| 摘要 |
PROBLEM TO BE SOLVED: To improve deterioration of a surface deflection of an optical disk substrate in the case of continuously molding without holding fine powder by a substrate thrusting members by forming an air gap at a rear end of the member in the state that the member is retreated. SOLUTION: A substrate thrusting member 10 is retreated by a pressure from an air circuit 13 during injection molding, but a tapered part 18 is provided on an outer periphery of its rear end, and at the time of retreating, an air gap 19 is existed. At the time of thrusting the substrate, the air of the circuit 13 is stopped, and the member 10 is forwarded by the air from an air circuit 12. Thereafter, the air of the circuit 12 is stopped, the member 10 is retreated by the air from the circuit 13, and next molding is executed. Thus, since the gap 19 is formed, fine powder generated by repeated driving of the member 10 and a gate cutting punch 9 is stored in the gap 19 and removed. |
