GB844014A - Packaging machine - Google Patents

Abstract

844,014. Packaging-machines. ROTO WRAP MACHINE CORPORATION. Aug. 19, 1958 [Aug. 20, 1957], No. 26634/58. Class 94(1). A machine for packaging articles such as slabs of cheese between webs of film and in the presence of inert gas comprises a chamber in which articles are scrubbed by the gas to remove air, the articles being enclosed between upper and lower webs which are sealed about them to form the packages. The articles 14 are fed by a belt 16 on to a conveyer 18 comprising spaced strands 20 to give a minimum of contact with the articles. The conveyer 18 carries them beneath a flexible roller 22, which makes a gas tight seal with the strands and one of the supporting grooved rollers 24, into a chamber 32. Inert gas is sprayed on to the articles from above and below the conveyer strands by perforated pipes 34, the pressure in the chamber 32 being above atmospheric, and the articles pass beneath a further flexible roller 22 into a chamber 36. Gas is supplied to the chamber 36 by pipes 38, Fig. 2 (not shown), and maintains it at a higher pressure than that in the chamber 32. Webs 42 44 are led through slits into a former 40 and the articles are fed between them for exit from the former enclosed in a finned tube. The side edges or fins are heat sealed by opposed pairs of rollers 68 and pressure is applied to the seals by further rollers 70. The tube is sealed transversely between the articles by members 72 having a combined reciprocating and rotary motion, and passes between gas expelling soft rollers 74. Cutters flanked by pressure pads 78 and movable with the tube during cutting, sever the individual packages.