Package making – Apparatus for forming or partially forming receptacle and... – Forming a pocket – depression – or hollow compartment by...
Reexamination Certificate
1999-08-19
2001-12-04
Vo, Peter (Department: 3721)
Package making
Apparatus for forming or partially forming receptacle and...
Forming a pocket, depression, or hollow compartment by...
C053S561000, C425S526000, C425S529000, C425S541000
Reexamination Certificate
active
06324819
ABSTRACT:
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable
REFERENCE TO MICROFICHE APPENDIX
Not applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method of producing packaging containers of plastics, to a packaging container, in particular produced according to said method, a molding station for a plastic packaging container and a packaging machine comprising such a molding station and to a method of producing filled and closed containers.
2. Description of Related Prior Art
So far the production of packaging containers of plastics, in particular for packing foodstuff, has had various disadvantages which have had the effect that efficiently produced plastic packaging containers only exist in a very limited number of shapes and are normally devoid of any reclosing possibilities.
In particular, it has so far only been possible to produce straight-walled, cylindrical or conical cups or containers without any undercuts by deep-drawing, blow-molding or similar processes.
Such containers, however, turn out to be troublesome as to their stability and standing capacity. Moreover, liquid substances, for instance paste-like foodstuff, cannot be filled into such containers at a high speed because the reaction forces always-tend to splash back the packing material during the filling process. Therefore, liquid substances cannot be filled into straight-walled or conical containers at such a high speed as is desired and, in particular, is also possible with containers having undercuts, in which the filling opening has a smaller cross-section than the remaining container cross-section, whereby back splashing or ejection is avoided.
For manufacturing reasons packaging containers which have been made from a plastic film could thus not be provided with shapes that have turned out to be advantageous in the glass or ceramic sector or in the case of injection-molded containers. Moreover, with packaging containers made from a plastic film, it is often not possible to permanently reclose the corresponding filling openings because they are often only closed by a disposable sealing film which after having been torn off cannot be permanently closed again.
SUMMARY OF THE INVENTION
It is therefore the object of the present invention to provide a method of producing packaging containers of plastics, a molding station for such a plastic packaging container, a packaging machine, a plastic packaging container and a method of producing filled and closed packaging containers which exhibit a much greater variety as to the producibility of packaging containers, in particular packaging for foodstuff, and which make it possible to combine the advantages of conventional packaging containers which are not produced on the basis of a plastic film, that is e.g. reclosability, high standing capacity and dimensional stability, together with a highly efficient production.
In a method of the aforementioned type this object is achieved according to the invention in that the film is first displaced by at least one plug of the upper mold in a deep-drawing process into a mold cavity of the lower mold and a final molding operation is subsequently performed by a blow-molding process with supply of a gaseous medium into the mold, with the film being placed on a wall of the mold cavity formed in the lower mold. Packaging containers having virtually any desired cross-section of a high standing capacity can thus be produced which exhibit excellent packaging characteristics even at a reduced wall thickness and can e.g. be provided with screw caps.
Preferably, the film is preheated prior to the impact of the plug of the upper mold, and the deep-drawing process is carried out at a variable speed of the plug over the plug path.
Depending on a predetermined plug position, in particular close to the end or after the end of the deep-drawing process (maximum plug path of the plug of the upper mold), the blow-molding operation is started by blowing compressed air into the annular space between the plug and the film-material molding which has been preformed in the mold cavity of the lower mold; this has the effect that the film is completely placed on the mold cavity in the lower mold, also in a preferably upper undercut area.
As for the molding station for molding a plastic packaging container, the aforementioned object is achieved according to the invention in that the molding station comprises at least one upper mold and at least one lower mold, with an axially displaceable plug being provided in the tipper mold and a mold cavity in the lower mold, the plug being displaceable under (Jeep-drawing of a plastic film into the mold cavity and the lower mold being laterally divided such that the lower mold halves are movable substantially in a direction perpendicular to a motional direction of the plug for opening and closing the lower mold, and a compressed-gas supply means being provided for finally shaping the packaging container in the mold cavity through a blow molding process, in particular by the action of compressed air.
The bottom portion of the mold cavity in the lower mold is preferably formed by a counter-plug which is optionally also movable in a vertical direction.
Preferably, the mold members of the lower mold that form the mold cavity are at least partly subjected to a local temperature control by an at least partial cooling or heating operation.
The aforementioned object is achieved according to the invention with respect to the packaging machine in that said machine comprises a molding station for plastic packaging containers, in which station a packaging container having at least one undercut can be produced from a plastic film in a combined deep-drawing/blow-molding process, a filling station for filling the packaging container with a packing material, a sealing station for sealing a filling opening of the packaging container, a separating station for individualizing the packaging containers and a discharge station for the filled and sealed packaging containers.
It is advantageously possible through the solution according to the invention to produce e.g. packed foodstuff in a compact packaging machine unit, wherein at the input side the plastic film is continuously supplied as a semifinished product for forming the packaging container in the molding station while at the output side the packing material which has individually been packed into the individual packaging containers leaves the packaging machine.
As for the plastic packaging container itself, the aforementioned object is achieved according to the invention in that the packaging container which has been produced from a plastic film has at least one undercut and is closable with a sealing film provided with an opening device and/or is provided with closing means for holding a cover.
Preferably, the packaging container comprises a radially projecting circumferential edge portion for holding an associated cover of a plastic film.
It is advantageous for a permanent reclosing of the once-opened packaging container that said container comprises a screw thread as a closing means in a neck or bottom portion of the packaging container for screwing a cover, which also consists, in particular, of a plastic material.
REFERENCES:
patent: 2940120 (1960-06-01), Grebowiec
patent: 3808772 (1974-05-01), Turtschan
patent: 3837782 (1974-09-01), Meissner et al.
patent: 4543770 (1985-10-01), Walter et al.
patent: 4565052 (1986-01-01), Hautemont
patent: 4732557 (1988-03-01), Aoki
patent: 4859170 (1989-08-01), Aoki
patent: 5178817 (1993-01-01), Yamada et al.
patent: 5306325 (1994-04-01), Smith et al.
patent: 5941054 (1999-08-01), Valyi
patent: 5975880 (1999-11-01), Takada et al.
patent: 6045746 (2000-04-01), Komine et al.
patent: 2.261.812 (1973-06-01), None
patent: 106.425 (1984-04-01), None
patent: 564 382 (1993-06-01), None
patent: 1.262.380 (1961-04-01), None
patent: 1.427.784 (1966-01-01), None
patent: 1.554.475 (1968-09-01), None
patent: 2.477.948 (1981-09-01), None
patent: WO85/03488 (1985-08-01), None
Huynh Louis K.
Kourtoglou S.A. Food Packaging Machinery
Laubscher & Laubscher
Vo Peter
LandOfFree
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