INJECTION MOLDING MOLD FOR AN INJECTION MOLDING UNIT OF AN INJECTION STRETCH BLOW MOLDING MACHINE, METHOD FOR MOLDING A PREFORM, AND A METHOD FOR MOLDING A CONTAINER

The invention relates to an injection molding mold formed in an injection molding unit of an injection stretch blow molding machine including: a rotating plate unit having a rotating plate and stopping whenever the rotating plate rotates at a constant rotation angle and ascending or decending; and an injection molding unit, that is disposed under the rotating plate unit.According to the invention, the following is provided_ (i) the injection molding mold includesa cavity mold,a lip mold for molding an outer peripheral surface of a preform mouth portion, the lip mold disposed on a bottom surface of the rotating plate and configured to descend toward the cavity mold together with the rotating plate unit when it is situated in a position corresponding to the injection molding unit by rotation of the rotating plate, anda core mold that ascends and descends insertably into the cavity mold through the cavity mold and the lip mold to form_ a preform formation space enclosed by the lip mold, the cavity mold, and the core mold,(ii) the preform formation space is formed froma preform mouth portion forming portion,a preform body forming portion that is continuous with the preform mouth portion forming portion and has a gap width uniform and wider than a gap width of the preform mouth portion forming portion, anda preform bottom forming portion that is continuous with the preform body forming portion and has a lower end located on a side of a gate,(iii) the core mold includesa preform mouth portion inner surface forming portion corresponding to the preform mouth portion forming portion,a preform body inner surface forming portion corresponding to the preform body forming portion,a preform bottom inner surface forming portion corresponding to the preform bottom forming portion, anda diameter enlarging portion in which a diameter of the core mold is gradually enlarged from the preform body inner surface forming portion to the preform mouth portion inner surface forming portion,(iv) in the diameter enlarging portion, a core mold outer peripheral surface is tapered so as to be inclined outward relative to a position of an upper extension line along the core mold outer peripheral surface in the preform body inner surface forming portion,(v) the core mold outer peripheral surface in the diameter enlarging portion is continuous between the preform body inner surface forming portion and a portion of the preform mouth portion inner surface forming portion facing the lip mold,