| 摘要 |
631,807. Making paper bags. CELLOPHANE SOC. ANON. Oct. 25, 1946, No. 31739. Convention date, Oct. 21, 1944. [Class 94(ii)] A block bottom bag, Fig. 1, of the kind having end folds 1 whose height determines the level to which the bag is filled, and end flaps 2 and 3 whose overlapping edges are stuck together, is made by means of a machine, Fig. 6, of the kind in which a plunger 7 forces a sheet of material through an aperture in a table 4 and into a box 9 provided with members 10, 11 and 12 which produce and fold over on each other the flaps 2 and 3. The machine is characterised in that a suction chamber 30 is provided at the delivery end of the folding box, the chamber being adapted to retain the completed bag (shown dotted) by suction when plunger and chamber are moved apart. The plunger is provided with a handle 8 and is connected to slides 16 mounted on guide rods 18 and 19. Heated rolls 13 are provided for sealing together the end flaps when the bag is made from thermoplastic material, the rotation of the rolls being controlled by the movement of the plunger. Flaps 34, pivoted to the chamber, are stated in the Specification to be adapted to flatten the bag after manufacture. In a modification a pair of folding boxes are disposed end to end and sheets are continuously fed between the boxes, a single plunger being provided to form a bag alternately in each box. The two suction chambers, which are reciprocated alternately to remove a bag from each end of the plunger, are alternately coupled electro-magnetically to the plunger, the latter being forced through a folding box alternately in opposite directions with reciprocation of the suction chambers. In a further modification the movement of the aforesaid single plunger is effected mechanically. |
