Patent ID: 6883739

Claim:
A tape threading mechanism comprising: a take-up reel for taking up a magnetic tape within a tape cartridge; a leader block to be fixed to a tip of said magnetic tape; a threading arm having a threading pin movable in an arcuate trajectory for moving said leader block from said tape cartridge to said take-up reel; and a guide groove, provided in said take-up reel, for guiding said leader block toward a take-up center from an intrusion port in the vicinity of an outer periphery of said take-up reel, wherein on a side wall of said guide groove, outside the arcuate trajectory of said threading pin, a first guide surface is provided, wherein a second guide surface is provided on the other side wall of said guide groove, said second guide surface having a curved surface portion in the vicinity of the outer periphery of said take-up reel, wherein said first guide surface includes first and second parts, wherein said first part of said first guide surface is linear and is provided in the vicinity of said outer periphery of said take-up reel, a surface of said first part is parallel with a center line of said guide groove, and said second part is a curved surface in conformity with the arcuate trajectory of said threading pin, and wherein said guide groove is arranged so that when introducing said leader block into said intrusion port, a tip of said leader block abuts against said first part of said first guide surface, and a side surface of said leader block abuts against said curved surface portion of said second guide surface.