GB280272A - Improvements in or relating to web renewing and supplying mechanism for printing presses - Google Patents

Abstract

280,272. Goss Printing Press Co. of England, Ltd., and Smith, E. J. Aug. 9, 1926. Feeding webs. - In webrenewing mechanism for a printing-press of the kind described in Specifications 260, 049 and 265,667 and having a pair of pressure rollers for use in uniting the reserve and active webs, the pressure rollers have independent operating-means so arranged that either pressure roller, having the reserve web attached thereto, can be moved into contact with the other pressure roller, this being rotated by the active web; the operating means is adapted to start an endless belt or the like for driving the reserve web, and automatic or manual speed-control devices for the endless belts are provided. In the mechanism shown in Fig. 3, the pressure rollers B are carried by arms C on shafts D provided with hand-levers E for moving either pressure roller into contact with the other. Each pressure roller is equipped with a gripper F which is mounted on a shaft F<1> and normally forms part of the surface of the roller. An arm F<2> on the shaft engages a spring F<3> adapted to retain the gripper either in normal or raised position. The leading end ot the reserve web is secured to the associated pressure roller by means of the gripper and adhesive is applied, the arm C being temporarily locked by means of a pin. The hand-lever is then depressed to bring the reserve web into contact with the active web passing over the other pressure roller. The reserve web adheres to and is carried forward by the active web, and! the gripper is automatically released by engagement of a roller F<1> on the arm F<2> with a cam on an arm C<1>, whereupon the gripper is restored to normal position by the spring F<3>. The arm C' is secured to a pin C<2> mounted on the arm C, a spring C<4> normally holding the arm C<1> out of the path of the roller F<4>. When the hand-lever is depressed, a stop G on the frame engages a second arm C<3> on the pin C<2> and causes the arm C' to move into the path of the roller. The paper rolls engage endless belts driven by shafts H<1>, Fig. 7, provided with fast and loose clutch-members I, M, the members L being connected by chains K<1> to sprocket-wheels K driven by a shaft J, and the members M being movable axially by the handlevers E. For this purpose each member M is connected by a rod N<4>, Figs. 7 and 8, to a bellcrank which is connected by a rod N<2>, Fig. 3, to an arm N<1> secured to a lever N in the path of the associated hand-lever. When the handlever associated with the reserve web is depressed, the associated shaft H<1> is started and the reserve web is driven by the endless belt. The other hand-lever is then raised to arrest the endless belt associated with the exhaust web. To prevent shock, spring are arranged between the rods N<2> and bell-cranks. The springs ensure engagement of the clutch-members before the pressure rollers are brought into contact. To provide for automatic or manual speed-control, the sprockets K are driven by means of differential gearing comprising a casing I carrying bevel-wheels I, I<1> engaging fast and loose bevel-wheels I<2>, I<3> on the shaft I' of the sproket-wheels, the bevelwheel I<3> being driven from a shaft J by means of bevel gearing J<1>, J<2> The casing I is geared to a spring-pressed friction-disc, R<1> engaging a friction-wheel R<2> which is mounted on the shaft J and can be moved across the disc by means of a forked lever R<4> having a sector R<5> engaging a worm R<6> which is manually or automatically operated to vary the speed. In a modification, the shaft J drives the differential casing by gearing comprising a belt passing round expanding pulleys which are adjustable to vary the speed. In some, cases each shaft H<1> may be provided with a differential gear associated with a brake or clutch for starting and controlling the speed of the shaft.