GB377972A - Improvements in or relating to methods and machines for the manufacture of bags having crossed ends - Google Patents

Abstract

377,972. Making paper bags. ANDREAS, A., 3, Engelstrasse, Munster, Westphalia, Germany. April 30, 1931, No. 12798. Convention date, April 30, 1930. Addition to 361,318. [Class 94 (ii).] A paper tube, which may comprise more than one layer of paper and display printed matter, is cut into sections whereof the ends of one wall of the section are folded over automatically preparatory to cross bottoms being formed as described in the parent Specification, the finished bags being then counted and bundled. Four layers of paper 2, gummed at 9 and the uppermost printed at 8, are brought together and secured by rolls 3, staples having been provided from a supply 10 to strengthen the web thus formed. While a former 4 converts the web into a tube, a rotary cutter 12 makes semicircular incisions in the upper wall of the tube and thereafter a rotary knife cuts it into bag sections which are deposited on a conveyer 7 moving transversely of the direction of movement of the web. A narrow belt 13, above the conveyer 7 guides each section between the halves 19, 19<1> of a prism which rotates about its longitudinal axis on a shaft 14 supported in bearings 15, 16. Associated with each half prism is a stationary drum 29 formed with cam-tracks 28 adapted to operate sets of levers 22, 23, 25 of which each side of the prism carries one set. A further camtrack 33 actuates a slide 30 movable parallel to the shaft 14. The tube section is seized at each end by a clamp 21 on one of the levers 22 and pressed into a stepped position 19a of the prism, the ends being thus bent upwards. Fingers 26 on the lever 25 pass through the semicircular cuts in the upper wall and press down the lower wall. The ends of the bag are thus opened and. the slides 30 pass into them to fold the upper wall over about the clamps 21. Plates 24 on the lever 22 then press the triangular end flaps formed by the folding operation. The prism moves in the opposite sense to the conveyer 7 and stops 40 remove the tube section on to another conveyer for transference to the bottom-forming machine described in the parent Specification. The finished bags drop on to an intermittently moving conveyer disposed transversely of the bottom-folding machine and are thereby counted and bundled. The prism-half 91<1> is slidably keyed to the shaft 14 to make it adjustable for different bag lengths, its drum 29 being likewise displaceable along the machine bed. The device may supply two bottom-folding mechanisms, feeding to them alternately, the bags, when finished, being collected on a single conveyer. Moreover, a single tube forming mechanism may supply two endfolding machines.