Information retrieval from punched cards designed for manual use or handling by machine (G06K19/00 takes precedence; detection or correction of errors by rescanning patterns G06V10/98; checking correct operation of card-conveying mechanisms G06K13/06); Apparatus for handling such cards, e.g. marking or correcting

Child Classifications

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• G06K 21/002
• G06K 21/02 in which coincidence of markings is sensed mechanically, e.g. by needle
• G06K 21/04 in which coincidence of markings is sensed optically, e.g. peek-a-boo system
• G06K 21/06 Apparatus or tools adapted for slotting or otherwise marking information-retrieval cards
• G06K 21/08 Apparatus or tools for correcting punching or slotting errors