Patent GB-199904-A (GB)
Title: Improvements in printing machines
IPC: B41F5/22
Filed: 1922-05-17
Abstract: 199,904. Barker, R. W., (American Bank Note Co.). May 17, 1922. Offset machines; inking-apparatus ; tripping- arrangements.-A rotary offset printing-machine is constructed with a number of relief design cylinders as 6, 7, 8, 9, Fig. 2, which each print impressions in different colours corresponding to part of a design on a collecting or offset cylinder 1 with which coacts an impression cylinder 2 and delivery cylinder 3. The design cylinders are inked by rollers 10, 11, fitted with distributing rollers 15 and receiving ink from rollers 13 supplied from fountains 16, 17 by messenger rollers 22, 23, carried by an oscillating frame 19 which moves one roller 23 from the duct roller 24 to an inking-roller 13, and another roller 22 from roller 13 to a ductor roller 24. The rollers 22, 23 are fitted with distributing-rollers 27, 28, and distributing-rollers 14 are fitted to the rollers 13, the rollers 14, 15 being capable of being reciprocated longitudinally to an adjustable extent in order to blend inks of different colours when the foun. tains 16, 17 are arranged to supply stripes of different colours to the rollers 13 and from these to the design cylinders. To cause these stripes of colour to register exactly the fountains are fitted with adjustable partitions, and alternate sections of these fountains are left empty. The adjust able partitions are staggered slightly so as to cause the right edges of the stripes of colour proceeding from the fountain 16 to register exactly with the left edges of the stripes from the fountain 17. The printing-cylinders are arranged so as to be circumferentially adjustable relatively to their driving-gears which all gear with a large gear on the collecting cylinder, and these cylinders are mounted in eccentric bushes 29, 30, 31, 32, Fig. 3, which together with the bush 33 in which the impression cylinder is mounted can be simultaneously rotated to throw the cylinders out of printing relation to the cylinder 1. The trip mechanism is shown in Fig. 3, and it is so arranged that any of the cylinders can be disconnected from its action, and be left permanently out of contact with cylinder 1. The means for moving the cylinder bushes is controlled from a shaft 70, Fig. 3, connected by cranks and links 76, 77, to shafts 34, 37, which are connected by links 53, 69, to other shafts 35, 36. Each shaft as 34 is fitted with a freely-mounted double crank and with a fixed crank connected by a detachable link to the freely-mounted crank when the cylinder adjacent to it is to respond to the motions of the shaft 70. The detachable link is disconnected when either of the cylinders is to remain out of action. The shaft 70 is controlled by an oscillating thrust-member 84 operated by a lever 82 and cam 81. A rod 85 with springs 86, 87 bearing on the member 84 causes this member to engage either a roller 72, or 73 on an arm 71 on shaft 70 and so moves the shaft 70 to cause the cylinders 6 - - 9 to be in operative or inoperative positions. The rod 85 is operated by a crank 89 or by a pinion and rack 94 connected to a pedal 92. The eccentric bushes 29 - - 32 may be fitted with handles 96 for direct operation. The inking-mechanisms for the design cylinders are similar to one another, and that for cylinder 8 is shown in Fig. 11. The rollers 10, 11 are mounted in a spring-pressed frame 97, pivoted at 98<a> about which the frame is turned, when it is desired to trip the rollers 10, 11, by the action of a cam 100 and lever-and-link mechanism 102, 103, 104, 107. This action also trips both messenger rollers 22, 23, a stop arm 109 on the pivot. 98<a> acting to hold the frame 19 in an inoperative position. The frame 19 is normally oscillated by a cam-operated lever 120, 121, which transmits motion to a lever 112, connected by links to the pivot 115 of frame 19, by means of a swivelled member 124 which normally acts on a screw 123 in an arm 122 of the lever 112. When the arm 109 is raised it rotates the member 124 to turn its flattened part towards the screw 123 and so prevents the roller 23 :'rom being moved into contact with the duct roller. The arm 109 also holds the arm 22 and prevents the roller 23 from moving into contact with the inking-roller 13. When it is desired to mix the ink of adjoining colours to secure a blended effect the rollers 14, 15 of the various inking-mechanisms are reciprocated longitudinally by means of a series of interconnected levers and the levers being fitted with rollers which engage grooved pulleys fixed on the shafts of the rollers 14, 15. The rollers 14, 15, of the cylinders 6, 7 are operated from an oscillating shaft 135, Fig. 7, oscillated by an eccentric 136 and a link. The shaft 135, by means of links connected adjustably to slotted quadrants, imparts variable oscillating motions to shafts 143, 148, 139, 137, all fitted with levers for oscillating the rollers 14, 15. The shaft 135 also imparts a variable motion to a shaft 153, and a vertical shaft 159 from which the reciprocating motions of the rollers 14, 15 of the other design cylinders are obtained. The inking- mechanisms are mounted in adjustable carriages 165 operable by rack-and-pinion mechanism, and adapted to be removed from the cylinders when making ready.