GB1115086A - Improvements in blow-moulding machines - Google Patents

Abstract

1,115,086. Blow-moulding; driven rotary table. SAFLEX Ltd. 21 Oct., 1966 [24 Nov., 1965], No. 49870/65. Heading B5A. An extrusion-blow moulding machine comprises a rotary table (4, Fig. 1), a plurality of radially openable moulds (5) at equal angular intervals about the centre of the table, the centres of the mating planes of the moulds being on a common pitch circle of the table, a stationary, extruder. (8) producing a tubular thermoplastic parison, the nozzle thereof (7.) being aligned with the circle in which the moulds are mounted, the table being rotated and successively indexed at positions where a mould is aligned with the nozzle (see Fig. 2, not shown), by means comprising a driven rotary member constituted by the table or coupled thereto (e.g. 6, Fig. 3) having equally angularly spaced radial slots (22) opening at its circumference, and a driving member (23), rotatable about an axis parallel to that of the table and having equally angularly spaced drive elements (e.g. pins 24) preferably at 120 degrees for engagement in the slots, the drive elements entering and leaving said slots while moving normally to the circumference of the driven member one thereof leaving one slot as another thereof enters another slot. There is preferably one blowing nozzle (17) for each die, carried by the table, the nozzles being shifted between a position clear of the line of motion relative to the extruder nozzle (7) and an operative position where the nozzle is engaged with an end of the tubular parison carried in the moulds (Figs. 5, 6, not shown). The extrudate may be severed by a blade (29) reciprocable in the gap between extruder and mould.