DK3048060T3 - Container with sealing edge and gasket - Google Patents

Description

Description

Container with sealing edge and package

The invention relates to a container, in particular a bucket, comprising: a circumferential side wall on which in the area of an opening of the container a circumferential container edge is formed which protrudes past the side wall towards the outside and/or towards the inside and has an upper side with a width of at least 2 mm for applying an, in particular, peelable foil, as well as a circumferential skirt which has an engagement area for cooperation with a lid in order to close the container by means of the lid, wherein a plurality of webs (or supporting ribs) are formed between the side wall, a circumferential outer edge of the skirt, and an upper edge of the skirt. The invention also relates to a package comprising a container of this type and a lid for closing the container. DE 20 2011 100 541 Ul discloses a packaging container comprising a lid and a container for storing food which can preferably be filled in a hot state. The container has an upper container edge which protrudes to the outside past the side wall and can be used as sealing edge and merges into a skirt. The container edge has an upper side with a sufficient width (e.g. 3 mm) in order to weld a foil onto the upper side of the container edge to thereby ideally sealingly close or seal the opening of the container. The welded foil can be removed e.g. by a consumer in order to get access to the filling material, e.g. food filled into the container.

In addition to the foil, a lid formed as a clamping lid or snap-on lid can be fixed to the upper container edge of the container described in DE 20 2011 100 541 Ul. In one example, the lid comprises an outer area over which the lid is clamped on the upper skirt area of the container. The upper part of the side wall of the container and its neighbouring skirt area in the upper part of the container are stabilized via webs which extend up to the upper container edge forming the sealing edge. DE 34 47 558 A1 describes a combined container, in particular of a transparent plastic material for food, which consists of a lower part, in particular a cup, and a lid. The lid can be sealingly closed by a diffusion foil. In the area of the cup opening, the wall of the cup merges into a stacking edge which extends horizontally slightly to the outside from the cup shell and at an upper edge it merges into a horizontal sealing edge which receives the diffusion foil, both having the same thickness. On its inner side, the snap cover may have a circumferential groove into which a collar that extends at an angle in an outward and downward direction away from the sealing edge can engage in a snapping manner. US 5 730 309 A describes a container with a lid, wherein a tight closure is achieved by locking with a plurality of annular flanges.

It is the object of the invention to further develop a container and a package of the above-mentioned type in such a manner that the sealing effect of a foil to be welded onto the container edge is increased.

This object is achieved in accordance with a first aspect by a container of the above-mentioned type, in which the container edge used as sealing edge and the skirt are arranged at a distance from one another along the side wall of the container and the sealing edge does not contact the radial webs or ribs arranged above or below it.

In accordance with the invention it was found that there are problems with the application of the foil with the container described in DE 20 2011 100 541 Ul in which the container edge forming the sealing edge also forms the upper side of the skirt which is normally reinforced by radial ribs or webs between the side wall and the skirt e.g. in case of packaging buckets. It has turned out that in the production of the container in an injection moulding method, the upper edge of the skirt has a sink mark in a respective section in the circumferential direction where a web is formed, i.e. the otherwise substantially flat upper side of the upper edge of the skirt has a depression in the area of a respective web, which depression extends from the circumferential side wall towards the outer edge of the skirt. If a foil were to be applied to the upper edge of the skirt e.g. by ultrasound welding, the connection in the area of the depression might possibly not be complete such that the foil might not completely sealingly close the opening and the sealing effect might be impaired.

Sink marks of this type thus prevent ideally sealing application of a sealing foil onto the container edge. In accordance with the invention, the sealing function and the reinforcing skirt function are therefore separated in that the container edge that can be used as sealing edge is formed to be at a distance from the skirt and thus is not in contact with webs or ribs. In this manner, the sink marks or unevenness that are possibly generated during the production of the skirt cannot have any effect on the upper side of the container edge used as sealing edge and no sink marks are generated in the area of the container edge in the production of the container in an injection moulding method. The production of such a container in which the container edge and the skirt are arranged at a distance from one another in an injection moulding method typically requires the use of sliding moulds for demoulding. The container edge of a container of this type has an almost completely smooth surface such that a preferably peelable foil can be welded thereon in a sealing manner. A peelable foil means a sealing foil which can be removed from or peeled off the sealing edge without thereby tearing the foil.

The upper side of the container edge extends starting from the circumferential side wall in a substantially horizontal direction (i.e. parallel to the bottom of the container) in order to enable application of the, in particular, peelable foil. If necessary, the upper side of the container edge may be tilted by a small angle (typically less than approximately 10°) with respect to the horizontal direction. The upper side of the container edge should ideally be planar but may also have a slight curvature, if necessary. The container edge can extend, starting from the side wall, to the outside and/or inside, i.e. into the area of the opening. The container edge is typically formed with a substantially constant wall thickness, i.e. it has a lower side which extends substantially parallel to the upper side.

If necessary, a typically circumferential elevation (having a size of one or a few tenths of a millimetre) can be formed on the upper side of the container edge, the free end of which generally tapers and which forms an energy director for ultrasound welding for connecting the foil to the container edge. The ultrasound energy is coupled into the tip of such an energy director, whereby the director heats from the tip and becomes soft or is liquefied. The foil applied to the upper side of the container edge is glued to the container edge by the soft or liquefied plastic material of the director. During glueing the circumferential elevation disappears such that after ultrasound welding the container edge is planar on its upper side or, if necessary, has a (desired) slight curvature.

The container edge generally has on its outer and/or inner edge no section that differs from the substantially horizontal orientation, i.e. extends from the upper side of the container edge to the top or to the bottom. Such a section as provided e.g. in DE 34 47 558 A1 on the outer edge of the container edge is not required in the present container since the lid is mounted to the container in the engagement area of the skirt. This type of mounting has turned out to be advantageous since with mounting the lid to the container edge (if necessary without skirt arranged below) there might be the problem that the lid becomes detached from the container during transport of a plurality of stacked packages on a common pallet when other packages exert a force from below against the lid. When the lid is mounted to the skirt, such inadvertent release of the lid can be prevented, in particular when an outer edge of the skirt located below the engagement area extends further to the outside than the outer edge of the lid disposed onto the container.

The skirt formed on the container typically comprises an upper edge which is connected to the side wall and extends from the side wall in a radial outward direction and which is followed by a circumferential outer edge which extends in a downward, i.e. vertical direction. The skirt, or to be more precise, a lower rim on the outer edge of the skirt, can be used to support the container on a corresponding insert during filling in a filling system. The webs arranged in a distributed manner along the side wall in the circumferential direction locally connect the outer edge of the skirt to the circumferential side wall and the upper edge of the skirt such that the overall skirt is stabilized.

In accordance with the present invention, the term "circumferential" does not necessarily mean complete circulation (around 360°) in the circumferential direction. However, the container edge is typically completely circumferential such that the foil completely seals the opening.

The upper side of the container edge has a width of at least 2mm, preferably at least 3mm, in particular at least 4mm. In this way, it is ensured that a, in particular, peelable foil can be welded onto the upper side of the container edge with a sufficient degree of precision.

The container edge or the overall container can have a wall thickness of less than e.g. 1.0mm. A minimum wall thickness of the container or of the container edge reduces the material required and therefore the production costs of the container. It is clear that the wall thickness of the container edge must not be selected too small in order to ensure that the container edge is sufficiently stable.

In one embodiment, an upper edge of the skirt has a distance of at least 0.5mm and at most 15mm from the container edge. It has turned out to be favourable to arrange the upper edge of the skirt at a sufficient distance from the container edge that projects past the side wall in order to enable engagement or cooperation between the lid and the engagement area of the skirt. The distance between the container edge and the upper edge of the skirt should otherwise not be too large to prevent the outer edge of the lid from having to be excessively prolonged in a downward direction in order to be able to cooperate with the engagement area of the circumferential skirt.

In one further embodiment, a clamping profile is formed in the engagement area of the skirt for cooperation with a lid for the container. The clamping profile may e.g. be a round circumferential projection which cooperates with a further projection, which is formed on the inner side of the lid edge, for forming a clamping connection in the engagement area. The further projection or the clamping connection of the lid can engage below or behind the clamping profile of the skirt for producing a clamping or locking connection in the engagement area.

In one further embodiment, the container is produced from plastic material, in particular from polyolefins, e.g. from polyethylene or polypropylene. Containers of polyolefins, in particular of polyethylene or polypropylene are typically inexpensive to produce. Moreover, such containers have advantageous properties such as e.g. a high resistance due to high toughness values and elongation at break values. The container may generally also be produced from other plastic materials (in particular from thermoplasts, optionally also from thermosets).

In one embodiment, the container is produced in an injection moulding process. For demoulding the above-described container, in which the container edge and the skirt are arranged at a distance from one another, in an injection moulding process, it is typically required to use a sliding mould. After filling, a sealing foil can be applied to the upper side of the circumferential container edge of the container in order to close the opening in a sealing manner.

According to a further aspect, this object is achieved by a package comprising a container according to the invention and a lid that cooperates with the circumferential engagement area of the skirt. Mounting the lid in the engagement area of the skirt provides particularly secure fastening of the lid to the container e.g. via a clamping or locking connection. In particular, the lid can have a circumferential edge with an e.g. n-shaped profile, the outer leg of which continues in a downward direction until it can cooperate with the skirt in the engagement area of the skirt.

In one embodiment, the lid has a further clamping profile for cooperation with the clamping profile in the engagement area of the skirt. In the engagement area, the further clamping profile can be brought into engagement with the clamping profile of the skirt in order to lock the lid on the container and close it. The further clamping profile may e.g. be an, in particular, circumferential projection which engages below or behind the clamping profile on the skirt. It is clear that the cooperation between the lid and the engagement area of the container by a snap connection or locking connection can also be realized in a different manner than described herein.

Further advantages of the invention can be extracted from the description and the drawing. The features mentioned above and below can be used in accordance with the invention either individually or collectively in arbitrary combination. The embodiments shown and described are not to be taken as exhaustive enumeration but rather have exemplary character for describing the invention.

The invention is illustrated in the drawing and is described in more detail with reference to embodiments. In the drawing:

Figs, la-lc show a sectional view (Fig. la) of an embodiment of the container, and a detail of the container (Figs, lb, c) with a container edge and a skirt disposed at a distance therefrom in a sectional view and a perspective view, and

Figs. 2a-2d show several views of a package which comprises the container according to Figs, la-c and a lid which closes the container in the area of an opening.

The container 1 (bucket) illustrated in Figs, la-c comprises a bottom 2 and a circumferential side wall 3. A container edge 5 is formed on the upper side of the side wall 3 in the area of a round opening 4 for supplying a filling material, e.g. in the form of food, into the container 1, the container edge 5 radially protruding to the outside past the circumferential side wall 3. The protruding container edge 5 has an upper side 5a that extends in a horizontal direction (i.e. parallel to the bottom 2) of a width b of more than 2mm, in the illustrated example of approximately 3mm.

Such a width b is sufficient in order to use the container edge 5 as sealing edge, i.e. in order to apply an, in particular, peelable sealing foil (not illustrated) onto the upper side of the container edge 5, which covers the entire opening 4 in order to seal the filling material contained in the container 5. The circumferential container edge 5 has a wall thickness d of approximately 1.0 mm in the illustrated example. A circumferential elevation (not shown) may optionally be formed on the upper side 5a of the circumferential container edge 5, which forms an energy director for ultrasound welding.

The container 1 illustrated in Figs, la-c also comprises a circumferential skirt 6 which is formed on the circumferential side wall 3 at a distance from the container edge 5. The circumferential skirt 6 has an upper edge 7 which extends from the side wall 3 in a radial direction to the outside.

An engagement area 7a is formed on the upper edge 7 of the skirt 6 for cooperation with a lid.

The upper edge 7 of the skirt 6 merges on its side facing away from the side wall 3 into a circumferential outer edge 8 of the skirt 6 which extends in a downward direction. The outer edge 8 of the skirt 6 extends substantially parallel to the longitudinal axis of the container 1 extending in a vertical direction and forms with a section of the side wall 3 next to the outer edge 8 a double edge of the container 1. In the area in which the upper edge 7 of the skirt 6 is connected to the side wall 3 of the container 1, the skirt 6 has a distance A of approximately 5mm from the lower side of the container edge 5. The distance A between the upper edge 7 of the skirt 6 and the lower side of the container edge 5 is typically between approximately 0.5mm and approximately 15mm.

In the example illustrated in Figs, la-c, the upper edge 7 of the skirt 6, which comprises the engagement area 7a, has a circumferential projection which forms a clamping profile 9. The clamping profile 9 limits the engagement area 7a that cooperates with a lid 10 of a package 11, which is illustrated in Figs. 2a-d and is described in more detail below.

Fig. 2a shows the package 11 in a side view, Fig. 2b in a sectional view along the line of intersection A-A of Fig. 2a. Fig. 2c shows a detail of the sectional view of Fig. 2b and Fig. 2d shows a perspective view of the package 11. As is illustrated in Fig. 2c, the lid 10 has a circumferential edge 12 with a substantially n-shaped profile along the line of intersection A-A, the outer leg 13 of which continues in a downward direction until it projects into the area of the upper edge 7 of the skirt 6.

The outer leg 13 of the circumferential edge 12 of the lid 10 has on its inner side facing the container 2 a further clamping profile 14 which engages behind or below the clamping profile 9 formed on the upper edge 7 of the skirt 6 in the engagement area 7a. The engagement area 7a on the upper edge 7 of the skirt 6 forms a circumferential groove which extends inwardly in a radial direction and into which the further clamping profile 14 of the lid 10 engages.

As is illustrated in Fig. 2d, the lid 10 has a planar inner area 15 (lid panel) which is surrounded by the circumferential edge 12. As is illustrated in Fig. 2c, the inner area 15 of the lid 10 extends slightly above the container edge 5 in order to prevent the lid 10 from exerting a force from above against the sealing foil in the area of the opening 4.

As is illustrated both in Fig. lc and in Fig. 2c, a plurality of webs 16 are formed between the upper edge 7 of the skirt 6, the circumferential outer edge 8 of the skirt 6 and a section of the circumferential side wall 3 of the container 1 next to the circumferential outer edge 8 of the skirt 6, which are typically arranged in the circumferential direction substantially in regular intervals and are used to stabilize the skirt 6. The lower edges of the webs 16 can be used for abutment of a further container edge of a container arranged further down when stacking several containers 1 on top of one another.

As is illustrated in Fig. 2d, the container 1 comprises an opening flap 17 in the area of the skirt 6. Connections for a handle of the container 1, which are typically mounted to the outer edge 8 of the skirt, are not illustrated for reasons of clarity.

In the illustrated example, the container 1 consists of plastic material, in particular of polyolefins, e.g. of polyethylene or polypropylene. The container 1 is produced in one piece in an injection moulding process in the illustrated example. It is clear that the container 1 or the package 11 may also be formed in a different manner than shown in Figs, la-c and Figs. 2a-d. For example, the container 1 may have an e.g. oval or rectangular basic shape. The lid 10 may also have a correspondingly adjusted basic shape.

In the illustrated example, the outer edge 8 of the skirt 6 extends in a radial direction further to the outside than the outer edge of the lid 10 in order to prevent inadvertent lifting of the lid 10 from its lower side. The height of the skirt 6, to be more precise of the circumferential outer edge 8, may if necessary vary in the circumferential direction of the container 1, i.e. the outer edge 8 may have longer and shorter sections in the peripheral direction. It is clear that the type of mounting of the lid 10 to the skirt 6 by means of the clamping profiles 9, 14 in the engagement area 7a is merely exemplary and a snap connection or locking connection between the lid 10 and the skirt 6 can also be realized in a different manner than described herein.

Claims (10)

A container (1), comprising: a circumferential side wall (3) on which a circumferential container edge (5) protruding outward and / or inwardly over the side wall is formed in the region of an opening (4) of the container (1) (3), and a circumferential skirt (6) having an engagement region (7a) for interacting with a cover (10), between the side wall (3), a circumferential outer edge (8) of the skirt (6) and an upper edge (7) of the skirt (6) is formed a plurality of ribs (16), the container edge (5) and the skirt (6) being spaced apart along the side wall (3) of the container (1), characterized by the container edge (5) for use as a sealing edge has an upper side (5a) having a width (b) of at least 2 mm for applying a particularly peelable foil. Container according to claim 1, wherein the upper side (5a) of the container edge (5) extends the tilt relative to the horizontal direction, i.e. parallel to the bottom of the container (1), at an angle of less than 10 °. Container according to claim 1 or 2, in which an elevation is formed on the upper side (5a) of the container edge (5) which extends tapered towards its free end. Container according to one of the preceding claims, in which an upper edge (7) of the skirt (6) has a distance of at least 0.5 mm and not more than 15 mm from the container edge (5). Container according to one of the preceding claims, in which a clamping profile (9) is provided at the engagement area (7a) of the skirt (9) for cooperation with a cover (10) for the container (1). Container according to one of the preceding claims, which is made of plastic, especially of polyolefins. Container according to one of the preceding claims, which is made by an injection molding process. A gasket (11), comprising: a container (1) according to one of the preceding claims and a cover (10) cooperating with the circumferential engagement region (7a) of the skirt (6). The gasket according to claim 8, wherein the cover (10) has a flat inner region (15) extending a short distance above the container edge (5). The gasket of claim 8 or 9, wherein the cover (10) has an additional clamping profile (14) for interacting with the clamping profile (9) at the engagement area (7a) of the skirt (6).