Plant for blow-moulding plastic containers, particularly bottles

A blow-moulding plant for making plastic containers (2) from respective parisons (3), comprising:

• a blow-moulding line (7) equipped with a plurality of moulding units (15), each comprising at least two cavities (19) for blow-moulding respective containers (2), the moulding cavities (19) of each moulding unit (15) having respective first longitudinal axes (19a) positioned at a first predetermined distance (D2) from each other;
• a flexible feed conveyor (41) which is equipped with a plurality of members (43) for picking up and transporting respective parisons (3) and which extends through a thermal conditioning device (38);
• a parison (3) transfer device (39) coupled to the blow-moulding line (7) at a first transfer station (13) for transferring the parisons (3) to the molding units (15) and coupled to the flexible feed conveyor (41) at a second transfer station (40) for receiving the parisons (3);
• a plurality of pick-up and transfer members (43) associated with the flexible feed conveyor (41) for moving the parisons (3) individually along a predetermined path,
• wherein the flexible feed conveyor (41) extending through the thermal conditioning device (38), at the second transfer station (40), is shaped in such a way that couples of consecutive parisons (3) engaged with the respective pick-up and transfer members (43) of the flexible feed conveyor (41) are spaced on the flexible feed conveyor (41) according to a spacing (P1) that is equal to the first distance (D2) so that they can be picked up directly from the transfer device (39) and put in the cavities (19) of the corresponding molding unit (15),
• wherein the flexible feed conveyor (41) comprises a chain arranged in closed loop and having a succession of rotating joints, each joint defines a vertical rotation axis, each pick-up and transfer members (43) has (i) a holding structure connected at two consecutive rotating joints of the chain whereby it is hooked up to the conveyor (41) to project outwardly from the chain loop in cantilever fashion, and (ii) a mandrel (47) pivotally coupled to the structure to rotate about a vertical axis,
• wherein the chain comprises at least a central portion defined by a plurality of chain links mashed with the rotating joints, an upper portion defined by a first plurality of pins extending from respective rotating joints and projecting upward from said central portion, and a lower portion defined by a second plurality of pins extending from respective rotating joints and projecting downward from said central portion,
• wherein the holding structure of each pick-up and transfer members (43) has an upper arm connected to two consecutive pins of said first plurality of pins and a lower arm connected to corresponding two consecutive pins of said second plurality of pins.