JPH0772931A - Parts positioning method - Google Patents

Abstract

PURPOSE:To eliminate a dislocation defect due to erroneous detection by accurately judging the erroneous detection of the desired coordinate position of a positioning object as an error when it is performed. CONSTITUTION:When electronic parts are packaged by positioning on a substrate, the coordinate positions of diagonal two points A, B on the substrate and that of the diagonal two points C, D of the electronic parts in accordance with them are detected, and inclination correction quantity theta between each diagonal two points is calculated, and inclination can be corrected (101-104). After that, dislocation mean values in directions of X, Y between the diagonal two points A, C on one side of the substrate and the electronic parts and the diagonal two points B, D on the other side are found, and position correction in the directions of X, Y can be performed as the correction quantity (105-107). Position displocation quantity between each diagonal two points of the substrate and the electronic parts can be calculated similarly by the coordinate positions of the points A, B, C, and D after correction, and it is checked whether or not they show values less than an allowable value, then, the accuracy of positioning can be decided (108, 109).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a component positioning method in a working machine or the like for positioning and mounting electronic components on a substrate.

[0002]

2. Description of the Related Art Conventionally, in a working machine that requires alignment when mounting electronic parts on a board, for example, as described in Japanese Patent Application Laid-Open No. 59-2334, a pair of a board and an electronic part is paired. After placing the two corners on the same virtual coordinate and adjusting the inclination of the two diagonals to one of the two, the midpoints of the two diagonals of the board and the electronic component are calculated, and the midpoint between the midpoints is calculated. X direction, Y
The positional shift in the direction was calculated, and this positional shift was used as the correction amount when positioning the board and the electronic component.

The contents of the above conventional technique will be described in detail with reference to FIG. In FIG. 3, 1 white dot is the electrode pattern of the substrate and 2 black dots are the electrode pattern of the electronic component. Further, the tilt correction (θ correction) is performed by rotating the electronic component, and the position correction (XY correction) is performed by moving the substrate.

(1) Coordinate positions (Ax, Ay), (Bx, By) of two diagonal points A and B in the electrode pattern 1 of the substrate, and two diagonal points C in the electrode pattern 2 of the electronic component. , D coordinate positions (Cx, Cy) and (Dx, Dy) are detected.

(2) Inclination θk of the substrate from the coordinate values of A and B
Is calculated by θ _k = tan ⁻¹ {(Ax−Bx) / (Ay−By)} (1), and similarly, the inclination θc of the electronic component is calculated from the coordinate values of C and D, and θ _c = tan ⁻¹ {(Cx-Cy) / (Cy-Dy)} (2) Then, the tilt correction amount (θ correction amount) θ is calculated by θ = θk−θc (3), and the electronic component is rotated by θ around the origin of the coordinates to match the tilt of the substrate (θ correction).

(3) After the above θ correction, the coordinate positions (Cx, Cy) and (Dx, Dy) of two diagonal points C and D of the electronic component are again obtained.
To detect. Coordinate positions of two diagonal points A and B (Ax,
Ay) and (Bx, By) remain unchanged.

(4) The X direction between the center of the two diagonal points A and B of the board and the midpoint of the two diagonal points C and D of the electronic component after θ correction,
The positional displacement amounts X and Y in the Y direction are expressed as follows: X = {(Ax + Bx) / 2}-{(Cx + Dx) / 2} (4) X = {(Ay + By) / 2}-{(Cy + Dy) / 2} (5 ), The substrate is moved by the X and Y (XY correction).

(5) After XY correction, the coordinate positions (Ax, Ay) and (Bx, By) of the two diagonal points A and B on the substrate are detected again. The coordinate positions (Cx, Cy) and (Dx, Dy) of the two diagonal points C and D of the electronic component after θ correction have been detected in (3).

(6) A, B, C, D after the above XYθ correction
The inclination amount θ and the positional displacement amounts X and Y are calculated again by the equations (1) and (5) using the coordinate values of | θ | ≦ Δθ, | X |
Check whether ≦ ΔX and | Y | ≦ ΔY are all satisfied (positioning consistency check). Note that Δθ, ΔX, Δ
Y is each matching degree allowable value. Then, if all of θ, X, and Y are equal to or less than the allowable values, the component is mounted on the board.

[0010]

According to the above-mentioned prior art, when the positions of the electrode patterns A to D of the substrate and the electronic component are detected without being mistaken as different positions, the positioning can be performed without any problem. If the pitch shift is detected, no error is found in the conformity check, and there is a problem that the electronic component is mounted with a shift. This will be described with reference to FIG.
Note that, in FIG. 4, in order to make the positional relationship between the substrate and the electronic component easy to understand, the electronic component side is operated in three directions of XYθ.

First, before correction, the electrode pattern 1 of the substrate and the electrode pattern 2 of the electronic component are in the state shown in FIG. 4A, and the positions of points A, B ', C and D are detected. To do. However, B'is an erroneous detection position, which is originally one pitch lower than B.
It is to detect points. Next, the above equation (1),
The correction amount of θ is calculated in (2) and (3), and the electronic component is rotated by θ. The state after θ correction is shown in (2) of FIG. Here, the original must be combined θ ₀ to θ _k, in order to become combined θ _c to 'θ _k to have been erroneously detected as' the B B, the slope of the CD and AB' is, suits However, the overall shape is shifted by Δθ (θk = θ _k −θ _k ′).

Finally, the correction amount in the XY directions is expressed by the equation (4),
The calculation is performed in (5), and the electronic component is moved. The state after this XY correction is shown in FIG. As a result, the midpoint E of AB '
And the midpoint F of the CD coincide with each other, but in the end, B is erroneously detected as B ′, so that the correction is performed by shifting the whole amount by Δθ.
Further, if the check whether or not the positioning is accurately performed is detected again after the corrections A, B ', C and D, the inclinations θ of AB' and CD match, and the midpoints also match. Therefore, it is not judged as an error and the electronic component is removed and mounted.

It is an object of the present invention to provide a component positioning method capable of performing accurate positioning without deciding that an error has occurred and not mounting the component when the above-mentioned erroneous detection is made.

[0014]

In order to achieve the above object, the present invention provides an outermost one of a first component such as a substrate and a second component such as an electronic component after tilt correction (θ correction). Diagonal 2
Positional deviations in the X and Y directions between the points A and C and the other two outermost diagonal points B and D are calculated, and the average value of the positional deviations in the X and Y directions is corrected. Is characterized by performing alignment in the XY directions.

Also, when checking the matching of the positioning after the θXY correction, similarly, two diagonal points A and C on one side of the first component and the second component and a diagonal angle 2 on the other side of the second component. It is characterized in that the positional deviation amount in each of the X and Y directions between the points B and D is obtained, and whether or not each positional deviation amount is equal to or less than an allowable value is checked to determine the positioning accuracy.

[0016]

When the erroneous detection of the coordinate position is detected by paying attention to the shift amount between the two outermost diagonal points of the first component such as the substrate and the second component such as the electronic component, the conventional What could not be identified by the amount of deviation between the midpoints can always be identified as an error, and accurate positioning becomes possible.

[0017]

An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a schematic configuration of an apparatus for positioning and mounting electronic components on a board. In the figure, the electronic component 11 is attracted to the tip of the bonding head 10,
A substrate 13 is placed on the table 12. The electrode pattern of the electronic component 11 passes through the prism 14 and the mirror 15 and is detected by the detector 16. The electrode pattern on the substrate 13 passes through the prism 14 and the mirror 17, and is detected by the detector 18. The control unit 19 inputs the electronic components 11 and the electrode patterns of the substrate 13 detected by the detectors 16 and 18, first calculates the θ correction amount, and rotates the bonding head 10 around the Z axis to rotate the electronic components. 11 θ correction, then X
The position shift amount in the Y direction is calculated, the XY table 12 is moved in the X and Y directions, and the XY correction of the substrate 13 is performed. After this θXY correction, the control unit 19 inputs the electrode patterns of the electronic component 11 and the substrate 13 again and calculates the θXY correction amount. Is mounted on the substrate 13 and the mounting operation is started.

FIG. 2 shows a processing flowchart of the control unit 19 of FIG. Hereinafter, an embodiment of the component positioning method according to the present invention will be described with reference to FIG.
As described with reference to FIG. 4, the electrode pattern 2 of the electronic component is aligned with the electrode pattern 1 of the substrate. At this time,
The position of B on the electrode pattern 1 of the substrate is set to B ′ one pitch above.
The case where the position is erroneously detected will be described.

(1) The coordinate positions of two diagonal points A and B in the electrode pattern 1 on the substrate are detected (step 101). However, in FIG. 4, it is assumed that the position of B erroneously detects the position of B'one pitch higher.

(2) The coordinate positions of two diagonal points C and D in the electrode pattern 2 of the electronic component are detected (step 102).

[0022] (3) A, B 'from the coordinate values of (originally B), the inclination theta _k substrate by the preceding formula (1)' (originally theta _k)
Then, from the coordinate values of C and D, the inclination θ _c of the electronic component is calculated by the above equation (2), and the inclination correction amount θ is calculated by the equation (3).

(4) The electronic component is rotated by θ about the Z axis of the XYZ coordinates to match the inclination θ _k ′ (original θ _k ) of the substrate (step 104). This (θ) is shown in (1) of FIG.
The state after correction is shown. Since B is erroneously detected as B ′ and θ correction is performed, θ correction is performed in a form shifted by Δθ (Δθ = θ _k −θ _k ′).

(5) The coordinate positions of two diagonal points C and D in the electrode pattern 2 of the electronic component after θ correction are detected (step 105).

(6) A, B '(original B) after θ correction,
From the coordinate values of C and D, the positional displacement amounts X and Y in the X and Y directions between the board and the electronic component are calculated by the equations (6) and (7) (step 106).

X = (x ₁ + x ₂ ) / 2 (6) Y = (y ₁ + y ₂ ) / 2 (7) That is, as shown in (1) of FIG. The displacement amounts x ₁ and y ₁ in the XY directions of the two outermost diagonal points A and C of the electrode pattern 2 are calculated, and similarly,
The amount of deviation x between the other two outermost diagonal points B '(originally B) and D
Calculate ₂ and y ₂ . Then, the average value of the deviation amounts in the X and Y directions between the two diagonal points is set as the XY correction amount.

(7) The position correction in the XY directions is performed based on the XY correction amount obtained in step 106 (step 10
7). FIG. 5B shows the state after XY correction. Note that, in (2) of FIG. 5, in order to make it easier to understand the positional relationship between the substrate and the electronic component, the electronic component side is moved to perform the XY correction, but in the configuration of FIG. The correction is performed by moving the substrate side.

(8) Electrode pattern 1 on the substrate after XY correction
The coordinate positions of the two diagonal points A and B '(originally B) are detected (step 108). When the electronic component is also moved for the XY correction, the coordinate positions of the two diagonal points C and D of the electronic component are naturally detected.

(9) The θXY positioning matching is checked using the coordinate values of A, B '(original B), C, D after θXY correction (step 109).

In this case, the amount of inclination θ is expressed by the above equations (1) to
It is calculated by (3), and it is checked whether it is less than or equal to the allowable value. However, as shown in (2) of FIG. 5, the displacement in the XY directions is two diagonal points A and C between the substrate and the electronic component. , B ′ (original B) and D in the X and Y directions, x ₁ ′, y ₂ ′,
x ₂ ′ and y ₂ ′ are respectively obtained, and whether or not these four amounts are each less than or equal to the allowable value is checked to determine coincidence. As a result, conventionally, only the amount of deviation near the midpoint was known, and therefore, if the entire deviation occurred, it could not be detected as a failure (NG), but in the present embodiment, the outermost part of the electrode pattern of the substrate and the electronic component was detected. By calculating the amount of displacement of the two diagonal points in the XY directions, various abnormalities can be dealt with.

(10) If all the deviation amounts in the θXY directions are equal to or less than the allowable value, the electronic component is mounted and mounted on the substrate (step 110), and if the allowable value is not satisfied, error processing is performed (step 111). .

The case of mounting electronic components on a substrate has been described above as an embodiment of the present invention. However, the present invention is not limited to this, and is generally applicable to a case where alignment between components is generally required. Needless to say.

[0033]

As is apparent from the above description, according to the present invention, it is possible to eliminate the positional deviation defect due to the erroneous detection of the desired coordinate position on the positioning object, and it is possible to perform the accurate positioning.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of a positioning device to which the present invention is applied.

FIG. 2 is a processing flowchart for explaining an embodiment of the method of the present invention.

FIG. 3 is a diagram showing a relationship between a board and a pattern of an electronic component.

FIG. 4 is a diagram showing a specific example for explaining a conventional positioning method.

FIG. 5 is a diagram showing a specific example for explaining the positioning method of the present invention.

[Explanation of symbols]

 10 Bonding Head 11 Electronic Component 12 XY Table 13 Substrate 16, 18 Detector 19 Control Section

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location // G05B 19/18

Claims (2)

[Claims] 1. An automatic positioning method between parts, comprising detecting the coordinate positions of two diagonal points A and B on the first part and two diagonal points C and D on the second part. After matching the inclinations of two diagonal points on one side with the inclinations of two diagonal points on the other side, two diagonal points A and C on one side of the first part and the second part and a diagonal side on the other side Two
It is characterized in that the amount of positional deviation in each of the X and Y directions between the points B and D is obtained, and the alignment in the XY direction is performed using the average value of the amount of positional deviation in each of the X and Y directions as a correction amount. Parts positioning method. 2. The component positioning method according to claim 1, wherein after the alignment in the XY directions, two diagonal points A and C on one side of the first and second components and a diagonal point on the other side. It is characterized in that the amount of positional deviation between each of the two points B and D in the X and Y directions is obtained, and whether or not each amount of positional deviation is below an allowable value is checked to determine the accuracy of the positional amount determination. Parts positioning method.