| 摘要 |
PROBLEM TO BE SOLVED: To enable high speed production and to improve product precision by a method in which a coil spring which keeps a mold closed by making a cope contact a drag in a prescribed range before and behind a lower dead center is provided, and while the mold being closed, pressurized air is introduced into the mold simultaneously from the cope and drag sides to pressurize the inside. SOLUTION: When a cope 2 is brought down, the cope 2 is made to contact a drag 3 over a prescribed range before and behind a lower dead center to keep a mold closed for a prescribed time. A coil spring 6 which extends/ contracts before and behind the lower dead center is provided, while the mold being closed, pressurized air is introduced simultaneously into the mold from the air passages 9, 13 of the cope 2 and the drag 3. In this way, a thermoplastic resin sheet 4 is pressed uniformly from above and below to make a flat surface. Especially, the sheet 4 is pressed closely to a projected frame body 11 to be molded into a correct shape corresponding to the peripheral shape of the frame body 11. Besides, it is not necessary for a crank to be stopped temporarily to enable high speed production of a carrier tape by continuous operation. |
