| 摘要 |
PURPOSE: To obtain a good blending property of a resin, and to improve the strength, the durability, and the handling efficiency of an oil seal ring, by forming it with a synthetic resin which can be injection molded, and providing a gate to be the starting point of the flow of a molten resin in the molding time, at either one side end. CONSTITUTION: An oil seal ring 1 is formed by providing a gate 3 to pour a molten resin P to the cavity 2 of an injection molding die near one side end of the cavity 2, and pouring the molten resin P to the cavity 2 from the gate 3. As a result, the majority of the molten resin P poured to the cavity 2 from the gate 3 flows to the other side end 2b. Consequently, the blending property of the resin is improved, so as to facilitate the strength of the oil seal ring 1. |
