Patent GB-181913-A (GB)
Title: Improvements in printing presses
IPC: B41F1/28
Filed: 1921-04-29
Abstract: 181,913. Grosse, E. April 29, 1921. Platen machines; inking- apparatus.-In a platen printing-press of the kind in which the inking-rollers are carried by endless chains, bands, &c. passing round the forme bed, the sheets are delivered from the platen by grippers or other stripping-devices carried by the chains &c. in advance of the inking-rollers and adapted to carry the sheets upwardly out of the press. The stripping-devices may deposit the sheets directly upon the delivery board or may transfer them to intermediate delivery grippers or delivery bands. In one form, Figs. 1 and 2, endless chains 10 carrying the inking-rollers 12, 13, 14 support carriages 15 in which is mounted a shaft 29, to which are secured arms 28 carrying spring-closed delivery grippers 27, and an arm 30 carrying a roller adapted to coact with an adjustable cam 34 on the frame. A gear-wheel 57 loose on the shaft 29 meshes with a gear 56 to which is fixed an eight-toothed star-wheel 55. The arm 28 is normally held by a spring against a stop on the gear 57 and a brake device is provided to prevent the movement of the arm 28 against the spring action from turning the gears 57, 56. As the chains 10 rotate in the direction of the arrow in Fig. 2, the cam 34 moves the arm 28 towards the platen 7, and a pin 38 on the cam 34 acts upon an arm 39 of one of the gripperjaws 27 to open it to receive the sheet 40, which is then carried upwards to the delivery board 54, Fig. 1. Eight stops 59, arranged in the path of the star-wheel 55, act to turn the arm 28 step by step and a stop 66 is provided to open the grippers at the delivery point. Instead of the gears 57, 56, a disc 67, Fig. 3, having pins 70 engaging the star-wheel 71, may be fixed to the shaft 29 and the cam 34 may have two projections 73, 75 which act upon the wheel 71 to throw the arm 28 toward and from the platen. When the arm 28 moves towards the platen, the gripper is opened by a projection 72 on the carriage 15. During the delivery of the sheet, the wheel 71 is turned step by step by the stops 59 as before. When tissue or other flimsy sheets are printed, their upward movement off the platen is assisted by rubber tipped fingers 44 pivoted in a carriage 42, secured to the chains 10 and having weighted or spring-pressed arms 46 linked together. A spring-pressed lever 48 having a tooth 49, engaging a notched sector 51 on the pivot of one of the fingers 44, holds the fingers inoperative until it strikes an adjustable stop 52 on the platen, thereby allowing the fingers to engage the sheet and slide it upwardly along the platen. In another form of machine, the sheets are taken from the grippers 27 by other grippers on an oscillating arm operated by rack and pinion gear, and deposited upon a delivery table arranged above the chains 10. In a further form, the grippers 27 are replaced by a hooked arm which engages beneath the sheet and lifts it, in conjunction with rubber tipped fingers such as 44, Fig. 2, into contact with a vertically arranged apron which, with the aid of coacting rollers, deposits the sheet on to a delivery board arranged above the platen. The inking-rollers receive their ink from a distributing drum 19, Fig. 1, arranged on the shaft of the lower or upper sprocket wheel carrying the chains 10 and driven in a direction opposite to the chains. Ink is applied to the drum 19 from a duct roller 22 by a messenger roller 20 and distributing- rollers 21.