Patent GB-351970-A (GB)
Title: Improvements in and relating to the locking of stereo plates or printing surfaces tothe cylinders of rotary printing machines
IPC: B41F27/10
Filed: 1930-04-01
Abstract: 351,970. Printing-surfaces. FOSTER & SONS, Ltd., J., WILKINSON, M. L., and BRADSHAW, R., Soho Foundry, Preston. April 1, 1930, No. 10359. [Class 100 (ii).] In a locking arrangement for the printing- plates on a four - plate wide printing - cylinder in which the inner plates may be unlocked without unlocking the outer plates, all the locking dogs fcr the plates are operated by screwed rods from the ends of the cylinder. In one form, Fig. 1, the inner plate 19 is locked between the usual margin ring 18 and a number of dogs 2 mounted in grooves 6 in the cylinder and operated by screwed rods 4 to which are fixed gear wheels 4a. The outer plate 20 is locked between the dogs 2 and dogs 3 operated by threaded sleeves 5 mounted on the rods 4 and having secured to them gear wheels 5a. The gears 4a, 5a of all the rods 4 and sleeves 5 relating to a pair of plates 19, 20 mesh with intermediate gears 8, 7 respectively, Fig. 5, the gears 8 being loosely mounted on the spindles 7a of the gears 7. One of,the gears 8 is provided with a clutch face 8b co-operating with a clutch face 9a on a cap 9 slidable on the spindle 7a and provided with a squared end to receive a spanner. When the clutch faces are in engagement all the gears 7, 8, 4a, 5a are operated simultaneously and the dogs 2, 3 can be withdrawn to release the plate 19 without releasing the plate 20. By disconnecting the clutch faces, the gears 7, 5a may be operated alone to lock and unlock the plate 20 independently of the plate 19. A distance piece 21, Fig. 1, between the dogs 2, 3 may be provided to support the plate 20 above the grooves 6. In a second form, Figs. 7 and 9, the outer dogs 23 are threaded upon spindles 24 and the inner dogs are loosely mounted on the spindles to which are fixed collars 27. The spindles 24 are provided with gear wheels 24a and with squared caps 25, and are mounted in a thrust plate 26 movable towards and away from the end of the cylinder by turning a screw 32, Fig. 9. The gears 24a are connected together by idle gears 28 for simultaneous operation. By operating the screw 32 the dogs 22, 23 can be withdrawn together to release the inner plate 19, and by turning the screws 24 by applying a tool to one of the caps 25, the outer dogs 23 alone can be operated. If an outer plate is absent, the inner plate can be locked by operating the screws 24 to cause the dogs 23 to press distance pieces 28b into contact with the dogs 22. In a further form, Fig. 11, means are provided to adjust the dogs to suit plates having different numbers of columns. The outer dogs 23 are threaded on screws 24 operated by gears 24a and thrust plate 26 similarly to the screws 24 of Fig. 7. The inner dogs 22 are threaded on screws 41 having a pitch of half that of the screws 24, and to the ends of the screws 41 are secured blocks 42 having clutch faces 43 co-operating with clutch faces 39 on blocks 33 slidable on the screws 24 and held by a spring-pressed ball 35 with the clutch faces in engagement or disengaged. Screws 40 connect the screws 24 with the blocks 42. With the clutch faces disengaged, the plates can be locked and unlocked in the manner described with reference to Fig. 7. With the clutch faces engaged, by turning one of the caps 25, the dogs 22, 23 can be spaced apart to suit the width of the plates a fine adjustment being effected by turning the blocks 42 by means of a tommy bar. The clutch faces are then disengaged. Instead of separate dogs, circular or semicircular clamping rings may be used.