GB588057A - Improvements in or relating to inking mechanism for rotary intaglio printing presses - Google Patents

Abstract

588,057. Inking mechanism. GOSS PRINTING PRESS CO., Ltd. Jan. 12, 1945, No. 1053. Convention date, Jan. 14, 1944. [Class 100 (ii)] [Also in Group XXIX] In inking mechanism for a rotary intaglio printing-machine, a fluid-pressure cylinder is employed for reciprocating the doctor blade the supply of pressure fluid to the cylinder being controlled by a pilot valve the operation of which may be controlled to vary the rate and extent of the movement of the blade. As shown in Fig. 3, the doctor blade carrier 73 is connected to a piston 100 in a cylinder 101, the other side of the piston being adjustably attached by rods 118 and 203 to a lever 205 which is fulcrummed at 213 in a block 214 adjustable vertically by a screw 216, and has its lower end connected by a link 210 and rod 144 to a slidable barrel portion 143, Fig. 4, of a pilot valve 120 which controls the flow of pressure fluid to the cylinder 101. Fig. 4 shows a modification of the connections from the piston 100 to the rod 144, the lever 205 and the rods 203, 210 being replaced by a lever 170. The barrel 143 has two ports 168, 169 in permanent connection with two outlet ports 160, 165 connected by conduits 109, 108 to the opposite ends of the cylinder 101. The ports 168, 169 are controlled by plungers 132, 133 on a shaft 134 having a cam follower 138 held in contact with an edge cam 140 by a spring 141. The cam is mounted in a shaft 191 driven at an adjustable speed by a belt and expanding pulley mechanism 192, 193. The cam 140 may be a box cam in which case the spring 141 is dispensed with. When the shaft 134 is moved to the right, oil or other pressure fluid from a pump 181 passes through conduit 128, pressure chamber 151 between the plungers 132, 133, port 165, and conduit 108 to the left hand side of the piston 100. The movement of the piston to the right causes the barrel 143 also to move to the right and close the port 165. At the same time oil on the right hand side of the piston 100 exhausts through the conduit 109 and the port 160 into the chamber 176, connected to a sump. The cam now allows the spring 141 to move the plungers 132, 133 to the left and the pressure chamber 151 is opened to the port 160 and thus to the right hand side of the piston 100, moving it to the left, whilst the port 165 is opened to the right-hand end of the barrel 143 and the return oil can flow through holes 178 in the end of the barrel 143 into the return chamber 175 also connected to the sump. By suitable choice of the shape of the cam, the speed of the doctor blade and its acceleration and retardation at the beginning and end of its strokes may be varied as desired. The length of the stroke may be varied by adjustment of the fulcrum 213 and of the points of connection of the rods 203, 210 to the lever 205.