Patent ID: 6589469
Filing Date: 2003-07-08
Classification: B29C,G11B

Abstract:
A cassette half molding method for molding one of upper and lower halves with an injection mold by injection molding, said upper and lower halves being coupled with each other in a lid alignment manner to form a cassette case for accommodating a pair of take-up hubs around which a magnetic tape is wound, comprising the step of:molding a transparent or semitransparent window portion provided in the upper half of the cassette with said injection mold, molding at least one curved rib to extend from the window portion; and providing a gas vent pin in said injection mold at a position that opposes a ceiling surface of said at least one curved rib for smoothing a flow of molten resin to be introduced in said window portion; wherein said at least one curved rib is a take-up hub position regulating rib.