Patent GB-606285-A (GB)
Title: Improvements in or relating to a printing press
IPC: B41F21/08
Filed: 1945-12-19
Abstract: 606,285. Printing-machines. HARRIS-SEYBOLD CO. Dec. 19, 1945, No. 34388. Convention date, Sept. 4, 1941. [Class 100(ii)] A multi-colour rotary printing-machine for printing sheets is constructed so as to permit of easy accessibility to the printing- couples and so that the printing-cylinders can be removed readily onto a truck which can be wheeled between arch-like frames open on one side , the sheets being conveyed from one unit to another over the space between the frames. The printing units A, B, C, Fig 1, are preferably formed with a combination of intaglio and typographic printing-couples. The sheets are fed from a feed board 101 by a feed cylinder 103 which is given a variable motion by means as described in Specification 527,280, and the sheets pass to a transfer feed drum 107 by which they are fed to grippers of the first impression cylinder 10 which is mounted vertically above the intaglio printing-cylinder 11. From the cylinder 10 the printed sheet is transferred to a gripper unit 127 mounted on a conveyer 124, the unit 127 being locked to a transfer drum 172 while it takes a sheet from the impression cylinder 10. The gripper units 127 are constructed and operate as described in Specification 604,264 and may be associated with trip mechanism as described in Specification 604,232. The transfer drum 172 is mounted in eccentric bearings which are connected by a link 190 to eccentric bearings 89 in which the cylinder 10 is mounted, and the eccentric bearings 89 when operated by levers 95, 96 to trip the cylinder 10 also move the drum 172, but the two still remain in driving connection and in cooperative relation when cylinder 10 is tripped. The machine is driven by a motor arranged on the side of the machine opposite to the side formed with the arch recesses. and a belt-drive operates a series 'of coupled shafts 54 on which are fitted worms for driving worm wheels associated with each couple. The individual driving- gears for the various parts of each couple are formed with members adapted to prevent backlash. The conveyer chains 124 from couple A transfer the sheet to the grippers of the second impression cylinder 10 while passing around a transfer cylinder 231, and the sheet is then passed to similar gripper units 127 passing round a further transfer cylinder similar to cylinder 172. and mounted so as to be tripped simultaneously with its associated impression cylinder. The sheets are finally passed from the last couple to a delivery unit bv a conveyer with a further gripper unit 127. The conveyer 124 is constructed as shown in Fig. 5, and the sheets are carried by the upper run upwardly and over the working space adjacent unit A, and downwardly toward unit B. The printed sides of the sheets are acted upon by heated air from pipes 294 and cooled air from pipes 298, the blasts acting to direct the unprinted sides of the sheets against guides 288, 285, 291. The blasts are delivered from round apertures. In some cases the prints may be dried by gas flames directed from burners connected to a mixing chamber. The links of the conveyer 126 are guided by stationary tracks 243, 244, and then by upper tracks 246, 247 secured to a resiliently supported frame 249. Other stationary tracks 250, 251 direct the conveyer to wheel 238 and the lower run of the conveyer is controlled by tracks 253, 254 connected to a movable frame 256. The frames 249, 256 are connected to slides which can move in dovetail guides and a spring 275 tends to keep the frames raised, and so to keep the conveyer chain under tension. Racks on the frames are geared to a common pinion 266, and so if the tension of the conveyer tends to move one conveyer frame 249 upwards or downwards a reverse movement is given to the other frame. This arrangement maintains the conveyer chains taut when the impression cylinders are tripped. The printing- cylinders are so mounted that when their bearing caps are removed the bearings can be moved on rods inserted below the bearing and the cylinders can be removed on to trucks wheeled into the arch recesses. The printing-cylinder is detachably connected to its driving-shaft and can be axially adjusted for registration purposes. In a modification the sheets are carried through the printing units by the same gripper carrier and the sheets are not transferred from the carriers until the delivery pile is reached.