Abstract:
A closure divice for a container including a pourer designed to be fixed on a neck of the container wherein the closure device includes a cover assembly adapted to be mounted on the neck and over the pourer. The cover assembly includes a cap movable between a first position wherein it closes the neck and the pourer from the outside and a second position where it allows access to the neck and to the pourer. The pourer is arranged at least partly inside the neck. The cap is provided with a skirt extending, in the first position of the cap, inside the neck. The skirt has at least one flange capable, when the cap is in the first position, of exerting a force urging the pourer against an edge of the neck.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The invention relates to a device for closing a container and to a container equipped with such a device. 
   2. Brief Description of the Related Art 
   It is known to make containers for liquid, such as milk bottles made of plastics material, for example high density polyethylene. It is essential that such containers be hermetically closed particularly with a view to their transport from the point of sale to the place of use. To that end, it may be provided to seal the neck of a bottle with a membrane based on aluminum. However, in practice, it proves delicate to remove such a membrane and it is not rare for pieces of this membrane to remain in place on the neck, this rendering use of the container delicate and raising problems during its reprocessing for valorisation, as the residues of aluminum must be treated differently from the body of plastics material. In addition, the known containers tend to leak after the aluminum-based membrane has been removed, i.e. after first use of the fluid that they contain. 
   Attempts have been made to produce systems for closing bottles without a membrane, particularly by means of screwed stoppers. However, as bottles are most often made by blowing a parison and/or extrusion, relatively great manufacturing tolerances appear at their neck while irregularities cannot always be eliminated at the plan of the juncture in the mold. Such variations in dimensions induce risks of leakage which are not acceptable in practice. 
   The problems set forth hereinabove are also raised for bottles equipped with a pourer intended to promote flow of a liquid. 
   Furthermore, it is known from DE-A-1 532 390 to provide a cylindrical skirt on the inner surface of the bottom of a stopper, this skirt being supposed to undergo a centripetal force exerted by a pourer. The tightness obtained with this device cannot be guaranteed, particularly due to the fact that the skirt of the stopper is not rigid but, on the contrary, provided to be deformed. 
   SUMMARY OF THE INVENTION 
   It is a particular object of the invention to overcome these drawbacks by proposing a closure device not presenting an aluminum membrane and allowing a container to be hermetically closed before and after the first use of the fluid that it contains. 
   In this spirit, the invention relates to a container provided with a neck and equipped with a closure device comprising a pourer designed to be permanently fixed on this neck, and a cap adapted to be mounted on this neck and/or this pourer, being mobile between a first position wherein it isolates the neck and the pourer from the outside and a second position where it allows access to this neck and to this pourer, the pourer being arranged at least partly inside the neck. The cap is provided with a skirt extending, in the afore-mentioned first position and from an inner surface of the cap, up to inside the neck. This device is characterized in that this skirt bears at least an outer flange arranged so that it exerts, in the afore-mentioned first position and against an inner radial surface of the pourer, a force which is centrifugal with respect to an axis of symmetry and urging this pourer against an inside end edge of the neck. 
   The skirt of the invention compresses the pourer against the neck of the container, which makes it possible to ensure tightness, on the one hand, between the pourer and the neck and, on the other hand, between the skirt and the pourer. The tightness between the pourer and the neck is necessary for the whole life of the container while the tightness between the cap and the pourer is useful as soon as a membrane possibly obturating the pourer has been removed, i.e. after first use of the fluid contained in the container. The concentration of force obtained thanks to the flange allows a localised and firm abutment of the pourer against the inner edge of the neck. 
   According to advantageous but non-obligatory aspects of the invention, the device incorporates one or more of the following characteristics:
         The afore-mentioned edge and skirt are substantially cylindrical, while the force exerted by the skirt on the pourer is centrifugal with respect to an axis of symmetry of the afore-mentioned edge.   In the first position, the flange is arranged opposite the edge of the neck, the force exerted by the flange tending to compress a part of the pourer against this edge. Such compression of the pourer takes advantage of its deformable nature and ensures the desired tightness.   The skirt is equipped with two outer flanges bearing against the inner radial surface of the pourer, the second flange being provided to ensure clipping between the cap and the pourer after the first use of the container. The nominal outer diameter of the flange or flanges may also be provided to be greater than or equal to the diameter of the inner radial surface of the pourer at the level of the afore-mentioned edge. This guarantees that the skirt of the cap tends to expand the pourer radially as soon as it is positioned inside the pourer, such expansion being produced preferentially at the level of the edge of the neck, which makes it possible to compress the pourer efficiently between the flange and the neck.   The skirt is formed in one piece with the cap, in a material which is harder than the material of the pourer. The one-piece nature of the cap and of the skirt gives them a satisfactory solidity and rigidity while the fact that the material constituting the skirt is harder than that of the pourer, makes it possible to privilege a deformation of the pourer when the skirt bears against the pourer.   The neck, the pourer and the cap are made of plastics material. In that case, the neck and the cap may be provided to be made of high or medium density polyethylene, while the pourer is made of low density polyethylene.       

   The invention also relates to a container for liquid, particularly a plastic bottle equipped with a closure device as described hereinabove. Such a container can be transported without risk of leakages before and after the first use of the fluid that it contains, and may easily be recycled as it does not comprise an aluminum based membrane. The edge of the neck is advantageously sheathed by the inner end of a substantially truncated zone of the neck. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be more readily understood and other advantages thereof will appear more clearly in the light of the following description of a form of embodiment of a closure device according to the invention, given solely by way of example and made with reference to the accompanying drawings, in which: 
       FIG. 1  is a view in perspective of an upper part of a milk bottle according to the invention, equipped with a closure device in accordance with its principle, of which the cap is in a first position. 
       FIG. 2  is a view in perspective similar to  FIG. 1 , while the cap is in a second position. 
       FIG. 3  is a section along line III—III in FIG.  1 . 
       FIG. 4  is a section along line IV—IV in  FIG. 1 , and 
       FIG. 5  is a section on a smaller scale along line V—V in FIG.  2 . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   The bottle shown in the Figures is a bottle intended to contain milk, made by blowing a parison of high density polyethylene. The cost of such a bottle is attractive, while it performs its function of a container efficiently. 
   The neck  2  of this bottle is cylindrical and X 2 -X′ 2  denotes its axis of symmetry. This neck has a curved generatrix and it defines a substantially truncated zone  21  of which the inner end forms the edge  22  of the neck  2 , the zone  21  extending by a first flange  23  extending radially towards the outside with respect to the axis X 2 -X′ 2 . A section  24  joins the flange  23  to a second flange  25 , itself joined by a second section  26  to the principal body  11  of the body  1 . 
   The closure device comprises a pourer  3  and an assembly  4  forming cover made of plastics material. The pourer  3  is molded from low density polyethylene while the assembly  4 , which is in one piece, is molded from high or medium density polyethylene. The assembly  4  is therefore made of a material more rigid than that of the pourer  3 . Other materials may be used for molding the elements  2 ,  3  and  4 , the material of the pourer remaining less rigid than those of the neck  2  and of the assembly  4 . 
   The pourer  3  is cylindrical and symmetrical about an axis X 3 -X′ 3  merged with axis X 2 -X′ 2  when the pourer  3  is mounted on the neck  2 . The pourer  3  comprises a part  31  with substantially rectilinear generatrix of which the edge  32  opposite the body  11  of the bottle  1  is curved outwardly, with the result that it forms a surface  32   e  for flow of the milk without contact with the neck  2 . The part  31  is partially arranged inside the neck  2 . 
   From a median zone of the part  31  there extends radially towards the outside of skirt  33  intended to cover the zone  21  and the flange  23  of the neck  2 , the skirt  33  being provided, at its edge  34  distant from the part  31 , with a catching beard  35 , intended to mesh against a radial surface  23   a  of the flange  23  opposite the part  21 . This allows an immobilization by cooperation of shapes of the pourer  3  of the neck  2 . 
   The bead  35  presents an inner face  35   a  divergent in the direction of the body  11 , with the result that the pourer  3  can be positioned on the neck  2  by elastic clipping by means of an elastic deformation of the skirt  33  when the pourer  3  is pushed on the neck  2  in the direction of the body  11 . 
   A membrane  36  is connected to the part  31  by a zone  36   a  of rupture, this membrane making it possible to isolate the interior volume of the bottle  1  as long as it remains in place. The membrane  36  is secured to a grip ring  37  in which a user can pass a finger to exert a force F 1  directed opposite the body  11  in order to remove this membrane when the milk contained in the bottle is used. 
   The assembly  4  comprises a ring  41  intended to be disposed around the neck  2 , the ring  41  being provided with a catching bead  42  adapted to come into mesh against a lower surface  23   a  of the flange  25 . Lower is understood to mean that the surface  25   a  is oriented downwardly when the bottle  1  is placed on a flat surface, its neck facing upwardly. 
   The ring  41  also contributes to maintaining the skirt  33  in mesh with the flange  23  in position. The ring  41  extends in the direction of the body of the bottle  1  by a ring  43  making it possible to mask the transition part between the neck  2  and the body and the bottle  1 . 
   The inner face  42   a  of the bead  42  is also truncated and divergent in the direction of the body  11 , which makes it possible to envisage an elastic clipping of the ring  41  on the neck  2 . 
   The ring  41  is joined by a hinge  44 , formed by an elastically deformable thinned zone, to a substantially cylindrical cap  45  of which X 45 -X′ 45  denotes the central axis. Before the first use of the bottle  1 , the cap is joined by a band  46  to the ring  41  over virtually the whole of the circumference of this ring, axes X 2 -X′ 2  and X 45 -X′ 45  being merged. The band  46  is respectively joined by two frangible zones  46   a  and  46   b  to the ring  41  and to the cap  45 . A tongue  46   c  makes it possible to remove the ring  46  by rupture of the zones  46   a  and  46   b , which allows a movement of pivoting of the cap  45  around axis X 44 -X′ 44  of the hinge  44  between the positions of  FIGS. 1 and 2 . 
   The hinge  44  may be associated with bistable tongues, which makes it possible to conserve the orientation of the cap  45  in each of the positions shown in  FIGS. 1 and 2 . 
   The cap  45  is equipped with a tongue or “peaked cap”  451  allowing it to be lifted by a force F 2  represented in  FIGS. 3 and 5 . 
   According to the invention, the cap  45  is equipped with a skirt  452  which is cylindrical and centered on axis X 45 -X′ 45 . 
   The skirt  452  extends in the direction of the interior volume of the bottle  1  from the inner surface  453  of the cap  45  which is oriented towards this interior volume. The height H of the skirt  452  measured parallel to axis X 45 -X′ 45  is such that, in the closed position shown in  FIGS. 1 ,  3  and  4 , the lower edge  454  of the skirt  452  is located below the edge  22  of the neck  2 , i.e. towards the interior volume of the bottle  1 . 
   The outer radial surface  455  of the skirt  452  is provided with two flanges, referenced  456  and  457  respectively, which extend radially towards the outside with respect to the surface  455 . The flange  456  is arranged in the vicinity of the edge  454 , with the result that it is located at the level of the edge  22  when the cap  45  is in closed configuration and that it is adapted to exert on the inner radial surface  31   a  of the part  31  a force F 3  centrifugal with respect to axes X 3 -X′ 3  and X 45 -X′ 45  which in that case merge, this force F 3  tending to compress this part  31  against the edge  22 . 
   Such compression is possible due to the difference in hardness between the skirt  452  and the edge  22  of the neck  2 , on the one hand, and that part  31  of the pourer  3 , on the other hand, which is more supple or “softer” than the elements  452  and  22  between which it is compressed. 
   The force F 3  therefore makes it possible to guarantee the tightness on the one hand between the pourer  3  and the neck  2 , i.e. between the part  31  and the edge  22  and, on the other hand, between the pourer  3  and the assembly forming cover  4 , i.e. between the flange  456  and the part  31 . 
   The flange  456  makes it possible to concentrate the force exerted on the part  31  of the pourer  3  at the level of the edge  22 , this further improving the tightness obtained. 
   The outer diameter D 1  of the flange  456  is chosen to be slightly larger than the inner diameter D 2  of the surface  31   a  at the level of the edge  22 , with the result that, by simply positioning the skirt  452  inside the pourer  3 , a force F 3  of sufficient intensity is obtained. In practice, satisfactory results can be obtained with a difference between the diameters D 1  and D 2  included between 0.5 and 1 mm, while these diameters are included between 20 and 40 mm, preferably of the order of 30 mm. 
   The pourer  3 , on the one hand, and the assembly  4  forming cap, on the other hand, are each made in one piece by molding, with the result that they are easy to manipulate and position on the neck  2 . In particular, the fact that the skirt  452  is in one piece with the cap  45  gives it a good rigidity while its cost price is particularly attractive. 
   The invention has been described with an assembly forming a hinged cap. However, it is applicable with a screwed cap.