Patent GB-495456-A (GB)
Title: Improvements in or relating to printing machines
IPC: B41F13/46
Filed: 1937-05-14
Abstract: 495,456. Printing-machines. QUICK, C. G., SKINNER, C. H., and EVANS, M. E. B. May 14, 1937, No. 13694. [Class 100 (ii)] A late-news printing-mechanism is provided with means to receive a printing-plate in a stationary non-printing position below type height, means to rotate the plate at printing speed, and means to transfer the rotating plate to a printing position at type height, the longitudinal displacement of the plate being effected only while the plate is out of contact with the face of the web to be printed. Means may also be provided to remove a plate from printing position as another plate is moved into printing position. A loading head 5, Fig. 1, to hold a plate P below type height, is loose upon the shaft 2 of the late-news printing cylinder 1 which co-operates with the impression cylinder 5, and the head 6 and cylinder 1 are provided with bars forming between them grooves to receive the late-news boxes 9. Secured to one end of the head 6 is a drum 11 within which is a block 14 keyed to the shaft 2 and carrying radially slidable clutch blocks operated by levers pivoted to the block 14 and actuated by cams on a sleeve 20 slidable on the shaft 2. The cams are of such form that as the sleeve 20 is moved toward the head 6, the clutch blocks first engage the drum 11 to speed up the head 6 and are then withdrawn to allow slip so that a pin 21 carried by the sleeve 20 can enter a hole in the drum 11 to effect a positive drive of the head with its dovetail grooves in register with those of the cylinder 1. The axial movement of the sleeve 20 is effected by a lever 26 actuated by a cam driven by gearing from a hand-wheel 33. During the initial movement of the lever 26 a brake 41 is withdrawn from the outer surface of the drum 11. The loading head 6, Fig. 6, is provided with pushers 43, one for each box 9, mounted to slide in slots 47 in the head and provided with pins 44, 45 which, during the sliding movement of the pushers, move in side recesses 46 in the grooves 47. Normally the pushers are tilted by the action of springs 50 so that the pins 44 lie in side extensions 49 of the recesses 45. The box 9 comprises a stationary part 55 and a part 55 which can be withdrawn from the part 56 for the insertion of the late-news plate or type and, when loaded with the plate &c., the part 55 overlies a flange 66 on the front of the pusher and holds it depressed so that the pin 44. lies in the recess 46 and a gap 53 in the pusher operatively engages a sleeve 52 slidable on the head 6. The sleeve 52 is actuated by the hand wheel 33, Fig. 1, through gearing and a screw 71, threaded through a bracket 70 engaging a groove between flanges 67 on the sleeve. Those pushers which have been engaged with the sleeve by the loading of the boxes 9 are thus moved to push the boxes into the cylinder 1, Fig. 8, and into engagement with front stops 77. The cylinder 1 comprises outer parts 72 and an inner part 73 having inclined engaging surfaces and the parts 72, when receiving the boxes, are held by springs 86 in their lower position so that during movement of the boxes up to the stops 77, their printing- surfaces are below type height. When the boxes engage the stops 77 further movement of the pushers, by engagement of inclined parts 76 on them with inclined surfaces 75 on the parts 72, moves the parts 72 longitudinally to move the boxes 9 radially to type high position. The parts 72 are held in this position by spring catches 78 and stops 84 are raised by springs 85 to engage behind the boxes. Fig. 12 shows a modification with an unloading head 95 normally loose on the shaft 2, but adapted to be driven by a gear 100 on the loading head 6, through intermediate shaft 98 and gears 99, 97, 96 so that it is speeded up in register with the cylinder 1 simultaneously with the head 6. A sleeve 102 slidable on the head 95, and having bars forming dovetail grooves to receive the boxes from the cylinder 1, has a number of blocks 110, one for each box position which can be turned to present a recessed or unrecessed side to the ends of plungers 112 mounted in the head. Those blocks whose unrecessed sides are presented to the plungers act, upon sliding of the sleeve 102 'towards the cylinder 1, to move the corresponding plungers 112 so that their outer ends actuate levers 114 to depress the stops 77 clear of the boxes 9 and release the catches 78 so that the parts 72 move down the part 73 to bring the boxes on the cylinder 1 below type height. Wedge surfaces on the parts 72 at the same time engage and depress the stops 84. The boxes on the cylinder thus released are free to be moved by the incoming boxes on to the sleeve 102. This sleeve is actuated at the proper time relatively to the pushers 43 by linkage 106, 107, 108 from a cam 123 actuated by the hand wheel 33. Instead of providing the wedge parts 72, 73 on the printing cylinder, they may be constituted by an assembly movable bodily from the loading head to the printing cylinder, the pusher engaging the lower part of the assembly. Specification 128,489, [Class 100 (ii)], is referred to. The Provisional Specification states that the clutch for speeding up the loading head may be of the construction described in Specification 384,117.