US 5,347,462 A · Method for machining printed circuit board

Abstract

In order to enable the determination of a center precisely and automatically, a reference mark on a printed circuit board is image-recognized to determine tone transition points, thereby to determine an interim center and diameter of the mark by a four-points searching method. Next, a preset minute value .alpha. is added to the interim mark diameter to determine a standard circle diameter, thereby to set a standard circle having the interim center as its center. Then, image processing is performed in that standard circle and the mark is separated into a plurality of sections. The center of the mark is detected by determining the center of the section of the tone indicating the mark. Machining operations such as the perforations are carried out on the basis of the detected center.

Claims10

Dependent claims

A method of machining a printed circuit board, comprising the steps of:

detecting the position of a reference mark formed in advance on the printed circuit board, with imaging means and an image processing device, said step of detecting the position of the reference mark comprising the steps of:
image-recognizing said mark to detect a tone transition point on X and Y axes;
determining an interim center and diameter of said image-recognized mark on the basis of said tone transition point;
adding a predetermined minute value to said image-recognized mark diameter to compute a value of the diameter of a standard circle;
setting said standard circle to have the computed value as its diameter and said interim center as its center;
and
image-processing in said standard circle to determine the center of said mark;
and
machining said printed circuit board with machining means with reference to said detected mark position.

6 more elements

An apparatus for processing a mark on a printed circuit board, wherein the board has a mark thereon with a first distinguishing tone and the board surrounding the mark has a second distinguishing tone, comprising:

means for producing an image of said mark,
means for:
intersecting the image with first and second orthogonal axes,
determining first and second coordinates on each of said first and second axes, respectively, corresponding to intersection points of said axes with a periphery of said image,
determining an interim center from said first and second coordinates,
averaging the distances between the intersection points on said first and second axes to determine a mark diameter,
adding a predetermined value to said mark diameter to provide a standard diameter,
centering a circle with said standard diameter at said interim center,
separating said circle into a plurality of areas with equidistantly spaced lines extending parallel to said first and second axes,
determining a tone for each of said areas as a function of the ratio of said first and second tones therein,
determining the coordinates of a final center with respect to which an equal number of areas of said first tone occur in directions parallel to said first and second axes, and
means for machining said board at a point corresponding to said final center of said image.

9 more elements

Dependencies are inferred from the claim text.

Method for machining printed circuit board

Life of this patent

Method for machining printed circuit board

Life of this patent

Abstract

Claims10