EP2582584A1

EP2582584A1 - Lightweight container having a reinforced base

Info

Publication number: EP2582584A1
Application number: EP11735502.4A
Authority: EP
Inventors: Wilfried Hermel; Pierrick Protais
Original assignee: Sidel Participations SAS
Current assignee: Sidel Participations SAS
Priority date: 2010-06-18
Filing date: 2011-06-15
Publication date: 2013-04-24
Anticipated expiration: 2031-06-15
Also published as: MX2012014935A; BR112012032143A2; ES2530768T3; FR2961492A1; FR2961492B1; US20130087568A1; CN102971220A; EP2582584B1; US8875921B2; CN102971220B; WO2011157952A1

Abstract

The invention relates to a container made of thermoplastic material, comprising a body that extends between a neck and a base that is able to withstand, without significantly deforming, a hydrostatic pressure caused by the column of a liquid contained in said container, said column of liquid being increased by a pressure not exceeding 2x10⁵ Pa, said base comprising main ribs (70) in the form of grooves that are open towards the outside and extend approximately radially, passing through an annular zone that forms an approximately flat seat (50) by way of which said base (30) can rest in a stable manner on a flat support, said main ribs (70) extending upwards on a wall (80) connecting the base to the body of the container. The container has a shoulder (90) that forms a joining zone between said connecting wall (80) and said body of the container, and said main ribs (70) extend upwards beyond said shoulder (90).

Description

LIGHT CONTAINER WITH REINFORCING BACKGROUND

The present invention relates to improvements made to the bottoms of the containers, in particular to the bottoms of the bottles, made of thermoplastic material such as PET, having a body extending between, above, a neck and, below, a base capable of supporting without significant deformation. the hydrostatic pressure due to the increased liquid column with an overpressure not exceeding about 2 x 10 ⁵ Pa.

Containers intended to contain a flat liquid (for example bottles intended to contain table water) are, in most cases, provided with a domed bottom generally spherical cap with concavity facing outwards and of relatively low height.

Such bottoms are often provided with substantially radially radially extending ribs which are distributed around a central recess, said ribs possibly having various conformations and possibly being able to overflow on the bottom of the wall of the body in order to reinforce the seat (peripheral zone by which the bottom rests on a support).

The height of funds of this kind, including central recess, is typically of the order of 10 mm, and can be up to 15 mm. Such bottoms are shaped to support without deformation the column of flat liquid which overcomes them.

But they do not have sufficient strength to withstand additional stress, which may for example be due to an internal pressure, even low value.

It is known, for containers whose contents must undergo a process of inerting, for example, to equip them funds improved in terms of resistance so that they do not deform under the action of the internal pressure .

For the record, inerting is a process according to which, after filling the container with a liquid and before capping, the air that remains in the container is evacuated so as to best preserve the said liquid. A reinforced bottom of this type which is conventionally used today is illustrated in FIGS. 1A to 1D of the accompanying drawings.

FIG. 1A is a side view of the lower part of a container 1 (in this case a bottle of substantially cylindrical general shape of revolution) of thermoplastic material such as PET, having a body 2 extending between, above, a collar (not visible) and, inferiorly, a bottom 3.

The bottom 3 is shown, alone, in FIG. 1B in bottom view, in FIG. 1C in diametral section along the line IC-I C of FIG. 1B, and in FIG. -Dessous. The bottom 3 comprises a vault 4 of generally domed shape with a concavity turned towards the outside of the container 1 and it has an annular zone 5 surrounding the arch 4 and forming a substantially planar base by which said bottom 3 can rest stably on a plane support.

In its central part, the vault 4 opens on a domed dome 6 also concavity facing outwardly, said dome thus being set back towards the inside of the container with respect to the vault.

Outside the annular zone forming a seat, the bottom 3 is connected to the body 2 of the container by a wall 8, also called connecting wall 8. Several main ribs 7 open towards the outside, in the general shape of gutters with substantially parallel edges and of substantially constant depth, extend radially in a star shape from the wall 8 to the dome 6 in which they terminate, crossing the zone Annular forming a seat and the roof 4; in the illustrated example, the main ribs 7 are odd, here equal to five.

To improve the mechanical strength of the bottom, it is added secondary ribs 10, which may have substantially the same conformation as the main ribs 7, which are interposed between the main ribs 7, but extend radially in a star from the wall 8 only to the middle of the vault 4, crossing the annular zone 5 forming a seat. It will be noted that all the ribs, both the main ribs 7 and the secondary ribs 10, are hollowed out in the arch 4, which has a smooth annular conformation only cut by the ribs as is clearly apparent in FIGS. 1A to 1D. Manufacturers of thermoplastic containers such as PET are constantly seeking relief of the containers, which results, inter alia, in lightening the bottoms of the containers. As a result, container bottoms having forms which were satisfactory a few years ago can no longer be suitable because of the substantial reduction in the quantity of material used.

Thus it has been found, with experience, that a reinforced bottom arranged as explained above could no longer be satisfactory, in its lighter version, even for overpressures of only about 1 x 10 ⁵ Pa.

To further reinforce the rigidity of the bottom of such a container, the document FR 2 932 458 recommends producing claw-shaped areas on the roof 4, around the annular zone 5 forming a seat.

The document FR 2 932 458 also recommends varying the depth of the primary nerves, the depth to be maximum approximately to the right of the annular zone 5 forming a seat.

The object of the present invention is to propose a variant of embodiment more advantageous than that recommended in FR 2 932 458. In fact, it makes it possible to combine the effect of the ribs with a strengthening effect of the bottom of the container.

Document FR 2 926 035 discloses funds for light containers which comprise a shoulder between a first part of the bottom of the bottle forming the seat of the latter and a second part ending the body of the container in the lower part of the latter (part considered inferior when the container has its neck pointing upwards).

Such a bottom of the container has the disadvantage of not preventing a swiveling phenomenon, that is to say a phenomenon according to which, when the container is placed on a flat surface, the axis of the container tilts with respect to a vertical axis (because of the low weight of the container) and the container rotates about a theoretical vertical axis, straightening its axis, until it stops alone, when its axis is placed in the theoretical vertical axis.

The invention also aims to overcome this drawback.

It concerns for this purpose a thermoplastic container, comprising a body connected to a bottom adapted to withstand without significant deformation a hydrostatic pressure due to the column of a liquid contained in said container, the liquid column being increased by a pressure not exceeding 2x10 ⁵ Pa, the bottom comprising main ribs in the form of outwardly open grooves of substantially radial extent passing through an annular zone forming a substantially planar base by which said bottom may rest stably on a support plane, the main ribs being distributed in star on the bottom and going up on a connecting wall of the bottom with the body of the container. The container according to the invention is remarkable in that it comprises a shoulder forming a connecting zone between the connecting wall and the body of the container, and in that said main ribs go up beyond said shoulder on the wall of the container. connection.

The combination of the shoulder with radial ribs which intersect the said shoulder ensures a better rigidity at the bottom of the container and overcomes the problem of swiveling explained above.

Indeed, on the one hand, the shoulder contributes to enhance the effect of the vertical ribs that cross, the vertical ribs opposing a crushing phenomenon of the bottom of the container under the action of the weight of the liquid that it contains, the shoulder not allowing bellows movement in a vertical direction of the bottom of the container. On the other hand, the protruding ribs which are distributed in a star on the bottom prevent the swiveling phenomenon, and their "anti-swiveling" effect is also reinforced because they cross the shoulder. The invention may also include the following features, taken separately or in combination: - the background may include:

a concave concavity vault turned towards the outside of the container and

- a dome protruding inwardly of the container, and concavity turned outward, opening in the center of the vault,

- The main ribs extending radially on the vault from the seat to the dome.

- The bottom may also comprise secondary radial ribs which are interposed between the main ribs and which extend radially in a star on the connecting wall and through the seat until substantially the birth of the vault;

- The secondary ribs can extend on the connecting wall and up beyond the shoulder, at a level substantially identical to that of the main ribs;

- According to a first embodiment, the bottom may comprise a number of main ribs uniformly distributed and the same number of secondary ribs uniformly distributed and each interposed between two adjacent main ribs;

- According to a second embodiment, the bottom may comprise between six and twelve main ribs distributed uniformly and between six and twelve secondary ribs each interposed between two main ribs;

- According to yet another embodiment, the bottom may comprise a number of main ribs distributed uniformly and the same number of identical sets of several secondary ribs uniformly distributed and each interposed between two adjacent main ribs;

- In the case of this embodiment, it may be provided that the bottom comprises four main ribs distributed uniformly and four sets of three secondary ribs each interposed between two consecutive main ribs; in another variant embodiment, it is possible to provide that the bottom comprises five main ribs uniformly distributed and five sets of two secondary ribs each interposed between two consecutive main ribs;

according to an embodiment which will be described and illustrated later, the secondary ribs may have a regular depth on the connecting wall, between the seat and the shoulder;

- In addition, the main ribs may have a depth that decreases between the seat and the shoulder;

- The main ribs can also have a regular depth on the vault;

- In addition, said main ribs may have, in the vicinity of the dome, a flared end so that a flared end of a main rib joins a flared end of an adjacent main rib, the flared ends forming a sun design around dome;

- In addition, the main ribs can flare regularly on the vault, from the seat to the vicinity of the dome;

the "anti-swiveling" effects have been noted for the embodiments, according to which the main ribs go up beyond the shoulder on the body of the container at a height of substantially between 1 and 5 mm, preferably between 1 and 2 mm;

in the context of advantageous embodiments, the container may have a capacity of substantially 0.5 L and a weight of substantially 7 g.

To be able to be executed, the invention is set forth in a sufficiently clear and complete manner in the following description which is, in addition, accompanied by drawings in which:

FIG. 1A is a side view of the lower part of a container (here a bottle of general shape substantially cylindrical of revolution) in thermoplastic material such as PET, arranged according to the state of the art;

- Figures 1 B to 1 D respectively show in bottom view, in diametral section along the line IC-IC of Figure 1 B, and in perspective from below, the sole bottom of the container shown in Figure 1A;

- Figure 2 illustrates a bottom of a container according to the invention in side view;

- Figure 3 shows the bottom of Figure 2 in view from below and in perspective;

- Figure 4 is a bottom view of the bottom shown in Figure 2;

- Figure 5 is a sectional view along the V-V plane shown in Figure 4;

- Figure 6 is a sectional view along the plane VI-VI shown in Figure 4;

- Figures 7 and 8 illustrate, schematically, in bottom view two variants of a bottom of a container according to the invention.

In the following description, the terms "lower", "upper", "high", "low" etc. are used with reference to the drawings for greater ease of understanding. They should not be understood as limitations of the scope of the invention.

Reference will be made to FIGS. 2 to 6 to describe a preferred embodiment of the invention. Indeed, Figures 1A to 1D show a container bottom according to the state of the art.

Figure 2 shows a bottom 30 of a container according to the invention.

The bottom 30 is also shown in Figures 3 and 4, seen from below. The bottom 30 may be obtained by molding, as known to those skilled in the art.

The bottom 30 comprises ribs 70, said main ribs 70, each in the form of an outwardly open groove of substantially radial extent, passing through an annular zone forming a substantially flat seat 50, through which the bottom can rest stably. on a flat support.

The main ribs 70 back on a wall 80, connecting the bottom 30 with the body 20 of the container (see Figure 2).

It can also be seen in FIGS. 3 and 4 that the bottom comprises, as is itself known, a concave arch 40 concavely facing the outside of the container (like the arch 4 illustrated in FIGS. 1C and 1D of FIG. container of the state of the art).

The bottom 30 of the container according to the invention also comprises a dome 60 projecting towards the inside of the container and concavity facing outwards, opening at the center of the vault 40.

Note especially in Figures 3 and 4 that the main ribs 70 extend radially on the roof 40, from the seat 50 to the dome 60.

On the side of the bottom 30 of the container according to the invention, the main ribs 70 back on the wall 80 of connection to the body 20 of the container and through a shoulder 90 formed on the periphery of the container.

In other words, the main ribs 70 go up past said shoulder 90 made on the periphery of the container.

The shoulder 90 forms a connecting zone between the connecting wall 80 and the body 20 of the container.

The shoulder 90 is made by a sudden change in diameter between the connecting wall 80 and the body 20 of the container.

This abrupt change in diameter can be achieved by a steep slope connecting the connecting wall 80 and the body 20 of the container. The connection between the wall 80 and the shoulder 90, as well as between the shoulder 90 and the body 20 are made by sharp edges.

Thus, the shoulder 90 prevents deformation of the bottom of the container, for example, a flare of the bottom under the action of the weight of the liquid column contained in the container. It also prevents any movement of the accordion movement type of the bottom of the container relative to the body 20 of the container.

Also, the shoulder 90 is a reinforcement that prevents the bottom from being deformed.

The main ribs 70 have a particular profile, as can be seen in particular in FIGS. 3 and 4.

In particular, the main ribs 70 have a width that increases regularly between the seat 50 and the dome 60. In other words, the main ribs 70 flare regularly on the roof 40 defined between the seat 50 and the dome 60 It is noted in particular that the end 71, located in the vicinity of the dome 60, of each main rib 70 is sufficiently flared so that the flared end 71 of a main rib 70 joins the end 71 flared with a main rib 70 adjacent.

The flared ends 71 thus form a sun pattern around the dome 60. The sun design of the ribs 70 around the dome helps to limit the swiveling effect defined above. In addition, the anti-swiveling effect of the drawing in sun is increased when it is combined with the fact that the main ribs 70 cross the shoulder 90.

As can be seen in the figures, in the context of this embodiment of the bottom of the container according to the invention, the bottom 30 also comprises secondary ribs 100, radial, which are interposed between said main ribs 70 and which also extend radially in a star on the wall 80 of connection, and pass through the seat 50 until substantially the birth of the vault 40. It will be understood by "birth of the vault" the portion of the vault 40 which connects to the sitting 50. The secondary ribs 100 extend over the connecting wall 80, also going up beyond said shoulder 90, at a level substantially identical to that of the main ribs 70.

In the example shown, the bottom 30 comprises a number of main ribs 70 distributed uniformly and the same number of secondary ribs 100 distributed uniformly and each interposed between two adjacent main ribs 70.

In the embodiment illustrated in FIGS. 2 to 6, the bottom 30 comprises an alternation of eight main ribs 70 and eight secondary ribs 100.

In general, the container according to the invention could comprise between six and twelve main ribs 70 uniformly distributed on its bottom 30, and as many secondary ribs 100 each interposed between two adjacent main ribs 70. It should be understood that the invention is not however limited to this embodiment.

Indeed, as illustrated schematically in a bottom view in Figures 7 and 8, it could be provided that the bottom 30 has different arrangements of main ribs 70 and secondary ribs 100. Thus, one could predict that the bottom 30 has a number main ribs 70 distributed uniformly and the same number of identical sets of several secondary ribs 100 uniformly distributed and each interposed between two adjacent main ribs 70. In the context of an embodiment, as illustrated in FIG. 7, with four main ribs 70 uniformly distributed over the bottom 30, it would be possible, for example, to provide four identical sets of three secondary ribs 100, each interposed between two ribs. main 70 consecutive.

In a variant illustrated in Figure 8, the bottom could comprise five main ribs 70 distributed uniformly on the bottom 30, and five sets of two secondary ribs interposed between two consecutive main ribs 70, without departing from the scope of the invention. In the context of the illustrated embodiment, the bottom 30 is intended for a container having a capacity of substantially 0.5 liter and a weight of substantially 7 grams.

In the context of this embodiment, again, the main and secondary ribs 70 and 100 rise back past the shoulder 90 on the body 20 at a height of substantially between 1 and 5 mm and preferably between 1 and 2 mm. It is with these dimensions that the swiveling effect is most attenuated when the embodiment is applied to a container of this capacity. Reference will now be made to FIGS. 5 and 6 to describe the profile of the main and secondary ribs 70 made in the bottom 30.

In FIG. 5 are shown, in sectional view, secondary ribs 100. It is noted that the secondary ribs 100 extend well on the wall 80, providing the connection between said bottom 30 and the body 20 of the container.

It is also noted that the secondary ribs 100 cross the seat 50 until the birth 41 of the roof 40, that is to say the part of the roof 40 which is close to the seat 50.

The secondary ribs 100 have a regular depth between the seat 50 and the shoulder 90.

Beyond the shoulder 90, so in their part closest to the body 20 of the container, the secondary ribs 100 have an end 101 whose depth is decreasing.

In FIGS. 2 and 3, it can be seen that the end 101 of the secondary rib 100 has a width which is first increasing (the largest width carrying the reference 102) from the shoulder 90, then decreasing, of so as to substantially have an arrow shape facing upwardly of the container.

The main ribs 70 are shown in Figure 6. They have a depth that decreases between the seat 50 and the shoulder 90. The end 72 of each main rib 70, which is located above the shoulder 90, therefore the one which is closest to the body 20 of the container, has a shape substantially identical to that of the end 101 of the secondary ribs 100 which have been previously described, as can be seen in particular in Figures 2 and 3.

The main ribs 70 also have a regular depth on the roof 40, as shown in FIG.

As can also be seen, the flared end 71 of the main ribs 70 ends substantially at the foot of the dome 60. The main ribs 70 do not therefore impinge on the dome 60, the encroachment of the main ribs 70 on the dome 60 being known from the state of the art, as shown in FIG.

Thus realized, the main ribs 70, due to their particular shape and the fact that they cross the shoulder 90, prevent the bottom swiveling effect, when placing the bottom of the container on a flat surface, for example.

The foregoing description clearly explains how the ribs and the shoulder according to the invention are made to avoid any swiveling phenomenon and also to strengthen the bottom of a particularly light container, since such a container may have a weight which is next to seven grams.

It should be understood, however, that the invention is not specifically limited to the embodiments that have been presented.

On the contrary, the invention extends to the production of any equivalent means.

Claims

1. Container (1) made of thermoplastic material, comprising a body

(20) connected to a bottom (30) adapted to withstand without significant deformation a hydrostatic pressure due to the column of a liquid contained in said container, said liquid column being increased by a pressure not exceeding 2x10 ⁵ Pa, said bottom (30) comprising main ribs (70) in the form of outwardly open grooves of substantially radial extent passing through an annular area forming a substantially planar seat (50) through which said bottom (30) can rest stable on a flat support, said main ribs (70) being distributed in a star on the bottom (30) and up on a wall (80) connecting the bottom (30) with the body (20) of the container, characterized in that it comprises a shoulder (90) forming a connection zone between said connecting wall (80) and the body (20) of the container, and in that said main ribs (70) go up beyond said shoulder (90) on the wall (80) of connection.

Container according to claim 1, characterized in that said bottom (30) comprises:

a concavely concave arch (40) facing outwardly of the container and

- a dome (60) projecting towards the inside of the container, and concavity facing outwards, opening at the center of said arch (40),

- said main ribs (70) extending radially on said arch (40) from the seat (50) to the dome (60).

Container according to claim 2, characterized in that said bottom (30) comprises secondary ribs (100), radial, which are interposed between said main ribs (70) and which extend radially in a star on the wall (80) of connection and pass through the seat (50) to substantially the birth (41) of the arch (40).

Container according to claim 3, characterized in that said secondary ribs (100) extend over said connecting wall (80) and rise beyond said shoulder (90) at a level substantially identical to that of said main ribs ( 70).

Container according to claim 3 or 4, characterized in that the bottom (30) comprises a number of main ribs (70) uniformly distributed and the same number of secondary ribs (100) uniformly distributed and each interposed between two main ribs (70) adjacent.

Container according to claim 5, characterized in that the bottom (30) comprises between six and twelve main ribs (70) distributed uniformly and between six and twelve secondary ribs (100) each interposed between two main ribs (70).

Container according to claim 3 or 4, characterized in that the bottom (30) comprises a number of main ribs (70) uniformly distributed and the same number of identical sets of several secondary ribs (100) uniformly distributed and each interposed between two main ribs (70) adjacent. Container according to claim 7, characterized in that the bottom (30) comprises four main ribs (70) distributed uniformly and four sets of three secondary ribs (100) each interposed between two consecutive main ribs (70).

Container according to claim 7, characterized in that the bottom (30) comprises five main ribs (70) distributed uniformly and five sets of two secondary ribs (100) each interposed between two consecutive main ribs (70).

Container according to any one of claims 3 to 9, characterized in that the secondary ribs (100) have a regular depth on the wall (80) of connection, between the seat (50) and the shoulder (90).

Container according to any one of claims 3 to 9, characterized in that said main ribs (70) have a depth which decreases between the seat (50) and the shoulder (90).

Container according to any one of the preceding claims, characterized in that said main ribs (70) have a regular depth on the roof (40).

Container according to any one of claims 2 to 12, characterized in that said main ribs (70) have in the vicinity of the dome (60) an end (71) flared so that one end (71) flared with a rib main (70) joins one flared end (71) of an adjacent main rib (70), the flared ends (71) forming a sun pattern around the dome (60).

Container according to claim 13, characterized in that the main ribs (70) regularly flare on the roof (40), from the seat (50) to the vicinity of the dome (60).

Container according to any one of the preceding claims, characterized in that said main ribs (70) go up beyond said shoulder (90) on the body (20) of the container at a height of substantially between 1 and 5 mm, preferably between 1 and 2 mm.

Container according to any one of the preceding claims, characterized in that the container has a capacity of substantially 0.5 L and a weight of substantially 7 g.