Patent GB-229323-A (GB)
Title: Improvements in cylinder printing machines
IPC: B41F3/40
Filed: 1925-02-13
Abstract: 229,323. Fallot, A. Feb. 14, 1924, [Convention date]. Cylinder machines.- A cylinder machine for printing on webs for magazines, newspapers &c., is constructed with a pair of oppositelyarranged vertical-type formes a for each web to be printed, and s reciprocating carriage e, which moves ver. tically up and down between the formes and is fitted with two impression cylinders f around which the web from a roll m is threaded is such a manner that the cylinders print impressions on the opposite sides of the web on the downward strokes of the carriage e, the cylinders being held from rotation on the upward strokes. The machine shown perfects two webs which are finally associated and folded by a longitudinal folder 12, and the two carriages e are driven by crank-discs h geared to a shaft o driven by a motor. The one carriage e descends as the other ascends, so as to balance the forces, but three carriages may be used, in which case the crank-pins are arranged at intervals of 120‹. The webs are fed in and out by constantly-driven feed rolls n, n<1>, and, to allow for the intermittent feed by the cylinders, looping-rollers k, k<1> are reciprocated to take up the slack in the web when necessary. The rollers k are reciprocated by eccentrics on the shaft o. The cylinders f are fitted with gear wheels which engage fixed vertical racks b in the machine frames, the wheels driving the impression cylinders through one-way clutches. The cylinders are held from rotating on the upward motion of the carriages by camoperated band-brakes, or by means of spring- pressed detents l, Fig. 1<a>, which are actuated to release the cylinders by spring-pressed bars l<2> acting on rollers l<3> on the detents, the bars l<2> being moved by springs l<4> into operative position when permitted by bell-cranks q controlled by a cam-operated lever p. Printing-surfaces; tripping-arrangements.-The type frames a, Fig. 2, are inserted through side openings in one side of the machine frame, the racks b being raised by gear-wheels c while the frames a<1> are inserted. The frames a<1> are secured to the beds d by means of dovetailed holders d' slidably mounted in the beds engaging undercut grooves at the backs of the frames, and screw-actuated wedge rails d<2>. The beds are supported at their corners on rotatable threaded pins d<4> simultaneously adjustable by bevel wheels and spindles d<5>. Inking-apparatus. - The formes are inked by rollers g fitted on the carriages e above and below the cylinders f, and receiving ink from bands r, which serve as ink-tables, and are supplied from ducts v by messenger rollers t. In a modified form the ink-applying rollers g are carried only on the bottoms of the carriages e and in this case the extent of the reciprocating movements of the carriages is increased beyond the normal, namely the length of the type forme, or the circumference of the cylinder f. In this case, to prevent the cylinders f from rotating more than one complete revolution for each reciprocation of the carriage e. the racks which drive the gear wheels on the cylinders f are formed with spring-pressed movable portions which move with the carriages after they have been raised a distance equal to the length of the printing forme. The rotations of the cylinders on the downward strokes is thus delayed until the spring-pressed racks return to their normal positions, and the impressions are formed on the webs with the correct intervals between the same. Alternatively, the racks may be movable and actuated by eccentrics to prevent relative motion between the cvlinders and the racks for the intervals in which it is required to prevent rotation of the cylinders.