GB939835A - Improvements in or relating to web splicing - Google Patents

Abstract

939,835. Feeding webs; splicing. A. B. DICK CO. March 14, 1962 [March 24, 1961], No. 9814/62. Class 100 (1). Apparatus for splicing web being fed continuously through a high-speed facsimile printer comprises braking means for stopping the old web, cutting means for severing the old web, splicing means for pressing the leading end of the new web against the severed trailing end of the old web with a self-sticking adhesive element therebetween and trimming means for trimming away the end portions of said adhesive element from said web. The printer 34 is used in a label printing machine 20, Fig. 1 (not shown), the unreeling and splicing apparatus of which is shown in Fig. 5, and the reeling apparatus of which is described in Specification 939,836. Unreeling, tensioning.-The web 22 running from a reel 26a passes through a splicer 28 and a loop storage elevator 30 before entering the printer. A roller 56a on an arm 54a senses the diameter of the reel 26a and automatically regulates the braking effort on the spindle 50a to maintain a substantially uniform tension in the web in a known manner. The braking effort may also be regulated by the position of the moving rollers 66 in the elevator 30. A replacement reel 26b mounted on a rotatable indexing wheel 48 of a reel stand 24 has its web 22b threaded over a roller 52b and held in readiness for splicing. Splicing. In preparation for the splicing operation, the leading end of the web 22b is trimmed square with a trimming device 86 comprising a vertical plate 88, Fig. 10, against which the web 22b is placed. Upper and lower guide bars 90, 92 locate the edges of the web 22b which is pressed against the plate 88 by a spring loaded arm 94. A knife 102 mounted on a spring-balanced, pivoted arm 104 co-operate with a stationary knife 100. A piece of doublesided adhesive tape 80, Fig. 12, is applied to the underside of trimmed web 22b. Attached to a slider 170, forming part of the splicer 28, is a punch 82, Figs. 8 and 9, having two separate cutting portions 182a, 182b. Resiliently mounted on the punch is a presser pad 78. The punch 82 is pivoted to the slider 170 at 184, and can be locked in the horizontal position, Fig. 8, or the vertical position, Fig. 9, by a plunger or bolt 186 co-operating with a hole 188 in the slider 170 or a latching slot 194 in a stationary member 196. The web 22b is attached to the cutting portions of the punch 82, Figs. 10 and 12, by the overhanging portions of the adhesive tape 80. The running web 22 passes over a flat guide or bed 72 in the splicer 28. When the diameter of the reel 26a reaches a predetermined value, a clamping bar 74 resiliently mounted to a second slider 116 clamps the web 22 against the bed 72. This is achieved through a solenoidoperated one-revolution clutch 144, Fig. 7 (not shown) driving a cam-shaft 142 and a cam 138. Shortly after the web 22 is clamped, it is cut off by one of four knife blades 160, which is rotated through 90 degrees while the cam-shaft 142 is rotated through 360 degrees. A second cam 178 operates a lever 176 and thereby moves the slider 170 downwardly. The presser pad 78 moves downwardly with the punch 82 and presses the new web 22b against the old web 22 forming the splice. The punch trims the overhanging portions of the adhesive tape 80 giving the finished splice as shown in Fig. 13. The wheel 48 is then indexed through 180 degrees in the clockwise direction, to bring the new reel 26b to the uppermost position. On completion of one revolution of the cam 138, the web 22 is released, and the new web 22b is fed into the printer of the machine.