MANUFACTURING SACKS OR BAGS

摘要

1,253,292. Making bags. WINDMOLLER & HOLSCHER. 13 Jan., 1969 [13 Jan., 1968], No. 1814/69. Heading B5D. Bags having a liner which protrudes from a wrapper are made in an automatic and continuous operation. A web A of a single ply or a plurality of transversely staggered plies of paper is fed by rolls 1 to a perforator 2 producing transverse lines of perforations dividing the web into wrapper lengths, and is then fed to a glue applicator 4 applying glue dots 5, 51 to the web. A web or tube E is cut into lengths ES corresponding to the liner by a guillotine 9, the lengths are then fed by an apparatus 10, which overlaps the pieces ES by an amount X corresponding to the distance they are to protrude from the wrapper, to a conveyer 11 which feeds them to the wrapper web A and the leading end of a liner length is adhered to the web A by the glue dots 5. The web A is formed into a tube by a tube-laying device 6, and if the liner lengths are in the form of sheets they are also formed in the tubes by the device 6, and the web is then torn along the perforation by a device 7. The leading edge of the liner is adhesively tacked to the wrapper tube and moves therewith, the trailing end slipping from the end of the succeeding liner which it overlaps, so that it protrudes from the wrapper tube to the extent of the former overlap. If the liner is supplied in tubular form its bottom end may be sealed by a heat seal 13 prior to being cut by the guillotine, alternatively the wrapper and liner may be closed at their leading ends by a stitched seam or by a folded end closure. The overlapping apparatus may be such as is used for shingling bags delivered from a bagmaking machine, but as shown, comprises conveyer belts 14, 17 which are driven faster than the succeeding conveyer 11. Belt pulleys 15, 18 at the receiving end are fixed, but pulleys 16, 19 at the delivery end are longitudinally reciprocatable. When the leading end of a liner length is delivered to the conveyer 11 the pulleys 16, 19 are moved fully rightwardly close to the conveyer 11, the pulleys are then moved leftwardly to afford space for the formation of a loop in the liner length caused by the different speeds of the conveyers. The trailing end of the length is released from between the belts 14, 17 when the pulleys 16, 19 are in their fully lefthand position, and they are then shifted rightwardly to feed the leading end of the next length to the conveyer 11 so as to overlap the trailing end of the preceding length by the desired amount. The conveyer 11 is driven by bevel gearing 34, 35 at the same speed as the feed rolls 1; the conveyer belts 14, 17 and feed rolls 8 for the liner are driven from the main machine drive by way of an infinitely variable gear 40 permitting the overlap to be adjusted as desired.