Packaging and filling machine

A packaging and filling machine, in which a web-like packaging laminated material is spliced in a splice of next web-like packaging laminated material, the web-like packaging material is fed continually and is formed to a tube shape, the tube overlapped in both ends of the packaging material is longitudinally sealed along the longitudinal direction, liquid food is filled up to a liquid level of a predetermined position above an outlet of a filling pipe from the filling pipe in the tube-like packaging material conveyed continually and vertically downward, while the tube is held with seal jaws and counter jaws along transversal direction below the liquid level, and is pulled down, the tube is transversally sealed, while the tube is held with the seal jaws and the counter jaws along transversal direction below the liquid level, the tube is held with forming flaps at the same time to be preformed, the tube is cut in the transversal seal zone, and packaged containers are manufactured, the packaging and filling machine comprising:

• a pressure flange and a positive pressure keeping means,
• the pressure flange being arranged around the periphery of the filling pipe below the liquid level in the tube-like packaging material,
• the pressure flange controlling free flows from the lower part to the upper part of the liquid food filled in the tube to keep the pressure of the liquid food in the tube below the pressure flange a positive pressure, and to make the preforming with forming flaps easy,
• the positive pressure keeping means absorbing fluctuation of the pressure of the liquid food in the tube below the pressure flange, and preventing the liquid food pressure from dropping in negative pressure to keep the pressure of the liquid food in the tube below the pressure flange a positive pressure,
• wherein a flow control means of the positive pressure keeping means is equipped in the pressure flange, the flow control means controls the flow of liquid food from the lower portion to the upper portion by the pressure flange, opens up the flow of the liquid food from the upper portion to the lower portion about the pressure flange, and absorbs decrease of the liquid food pressure to negative pressure to prevent outside atmosphere substance from making an invasion into the tube, and
• wherein the flow control means of the positive pressure keeping means is a ring-like floating valve arranged below the pressure flange around the periphery of the filling pipe with freely up-and-down mobility according to the flow of the liquid food, the pressure flange has a passing hole penetrating through the flange up and down, and the ring-like floating valve opens or blocks the passing hole according to the flow of the liquid food, partially or totally.