Blow nozzle and blow molding machine

A blow molding machine that blow molds the molded article having the flange portion at the neck portion thereof into a hollow container, the blow molding machine comprising:

• the blow cavity mold which supports the flange portion of the molded article and in which the molded article is disposed within a cavity where the hollow container is blow molded;
• and
• a blow nozzle that introduces blow air into a molded article in which a flange portion provided around an open neck portion is supported by a blow cavity mold, the blow nozzle comprising:
• a nozzle main body moved upwards and downwards;
• and
• a cylindrical outer nozzle connected integrally to the nozzle main body and disposed around a circumference of the neck portion,
• wherein the outer nozzle includes:
• a first surface brought into press contact with the flange portion and continuing in a circumferential direction;
• and
• a second surface disposed outwards in a radial direction than the first surface and being brought into contact with the blow cavity mold, and
• wherein, 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, and
• wherein the blow nozzle further comprises an air vent groove communicating from an inner edge of the second surface to an outer edge of the second surface.