| 摘要 |
1338680 Blow-moulding non-nestable containers ILLINOIS TOOL WORKS Inc 19 April 1971 [19 Feb 1970] 21880/71 Heading B5A Non-nestable containers are formed from thermoplastic nestable containers at ambient temperatures by heating below the rim thereof so that no heat is transmitted to the rim which retains its shape, and expending the heated, deformable portion in a mould so that the size and shape of the rim portion is unchanged. The nestable container 10, Fig. 2, is placed on a mandrel 54, heated by element 55 and lowered between mould halves 80, 82 which are closed around it and is expanded by air blown through porous mandrel 54 against mould surface 88 to form the non-nestable container. After mould opening (Fig. 4, not shown), the product is left on knockout plunger 84. A vacuum may be drawn through the porous mandrel 54 which may be of sintered bronze, to hold the nestable container 10 thereon in close conformity therewith during heating. The rim portion 18 is sealingly pinched between mould surfaces 94, 96, 98, section 104 of mounting base 58 and 0-ring 66, heat being prevented from reaching rim 18 by insulator section 56. The nestable container 20 may be thermoformed from a sheet. Mould halves 80, 82 may be cooled. |
