Patent GB-737430-A (GB)
Title: Improvements in or relating to printing machine
IPC: B41L47/46
Filed: 1953-07-21
Abstract: 737,430. Addressing and like series-printing machines. ADDRESSOGRAPH - MULTIGRAPH CORPORATION. July 21, 1953 [Aug. 28, 1952], No. 20200/53. Class 100 (2). Lithographic printing-plates are fed in succession by an endless carriage past cleaning, damping and inking stations and into contact with a blanket cylinder, the ink image being transferred to the blanket and thence by means of a platen roller to a sheet or web, the plates after passing the blanket cylinder being coated with a preservative liquid and passed to storage. In one form the carrier is a drum 60, Figs. 1 and 2, mounted on a shaft 61 and continuously rotated by a motor through a clutch 51 controlled by a pedal 56, which may also control the motor through a switch SW. The various operating units of the machine are driven from a gear 80 on the shaft 61. In another form, Fig. 20, the carriage comprises two chains 520 driven continuously, the upper run moving to the right, and the various units are driven by a motor M2 and a main drive-shaft controlled by a main clutch. Feeding printing plates to machine.-The plates D are stacked, printing-surface downwards, in a supply magazine M, Figs. 1 and 14A, whence they are fed one by one by a reciprocating picker 390 to a pair of feed wheels 372, each of which has two sets of three pins 380, which engage three holes along each side of each plate. The wheels 372 feed the plates to the drum 60, where they are held by pins 68 engaging the centre holes on each side. The edges of the plates are disposed in arcuate retaining channels 62 round the drum. The shaft 378 carrying the wheels 372 is continuously driven, and also carries a wheel 381 having a cam 382 which controls the picker 390. In the second form, Figs. 20 and 22, the plates are fed from a magazine SM to the chains 520, where they are held by pins engaging all six holes, by a picker pawl 542 operated from a star cam 549. An overload clutch is included between the rock-shaft 546 and the picker drive lever 545, and on manual rotation of a lever 567 to engage a notch in a lever 566, rearward movement of the picker is prevented to stop the feed. The forward limit of the stroke is adjustable by means of a slot 557G, and the rearward limit by a stop-screw SP. Printing-surfaces.-The printing plates are of etched or anodized aluminium foil, or zinc foil, and include a greasy lithographic image. They are also formed with three spaced holes near each side edge. When fed to the drum 60 they are covered with a preservative liquid such as gum arabic. The drum carries each plate first to a preservative-removing unit 100 where a brush 103, Fig. 2, rotates clockwise in a tank 101 of suitable liquid, so as to remove the preservative coating. Glycerine is preferably added to the liquid so as to soften the greasy image to a suitable condition for printing. The plate is then carried to a second cleaning unit 110A, Figs. 2 and 7, which supplies clear water to the plate to remove any traces of preservative remaining. The construction and operation of the unit 110A is similar to that of the damping unit described below, except that the forme roller 111A rotates clockwise so as to have a greater cleaning effect. In the second form, Figs. 20 and 22, the plates are cleaned by two units 590, 650, operated and constructed in the same way as the damping unit 110 described below, except that the forme roller 652 rotates clockwise and manually-operable clutches are provided for the drives. Damping-apparatus.-The damping unit 110, Figs. 2 and 7, supplies an ink-repellent solution such as water to the cleaned plates by means including a fountain 115, fountain roller 114 of a knurlable material, oscillating ductor roller 113, distributer roller 112 of linen, and forme roller 111 which is driven continuously counterclockwise and which, like the ductor roller, is of a soft and yieldable composition such as mulleton cloth or felt. The roller 112 is driven frictionally by the forme roller. The ductor roller is carried on a yoke 145 and oscillated under control of a cam on the forme roller driveshaft. The fountain roller is driven intermittently while in contact with the ductor roller by means including a crank 119, 118, a pawl carrier 121 rotatable on the fountain roller shaft 122, pawl 125, and ratchet on the shaft 122. The stroke of the pawl and the amount of liquid fed is adjusted by a handle 136 which turns a shroud-plate 127 having an arcuate recess to receive a roller carried by the pawl. The fountain roller can be manually rotated if the pawl is disengaged. The forme roller 111 is driven from its drive-shaft through a disc having flanges engaging a drive-plate 151. The roller 111 can be adjusted relative to the drum by rotating a handle carried on an eccentric portion of the roller shaft 153, and by rotating an eccentric bushing in which the eccentric portion is journalled, one end of the roller can be adjusted separately. The shaft 153 can be withdrawn for lubrication. In another form, Fig. 18, the unit 110 is omitted and the damping and inking units are combined, as described below. In the flat-bed form, Fig. 20, the damping unit 670 is constructed and operated in the same way as the damping unit 110. Inking-apparatus.-The inking unit 180, Fig. 7, comprises a fountain roller 210, oscillating ductor roller 215, distributer roller 183 and forme rollers 181, 182. The rollers 181, 182 are frictionally driven by the roller 183, and are carried between pairs of arms 191, 193, whereby the pressure against the drum is adjustable by turning knobs on eccentric stubs of locating shafts 199, 195, which act against the arms. Turning of the shafts through 180 degrees raises the forme rollers clear of the drum. Rotation of eccentric nuts at the other end of the rollers adjusts the alignment of the rollers. The roller 183 is reciprocated by means of a spiral groove in the shaft 184. The ductor roller 215 is carried on a yoke 214 riveted to a yoke 213. A cam on shaft 218 acts on a plate 231 on the shaft 212 of the yokes to oscillate the ductor roller. The fountain roller 210 is rotated intermittently by means of a second cam on the shaft 218 through a pawl means. The shaft 218 is driven through a clutch comprising a pawl which can be disengaged by pushing in a knob. Plates 65 on the drum hold the forme rollers out of contact therewith between printing-plates. In another form, Fig. 18, the forme roller 182 is omitted, and a roller train 407, 408, 409 supplies water from a fountain 404 to the roller 183, thus combining the inking and damping units. The roller 409 is of spiral form, having a continuous groove 409G. The rollers are journalled in rectangular bearings slidable in slots 410 in the fountain, and the pressure between them is adjustable by means of knobs 416 rotating screws 414 acting on pins 412. In the second form, Fig. 20, the inking unit 680 comprises two separate ink trains 680A, 680B, each provided with a manual drive clutch and with pressure rollers 683, 684, and otherwise constructed and operated in the same way as the inking unit 180, except that the plates 65 65 are dispensed with. Transferring ink image to blanket.-The blanket cylinder 251 is half the diameter of the drum. The inked images on the plates D, which are not inverted, are transferred as inverted images to the blanket 250. The pressure of the cylinder 251 against the drum is regulated by a handle on a bell-crank 278, which rotates plates 273 integral with eccentric bushings 272 in which the cylinder shaft 258 is journalled. In the second form, Fig. 20, the blanket cylinder 740 is above the chains 520, and a pressure roller 750 is provided. Blanket.-The blanket 250 is in two halves, and each half has one end secured over a rivet 252 and the other end connected to a shaft 254, turnable on loosening a dog 256 for tensioning the blanket. , Printing.-A web W is fed from a roll R, Figs. 1 and 2, and a platen roller 260 presses the web against the blanket through an opening in a guard plate 261, the inverted image being printed on to the web. Impression adjustment.-The roller 260 is carried on arms 262 mounted on a rock-shaft 263 and is urged against the blanket by a spring 267. The printing pressure is regulated by a handle 266 on a shaft having a cam 268 acting against an arm 264 also mounted on the shaft 263. In the second form, Fig. 20, for use where gaps between printed impressions on a web WP are not required, the impression cylinder 752 is raised out of contact with the blanket cylinder in between plates, by means including cam lugs 524, Fig. 22, on one of the chains 520, a cam roller, link 766, and arms 767, 772, while for holding the cylinder 752 out of contact as desired, a similar arm to 767 is under control of a cam on a manually-rotatable shaft. The web WP is fed from a supply roll SR to a take-up roll TR by friction only when the cylinder 752 is lowered, and the rotation of rolls SR, TR is synchronized by a chain and belt. Cleaning blanket.-The unit 280 comprises a fountain for a blanket-cleaning fluid, a fountain roller, oscillating ductor roller 281, and distributer roller 283 frictionally driven by a forme roller 285 driven by the gear 95. The ductor roller is oscillated by means of a cam 298, and the fountain roller is intermittently rotated by means including a pin 286, link 287, pawl carrier 288, pawl 289, and ratchet 293. The stroke of the pawl is adjustable by a handle 291 and a lock-screw assembly 294. In the second form, Fig. 20, the blanket cleaning unit 780 comprises a cleaning web KP fed intermittently from a roller 789 and taken up on a roller 788, being pressed against the blanket 741 by a roller 785. The roller 785 is rotated intermittently by a pawl mechanism having an adjustable shroud plate, the arrangement being similar to that for the fountain roller of the damping unit 110. The pawl is actuated by a link controlled by the cam lugs 524. The roller 789 is driven fro