| 摘要 |
PURPOSE:To prevent spreading of resilient rubber material to the sliding face side of a sliding ring when molding, by providing annular recess in the surface of a mold and storing the resilient rubber material in said recesses. CONSTITUTION:Mold faces 100a, 100b of a mold 100 are tapered and a plural rows of annular recesses 13, 14 are made in step in said tapered face. With such arrangement, when vulcanized resilient rubber material is pressurized and molded through thermosetting, excessive material 12 flows in positively and sequentially in step into the annular recesses 13, 14, thereby the resilient rubber material does not spread to the sliding face 3a side of a sliding ring 3. |
