Patent attributes
A single reel tape cartridge capable of achieving high-speed read/write access to tapes at high density by enhancing the molding accuracy of lower flange and eliminating inclination and waviness of flange walls is provided. A reel incorporated in a main case is composed of an upper flange, a lower flange, and a boss which is integrally plastic-molded with the lower flange for taking up a magnetic tape. An exit port for allowing an operating nail of an unlock tool to get in and out is open on the bottom wall of the boss. The lower flange is molded in the state that a bridging piece extending along radial direction of the lower flange is formed in the exit port, so that resin flow to the flange wall radially outside the exit port is promoted. The bridging piece is removed after the lower flange is molded.
