EP0953508A1

EP0953508A1 - Container

Info

Publication number: EP0953508A1
Application number: EP99201188A
Authority: EP
Inventors: Peter Heijink
Original assignee: FUSION KUNSTSTOFFEN BV
Current assignee: FUSION KUNSTSTOFFEN BV
Priority date: 1998-04-28
Filing date: 1999-04-16
Publication date: 1999-11-03
Also published as: NL1009023C2

Abstract

A container (1) comprising a wall (5) provided with a profile in order to prevent said wall from bending outwards, wherein the profile is at least partially closed. In a preferred embodiment, the profile is formed by at least one, at least substantially U-shaped wall part (7) extending inwards from the wall at the location of two opposed wall edges, seen in horizontal cross-sectional view of the wall, which wall part is closed in at least one place by connection of the respective vertically extending wall edges.

Description

The invention relates to a container comprising a wall provided with a profile in order to prevent said wall from bending outwards. The invention relates in particular to a container for transport and storage of liquids, preferably liquid chemicals.
Such a container is widely known. In practice the known container, which is generally made of polyethylene (PE), polypropylene (PP) or polyamide (PA), is often used for transport and storage of hazardous materials. The term hazardous materials as used herein is understood to mean materials which are legally designated as such in a particular country. The known container are usually subdivided in roughly two classes: durable containers having a wall thickness of about 8 mm, as well as containers to be used "once only" (up to five times, for example). It will be apparent that containers of the latter category must be made as cheap as possible, whereby first of all a saving on the cost of materials must be considered.
One drawback of the known container is the fact that it has become apparent in practice that the above saving on the cost of materials is hardly possible, if at all, since a container having a (considerably) smaller wall thickness than the usual 8 mm exhibits undesirable deformations in use. Said deformations are caused by a lateral pressure exerted by a chemical liquid which is present in the container, which causes ribs in the profile of the container wall to move apart.
The object of the invention is to obviate the drawbacks of the prior art, thus making it possible to provide thin-walled plastic containers having a sufficient wall strength, and in order to accomplish that objective, a container of the kind referred to in the introduction is characterized in that the profile is at least partially closed. Preferably, the profile is thereby formed by at least one, at least substantially U-shaped wall part extending inwards from the wall at the location of two opposed wall edges, seen in horizontal cross-sectional view of the wall, which wall part is closed in at least one place by connection of the respective vertically extending wall edges. This connection forms a "bridge", as it were, between ribs present in the profile, so that the aforesaid lateral deformations caused by the liquid pressure are prevented from occurring. This makes it possible to manufacture thin-walled containers which are suitable for use "once only" at a considerably lower cost price than the usual, durable containers.
In one preferred embodiment of a container according to the invention, said wall part is closed in at least two places, preferably in at least three places. Preferably, the wall part is entirely closed, at least substantially so. The advantage of this is that the container, depending on what is required in practice, possesses increased wall strength, which makes it possible to make the wall considerably thinner. Preferably, the wall has a thickness of 2 - 6 mm, in particular 4 - 5 mm.
In another preferred embodiment of a container according to the invention, the connection between the respective wall edges is made in one piece with the wall. It is preferred to manufacture the container according to the so-called "kiss-on/kiss-off" principle by means of rotational moulding.
In another preferred embodiment of a container according to the invention, said wall part continues over the upper side and/or the bottom side of the container.
In another preferred embodiment of a container according to the invention, several wall parts are arranged in evenly spaced-apart relationship over the circumference of the wall. The wall is thus uniformly strengthened over its entire circumference.
In another preferred embodiment of a container according to the invention, said container is made of a plastic, in particular PE, PP or PA. Preferably, a rotational moulding process is used thereby.
The invention furthermore relates to a method for manufacturing a container comprising a wall provided with a profile in order to prevent the wall from bending outwards, characterized in that, seen in horizontal cross-sectional view of the wall, said profile is formed by at least one, at least substantially U-shaped wall part extending inwards from the wall at the location of two opposed wall edges, which wall part is closed in at least one place by connecting the respective vertically extending wall edges.
The invention will now be explained with respect to figures illustrated in a drawing of a preferred embodiment of the invention, wherein:

Figure 1 is a schematic, perspective view of a container according to the invention;
Figure 2 is a schematic plan view of the container of Figure 1; and
Figure 3 is a schematic, horizontal cross-sectional view of Part of the container of Figure 1.

Figure 1 shows an at least substantially cubic (liquid) container 1, in particular for liquid chemicals. The container 1, which is provided with a filer cap 2 and a draw-off cock 3, is placed on a pallet 4 to facilitate transport and storage.
Container 1 is provided with a profile which is evenly distributed over the circumference of the wall 5. Seen in horizontal cross-sectional view of wall 5, said profile is made up of several at least substantially U-shaped wall parts 7, which each extend inwards from wall 5 at the location of two opposed wall edges 6 (Figures 2 and 3). In accordance with the invention, said wall parts 7 are closed in vertical direction over a particular distance by bridges 8, which form a connection between the respective wall edges 6. Wall parts 7 and bridges 8 jointly form O-shaped cylinders 9, as it were.
Bridges 8 prevent stiffening ribs 10 of the profile of the container 1 from moving out when container 1 is being filled with a chemical liquid, which would lead to undesirable deformation.
In Figures 2 and 3, those parts that correspond with parts which are shown in Figure 1 are indicated by the same numerals.

Claims

A container comprising a wall provided with a profile in order to prevent said wall from bending outwards, characterized in that said profile is at least partially closed.
A container according to claim 1, wherein said profile is formed by at least one, at least substantially U-shaped wall Part extending inwards from the wall at the location of two opposed wall edges, seen in horizontal cross-sectional view of the wall, which wall part is closed in at least one place by connection of the respective vertically extending wall edges.
A container according to claim 2, wherein said wall part is closed in at least two places, preferably in at least three places.
A container according to claim 2 or 3, wherein said wall part is entirely closed, at least substantially so.
A container according to claim 2, 3 or 4, wherein the connection between the respective wall edges is made in one piece with the wall.
A container according to any one of the preceding claims 2 - 5, wherein said wall part continues over the upper side and/or the bottom side of the container.
A container according to any one of the preceding claims 2 - 6, wherein several wall parts are arranged in evenly spaced-apart relationship over the circumference of the wall.
A container according to any one of the preceding claims 2 - 7, wherein said container is made of a plastic, in particular PE, PP or PA.
A container according to claim 8, wherein said container has been manufactured by means of a rotational moulding process.
A method for manufacturing a container comprising a wall provided with a profile in order to prevent the wall from bending outwards, characterized in that, seen in horizontal cross-sectional view of the wall, said profile is formed by at least one, at least substantially U-shaped wall part extending inwards from the wall at the location of two opposed wall edges, which wall part is closed in at least one place by connecting the respective vertically extending wall edges.