Pin register system for screen printers

Abstract

A registration apparatus and method is provided to accurately register film positive on screens held by screen frames and to likewise accurately register the screen frames within a printing apparatus with a registration system which reduces set-up time required for the printing machine without requiring an expensive automated registration system. An image positive is positioned on a vacuum table relative to a pair of registration pins or members which fit registration clamps on the screen frame. A plurality of pin tabs are secured on the vacuum table with their respective pins projecting through holes in the image positive. Each successive positive will be positioned on these pin tabs so that all successive positive have the same relationship between their respective image and the registration clamps of their associated screen frames. A calibration pallet is sequentially mounted on successive rotatable pallet arms and carries front and rear alignment holes already aligned with holes in alignment brackets on the front and rear portions of the screen holder. Pins are inserted through holes in the respective alignment brackets on the screen holder and holes in the calibration pallet at each of the respective printing stations. The alignment brackets on the screen holders are fixed in position, and the alignment pins are removed. With this alignment, the screen frames are each fastened in position at their respective screen holders by passing pins through the alignment brackets of the screen holder, through holes in the screen frame registration clamps, and into alignment holes of the calibration pallet to accurately align each of the screens relative to one another.