| 摘要 |
An apparatus for heat-sealing the mouth of a bag supported on a conveyor includes a nozzle assembly for both spreading the mouth of the bag and evacuating the bag and a press assembly having confronting die units and resilient strip assemblies mounted to scissorable arms. The vacuum-sealing apparatus is positioned adjacent the side margin of the conveyor, and the bag having an article therein is horizontally supported on the conveyor with the mouth of the bag extending toward the heat-sealing apparatus over said side margin of the conveyor. The nozzle assembly includes a pair of parallel nozzle members of generally flat shape which are mounted to a drive mechanism such that the nozzle members may first be concurrently driven into the mouth of the bag and thereafter separated in a horizontal plane against the side margins of the bag mouth to an extent such that substantially all wrinkles are removed from the area of the bag to be sealed. While the nozzle members are separated to flatten the mouth of the bag, the press assembly arms are scissored together to compress the resilient strip assemblies against the flattened mouth portion of the bag and the enclosed nozzle members to form an air-tight seal thereat. The bag is then evacuated and/or gas-purged by means of passageways formed through the nozzle members. The nozzle members are thereafter removed while the resilient strips help maintain an air-tight seal and retain the mouth area to be sealed in a wrinkle-free condition. The bag is then sealed by the die units by forcing the press assembly arms further together.
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