Patent GB-334559-A (GB)
Title: Improvements relating to printing presses
IPC: B41F3/80
Filed: 1929-03-05
Abstract: 334,559. Arnold, C., (Chandler & Price Co.). March 5, 1929. Cylinder machines; bedreciprocating apparatus; tripping - arrangements; gripper mechanism.-The bed 4, Fig. 5, of an oscillating cylinder machine is geared to the cylinder 8, and is reciprocated by means which permit of a variable throw but cause the bed always to return to the same starting position. This bed-reciprocating means is also constructed to produce a counterbalancing effect, and comprises a crank 45, Fig. 10, on a shaft 37 geared to the main driving-shaft 12, Fig. 3. The crank 45 is connected by a connecting-rod 51 to lever arms 52 on a shaft 53, which is thus oscillated by the crank, and a variable oscillating motion is transmitted from the levers 52 to a gear sector 48 on a plate 46 pivoted to a shaft 47. The gear 48 engages a pinion 49 on a shaft 50, Fig. 5, fitted with gear wheels 70, engaging racks 71 on the underside of the bed, which moves in horizontal guides. The plate 46 moves to the left as the bed moves to the right, and so the counterbalancing is obtained. To vary the extent of oscillation of the gear 48, the levers 52 are pivoted to a forked link 54 pivoted to a block 55 which can be adjusted in a curved slot 56 in the plate 46 by means of a screw 58 operated by bevel-gearing from a hand-wheel. The screw 58 engages a nut pivoted to the block 55, and causes it to move in the slot 56, which is concentric to the pivot between the members 52, 54. Adjustment of the block 55 thus varies the extent of oscillation of the plate 46, but the starting point of the bed and of the cylinder 8 is constant. The shaft 12, Fig. 3, is driven by a motor 13 carried by a cradle which is adjustable to vary the tension of the driving-belt, and the drive is transmitted through a friction clutch controlled by lever mechanism from a hand lever 24, Fig. 1, fitted with a pawl engaged by a segmental ratchet 25. The cylinder at each end is mounted in eccentric bushings 77, Fig. 8, fitted in boxes 10 mounted above extensions 7 of the side walls 1 of the machine frame, and the bushings 77 are oscillated by lever mechanism from a cam 90 on shaft 37. A notched link 93 forming part of this mechanism is held by a catch 215 controlled by feeler mechanism, and the cylinder is held out of printing position if a sheet is not fed correctly. The feeler 225, Fig. 17, is adapted to engage a notched guide plate 228 if a sheet is missing. This feeler is oscillated by a lever 224 and link 223, and if a sheet is present a notched link 222 is permitted to fall and engage a pin 220 on a lever arm 219 on the shaft 53. The catch 215 is connected by a link 218 to the lever 219 and normally permits operation of the cylinder lowering means. If no sheet is present the link 218 remains raised and the catch 215 prevents this operation. The sheetcontrolled tripping means may actuate a shroud plate associated with the segmental ratchet 25, and cause the drive to be stopped and a brake 26 applied when a sheet is not fed. Normally the cylinder 8 is raised out of action on the return of the bed, but the cylinder remains in gear with the bed and is reversed for the delivery motion of the sheet as the bed returns. The automatically fed sheets are seized by spring-controlled grippers 81, Fig. 8, on the cylinder 8, the grippers being controlled by a lever arm and a cam 87, Fig. 1, which can be turned about a pivot 100 to give the grippers a positive opening movement at the sheet receiving and delivery positions. To effect this, the cam 87 is connected by lever-and-link mechanism 101, 102, 103, to a shaft 104 oscillated by cam mechanism from the shaft 37. Inking-apparatus.-The forme is inked by rollers 123, Fig. 1, driven by a gear engaged by a rack on the bed, and supplied from a duct roller 118 by an oscillating messenger roller 119 fitted with a steel rider roller 119<a>, and operated by lever mechanism from a link 130 which is reciprocated by the oscillating shaft 53. Rider and distributing rollers 121, 120 transfer the ink from the roller 119 to the rollers 123. The duct roller 118 is rotated intermittently by ratchet mechanism, and can be rotated independently by a handle. The inking-apparatus is mounted in a frame 110 supported by two sets of parallel links 111, 114 which enable the frame to be moved over the impression cylinder and away from the bed, after the sheet-delivery conveyor has been moved to inoperative position. Access to the bed for insertion of new formes is thus facilitated.