GB1445161A - Containers - Google Patents

Abstract

1445161 Containers BELLAPLAST GmbH 5 Sept 1973 [6 Sept 1972 11 Jan 1973] 41800/73 Heading A4A A container 1 e.g. a cup, plate, or dish, is made of thermoplastics sheet and has a protruding stacking rib, formed by a fold 5 not substantially thicker than twice the thickness of the sheet. Legs of the fold 5a and 5b are pressed close together. The container has a bottom 3, which may be stiffened by corrugations 6, a frusto-conical wall 4 which may incorporate a horizontal step (26), Fig. 3 (not shown) and a surrounding rim 2. The rib (15), Fig. 2 (not shown) may be formed in the rim, in the step (25) Fig. 3 (not shown), or in the bottom 5, and the bottom may be divided into several portions by stiffening ribs (32, 42a, 42b). Several annular or circular stacking ribs (35a, 35b, 45a, 45b, 45c) may be provided Figs. 4B, 4C (not shown). The stacking ribs are formed by a moulding tool, divided into at least two parts (52, 53) Fig. 5, (not shown) which move axially and are spaced apart to form a groove to accommodate the rib; the groove sides may be parallel to each other, and slanted at an acute angle to the axis of the tool. The moulding forms a depression (56) in the container and movable forming portion (53) rises, lifting the bottom to form the rib. It is stated that ejectors eject the container when the portions return to their original positions. The moulding tool (52, 53) may include a heat insulating rubber insert (57) adjacent the rib-forming groove, the insert retaining heat during the moulding operation.