| 摘要 |
PURPOSE:To enable monolithic molding of a pin within a narrow sphere by reducing a space around the pin which is made necessary in the case where a slide core is used. CONSTITUTION:At the time of resin-molding of a pin like a pivot pin of an aiming device the tip diameter of which having undercut structure is expanded integrally with a body of light means, a mold to mold the pivot pin 8 is constituted of split pin molds 28 constituted of a plurality of split fine pieces which are arranged in the circumferential direction and having a flexibility. The pin 8 is resin-molded by casting resin into a cavity provided within the split fine pieces, the pin 8 is pulled in the pulling-off direction after that, through which mold release of the pin 8 is made possible by deforming the split fine pieces 28d elastically in the outside diametral direction. Mold release can be effected by deforming elastically the split fine pieces by a fine quantity, monolithic molding of the pivot pin 8 becomes possible in an extremely narrow sphere of the body 1 of the light means. |
