Patent GB-189921508-A (GB)
Title: Improvements in Rotary Printing Machines.
Inventor: BOUVET GASTON ELIE
Filed: 1899-10-27
Granted: 1900-10-27
Abstract: 21,508. Bouvet, G. E., and Fix, E. A. Oct. 27. Lithographic and like printing; rotary machines; feeding-apparatus for webs. -Relates to rotary printing-machines of the kind described in Specification No. 30,543, A.D. 1897. One form of machine is provided with three cylinders A, A', A<2>, Fig. 1. of equal diameters and geared together so as to rotate at the same speed. The cylinder A is the impression cylinder, and the cylinders A', A<2> respectively carry printing-plates Z<1>, Z', and print successively upon the paper X, so as to produce a continuous design. Two cylinders a<1>, a', Fig. 4, may be employed instead of the cylinder A, Fig. 1, and, in order to adjust the distance between the points of contact m<1>, m<2> so as to compensate for the differences of thickness of papers upon which the plates Z<1>, Z' are required to print continuous designs, the paper may be caused to travel over an adjustable bridge-piece D, Fig. 4, having terminal verticallyadjustable bearings. Any convenient means may, however, be employed for adjusting the length of the paper X between the points m<1>, m'. The rollers a<1>, a<2> may be replaced by pressers of the kind employed in ordinary lithographic machines. In other forms of printing-machines, there are three printing-cylinders which may act in conjunction with one large impression cylinder, or three smaller ones. These forms of machine may be converted into machines working with two printing- cylinders by suitably raising one of the three impression rollers, when the corresponding printing-cylinder becomes inoperative. When printing a second colour, correct register is obtained, or indicated, by means of adjustable pointed pins d, Fig. 9, carried by horizontal bars which are mounted upon endless chains d<2> travelling at the same speed as the paper X, as described in Specification No. 30,543, A.D. 1897. The rollers c, c<13>, over which the chains pass, are provided with two diametrically-opposite recesses d<3> for receiving the bars, and the rollers themselves are made of such a diameter as to allow the change, described above, from a three-cylinder to a two-cylinder machine, to be effected without affecting the efficient working of the pins d. In a further modification of the machine, the rollers corresponding with the rollers c, c<13>, Fig. 9, are each provided with one recess and serve also as impression cylinders ; in this case the bars should completely fill the recesses; or impression cylinders may be employed in addition to the rollers c, c<13>, and the paper may pass over an intermediate roller on its way from the cylinders c<13> to the first printing-cylinder. A similar arrangement may be adopted in the case of a three-cylinder machine. Metallic or other cables or ropes or endless steel bands, perforated with equidistant holes engaging the teeth of their driving bands, may be used instead of the chains. The registering-pins d may be arranged upon the ends of the arm of a star-wheel instead of being carried by horizontal bars. In another form of machine, the registering-pins are carried by bars arranged within the interior of a drum, the diameter of which equals that of the printing- cylinders, and cams may be used to press the pins outwards where the paper begins to pass over the drum. In a modification of this form of machine, the drum is mounted in contact with the first printing-cylinder and serves also as an impression cylinder.