GB572659A - Improvements in web splicing - Google Patents

Abstract

572,659. Feeding webs. WOOD NEWSPAPER MACHINERY CORPORATION. April 17, 1944, No. 7091. Convention date, April 14, 1943. [Class 100 (i)] [Also in Group XL] In a web-renewing mechanism the leading end of a new roll is spliced to the running web by means controlled by marks adapted to actuate in connection with photo-electric cells, or electric switches to bring into action websevering mechanism, and in some cases webpasting mechanism. The marks may be on the running web and the web roll, and in some cases on the web roll only, the pasting mechanism being controlled by hand-operation. As applied to a mechanism in which the join is effected by self-sticking adhesives of the kind described in Specification 555,707 applied to the edge of a web roll and applied to the core end of an expiring web in a position indicated by 33, Fig. 1, and Fig. 3 the length of the adhesive 33 being greater than the circmnference of the new roll 14. A dark area 35 is arranged near the end of the expiring web in a gap 34 in the area 33, the front edge of the mark 35 being in rear of the front of area 33 by an amount equal to the distance of a scanning device D from a roller 47 which is mounted on a pivoted frame 45 moved to bring the expiring web into contact with the new roll when the running web roll 16 is nearly expired. The device D is shown in Fig. 4 and comprises a source of light 38, a lens 39, windows 40, 41 and a cell 42 which normally receives enough reflected light to energize a magnetic relay 43 which maintains a switch 44 open. When the dark mark cuts off the light, the switch 44 is closed, and at the same time a second scanning device D<1> operates under control of a mark 36 on the web roll and causes another switch to close so that an electromagnet 50 is energized to actuate a cutting device 49 for severing the old web. A band 19 assists to bring the speed of the roll 14 to that of the expiring web. As applied to a web-joining device in which ordinary paste is secured to the leading. end of the new web and the old web is provided with a control mark as in Fig. 1, a pasting-brush 73, Fig. 6, is actuated by an electromagnet 75 under control of a scanning device S <1>, and a second scanning device S controls an electromagnet 77 which operates the knife 74. In a modification of this device, the magnet 75 may be controlled by a hand-operated switch, and the cut-off switch operated by a mark on the roll and a scanning device. The marks instead of acting by light control may be marks of conducting material actuating electric switch contacts.