| 摘要 |
The cardboard tray for foodstuffs has an opening rim (8) in the shape of a flat ring and portions (4') carrying creases, which have reinforcing fillets fastened to said rim and reproducing its shape and are made of the same cardboard constituting the tray, as they are constituted of appendices of the cardboard of the rim of the cup-type container which form a single body with said cardboard along certain sections (8') of the outer edge of the rim which are free of creases. The manufacturing process provides for the following phases:
- Obtaining by die cutting a first cardboard sheet (2) cut according to a contour (3) suitable for obtaining, by deep drawing and thermal forming, a tray (7) of a pre-determined shape, where the outer contours of portions (5) of the initial sheet (2) non destined for creasing happen to be formed like appendices (6;9) capable of superimposing themselves, by bending to the rim (8) of the trya opening at the end of the deep-drawing and thermal forming process.
- Backward bending, after the initial sheet (2) has been subjected to the creasing, deep-drawing and thermal forming phases, of the mentioned appendices (6;9) along the lines (8) belonging to the outer contour of the rim of the tray, until they superimposes themselves to said rim, that they are finally welded to.
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