Magnetic Tape Cassettes and Tape Reels and Metal Molds Making the Same

摘要

The present invention relates to a tape reel, wherein the thin flange portion is formed by reducing the thickness of each of the front and rear flange surfaces of the tape reel, and the scraped thickness portion having a thickness thicker than the thickness of the thin flange portion is located at a plurality of positions around the flange portion. Is formed. When the tape reel is formed using a molded metal mold, a pin is inserted into the molded metal mold at a position corresponding to the last resin filling position in the thin flange portion, and air and gas in the cavity are formed between the molded metal mold and the pin. Is discharged through the space. Thus, it is possible to prevent the occurrence of short molding and joining lines in the thin portion of the tape reel formed in this way, it is possible to prevent the shaking on the reel flange surface.;In addition, according to the present invention, the front and rear portions of the upper and lower flanges are formed in a thin flange portion by uniformly reducing the thickness of each of the front and rear portions thereof except for the outer circumference portion thereof, and the radial tape position limiting ribs 7 are upper and lower portions. It is formed on the tape contact flange surface of the flange. Thus, the flange can be prevented from bending even though its thickness is reduced. The weight of the tape reel can be reduced and the material can be reduced accordingly. In addition, the tape reel of the present invention can obtain the same operation as that of the conventional tape reel.