| 摘要 |
PROBLEM TO BE SOLVED: To prevent molding defect such as bubble marks and weld from being generated on the outer surface of an upper or lower cassette half by arranging a gate connection part where a gate is connected at the time of molding near a part where a reel-positioning rib is provided on a flat plate. SOLUTION: A gate connection part 14 is arranged immediately below a reel positioning rib 13a of an upper cassette half 11. When the upper cassette half 11 is to be molded, melted resin injected from a nozzle flows into a cavity for the reel positioning rib 13a to fill it, and then flows into a cavity for flat plate. Therefore, since gas in the cavity for the reel positioning rib 13a is degassed speedily via the cavity for flat plate, a gas vent, and the like, no bubbles are entrapped into the cavity for the reel positioning rib 13a, and the melted resin smoothly flows into the cavity without incurring a great pressure loss.
|
