STACKABLE TAPERING TRAY

Abstract: A stackable, tapering tray including a bottom (2) and at least four side walls (7-10) folded up along crease lines (3-6) in the bottom, said walls having at their upper edge an extension in the form of a slopingly downwardly folded edge flange (15) for co-operation with a lid, which can close the tray (1). The corner areas (17, 18, 27) included in the corner structures (16) of the tray (1) are inwardly folded, and two of said corner areas each have an extension in the form of a downwardly folded flange (21, 22) substantially at right angles to the bottom (2), said flange merging preferably undivided into the slopingly downwardly directed edge flange (15). Free lower edge portions (25) of downwardly folded flanges (21, 22) from the corner areas (17, 18) form stacking abutments against underlying trays (1) stacked one in the other.

Description: ■qt-af-.kah-lfi taperinσ trav The present invention relates to a stackable, tapering tray including a bottom and at least four side walls folded up from crease lines on the bottom, the w-alls having on their upper edges an extension in the form of an edge flange folded slopingly downwards for co-operataion with a lid, which may be used for closing the tray. The object of the present invention is to provide a tray of the kind mentioned in the introduction, which can be readily stacked before use in correspondingly formed empty trays, the corner structures of which can be rearranged with simple hand movements so that the side walls of the tray can be folded outwards to form a plate. The tray in accordance with the invention is intended for use in conveying and storing preferably ready-prepared food, and as a plate at the place of consumption. The rearrangement may take place by pressing the respective corner portion downwards from above, either one after the other, or all for corner portions together, the joint thus being released to permit folding out the tray sides. Since the tray has a flange going all the way round, a very close seal can be achieved between a lid placed over the tray opening, which prevents desiccation of the tray contents. When the flange is formed without any division round the entire tray blank there are no edge cuts in the tray itself, or in the area adjacent its opening, whereby the penetration of fat into the carton blank forming the tray is prevented. The flange may also be used for locking a lid against the tray opening with the aid of flaps formed on the lid, these flaps snapping in under the downwardly directed free end edge of the edge flange. Due to the present invention there is now achieved a tray which serves its purpose in an excellent way, while it is simple to produce at the same time. Essentially distinguishing the invention are the characterizing features, which are disclosed in the accompanying claims. The invention will now be described in detail with reference to the accompanying drawing, on which Fig. 1 is a schematic perspective view of a preferred embodiment of a tray in accordance with the present invention. Fig. 2 illustrates the development of the blank for the tray illustrated in an erected state in Fig. 1, Fig. 3 is a partial side view, to an enlarged scale, of three trays, of which two are stacked one in the other and where a stapling abutment engages against the upper edge portion of the bottommost tray, and Fig. 4 is a partial perspective view, to an enlarged scale, of two trays which are stacked one in the other, where it will be seen how these trays are guided into engagement against each other by the inwardly folded corner areas, with the aid of the centrally situated triangular corner area included in the corner structure. A preferred embodiment of a tray 1 in accordance with the present invention is illustrated in Fig. 1, the tray being stackable in a correspondingly formed tray, due to its tapering configuration, and including a bottom 2 with four side walls 7-10 folded up from the bottom along crease lines 3-6. Via edge crease lines 11-14 the side walls are each extended by an edge flange 15 folded slopingly downwards, this flange being formed in one piece or without any divisions in the illustrated embodiment, and extending around the entire blank forming the tray 1. The edge flange 15 is intended for co-operation with a lid, which can be closed over the tray 1, although it is not shown on the drawing. The corner structure 16 of the tray 1 includes at least two corner areas 17, 18 which are inwardly folded substantially symmetrically along the bisectrice of the corner, and which each has an extension in the form of a flange 21, 22, downwardly folded along an edge crease line 19, 20 and substantially at right angles to the bottom 2. The flanges 21, 22 are mutually contiguous, and e.g. with the aid of thermosetting, are fixed to each other and merge undivided into the edge flange 15 via crease lines 23. The edge crease lines 19, 20 of the contiguous flanges 21, 22 together form an upper edge 24 in the respective upper edge portion of the corner structure 16, said upper edge 24 being able either freely to project inwardly in the tray 1 or be folded and fixed against one of the side walls 7,8 or 9,10. The free lower edge portions 25 of the downwardly folded flanges 21, 22 of the corner areas 17, 18 form stacking abutments against underlying trays 1 stacked in each other.* To facilitate stacking of empty trays 1 one in the other before use, the bottom corners are bevelled so that the bottom crease lines 3-6 are connected in pairs to each other by a short connection crease line 26, forming an angle of 45° to the extension of the respective bottom crease line. The crease line 26 defines the base of a centrally situated triangular central field 27, the apex portion of which merges into a crease line 28 connecting the downwardly folded flanges 21, 22 of the adjacent corner areas 17, 18. Fig. 2 illustrates how the blank forming the tray 1 appears when developed. The triangular corner centre areas 27 are delimited from the two adjacent corner areas 17, 18 along crease lines 29, 30 and the corner area 17, 18 is in turn connected to adjacent side walls along the respective side wall crease line 31, 32. The formation of the corner portion is illustrated in Fig. 3 in a side view to an enlarged scale. It will be seen here how the edge portions 25 form stacking abutments for engaging against the upper edges 24 of the underlying tray 1. In Fig. 4 there is illustrated schematically and to an enlarged scale how the trays 1 are guided into engagement with each other during stacking, with the aid of the triangular, corner, central field 27 included on the corner structure 16. The corner structure 16 may of course be formed without this area 27 also, and in such cases the bottom crease lines 3-6 meet at right-angular corners, a centrally disposed corner crease line then extends from the intersection point of the respective bottom crease lines, instead of the crease lines 29 and 30, so that it merges rectilinearly into the crease line 28 which delimits the flanges 21, 22 of the corner fields 17 and 18. In the latter embodiment with acute bottom corners/ the inwardly folded side surfaces of the corner areas 17, 18 engage against each other and may be optionally fixed into engagement with either of the adjacent side wall surfaces 7, 8 or 9, 10.

Claims: Claims 1. Stackable, tapering tray including a bottom (2) and at least four side walls (7-10) folded up from it along bottom crease lines (3-6) , the side walls having at their upper edge an extension in the form of an edge flange (15) folded slopingly downwards for co-operation with a lid, which can be used to close the tray (1) , characterized in that the corner areas (17, 18, 27) included in the corner structures (16) of the tray (1) are inwardly folded, that two of said corner areas (17, 18) each has an extension in the form of a flange (21, 22) downwardly folded substantially right angles to the bottom (2) , this flange merging in preferably undivided state into the slopingly downwardly folded edge flange (15) , and in that free lower edge portions (25) of the flanges (21, 22) downwardly folded from the corner areas (17, 18) form stacking abutments against underlying trays (1) stacked one in the other. 2. Tray as claimed in claim 1, characterized in that at least two inwardly folded opposing corner areas (17, 18) in the respective corner structure (16) project substantially symmetrically inwards into the tray (1) along the bisectrice of the respective corner. 3. Tray as claimed in claim 1 or 2, characterized in that its bottom corners are made blunt, whereby the bottom crease lines (3-6) at the corners are connected by a connecting crease line (26) forming an angle of 45° to the extension of the respective bottom crease line, and delimiting the base of a centrally situated triangular corner area (27) included in the corner structure (16) , the apex portion of this area merging into a crease line (28) connecting both downwardly folded flanges (21, 22) forming stacking abutments and connecting both adjacent corner areas (17, 18). 4. Tray as claimed in any one of the preceding claims, characterized in that it is retained in its erected state by thermosetting of the mutually adjacent side surfaces of the downwardly folded flanges (21, 22) of the corner areas (17, 18).

Inventors: PERSSON KARL RUNE, PERSSON, KARL, RUNE
Applicants: DUNI BILA AB, DUNI BILAO AB
Application year: 1986
Main classification: B65D21
IPC codes: B65D5