GB572625A - Improvements in web winding - Google Patents

Abstract

<PICT:0572625/IV/1> <PICT:0572625/IV/2> <PICT:0572625/IV/3> In apparatus for winding webs continuously into rolls, the transfer of the web 9, Fig. 1, from a full core 26 to the core 25 of a new roll is effected by the aid of controlling marks 54 on the web which actuate light-sensitive or other control devices for causing actuation of a knife 67 which severs the web going to the full roll and directs the leading end of the cut web to the core 25. The control devices may be relays actuated by the marks 54 on the web and also by marks 80 on the outside of a short length of web 26, Fig. 2, which is wound on the core prior to its being mounted in the arms 19 of the roll support, there being three sets of arms 19, 20, 21, each fitted with adjustable bands 37, 38, 39. The main driving-bands 28 are passed over rollers 14, 15, 16, 31, 32, 33, driven by a motor 34 and tensioned by the weighted roller 32. As shown in Fig. 1, there are two scanning devices D, D1 which cause energization of an electromagnet 73 which releases the springcontrolled cutting-device 67 when the marks 54 are printed on a master web, led from a roll to or coming from the calenders of a papermaking machine, by means of a printing-roller 58 and an impression roller 59 which is brought into operation by an electromagnet 62 on operation of a switch 64. The switch is operated when the roll 26 is full, and an electromagnet 63 is operated at the same time to operate a valve 56, which causes compressed air to spray an adhesive material from a reservoir 49 to produce an area 61, Fig. 4, of a self-sticking adhesive of the kind described in Specification 555,707, [Group XVI]. A shield causes a gap in the area 61 at the position occupied by the mark 54 which is arranged in advance of the area 61 by a length equal to the distance between the roll 25 and the scanning-device D. The roll 25, Fig. 2, is wound with a web 76 coated on the inside with a self-sticking adhesive adapted for use in joining up a new roll to the expiring web of an old roll when the rolls are used in a printing &c. machine. A layer 79 of this adhesive is applied to the front edge of the web 76, which is secured by tabs 78. The core 25 is driven at the same speed as the web prior to the severing of the web and the starting of the winding of a new roll which occurs when the adhesive area 61 becomes attached to the layer 79. In place of light-sensitive scanning devices, there may be employed electric contacts engaging conducting marks 54 used in place of colour marks. The mark on the core member may be dispensed with and only one conducting area used.