Patent ID: 7021032

Claim:
In a tube-filling machine, a method for end sealing of tubes of the kind which has an inner tube surrounded by a gap and an outer tube, both connected to a common tube shoulder which has means for delivering product from the inner tube and the outer tube through an emptying opening, said method comprising feeding said filled tubes individually or alternatively in groups, to an end sealing station working with clamping jaws located along a conveyor path, by a conveyor working stepwise, in the requisite order for processing, the tubes being end sealed in the end sealing station, and the tubes being delivered from the tube-filling machine in a feed-out station, activating the heat-sealable end of a tube for the purpose of sealing the end of a tube filled with product in the following end sealing station working with clamping jaws by introducing an outer annular part ( 24 ) provided with outlet openings of a two-part hot air nozzle into the gap between the inner tube and the outer tube, and introducing an essentially cylindrical part with outlet openings of said nozzle into the inner tube, arranging a cooled, centering sleeve around the outer side of the annular part leaving a gap, introducing the outer tube into said gap between the sleeve and annular part, and supplying hot gas through separate passages from said cylindrical part and outer annular part to the inner side of the inner tube end and the inner side of the outer tube end in order to optimize the heat supply of different kinds of material in the inner and outer tubes.