GB192776A - Improvements in or relating to platen printing presses - Google Patents

Abstract

192,776. Spoerl, J. H. [Firm of], and Schlesinger, A. Nov. 8, 1921. Grippes; sheet-registering devices; sheet - separators. - In a platen printing-machine of the vertical bed type, in which the platen is guided to move so that it is always parallel with the bed and a register plate, which during the impression is supported on the face of the platen, is movably connected therewith and swung upwards when the platen recedes from the bed into position to receive a sheet, a pneumatic feeder is provided comprising a suction nozzle carried by levers rocked by the platen, together with a register bar and nippers for holding the sheet on the register plate after it has been fed. The sheets are fed from a pile on an automatically raised support 51, Figs. 8 and 10, by a suction nozzle 55 carried by a frame 56 on levers 57, 58 oscillated by a roller 62 at the rear of the platen engaging an extension of the lever 57. The front edge of the sheet is registered against a register bar 64 which is hinged to the register plate 6 and has been lifted in a manner set out below prior to the feeding of the sheet. As the suction nozzle 55 moves to the left, a pawl 70, Fig. 10, thereon slips over the lifted register bar 64 but engages therewith in its return journey so as to turn said bar 64 on its hinge, the spring 67 then clamping it down on the front edge of the sheet. The latter is also clamped by nippers 76 pivoted on a shaft 78 carried by spring-pressed rods 72 guided in sleeves 71 pivoted at 73 to the sides of the register plate 6, the nippers 76 being connected by links 77 to the cross-bar 8 on the platen so that they are forced down on the sheet as the platen moves into printing position. When the register plate 6 is pressed by the platen against the forme, one pair of pawls 79 connected to the machine frame engages the nipper shafts 78, as shown in Fig. 12, and another pair of pawls 80 engages pins 66 on the register bar 64, whereby, when the register plate commences to move away from the forme, the nippers 76 and the register bar 64 are lifted away from the printed sheet so that the latter can drop down, the release of the sheet being assisted by pins 84 on the bar 64. Rods 85, connected to the links 77 and guided by slots 86, engage arms 68 at the sides of the register bar 64 so as to swing up the latter in readiness for a sheet to be fed when the register plate is at its highest position. The pawls 79, 80 are carried by a rocking lever 81, Fig. 8, and moved to the left by means of the crank and connecting-rod 83, 82 out of the way of the inking-rollers when the latter are passing over the forme.