GB367360A - Improvements in or connected with flat-bed cylinder printing presses - Google Patents

Abstract

367,360. Printing-machines. GARDNER, L. F., 173, Fleet Street, London. -(Rote-Press Akt.-Ges. ; 61, Monbijoustrasse, Berne, Switzerland.) Nov. 17, 1930, No. 34551. [Class 100 (ii).] Cylinder machines.- In a web-printing cylinder machine of the kind described in Specification 229,323, [Class 100 (ii), Printing processes &c.], in which a reciprocating slide b is fitted with two impression rollers a coacting with vertical printing-beds, and the rollers are rotated on the downstroke by means of segmental pinions g engaging fixed racks h, the drive of the impression rollers is controlled by means of pivoted racks p which can be brought into engagement with the teeth of auxiliary wheels n, Fig. 2, secured to the pinions g; the wheels n having teeth corresponding to the gaps in the pinions g. Each bed is fitted with two pairs of racks p which are pivoted to the bed at o and are interconnected by a link r. The racks are oscillated from a cam s on the shaft of the crank which reciprocates the slide b. The cam s actuates a lever u connected to a pair of thrust-rods q connected to the pivoted racks p. The cylinders a are also fitted with locking-levers b<1> provided with rollers c<1> which engage recesses a<1> in the cylinders and lock the cylinders as they move upwards over the beds out of contact with the forme. The levers b<1> are operated by means of guide rails e<1>, which are pivoted to the third arms of the rack levers p and cause the locking devices to come into action as the racks p move away from the gears n, and vice versa. In the machine shown, the slide b carries inking-rollers and the impression cylinders after moving from position A to position B corresponding to the length of the forme, move further to position C to enable the inking to be completed. The racks p are set to come into operation at position B and the cylinder is rotated while passing from B to C, and are reversed as the carriage returns from C to B. In a modification the auxiliary racks p are replaced by racks 17, Fig. 6, and rack levers 15 which are mounted so as to be capable of moving relatively to the slide b so as to start and stop the cylinders more gradually than would be the case if the racks were fixed relatively to the slide. These racks 15, 17 are connected to guide-rods 22 which are reciprocated by links 16 connected to a thrust member 27 which is reciprocated on guide-rods by a cam 32 on the shaft.of the operating crank for the bed b. The rod 22 is moved laterally so as to bring the racks 17, 15 into and out of engagement with the wheels n by means of curved slots 23 which are engaged by rollers 24 fixed to the bed. Impression rollers.-The cylinder a is made of light metal, e.g. aluminium, and for strength it is secured by bolts to flanged steel or like journals.