GB649153A - Improvements in or relating to printing machines - Google Patents

Abstract

649,153. Printing-machines. LEATHLEY PUBLICATIONS, Ltd., and SCHUENEMANN, C. E. April 13, 1948, No. 10279. [Class 100 (ii)] Tripping-arrangements.-A cylinder trip for a printing couple comprises a sun wheel and an internally-toothed ring both engaging an intermediate planet wheel and both provided with locking devices permitting uni-directional rotation in opposite directions, the planet wheel being moved by a pivoted lever, biassed in contact with a cam driven by the machine main shaft but normally releasably held inoperative against the bias force, either the sun wheel or the toothed ring being rigid with a rotary release shaft whose intermittent movements, produced as the pivoted lever is rocked by the cam, are used alternately to apply and release the printing pressure. As shown, a main shaft 3, driving an impression cylinder 9 and an engraved copper &c. intaglio printing cylinder 10 through equal gears 5 ... 8, carries a cam 21 against which a roller 22 on the lever 23 is pressed by a spring 24 whenever a hand-, foot or solenoid-operated latch 25 is withdrawn ; the lever 23 is linked to a rotatable spider 29 carrying one or more planet wheels 31 meshing with a sun wheel 30 and a ring 32 ; the sun wheel is fixed to the release shaft 18 and anti-clockwise rotation thereof is prevented by spring pawls 19, 20 engaging discs 16, 17, while clockwise rotation of the ring 32 is prevented by a spring pawl 33 engaging ratchet teeth on the ring. Rods 14, 15 connect the discs 16, 17 to the eccentric bearings 12, 13 of the cylinder 10 so that rotation of the rod 18 produces a 60 degree oscillation of the bearings. In operation the latch 25 is momentarily withdrawn to allow the lever 23 to follow the cam 21 for one revolution, thus producing first a 90 degree anti-clockwise rotation of the ring 32, then a 180 degree clockwise rotation of the shaft 18 whereby the bearings 12, 13 will be rotated anti-clockwise from the printing position shown to the release position ; a further withdrawal of the latch 25 results in another 180 degree clockwise rotation of the shaft 18 to return the bearings 12, 13 to the printing position.