WO1994022353A1

WO1994022353A1 - An improved structure for a transportable tray of the type with selective thermal sealing action

Info

Publication number: WO1994022353A1
Application number: PCT/EP1994/000907
Authority: WO
Inventors: Francesco Grillo
Original assignee: Francesco Grillo
Priority date: 1993-03-29
Filing date: 1994-03-23
Publication date: 1994-10-13
Also published as: ITTV930037A1; IT1266409B1; ITTV930037A0

Abstract

A transportable tray comprises two half casings (1, 2) divided into compartments (a, b) and fashioned from an insulating plastic material, matched one to another so as to form a tray (1) with a lid (2) and secured thus by way of peripheral fastening means, wherein one half casing (1) affords at least one container (7, 8) internally of one compartment (a), and the other half casing (2) affords a corresponding cavity (7', 8') located to coincide with the container (7, 8) of the first when the two are assembled and secured. The improvement consists in furnishing at least one half casing (2) with peripheral seals (10) extending around each cavity (7', 8') of at least one compartment (a), positioning a sheet of non-toxic paper (12) or plastic material, plain or profiled and matched in opposition to the containers of each compartment, in such a way as to remain interposed between the two half casings when assembled and secured, and using stackable cups (11) inserted into corresponding containers (7, 8) of the tray, each furnished with locating and spacing means (11'') positioned immediately below a horizontally projecting flat peripheral rim (11').

Description

An improved structure for a transportable tray of the type with selective thermal sealing act ion

DESCRIPTION

The present invention relates to an improved structure for a transportable tray of the type with a selective thermal sealing action.

In particular, the improvement disclosed is applicable advantageously, though not exclusively, to the large scale distribution of meals ready for consumption, relating as it does to a compartmentalized insulating container for hot and/or cold foods.

The prior art in this field embraces transportable containers of the type in question, the design of which is based on the familiar principle of interposing a layer of insulating material between the recipient proper and the surrounding environment. As an item of background information, the first thermally sealed type of container to come into widespread use as a means predominantly of distributing hot beverages was the "Thermos" flask; as is well known, this consisted of a heat-insulated recipient, generally in the form of a bottle fashioned from glass with a double wall, the space between the inner and outer wall being evacuated and the vacuum-encapsulatinq surfaces silvered in order to reduce heat loss.

With the need to keep other types of food products at a given temperature, for example solids distributed on a takeaway or delivery basis, providers of services have been led to investigate the possibilities of plastic materials, which are decidedly less costly ano easier to work than glass. A first type of material, of which the particular properties recommended it as being well suited to the purpose, was expanded polystyrene, now widely used for the distribution of takeaway beverages and of solid fooos both hot and cold, typically ice cream in the latter instance.

The drawbacks experienced with these earlier solutions consist, on the one hand, in the fact that it is not possible to maintain different temperatures to suit dissimilar types of food within the one container, and on the other, in the fact that such containers do not afford a structure suitable for the transportation of complete meals for distribution to larger communities, such as hospitals. In the case of ready-to-eat delivery services, certain foods (typically main courses) need to be maintained and served at a certain temperature, and others (such as dessert) at a temperature different to the first, for example cooler. This effect is not obtained with the conventional type of tray, albeit compartmentalized, and instead, a single temperature becomes established uniformly over the entire contents of the container, irrespective of the type of food. The problems briefly outlined above are addressed in Patent n 1 235 116, property of the same applicant; this discloses a container structure comprising a tray as the container and an inverted tray type moulding as the lid, both embodied in a plastic material, composed of an inner shell and an outer shell encompassing an insulating void, filled with plastic material, which is characterized in that the tray and the lid mouldings exhibit identical and symmetrical divisions essentially creating compartments and compartment covers, and in that at least one or a plurality of the compartments and corresponding compartment covers will be furnished with a raised peripheral bead which, when the lid is positioned over the tray, produces an internal sealing action isolating the other adjacent compartment or compartments in such a way as to establish a separation into two areas of different temperature.

Nonetheless, there are drawbacks discernible even in the patent solution mentioned above. In particular, one still has the possibility, while the container is in transit, that liquids or foods can spill over from one compartment to another, or from one cup to an adjacent cup internally of a compartment isolated to maintain a different temperature from another. The consequence of such a situation in practical terms is that the quality and organoleptic properties of the food are adversely affected. In an attempt to solve this problem, albeit in limited measure, it was thought appropriate to seal the cups individually with plastic film when inserted into the respective cavities of the tray. Conversely, such an expedient brings other drawbacks, among which the need to add a specific processing step, resulting in longer delivery times, and more especially, higher costs (purchase and maintenance of packaging machines, increased manning requirements, extra expenditure on film material, drop in food temperature during the packaging cycle, utilization and cost of thermally sealed containers, etc...). Another drawback is that the compartment containing hot foods may well produce condensation which, notoriou sly, affords conditions especially favourable for bacteria and also results in the precipitation of liquids back onto the food itself. Other drawbacks of a less critical nature can include a certain difficulty in cleaning the compartments, and a lack of rationality in the way that foods prepared for distribution are ordered in line. Finally, considerable care must be taken currently to ensure that the correct quantity of food is dispensed into each of the single cups inserted into the cavities of the tray, to avoid overfilling. In effect, overfilling can result in foods spilling from one cup to another during successive steps of the preparation, or at best, in the tray being soiled and presenting a less than favourable aspect to the consumer. The object of the present invention is to overcome the drawbacks mentioned above.

This object and others besides are realized, according to the present invention, in an improved structure for a transportable tray as recited in the appended claims; the tray is of the type affording a selective thermal sealing action, comprising two half casings divided into compartments and fashioned from an insulating plastic material, matched one to another so as to form a tray with a lid and secured thus by way of peripheral fastening means, wherein one half casing affords at least one container internally of one compartment, and the other half casing affords a corresponding cavity located to coincide with the container of the first when the two are assembled and secured.

The improvement disclosed consists in:

-furnishing at least one half casing with peripheral seals extending around each cavity of at least one compartment;

-positioning a sheet of non-toxic paper or plastic material, plain or profiled, matched in opposition to the containers of each compartment, in such a way as to remain interposed between the two half casings when assembled and secured;

-utilizing stackable cups, inserted into corresponding containers of the tray, each of which is furnished with locating and spacing means positioned immediately below a horizontally projecting fla t peripheral rim.

The features in question reflect a notable inventive step constituting an improvement on the prior art and bringing several advantages. Firstly, the adoption of a sheet of non-toxic paper or plastic material positioned over the cups: net only can the uneconomic process of sealinq with plastic film be eliminated, but also, the hermetic action generated between the sheet and the seals provided in the lid affords better guarantees against any accidental spillage of food and liquids. The seals themselves are easily removod from their respective seatings and thus perfectly in compliance with standards requiring sterilization in an autoclave. As regards the geometry of the sheet, the matching profiles have the effect of creating a compensation chamber, dispersing vapours that form and thus avoiding any precipitation onto the foods. Moreover, these same profiles afforded by the non-toxic sheets considerably increase the capacity of the single cups. Finally, the special shape of the cups results in greater rigidity, bringing benefits in terms of better handling and a more efficient operation of the automated dispensing equipment by which the single cups are filled with the corresponding portions of food.

The features and advantages of the invention will now be described in detail strictly by way of example with reference to the accompanying drawings, in which:

-fig 1 is the plan view of one half casing, and in particular the base or tray accommodating the cups in which foods are contained;

-fig 2 is the plan view of a half casing matched to the half casing of fig 1 and functioning as a lid, fitted with seals;

-fig 3 is the section through X-X in fig 2;

-fig 4 is a plan view of the improved structure showing the tray and lid assembled and secured;

-fig 5 is a front elevation of the improved structure showing the tray and lid assembled and secured;

-fig 6 shows a corner portion of one of the seals, viewed in perspective;

-fig 7 illustrates a stackable cup serving to contain foods, seen in plan from above;

-fig 8 is the section through Y-Y in fig 7;

-fig 9 is a front elevation of the cup shown in fig 7; -fig 10 shows a plurality of cups as in fig 7, stacked one inside another;

-fig 11 illustrates a profiled sheet positioned between the half casings and over the cups, seen in perspective from above;

-fig 12 illustrates a sheet similar to that of fig 11 but in an alternative embodiment, viewed in perspective from above .

Referring to the drawings, th e invention relates to an improved structure for a tray of the type affording a selective thermal sealing action, denoted A, which is composed of two half casings 1 and 2, the one fitting exactly over the other, fastened together around the periphery by securing lever means pivotably associated with the sides of one half casing and designed to snap over a corresponding edge projecting from the other half casing. The structure of the half casings 1 and 2 is obtained by moulding a first outer shell 3 in rigid plaεtiw material, e. g. ABS, into which an insulating material 4 such as expanded polyurethane will then be injected, and a second shell 5 positioned internally of the first and functioning as a holder, which determines the layout and geometry of the compartments and the single containers or cavities; this inner shell 5 will be shaped as deemed appropriate and is fashioned by a coextrusion of non-toxic materials, preferably ABS and methyl acrylate. The shape of the bottom half casing 1 is such as to allow the creation of two compartments, denoted "a" and "b" serving to contain foods consumed at different temperatures, for example warm/hot foods in compartment "a" ar.o cold foods in compartment "b". The same applies in At case of the top half casing 2, which constitutes the lid of the composite tray and is shaped in such a way as to accommodate a raised bead 6 afforded by the first half casing 1, by wnich the two compartments "a" and "b" are isolated one from another. Observing the bottom half casing 1, the compartment denoted "a" is intended to contain hot dishes (main courses) and comprises three depressions or cavities, two of which denoted 7 exhibiting smaller dimensions, disposed side by side, and a third denoted 8 of larger dimensions disposed transversely to the user. Each of the three cavities 7 and 8 is surrounded on all sides by a flat surface approximately one centimetre wide. Being positioned directly over the first half casing 1, the top half casing 2 naturally affords corresponding depressions or cavities, denoted 7' and 8', although shallower than the cavities 7 and 8 of the first. Each of these matching cavities 7' and 8' is surrounded by a peripheral groove 9, adjacent to the edge, in which to anchor a respective silicone rubber seal 10. Whilst the contour of the seal 10, as viewed in plan, will vary according to the particular cavity, the cross section remains the same throuqhout. More exactly, the seal 10 exhibits a monolithic spine 10' insertable into the groove 9, and uppermost, a double lip profile 10'' consisting in parallel flanks separated by a central channel 10''' . The spine 10' also exhibits a rib 10" that serves to induce a measure of deformation in the seal 10 and thus increase the frictional contact with the walls of the groove 9, enhancing grip.

The cavities 7 and 8 of the bottom half casing 1 are designed to accommodate specially shaped cups 11, as indeed is the adjacent compartment "b" also. According to the invention, the single cup 11 exhibits a flat peripheral rim 11' occupying substantially the same plane as the flat surfaces surroundinα the cavities 7 and 8, and projecting a distance sufficient to ensure stable contact with the corresponding seal 10 once the top half casing 2 has been positioned over the first half casing 1. Viewed in section, the cup 11 is tapered toward the base for ease of stacking, and more exactly, the side walls of the cup exhibit a stepped profile, composed of alternating horizontal and substantially perpendicular or at least marginally angled portions, of which the effect is to establish a shape narrowing toward the base, though more importantly, to create an essentially annular stiffening structure. The cup 11 also comprises a plurality of teeth 11'' positioned immediately below the projecting rim 11', coinciding preferably with each corner, which project downwards and are created by forming small depressions 11''' in the rim itself. Accordingly, the teeth 11'' function as spacers serving to distance one cup 11 from the next, whilst the depressions 11''' function as convenient locating points and prevent any accidental misalignment when stacking.

Finally, the improved structure comprises a thin sheet of non-toxic paper, plastic or other related material, which may be profiled as shown in fig 11, or plain as in fig 12. As discernible from fig 11, the profiled sheet 12 exhibits a set of hollow panels raised above a flat surrounding surface; these are matched exactly (in opposition) to the cavities 7 and 8 of the bottom half casing 1, hence comprising two smaller panels 7" and one larger panel 8". With the single disposable cups 11 inserted into the correspondi ng cavities 7 and 8, it suffices to position a sheet 12 or 12', taking care to arrange the panels correctly in the case of a profiled type, and then close the tray by fitting the top half casing or lid 2, in such a way that the seals 10 bear down firmly both on the sheet 12 or 12' and on the flat rim 11' of each cup.

Claims

1) An improved structure for a transportable tray of the type affording a selective thermal sealing action, comprising two half casings divided into compartments and fashioned from an insulating plastic material, matched one to another so as to form a tray with a lid and secured tnus b y way or peripheral fastening means, wherein one half casing affords at least one container internally of one compertmen and the other half casing affords a corresponding cavιty located to coincide with the container of the first when the two are assembled and secured,

characterized in that it comprises:

-peripheral seals incorporated into at least one half casing, extending around each cavity of at least one compartment;

-a sheet of non-toxic paper or plastic material, plain or profiled, matched m opposition to and positioned directly over tne containers of each compartment in such a way as to remain interposed between the two half casinqs when assembled and secured;

-stacking cups singly insertabie into corresponding containers of the tray, each of which is furnished with locating and spacing means positioned immediately below a horizontally projecting flat peripheral rim.

2) An improved st r ucture as in claim 1, wherein the peripheral seals extending around each cavity of the compartment are associated with a part of tray intended to contain hot foods.

3) An improved structure as in claims 1 and 2, wherein an area (a') of the lid half casing (2) positioned over the part of the tray intended to contain hot foods is embodied with peripheral grooves (9) coinciding with and mirroring the outline of the containers afforded by the relative compartment of the first half casing (1). 4) An improved structure as in claim 3, wherein the peripheral grooves (9) serve to accommodate respective seals (10) each, comprising a monolithic spine (10') insertable stably into the relative groove (9), of which the topmost part extends upwards into a double lip profile (10'') with parallel flanks compassing a central channel (10'''), and the lateral surfaces exhibit at least one rib (10").

5) An improved structure as in preceding claims, wherein the bottom half casing (1) affords cavities (7, 8) internally of which to insert respective disposable food containing cups (11), each of which exhibits a flat projecting peripheral rim (11') extending outwards and occupying substantially the same plane as the surface surrounding the corresponding cavity.

6) An improved structure as in claim 5, wherein the disposable cup (II) is tapered toward the base, with side walls exhibiting a stepped profile composed of horizontal portions alternated with substantially perpendicular or at least, marginally angled portions. 7) An improved structure as in claims 5 and 6, wherein each cup (11) is furnished with teeth (11'') positioned immediately below the projecting peripheral rim (11'), coinciding preferably with the respective corners, and affording locating and spacing elements such as will allow one cup to be stacked neatly on top of another. 8) An improved structure as in claim 6, wherein the teeth (11'') project downward and are formed by forcing small depressions (11''') in Ae peripheral rim (11') . 9) An improved structure as in preceding claims, wherein the sheet of non-toxic paper or plastic or other related material is of minimal thickness and of profiled embodiment, exhibiting a set of hollow panels raised above a flat surrounding surface and matched exactly, in opposition, to the cavities (7, 8) of a compartment (a) afforded by the bottom half casing (1). 10) An improved structure as in preceding claims, wherein the two half casings (1, 2) are offered one to another in a matching fit and fastened peripherally by way of lever means pivotably associated with three sides of one half casing and designed to snap over a corresponding edge projecting from the other half casing, whilst the fourth and foroardmost side remains free to accommodate identifying labels .