Step-by-step feed system for photocopying apparatus

Claim 1

A STEP-BY-STEP FEED MECHANISM FOR PHOTOCOPYING APPARATUS ADAPTED TO OPERATE WITH COPYING MATERIAL IN STRIP FORM, COMPRISING AN ADJUSTABLE LENGTH MASKING DEVICE DEFINING A CORRESPONDINGLY ADJUSTABLE LENGTH PICTURE APERTURE, ROLLER GUIDE MEANS FOR GUIDING A STRIP OF COPYING MATERIAL IN A PLANE PARALLEL TO THE PLANE OF SAID MASKING DEVICE ADJACENT SAID PICTURE APERTURE AND LONGITUDINALLY THEREOF, SAID MASKING DEVICE INCLUDING FIRST AND SECOND PARALLEL SPACED PARTS LYING TRANSVERSELY OF THE DIRECTION OF TRAVEL OF THE COPYING MATERIAL WHICH ESTABLISH THE UPPER AND LOWER SIDES OF SAID PICTURE APERTURE, SAID FIRST AND SECOND PARTS BEING ADJUSTABLE PARALLEL TO THEMSELVES TOWARDS AND AWAY FROM EACH OTHER TO CORRESPONDINGLY SHORTEN OR LENGTHEN SAID PICTURE APERTURE IN ACCORDANCE WITH THE REQUIREMENTS OF A PICTURE FORMAT, A MARKING DEVICE INCLUDING MEANS FOR MAKING A MARK ON THE COPYING MATERIAL BEFORE THE MATERIAL ENTERS SAID PICTURE APERTURE, SAID MARKING DEVICE AND SAID FIRST PART OF SAID MASKING DEVICE BEING COUPLED TOGETHER FOR MOVEMENT AS A UNIT AS SAID FIRST PART IS ADJUSTED, A SENSING DEVICE INCLUDING MEANS FOR DETECTING MARKS MADE ON THE COPY MATERIAL BY SAID