It has been proposed to mould hollow articles from chocolate by moulding two components of the article separately and then joining the two components together to form the complete article, sometimes after inserting an object between the two components.

In UK-A-504317 (Shuttleworth) it has been proposed to make chocolate eggs in two portions, filling the two portions with small articles and holding the two portions together by ribbon. The halves are formed in individual half moulds between which is located a plate lying between the rims of the mould halves. Chocolate is introduced into the mould halves and the liquid chocolate flows over the inner surfaces of the mould halves during a spinning process. After solidification of the chocolate the mould halves are separated, the plate is removed, and the moulded chocolate is removed from the mould halves. The plate is formed with recesses at one side and corresponding projections at the other side so that when the solidified halves are brought together at their rims and the projections locate in the recesses.

In another arrangement disclosed in US-A-5635230 (Aasted) there is disclosed a method and apparatus for producing co-operating half moulds of chocolate. In this arrangement a mould is provided for each half and a cooling member is located into the mould after the admission of molten chocolate into the mould to cause the chocolate to solidify and to cause the annular rim of the moulded chocolate to move into a recess to define the rim shape. After the solidified halves are removed from the mould they are joined together along the rim edges.

The prior proposals for making the moulded hollow articles suffer from various disadvantages. They may be expensive in terms of the apparatus requirements, or they may

be simple but inadequate in forming a complete moulded article in which the mould halves are firmly connected together, or both.

It is an object of the invention to provide an improved method and apparatus for moulding hollow articles.

According to the invention, a method of moulding hollow articles comprises lining a pair of complimentary moulds with product to be moulded and between which is arranged to be located a gasket member, and moulded product from each mould is joined together along peripheral edges to produce a closed hollow article, the method including the steps of charging the pair of moulds with molten product, causing the product to line the pair of moulds, solidifying the product, separating the moulds, removing the gasket member from the pair of moulds, heating the product along the peripheral edges to soften the product, and bringing the moulded product in each mould together to join them along said peripheral edges, the gasket member being shaped adjacent the edges of the mould to provide a non- planar portion extending around the edge of at least one of the moulds so that the moulded product formed in said portion extends out of the plane of said peripheral edge prior to joining the moulded products together.

Preferably the gasket member is shaped to provide a groove into which the product passes during lining of the pair of moulds with product, whereby the groove defines a protruding portion in the moulded product. Conveniently the other side surface of the gasket member is of planar shape to form a planar surface on the rim of the associated mould half.

Heating of the edges of the moulded product causes at least the rim of the product to become softened or semi-molten. When the rims are brought together the protruding portion is deformed and is adhered to the other rim.

The protruding portion is located inwardly of the outer surface of the moulded article so that product does not become displaced to the exterior of the assembled moulded product.

Alternatively the gasket member is shaped to provide a stepped profile at the edge of at least one of the moulds whereby a stepped or protruding portion of the rim is provided out of the plane of the rim.

B efore the moulded product is j oined together there may be placed between the mould halves a novelty item, toy or other article or articles.

Usually the pair of moulds includes half moulds of complementary shape and the rims or edges of the moulds are of the same peripheral shape as one another. The gasket member is conveniently sheet material having an opening corresponding to but smaller than the opening into each mould whereby the sheet material projects into the moulds at their periphery.

The co-operating moulds with the gasket member may be lined with product in conventional manner such as by a spinning process by which the assembled moulds are charged with liquid product and are slowly moved about axes inclined to one another causing the liquid product to flow over the internal surfaces of the assembled moulds.

The invention also provides apparatus for making moulded hollow articles comprising a pair of complimentary moulds, a gasket member to be located between the moulds, the moulds each comprising a recess extending from a planar surface which, at the edge of the recess, defines the rim of a moulded product to be formed in each recess, the gasket member being arranged to lie between the planar surfaces and to extend inwardly to project into the respective recesses, the gasket member defining a central opening between the respective recesses and being formed over its projecting portion at at least one side thereof with a non- planar profile on which the moulded product is to be received so that, upon solidification of product, the moulded product protrudes above said surface, the pair of moulds being arranged to be assembled with the gasket member there between; charging means for charging the recesses with molten product, mould moving means whereby the moulds are moved to line the moulds with product, and the pair of moulds being separable and the gasket member being removable so as to present moulded product in the moulds, the apparatus further

comprising heating means to heat and soften the product, the pair of moulds being arranged to be brought together so that the product is joined to produce said article.

Preferably the gasket member is formed with a groove extending around the projecting portion whereby to form a corresponding projection on the rim of one of the mould halves.

Further features of the invention will appear from the following description given by way of example only and with reference to the drawings, in which: Fig 1 shows a longitudinal section through a pair of moulds and an associated gasket in one embodiment of the invention, Fig 2 shows a section corresponding to that of Fig 1 after the moulds have been lined with product, Fig 3 shows an enlarged view of the portion 3 in Fig 2, Fig 4 shows moulded product as contained within the pair of moulds and before joining of the moulded parts, Fig 5 shows a completed moulded article, Fig 6 shows an alternative embodiment of the invention corresponding to Fig 3 of the previous embodiment, Figs 7A, 7B, 7C, 7D, 7E, 7F, 7G, 7H and 71 show various stages in the method of forming moulded hollow articles in accordance with the invention, Fig 8 shows a plan view of a set of moulds for use in the embodiment of Figs 6 and 7,

Fig 9 shows a view in the direction 9 in Fig 8, and Fig 10 shows a plan view of a gasket for the moulds of Fig 8.

Referring to the drawings there is shown moulds in which a hollow chocolate article is to be formed and the resulting hollow chocolate article. Although the product to be made is described throughout as a"chocolate article"it will be appreciated that the apparatus and method of the invention are suited to the production of other mouldable food products.

Referring to Figs 1-5, a mould is shown which is made up of two separate pieces 10,11 constituting a pair of moulds. Each piece 10 and 11 is of different shape but they may be of the same shape. The shape may be arranged to define an egg shape, or other shape such as an animal, cartoon figure, or the like. The moulds 10 and 11 are usually made from plastic sheet in which the mould shapes 10 and 11 are formed as recesses by a blow moulding process, or the like. In one sheet there may be several moulds of the same shape. The sheets 21 carrying the mould shapes 10 or 11 each define a planar surface 15 and the mould shapes are in the form of recesses 12 which extend out of the plane of the surface 15.

Locatable between the sheets 21 and the two mould shapes 10 and 11 and in sealing contact with the adjacent surfaces 15 is a gasket member 13. The gasket member 13 is of planar shape so as to be locatable between the surfaces 15 of the moulds 10 and 11 and in the position shown in Figs 1 and 2 the gasket member protrudes inwardly at 17 into the recesses 12 defined between the moulds 10 and 11 a short distance X. The projecting portions 17 terminate to provide a central opening 14 in the member 13 whereby the moulds 10 and 11 are in communication with one another.

Over the projecting portion 17 of the gasket member 13 the gasket is shaped to provide a non-linear surface, in Figs 1 and 2 a stepped profile 16, at one side, the stepped profile 16 being defined by the gasket 13 being of thinner material at the inner side of the portion adjacent the opening 14 than over the remainder of the gasket member.

In Fig 6 there is shown an alternative form of gasket member 13 which, instead of the stepped profile of the previous embodiment, has a groove 20 of part circular section which extends around the edges of the mould shapes 10 and 11 along one side of the projecting portion 17. In each case, whether with the groove profile 20 or with the stepped profile 16, there is formed in chocolate lining the moulds 10 and 11 a projecting or protruding portion of chocolate within the groove 20 or within the stepped profile 16 which extends above the planar surface 15 of the co-operating moulds 10 and 11. At the opposite side of the gasket 13 the surface is planar and continuous with the associated surface 15. However similar grooves or stepped profiles could be provided in this region also. Although the stepped profile 16 or the groove 20 usually extends around the entire periphery of the moulds 10 and 11 they may be discontinuous.

The method of producing a moulded hollow article will now be described with particular reference to Figs 7A-7I in which the gasket member 13 is of the form shown in Fig 6. However the method using the gasket member 13 of the form shown in Fig 3 is essentially similar.

Usually the mould shapes 10 and 11 are each formed in a sheet 21 containing multiple mould shapes 10 and 11, for example a mould sheet 21 may contain four rows of four shapes in a generally rectangular array, as in Figs 8 and 9. The sheets with each shape are generally the same except that the shapes in one sheet may be different from but complementary to the shapes of the other sheet. The sheets each define a planar surface 15 and are arranged so that the surfaces 15 may be located in face to face contact with one another. In addition the sheets 21 may each have located on them magnets 18 in selected positions so that when the sheets are brought together the magnets 18 on one sheet coact with the magnets 18 on the other sheet to keep the sheets together but permit separation of the sheets, when required.

Initially the sheets 21 are each laid flat with openings 14 into the recesses 12 facing upper most and the sheets 21 may be heated preparatory to receiving molten chocolate into the recesses 12 (Fig 7A). Molten chocolate C is charged into each of the recesses 12 of one of

the sheets 21 (Fig 7B) and a gasket member 13 is applied to the top surface 12 of one of the sheets (Fig 7C). The other sheet 21 is then placed on top of the first sheet in contact with the gasket member 13 (Fig 1 and Fig 7D) thereby forming enclosed spaces defined by the cooperating recesses 12, the sheets being connected together by the magnets 18 and, if necessary, by other clamping means.

The assembled pairs of sheets 21 with their associated mould shapes 10 and 11 are then subjected to a spinning action whereby the molten chocolate within the mould shapes is caused to move over the inner surfaces and then to become adhered thereto by solidification of the mass of chocolate. Such spinning process is of a conventional kind and involves the assembled sheets 21 being mounted on a spinning apparatus whereby the sheets are subj ected to a slow turning movement about two axes at right angles to one another.

At the end of the spinning process the mould shapes 10 and 11 are lined with chocolate C which has cooled sufficiently to adhere to the moulds and to extend around the projecting portions 17 of the gasket 13, as seen in Fig 2 and Fig 7E.

Upon completion of the spinning process the chocolate is further cooled in cooling apparatus so that the chocolate is wholly solidified. The sheets 21 are then separated from one another with the chocolate mould halves located within the recesses 12 and the gasket 17 is stripped from the separated sheets thereby leaving inwardly projecting portions of chocolate at the rims of the mould halves resulting from the projecting portions 17 of the gasket (Fig 4 and Fig 7F) and upwardly projecting portions 20A resulting from the grooves 20 in one mould.

In the other mould the rims are planar (Fig 7G).

The sheets 21, both now presented horizontally with the rims facing upwardly, are subj ected to a heating process whereby the rims of the moulded halves are heated to soften or partially melt the chocolate around the rim edges, including the projecting portions 20A. This would normally be achieved by ducting warm air over the upper surface of the sheets until the required amount of heating has taken place. When heated one of the sheets 21 is inverted and

placed on top of the other sheet so that the moulded product C in one sheet registers with that in the other and the sheet surfaces 15 are in close contact with one another. By this means the edges of the moulded product at said rims are brought into contact with one another and become adhered to one another due to the softened nature of the chocolate and as a result of the projecting portions 20A engaging the rims in the other mould half. This causes the moulded product to become firmly attached to one another (Fig 7H). Further cooling of the chocolate then takes place to ensure that the moulded product solidifies whilst remaining within the recesses 12 in the sheets 21.

The sheets 21 are then separated and the, now integral, moulded articles are removed from the recesses 12 in the sheets, the moulded articles being complete and firmly attached to one another (Fig 71 and Fig 7J).

Subsequently the moulded articles may be wrapped, labelled and otherwise packaged ready for distribution.

If it is required for the moulded article to contain toys, sweets or other items these are inserted before or after the stage of heating the rims, ie when the moulded product is in the condition at Fig 7F and 7G. Upon bringing the sheets 21 together to join the moulded product the items are retained within the article.

It has been found that the moulded article produced by the method and apparatus of the invention is unlikely to come apart inadvertently. The moulding apparatus required is relatively inexpensive and does not require detailed supervision to achieve satisfactory results.

Other rim profiles can be used to bring about the desired result than the stepped and groove profiles described and illustrated. It has been found that provided that the profile is non- linear and proj ects beyond the plane 16 and is inwards of the sides of the recess this achieves satisfactory connection between the mould halves without chocolate escaping to the external part of the article and causing unsightly appearance.