Patent ID: 6959739

Claim:
A method for filling tubes having a first end having a delivery opening and a second end and including an inner tube, an outer tube separated from said inner tube by a predetermined gap, and a common tube shoulder at said first end of said tube connecting said inner tube to said outer tube for delivering product from said inner and outer tubes to said delivery opening, said method comprising delivering said tube to a tube filling station along a conveyor path, filling said predetermined gap at said tube filling station by means of an elongated nozzle including a plurality of filling pipes corresponding to said predetermined gap and a mandrel for insertion into said inner tube, said filling step comprising centering said outer tube with respect to said elongated nozzle by means of a centering sleeve disposed externally around said elongated nozzle to provide said outer tube with its nominal cross-sectional shape and centering said inner tube with respect to said elongated nozzle by means of said mandrel disposed within said inner tube to provide said inner tube with its nominal cross-sectional shape, positioning said elongated nozzle proximate to said common tube shoulder, filling said predetermined gap with said plurality of filling tubes while guiding said elongated nozzle out of said second end of said tube while retaining said centering sleeve around said elongated nozzle, and filling said inner tube.