Tube feeding mechanism for packaging machine

Claim 1

A PACKAGING MACHINE HAVING A TUBE FORMING MANDREL, A FORMING DEVICE AT ONE END OF THE MANDREL FOR PROGRESSIVELY GUIDING A WEB OF PLIABLE HEAT SEALABLE FILM MATERIAL INTO TUBE FORMATION AROUND THE MANDREL WITH MARGINAL PORTIONS THEREOF IN SUPERIMPOSED SEAM FORMING RELATION, A HEAT SEALING MECHANISM ADJACENT THE MANDREL FOR SEALING SAID MARGINAL WEB PORTIONS AND FORMING THEREIN A CONTINUOUS SEAM, MEANS FOR FEEDING A PRODUCT THROUGH THE HOLLOW MANDREL AND INTO THE TUBE FORMED THEREON, AND MECHANISM FOR CONTINOUSLY ADVANCING SAID TUBE IN THE AXIAL DIRECTION OF THE MANDREL, SAID TUBE ADVANCING MECHANISM COMPRISING PAIRS OF RELATIVELY NARROW DRIVE WHEELS DISPOSED IN LATERALLY SPACED RELATION ON OPPOSITE SIDES OF THE DISCHARGE END OF THE HOLLOW MANDREL FOR ENGAGING IN TUBE ADVANCING RELATION BETWEEN THE WHEELS OF EACH PAIR THEREOF FOLDED SIDE EDGE PORTIONS ON OPPOSITE SIDES OF THE FORMED TUBE, MEANS FOR DRIVING THE FEED WHEELS, DEPENDING SUPPORT MEMBERS MOUNTED FOR PIVOTAL MOVEMENT ON THE AXIS OF ROTATION OF THE FEED WHEELS, TUBE ENGAGING, PRESSURE APPLYING ROLLERS MOUNTED ON SAID DEPENDING MEMBERS, MEANS FOR DRIVING SAID PRESSURE APPLYING ROLLERS IN THE SAME DIRECTION AS THE ADVANCE OF THE FILLED TUBE, AND RESILIENT MEANS FOR HOLDING THE SUPPORTING MEMBERS IN SPACED RELATION SO AS TO CAUSE THE APPLYING ROLLERS TO CONTINUOUSLY ENGAGE THE FILLED TUBE AND APPLY UNIFORM PRESSURE TO SAID FILLED TUBE.