Method for mounting a bottom on a container

The present invention relates to a setting method instead of the bottom of a package comprising a tubular body non-round cross-section of section non-round cross closed by a lid and containing the product to be packaged, said bottom having the form of a cup whose dimensions correspond to the cross section of the tubular body, the cuvette being fixed after its introduction, by means of a tool male, in the body by activation of an adhesive and folding the edge of the tubular body.

In the patent application EP-A-0668151 of the applicant is proposed a method of manufacturing a tubular package preferably made of a recyclable material such as paper or cardboard of which the lid and the bottom are made of a material at least similar. After attaching the lid and the possible tamper evident membrane, packaging is filled with the product to be packaged and sets the background. The bottom is a cuvette having the dimensions and shape of the cross section of the tubular body and is introduced inside the body with the tool male. However, upon introduction of the basin which rubs against the inner circumference of tubular body the air that is expelled by the movement said cup has trouble out what is delays the process of introducing and finally the fixing of the bottom, or it creates a positive pressure inside packaging which is not desired. On the contrary, we want to leave, after the sealing of the packaging, subsist a negative pressure inside of the package. This negative pressure makes it possible, hand, better conservation of the packaged product and, secondly, in case of packaging of heating to avoid the creation of an overpressure within packaging that could lead to the destruction of his seal.

different methods have been proposed to allow to evacuate this air, in particular using a pressure source negative to evacuate and thus allow the in place of the bowl. This way of doing this disadvantages, because depending on the shape of the section of the tubular body, it is sometimes difficult to obtain a perfect seal when setting under negative pressure and results in variations internal pressure can affect the seal of packaging.

The present invention aims to provide a method to overcome these disadvantages by means Simple.

The method according to the invention is characterized in that one proceeds according to the following steps:<sl><li>a) inserting the open end of the tubular body between two fixed opposed jaws fit design two opposite end parts of the tubular body, and the distance between the two jaws being less than the distance between said opposed parts so that the portions not clamped in said jaws not undergo permanent deformation moving away from one another;</li><li>b) is placed the bottom by means of a punch, said are being maintained at its final position by said fixed jaws and the punch; </li><li>c) clamp two opposite regions of the lateral surface of the tubular body by two clamping bodies located below two movable jaws for to act on the portions of the free end of the body tubular not gripped by the fixed jaws for hunt at least partially the air in the tubular body;</li><li>d) tightening the movable jaws for contacting the entire inner edge of the free end of the tubular body with the bowl;</li><li>e) conducting the activation of the adhesive film, and the following the release of the closed package.</li></sl>

The advantage of the present invention resides in the fact that by using simple ways to apply opposing forces on diametrically opposed surfaces packaging, a deformation of the edge is obtained of sufficient packing to allow the introduction of the bowl while allowing to discharge the air removed by the introduction, between the edge of the bowl and the deformed edge of the package. It is clear that the method is applicable to a package allowing slight elastic deformation. In addition, one obtains partial evacuation of the air contained in the package by squeezing the sides of the tubular body.

It is of course expected that the deformations to which the package is subjected remain in the field of the elasticity of the material to avoid damage of the package.

According to an alternative embodiment, if the packaging section is rectangular fixed jaws act on the narrow sides of the surface of the tubular body.

According to another embodiment, the section of packaging is elliptical and stationary jaws grip regions on either side of the ends the major axis of the ellipse.

According to another embodiment, the section has a semicircular shape and the fixed jaws grip regions at the ends of the rope.

Finally, according to another variant of execution and to accelerate the process of implementation of the background, we equip the forming die of the bowl Background of suction ducts for the evacuation rapid air driven by the introduction of the background in the tubular body.

The invention will be described in more detail using the accompanying drawing<sl><li>Figure 1 is a top view of the tubular body of a packaging with the jaws.</li><li>Figure 2 is a side view.</li><li>Figure 3 is a side view of a variant execution.</li></sl>

A package 1 of substantially rectangular section, whose one end is already closed by a cover and optionally a sealing membrane and already containing the product to be packaged is introduced between two jaws M1, M2 fixed with surfaces corresponding to the shape and dimensions of the surface side of two portions 2, 3 opposed to the package 1. In this case, the selection is focused on the two faces having the smallest area. he is necessary that the jaws M1, M2 espouse said faces, because the spacing between the jaws is less than the spacing of the faces 2, 3 of the package so as to obtain the distance between the two other sides 4, 5 of the edge of the package.

By means of a punch P having the shape of the cuvette 6 which will form the background, this bowl is placed between M1 and M2 jaws, the bowl being and in its final position. Thereafter to means of two clamping elements S1 and S2 is applied antagonistic forces F3 and F4 against the two portions opposite to the side surface of the package 1 and particularly in areas under two jaws mobile M3 and M4. This clamping effect is to expel at least some of the air out again in the tubular body 1. Thereafter, while maintaining S3 clamping forces, S4 we compare two M3 and M4 jaws by applying forces F1 and F2 to press the edges 4 and 5 of the package against the corresponding edge of the bowl 6. From that moment, the adhesive film is activated by heating or by high frequency or by other similar means thus obtaining sealing the bottom edge of the body tube 1. Subsequently releasing the forces F1, F2, F3 and F4, and packaging finds its final form since the forces F3, F4 and the spacing M1 and M2 are provided jaws to cause deformation nonpermanent packaging.

Whatever the shape of the cross section, other than round, the method can be used with success.

Thereafter, the package continues its manufacturing cycle as provided in the aforementioned patent of the same applicant (hemming ...).

Thus, by a simple method we reach to Place a cup having the final form without the air in the package brake setting Place this bowl because it can move in the displacement of the bowl by the space between the deformed edge 4 and 5 (drawn in phantom in Figure 1), the cell and subsequently one arrives to still chase an additional part air using the S1 and S2 clamping members.

In order to be able to proceed at a rate very high of setting Placed the bottom 6 of the package 1, was provided with the forming die 7 of the bottom of the bowl described in the aforementioned patent application of the same inventor, channels 8 connected to a vacuum source (Not shown). Thus, during the establishment of the background by the punch P, the air expelled is drawn through the channels 8, and any particles of the packed product thus avoiding contamination of the forming die 7. To the Otherwise, the procedure is identical to what has been described previously.