DE29701943U1 - cover - Google Patents

Description

GRÜNECKER, Sc"S£HWANHÄUSSER
·«

LAW FIRM

LAW FIRM MAXIMILIANSTRASSE 58 D-80S38 MUNICH GERMANY Applicant:

WMF WUERTTEMBERGISCHE METALLWARENFABRIK AKTIENGESELLSCHAFT P.O. BOX 14 01
73309 GEISLINGEN/STEIGE LAWYERS

DR. HERMANN SCHWANHÄUSSER
DR, HELMUT EICHMANN
GERHARD BARTH
DR, ULRICH BLUMENRÖDER, LLM,
CHRISTA NIKLAS-FALTER

PATENT ATTORNEYS

EUROPEAN PATENT ATTORNEYS

AUGUST GRÜNEECKER

DR. HERMANN KINKELDEY

DR. WILFRIED STOCKMAIR, AE. E.

DR. KLAUS SCHUMANN

PETER H, JACOB

DR. GUNTER BEZOLD

WOLFHARD MEISTER

HANS HILGERS

DR. HENNING MEYER-PLATH

ANNE EHNOLD

THOMAS SCHUSTER

DR. WALTER LANGHOFF

DR. KLARA GOLDBACH

MARTIN AUFENANGER

GOTTFRIED KUTZSCH

DR. HEIKE VOGELSANG-WENKE

REINHARD KNAUER

DIETMAR KUHL

DR. FRANZ-JOSEF ZIMMER

BETTINA K, REICHELT

YOUR REF.

OUR REF.

G 3612-01104/Dr

DATE

04.02.97

Lid

TEL 089/21 23 SO · FAX 089 / 22 02 87 ■ TELEX 529 380 MONA D · EMAIL 100702.215S@COMPUSERVE.COM ■ DEUTSCHE BANK MUNICH, NO. 17 51734, BLZ 700 700 10

Lid

The innovation relates to a lid of the type described in the preamble of claim 1.

Such a lid is known, for example, from DE-GM 78 09 244 or DE-GM 79 19 123. The known lids are used to close cup-like plastic containers that are used to package food. The known lids have an outer edge that extends axially from the lid base and is provided with a bead near its free end that extends over the entire inner circumference of the outer edge at a predetermined distance from the free end. The known lids also have an inner edge at a predetermined radial distance from the bead, with the help of which the lids can also be stacked. The positive locking connecting devices in the form of beads, however, require a special shape of the lid edge and greater stability. The edge of the container that can be closed with the known lids must have a radially outward-facing area and an axially extending outer area that can be easily gripped by the bead. In addition, the edge of the lid must be relatively rigid so that when the bead is pressed onto the edge of the lid, for example when the container is upside down, it does not push the edge of the lid away so that the lid falls off.

DE-GM 78 25 655 also describes a lid that can be pressed into a container and is used specifically for disposal containers for medical waste. The lid essentially has the shape of a hollow, flat disk, the circumference of which is provided with circumferential beads that act as sealing lips. The lid is pressed into the interior of the container and held there by friction.

For effective sealing, precise dimensional adjustment is required.

Many foods, such as yoghurt, buttermilk, desserts, cream, etc., are currently offered in thin disposable plastic cups of various sizes and shapes, which are sealed with a metal foil. The metal foil is welded onto the radially protruding, essentially ring-shaped edge of the container. If the metal foil is lifted or removed to open it, the container can no longer be sealed. However, often not all of the food is consumed, so that it either has to be poured into a sealable container or a certain impairment of taste has to be accepted.

The innovation is therefore based on the task of creating a lid that is suitable for closing containers with a radially protruding edge, in particular disposable plastic cups.

The object is achieved by the cover specified in claim 1.

The axially extending clamping rib presses the edge of the container locally, so that the lid can be held firmly but releasably on the edge by local deformation and any springback forces activated by this, as well as by friction. The protruding rib also compensates for any diameter tolerances that are unavoidable in mass-produced items such as disposable plastic cups for milk products. With larger diameters, the edge is pressed in more strongly by the rib, and with small dimensional tolerances, the edge is pressed in less strongly by the rib or is only held in place by friction. The lid can be sold either separately or together with a (filled) plastic cup.

A particularly good clamping fit is achieved if three evenly distributed ribs are provided according to claim 2, so that the cover is centered at the same time.

With the cross-sectional shape of the ribs described in claim 3, the lid can be easily pressed on and does not get caught when removed.

Advantageously, the free end of the rib is bevelled or rounded according to claim 4, so that pressing the lid onto the edge is made even easier.

The design according to claim 5 ensures that the edge of the container always rests against the rib even when the lid is pressed on very tightly, while claim 6 ensures that the lid does not come loose even when it is accidentally tipped over.

The inner edge provided according to claim 7 serves to center the lid and can also form a counter bearing for the edge of the container bent inwards by the rib.

By means of the design according to claim 8, the lid is centered before the rib can engage with the edge of the container.

The lid according to the invention is expediently provided with a handle element according to claim 9, which is particularly easy to handle in its design according to claim 10.

The design according to claim 11 allows the lids to be stacked safely, whereby the design of the stacking aid according to claim 12 has proven to be particularly useful.

Claims 13 and 14 describe particularly preferred materials for the cover according to the invention.

An example of the innovation is explained in more detail below using the drawings. They show:

Fig. 1 shows a longitudinal section through a container provided with a lid according to the innovation,

Fig. 2 a longitudinal section through a cover according to the innovation,

Fig. 3 shows section III - III from Fig. 2,

Fig. 4 shows detail X from Fig. 2 on an enlarged scale,

Fig. 5 is a plan view of the cover according to the innovation, and

Fig. 6 Two stacked lids according to the innovation.

Fig. 1 shows a lid 1 according to the innovation, which sits on a thin, commercially available disposable plastic container, such as those used for dairy products such as yogurt, kefir, buttermilk, cream, desserts or the like. The container 2 has a radially projecting, flat disc-shaped edge 3, onto which the metal foil is normally welded. Below the radially projecting edge 3 there is a stiffening area 4, which is essentially cylindrical, has a larger diameter than the rest of the container 2 and merges into the rest of the container 2 with a step 4a.

The lid 1 according to the invention has, as shown in Figs. 2 to 6, a lid base 5 which essentially has the shape of a

a disk. An outer edge 6 projects from the outer peripheral edge of the lid base 5 essentially coaxially to the axis 5a of the lid base 5. The outer edge 6 is designed to be flange-like and has on its inner side facing the axis 5a, evenly distributed around its circumference, three ribs 7 for clamping the lid 1 onto the edge 3 of the container 2, which protrude inwards in the direction of the axis 5a. Each of the ribs 7 runs parallel to the outer edge 6 and in the axial direction over its entire axial length from the lid base 5 to the free end 6a of the outer edge 6. At the free end 6a, the rib 7 is provided with a rounding 7a. The rib 7 essentially has a circular or semicircular cross-section, as shown in more detail in Fig. 3.

At a distance between the ribs 7 and the outer edge 6, an inner edge 8 protrudes from the lid base 5, which is also designed to run around the edge like a flange and runs parallel to the axis 5a. The inner edge 8 is significantly longer in the axial direction than the outer edge 6, but has approximately the same thickness. At the same radial distance from the axis 5a as the free end 8a of the inner edge 8, there is a boundary surface 9a of a recess 9 on the top side of the lid base 5, which serves as a stacking aid so that two of the lids 1 can be stacked on top of one another, as shown in Fig. 6, with the free end 8a engaging in the recess 9 of the lid below and being centered by the boundary edge 9a.

Two further, essentially semi-circular grip recesses 10 are formed in the top of the lid base 5, which are separated by a likewise formed web 11, which serves as a grip element. The web 11 is completely sunk into the inner edge 8, whereby its top does not extend into the recess 9, and its bottom does not extend beyond the free

Edge 8a protrudes so that the handle element does not impair stacking.

The lid according to the invention can be made either from food-grade plastic or from stainless steel or from other suitable materials, whereby it is expedient to choose a material that allows the lid 1 to be manufactured in one piece in all its details.

After opening the container 2 by removing the metal foil, it can be closed or reopened as often as desired using the innovative lid. The lid is simply placed on the upper opening of the container 2, with the inner edge 8 initially dipping into the container 2 in the area of the cylindrical stiffening area 4 and centering the lid so that all ribs 7 hit the edge 3 as evenly as possible. The lid is then pressed on more firmly, with either the edge 3 of the container 2 in the area of the ribs 7 and/or the ribs 7 themselves, which are made of an elastic material for example, being deformed so that the lid is held in place by friction and springback. Since the upper filling openings and rim diameters of such plastic containers essentially have only two dimensions, a smaller one for small cups and a larger one for larger cups, since they are to be filled by the same filling machines as far as possible, it is sufficient to keep two lid sizes in stock, with the larger plastic cups, for example, having an outer diameter on the outer circumference of the rim 3 which is approximately between 94 mm and 95 mm, while this outer diameter for smaller cups is approximately 74 mm to 16 mm, in particular 75 mm. Manufacturing tolerances are then easily compensated by appropriate dimensions of the ribs, for example when using three, symmetrical

metrically distributed ribs 7, these extend to an inner circle which is preferably between 1 mm and 3 mm, preferably 1.5 mm, smaller in diameter than the average outer diameter of the rim 3, i.e. preferably 93 mm or 73 mm. The outer diameter of the inner rim 8 should be smaller than the smallest inner diameter in the stiffening area 4 of the plastic cup to be closed with the lid, whereby for example for large cups with a filling weight of 200 g or more, an outer diameter of about 78 mm can be selected.

In a modification of the described and illustrated embodiments, fewer than three or more than three ribs can be provided. With a longer outer edge or a different shape of the lid base, it may not be necessary for the ribs to extend over the entire axial length of the outer edge if it is ensured that the ribs engage and remain in engagement with the outer circumference of the edge of the container when the lid is pressed on and when the lid is pressed on. The lid can be provided without a handle element or with other handle elements, not stackable or stackable in another way and with an inner edge that is only provided in certain areas, for example. The outer edge does not necessarily have to be ring-shaped either, but can also be provided in certain areas, for example. The lid can also be used for containers other than the dairy product containers described and for containers with differently designed edges (e.g. with a more or less radially elastic edge bead) or without a stiffening area.

Claims (15)

Protection claims 1. Lid for releasably closing a container with a radially projecting edge, in particular a disposable plastic cup, the lid having a lid base, an outer edge projecting axially from the lid base and a connecting device provided on the outer edge for releasably connecting to the edge of the container, characterized in that the connecting device has at least one clamping rib (7) which extends axially over the inside of the outer edge (6). 2. Lid according to claim 1, characterized in that three evenly distributed ribs (7) are provided. 3. Lid according to claim 1 or 2, characterized in that the rib (7) has a circular to semicircular cross-section. 4. Lid according to one of claims 1 to 3, characterized in that the rib (7) is rounded or bevelled at its end (7a) facing away from the lid base (5). 5. Lid according to one of claims 1 to 4, characterized in that the rib (7) adjoins the lid base (5). 6. Lid according to one of claims 1 to 5, characterized in that the rib (7) extends over the entire axial length of the outer edge (6). 7. Lid according to one of claims 1 to 6, characterized in that an inner edge (8) is arranged at a distance from the rib (7) radially inside the outer edge (6). 8. Lid according to claim 6, characterized in that the Inner edge (8) is longer in the axial direction than the outer edge (6). 9. Lid according to one of claims 1 to 8, characterized in that a handle element (11) is provided on the outside of the lid base (5). 10. Lid according to claim 9, characterized in that the The handle element is formed by a web (11) which separates two grip recesses (10). 11. Lid according to one of claims 1 to 10, characterized in that a stacking aid (9, 9a) is provided on the outside of the lid base (5). 12. Lid according to claims 7 and 11, characterized in that the stacking aid has a recess (9) for receiving the inner edge (8). 13. Lid according to one of claims 1 to 11, characterized by its one-piece construction made of plastic. 14. Lid according to one of claims 1 to 11, characterized by its one-piece construction made of rust-resistant steel. 15. Plastic container with a radially projecting edge, characterized by a lid according to one of claims 1 to 14.