Patent GB-752025-A (GB)
Title: Improvements in or relating to multi-colour textile printing machines
Inventor: SCHWENKE ALWIN
IPC: B41F13/14
Filed: 1954-06-09
Abstract: 752,025. Printing-machines. VEB TEXTILMASCHINENBAU ZITTAU. June 9, 1954, No. 16951/54. Class 100 (2). Multicolour printing - machines.-A multicolour textile printing-machine comprises a series of printing units, one or two printing cylinders co-operating with each impression cylinder, each impression cylinder being adjustable towards and away from the printing cylinders and all printing cylinders being circumferentially and axially adjustable for register but otherwise fixed. The textile web may be guided through the machine in straight line as shown in Fig. 2, or as shown in Fig. 10, in a wavy line so that the web engages each printing cylinder over an arc. In the latter form two printing cylinders 9 co-operate with each impression cylinder 17. In the form of Fig. 11, the web is printed on one side by cylinders 9 co-operating with cylinder 17, then reversed over a roller 57 and printed on the other side by cylinders 9<SP>1</SP> co-operating with impression cylinder 17<SP>1</SP>. The machine, as shown in Figs. 1 and 2, consists of side frames 2 and 3 and a crossframe 4. The cylinders are mounted in bearings in the side frames, each unit being separated at lines 5 from the next so that as many units as are necessary can be put together to form the machine. The printing cylinders are driven as described below and the impression cylinders are frictionally driven from each other by pairs of intermediate rollers 20, Fig. 2, the rollers of each pair being urged towards each other. Impression adjustments.-The impression cylinders are carried in bearing-blocks slidably mounted in parallel guides. A coarse and fine screw adjustment for the printing pressure is provided controlled by handles 18, 19. The pressure of the screws is transmitted to the bearing blocks by way of an uncompressible pulpy mass, e.g. of polyvinylchloride mixed with a softener, this mass being contained in a cylinder and acted upon by pistons connected to the screws. Printing cylinders.-Each printing cylinder comprises a driving stub shaft 8, Fig. 7, an intermediate shaft 7 and a guide stub shaft 6. The printing surface is carried on a sleeve 9 mounted on the shaft 7. The printing cylinder may be attached to the stub shafts 6, 8 by readily releasable means so that it can be withdrawn leaving the stub shafts in position but this allows excessive deflection under printing pressure. To avoid deflection, in the construction described, internally toothed rings 14 welded to the ends of the shaft 7 co-operate with external teeth 15 formed on the stub shafts 6 and 8. The shaft parts 6, 7, 8 are secured together by a central rod 12 fixed in stub shaft 6 and tightened by a nut 13 bearing on the end of stub shaft 8. Centralizing means may be provided between the stub shafts 6, 8 and the central shaft 7. These may comprise double cone members 10 or ball and cup members 11. Adjustment for registration.-In the form of Fig. 4, the drive to each printing cylinder is transmitted through a helical-toothed gearwheel 21 slidably, but not rotatably connected to the stub shaft 8, the driving wheel 22 being narrower than wheel 21. Axial-displacement of wheel 21 causes circumferential adjustment of the relative position of the printing cylinder. The wheel 21 may be displaced to such an extent that it becomes disengaged from the wheel 22 so that the printing cylinder may be shifted as desired to provide a coarse adjustment. This disengaging displacement is effected by a handle 25, rotation of which is transmitted through a shaft 59 and an arm to a slider 24 having a claw 23 engaged in a groove formed in the gear-wheel 21. The fine adjustment is effected by a worm 30 rotatable by a handle 29 and engaging a toothed gear 26 threadedly mounted on a screwed sleeve 27 fixed to a frame member 28. Rotation of the handle 29 thereby causes axial displacement of the gear 21. The direction of the teeth on the driving gears is such that gear 21 is always urged against the worm gear 26. Axial adjustment is effected by a pair of worm gears 31, 32 operated by worms 37, 38 on sleeve 59a and spindle 66. The sleeve and the spindle are geared together at 40 for equal and opposite rotation by a handle 39. The gear 31 is mounted on a screwed shaft 33 and gear 32 is mounted on sleeve 27. A flange 8a carried on an extension of the stub shaft 8 passing through sleeve 27 is located between gears 31, 32 by bearings 36 so that rotation of handle 39, causing similar displacement of gears 31, 32, effects axial register of the printing cylinder. In another form there is only one worm gear, a spring being provided bearing on the end of the stub shaft 8 to maintain the flange in engagement with the gear (as 32) which is axially displaceable to effect register as before. Inking.-Each printing cylinder co-operates with a doctor blade 41 mounted on an axiallv slidable rod 43 spring-loaded so that one end bears on an upstanding arm 55, Fig. 4, carried on a slider 54. This slider is oscillated by a rocker 50 pivotally mounted at 51 and having a yoke co-operating with a cam 49 at the lower end. The pivotal mounting at 51 may be disconnected to interrupt the oscillation by a hand-lever 52. Each doctor blade is detachably mounted on the corresponding shaft 43 by a mounting bar 41a, Fig. 6, engaging at each end in shaped slots 42a in brackets 42 on shaft 43. The bars 41a with the doctor blades may be lifted out by handles 58. The shaft 43 is rotatable to bring the doctor into engagement with the cylinder by a worm 46 on a spring- loaded shaft rotatable by a handle 45. The worm shaft is carried on a bracket 44 oscillating with the shaft 43 and guided by a roller 67 on a support bracket 56 for the shaft 43. When the handle 45 is rotated the worm 46 engages a toothed quadrant 47 on shaft 43 and turns it so that the blade 41 is forced against the cylinder 9. The spring 48 loading the worm shaft determines then the bearing pressure of the blade. The shape of the slots 42a in brackets 42 is such that in the operative position the pressure on the doctor blade causes the mounting bar to be securely retained and to be released for removal when the blade is rotated out of engagement with the cylinder.