Sealing machine for closure of evacuated packaging bags has a pressurized elastic hose which extends beyond the sealing tool face to maintain vacuum in the package as a closure seal is made

摘要

Two sealing tools(1,2) are employed, one of which has a sealing zone with an elastic cover(3), which when under pressure forms a hose. The hose is located on a rebated surface(F') of the tool and when under pressure has a cross-section which projects above the surface(F) of the sealing zone by at least the height of a suction tube(AR) which is inserted into the bag for evacuation. A part(5) of the sealing tool which carries the hose(3) is insulated from the adjacent heated tool part(4) by a gap or heat insulation(6). In the pressureless state the hose has a circular cross-section, with a flattened wall part(3) which is attached to the rebated surface(F') of the unheated tool part(5). The hose fills the step between the two half parts of the tool(1) and is connected to compressed air. When the hose is located on only one sealing tool(1or2) the inserted end of the suction tube(AR) has a flat trapezium cross-section whose narrow side contacts the pressurized hose and when located on both tools has an oval or elongated hole cross-section.