GB1103293A - Improvements in or relating to sheet feeding apparatus - Google Patents

Abstract

1,103,293. Feeding sheets. HARRIS-INTERTYPE CORPORATION. 25 June, 1965 [1 July, 1964], No. 27127/65. Heading B6B. Sheets are fed sequentially from the top of a pile 28 on to a table 20, and conveyed along the table in underlapped fashion by pairs of grippers 38 on endless chains 35 to engage rising and falling register stops 45, and are then fed to the grippers 15 of the cylinder 10 of a printing press by suction belts 55 which accelerate the sheets to engage stops on the cylinder. Since a sheet being registered by the stops 45 is covered by the trailing portion of the preceding sheet fed by the grippers 15 of the cylinder, disturbance of the registered sheet is prevented by hook portions 48 on the stops 45, Figs. 2 and 3 (not shown). When the sheets are front-registered, a known side register mechanism 25 becomes operative. Arms 22 on a cross-shaft serve to guide the sheets towards the cylinder 10. The suction conveyer means comprises a box-like member 50, Figs. 2-7 (not shown), extending along an aperture in the table 20 between the side register support plate 24 and the stops 45, which is connected by pipe 100 to a three-way valve 102. The valve 102 is operated automatically to connect, alternately, the box 50 to sources of vacuum and compressed air, or to neither. In one form (Figs. 1-9), the box 50 is covered by non- continuous perforated belts 55 which have one end fastened to a roller 60 and the other to a take-up roller 65, and they are guided over the box 50 by a roller 61. The belts are fed in the direction of sheet feed from rest up to the speed of the grippers 15 of the cylinder 10, and then in the reverse direction, by a cam-operated arm 80 having a toothed rack 78 which drives gearing 72-76 connected to the shaft 68 on which the roller 86 is secured. The shaft 68 is connected by gearing to the shaft 88 of the roller 65 through a lost-motion clutch (Fig. 8), which compensates for the overlapping of the belts 55 on the rollers 60, 65. In a modification, Figs. 10 and 11 (not shown), the suction belts 55 are replaced by endless belts 105, and include arrangements, such as a pin-feed or timing belts for ensuring correct belt feed. These belts can be driven unidirectionally through a one-way clutch, or can be driven first in one direction, and then in the reverse direction. The periods when compressed air is established at the box 50 and perforated belts 55 or 105 causes quick release of the sheets by the belts, and tends to float the sheet over the belts when the grippers 15 are operative on the sheets.