GB1161618A - Improvements in and relating to a Sheet Retarding Device on a Printing Machine - Google Patents

Abstract

1,161,618. Sheet retarding device. SOC. DES FORGES ET ATELIERS DU CREUSOT. 23 June, 1967 [28 June, 1966], No. 29128/67. Heading B8R. A retarding device for a printing machine prior to delivery comprises a rotary cylinder having rectractable means engaging the forward part of a sheet, and at least one retarding element which rotates in the opposite direction and projects periodically outside the cylinder periphery in a predetermined angular position to engage the trailing part of the sheet between this retarding element and a co-operating roller. Fig. 1 illustrates a cylinder 1 having retractable spikes 2 which engage the forward part of sheet sections 3; two retarding elements comprising bars 4 on axes 5 which are parallel to the cylinder axis 6 are mounted diametrically opposite each other to rotate in the opposite direction to cylinder 1 by means of a fixed gear 8 planer gears 7 and gears 9 carried on axes 5. Each bar 4 has a rounded outline 4a which projects beyond the cylinder periphery through openings 1a, each bar 4, for example, rotating twice for every revolution of cylinder 1. A roller 10 co-operates with the bar 4 when in the correct angular position, Fig. 2 (not shown), a resilient push-rod 11 engaging the trailing part of sheet 3 against bar 4; the speed of rotation of roller 10 is matched to that of bar 4, so that together they exert a retarding action on the sheet when spikes 2 are retracted, Fig. 3 (not shown). The cylinder 1 can contain a number of these spikes and bars, and more than one co-operating roller 10 may be contemplated by the invention.