A one-step hydraulic blow molding system and method for forming a preform and a liquid filled container from the preform. The machine and method include a sealing mechanism that forms a seal primarily utilizing compressive forces in an axial direction to prevent the leakage of liquid blow medium. The sealing mechanism includes an axial end face of a forming head and an upper axial surface of a neck ring.

In one embodiment of this invention, a blow nozzle, which introduces blow air into a molded article in which a flange portion is supported by a blow cavity mold, includes a nozzle main body and an outer nozzle. The outer nozzle includes a first surface brought into press contact with the flange portion and a second surface disposed further outwards in a radial direction than the first surface and being brought into contact with the blow cavity mold. From when the nozzle main body is moved and the first surface is brought into contact with the flange portion to when the second surface is brought into contact with the blow cavity mold and the movement of the nozzle main body is stopped, the first surface of the outer nozzle is overdriven so that the flange portion is airtightly sealed by the first surface.

To regulate, in blow molding device using liquid, such as beverage, cosmetic product, and pharmaceutical product, filled in final product as pressurized liquid, head space in container which is filled with content liquid during molding to be predetermined volume, provided is blow molding device including blow nozzle configured to tightly communicate with mouth tubular portion of preform. In state where rod is disposed to be inserted into blow nozzle and where tip portion of rod is inserted into preform, pressurized liquid is supplied into preform via tubular introduction path formed by blow nozzle and rod, thereby expandingly shaping container in accordance with cavity of metal mold. When container is shaped and supply of pressurized liquid is stopped, rod is disinserted from container, and according to shape and insert position of tip portion of rod, head space of shaped container that is filled with liquid is regulated to be predetermined volume.

A method for forming and filling a container with liquid. The container being formed from a preform located within a mold and the method utilizing a hydraulic blow molding device that is coupled to a source of the liquid, which is used as the blow molding medium. The hydraulic blow molding device has a blow nozzle and a member that is extended from a retracted position to a position within the preform. A blow nozzle engages in fluid tight communication with an open end of the preform so as to provide a sealing engagement of the blow nozzle with the preform. The liquid blow medium is injected into the preform so as to form the container after sealing engagement of the blow nozzle with the preform. The member initiates its advancement into the preform prior to the time of sealing engagement of the blow nozzle with the preform.

A nozzle for forming a container preform into a plastic container includes a cylindrical portion having a seal configured to engage with a stepped interior of a finish portion of a preform.