GB743377A - Improvements in rotary sheet-printing machines for letter press printing - Google Patents

Abstract

743,377. Rotary printing-machines. VEB DRUCKMASCHINENWERK VICTORIA VVB POLYGRAPH. Sept. 28, 1953, No. 26607/53. Class 100 (2). In a rotary letterpress machine in which the forme cylinder can readily be replaced by another, the forme cylinder 9 is housed in bearings which are withdrawable axially, rail supports in the frame then support the cylinder, the supports are lowered so that the cylinder can run out of the frame on runways, and a trolley provided with rails receives the cylinder for conveyance away from the machine. A fresh cylinder is then placed on the trolley and positioned in the machine. The cylinder 9, Fig. 3, has tapered barrel-type journals 21, 20 housed in tapered bearings 23, 24, respectively, which are slidable axially in housings by means of spindles 25, 26. Each spindle has screw-thread engagement with a bearing, and is rotated by means of a handle 28 which can be locked by ratchet and pawl means. When the bearings 23, 24 are withdrawn axially, forked rails 30 engage peripheral grooves 22 in the journals and support the cylinder 9. The rails 30 are secured to inclined racks engaged by gears 32 on a shaft 33, the latter being rotatable by gearing 35, 37 operated by a hand-crank 38, whereby the racks, supporting the cylinder, are lowered to such a position that the cylinder can be rolled out of the frame 1 along fixed rails 43 secured to the frame. The cylinder 9 is received by a trolley or carriage comprising a lower part 46 with wheels 45, and an upper part 48 with wheels 49 arranged to run on rails on the lower part 46. The trolley is moved up to the machine and the lower part 46 latched to the frame 1; the upper part 48 is moved along the rails on the lower part and then into the machine on fixed rails arranged on the frame 1 in a gap between the printing couple and the delivery apparatus 7. Folding rails 54 on the upper part 48 are then lowered and located in the frame 1 to form a continuation of the fixed rails 43, so that the cylinder 9 can be rolled on to the upper part 48 and then conveyed away by the trolley. This procedure is reversed when the new cylinder 9 is introduced into the machine. When the bearings 23, 24 are moved into position over the journals 21, 20, pins 40 on the bearings enter holes 39 in the rails 30 to prevent the latter being lowered during operation of the machine.