Patent GB-188452-A (GB)
Title: Means for automatically transferring designs on to lithographic printing plates
IPC: B41C1/10
Filed: 1921-09-14
Abstract: 188,452. Gardner, W. Sept. 14, 1921. Printing on curved surfaces; printing - surfaces.- A rotary machine is adapted automatically to transfer a number of repeats of a design carried by a master plate on to a lithographic printing- plate mounted on a cylinder 2 the repeats being arranged in spaced relation both longitudinally and circumferentially of the cylinder. As shown, the cylinder 1, Fig. 1, carrying the master plate is in contact with a cylinder 2 which off-sets the design on to a plate carried by a large cylinder 3. The cylinders 1, 2 are adapted to transfer rows of repeats of the design on to the cylinder 3 and for that purpose they are mounted in a carriage 4 longitudinally slidable in vee-guides on a spring - pressed transverse slide 5. The latter is provided with roller arms 8 in engagement with adjustable cams 6 whereby the cylinders 1, 2 are moved away from 3 after each impression and returned to commence the next impression. The cylinder 3 is intermittently rotated from the cylinder 2 by gear wheels which are disengaged when the slide 5 is moved back so that the impressions are transferred to the cylinder 3 in close succession circumferentially. When one row of impressions has been completed the revolution of the cylinder 3 is completed by means of a constantly rotating gear wheel 45 mounted in sliding bearings and raised by a cam into engagement with a gear wheel on the cylinder 3. The revolution is accurately adjusted by a V-stop 63 Fig. 8, raised into engagement with a stud 65 on the cylinder bv a cam 64. Meanwhile the slide 4 is moved longitudinally into position to commence another row of impressions by a screwed spindle 29 engaging a nut thereon. The spindle 29 is rotated by exchangeable gears 13, 12, 11 the shaft of the latter being revolved through a friction clutch 33, Fig. 7, one half of which is rotated by a coupling 31 operated bv a cam 32 rotated from the cylinder 3 through chain gearing. The shaft 11<a> is normally prevented from rotating by a projection 35 thereon engaging a spring-pressed sliding pin 34. The latter is withdrawn by a cord fixed to a stud 36<a> slidably engaging a semi-circular groove in one half 36 of a coupling 37 which is closed by a cam 38 driven from the cam 32. The arrangement is such that the part 36 makes a half revolution and holds the pin 34 retracted while the part 35 makes one and a quarter revolutions. The stud 36<a> then slides to the top of its slot the pin 34 returns and stops the shaft 11<a> at the end of its second revolution. A similar cam and clutch arrangement to those described above is used to drive the cam 64. The roller 1 is inked by rollers 21, 22, 23, the latter two being separated to interrupt the inking by a wedge 24 raised by a pivoted lever. Damping- rollers may also be provided. Fig. 6 shows the details of each main cam 6 which comprises two coned parts 47, 48 mounted on the shaft 46 and clutched together by tightening a nut 51. Screws 53 are provided for separating the parts and a member 49 fixed on the shaft provides an abutment for locking the part 48 in adjusted position by means of screws 50, 51 and also for effecting a fine adjustment. A pointer 62 and a scale are provided to indicate the adjustment.