Patent ID: 6680818
Filing Date: 2004-01-20
Classification: G11B

Abstract:
A magnetic tape cartridge, for rotatably housing within a cartridge case a single reel having magnetic tape wound thereon, comprising reel-rotation restraining means for allowing rotation of said reel when being used and restricting said rotation when not being used; whereinsaid reel-rotation restraining means has a restraining member for restricting rotation of said reel by moving toward or away from said reel, an urging member for urging said restraining member in a restraining direction, and a releasing member for moving said restraining member in a releasing direction, by rotating integrally with said reel and moving according to a chucking operation of drive-side rotation drive means; said reel is provided with a reel gear which meshes with a driving gear of said drive-side rotation drive means, and a pushing-up portion formed in part of said releasing member is provided so that a distal end thereof can abut said driving gear through a through hole provided in said reel gear; and said through hole is bored between tooth edges of said reel gear, wherein the distal end of the releasing member is configured to be engaged by at least one tooth of said driving gear, and a recess engagable with a tooth edge of said driving gear is formed in a distal end surface of said releasing member which abuts said driving gear.