GB892516A - Web-slitting apparatus - Google Patents

Abstract

892,516. Slitting machines. POLYMARK Ltd. March 7, 1960 [March 17, 1959], No. 9182/59. Class 31 (1). [Also in Groups XI and XVI] In a machine comprising one or more rotatable heated cutter discs 14 for slitting a travelling fabric web 11 into tapes 17, the disc or discs are of annular form and heated adjacent their peripheries by induction from an electric current passing through loops of a heating coil 16. The web preferably consists at least in part of thermoplastic yarns. The cutter discs are supported on a water-cooled shaft 15, Fig. 1, by means of ceramic spacer sleeves 82. The web passes from a reel 31, Fig. 2, over guide rollers 32, 34, through an edge guide 35, over a roller 36 driven from a main drive motor 40 and then to a row of ceramic counter rollers 12 movable into contact with the cutter discs. After leaving the cutting zone, the slit tapes 17 are engaged by comb members 20 which penetrate between adjacent tapes 17. The tapes are then displaced alternately upwardly and downwardly, to prevent adhesion of the cut edges, by means of presser fingers 22, 23 mounted on oppositely-rotating spindles 24, 25. The tapes then pass over rollers 43, 44, just clear of a roller 48, beneath a row of detector rollers 51, beneath a roller 52 to the take-up shaft 53 on which the reels 54 are wound. The shaft 53 is driven by a motor 55 and the cutter discs by a motor 67. The rollers 12, comb members 20, presser fingers 22, 23 and roller 48 are carried by a pivotally-mounted frame 42 which is, movable to and from the cutting position, shown in Figs. 2 and 3, by means of a pneumatic piston-and-cylinder unit 63 and toggle links 62. After the frame 42 has been moved to the cutting position, the rollers 12 are moved against the action of springs into contact with the cutter discs by means of pneumatic piston- and-cylinder units 88, Fig. 3. The comb members 20 and the presser fingers 22, 23 are moved into their operative positions by means of a pneumatic piston-and-cylinder unit 98, Fig. 3. In the event of cutting failure, the comb members 20 are displaced upwardly to open a switch M2, Fig. 3, and stop the feed motor 40, and the frame 42 is moved to the non-cutting position; simultaneously the unit 98 is operated to move the fingers 22, 23 to their non-operative positions and complete the lifting movement of the comb members 20. Similarly, breakage of any of the tapes 17 or non-threading of the web will allow the corresponding detector roller or rollers 51 to open a switch M1, Fig. 2, to perform the same sequence. A further switch M3, Fig. 3, is adapted to be closed on displacement of the mechanism operated by the unit 98 away from the cutting position. When the frame 42 is moved to the non-cutting position, the roller 48 swings downwardly to form a loop which absorbs any slackness in the web 11 or in the tapes 17 so that the frame can be swung back to the cutting position without substantially increasing the tension in the web or in the tapes. Simultaneously with the movement of the frame 42 to the non-cutting position, a shutter 72, Fig. 3, is moved downwardly to shield the web from the heated cutter discs. The switches M1, M2 and M3, the motors 40, 55 and 67 and the units 63, 88 and 98 are included in a control circuit, Fig. 5 (not shown).