JPH0240442B2 - KIBANNOKIJUNANAKAKOHOHO - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a method for drilling reference holes in a substrate.

(B) Prior Art When a plurality of printed wirings are provided on a single board, a reference mark is provided for each wiring. The number of reference marks varies depending on the size of each printed wiring, but is usually from several tens to over a hundred. A hole that will serve as a reference will be drilled at this reference mark position in a subsequent process. Therefore, it is necessary to detect the positions of a large number of reference marks on a single board and drill holes, but conventionally, for example, an eddy current type position sensor is used to detect the coordinates of all reference marks and drill holes. Was.

(C) Problems to be Solved by the Invention However, with the method described above in which the coordinates of all reference marks are detected by a position sensor and holes are drilled at the coordinate positions, it is difficult to determine the position because there are a large number of reference marks. There is a problem that detection takes a very long time and the entire processing time increases. For example, assuming that it takes 2 seconds to detect a position and 1.5 seconds to drill a hole, if there are n reference marks, it would take 3.5×n seconds for one board. The present invention aims to solve these problems.

(d) Means for solving the problem The present invention actually detects the coordinates of only three reference marks, and calculates the coordinates of the remaining reference marks based on the detection results of the three reference marks. This solves the above problems. That is, the method for drilling reference holes in a substrate according to the present invention is as follows:
For the first board, all the reference mark positions are detected and drilled, and their coordinates are memorized, and for the second and subsequent boards, only the three desired reference mark positions are detected and these 3
The coordinate conversion coefficients are calculated from the coordinate detection values of the two reference mark positions and the coordinate memory values of the three corresponding reference mark positions on the first sheet, and for the reference mark positions other than the three above, the coordinates of the first sheet are calculated. The method is characterized in that coordinates are determined by performing calculations on stored values based on coefficients of coordinate transformation, and drilling is performed at the reference mark positions thus obtained.

(E) Effect The fiducial marks are printed on the substrate, and the relative positional relationship of each fiducial mark hardly changes for each substrate other than being slightly enlarged or reduced as a whole. However, the reference mark as a whole moves parallel to or rotates with respect to, for example, an end face of the substrate that serves as a reference, causing variations for each substrate. By detecting the coordinates of all the reference mark positions on the first substrate, the relative positional relationship of each reference mark can be determined. Next, the coordinates of the three reference marks on the second board are detected and compared with the corresponding coordinates of the three reference marks on the first board.
It can be seen how much the reference mark on the second board is displaced (enlargement/reduction, parallel movement, and rotation) with respect to the reference mark on the first board. Therefore, by performing calculations on the coordinates of each reference mark on the first substrate in accordance with the above displacement, the coordinates of each reference mark on the second substrate can be calculated. Drilling may be performed at the coordinates thus calculated. Since coordinate detection only requires three reference marks, the time required for detection is, for example, in the above example.
The time will be shortened by (n-3)×2 seconds. For the third and subsequent boards, it is sufficient to detect reference marks at only three locations in the same manner.

(F) Embodiments Examples of the present invention will be described below with reference to FIGS. 1 to 5 of the accompanying drawings.

FIGS. 1 and 2 show a substrate reference hole machining apparatus for carrying out the method of the present invention. A drill head 14 equipped with an eddy current position sensor 10 and a drill 12 is attached to a table 18 movable in the X direction by a servo motor 16, and this table 18 is further moved in the X direction by a servo motor 20.
Table 22 movable in the Y direction perpendicular to the direction
is placed above. The operation of the servo motor 16 and the servo motor 20 is controlled by a controller 24, and the operation of the servo motor 16 and the servo motor 20 is controlled by a controller 24.
Signals corresponding to the rotational position of the drill head 14, that is, the coordinates of the drill head 14 in the X and Y directions, are detected by, for example, a pulse detector provided thereon, and are input to the controller 24. A detection signal from the eddy current position sensor 10 is also input to the controller 24 .

Next, a reference hole machining method using this device will be explained.

First, a method of detecting and processing one reference mark 32 (copper mark) will be described. The eddy current type position sensor 10 is positioned approximately above the reference mark 32 of the substrate 30 as shown in FIG. 3 (point A in FIG. 3),
Next, the servo motor 16 is activated to cause the eddy current position sensor 10 to reciprocate in the X direction as shown by the broken line in FIG. When moving to the right in FIG. 3 through point B, the output current detected by the eddy current position sensor 10 changes as shown in FIG. 4. The coordinate b indicated by the pulse signal from the servo motor 16 at the point where the current rises to a predetermined value (that is, this corresponds to point B) is stored in the controller 24. Further, the output current of the eddy current position sensor 10 when moving to the left in FIG. 3 through point C also changes as shown in FIG. 5, and the coordinate value c at point C is stored. The controller 24 performs the calculation x=(b+c)/2,
This x indicates the coordinate of the center position of the reference mark 32 in the X direction. This X-direction coordinate is also stored in the controller 24. Next, the servo motor 20 is operated to reciprocate the eddy current position sensor 10 in the Y direction, and the center position of the reference mark 32 in the Y direction is calculated by the same operation as described above. This coordinate in the Y direction is also stored. This means that the center position of the reference mark 32 has been detected. Next, the servo motor 16 and the servo motor 20 are operated to move the drill 12 to this center position. That is, from the state where the eddy current position sensor 10 is aligned with the center position of the detected reference mark 32, the servo motor 16 is operated to move the drill head 14 by the distance l between the eddy current position sensor 10 and the drill 12. The state will be as follows. Thereby, the drill 12 is aligned with the center position of the reference mark 32. Next, the drill 12 is lowered and the reference hole is machined. As a result, reference mark 3
A reference hole is accurately drilled in the center of 2.

Next, a method of machining a large number of reference holes according to the present invention will be explained. For example, as shown in FIG. 6, the board 30 is provided with a large number of reference marks 32 in a grid pattern.
For the second one, coordinates are detected and holes are processed for all reference marks 32 using the method described above, and all detected coordinates are transferred to the controller 24.
Store it in the internal memory.

Next, for the second board 32, for example
The coordinates are actually detected only for the three reference marks 32, A', B', and C'. The coordinates of these three reference marks 32 are (P _X1 , P _Y1 ), (P _X2 ,
P _Y2 ), and (P _X3 , P _Y3 ). In addition, A of the three corresponding reference marks 32 on the first board 30,
The stored coordinates of B and C are respectively (Q _X1 ,
Q _Y1 ), (Q _X2 , Q _Y2 ), and (Q _X3 , Q _Y3 ).

Generally, a coordinate transformation between two two-dimensional coordinate systems can be represented by a 3×3 transformation matrix as shown below.

_{K 11 K 21 0 K 12} K _{22 0 T}
coefficients related to contraction), shear, and rotation;
Furthermore, T _X and T _Y are coefficients related to parallel movement.
Note that the third row was added to create a 3x3 matrix and does not affect the coordinate transformation (strictly speaking, the first and second columns (0, 0) are related to projection, and the Column 3 (1) is related to overall scaling, but selecting this value results in a simple coordinate transformation). _Therefore , _{the relationship between} (P _{X ,} P _Y ) and ( _{Q X} , _{Q Y ) is P} 1). From the correspondence of the coordinates of the above three points, From this we can get K ₁₁ , K ₁₂ , K ₂₁ ,
The values of K ₂₂ , T _X , and T _Y can be determined. Therefore, (P _X , P _Y ) corresponding to any (Q _X , Q _Y ) is
It can be calculated from equation (1). This calculation is performed by the controller 24, and the drill 12 sequentially moves to the calculated coordinate positions to perform drilling.
Therefore, detection work is not necessary for the reference marks 32 other than the three whose positions have actually been detected, and the work time is shortened. Although the present invention is applicable to a substrate having four or more reference marks 32 on one substrate, this effect becomes greater as the number of reference marks 32 increases.

(g) Effects of the invention As explained above, according to the present invention, 3
Since only one fiducial mark position is actually detected and the remaining fiducial mark positions are calculated, the time required to drill fiducial holes on a board with many fiducial marks can be significantly reduced. .

[Brief explanation of drawings]

Fig. 1 is a plan view showing the reference hole machining device used to carry out the method of the present invention, Fig. 2 is a view seen in the direction of the arrow in Fig. 1, and Fig. 3 is the locus of the reference mark and the eddy current position sensor. FIG. 4 and FIG. 5 are both diagrams showing changes in the output current of the eddy current type position sensor, and FIG. 6 is a diagram showing the substrate. 10... Eddy current position sensor, 12... Drill, 30... Board, 32... Reference mark.

Claims (1)

[Claims] 1. In a method for drilling reference holes in a board, in which holes are drilled at the positions of four or more reference marks provided on a board, the positions of all the reference marks are detected and the holes are drilled for the first one board. At the same time, those coordinates are memorized, and for the second and subsequent boards, only the desired three reference mark positions are detected, and the detected coordinate values of these three reference mark positions are compared with the three corresponding ones of the first board. The coordinate conversion coefficients are calculated from the coordinate memory values of the reference mark positions, and for reference mark positions other than the three mentioned above, calculations are performed on the coordinate memory values of the first sheet based on the coordinate conversion coefficients. A method for drilling a reference hole in a board, the method comprising determining coordinates and drilling a hole at the reference mark position obtained in this manner.