WO2003099675A1

WO2003099675A1 - Container assembly

Info

Publication number: WO2003099675A1
Application number: PCT/NL2003/000405
Authority: WO
Inventors: Cornelius Maria Johannes Govers
Original assignee: Technoplast B. V.
Priority date: 2002-05-29
Filing date: 2003-05-28
Publication date: 2003-12-04
Also published as: NL1020707A1; NL1020707C2; EP1507715A1; AU2003273173A1

Abstract

Container assembly consisting of a tray-shaped bottom part (3) and a tray-shaped lid (2). The closure effective between them consists of a U-shaped part (10, 12) that is fixed to the lid and a straight end edge that is fixed to the bottom part. The straight end edge is inserted in the U-shaped part to produce closure. The U-shaped part and/or straight end edge are locally provided with elevations (22, 23) to provide a continuous connection between the interior and the exterior of the assembly, the dimensions of the connection being accurately defined.

Description

Container assembly

The present invention relates to a container assembly comprising a tray-shaped container part and a lid part, the free peripheral edges of the container part and the lid part being provided with interacting means for sealing lid part and container part on one another, which sealing means comprise a U-shaped end part arranged at the edge of the lid part or container part and a straight end part arranged at the edge of the container part or the lid part, the straight end part being provided with a thickening that is accommodated clamped on either side between the arms of said U-shaped end part. A container assembly of this type is disclosed in GB 725 882. This publication discloses a container for food where the lid sealingly engages on the tray-shaped bottom part.

Apart from for containing food, the containers are used for cultivating crops. For this application stringent requirements are imposed on the closure under certain conditions. One example of this is use of such containers in tissue culture, such as breeding and/or propagation of crops. These are handled in various stages by various persons treating them. In this context it is extremely important that no bacteria or moulds are able to enter the container during such a treatment. It is likewise important that such moulds/bacteria and/or other microoganisms, such as mite, are not able to penetrate into the container assembly during the cultivation phase. In the prior art it is proposed to solve this problem by making an opening in the lid and to shut off this lid with a filter to counteract the ingress of bacteria and the like.

Although such a construction is effective, the costs of producing a lid in this way are particularly high. Moreover, it has been found that such filters are clogged by water vapour that forms. This problem can be avoided by choosing larger pores for the filter, but it can then no longer be guaranteed that an effective barrier against undesirable particles is provided.

US Patent 3 339 786 discloses a container assembly with lid part and container part. The lid clamps by means of a peripheral rim on a raised edge of the container part. Sealing takes place in that the internal diameter of the peripheral rim is somewhat smaller than the external diameter of the raised edge of the container part. In practice, however, it has been found that with clamping from one side in this way an accurate and correct clamping fit cannot be assured under all circumstances, so that fitting ribs which make venting possible does not guarantee that no larger openings are produced between lid part and container part.

The aim of the present invention is to provide a container assembly with which it is possible in as inexpensive a manner as possible to provide a connection between the interior of the container assembly and the exterior of the container assembly where, on the one hand, clogging by water droplets is prevented and, on the other hand, it is guaranteed that undesirable bacteria and the like are not able to enter.

This aim is achieved with a container assembly as described above in that there is a number of elevations arranged sozne distance apart around the periphery on the arms of the U-shaped end part and/or the straight end part, in order to create a continuous slit bordering said elevations and extending from the interior to the exterior of said container.

According to the present invention a connection between the interior of the container assembly and the exterior is provided along an appreciable part of the periphery such as one side and more particularly round the entire periphery. With the aid of modern moulding techniques for plastic, such as injection moulding techniques, it is possible to form the elevations with an accurately defined size and thus accurately to determine the adjoining slit. According to an advantageous embodiment of the invention, the height of the elevations is 0.01 - 0.1 mm and more particularly approximately 0.05 mm. It has been found that with such a size, partly because of the location of the slit, no problems arise with penetrating bacteria, mites and the like. On the other hand, surprisingly, it has been observed that such a slit does not become clogged as a result of the effect of condensing water. A further guarantee that a liquid seal cannot be obtained by capillary action in the slit according to the invention can be achieved in that a flanged part that can be provided with a drip rib is arranged between the U-shaped part and the remainder of the lid part or bottom part.

As a result of the present invention "breathing" of the contents of the container assembly is possible and excess condensation can be prevented from arising on the inside of the lid. As a result of such excessive condensation of water and nutrients absorbed therein, the medium dries out and an irregular distribution of nutrients absorbed therein is produced and accordingly leads to irregular growth of the crop concerned.

Preferably, the container assembly according to the invention is used for tissue culture, such as the breeding and propagation of crops and in such a case a nutrient medium will be present. It must be understood that the container assembly according to the present invention has many other applications.

For simple removal of products present in the bottom part and to ensure an adequate height, it is proposed according to an advantageous embodiment of the invention to incorporate part of the height of the container in the lid, that is to say to construct said lid in the form of a tray.

More particularly, the height of the lid part comprises at least approximately 1/3 of the height of the tray-shaped bottom part. As a result of a relatively high lid part and the splaying of both the lid part and the bottom part towards the free end, the relationship between the available base surface and the largest dimension of the container assembly becomes more favourable, that is to say the required total surface area for a specific base surface area decreases. Further optimum utilization of the space in, for example, the climate-controlled treatment cabinets in which such container assemblies are placed can be obtained by making the container assembly of square or rectangular construction.

Greater flexibility of the closure can be obtained if the U-shaped part is not integrated in the side wall of, for example, the lid part but is joined thereto via a flanged part. As a result of such a flexible join any tolerances which, for example, arise during the production of the container assembly by injection moulding can easily be taken up and do not lead to undesirable stresses. By means of the flanged part it is furthermore ensured that any water of condensation that runs downwards along the lid can never enter the slit-shaped gap between the lid and the bottom part and can thus completely seal lid and bottom part via capillary means.

According to a further advantageous embodiment of the invention the free edge of the U-shaped part is bent outwards to some extent. By this means a centring effect of the opposite free edge is provided. The free edge of the U-shaped part can optionally be extended to provide further centring.

By choosing an appreciable height for the outside edge, when placed on a substrate (worktop), the inside of the lid is not able to touch said substrate, as a result of which contamination is prevented.

According to an advantageous embodiment of the invention, clamping of the lid part on the thickening takes place at positions on the thickening that are located diametrically opposite one another. Preferably, the thickening is made close to the end of the edge of the container part. By means of injection moulding techniques it is possible accurately to size both the dimensions of the thickening and of the body that joins the arms of the U-shaped end part, so that an accurate clamping fit between arms and thickening can be obtained. The invention will be explained in more detail below with reference to an illustrative embodiment shown in the drawing. In the drawing:

Fig. 1 shows, diagrammatically, a perspective view of the container assembly according to the invention;

Fig. 2 shows a cross-section according to Fig. 1, according to the section H-H; and Fig. 3 shows the cross-section according to Fig. 1, according to the section IH-iπ.

In Fig. 1 the container assembly according to the invention is indicated in its entirety by 1. This consists of a lid part 2 and a bottom part 3.

It can be seen from Fig. 1 that the container assembly is of essentially rectangular construction. Consequently, a number of such containers can be placed in contact with one another in an optimum manner and the storage space concerned can be put to optimum use. Further details of the container assembly according to the invention can be seen from Figs 2 and 3.

It can be seen from these figures that the lid part 2 comprises a top part 6 and an all- round side wall 7. This is of raised construction so that some of the volume of the container assembly is in the lid part.

Top part 6 is of somewhat recessed construction.

Arms 10 and 12 are provided in specific locations with elevations 22 and 23, respectively. In the example shown, the elevations 22 and 23 are opposite one another, but it is readily possible for these to be made offset (in the longitudinal direction of the relevant side). These elevations can be made on one side but also on several sides or can even extend completely around the periphery.

Alongside each of the elevations a slit is delimited that can be seen in Fig. 3. This slit is indicated by 25. By this means a possibility for ventilation is produced between the interior of the container assembly and the environment. Clamping action takes place in the regions between the slits. The length of the body

11 that joins the arms 10 and 12 can be accurately determined when injection moulding. The same applies in respect of the width of the thickening 18. Consequently, the space for ventilation between the arms 10 and 12 at the thickening 18 can be accurately guaranteed under all circumstances. This is even further improved if the peripheral rim of the lid part is separate from the side wall 7 as in the embodiment shown.

The flanged part 20 is provided with a drip rib 21. This prevents any moisture that, despite the improved ventilation of the container assembly according to the invention, may condense on the lid part from reaching the slit described above and being able to clog this slit as a result of capillary action. By means of the drip rib 21 such moisture will collect close to the free end thereof and possibly be guided, close to the periphery, to the bottom of the tray-shaped bottom part 3. The height of the elevations described above is such that a continuous slit approximately 0.05 mm in size is produced immediately alongside the elevations. As a result, undesirable elements, such as mites, are not able to enter but there is nevertheless adequate ventilation of the interior of the container assembly.

The container assembly described above can be made from any material known in the state of the art, such as polypropene. If this assembly is used for cultivating crops it is preferable to make the various parts transparent.

After placing the product concerned in the bottom part according to the invention, the lid is fitted on the end edge 17. This is then pushed downwards, after which engagement is ensured by the inward springing edges 10 and 12. Although the invention has been described above with reference to a preferred embodiment, it must be understood that numerous modifications can be made thereto without going beyond the scope of the present application. For instance, it is possible to provide the ridge and thickening with a wide variety of shapes and to make this at any location. These and further modifications will be immediately apparent to those skilled in the art after reading the above description.

Claims

1. Container assembly (1) comprising a tray-shaped container part (3) and a lid part (2), the free peripheral edges (12, 17) of the container part and the lid part being provided with interacting means for sealing lid part and container part on one another, which sealing means comprise a U-shaped end part (8) arranged at the edge of the lid part or container part and a straight end part (17) arranged at the edge of the container part or the lid part, the straight end part being provided with a thickening (18) that is accommodated clamped on either side between the arms of said U-shaped end part, characterised in that there is a number of elevations (22, 23) arranged some distance apart around the periphery on the arms of the U-shaped end part and/or the straight end part, in order to create a continuous slit (25) bordering said elevations and extending from the interior to the exterior of said container.

2. Container assembly according to Claim 1, wherein said elevations are arranged on the inside of the arms of the U-shaped end part.

3. Container assembly according to one of the preceding claims, wherein said elevations have a height of between 0.01 - 0.1 mm.

4. Container assembly according to Claim 3, wherein said elevations are approximately 0.05 mm high.

5. Container assembly according to one of the preceding claims, wherein said lid part is of tray-shaped construction with a height that is at least 1/3 of the height of the tray-shaped container part.

6. Container assembly according to one of the preceding claims, wherein said U-shaped end part adjoins said flanged part, which is provided with a drip rib (21).

7. Container assembly according to one of the preceding claims, wherein the straight end part is provided with said thickening (18) at the free end thereof.

8. Container assembly according to one of the preceding claims, wherein said thickening (18) is accommodated between the arms of said U-shaped end part such that it is clamped on diametrically opposite sides.

9. Container assembly for tissue culture of crops, comprising a container part designed to accommodate said tissue culture, as well as a lid part, characterised in that said container assembly comprises a container assembly according to one of the preceding claims.