GB2216864A

GB2216864A - Sealing an array of containers

Info

Publication number: GB2216864A
Application number: GB8905980A
Authority: GB
Inventors: Timothy John Kemp
Original assignee: Plastona John Waddington Ltd
Current assignee: Plastona John Waddington Ltd
Priority date: 1988-03-16
Filing date: 1989-03-15
Publication date: 1989-10-18
Also published as: GB8905980D0; GB8806274D0

Abstract

A plurality of containers are arranged in an array and are sealed simultaneously by a sheet of lidding material. The containers are preferably thermo-formed and of triangular shape of which one angle is a right angle and so that when two containers are placed hypotenuse to hypotenuse they jointly define a square. Pairs of containers can then be separated from square packages made up of two containers connected by lidding material. Alternatively the containers may be square, rectangular or hexagonal. The lidding material is preferably a flexible film or foil which is heat sealed, ultrasonically welded or attached by adhesive to the rims of the container, the rims being arranged in a common plane. <IMAGE>

Description

Improvements Relating to Packaging This invention relates to a packaging, and in particular concerns the packaging of articles, products, foodstuff and the like in domestic packaging containers which are of the type comprising a base, a side wall and a top rim.

Typically such packages will comprise trays and cups, and whilst the invention is not to be considered as being limited thereto, in the majority of cases the packaging containers will be of plastics material, and more particularly will be plastic material containers thermoformed from plastic sheet material.

In the interests of simplicity of description therefore, the packages will be referred to hereinafter as thermoformed containers.

Thermoformed containers are widely known and are used extensively in the packaging of foodstuffs such as margarine, butter, ice cream, food products, yoghurt, pre-prepared products and many other types of consumable items, and such products for human consumption usually have to be protected from the surrounding environment until they are to be consumed. To this end, it is known to provide thermoformed containers with covering lids which may be detachable and reusable with the container, or may be for example in the form of a film or foil sealed to the top rim of the container which must be removed and/or fractured when access to the interior of the container is to be obtained.

The present invention is concerned with the sealing of thermoformed containers using lidding sheet or web material which will normally be flexible in nature and may comprise for example a plastics material film, but within the scope of the invention it is also possible to use a rigid or semi rigid sheet material for the sealing of the thermoformed containers by sealing such material to the container rim.

The present invention in its broadest aspect resides in that a plurality of thermoformed containers are arranged in an array with their rims in a common plane, and applied to the so arranged containers is a sheet lidding material to be sealed to the rims of said containers whereby the containers become connected by means of the sealing material.

By this means, a plurality of containers can be lidded at the same time, and the lidding material will form a connecting means between the individual containers. The containers can therefore be arranged in groups and connected by the lidding material which is extremely convenient for the marketing of the containers as frequently such containers are sold in packs two, three, four or more.

In accordance with the invention, the shape of container is preferably such that when the containers are arranged in array, they fill as far as possible the available area so that there is little or no space between containers thereby minimising wastage of the sealing material.

Therefore, the containers may for example be square or of elongated rectangular form or they may be triangular or hexagonal but in any case the shapes which inters it and fill up a larger area without spaces are preferred.

In one particularly suitable example, the containers are generally triangular of which one angle is a right angle and so that when two containers are placed hypotenuse to hypotenuse, they jointly define a square.

After the process of applying the lidding material to the containers, pairs of containers can be separated from adjacent pairs to form packages of square configuration and made up of two containers connected by the lidding material.

The lidding material preferably is a flexible film or foil which is heat sealed to the container rims or is applied thereto by other sealing means such as ultrasonic welding or in the alternative by means of suitable adhesive.

An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings, wherein Fig. 1 is a perspective view of a container according to and for use in the method of the present invention; Fig. 2 is a sectional elevation of the container shown in Fig. 1, the section being taken on the line A-A in Fig. 1; Fig. 3 shows a plurality of containers shown in Fig. 1 in a particular disposition and after being covered by means of a lidding foil material; Fig. 4 is a sectional side elevation of a portion of the arrangement shown in Fig. 3, the section being taken on the line B-B in Fig. 3; Fig. 5 is a view similar to Fig. 3 but showing how the containers of Fig. 1 can be arranged in an alternative array; Fig. 6 shows in plan view a pair of containers each as shown in Fig. 1, but arranged in yet a further configuration; and Fig. 7 is a view similar to Fig. 3, but showing containers of hexagonal shape.

Referring to the drawings, in Fig. 1 a container 10 is thermoformed from plastic sheet material, and comprises a base 12, a wall 14 and a top rim 16. The rim 16 is outwardly turned as shown in Fig. 2, and as shown in Fig. 3 the container is generally of triangular shape, but with the ends blunted as shown at 18, 20 and 22.

The container defines a triangular shape, of which one angle is a right angle, so that the rim 16 has three sides 16X, 16Y, which are of the same length, and a hypotenuse side 16Z.

In use, the container is filled with the contents and then subsequently is sealed, for example by means of a plastic foil or film 24 as shown in Fig. 3.

In order to utilise the containers as shown in Fig. 1, a plurality are arranged in a particular array, for example as shown in Fig. 3, in which pairs of containers are arranged with their hypotenuses 16Z opposite so that each pair of containers forms a square. The said squares are arranged in abutting contact so as to fill as much as possible of a larger area in which containers are contained. The top rims 16 are arranged in a common plane, and after the containers are provided with their contents, a common sealing film 24 which may for example be a transparent plastic foil is applied over the containers and is sealed to each of the container top rims 16 in order to encapsulate the contents.

It will be seen that by this method the film 24 in fact connects all of the containers, and if they are removed from a jig in which they are held, they will remain connected by means of a film. The film can then be broken, torn or cut so as to form individual packages comprising two or more containers, and such packages can then be made ready for marketing on store and supermarket shelves. The consumer can buy the packages in blocks of any number and separate same, one by one, by severing or fracturing the foil, at his convenience.

Although the individual containers in each package remain connected by means of the film or foil 24, if that film or foil is flexible, the containers can be relatively pivoted as shown in dotted lines in Fig. 4. Fig. 4 also illustrates container contents 26.

Where the film 24 is heat sealed to the rims 16, it will be appreciated that the film 24 and containers must be of compatable material for this heat sealing to be effective.

Film 24 may be a single layer of plastics film or may be a laminate or coated film as required.

Fig. 5 shows yet a further arrangement which can be adopted for the containers shown in Fig. 1 in which the containers are arranged in groups with their hypotenuses adjacent, but the pairs of hypotenuses of pairs of containers are arranged parallel and one shorter side 16Y of one container in one pair is arranged adjacent a shorter side 16Y of one container in an adjacent pair of containers.

Fig. 6 shows an alternative disposition for the pair of containers in a package in which the hypotenuses 16Z of the two containers are still arranged side by side, but one container is displaced relative to the other by an amount D1 to enable the pair of containers to be formed into a package of minimum width D2. Such a pair of containers may suitably be contained in a cardboard sleeve of trapezium shape to suit the container profiles.

In the arrangement shown in Fig. 7, hexagonal shape containers are laid up so as to leave minimum gaps therebetween prior to the application of the sealing film 24 which again is sealed to- the container rims to provide a means of interconnecting the containers.

When the containers are connected by means of the film 2A, the handling of the containers is considerably simplified, and they can be maintained in position relative to each other until such times as the film has been severed or broken.

It will be appreciated that in all cases the container contents must be in the containers 10 before they are sealed by means of the sealing sheet material.

Claims

1. A method of sealing thermoformed containers comprising arranging a plurality of thermoformed containers in an array with their rims in a common plane, and applying to the so arranged containers, a sheet of lidding material which is sealed to the rims of said containers whereby the containers become connected by means of the sealing material.

2. A method of sealing thermoformed containers according to Claim 1, wherein the shape of the containers is such that when the containers are arranged in an array, they fill as far as possible the available area so that there is little or no space between containers thereby minimising wastage of the sealing material.

3. A method of sealing thermoformed containers according to Claim 2, wherein the containers are square, of elongated rectangular form, triangular or hexagonal.

4. A method of sealing thermoformed plastics containers according to Claim 3, wherein the containers are generally triangular of which one angle is a right angle and so that when two containers are placed hypotenuse to hypotenuse, they jointly define a square.

5. A method of sealing thermoformed plastics containers according to any preceding Claim, wherein after the process of applying a lidding material to the containers, pairs of containers can be separated from adjacent pairs to form packages of square configuration and made up of two containers connected by the lidding material.

6. A method of sealing thermoformed plastics containers according to any preceding Claim, wherein the lidding material is a flexible film or foil which is heat sealed to the container rims or is applied thereto by other sealing means such as ultrasonic welding or by means of suitable adhesive.

7. A method of sealing thermoformed containers substantially as hereindescribed with reference to the drawings.

8. Sealed theremoformed plastics containers sealed by the process according to any one of the preceding claims.