EP1257474B1 - Plastic container with non-cylindrical body reinforced with peripheral grooves - Google Patents

Abstract

The invention concerns improvements to containers, in particular plastic bottles, having a body (2) with a circular non-cylindrical wall, so as to reinforce them and prevent cross-section variation when they are subjected to compression forces. Part at least of the wall is provided with a substantially planar relief. The wall is reinforced with peripheral grooves (26, 27, 28, 29, 30) oriented in planes substantially perpendicular to the longitudinal axis (X) of the container, and the part including a substantially planar relief is run through with several grooves. The width of each of the grooves is such that it is less wide (L2) where it emerges in the part of the wall than at the middle (L1) of its crossing. The invention is particularly useful for reinforcing large capacity bottles.

Description

The subject of the invention is improvements to containers made of plastic material whose body, not cylindrical of revolution, is reinforced by means of reinforcement, constituted by grooves peripheral devices. It can be applied to any type of container whose body has at least part of the wall with a substantially planar relief, this which is the case with vials. It still applies, and in particular, bottles whose body has a generally shaped section quadrilateral, with rounded angles and intended to receive a so-called flat content, that is to say without internal pressure.

Throughout the text of this application, the relative terms to a spatial position of a container or various parts of a container relatively to each other must be understood when the container is upright, i.e. oriented vertically along its axis longitudinal, with the bottom at the bottom and the collar at the top. So this is worth in particular but not exclusively, for the terms above, below, lower, upper, up, down, height, vertical, horizontal, etc.

It is known that plastic containers are increasingly lighter, which creates problems for good resistance mechanical of these containers both in the longitudinal and transverse directions.

So when taken in hand, mainly after their opening, they tend to crash, which may cause projection of their content, especially when it is liquid.

When the containers are closed, compressive forces occur manifest when stacked on top of each other for their storage or transport. If their walls are not enough rigid, this results in a tendency to increase the cross-section of the body of each container while supporting others: this is due to pressure exerted on a container causes sagging shoulders which increases pressure internal container, which then affects the internal walls. If the containers are attached to each other, the risk is then that, following at the increase in section, the stresses exerted between two containers neighbors become excessive, which can lead to deterioration mutual by stamping for example.

These drawbacks have been partially remedied by making receptacles comprising a succession of reinforcement grooves at the periphery of their body see for example FR 1 397 037 A. However, this solution, if it turns out generally satisfactory for containers with a section body cylindrical, both when handled after opening and when are stacked, not fully stacked for containers with bodies has at least one wall portion with a substantially planar relief, like containers whose body has a cross section of general shape quadrilateral, with rounded angles, especially when they are stacked: we sometimes see a notable increase in their section, by deformation towards the outside of the parts of flat walls between two successive grooves.

The phenomena are all the more marked as the internal volume containers is high (several liters) and / or that the pressure hydrostatic exerted by their content is important. In fact, when forces due to hydrostatic or other pressure tending to increase the section of the walls of a container are present, they tend to exercise more in the center of flat or substantially flat areas only on their edges. This explains the outward deformations of the parts of walls between two successive grooves that can be thus observe on these known containers.

The invention aims to remedy these drawbacks.

According to the invention, a plastic container, having a body oriented along a longitudinal axis, with a non-cylindrical wall of revolution surrounding this axis, the wall being reinforced with grooves peripherals oriented along planes substantially perpendicular to the said longitudinal axis, at least part of said wall having a substantially planar relief and being crossed by several grooves, is characterized in that the width of each groove passing through the part of wall having a substantially planar relief is variable, the variation of width of each of said grooves being such that it is less wide at its outlet in the said part of the wall only in the middle of its crossing.

It can be seen that this particular structure makes it possible to avoid noticeable outward deformations of parts of walls, substantially flat, between two successive grooves.

According to another characteristic, the projection, on its plane orientation substantially perpendicular to said longitudinal axis, from the bottom of a groove passing through a wall part having a relief substantially planar, at least along the crossing, a profile curved, with a concavity turned towards the outside of the wall.

This particular shape gives greater rigidity to the bottoms grooves, which limits the deformations they undergo during resumption of efforts.

According to another characteristic, the walls of the grooves have a curved profile.

This avoids creating angular areas, which may break under stress, due to pressure, shock or other phenomena.

• la figure 1, une vue en élévation d'un mode de réalisation d'une bouteille à section quadrilatérale, constituant un type de récipient auquel est applicable la présente invention ;
• la figure 2, une vue angulaire de la bouteille de la figure 1 ;
• la figure 3, une vue en perspective, légèrement plongeante de la bouteille représentée sur les figures 1 et 2 ;
• la figure 4, une vue en coupe selon la ligne AA de la bouteille représentée sur la figure 1 ;
• la figure 5, une vue en coupe selon la ligne BB de la bouteille représentée sur la figure 2 ;
• les figures 6 et 7, des vues en coupe respectivement selon les lignes CC et DD de la bouteille représentée sur la figure 1.

Other characteristics and advantages of the invention will appear on reading the description of the figures below which respectively illustrate:

• Figure 1, an elevational view of an embodiment of a bottle with a quadrilateral section, constituting a type of container to which the present invention is applicable;
• Figure 2, an angular view of the bottle of Figure 1;
• Figure 3, a slightly dipping perspective view of the bottle shown in Figures 1 and 2;
• Figure 4, a sectional view along line AA of the bottle shown in Figure 1;
• Figure 5, a sectional view along line BB of the bottle shown in Figure 2;
• FIGS. 6 and 7, sectional views respectively along lines CC and DD of the bottle shown in FIG. 1.

The bottle, of longitudinal axis X, shown in FIGS. 1 to 5, includes a neck 1, a body 2, a bottom 3, and an intermediate part, also called shoulder 4, between the body and the neck.

As is known, in the example illustrated, the neck ends in a thread 5, allowing the screwing of a threaded plug.

In the example illustrated, the body 2 of the bottle has a section of general quadrilateral shape, square in this example, with rounded corners, so that the body wall is made up of substantially flat panel-shaped parts, two of which 21,22, are visible in Figure 3, connected to each other by parts of angles rounded, three of which 23, 24, 25 are visible on the same figure 3.

As can be seen more particularly in FIGS. 1 to 3, the wall is reinforced with peripheral grooves 26, 27, 28, 29, 30, all substantially oriented along planes perpendicular to the axis longitudinal. Each throat therefore surrounds the body by crossing the different substantially planar panels 21, 22 and parts of angles 23, 24, 25 rounded. As a result, the wall, in a vertical direction, is consisting of alternating wall sections 31, 32, 33, 34, 35, 36 having the above-mentioned section of general quadrilateral shape, with rounded corners, and peripheral grooves.

According to the invention, the peripheral grooves have a width variation at least in their crossing of a wall part having a substantially planar relief. In the case of the illustrated bottle in the figures, it is therefore at least in their crossing of each of the panels 21, 22, as the width varies, and the variation in width of each of the gorges is such that it is narrower at its outlets in a sign that in the middle of its crossing.

Thus, with the bottle illustrated in Figures 1 to 7, which has four flat panels, each groove has at least four variations of width.

Furthermore, with reference to FIG. 1, which is a view in elevation of the bottle, on the side of a substantially flat panel, notes, for example, that the groove 26 has a width L1, in the middle from its crossing of the panel, greater than its width L2, to each of its outlets in the said panel.

Each of the other gorges has the same characteristics, from so that the flat portions of sections 31, 32, 33, 34, 35, 36 limited by the grooves have a smaller width where that of the grooves is superior, and vice versa.

In other words, two successive gorges crossing said part of substantially flat wall, a panel in the case of the illustrated bottle in the figures, are separated by a section of panel whose width evolves unlike that of the gorges, that is to say that this section is narrower in the middle than on its sides, at the mouth of the gorges. In other words, two neighboring gorges are closer to each other at in the middle of their crossing of a panel than at their outlet in it.

• au milieu de la traversée, les zones planes, ici les tronçons de panneaux 31 , 32, 33, 34, 35, 36, en raison de leur réduction de largeur à cet endroit offrent une surface limitée aux contraintes, alors que la surface offerte par le fond des gorges 26, 27, 28, 29, 30, à cet endroit est supérieure, de sorte que les efforts de déformation sont repris par le fond des gorges. Ce dernier peut se déformer, mais la déformation ne dépasse pas le plan passant par les zones planes situées de part et d'autre de la gorge ;
• sur les bords, donc au débouché des gorges, là où la surface offerte par une portion de zone plane entre deux gorges successives est supérieure, l'absence de déformation s'explique en partie, d'une part, parce que les contraintes qui existent en cet endroit y sont moindres et, d'autre part, par un effet d'arcboutement procuré par les bords des gorges de part et d'autre de la dite portion de zone plane.

It is explained that this particular structure makes it possible to avoid significant deformations towards the outside of parts of walls, substantially planar, comprised between two successive grooves in particular in the following manner:

• in the middle of the crossing, the flat areas, here the sections of panels 31, 32, 33, 34, 35, 36, due to their reduction in width at this location, offer an area limited to constraints, while the area offered by the bottom of the grooves 26, 27, 28, 29, 30, at this location is greater, so that the deformation forces are taken up by the bottom of the grooves. The latter can deform, but the deformation does not exceed the plane passing through the flat zones located on either side of the groove;
• on the edges, therefore at the outlet of the grooves, where the surface offered by a portion of flat area between two successive grooves is greater, the absence of deformation is partly explained, on the one hand, because the constraints that exist in this place are less and, on the other hand, by an arcboutement effect provided by the edges of the grooves on either side of said portion of flat area.

In the example illustrated by the figures, the successive grooves all have the same width variations, on the one hand, and similar or identical dimensions, on the other hand. However, it should be noted that identity is not necessary, the main thing being that in the middle of their crossing a flat part, the width of each groove is greater, and that of each flat portion of a section is the lowest.

In the embodiment illustrated by the figures, with reference to in Figures 2 and 3, in particular, it can be seen that the width of the groove continues to decrease to reach a value L3 lower than L2 in the middle of its crossing of the rounded corner part 23. Note, however, that this provision is not essential either, and that the width of the throat could remain constant and keep the L2 value during this crossing.

It will also be noted that the profile of the walls of each groove is consisting of alternating curves or sinuosities. So we avoid to create sharp angles which are as many zones of incipient fractures.

In Figure 4, which is a sectional view AA of Figure 1, we note that the bottom of the gorges, in the middle of the panels 21, 37, is sufficiently distant from the planes P1, P2, materialized by lines discontinuous, of the panels, so that if forces tend to push back the bottom of the grooves towards the outside, when these take up the forces, it is unlikely that the deformation will become such that the bottoms emerge from the limits of the planes P1, P2.

Figure 5, which is a sectional view BB of Figure 2, shows that at right rounded corners, the width of the grooves is less. However, at the constraints are generally less than in the middle of so the risks of section increase at this level are almost nonexistent.

Figure 6, which is a sectional view CC of Figure 1, that is to say a central section of the bottom of a groove 29, illustrates an embodiment preferred profile of the bottom of the grooves which gives them a more high rigidity and to limit the deformations which they undergo during the resumption of efforts. According to this embodiment, the projection, on their orientation plane substantially perpendicular to the X axis longitudinal, from the bottom of the gorges present, at least along the crossing parts in the form of substantially flat panels, a curved profile, with a concavity turned towards the outside of the wall.

Figure 7, finally, shows, in section DD of Figure 1, a section central section of a wall section 33 having the aforementioned cross section general quadrilateral, with rounded angles and flat parts.

The bottle according to the invention can be obtained by the so-called processes injection blow molding, i.e. those in which a preform in plastic material, previously obtained by injection, is packaged thermally, then blown, alternately stretched then blown, in a finishing mold.

It can also be obtained by extrusion-blowing a parison tubular.

Claims (6)

1. Container, particularly a bottle, made of plastic, having a body (2) directed along a longitudinal axis (X) with a wall not cylindrical of revolution surrounding this axis, the wall being reinforced with peripheral grooves (26, 27, 28, 29, 30) directed in planes roughly perpendicular to the said longitudinal axis, at least part (21, 22) of the said wall having a roughly planar relief and having several grooves running across it, is characterized in that the width of each groove running across the part of the wall exhibiting a roughly planar relief varies, the variation in width of each of the said grooves being such that it has less width (L2) where it opens onto the said wall part than it does (L1) at the middle of its run.
2. Container according to Claim 1, characterized in that the bottom of a groove (29) running across a wall part having a roughly planar relief (21, 22) exhibits, at least along the run across this part, a curved profile, with the concave side facing towards the outside of the wall.
3. Container according to either of Claims 1 and 2, characterized in that the profile of the walls of each groove consists of an alternation of curves or waves.
4. Container according to one of Claims 1 to 3, characterized in that the body (2) has a roughly quadrilateral shape, with rounded corners, so that the wall of the body consists of parts in the form of panels (21, 22), that are roughly planar, connected to one another by rounded corner parts (23, 24, 25), and the peripheral grooves (26, 27, 28, 29, 30) exhibit a variation in width as they run across a panel (21, 22) and the variation in width of each of the grooves is such that it has less width at each of its openings into a panel than it does at the middle of its run.
5. Container according to Claim 4, characterized in that the width (L3) of a groove at the middle of its run round a rounded corner part (23) is less than its width (L2) at its openings into panels.
6. Container according to Claim 4, characterized in that the width (L3) of a groove at the middle of its run round a rounded corner part (23) is equal to its width (L2) at its openings into panels.

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