Patent GB-127079-A (GB)
Title: Improvements in or relating to Printing Presses.
IPC: B41F3/46
Filed: 1918-04-23
Abstract: 127,079. Goss Printing Press Co., (Goss Printing Press Co.). April 23, 1918. Driving printing-machines; stopping, starting, throw-out, and like arrangements.-A multi-web printing-press is provided with electric means whereby, on the breaking of a web, the press is automatically reduced in speed and then manually brought to rest, the main driving-motor and its connected shaft continuing to run, and with means for driving the couple of the broken web from the main motor to re-thread the web. Fig. 2 is a plan of the driving-gear of the press shown in Fig. 1. The press comprises two sets of couples for printing two webs 40, 41. The couples are normally driven in unison by spur and bevelgearing from bevel-gears 29, 30 loose on a vertical shaft 31 and adapted to be normally connected thereto by clutches 34. The shaft 31 may be driven at high or low speed from the main driving-motor 42, Fig. 2, by the following gearing. A pinion 44 on the motor shaft 43 drives a gear 45 loose on a shaft 47 and connected by a sleeve 46 to a pinion 48 meshing with a gear 49 loose on a shaft 51. A pinion 58 fixed to the shaft 51 engages a gear 59 fixed to the shaft 47, and the shaft 47 is connected to the shaft 31 by bevelgears 60, 61. The gears 45, 49 are adapted to be connected to their shafts by clutches 62, 55. With the clutch 62 open and the clutch 55 closed, the press is driven at low speed, and when the clutch 62 is closed, the press is driven at high speed, the clutch 55 overrunning the gear 49. The clutches 55, 62 are actuated in sequence by grooved cams 69, 75 on a shaft 70 adapted to be operated by an auxiliary motor 80, Fig. 1. The cams are shaped so that a quarter-turn of the shaft 70 in one direction closes the clutch 55, and a further quarter-turn in the same direction closes the clutch 62. On the reverse movement of the shaft 70, the clutches 62, 55 are thrown out in succession, and on a further slight turning of the shaft, a brake band 76, Fig. 1, is tightened on to a drum 77 to bring the press to rest with the exception of the motor 42 and its connected gearing. The motor 80 is provided with a controlling- means indicated in Fig. 8. A positive main 121 is connected to a pivoted contact blade 80<g> cooperating with fixed contacts 80d, 80f connected by leads 122, 123 with the motor 80. The leads 122, 123 are connected as shown through solenoids 80<b>, 80<c> and wires 124, 125 to a commutator switch 80h on the shaft 70. This switch 80<h> is also connected bv a wire 126 to the negative main 120. The switch 80<h> comprises three bars 80<j>, 80<k>, 80<m>. With both the clutches 55, 62 open, the press is started by moving the switch blade 80<g> into contact with the contact 80<d>. The motor 80 is thereby operated to give the shaft 70 a quarter-turn, closing the clutch 55 and connecting the wires 124, 126 by the contact bar 80<m>. This excites the solenoid 80<b> to open the switch contacts 80<g>, 80<d>, and the motor 80 stops. The press runs at low speed until the contacts 80<g>. 80d are again closed by hand. The shaft 70 therebv receives a further quarter-turn to close the clutch 62, and the motor 80 is again stopped by the connexion of the wires 124, 126 by the contact bar 80<k>. When the press is to be stopped, the contacts 80<g>, 80<f> are closed and the motor is driven in the reverse direction by the current passing through the lead 123, turning the shaft 70 through half a revolution, opening the clutches 62, 55 in succession, and applying the brake 76, the motor 80 being then stopped by the opening of the switch contacts 80<g>, 80<f> through the excitation of the solenoid 80<c> by the connexion of the wires 125, 126 through the contact bar 80<j>. The leads 123, 121 are connected to wires 83, Figs. 1, 2, and 8, to which are connected switches 88 adjacent to each web, and a switch 87 adapted to be closed by the closing of the clutch 62. The switches 88 are normally open, but are adapted to be closed, on the breaking of either web, by the rise of a lever 92 carrying a roller 93 resting on the web. A pin 95 on the lever 92 co-operates with a spring-pressed pin 96 on the machine frame to prevent closing of the switch 88 by a gradual fall of the roller 93, but the pin 96 yields on a sudden fall of the roller due to breakage of the web. If a web should break during the high-speed running of the press, the corresponding switch 88 is closed and the motor is driven in a direction to disengage the clutch 62, the motor then being stopped by the automatic opening of the switch 87. The breakage of a web while the press is running at low speed has no effect on the motor 80, as the cricuit 83 is broken through the switch 87. A handwheel 98 is provided on the shaft of the motor 80 for turning the shaft 70 manually. The independent driving of either set of printing-couples for re-threading the broken web is effected by a vertical shaft 103, Figs. 1 and 2, which is driven constantly at low speed by a shaft 100. Fig. 2, driven from the pinion 48. The shaft 103 carries loose gears 105 meshing with gears 32 fixed to the bevel-gears 29, 30, and the gears 105 are adapted to be connected to the shaft 103 by clutches 107. The clutches 34, 107 are operatively connected together by levers 114, 115 so that one clutch is open while the other is closed. By moving the clutches to the position shown in Fig. 1, the couples are driven at low speed from the shaft 103. The teeth of the clutches 34 are so shaped as to allow slight slipping when the press is slowed down or brought to rest, to avoid jarring.