Method for cooling heated molds from a machine for molding containers

Method for cooling heated molds from a machine (10) for molding containers from thermoplastic material by stretch blow molding hot preforms by means of at least one pressurized fluid, with said rotary-type machine (10) comprising at least molding units (12), each comprising at least one mold and that are arranged on the periphery of a carousel (14) that can be driven in rotation around an axis (O) of rotation of the machine, with each molding unit (12) comprising at least a blow-molding device (20) integrating a stretching rod (22), a heating element (34) associated with the mold (18) of the unit for heating it, with said mold (18) comprising at least two half-molds (24) that each comprise an inner molding face (30) and that are respectively mounted on movable supports (26) around an axis (A) between at least one open position and one closed position of the unit, in which said inner faces (30) of said at least two attached half-molds (24) delimit together at least a portion of a cavity (16) for molding the container,

• wherein said cooling method comprises, for cooling said molds (18), introducing, selectively, at least one cooling fluid into a volume inside the molding cavity (16) of some of the molding units (12) when the selected molding units are in a closed position such that, after the carousel (14) is stopped to immobilize them at least during said cooling step, the molding units (12) are in a predetermined cooling zone, and wherein the cooling fluid is delivered at a lower pressure than a pressure of the pressurized fluid for blow molding.