GB750902A - Improvements in rotary printing machines - Google Patents

Abstract

750,902. Rotary printing machines. TIMSONS, Ltd., and TIMSON, E. A. March 25, 1954 [March 24, 1953], No. 8090/53. Class 100 (2). A reel-fed rotary printing press wherein cooperable printing cylinders are adapted to be continuously driven and are separable by mechanism controlled by the machine attendant is provided with further mechanism, associated with the cylinder separating mechanism, for automatically interrupting a drive to web drawing rollers whenever the printing cylinders are separated. As shown, the machine includes two offset cylinders 1, 2 for printing both sides of a web of paper, two plate cylinders 3, and inking mechanism 46, 47 all of which are continuously driven from a main drive shaft which also drives gears 66, 67, 68 and 69. The offset cylinders 1, 2 are mounted in eccentric bearings and are moved away from each other and from their associated plate cylinders by gear segments 6, 7 and toggle linkage 22, 23. The mechanism for operating the toggle linkage includes' a disc 16 keyed to a transverse shaft 17 and furnished with angularly spaced blocks 20 and 20<SP>1</SP> between which is provided an arcuate space 21, the arm 22 being secured to the shaft 17. Freely mounted on the shaft 17 is a lever 25 comprising a pair of arms 25a, 25b located on opposite sides of the disc 16 and connected by pins P, P'. Upon the pin P is fulcrumed one end 27a of a rod 27, the other end of which is mounted on a crank-pin set in a spur gear 29 fast on a shaft 30, the other end of which carries a rotatably mounted gear 65 meshing with the gear 69 and which may be clutched to the shaft 30 by a clutch device 70 comprising a component 71 fast on the shaft 30 and including a spring- biased pawl 72 which co-operates with a single tooth 72 fixed in a boss 65a extending from the gear 65. The pin P<SP>1</SP> carries a double-ended pawl 31, a spring 32 normally urging the end 31a of the pawl into the space 21 for co-operation with the block 20 so that as the pawl is reciprocated by the rod 27 the shaft 17 is given a clockwise movement to throw on the cylinders 1, 2. For throwing off the cylinders there is provided a manually rotatable shaft 38 carrying an eccentric 37 which bears against a member 33 pivoted at 34 and formed with cam surfaces 33a, 33b for action upon a roller 36 on the end 31b of the pawl 31. When the eccentric is rotated to the position shown in Fig. 5, the member 33 is urged towards the pawl 31 by a spring 35 and depresses the end 31b of the pawl in the space 21 so that at the next reciprocation of the pawl 31 the shaft 17 is turned anticlockwise to throw off the cylinders 1, 2. At the same time a cam 79 inclined, or mounted for movement, with the disc 16 operates on a roller 78 on a two-armed lever 77 pivoted at F so that the lever 77 is turned clockwise to cause a presser member 74, pivoted at 75 and connected to the lever 77 by a link 76, to disengage the pawl 72 from the tooth 73, thereby stopping the shaft 30. The gear 29 meshes with a gear 64 to drive, through bevel gears 61, 62, a shaft 48 driving the web drawing rollers, so that when the shaft 30 is stopped the web drawing rollers are also stopped. If it is desired to start the web of paper running before the cylinders are thrown on the eccentric 37 is adjusted to the position when the member 33 bears against the pawl roller 36 to an extent such that neither end of the pawl is depressed into the space 21, this position of the eccentric coinciding with the point where a pin 81 mounted thereon bears on the end of a slot 82 in a link 80 so as to depress the link and rotate anti-clockwise an arm 83, turning movement of which serves to turn the fulcrum F, which is eccentrically mounted, of the two-armed lever 77. As a result, the link 76 is pushed forward to release the presser member 74. Specifications 540,112 and 750,903 are referred to.