GB442617A - Improvements in or relating to bags and methods of and machines for making the same - Google Patents

Abstract

442,617. Cutting paper &c. STEVENS, A. H., 5, Quality Court, Chancery Lane, London.-(Shellmar Products Co.; 3501, West 48th Place, Chicago, U.S.A.) Nov. 29, 1934, No. 34358. [Class 31 (i)] [See also Group XVII] A paper &c. bagmaking machine includes a tube-forming mechanism, a smooth cutting shoe 74 reciprocable in the tube formed thereby and cutting rolls 78, 79 mounted above and below the shoe and spaced therefrom carrying smooth knives 82 adapted to roll against the sides of the shoe to pinch-cut or scorecut the tube of paper &c. in the production of an elementary bag tube. A web 10 of cellulosic film material &c. from a roll 11, is led beneath a spring biassed roll 26 to prevent breakage of web in starting up, and thence over a roll 24 where a longitudinal edge is gummed by a wheel 23 pivoted on a shaft 20 and fed from a bath 21 ; the wheel 23 being driven by a friction wheel 25 from the travelling web and bearing by gravity against the web. The frame 19 which carries the gumming device and roll 26 is adjustable through rack-andpinion mechanism 30. The web is now formed into a tube, which may be gussetted, over former plates 42, 43 separated by longitudinal plates 44, the adjustable side plates 49 forming the side gussets. A finger 51 separates the edges of the tube and prevents the gum from being smeared, while friction rolls 50 maintain the material tightly about the former. Between the plates 44 and carried by ball bearings 76, is a travelling mandrel 73 formed with a hardened smooth cutting shoe 74 and reciprocated horizontally by adjustable throw mechanism 89, 90, 91, 92 driven from the cutter rolls 78, 79 and thence through a resilient connection 95, 96 and an arm 37. The adjustable draw rolls 53 are carried in spring-pressed bearings, the upper rolls being rubber-faced and driving against bottom rolls of steel. On the lower feed roll shaft a central roll is fitted to support the reciprocating mandrel 73, which may move at the rate of 250 cycles per minute. The cutter rolls 78, 79 of circumference equal to the length of a bag blank. carry knives 82 of any desired shape held therein by wedge blocks 80, 81. The knives are arranged to extend beyond the outer surface of the rolls and then rubber sheets 83 are adhesively secured about the knives. The purpose of the sheets is to ensure that when the cutting shoe 74 comes between the cutter rolls the rubber sheets 83 will grip the same and, by reason of the resilient driving connection 95, 96, obtain uniform speed of knives and cutting shoe whilst cutting is in progress. The cutters 82 pinch-cut or scorecut the tube on each side of the cutting shoe leaving the extreme edges uncut. Rolls 97, 98 moving at the same speed as the web now firmly grip the partly severed tubular blank which is torn away by fast moving rolls 102, 103 rubber covered at 105 and carried in spring pressed bearings. The separated tubular blank is then passed to bottom forming apparatus 118, 119, a plate 108 effecting the guiding of the blank thereto. Rubber-faced rolls 136 then forward the completed bags to a suitable hopper.