GB1507551A - Blow-moulding machines - Google Patents

Abstract

1507551 Blow moulding ILLINOIS TOOL WORKS Inc 3 May 1975 18618/75 Heading B5A A continuously operating blow moulding machine for tapered preforms comprises a carriage 10 intermittently rotated about a horizontal axis and carrying at equally spaced intervals a series of heated mandrels 25 tapered to match the preforms, a preform loading means 11 supporting a horizontally disposed stack of preforms and arranged to feed them in turn on to a mandrel projecting horizontally from the carriage 10 by means which grip the rim of the leading preform, a split blow-mould 12 mounted to close about a mandrel 25 projecting vertically downwardly from the carriage, and take-off means 13 for reciprocating along a downwardly inclined mandrel to grip a blown article and withdraw it from the mandrel. Two carriages 10 (one behind the one shown in Fig. 1) are rotated on the same shaft and each is fed from a separate stack, Fig. 8, by the same loading device 105 carrying fingers 120 which engage behind the rims of the leading preforms. The device 105 is moved forward by a ram 108 to load preforms on to the mandrels. The rest of the stack is urged forward by continuously running belts 130 on which they rest, but other fingers 110, 111 (Figs. 6, 7, not shown) hold them back. The blown articles are discharged down suction tubes 156, Fig. 9, after fingers 161 are forwarded by a ram 142, cammed into engagement with the articles by surfaces 162a, and retracted to the dotted line position. The preforms are held on the mandrels 25 by suction applied through passages 224 to 228, Fig. 10. The tapered portion 204 of the mandrel is heated by cartridge heater 210 and neck portion 208 is insulated from this by sleeve 216. Thus as the preform body expands the neck portion does not expand and can slide up the cool portion 208. Also an initial gap 205 at the step assists in preventing the end of the preform losing contact with the mandrel during expansion. The blow moulds, Fig. 3, are cooled through passages 88 and have a bottom plunger which is spring biased downwardly to disengage the blown article on mould opening. A pair of moulds is opened and closed by raising and lowering a shaft 50 connected to one half of each mould by arms 66. The pivoted mould mounts 67, 70 of opposite halves of different moulds are connected by links 71, 72 so that the two halves of each mould operate in synchronism.