| 摘要 |
PURPOSE:To enable to perfectly prevent flowing out of burrs to a metallic outer peripheral surface of a molded work and to enable reducing of the number of processes through elimination of an operation to grind the work after molding, by a method wherein a reinforcing ring is held between the nip formed by a center core and a bottom force to manage the size of the width of the reinforcing ring. CONSTITUTION:The reinforcing ring 2 of an oil seal 1 is placed on a bottom force 6. A flange part 22 of the reinforcing ring 2 makes contact with a slotted stage part 61 of the bottom force 6. Then, through pressing down of a center core 5, the projection 51 of the center core 5 is brought into contact with the upper end of the reinforcing ring 2. A pot part 52 of the center core is filled with a material 3 in a way to form it into an annular shape as much as possible, and a mold is closed by depressing down a top force 4 with the aid of a press pressure. The material 3 flows and is injected in a cavity for filling. The reinforcing ring 2 may be prevented from surfacing through the force of an injection pressure produced in case the rubber material is injected into the cavity, and a gap, through which the injected rubber material flows out as burrs, is prevented from occurring between the reinforcing ring 2 and the forces 6 and 7. |
