GB823207A - Improvements in web-renewing mechanism - Google Patents

Abstract

823,207. Feeding webs. CRABTREE & SONS Ltd., R. W. Feb. 24, 1956 [Feb. 25, 1955], No. 5786/55. Class 100(1) In a web renewing apparatus which includes means to time the transfer of web supply from a running web to the web of a rotating replacement roll, the timing means is arranged to respond initially to the diameter of the running roll and when that roll is reduced to a predetermined diameter to change-over to respond to a linear measurement related to the length of web drawn from the roll, the apparatus including a device to initiate a web renewing operation and the timing means being arranged to render the device active when a predetermined linear measurement is made. As shown, a roll spider has pairs of arms 1, 2, 3 carrying rolls 5, 6, 7, the roll 5 being an expiring roll, the roll 6 a replacement roll, and the roll 7 a newly loaded roll. The roll 5 engages belts 8 driven through a pulley 9 by the machine being fed. A belt frame 12 carrying a pulley 11 swings about the axis of a pulley 10 to follow the decrease in diameter of the roll 5. When the roll 5 has been reduced to a predetermined diameter a lever 16 mounted on a shaft 17 rocks the shaft 17 to actuate a striker 30 on a trip arm 29, thus releasing a latch 27 which normally holds a roller 20 out of engagement with a roller 24. The roller 20 is pressed into engagement with the roller 24 by a spring 32, an arm 23 which supports one end of the roller 20 carries a control arm 39 which upon engagement of the rollers 20, 24, actuates a switch 40. Actuation of the switch 40 causes rotation of the roll spider about a shaft 4 to bring the replacement roll 6 into renewing position at a distance from the running web W predetermined by a limit switch, not shown. The actuation of the switch 40 also causes lowering of the belt frame 12 and positioning of a brush and knife assembly 15 .adjacent the web W. Rotation of the roller 20, effects through epicyclic gearing, not shown, within the roller 20, engagement of a second control arm 38 with a switch 41 after a predetermined length has been unwound from the roll subsequent to the actuation of the switch 40. The second switch 41 causes actuation of a brush 13 which deflects the web W into engagement with the roll 6 to splice the two webs together and then causes operation of a knife 14 to sever the web W. The assembly 15 is then returned by gearing 44, 45, 46 to its inoperative position, thereby causing a cam 47 on the gear 46 to actuate an arm 48 secured to the shaft 17 to move the roller 20 apart from the roller 24. Specifications 453,112, 478,578 and 616,162 are referred to.