Patent GB-191306881-A (GB)
Title: Improvements in Cylinder Printing Machines.
Inventor: JOHNSTON THOMAS RUDDIMAN
IPC: B41F3/42
Filed: 1913-03-20
Granted: 1913-12-04
Abstract: 6881. Johnston, T. R. March 20. Gripper mechanism; cylinder machines; rotary machines; printing in several colours; offset machines. - The grippers c1, Fig. 3, in a multicolour cylinder printing-machine of the two - revolution, stopcylinder, lithographic, or off-set type, or in a rotary machine, are attached to the links of a chain c2 running over wheels c3, c4, at each end of the impression cylinder b1, and provided with gripperclosing devices, Fig. 11, and opening - devices, Fig. 9, and intermittently-operating chainfeeding devices, Fig. 6. In operation, a small sheet j3 is fed to one end of the cylinder b1, and, after being printed in one colour, is moved by its grippers laterally along the cylinder to the position j2 to be printed in a second colour while a fresh sheet taken by other grippers in the position j3 is printed in the first colour. If desired, the sheet is then printed in further colours, as at j1, and finally the grippers are opened, and the sheet passed to the delivery at g1. The chain c2 is kept tight by springs c21 acting on the bearings of the chain-wheel c4. The chain-wheel c3 is geared to the wheel h1 running loose on the impression cylinder shaft b3, and having on one side a notched disk h4, Fig. 6. Normally, a sliding spring-pressed catch h9 on the cylinder b1 engages one of the notches h5, h6, h7, h8, and prevents the wheel h1 from moving relatively to the cylinder b1. When it is desired to shift the chain c2, a cam h18 on a slide h12 is brought into position to engage a runner h19 on the catch or bolt h9, thus releasing the wheel h1. At the same time, a finger h13 on the slide h12 engages a runner h15 on the wheel h1, gradually slows it down, and then accelerates it until it is in the position h14. Meanwhile the bolt h9 will have travelled through one half-revolution, and will drop into the notch h5, which will then have travelled through one quarter-revolution. The slide h12, which works in a slide m1, is then lowered, returned to its right-hand position, and raised to repeat its operation, the movements of the slides h12, m1 being obtained through cams and adjustable links. For stop-cylinder machines, a similar mechanism is used, but the finger h13 pushes the wheel h1 round one quarter-revolution while the cylinder is at rest. The grippers each comprise a fixed part c6 attached to a link c2 of the chain, and a hinged part c8 controlled by a spring c10 to remain either open, at the position c9, or closed. A block c15, fixed to the other side of the link, engages a slide c16 so long as the gripper is on the working side of the chain run, and holds it steady. The jaw c8 has a tail piece c12 by which it is operated. When a sheet j3 is to be taken from the feedboard f1, the particular set of grippers c1 that remain open from the delivery of the last sheet, are closed as follows. A stop e10, adjustably mounted on a bracket e22 fixed to the framework a2, lifts a catch e5 and releases a lever e4 on the shaft e1, which is then turned by a spring e7 so that levers e2 fixed on the shaft engage the tail-pieces c12 and close the grippers. A second stop e15, shown in its right position in Fig. 3, acts on the arm e16 to reset the shaft e1. Similar devices, Fig. 9, are used at the other end of the cylinder b1 to open the grippers, an adjustable stop d10 releasing the catch d4, and allowing the shaft d1 to turn and open the grippers c8, by means of arms d11, after which the shaft is reset by the stop d10 engaging a lever d15, acting on the arm d14 on the shaft. Before the sheet is taken by the grippers, it is registered against front stops f5 and side lays f6. A holding-bar f4 is then lowered by levers f8, f7, f10 to grip the paper lightly to the table f1, which itself is then lowered to present the front edge of the sheet to the grippers. The sheets are delivered by grippers on a bar carried by chains g8 driven by suitable gearing from the cylinder b1. Specification 11,009/88, [Class 101, Printing other than letterpress &c.], is referred to.