GB521223A - Improvements in or relating to sheet-fed printing presses - Google Patents

Abstract

521,223. Printing - machines; feeding and delivering sheets. STOBB, A. Nov. 12, 1938, No. 32985. Convention date, Nov. 16, 1937. [Classes 100 (i) and 100 (iii)] A printing-machine is constructed with means carried by the impression cylinder 14 for separating sheets in succession from a pile 20 preferably carried on a rising support arranged within the frame 11 of the machine, and the sheets are delivered to a table 84 arranged close to the pile table 85 and operated by a common mechanism which raises the table 85 and lowers the table 84 at the same rate. The inking and damping mechanisms 17, 16 are preferably carried in a frame 15 which slides in the frame 11 and can be removed readily to permit of access to the plate or offset cylinders of the machine.. The feed table 85 is connected to one side of a chain 86 operated in unison with the press, and the delivery table 84 to the other side of the chain. The connection in each case is an adjustable one associated with a handwheel 95 which by worm mechanism rotates a sprocket 89 or 90 which connects the tables to the chain 86. The tables are thus adjustable independently. The impression cylinder 14 is formed with an open segment 24, Fig. 5, in which is arranged a suction separator in the form of a pivotally mounted plate 25 formed with a series of suction apertures 36, the plate being integral with a gear 28 which is oscillated by a gear segment 29 on a shaft 31 which oscillated by a stationary cam 34 engaging a roller 33 on an arm secured to the shaft 31. When the plate 25 reaches a position above the front edge of the pile it is moved in a reverse direction to the motion of the cylinder and remains practically stationary relatively to the pile. Owing to the eccentric mounting of the plate 25 it is projected radially of the cylinder so as to contact with the top sheet. Prior to this the top sheet is buckled and registered longitudinally and laterally by means of an inclined roller 65 which is carried by slides reciprocated to and from the pile by cams 71. The front edges of the top sheets are held by projecting feet 77 on a hold-down plate 76 to which are adjustably fixed lateral gauges 80 for side-registering the sheets. Owing to the action of the feet 77 and roller 65 the top sheet is buckled and is then taken by the suction nozzles 36. The pile is also controlled by rear gauges 56 adjustable by means of lever 57, gearing 60, 61 operated by handle 58, and air blasts from nozzles 74 assist separation of the sheet. The pile is controlled by adjustable front gauges 50 and the nozzles 36 are controlled by valves 40 which permit the outside ones to be cut-off when dealing with narrow sheets. After each sheet is separated from the pile it is clamped to the rear edge of the opening 24 by means of grippers41 on a shaft which is geared to the shaft 35, and is arranged so that the grippers clasp the sheet just after the nozzles 36 separate it. The grippers hold the sheet as the nozzles are withdrawn into the cylinder, and finally transfer it to delivery grippers 82.