Patent GB-736887-A (GB)
Title: Improvements in bag-making, filling and closing apparatus
IPC: B65B9/087
Filed: 1953-03-03
Abstract: 736,887. Making, filling and closing bags. PNEUMATIC SCALE CORPORATION, Ltd. March 3, 1953, No. 5945/53. Class 94 (1). [Also in Group XVIII] The machine comprises an endless gripper conveyer having spaced parallel runs and is arranged to make, fill and close two series of bags simultaneously. A folded or composite web of bag-forming material is positioned for engagement by the grippers at the commencement of each run of the conveyer and is advanced thereby to mechanisms which seal the web transversely between successive grippers, fill the opentopped bags thus formed with granular material, sever the bags in succession from the web and seal the mouths of the bags. In one form, Figs. 1 and 2, a continuously operated endless conveyer 10 carries a series of spaced pairs of spring-loaded grippers 22 which are extended downwardly beyond their pivots to straddle a fixed rail 34, the latter being widened at the beginning and end of each run to cause the grippers to open to receive the web or to release the completed bags. Webs of porous paper coated with a thermoplastic adhesive, are fed from rolls 24, 25 and are folded longitudinally by fixed members 44 before engagement by the grippers. A series of vertically-movable funnels 46 with depending nozzles 47 are carried by an endless chain 50, driven at the same speed as the conveyer 10, each funnel being mounted on a member 58 slidable in a guide 56 and carrying a roller 60 engaging a track 48. The latter is formed with high and low portions so that the nozzles are lowered between the folds of each web as the grippers close and are raised out of the bags after the filling operation. Each folded web, clamped around the nozzles by the grippers, then passes between a pair of heat-sealing rollers 84, 86 which are driven in synchronism. with the conveyer 10 and are formed with raised portions 85 which seal the folds together transversely between successive pairs of grippers, thus forming interconnected open-topped bags. Successive pairs of bags, one on each run of the conveyer, are then filled simultaneously with tea from a rotary hopper 90 having a series of apertures in its base for the reception of measuring chambers 106 which telescope into apertures in a ring 108 adjustable upwardly or downwardly to vary the quantity measured. The ring 108 is rotatable on a stationary disc 110 formed with apertures 114, 116 above the runs of the conveyer, the contents of two chambers being discharged simultaneously into two of the funnels as they pass over the apertures and under fixed scrapers 110. The hopper is replenished through a funnel 94 in a fixed cover 92. The filled bags are then severed from the webs by pairs of rotary cutters 122, 124, which cut through the centre lines of the transverse seals, and are carried by the grippers between pairs of heat-sealing rollers 150, 152 which seal their mouths. The grippers are then opened and the bags transferred to discharge conveyers 164, 166 by mechanisms 170 similar to that described in Specification 669,667. In a modification, Figs. 8 and 9 (not shown), two webs are supplied to each run of the conveyer and are sealed together along their bottom edges before passing into engagement with the grippers.