Apparatus for packaging perishable articles

Claim 1

A WRAPPING MACHINE COMPRISING A TUBE FORMING DIE, SAID DIE HAVING A HORIZONTAL, LONGITUDINAL EXTENDING BASE WALL AND LATERALLY SPACED SIDE WALLS, EACH SIDE WALL HAVING ONE EDGE CONNECTED TO AND PROJECTING VERTICALLY FROM THE ASSOCIATED EDGE OF SAID HORIZONTAL BASE WALL, THE OTHER EDGES OF SID SIDE WALLS BEING FIRST INCLINED AWAY FROIM SAID BASE WALL AND THEN EXTENDING HORIZONTALLY AND VERTICALLY SPACED FROM SAID BASE WALL, HORIZONTAL FLANGES PROJECTING TOWARD EACH OTHER FROM THE HORIZONTAL PORTIONS OF SAID OTHER EDGES OF THE SIDE WALLS, THE OPPOSED FREE EDGES OF SAID HORIZONTAL FLANGES FIRST CONVERGING TOWARD ONE ANOTHER TO FORM A V-SHAPED CHANNEL, AND THEN CONTINUING IN A GENERALLY PARALLEL SPACED RELATION TO FORM A LONGITUDINAL SLOT, MEANS AT EACH OF SAID HORIZONTAL FLANGES ADJACENT THE APEX OF SAID V-SHAPED CHANNEL FOR CAMMING THE LATERAL EDGE REGIONS OF SAID WEB, MEANS UPSTREAM OF SAID CAMMING MEANS FOR PRESSING THE LATERAL EDGES REGIONS OF THE WEB AGAINST THE OUTER FACES OF SAID HORIZONTAL DIE FLANGES, A THIN HORIZONTALLY EXTENDING AND VERTICALLY DISPOSED GAS INJECTION NOZZLE LONGITUDINALLY ALIGNED WITH SAID SLOT IN THE TUBE FORMING DIE, THE GAS EMITTING EDGE OF SAID NOZZLE LYING SUBSTANTIALLY IN THE PLANE OF THE HORIZONTAL FLANGES OF SAID TUBE FORMING DIE, MEANS FOR ADVANCING A WEB OF WRAPPING MATERIAL AND THE ARTICLES TO BE WRAPPED THROUGH SAID TUBE FORMING DIE WITH SAID DIE CAUSING SAID WEB TO CONFORM TO AN ARTICLE WITHIN THE DIE TO FORM A TUBE, WITH THE LATERAL EDGE PORTIONS OF THE WEB OVERLYING SAID HORIZONTAL FLANGES OF THE DIE, SAID PRESSING MEANS LOCALLY HOLDING THE LATERAL EDGE REGIONS OF THE WEB AGAINST THE OUTER FACES OF THE HORIZONTAL FLANGES OF THE DIE, SAID CAMMING MEANS THEREAFTER CAMMING THE LATERAL EDGE REGIONS OF THE WEB INTO VERTICAL, LATERALLY SPACED WEB FLANGES FOR STRADDLING SAID NOZZLE AS THE BUE ADVANCES, AND MEANS DOWNSTREAM OF SAID NOZZLE FOR SEALING SAID WEB FLANGES TOGETHER.