Field of Search:
220/6R,72,74,42C,97E 292/256.6,256.61,256.63,256.65,256.67,256.69
Claims:
What we claimed is
1. In a liquid tight container having a lid retained over the top of the container by a locking ring, one of said lid and top having a channel-shaped profiled edge with a hook-shaped thickened portion on its outer flange and the other having a protruding portion extending into said channel-shaped profiled edge with a groove complementary to said thickened portion on its outer periphery and a resilient sealing member within said channel-shaped profiled edge, the improvement comprising:
2. The container of claim 1, in which the channel-shaped profiled edge is on the lid and the inner flange of said channel-shaped profiled edge is reinforced by a plurality of triangular ribs.
3. The container of claim 1, in which the complementary groove has an outside ridge engaged by a flange of the locking ring.
4. The container of claim 1, in which the leading edge of the protruding portion is of convex torroidal shape.
5. The container of claim 1, in which the lid has annular reinforcing ridges in its center panel substantially concentric with the channel-shaped profiled edge.
6. The container of claim 1, in which the lid is constructed from low density polyethylene.
Description:
The invention relates to a liquid sealed container, whose lid is retained by a locking ring, and is provided with a channel-shaped profiled edge in which a resilient sealing member is accommodated, which is engaged by the upper side of the container extending in the channel-shaped edge, the outward flange of the channel-shaped edge of the lid having a hook-shaped thickened portion which fits in a recessed portion of the rim of the container.
With structures of this type known in the art, the weight of the lid, and any additional containers stacked on top of the same, is wholly transfered to the top of the container through the resilient sealing member. Accordingly, said sealing member may be compressed to such an extent that it is not capable of forming an effective sealing means. The member is turned into a dead member.
It is the object of the invention to avoid said disadvantage by constructing the container sealed against liquids, described in the preamble, in such a way that the load transfer function and the sealing function are turned into two separate functions.
For this purpose, according to the invention, the inside flange of the channel-shaped edge of the lid extends within a recessed portion of the container rim which opens on to the interior of the container and rests upon the bottom of said recessed portion, on account of which the compression of the resilient sealing ring by the top of the container can be limited.
The inside flange of the liquid sealed container according to the invention, under all circumstances, may be passed into the aforesaid recessed portion of the rim of the container in a simple manner, whereby said flange, on account of the fact that it rests on the bottom of the recessed portion, is capable of wholly transfering the axial load on the lid to the wall of the container.
In this respect it is of importance that the axial load on the lid -- caused by a full container being placed on said lid, for instance -- is transfered to the inside flange, causing said flange to be pressed outwardly against the peripheral wall of the aforesaid recessed portion. To this end, the inside flange of the channel-shaped edge of the lid is preferably reinforced by a number of triangular ribs which extend within a second channel-shaped profile.
In order to have the locking ring with a relatively large surface engage part of the upper rim of the container, the recessed portion in the rim of the container designed for the hook-shaped thickened portion of the outside flange of the lid may at the lower side thereof be limited by a ridge which is engaged by a lower flange of the locking ring.
The upper part of the rim of the container extending between the aforesaid flanges of the lid is preferably of convex design.
In order to take up variations in pressure between the interior and exterior of the container, as well as to prevent the lid from being damaged if the container is dropped, for instance, the flexibility of the lid may be increased by providing it with annular ridges. With this it is moreover achieved that the lid is placed in the locking position more simply.
An alternative possibility of increasing the flexibility of the lid is the use of flexible material, such as polyethylene of low density.
The invention will now be described in more detail with reference to the Figures wherein a preferred embodiment of the invention is shown.
FIG. 1 shows an elevational view of a container according to the invention, while a sectional view is shown of the lid and the sealing edge of the container, however.
FIG. 2 shows a concentric sectional view through the edge of the lid.
FIG. 3 shows a sectional view of the closure of lid and container at an enlarged scale.
The container shown in the figures has a profiled upper rim 2 which mates with a profiled sealing edge 3 of the lid 4. The sealing edge 3 comprises an inside flange 6 and an outside flange 7, which flanges extend substantially parallel to one another and are spaced apart.
The inside flange 6 fits into a recessed portion 8 of the rim 2 of the container. Said recessed portion 8 of the rim opens on to the interior of the container, so as to afford an easy access to the inside flange 6, even if there should occur slight deviations in size due to variations in shrinking.
The inside flange 6 is reinforced by triangular ribs 9 which extend between said flange 6 and the bottom face of the edge 3 of the lid.
The outside flange 7 of the sealing edge 3, in the proximity of the free end thereof, is designed as a hook-shaped, thickened portion 11. Said thickened portion 11 fits in a recessed portion 12 in the rim 3 of the container 1.
A locking ring 13, preferably constructed from steel, surrounds the lid 4. Said ring serves to retain the lid in a secure manner. The recessed portion 12 is bounded at the underside thereof by a ridge 14. The lower flange of the snap ring 13 engages said ridge, so that there is a relatively large area of contact between said ring and the container.
Between the inside flange and the outside flange 6 and 7 respectively there is arranged a resilient sealing member 16 made of foam polyurethane, for instance. Said member 16 is fixed on the edge of the lid by glueing or spraying. The top part 17 of the rim 2 of the container engages said member, so that there is provided a guaranteed effective sealing means.
It is apparent that the inside flange 6 is capable of transfering axial loads on the lid 4 to the wall of the container 1 without loading the sealing member. An external axial load may be produced, for instance, by a filled container resting on the lid, the lower edge of said container falling within the edge 3 of the lid. Said load is transfered to the inside flange 6 through the ribs 9, said flange thus being pressed outwardly against the wall of the recessed portion 8.
The outside flange 7 may comprise a closed cylindrical wall or lugs which are spaced apart.
The ribs 9 might be replaced by a massive inner edge; the use of ribs which are spaced apart will increase the flexibility of the mouth, however. Said flexibility is required for taking up variations in pressure between the interior and exterior of the container, as well as additional loads if a container is dropped, for instance. Furthermore, lid and container, on being cooled, may shrink to an unequal extent, causing deviations in size to occur, which are compensated by the flexibility of the lid.
In FIG. 1 it is shown how the flexibility of the lid is increased by annular ridges 18. It is furthermore feasible to increase the flexibility by using flexible material, such as polyethylene of low density.