Patent GB-402447-A (GB)
Title: Improvements in or relating to web renewing mechanism for printing presses
IPC: B65H19/18
Filed: 1932-05-31
Abstract: 402,447. Feeding webs. TRIGGS, W. W., 57, Lincoln's Inn Fields, London.- (Wood Newspaper Machinery Corporation; 501, 5th Avenue, New York, U.S.A.) May 31, 1932, No. 15410. [Class 100 (i).] In a web-renewing mechanism for a printing machine, the fresh roll is rotated, prior to the pasting operation, by driving means applied to the roll spindle and driven from the press through a variable speed gear adjusted automatically by means engaging the roll surface so that the surface speed of the roll is substantially equal to the speed of the running web. When the join is to be made, a pivoted frame carrying a brush is lowered into proximity to the running web, the fresh roll is brought into rotation and then moved into position closely adjacent the web, the brush is operated to press the web against the new roll, the old web is severed, the new roll moved into running position, the brush frame raised, and a device at the delivery end of the press is caused to displace the products containing the doubled thickness of web. The running roll M, Fig. 1, and spare rolls L, N are carried by three-armed frames 115 rotatable in a stand and driven by an electric motor to bring the rolls successively into the running position. Normal running tension is applied to the active roll by belts 2 and the web W runs to the press over guide rollers 10, 11, 12 and a driven roller 13. The frame 15, Figs. 1 and 20, carrying the brush 51 and the severing knife 73 is pivoted upon a shaft 16 and isadapted to be lowered and raised by an electric motor 22 which, through gearing and crank mechanism operates arms loose upon the shaft 16 and connected to the frame 15 by safety shearing pins. During the lowering of the frame 15, the new roll L is set into rotation by the following means. Each roll spindle is provided with a loose gear which is continuously driven by a gear 113, Fig. 1, driven from the press through a vertical shaft 107 and a variable speed gear 100. The loose gear is adapted to be connected to its shaft by a magnetic clutch the circuit to which includes a switch in a multiple switch 233 driven by the motor 22, and a rheostat 235 also driven by the motor 22, the rheostat causing a gradual increase of the voltage supplied to the clutch. The variable speed gear 100 is adjusted automatically in accordance with the diameter of the roll by means of a roller 139, Fig. 27, carried by a pivoted arm 137 which is connected through arm 135, rod 130, sleeve 128 mounted freely between springs 131, 132 on the rod 130, bell-crank lever 126, link 124, and arm 122 to the speed adjusting shaft 121 of the variable speed gear. The arm 137 is held in its raised position by pawls 141 engaging a ratchet sector 140 on the arm. As the frame 115 rotates to bring the new roll into position, a projection 147 on the frame engages a roller 148 thereby, through connections 145, 144, 143, releasing the pawls to allow the roller 139 to drop on to the roll. Continued movement of the frame 115 then causes the roll to raise the roller 139 to an extent depending upon the size of the roll and set the variable speed gear accordingly. When the frame 15 is fully lowered a shaft 84, Fig. 21, carried thereby is moved to the left in that figure to bring a member 81 on an arm 82 fixed to the shaft in between the expiring web and the new roll and, by the closure of a switch in the multiple switch 233, the motor for rotating the frame 115 is started to move the new roll towards the expiring web. This movement continues until the roll, by engaging the member 81, rocks the shaft 84 to release it from a holding device and allow it to be moved to the right by a spring 87 to move the member 81 clear of the roll and to operate a switch 95 to stop the operation of the motor rotating the frame 115. The device for holding the shaft 84 against the action of the spring 87 comprises a collar 85 having projections to engage the ends of a sleeve 86 loose upon the rod 84 but held stationary thereon. The resetting of the rod 84 angularly is effected by moving the sleeve 86 to the right clear of the collar 85 which is then turned by a spring 88 to engage the ends of the sleeve and this movement of the sleeve is effected by a spring on the shaft 154 soon after the frame 15 begins to move upwardly to its inoperative position. The movement of the sleeve to the left to reset the rod 84 longitudinally is effected by a positive rotation of the shaft 154 by the motor 22. When the new roll is in the position just described a further switch in the multiple switch 233 is opened to stop the motor 22. The brush 51, Fig. 20, is carried by a shaft 53 pivoted in the frame 15 and is held against the action of springs tending to press it towards the web by a latch 63 connected to the armature of a solenoid 65. The solenoid may be controlled to release the brush by a push button switch or, as shown in Fig. 34, by a switch 214 actuated automatically when the expiring roll reaches a predetermined diameter. The switch 214 is carried by an arm 210 fixed to a shaft 202 to which is also fixed an arm 209 adjustable by a screw 205. A feeler 219 engaging the end of the roll is carried by an arm 218 pivoted to the arm 210 and having a depending arm 216 engaging the switch operating roller 215 to hold the switch normally open. When the roll is sufficiently exhausted, the feeler 219 moves inwardly carrying the arm 216 clear of the roller 215 and allowing the switch to close. The circuit is completed when a short contact segment on the roll spindle engages a co-operating brush contact, this segment being provided to ensure correct angular position of the roll when the brush is released. The same circuit also actuates a solenoid 177, Figs. 31 and 44, to allow the operation of a one-revolution switch 165 which effects the release of the severing knife, the starting of the motor 22 to raise the brush frame, and the operation of the device for displacing the spoiled papers on the delivery. The switch 165 comprises a drum provided with contact rings 166-169 of which 169 is the current supply ring connected to short segments on the rings 167, 168 and to a V-shaped segment 166a on the ring 166. The drum is secured to a disc 164 in engagement with a friction disc 162 constantly driven from the press by gearing 159, 160, but the disc 164 is normally held against rotation by the engagement of a pin 174 thereon with the plunger 175 of the solenoid 177. When the solenoid 177 is actuated the disc 164 is released and the switch makes one complete revolution. The segment of the ring 168 through its contact 178 closes a circuit to actuate the solenoid 77, Fig. 20, to release the knife 73 which is then turned by a spring into contact with the expiring web. As the knife turns, a cam 182a on its shaft 57 operates a switch 181 to close a circuit to a solenoid thereby allowing a normally inactive spring to apply a band brake to the spindle of the expiring roll. The V-shaped segment 166a and its contact 178 close a circuit to a solenoid 224a, Fig. 36, which thereupon rocks a shaft 220 to depress an arm 226 carried thereby into the path of the papers being delivered by the flyer to displace the spoiled papers. The time and duration of the operation of the arm 226 is regulated by angular and longitudinal adjustment of the contact 178 on the contact ring 166. A signal lamp is arranged in the circuit of the solenoid 224a to indicate that spoiled papers are being delivered. The segment of the ring 167 through its co-operating contact 178 closes a circuit to the motor 22 to start the movement of the frame 15 back to its inoperative position. During the raising of the frame a cam-actuated rod thereon effects the resetting of the brush and knife, and, as stated above, the rod 84 is reset angularly thereby allowing the switch 95 to re-close the circuit of the motor driving the frame 115. The frame is thus rotated to carry the new roll into contact with the braking belts 2 until a cam on the frame 115 operates a limit switch on the fixed frame of the machine to open the circuit of the motor. During this movement of the new roll the pressure of the braking belts gradually increases but at the same time the rheostat 235 applies a decreasing voltage to the magnetic clutch on the roll spindle so that no undue strain is placed upon the web. Safety switches are provided adapted to be actuated by cams on the roll frame 115 to prevent lowering of the brush frame 15 until the new roll is in correct position and to prevent reverse rotation of the roll frame while the brush frame is in its lower position. Power is applied to the magnetic clutch of a roll in normal running position so as to act as an emergency brake upon stoppage of the press by means of an additional circuit in parallel with the circuit for applying the brakes to the press cylinders, but this additional circuit is interrupted when a now roll is in position for the web-renewing operation and the running roll is nearly exhausted. The brush 15 is formed in sections, one section for each page width of the roll, and each section is provided with its own spring for pressing the brush against the roll. One or more of these springs may be rendered inoperative if rolls less than full width are employed.