicating the suction state of the component. Then, the image data is subjected to image recognition processing to calculate the shift amount of the component suction position,
At the time of mounting the component, the component is mounted at a desired position by correcting the displacement amount of the component suction position.

Next, a method of correcting coordinate data in the electronic component mounting apparatus having the above-described structure before starting the mounting of the component on the board will be described with reference to the flowchart of FIG. The following processing is executed by a central processing unit (not shown) in the electronic component mounting device. Further, it is assumed that the coordinate data of the components to be mounted have been input in advance by a digitizer or the like.

First, in step S11 of FIG. 1, the pad position of the board pattern is photographed by the board photographing camera based on the coordinate data and is displayed on the CRT. At this time, since the mounting positions of the components based on the coordinate data (design data) input in advance are simultaneously displayed on the CRT, in the next step S12, it is determined whether or not they match on the screen. to decide.

When the pad position (center of the pad or predetermined area of the pad) of the board pattern photographed by the camera coincides with the component mounting position based on the coordinate data, the process directly proceeds to step S14 and the coordinate data of the mounting point is stored. To do. On the other hand, when the pad position photographed by the camera does not match the mounting position based on the coordinate data, step S13
Align the cursor with the center of the pad of the board pattern (see Fig. 2 (a)), and set the coordinate data of that point as the coordinate data of the component mounting point.

If the coordinate data of the bad position photographed by the camera does not match the component mounting position coordinate data, the coordinate data may be automatically corrected without moving the cursor.

When the processing of steps S11 to S14 is completed, the process proceeds to step S15, after the coordinate data is changed to the next mounting point, and in step S16, the confirmation and correction processing of the coordinate data is completed for all the component mounting points. Determine whether or not. If the confirmation and correction processing of the coordinate data has not been completed, the process returns to S11 and the above processing is repeated for the next mounting point.

When all the mounting points on the board are confirmed and corrected and the coordinate data is corrected, the coordinate data corrected in step S17 is stored in the first storage unit of the memory (not shown). .

Next, in step S18, each component is mounted on the board based on the above coordinate data. In this case, the mounting position coordinate data of the board is corrected based on the coordinate data of the pad position of the board pattern obtained by photographing the board pattern with the board photographing camera, and the component is mounted on the board based on the corrected coordinate data. Since it is mounted, the deviation of the board pattern from the design data is corrected at that time.

Next, in step S19, the electronic parts mounted on the board are sequentially photographed by the board photographing camera, image recognition processing is performed, and the coordinate data of the mounting position of each component (hereinafter referred to as actual coordinate data). ) Is calculated. As a method of calculating the actual coordinate data, for example, the coordinate data of the center position of the image of the electronic component obtained by the image recognition is calculated in the X / Y coordinate system whose origin is the reference position of the board. When the image of the electronic component is arranged at a certain angle with respect to the reference coordinate system, the X / Y coordinates and the angle θ thereof are stored as coordinate data.

Next, in step S20, the actual coordinate data obtained by recognizing the image of the part is subtracted from the coordinate data stored in the first storage section to obtain difference data between the two, and in step S21 the difference data is obtained. The result of addition to the coordinate data is stored in the first storage unit. As a result, the component mounting position coordinate data is corrected by the amount of displacement of the component mounting position.

For example, if the components shown in FIG. 2 (b) are image-recognized and the mounted component real coordinate data is calculated, the real coordinate data is subtracted from the pad position coordinate data to determine the difference between the two. By obtaining the data ΔX and adding the difference data ΔX to the coordinate data, the coordinate data can be corrected by the amount of deviation of the mounting position of the component.

According to this embodiment, since the coordinate data is automatically corrected if the trial mounting of the component is performed once before the mounting of the component on the board is started, the component mounted by the operator as in the conventional case is mounted. It is not necessary to measure the amount of deviation of the coordinate data to correct the coordinate data, no expert is required for the trial mounting work, and the working time can be greatly shortened.

Further, since a person does not measure the displacement amount, the position accuracy is improved. The correction of the coordinate data described above may be performed when the pattern of the substrate may change, for example, when the lot of the substrate is changed.

When mounting the components on the individual substrates, it is possible to eliminate the displacement of the mounting position of the components by photographing the substrate pattern of each component with a camera and performing the image recognition processing. However, since the image recognition processing takes time, if the image recognition processing is performed for each component, the mounting speed of the component becomes slow. In the present embodiment, the above-described correction is performed before starting the mass production of the substrates, so that the required positional accuracy is satisfied and the components can be mounted at high speed.

In the above embodiment, the board pattern is photographed by the camera, the coordinate data is corrected by the amount of deviation of the board pattern, and then the component is mounted on the board. After mounting the component based on the mounting position coordinate data of the, the difference data between the coordinate data of the pad taken by the board shooting camera and the actual coordinate data of the component mounted on the board is calculated, and only the difference data is coordinated. The data may be corrected.

The coordinate data correction method of the present invention is not limited to the electronic component mounting apparatus described in the embodiments, but can be applied to electronic component mounting apparatuses having various configurations as long as it has a board photographing camera. .

[0031]

According to the present invention, the correction of the coordinate data before the mounting of the component on the board is performed only once, the working time is shortened, and the deviation amount of the mounted component is measured. Since it is not necessary to modify the position data by using it, even an unskilled person can prepare before starting production. Furthermore, since the coordinate data is corrected based on the position coordinates of the mounted component obtained by image recognition instead of the method of measuring the displacement of the mounted component by trial mounting by a human, the mounting position accuracy of the component can be further improved.

[Brief description of drawings]

FIG. 1 is a flowchart showing a coordinate data correction method according to an embodiment.

2A is a diagram showing a photographed image of a board pattern, and FIG. 2B is a diagram showing a photographed image of a mounted component.

FIG. 3 is a flowchart illustrating a conventional coordinate data correction method.

Claims (1)

[Claims] 1. A step of sequentially recognizing an image of a board pattern corresponding to a preset component mounting position to calculate coordinate data of the board pattern, and an image recognizing an electronic component mounted on the board to perform the electronic component. A step of calculating coordinate data of the component, a step of calculating difference data between the coordinate data of the board pattern and the coordinate data of the mounted component, and a step of correcting the mounting position coordinate data of the component based on the difference data. A coordinate data correction method for an electronic component mounting device, comprising: