52 巻 (2011) 608 号 p. 1012-1016
A method of the determining the blocker shape of a type of park gear for automatic transmission was developed. In the method, four different basic shapes were first defined on the basis of the experience and knowledge of experts. Then, four parameters concerning the underfilling of the material into dies and die wear were evaluated by the finite element method. The proposed method was applied to the design of the blocker shape of an actual closed die forging of on idler and a gear part. The optimal blocker shape was successfully determined with fairly short calculation times. The optimal blocker shape of another single park gear was also successfully obtained by the proposed method.