Patent GB-349279-A (GB)
Title: Improvements in and relating to high-speed cylinder printing presses
IPC: B41F3/00
Filed: 1930-05-12
Abstract: 349,279. Printing- machines. TRIGGS, W. W., 57, Lincoln's Inn Fields, London.-(Automatic Akt.-Ges. f³r Automatische Druckmaschinen; 139, Alte Jakobstrasse, Berlin.) May 12, 1930, No. 14599. [Classes 100 (i) and 100 (ii).] Cylinder machines; feeding webs.-In a web-printing oscillating-cylinder printing- machine the web is arranged to pass round the segmental part 23 of the impression roller B<1>, and is then passed through the interior of the cylinder B<1> and preferably over its axis of rotation to the intermittently driven main feed mechanism D. The web is led from a roll 2 over rollers 7, 8, 9, to a constantly driven roller 10 co-operating with a pressure roller 11. The speed of the roller 10 can be varied by means of a change-speed belt drive 45, 45<1>, controlled by a handwheel 14. From the rollers 10, 11, the web is fed with a loop 5<1> and is then passed through braking rollers 15 to equalizing rollers 16, 17, 20, of which the roller 17 is retracted by a rack 19 geared to the oscillating impression cylinder in order to pay out sufficient web for the impression which is effected after a clamp 25 presses the web against the leading end of the impression segment 23 to which the web is guided by rollers 21, 22. In the machine shown impressions are made in two superposed colours from formes 62, 63, mounted in a bed B which is reciprocated by racks 59, 60, and a reciprocating pinion 59<1>, operated by a pitman 65 from a crank disc 50 on a shaft 49. The main feed roller 28 is driven' intermittently by a free-wheel drive from a toothed segment 37 which is oscillated by adjustable crank mechanism 40, 41, 42. The roller 28 remains idle during the printing operation, and subsequently it draws forward the required length of paper while the bed returns idly under the raised impression cylinder B<1>. The length of paper fed is equal to the length of either forme 62, 63 and the margins. The web is guided to the roller 28 by guides 26, 27 and a roller or bar 81, Fig. 3, or a pivoted tensioning bar 81<1>, Fig. 7, may be used in place of the gripper 25 and bar 81. The printed web may be passed through auxiliary treating devices mounted in a support E such as numbering mechanism 36<1>, perforating mechanism 36, to auxiliary feed mechanism 30 driven in synchronism with the main feed D. Perforating and ruling mechanism 31, a longitudinal cutter 311, and transverse cutter 31<11> which allows the cut sheets to fall on an adjustable delivery device F may also be used; or the printed web may be wound up into a roller by passing it over a roller 78<1> to form a loop, and then leading it between rollers 77 driven by a belt from the constantly driven feed roller 10. The roll 78 of printed paper is pressed by a roller 103 movable in a guide 102 which also guides the shaft 101 of the rewinding roller. In a modification, Fig. 8, the formes 62, 63 print perfected impressions in co-operation with impression segments 23b, 23c, respectively, on a web which is fed from a roll 2<1> arranged with its axis at right-angles to the cylinder B<1>. The web is turned by a bar 80 before entering the feed rollers 10, 11. After receiving the first impression the web is led across the path of the unprinted web by means of guide rollers 86 .. 91, and is returned to the segment 23c to receive the perfected impression. Set-off, preventing.-To prevent smudging of the printed sheets a set-off web 74 may be led from a roll 72 and may join the printed web as it passes between the rollers 28, 29, in which case sheets cut from the web 74 will be interleaved between the printed sheets. Alternatively the web 74 may be wound up on the roll 78 together with the printed web. Tripping-arrangements.-The cylinder B<1> is tripped on the reverse motion of the bed by means of a cam 51 on the shaft 49 which by means of lever-and-link mechanism 53, 54, 56, 57, 581, 58 oscillates eccentric bearings 58<11> in which the cylinder B<1> is mounted.