Patent GB-639655-A (GB)
Title: Improvements in or relating to printing machines
IPC: B41L47/58
Filed: 1947-03-06
Abstract: 639,655. Addressing &c. machines; tripping-arrangements. ADDRESSOGRAPH - MULTIGRAPH CORPORATION. March 6, 1947, No. 6337. Convention date, March 19, 1946. [Class 100 (ii)] In an addressing or like machine comprising printing devices fed step-by-step, settable detectors engaged and set by tabs &c. on the printing devices, and sensing mechanism for sensing the detectors, the detectors are stationarily mounted in the machine and the printing devices are moved one by one towards the detectors to adjust the latter by means of the tabs. Feeding printing devices. Plates 31, Fig. 6, are extracted from a magazine 5 and fed first to an intermediate position and then to printing position by pawls 36 on feed bars 28 reciprocated from a main shaft 19 by means of an eccentric 22 and rods &c. 24-27. The shaft 19 is rotated through a onerevolution clutch actuated by depressing a key and through a friction clutch which slips if the mechanism jams. Impression mechanism. A platen roller which is lowered and rolled over the plate in printing position is operated from the shaft 19 through onerevolution clutch mechanism as described below. Clutch mechanism. On depressing a second key, a rod 54, Fig. 8, is pulled to the left, thereby turning a bell-crank 47 a nose 48 on which is released from a lug 43 on a pawl 39 pivoted at 40 to a cup-shaped member 20b which is then coupled to a collar 20a fixed to the shaft 19. At the end of a revolution during which the impression mechanism is operated, the lug 43 engages the nose 48 to disengage the pawl 39. In the rest position, the nose 48 may pass through a slot 44 to lock the member 20b. A shoulder 55 on a latch 51, pressed to the left by a spring 50 engages a pin 53 on the bell-crank 47 to hold the latter in the operative position, the pin 40 releasing the latch before the end of a revolution of the clutch. A similar latch is provided for a main clutch through which the shaft 19 is driven. Detectors. The tabs on the lowermost plate 31 in the magazine 5 engage fingers 70, Figs. 6, 13 and 28, mounted on a shaft 78. Each finger has a notch 71 and shoulders 84 cooperating with tabs on a master plate similar to the plate 31. The shaft 78 is carried by a bar 79, a flange 82 on which co-operates with a plate 83 to form a slot through which the tabs on the master-plate may protrude to engage the fingers 70. The latter may be restored by gravity or by means of a rocking bar actuated from a pin on the clutch through which the address-plate feed is operated. Sensing-mechanisms. The master-plate is mounted on a slide 69, Fig. 13, and is retained in position by side beads 89, front lips 90, and a vertically-slidable stop at the rear end. The slide 69 is guided on rods 86 and is actuated from the lever 25 operating the address-plate feed by a bar made in two slotted parts 102, 105 slidable on one another and connected by a latch 110 which is released from a notch 116 and snaps into a notch 117 in the event of arrest of the forward stroke of the slide 69 owing to tabs encountering detectors. Printing may be prevented from certain members of a selected group by clipping an auxiliary masterplate 185a, Fig. 28, to the main plate, tabs 188 on the auxiliary plate engaging shoulders on the fingers 70 to prevent a full stroke of the slide 69 so as to skip plates from which impressions would normally be printed. Control of impression mechanism. The slide 69 is connected to a disc.122, Fig. 18, controlling coupling of a disc 124 oscillated from the drive shaft 19 through an eccentric rod 134, with a disc 123 fixed to a shaft 125 actuating a slide 148 controlling the platen clutch 20, the mechanism providing a delay action. The disc 122 has a slot 132 which in one position of the disc allows a pawl 129 on the disc 124 to drop into a notch in the disc 123 and in the other prevents engagement. The slide 148 acts on a bell-crank 161, comprising an arm 161b carrying a pin 163 riding on a cam-flange 152 on the slide and a second arm 161a adapted to throw out the clutch 20 to prevent lowering of the platen. The arm 161a is held in either position of adjustment by a latch 166 swung clockwise in Fig. 8 by a spring 169 and released by engagement of the arm 51 with a lip 168. The slide 148 is held in either position by a latch 170, an ear 172 on which engages either of two notches 159, 160 in the flange 152. Alternative setting for printing or skipping. A slide 97, Fig. 18, can be set in the inner position shown for printing from selected address plates or in an outer position for skipping. In the inner position, a pin 163 normally engages a recess 158 in the flange 152 and the bellcrank is ineffective so that printing is effective whenever the forward movement of the master plate is obstructed. When the plate sensed has not the required tabs, however, the shaft 125 rotates, the slide 148 is moved to the left and the lever 161 disengages the clutch, thus skipping the plate. In the outward position of the slide 97, the action is reversed, the pins 163 normally resting on the part of the flange 152 to the left of the recess 158, thus disengaging the clutch for a selected plate. A plate not having a tab corresponding to the master causes the slide 148 to move to the left, the pin 163 drops into the recess 158, the clutch is released and printing takes place. A previously-made selection is preserved until the next cycle when the slide 97 is pulled out. If the latch 170 is in engagement with the notch 160, as shown, the latch 170 is sprung to one side, whereupon a spring 151 pulls the slide 148 to the extreme right retaining the latch 161 in the clutch-disengaging position, and if the latch 170 is bearing on the part of the flange between the notches, the slide 148 moves to the right until the latch drops into the notch 159 in which position the pin 163 is still in the recess 158 and the clutch is free. Specification 470,290 is referred to.