DE69004420T2 - CONTAINER LID. - Google Patents

Description

The invention relates to a container with a lid of the type specified in the preamble of claim 1.

Plastic lids of this type are used to close containers, preferably plastic containers, which have a fully or partially circumferential flange on the outside, below the rim, for fastening the lid.

Such lids must normally fit tightly and it is required that it should be possible to remove the lid without resorting to tools. In addition, the lid must be designed in such a way that it can be put back into position to thereby re-seal the container. It must be possible to open and re-seal the container a number of times until the container is empty without reducing its strength and tightness.

Some container lids are known with which the above-mentioned properties are sought, for example from DK-B-145 194 and 154 549.

The object of the invention is to provide a container with a lid of the type specified above, with which the desired qualities in terms of tightness and resealability are achieved in a new way without the risk of undesirable side effects.

This object is achieved by forming the container with a lid according to the invention as specified in the characterizing part of claim 1. By dividing the Lid flange in at least three circumferential areas, opening and reclosing is possible without stretching the lid flange in the edge area. Opening and closing is effected by a movement in the vertical direction, that is, in the axial direction of the container, so that the edge of the flange is not stretched, which leads to a very large hoop stress, as is often the case with conventional designs. In particular in the case of reclosing, the particular advantages of the invention are considerable, since stretching of the outer edge of the lid immediately before the flange engages the closing edge of the container is avoided.

The container with a lid according to the invention is easy to manufacture and the lid flange acts as a kind of multiple joint. It is well known to produce easily bendable areas by reducing the thickness of a material in such a way that a weakened area is created, e.g. if the lid is manufactured by an injection molding process from polypropylene or similar plastic materials.

It is obvious to a person skilled in the art that the easily bendable regions or parts can also be manufactured or produced in other ways, for example by reducing the stiffness of the material by means of perforations or the like, but they are preferably produced by reducing the material thickness.

By forming the container with a lid according to the invention, it is made possible to remove the lid by a comparatively small movement of the circumferential, downwardly projecting lid flange and with a correspondingly small bending of the weakened areas. In addition, the attachment and detachment of the lid to and from the container is possible without any significant deformation of the lid. possible, so that the desired complete tightness is achieved immediately.

By forming the container with a lid according to the invention as specified in the characterizing part of claim 2, an embodiment of the weakened areas is obtained which contribute to the desired movement of the flange parts, in such a way that the lower flange part forms substantially the same angle to the lid plane both when the lid is removed and when it is seated and during the movement therebetween.

When the container is designed with a lid as specified in the characterizing part of claim 3, the outer part of the lid flange projects slightly outwards at the outer weakened area, i.e. approximately at the middle of the lid flange or the panel, and this further contributes to facilitating the removal of the lid. The closure bead of the lid only has to be free from the outer edge of the container flange so that the lid can be freely removed.

If the container with lid is designed according to the invention as stated in the characterizing part of claim 4, it is achieved that one of the tapered areas is located exactly where the moment is greatest when removing the lid, and the upper peripheral edge of the lid is also moved slightly upwards when the lid is removed, so that the necessary movement of the lid flange is distributed over all parts. This makes removing the lid easier and simpler.

The invention is further explained with reference to the drawing in which

Fig. 1 shows the upper part of a known container with lid, partly in side view and partly in cross section,

Fig. 2 is a partial radial section through the edge of the known container and the lid on a larger scale,

Fig. 3 is a partial radial section through the edge of a container and a lid according to the invention, and

Fig. 4 shows the same as Fig. 3, but with the lid removed from the container.

In Fig. 1, a container lid 1 is placed on a plastic container 2, which has a circumferential, annular flange 5 that engages the lid flange, which in the embodiment shown comprises two circumferential flange parts 8 and 9, the lower flange part having an inner circumferential locking bead 10 that can be snapped under the lower edge of the container flange.

The function of the container with lid is described in more detail below with reference to Fig. 2, which shows a partial radial section through the edge on a larger scale. Fig. 2 shows in solid line the container lid on the container 2 and in dashed line the container lid with the flange exposed from the container.

The container 2 comprises a comparatively sharp sealing edge 3 at the opening of the container and an annular flange 5 below it, which is molded in one piece with the container and which ends at the bottom with a closing edge 6. In order to give the flange 5 a suitable rigidity, equally spaced radial ribs 14 are molded in one piece with the container.

A container lid 1 made of elastic, deformable plastic has a peripheral flange which comprises an upper edge part 7 and, in continuation thereof, two flange parts, i.e. an upper flange part 8 and a lower flange part 9, which are connected to one another by parts with reduced wall thickness or weakening lines 11, 12. The lid is manufactured as a one-piece unit by injection molding.

The edge region 6 is provided with a downwardly directed, axial guide rib 4 which contacts the outer surface of the container and which, together with the part of the container lid 1 which contacts the inner surface of the container, forms the closure and the seal between the lid and the container.

The upper weakened line 11 is formed from the inside so that the upwardly directed sealing edge region has a flat, smooth surface, and the lower weakened line 12 is formed from the outside as shown in the drawing. The lower flange portion 9 terminates in a peripheral end edge 13 which is rounded and, as shown, slightly bent outwards so that it forms a gripping edge which can be easily grasped with the fingers when the lid has to be removed.

The area between the edge part 7 and the part of the container lid which is arranged inside the container preferably has a rounded edge 15. This the area 15 can be used when removing the lid in such a way that, for example, the thumb is pressed against the area 15 and the remaining fingers grip under the edge 13 of the lid. The edge of the lid is then lifted so that the locking bead 10 is released from the flange edge 6 and the lid is moved from the position shown in solid line to the position shown in dashed lines. This parallel displacement of the lid flange has the result that only the upper flange part 8 and the two weakened lines 11 and 12 are deformed. The lower flange part 9 is largely not deformed, neither when the lid is opened nor when it is closed. Stretching of the edge area 13 during the closing process is thereby avoided and the ring tension built into the flange part 9 is fully maintained so that the locking bead 10 can easily grip under the closing edge 6.

Both during opening and during re-closing of the container lid, the angle α between the lower flange part and the plane of the lid is maintained, while the part of the flange formed by the upper flange part 8 pivots around the weakened line 11. The upper flange part 8, however, has no other purpose than to function as a kind of double joint, since the sealing and securing of the lid are achieved by other parts of the container lid. In this way, the sealing, pivoting and securing of the lid have been distributed over different parts of the lid edge. This allows the properties of the lid to be maintained even after it has been repeatedly opened and closed.

Figs. 3 and 4 show the container with a lid according to the invention.

The cover flange is divided into three circumferential annular regions; a first, substantially radially extending circumferential region 8, a second, substantially axially extending circumferential region 16 and a third, substantially axially extending circumferential region 9. The cover flange is connected to the cover edge to edge by a first circumferential weakened region 11' and the annular flange regions are connected to each other edge to edge by a second 17 and a third 12 weakened region, as shown in Figs. 3 and 4.

The lid flange in this embodiment is divided into three circumferential regions. That is, into a substantially radial region 8 and two regions 9 and 16, which are substantially axial with respect to the container 2. The three regions are hingedly connected to one another and to the edge part 7 of the actual lid 1 by means of integrated hinges or circumferential weakened regions 11', 17, 12, of which the weakened regions closest to the actual lid, that is, 11' and 17, are formed on the surface of the lid flange which faces inwards, towards the container, and the outermost weakened region 12 is formed on the outwards-facing surface of the lid flange.

The same reference symbols were used as in the previous figures.

Fig. 3 shows that the lid flange makes a much smaller movement during removal of the container lid than shown in Fig. 2, since the movement is distributed over all three circumferential parts. As soon as the bead 10 has been displaced to the top of the closing edge 6, the lid can be freely removed.

Fig. 4 shows the lid detached from the container 2. The lid is molded in this shape and Fig. 3 therefore also shows the lid during use. The lid is snapped onto the container 2 by gently pressing on the top of the lid, whereby the closing bead 10 is pushed downwards under the closing edge 6 without any strong deformations or major increase in the hoop stress in the bead 10, thus ensuring complete tightness immediately after the lid is fitted.

It can be seen from Fig. 3 and 4 that the weakened line 11' is located where the moment in the cover flange is greatest when the cover is operated for removal, that is, as close to the reinforcing rib 4 as possible.

Furthermore, it can be seen from Fig. 3 that no real parallel displacement of the outer flange part 9 takes place, but that the flange part is pivoted slightly outwards during removal, which helps to reduce the energy consumption required for lifting the locking bead 10 free from the closing edge 6. This is achieved without, on the other hand, making the lid too easy to remove, for example due to impacts or during transport.

Claims (4)

1. Container with a lid (1) made of elastically deformable plastic material, the opening of the container having a rim (3) provided with an outer container flange (5) pointing in the opposite direction to the container opening, the lid (1) having a peripheral lid flange (8, 9, 16) designed to engage around the outer container flange (5) of the container opening (2), the lid flange clamping the container flange under tension when the lid is mounted on the container, and the lid having the peripheral stiffening rib (4) arranged axially on the underside of the lid and mounted so as to clamp around the rim (3) of the container opening on the outside thereof, characterized by the combination that a) the container lid is divided into at least three circumferential annular regions (8, 9, 16) which comprise a first, circumferential region (8) extending essentially in the radial direction, a second,circumferential region (16) extending essentially in the axial direction, and a third,circumferential region (9) extending essentially in the axial direction, which are connected to the container lid edge to edge by a first,circumferential, weakened section (11') and to one another by a second (17) and third (12) circumferential, weakened section; b) the third peripheral region (9) has a peripheral, inwardly directed closing bead (10) which is arranged in the vicinity of the edge of the peripheral region which is opposite the weakened section (12) which connects the third peripheral region (9) to the second peripheral region, and c) the first weakened section (11') is provided directly on the outside of the circumferential stiffening rib (4). 2. Container with a lid according to claim 1, characterized in that the first peripheral weakened section (11') is formed into the inside of the cover flange. 3. Container with a lid according to claim 1 or 2, characterized in that the third circumferential weakened section (12) is formed into the outside of the lid flange. 4. Container with a lid according to claim 1, wherein the lid flange, when the lid (1) is mounted on the container (2), comprises a first, substantially radially extending, circumferential region (8) and a second and a third, substantially axially extending, circumferential region (9, 16), characterized in that the inwardly directed first and second weakened sections (11', 17) are arranged in the radially extending region and in the connecting section between the radially extending region and the axially extending regions.