| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To smoothly perform production of the resin molded article by surely leaving the molded article remained in a mold on a desired side in a step for opening the mold when manufacturing a resin gear or a resin pulley or the like through injection molding. <P>SOLUTION: The resin molded article is integrally molded with a shaft as the rotating shaft of the annular outer periphery and a web 14 by injection molding of resin. The rib 11 to be the outer periphery is formed thicker in the thickness in the rotating shaft direction than that of the web 14, and a ring-shaped protrusion 15 as an undercut in demolding on the inner peripheral surface of a rim 11 is provided on the opposite side to the side where the gate trace 16 of the molded article exists. The ring-shaped protrusion can be provided on the outer peripheral surface of the shaft or the side surface of the rib and can be a spiral protrusion. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
