| 摘要 |
In order to produce a cassette, such as tape cassette, disc cassette or the like, the following steps are taken. First, fixed and movable dies are prepared which are unitable to define therewithin a shaped cavity. The movable die has at its inner surface a retaining ridge which includes a first portion immediately projected from the inner surface and a second portion immediately projected from the first portion. The second portion has side walls at least one of which has a laterally extending projection at the position remote from the first portion. Second, the fixed and movable dies are coupled to define the shaped cavity therewithin. Third, a plastic material is injected into the shaped cavity in such a manner that the retaining ridge is immersed in the injected plastic material. Fourth, the fixed and movable dies are uncoupled and a cured molded article of the plastic material thus produced is released from the movable die. Due to the unique configuration of the retaining ridge, undesirable burrs which are inevitably produced on the molded article are entirely positioned in a groove which is formed in the article by the retaining ridge.
|
