The invention relates to a lid for a container of the kind indicated in the preamble of claim 1.

Plastic lids of this kind are used for closing containers, preferably plastic containers, which on the outside below the rim have a wholly or partly encircling flange for securing i:he lid.

Such lids normally have to fit closely and it is demanded that it should be possible to remove the lid without recourse to tools. Furthermore the lid has to be designed in such a way that it may be put back in place in ord§r for the container to be reclosed. It must be possible to open and reclose the con¬ tainer a certain number of times until the container is empty, without reduction of the strength and tightness.

Several container lids are known by which the above mentioned qualities are aimed at, f. inst. from DK patents no. 145.194 and 154.549.

The object of the invention is to indicate a container, lid of the above mentioned kind in which the desired qualities with regard to tightness and reclosability are achieved in a new way without risk of undesired by-effects.

This object will be achieved by designing the container lid according to the invention as indicated in the characterizing part of claim 1. By dividing the flange of the lid into more than one encircling area the opening and the reclosing is made possible without stretching the flange of the lid in the area of the edge. The opening and closing is effected by a^movement in a vertical direction, i. e. in the axial direction of the container so that the edge of the flange will not be stretched resulting in a very great annular tension, as is often the

case in the conventional constructions. Especially in the case of reclosing, the special advantages of the invention are remarkable, as the stretching of the outer edge of the lid is avoided immediately before the flange is to engage with the locking rim of the container.

The container lid according to the invention is preferably designed as indicated in the characterizing part of claim 2. Hereby an embodiment is achieved which is easy to produce and in which the lid flange functions as a kind of double hinge. It is generally known to produce easily bendable areas by narrowing down the thickness of material in such a way that a weakened area is created, f. inst. if the lid is injection molded from polypropylene or similar plastic materials.

It is obvious for a person skilled in the art that the easily bendable ares or parts can be made or produced in other ways, f. inst. by reducing the stiffness of the material by perfora¬ tions or similar means, but they are preferably produced by reducing the thickness of the material.

By designing the container lid according to the invention as indicated in the characterizing part of claim 3, a solid and precise positioning of the flange in its locked state is acheived resulting in a strong and solid securing of the lid, which can only be removed by lifting the locking bead free of the container flange and then shifting the lower part of the encircling flange parts upwards.

By designing the container lid according to the invention as indicated in the characterizing parts of claim 4 or claim 5, an embodiment of the weakened areas is achieved which assists in making the flange parts move as desired and in such a way that the lower flange part substantially forms the same angle to the plane of the lid, both when the lid is removed and when it is on and during the intervening movement.

By designing the container according to the invention as indicated in the characterizing part of claim 6, a gripping edge is formed which simplifies the removal of the lid.

By designing the container lid according to the invention as indicated in the characterizing part of claim 7, it is ren¬ dered possible to remove the lid by a comparatively small movement of the encircling, downwards protruding flange of the lid and with a correspondingly small bending of the weakened areas. Besides, mounting and remounting of the lid on the con¬ tainer is possible without any substantial deformation of the lid, so that the desired complete tightness is achieved imme¬ diately.

If the container lid is designed as indicated in the characte¬ rizing part of claim 8, the outer part of the flange of the lid will rock a little outwards at the outer weakened area, i. e. approximately at the middle of the lid flange or the jacket, and this further assists in facilitating the removal of the lid. The. locking bead of the lid only has to be free of the outer edge of the container flange for the lid to be remo¬ ved freely.

If the container lid according to the invention is designed as indicated in the characterizing part of claim 9, i£ is achie¬ ved that one of the weakened areas is situated exactly where the moment is the greatest during the removal of the lid, whereby less force has to be applied for the removal of the lid than would be the case if the weakened area was placed further out on the flange of the lid.

If the container lid according to the invention is designed as indicated in the characterizing part of claim 10, the encirc¬ ling upper edge of the lid will also be moved a little upwards during the removal of the lid so that the necessary movement of the flange of the lid will be distributed to all the parts. Hereby the removal of the lid is facilitated and simplified.

The invention is explained further in relation to a preferred embodiment shown in the drawing, in which

fig. 1 shows the upper part of a container with a lid accor¬ ding to the invention, partly as a side view and partly as a sectional view,

fig. 2 is a radial part section through the edge of the con- tainer and the lid on a larger scale,

fig. 3 is a radial part section through the edge of the con¬ tainer and the lid according to a second embodiment of the invention, and

fig. 4 shows the same as fig. 3, but with the lid free of the container.

In fig. 1 a container lid 1 according to the invention is put on a plastic container 2 which has en encircling, annular flange 5, which is engaging the flange of the lid which in the embodiment shown comprises two encircling flange parts 8 and 9, the lower flange part having an internal encircling locking bead 10 which may be snapped under the lower edge of the con- tainer flange.

The invention is explained more closely in the following with reference to fig. 2 which shows a radial part section through the edge on a larger scale. Fig. 2 shows in a full line the container lid on the container 2 and in a dot-dash-dot line the container lid when the flange is free of the container.

The container 2 comprises a comparatively sharp sealing edge 3 at the mouth of the container, and an annular flange 5 below this which is cast integral with the container and which flange is terminated downwards by a locking edge 6. To impart a suitable stiffness to the flange 5, evenly spaced radial

ribs 14 are cast integral with the container.

A container lid 1 of elastically deformable plastic has an en¬ circling flange part which comprises an upper edge part 7 and in continuation hereof two flange parts, i. e. an upper flange part 8 and a lower flange part 9, connected by narrowed down parts or weakened lines 11, 12. The lid is injection molded as an integral unit.

The edge area 6 is provided with a downwards turned, axial guiding rib 4 which is contacting the outer surface of the container, and which together with the part of the container lid 1, which is contacting the inner surface of the container, forms the closure and seal between the lid and the container.

The upper narrowed down part 11 is formed from the inside, so that the upwards turned sealing edge area has an even, smooth surface, and the lower narrowed down part 12 is formed from the outside as shown in the drawing. The lower flange part 9 ends in a periferal terminal edge 13 which is rounded and, as shown, turned slightly outwards so that it forms a gripping edge which is easy to grip 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 placed inside the container, preferably 'has a rounded edge 15. Hereby the area 15 may be used during the removal of the lid, as f. inst. the thumb is placed against the area 15 and the rest of the fingers are gripping under the edge 13 of the lid. The edge of the lid is then lifted so that the locking bead 10 is freed from the flange edge 6 and the lid is slipped from the position, which is shown in a full line, to the position, which is shown in a dot-and-dash line. This parallel displacement of the flange of the lid results in that only the upper flange part 8 and the two weakened lines 11 and 12 are deformed. The lower flange part 9 is by and large not deformed, neither when opening the lid, nor when

closing it. Stretching of the edge area 13 during the closing proces is hereby avoided, and the annular tension built into the flange part 9 is preserved fully so that the locking bead 10 will engage the locking edge 6 without problems.

Both during opening and reclosing of the container lid the angle a between the lower flange part and the plane of the lid is maintained, while the part of the flange, which is consti¬ tuted by the upper flange part 8, rocks around the weakened line 11. The upper flange part 8, however, has no other pur¬ pose than to function as a kind of double hinge, as the tightening and securing of the lid is established by other parts of the container lid. In this way the tightening, rocking and securing of the lid has been distributed to diffe- rent parts of the edge of the lid. This makes it possible to maintain the qualities of the lid even after having opened and closed it repeatedly.

Figs. 3 and 4 show another enbodiment of the container lid according to the invention.

The flange of the lid is in this enmbodiment divided into three encircling areas. I. e. in one substantially radial area 8 and two areas 9 and 16 which are substantially axial in relation to the container 2. The three areas are hinged together and hinged to the edge part 7 of the lid proper 1 by means of intergral hinges or encircling weakened areas, 11', 17, 12, of which the weakened areas closest to the lid proper, i. e. 11' and 17, are formed on the surface of the flange of the lid which is turned inwards towards the container, and the outermost weakened area 12 is formed on the outwards turned surface of the flange of the lid.

Otherwise the same references have been applied as in the pre- vious figures.

Fig. 3 shows that the flange of the lid during the removal of

the container lid makes a much smaller movement than in the embodiment shown in fig. 2, as the movement is distributed among all three encircling parts. As soon as the bead 10 has been shifted to the upper side of the locking edge 5 the lid may be freely removed.

Fig. 4 shows the lid free of the container 2. The lid is mol¬ ded in this shape and therefore fig. 4 also shows the lid during its application. The lid is snapped on the container 2 by pressing the upper surface of the lid lightly, as the locking bead 10 without violent deformations or great increa¬ ses of the annular tension in the bead 10 is pushed down under the locking edge 6, thereby ensuring full tightness immediate¬ ly after the mounting of the lid.

It is apparent from figs. 3 and 4 that the narrowed down part 11' is placed where the moment in the flange of the lid will be the greatest when the lid is actuated for removal, i. e. as close to the reinforcement rib 4 as possible.

Furthermore, it is apparent from fig. 3 that no regular paral¬ lel displacement of the outer flange part 9 takes place in this embodiment, but that the flange part is rocked slightly outwards during the removal which helps to reduce the energy consumption required to lift the locking bead 10 free of the locking edge 6. This is achieved without on the Other hand making the lid too easily removable, f. inst. due to shock impacts or during transport.