| 摘要 |
1,135,863. Moulding thermoplastic articles. K. MAGERLE. 12 April, 1967 [21 April, 1966], No. 16700/67. Addition to 971,921. Heading B5A. In a process of moulding the neck of a tubular container, a predetermined quantity of plastics material is extruded as an annular bead from a slot 431 of a nozzle 427 into a cavity 425 formed by mould parts 407, 415 in a holder 401. A cylindrical core or mandrel 435 carried on a turntable is surrounded by a tube section 437 of thermoplastic material and aligned with the mould, whereupon the mould holder and extrusion nozzle are lowered. The extremity of the nozzle abuts the neck 443 of the core, and during further lowering of the holder the extruded head is sheared from the nozzle by the face 423 of the part 411 and deposited around the core neck, Fig. 3, during which time the parts 407 and 415 are forced together against springs 21. The extrudate blank 451 is keyed to the core by a dovetailed annular groove 449. After raising the mould holder, the core is carried to a heating station, Fig. 4, not shown, where a cup-shaped member 461 integral with a metallic member 459 is heated by an induction coil 457 and surrounds the blank and the upper end of the tube section. The heated core is now fed to the moulding station where the tube end is received in a mould section 491 Fig. 5, and the blank is compressed by an upper pair of opposed slides 487 to form a threaded opening 489 of the tube; some of the blank is forced downwardly and fuses with the upper end of the tube. In a modification of Figs. 1-3, the bead is extruded into a cavity of a single piece mould, the extrusion nozzle is retracted to leave the bead at the mould base, the mould is then lowered on to the core and the bead is forced by compres- sed air downwardly on to the core.
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