Preform manufacturing device, manufacturing method, and mold for cooling

A preform manufacturing method comprising:

• injecting and forming a bottomed cylindrical resin preform using an injection mold as injection molding;
• cooling the preform manufactured in the injection molding as post-cooling;
• and
• taking-out the preform cooled in the post-cooling to the outside of the apparatus, wherein
• in the post-cooling,
• a first mold which accommodates the preform inside and which contacts the outer surface of the preform;
• and
• a second mold which is inserted into the preform and which is provided with at least a cooling rod having an internal flow path for compressed air and a tip piece which is attached to a tip side of the cooling rod are used,
• the tip piece has a shape corresponding to a bottom of the preform and includes a mold surface that receives the bottom, and an opening formed on a base end side of the mold surface and communicating with the flow path of the compressed air, and
• in the post-cooling, the bottom of the preform is cooled while pressing the bottom of the preform against the first mold with the mold surface of the tip piece, and a body portion of the preform is cooled while pressing the body portion against the first mold with the compressed air passing through the opening.

A cooling mold used in a post-cooling unit of a preform manufacturing apparatus, the apparatus including an injection molding unit configured to inject and mold a bottomed cylindrical resin preform using an injection mold;

• the post-cooling unit configured to cool the preform manufactured in the injection molding unit;
• and a taking-out unit configured to take-out out the preform cooled in the post-cooling unit to the outside of the apparatus, the cooling mold comprising:
• a first mold which accommodates the preform inside and which contacts the outer surface of the preform;
• and
• a second mold which is inserted into the preform and which is provided with at least a cooling rod having an internal flow path for compressed air and a tip piece which is attached to a tip side of the cooling rod, wherein
• the tip piece has a shape corresponding to a bottom of the preform and includes a mold surface that receives the bottom, and an opening formed on a base end side of the mold surface and communicating with the flow path of the compressed air.