Shoes midsole forming apparatus and shoes midsole manufactured using the same

A midsole molding apparatus comprising:

• an upper mold (100);
• a lower mold (200);
• a plurality of inner spaces (120 and 220) formed by the upper mold (100) and the lower mold (200) in a closed state, in which a shaft is positioned in the plurality of inner spaces and a through hole is perforated in a lateral direction of a midsole by the shaft when the midsole is formed through a foaming injection by injecting a raw material into the plurality of inner spaces;
• a shaft mold (300) provided in the lower mold (200), the shaft mold (300) includes a platform (360) for moving up and down by a restoring element when the upper and lower molds (100 and 200) are closed and opened, and a plurality of shafts (320) form a pair of midsoles at left and right of the platform and form the through hole perforated in a lateral direction of the midsole;
• a receiving groove (160) formed in the upper mold for receiving the platform (360), the shaft mold (300) is provided between the upper mold (100) and the lower mold (200) when the upper and lower molds are in a closed state;
• and
• a plurality of extension portions (340) formed in the shafts (320) such that a length of the shafts (320) exceeds a boundary of the plurality of inner spaces (120 and 220) of the upper and lower molds (100 and 200) where the midsole is molded,
• wherein the upper and lower molds (100 and 200) are formed with press grooves (140 and 240) to fixedly surround only the plurality of extension portions (340) of the shaft mold (300) when the upper and lower molds (100 and 200) are in a closed state, and
• wherein the shafts (320), which extend leftward and rightward from the platform of the shaft mold having the plurality of extension portions (340), include a hollow structure with an elastic property to enhance adhesion strength against the press grooves, so an injection foaming process is performed without generating parting lines and burs on an inner surface of the through hole which is perforated in the lateral direction.