Abstract: A tape cassette allows a complete play through of the tape only once. The cassette comprises a follower arm indicative of the amount of tape on the take-up reel. When a pre-determined amount of tape is wound onto the take-up reel, a lock actuation means is enabled such that when the tape is thereafter rewound a locking arm is displaced into the path of a tooth carried by a locking member on the take-up reel when a pre-determined amount of tape has been wound onto the supply reel. Thereafter, forward feeding of the tape is inhibited because the locking member locks to the remainder of the take-up reel by virtue of a pawl carried by the take-up reel which is urged into a notch in the locking member.

Abstract: In a reel assembly of a tape cassette a one-way clutch mechanism is provi which serves to prevent rotation of the reel in the direction required for the purposes of rewinding a tape thereon. The one-way clutch mechanism includes a slipway channel which extends circumferentially of the axis of rotation of the reel. The reel assembly includes a first clutch member which is designed to be driven by the power output shaft of the winding mechanism and a second member which is designed to be held fast with respect to the cassette. A slipway channel is formed at an interface between the first and second clutch members such that a portion of the channel is formed in the first member and a portion of the channel is formed in the second member. A pawl displacing ring is mounted in the slipway channel so that it bears against the second member and is drivingly connected to the first member by means of a pawl.

Abstract: A tape cassette which has a limited access rewind system includes a one-way coupling arranged to communicate between the spool and the rewind mechanism. The one-way coupling mechanism includes an engagement disc which is mounted in the housing and forms a part of the take-up spool. The one-way coupling device serves to engage automatically to prevent rotation of the spool relative to the engagement member in the unwinding direction and to release automatically to permit free rotation of the spool in the winding direction. A locking mechanism is located in the housing which is operable to secure the engagement member against rotation and thereby prevent rotation of the spool in the take-up direction. The locking mechanism may be released to disengage the engaging member to permit free rotation of the engagement member and spool about the take-up access. The tape cassette also includes a releasable latching mechanism which serves to lock each spool against rotation during shipping and handling.