A method of producing articles from thermoplastic parisons, comprising:
- cyclically oscillating about a vertical axis a mechanism having at least two adjacent but angularly spaced vertically reciprocable combination parison pickup and mold loading devices, and at least two vertically reciprocable molded article transfer devices angularly spaced from each other and from said loading devices;
- presenting successive parisons at a pickup station located within reach of said pickup and loading devices;
- providing a plurality of molding stations spaced from said pickup station and located within reach of said pickup and loading devices, and each of said molding stations having mold means adapted for receiving and molding the parisons into articles;
- providing an article discharge station spaced from said molding stations and from said pickup station and located within reach of said transfer devices;
- and operating said mechanism and said devices in a step-by-step cycle comprising, in the following order:
- (1) orienting one of said loading devices in a parison pickup position above said pickup station and orienting a second of said loading devices above one of said molding stations, and in coordination therewith orienting one of said transfer devices above a second of said molding stations and orienting a second of said transfer devices above said discharge station;
- (2) lowering said loading devices and transfer devices and thereby picking up a parison at said pickup station by means of said one loading device and loading a parison into said one molding station by means of said second loading device, and in coordination therewith entering said one transfer device into molded article stripping relation to said second molding station and discharging a molded article to said discharge station from said second transfer device;
- (3) raising said loading and transfer devices above said stations;
- (4) turning said mechanism in one direction of oscillation and orienting said one loading device over said second molding station, orienting said second loading device over said pickup station, orienting said one transfer device over said discharge station and orienting said second transfer device over said one molding station;
- (5) lowering said loading devices and said transfer devices downwardly and loading a parison into said second molding station from said one loading device, picking up a parison at said pickup station with said second loading device, and in coordinated relation therewith discharging a molded article to said discharge station from said one transfer device and entering said second transfer device into article stripping relation to said one molding station;
- (6) raising said loading devices and said transfer devices above said stations;
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- (7) turning said mechanism in the opposite direction of oscillation and thereby returning said one loading device to said pickup station, returning said second loading device to said one molding station, returning said one transfer device to said second molding station and returning said second transfer device to said discharge station, for repeating the operating cycle.