METHOD OF AND DEVICE FOR MAKING BASE HOLES IN FILM MASKS OF PRINTED-CIRCUIT BOARDS Russian patent published in 1994 - IPC

FIELD: manufacture of printed-circuit boards. SUBSTANCE: before punching base holes maximum deviation of centers of images of mask contact pads from respective components of map graticule is measured, this procedure being followed by displacement of mask through half the measured value towards its decrease. Device for implementing this method has base 1 with punching unit having dies 2, detachable guide frame 3, and punches 4. Base mounts screen built up of transparent plates 5 and 6 with vacuum chamber 7 formed between them. Plate 5 has holes 9 and map graticule is applied to it. EFFECT: improved accuracy of location of base holes. 7 dwg