Pack for liquids having edge protection, process for the production thereof and apparatus for carrying out the process

A process for the production of a pack for liquids, the pack comprising a plastics strip and walls formed from a carrier material coated on at least one side with plastics material,

• the pack having side walls of a tubular configuration, a longitudinal sealing seam, and a bottom having a transverse sealing seam,
• the longitudinal sealing seam of the pack including over-lapping interior and exterior edge portions of the side walls, the interior edge portion having a cut edge and interior and exterior surfaces, the plastics strip being laid in a cross-sectional U-shape around the interior edge portion, and the plastics strip being sealed onto both interior and exterior surfaces of said interior edge,
• wherein the process comprises sealing the plastics strip in a longitudinal direction onto one surface of the edge portion of a forwardly moving web of carrier material, the web being in a flat condition, the plastics strip partially overlapping one surface of the interior edge portion of the web,
• laying the portion of the plastics strip projecting beyond the cut edge over in a U-shaped cross-section configuration,
• and sealing the portion of the plastics so laid over onto the opposite surface of the interior edge portion.

Apparatus for manufacturing a pack for liquids, wherein the pack comprises a plastics strip and walls of a carrier material coated on at least one side with plastics material, the pack having side walls of a tubular configuration, a longitudinal sealing seam, and a bottom having a transverse sealing seam, the longitudinal sealing seam of the pack including overlapping interior and exterior edge portions of the side walls, the interior edge portion having a cut edge and interior and exterior surfaces, the plastics strip being laid in a cross-sectional U-shape around the interior edge portion, and the plastics strip being sealed onto both the interior and exterior surfaces of the interior edge portion;

• the apparatus comprising:
• sealing and cooperating jaws for partially sealing the plastics strip onto one surface of the interior edge portion,
• an elongated slide shoe and sealing means for attaching the plastics strip to the opposite surface of the interior edge portion, the slide shoe and sealing means being laterally disposed in the direction of conveying movement of the web and beside the path of conveying movement thereof, and
• folding and sealing means for the longitudinal sealing seam further laterally disposed in the direction of conveying movement of the web.