Improvements in packaging machines

摘要

1,065,144. Packaging machines. SPERRY RAND CORPORATION. May 21, 1964 [May 21, 1963], No. 21002/64. Heading B8C. A machine for making bags from a continuous web formed into a tube on a former 4, and sealed transversely by jaws 38, 32, weighed quantities of material 132 being cyclically supplied to the tube, has means 94, 88 for stripping the fragments of material from the region to be sealed, deflating means 124 for squeezing out air which tends to be trapped in the bags, and closure blades 116 for supporting the next charge of material while the jaws operate. The tube is formed from a web 6 pulled downwardly through the former 4 by vertically reciprocating jaws 38, 32 carried by beams 20 and edge-sealed by means 8. Attached to each beam 20 is a stripper member 94, 88 and these members close together around the tube, before the sealing jaws close. Material from the charge 134 in the region to be sealed is thus forced downwardly during the initial downward movement of the beams 20. The next charge 132 is prevented from falling in the tube by the pivoted closure blades 116. At the same time rods 122 pivoted to beams 20 at pivots 123, and having curved plates 124, are released from fixed stops 130 and swing inwards and downwards under gravity and press the sides of the bag together, expelling excess air upwardly between small vents between the stripper plates 94, 88 and the closure blades 116. Pressure fluid is then admitted to cylinders (34, Fig. 3) to project sealing jaws 38 towards fixed jaws 32 to heat-seal the tube transversely. The closed blades 116 are then opened allowing the material 132 to fall. The jaws then pull down more bag material for the next cycle and the previously formed bag 134 is severed. With the jaws and strippers separated they are moved to their initial uppermost position to commence the next cycle. The sealing jaws and associated members are cyclically raised by a chain (48, Fig. 1) passing over a sprocket wheel (42, Fig. 1) and operated by a crank arm (52, Fig. 1) and are sufficiently heavy to pull the web down under gravity. The sealing jaws are moved horizontally by links (30, Fig. 4) pivoted to a disc (28, Fig. 4) oscillated by a vertical square shaft (22, Fig. 4) driven by a chain (70, Fig. 1) and lever (76, Fig. 1) geared to the crank arm (52, Fig. 1). The mechanism is duplicated so that two bags are made, filled and sealed simultaneously.