Patent GB-768968-A (GB)
Title: Improvements in or relating to an apparatus for removing ink from an intaglio printing plate
IPC: B41F9/10
Filed: 1955-04-01
Abstract: 768,968. Intaglio printing-machines. AMERICAN BANK NOTE CO. April 1, 1955 [April 2, 1954], No. 9527/55. Class 100(2) An apparatus for removing ink from the relief parts of an intaglio printing plate comprises a resilient roller engaging the plate, an adjusting device to adjust the roller through a range of positions toward and away 'from the plate, means for moving the resilient roller through this range of positions without the setting of the adjusting device, a second roller having a surface of hard material engaging the resilient roller, an adjusting device to adjust the second roller through a range of positions toward and away from the resilient roller, means for moving the second roller through this range of positions without moving the resilient roller and the setting of the second roller and its adjusting device, means removing ink from the second roller and driving means for rotating the rollers at predetermined speeds relative to the plate and to one another. As shown, the plate cylinder 1, Fig. 1, rotates counterclockwise past the ink removing mechanism comprising a doctor blade mechanism 2 and shoes 3 and 4 over which a web of crepe paper 5 is fed from a supply roll 6 to a take-up roll 11. The doctor blade mechanism 2 comprises a rubber roller 12, Fig. 3, which engages the plate cylinder 1, a steel roller 14 engaging the rubber roller 12, and a doctor blade 75 which scrapes the surface of the roller 14. ink removed by the blade 75 drops into a pan 15a, Fig. 1. The' roller 12, Fig. 3, has a hard outer shell 12a of wear-resistant rubber and a core 12b of softer rubber carried on a shaft 15 journalled in a block 17 slidable in a guide 18 towards and away from the plate cylinder. A yoke 20, Fig. 4, is rotatable on a pin 19 journalled in the block 17, the yoke having arms 20a and 20b and a pivot pin 21 extending between the arms. The pin 19, Fig. 6, extends through shoes 22 and 23 slidable in the guide 18 and engages a screw socket 24 on an adjusting screw 26. The screw 26 is threaded in a sleeve 27 slidable in a cap 28 and carries a knob 30 and index member 31 having notches, not shown, which co-operate with a spring finger, not shown. An index finger 33, Fig. 2, not shown, on the cap 28. co-operates with a scale 31a on the member 31 to indicate the angular setting of the screw 26. The sleeve 27, Figs. 3 and 6, is non-rotatable in the cap, but is slidable by a rack 27a engaging a pinion 34. To adjust the rubber roller 12 with respect to the plate cylinder 1 the spring finger is disengaged from the member 31 to permit rotation of the knob 30 to advance the screw 26 relatively to the sleeve 27, thus moving the shoes 22, 23 and block 17 to- The roller 12 is separated from the plate cylinder, e.g. for cleaning, by rotating the pinion 34 through a shaft 35, Fig. 1, a crank 37, link 38 and cranks 38a, 38b; the roller 12 is returned to its original preset position after separation. The roller 14 is adjustable with respect to the roller 12 by a screw 43, Fig. 4, engaging a yoke 42 rotatable on a pin 41 carried by a block 40 in which the shaft 16 of the roller 14 is journalled. The pin 21, Fig. 3, carries a wing 21a having a threaded handle 45 which when rocked actuates a linkage comprising the yoke 42 and yoke 20, the axis of the pin 21 being slightly to the left of a line joining the axis of pins 19 and 41. By moving the handle 45 counterclockwise the shaft 16 is moved from the shaft 15. Actuation of the handle 45 in the opposite direction restores the shaft 16 to its former position without altering the previous adjustment as determined by the screw 43. The block 40, Fig. 4, carries an arm 46 having a hub 47 which receives a shaft 48 carrying a guide block 49. The block 49 has a slide 49a receiving a socket 50 engaged by an adjusting screw 51 clamped in a plate 49b by a screw 49d. The socket 50 receives the hemispherical end 52 of a rod 53 slidable in a doctor blade supporting bar 54. Adjustment of the screw 51 by a knob 51a adjusts the doctor blade 75 carried by the bar 54 with respect to the roller 14. The bar 54 may be removed by axial movement so permitting removal of the hemipherical end 52 at one end of the bar 54 from its socket 50. A screw 61, Fig. 12, threaded in an arm 60 pivotally mounted on a plate 59 attached to the arm 46, adjusts the angle between the bar 54 and roller 14, Fig. 3. The arm 60 may be swung out of operative position beneath the bar 54 when it is desired to clear or remove the blade 75. The shaft 15, Fig. 3, carries a gear 63, while shaft 16 carries a gear 64, the gears 63 and 64 being driven by a gear train comprising pinions 65, 66, 67, 69, 70 and 71, Fig. 2, not shown. The rubber roller 12, Fig. 3, is driven in the same direction as the plate cylinder 1, but at a lower speed preferably 76.6 per cent of that speed, while the roller 14 is driven in the opposite direction to the roller 12 and at a lower speed preferably 36.6 per cent of that speed.