Opening arrangement for a container package
TECHNICAL FIELD 
     The present invention relates to an opening arrangement for container packages, comprising a sealing portion which inflexibly engages with and surrounds a pouring spout, whose end facing away from the container package consists of a continuous, liquid-tight material layer which is shaped in accordance with the inner configuration of the sealing portion. 
     BACKGROUND OF THE INVENTION 
     Container packages or cartons of the single-use disposable type are largely employed today to pack consumer goods such as, for example, beverages like milk or juice. The container package is usually made from packaging material in the form of a laminate with carrier layers of paperboard or cardboard, and different layers of thermoplastic laminated thereto. The laminate may also have a different core material, such as metal foil. The packaging material, which is often in the form of a web or sheet blank, is folded, sealed and finally formed into a liquid-tight container package. 
     The finished container package will preferably include an opening arrangement that is simple to open and pour from, which pours the liquid contents in a compact jet and without any risk of spilling or dripping. However, container packages manufactured from a packaging material consisting of a paper laminate may be difficult to tear open and fold to form a functional pouring spout. Moreover, when the intention is to reclose and reseal such container packages, it is not possible to make the package liquid-tight once again. 
     It is also known in the art to manufacture container packages having a main portion formed from a packaging laminate as described above but having an upper defining surface formed from an injection molded thermoplastic lid. The thermoplastic lid also includes an opening arrangement integral with the lid. This opening arrangement is relatively easy to open but is not liquid-tight on reclosure and resealing. 
     In order to obviate the above-outlined drawbacks, various forms of penetrating screw stoppers or plugs have been produced which are placed on the surface of the container package so that the screw plug penetrates through the surface layer when the package is opened. 
     It is further known in the art to form a partly integrated pouring spout from the surface of the packaging material. The pouring spout is surrounded by a sealing portion of the so-called screw stopper or plug type which, on being opened, tears off an outer portion of the pouring spout. That part of the pouring spout which is torn off during the opening operation has been sealed against the outer sealing portion by means of heat. As a result, the tear-off operation generally results in the pouring spout having a rough outer edge, which may render pouring of the contents enclosed in the container package difficult. 
     Not all of the prior art types of screw stopper opening are provided with an arrangement which prevents the unauthorized opening of the container package. Today, consumers greatly appreciate an opening arrangement in which it may immediately be seen that no unauthorized person has been able to open the container package and tamper with its contents. It is, therefore, desirably that a screw stopper or plug also include an arrangement which prevents the unauthorized opening of the container package. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     One object of the present invention is to provide an opening arrangement for container packages which, on opening, forms an aperture of the pouring spout with smooth edges. 
     A further object of the present invention is to device a screw stopper or plug which ensures that the consumer will be able to see that the container package has not been subjected to unauthorized opening. 
     These and other objects have been attained according to the present invention in that the opening arrangement of the type described by way of introduction includes a sealing portion having an inner, right-hand threaded part which is closed at the top, and an outer, left-hand threaded part in an upper region of which are provided at least two penetration devices oriented inwardly in the pouring spout. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A preferred embodiment of the present invention will now be described in greater detail hereinbelow with particular reference to the accompanying Drawings, in which: 
     FIG. 1 is a perspective view of an opening arrangement according to an embodiment of the present invention in a container package of known type; 
     FIG. 2 is a perspective view of the opening arrangement according to an embodiment of the present invention in another type of container package; 
     FIGS. 3A-3E are schematic, partially cross-sectional views depicting the application of an opening arrangement according to an embodiment of the present invention is applied to a container package such as is shown in FIG. 1; 
     FIG. 4 is a partially cross-sectional side view of an opening arrangement according to an embodiment of the present invention in an unopened state; and 
     FIG. 5 is a partially cross-sectional side view of an opening arrangement according to an embodiment of the present invention after opening has been instigated. 
     The Drawings show only those details essential to an understanding of the present invention. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENT 
     FIG. 1 shows an opening arrangement 1 according to the present invention applied to a container package 2 of known type. The container package 2, which is manufactured from a laminate with a core of paper, cardboard or metal to which is laminated different layers of thermoplastic, is folded, sealed and formed into a so-called gable-top carton 2. The opening arrangement 1 is placed on one of the upper defining surfaces 3 of the carton 2 forming a so-called gable-top. FIG. 1 shows only the outer sealing portion 4 of the opening arrangement 1, this portion being formed as a screw stopper of substantially conventional type, with interior threading, or alternatively a snap top with an inner bead (now shown). 
     FIG. 2 shows another type of container package 5 also of known type in which the lower portion of the container package 5 is manufactured from a laminate in accordance with the above description. The upper defining surface 6 of the container package 5 is formed from a thermoplastic panel, part of the surface of which has been formed into a pouring spout surrounded by an outer sealing portion 4. The remaining parts of the thermoplastic panel are folded about the upper edge of the container package 5 and are sealed by means of heat against the thermoplastic surface of the packaging laminate. 
     FIGS. 3A-3E schematically show how an opening arrangement 1 according to the present invention is applied to a container package 2 such as is shown in FIG. 1. As is seen in FIG. 3A, a circular opening 7 is formed in one of the upper sloping gable-top panels 3 of the container package 2. A thermoplastic panel 8 is placed inside the circular opening 7, this panel having a diameter which exceeds that of the circular opening 7 in the wall surface 3 of the container package 2. As shown in FIG. 3B, the thermoplastic panel 8 is sealed interiorly against the inner wall surface of the container package 2 by means of a sealing tool 9. 
     In FIG. 3C, the thermoplastic panel 8 is heated by a heated 10 to a temperature at which the thermoplastic plasticizes (for polyethylene approx. 110° C.) Once the thermoplastic panel 8 has become plasticized and pliable, it is subjected to vacuum or pressure forming in a molding tool 11 as illustrated in FIG. 3D. The outer sealing portion 4 is preferably used as the mold for vacuum forming the pouring spout 12 with threads 15. FIG. 3E finally shows the finished pouring spout 12 provided with threads 15. The pouring spout 1 is completely sealed and constitutes a liquid-tight part of the container package 2 when the outer sealing fin or flap 13 is finally sealed together after the filling operation. 
     FIG. 4 shows the opening arrangement 1 according to the present invention in that state in which it is to be found on the carton 2 when the consumer first handles it. As a result of the ring 16 which is fixed or sealed to the outer sealing portion 4, the consumer is guaranteed that no one can have tampered with or unrightfully opened the carton 2. The ring 16, which is made of plastic material, can be provided with a thumb grip 17 in order to facilitate grasping of the ring for tearing-off. Of course, the opening arrangement 1 may also be manufactured without the ring 16 but those advantages afforded by the ring 16 from the point of view of the consumer will then be lost. 
     The outer sealing portion 4 consists of two parts, the first being an outer screw stopper-like part 18 which is left-hand threaded. In the upper region of this outer screw stopper like part 18, there are provided at least two, and preferably four penetration devices 14. 
     The penetration devices 15 preferably are formed in the shape of small bevelled plastic pieces which project out from the inner wall of the outer part 18 of the sealing portion 4. The penetration devices 14 may also be formed of small metal pieces which have been fixed in place. 
     The sealing portion 4 also has an inner part 19 which is right-hand threaded an fits the threads 15 of the pouring spout 12. This inner part 19 is not of the same height as the outer part 18 but terminates before the penetration devices 14 with a tightly sealing plastic washer 20. The tightly sealing plastic washer 20 serves as a seal for the inner part 19 of the sealing portion 4 and the upper part of the pouring spout 12 is thus formed against this plastic washer 20. 
     FIG. 5 shows the opening arrangement 1 according to the present invention once the pull-ring 16 has been removed and the outer part 18 of the sealing portion 4 has been screwed with left-hand turn down to a stop heel 21. This stop heel 21 constitutes a component of the inner part 19 of the sealing portion 4 and is located most proximal the end wall of the container package. As the outer part 18 of the sealing portion 4 reaches this position, the penetration devices 14 cut through the plastic washer 20, which terminates the inner part 19 of the sealing portion 4, at the same time as they penetrate through the upper region of the pouring spout 12. The outer part 18 of the sealing portion 4 is locked in its lower position, for example by plastic barbs (not shown) which are placed between the outer part 18 and the stop heel 21. 
     Because the penetration devices 14 are placed in such a manner that they are angled slightly in towards the center of the pouring spout, they will, on removal of the outer sealing portion 4, retain the severed portions of the plastic washer 20 and the pouring spout 12. In order further to ensure retention of the severed portions of the plastic washer 20 and the pouring spout 12, a screw (not shown) may be fixed in the inside of the outer part 18 of the sealing portion 4 to penetrate down into the plastic washer 20 and the pouring spout 12 to facilitate retention of the severed portions when the sealing portion 4 is unscrewed from the opening arrangement 1. 
     The penetration devices 14 should be at least two in number but are four in number in the referred embodiment. The number of penetration devices 14 is dependant upon the length and pitch of the thread 15. The longer the thread 15, the fewer will be the number of penetration devices 14 required. The penetration devices 14 must together be capable of cutting off a complete circular surface of the plastic washer 20 and the pouring spout 12. 
     As will have been apparent from the above description, the present invention realizes an opening arrangement for conventional container packages or cartons which is simple to open and reseal. The consumer is guaranteed a container package which has not been opened by unauthorized hands and, as a result of the perforation or penetration devices characteristic of the present invention, the user will obtain a pouring spout which makes possible pouring of the contents of the container package without spilling and without dripping. 
     While this invention has been illustrated and described in accordance with a preferred embodiment, it is recognized that variations and changes may be made therein without departing from the invention as set forth in the claims.