GB803679A - Improvements in or relating to a drive mechanism for cylinder printing machines - Google Patents

Abstract

803,679. Printing-machines. SCHNELLPRESSENFABRIK AKTIENGESELLSCHAFT HEIDELBERG. April 27, 1956 [April 7, 1956], No. 13075/56. Class 100(2) Cylinder machines. A printing machine comprises a rotatable impression cylinder co-operating with a reciprocable type-bed, drive means for rotating the cylinder in one direction at variable speed, drive means for reciprocating the type-bed at approximately the same variable speed as the cylinder, main drive means actuating said cylinder and said bed drive means, and means adapted, during a printing operation to completely synchronize the varying speeds of the cylinder and bed. The typebed 2, Fig. 1, is reciprocated with varying velocity, and more rapidly on the leftward non-printing stroke, by a pinion 4 which also engages a fixed rack 6 and is carried on a rod 7 pivoted at 8 to a lever 9 pivoted at 10 to the machine frame. The lever 9 has on each side a slide guideway 11a in which engages a slide 12a mounted on a pin 13a. The pins are fixed to two gear wheels 14a driven at constant speed from the drive shaft 19. Also driven at constant speed is a gear wheel 26 having a pin 31 connected by a link 32 to a pin 30 on a gear wheel 29, whose axis is spaced from that of the gear 26 so that it is driven at variable speed and so drives the impression cylinder 22. The resulting rotation of the cylinder and bed are approximately synchronized, and for exact synchronization during the printing period, the rack 6 is moved longitudinally as required by means of rollers 36, 37, on the rack-supporting members, actuated by cams 38, 39 on the shaft 45 carrying the gears 14a. In another form, not shown, the variable-speed gear 29 is mounted directly on the cylinder shaft. In another form, Fig. 7, the cylinder is driven in the same way as above. The bed 62 is reciprocated by a pinion 64 on a rod 67 connected to a crank shaft 68. A gear wheel pair 74, 74a, eccentric with respect to the shaft 68, is driven at constant speed, and through a pin 72, link 71 and pin 70 on a crank 69 drives the shaft 68 and the bed at variable speed. In another form, Fig. 9, exact synchronization of the bed and cylinder is obtained by connections applied to the cylinder drive. A constantly rotated gear 101 carries a pin 102 connected by a link 103 to pin 104 on a crank 105 keyed on a shaft 106 journalled in the gear box cover 109 and in a flange on which the gear 101 is mounted. The crank 105 is thereby rotated at a variable speed. A second crank moving in unison with the crank 105 is mounted on the shaft 106, and carries a pin 117 connected by a link 116, pin 115 and link 114 to a pin 113 on a gear wheel 111 loosely mounted on the shaft 106 between the two cranks. Also connected to the pin 117 is a lever 118 carrying two rollers 119 which co-operate with stationary cam discs 121 fastened to the cover 109, whereby a corrected motion is imparted to the gear 111 and thence to the impression cylinder. In another form, Fig. 13, the cylinder is driven as shown in Fig. 1, while the bed is driven by a pinion on a crank rod connected to a variably driven crank shaft 162. A disc 163 on the shaft 162 has guide tracks 165a mounted on pins 166, 166a fixed to constantly rotated gear wheels 158, 158a.