| 摘要 |
PURPOSE:To remove moldings from deep molding cavities easily with good yields by providing steps to some of knock pin groups for ejection of moldings to press the end parts of the walls of the moldings with the stepped parts to remove the moldings. CONSTITUTION:Many knock pin groups 14, 15 are disposed freely and movably in and out to the 1st mold 16 which molds the entire part of a main wall 5 and standing wal groups (only the standing walls 6, 7 and the standing wall 9 for regulating the loose moving of a tail pulley are shown in the figure) and a mold 17 which molds the outside surface of the wall 5. A gate G for injecting raw material is disposed. Some of the groups 14, 15 are provided with steps 18 in the outside circumferential parts 5 on the forward end side as shown in figure 15 in such a way that the stepped parts 18 abut on the top end faces of the front wall 6. The flat outer side surface 19 of each knock pin 15 on the more foward side than the step 18 forms the molding surface for a part of the inside surface of the wall 6 and the step 18 forms the molding surface in a part of the top end surface of the wall 6. After the molding, the mold 17 is removed to project the knock pins and to remove the moldings easily with good yields. |
