Improvements in or relating to delivery devices for rotary printing machines and high speed printing presses

摘要

769,979. Sheet-delivery apparatus. MASCHINENFABRIK AUGSBURG - NURNBERG AKT.-GES. May 13, 1955 [May 22, 1954], No. 13928/55. Class 100(1) In a sheet-delivery device for rotary printing machines suction applied for retarding the delivery of individual sheets is varied in dependance on the speed of the printing machine. Sheets delivered by a conveyer 2 on to a stack 3 pass over a retarding roller 4 by which suction is applied to the end of a sheet passing over the roller, the timing of the suction being controlled by valve 6. In a vacuum pipe leading from the valve 6 to an independently driven suction source 5 is a throttle 7 which is controlled by a centrifugal governor 8 connected to the drive of the printing machine. Thus, as the speed of the machine increases the throttle 7 allows a greater amount of suction to be applied to the sheets. In an alternative embodiment the throttle 7 is located in a branch pipe leading from the main vacuum pipe to the atmosphere (Fig. 2, not shown).