The present invention relates to a magnetic tape cartridge apparatus for use with data processing equipment or similar host and, more particularly, to a cartridge carrier mechanism incorporated in an aggregate type magnetic tape cartridge apparatus for transporting desired one of a number of magnetic tape cartridges to a predetermined position for writing or reading data in or out of the cartridge.
A magnetic tape cartridge apparatus for the above application is disclosed in Japanese Patent Laid-Open Publication (Kokai) No. 235243/1991 by way of example. The apparatus taught in this Kokai includes a cartridge carrier mechanism having a finger cam holder affixed to a push rod and holding rotatable finger cam rollers. The push rod is slidably guided by a finger support. Two fingers are rotatably supported by the finger support at one end thereof and constantly biased toward each other by a finger spring at the intermediate portions thereof. The finger support is driven by a motor. A lock solenoid is mounted on the finger support and prevents the two fingers from closing when a magnetic tape cartridge is to be inserted. A finger frame maintains the two fingers in an open position by pushing out the push rod when the finger support is held in the initial position thereof.
The conventional cartridge carrier mechanism described above has some problems left unsolved, as follows. To begin with, the mechanism for opening and closing the two fingers is located in a region which a magnetic tape cartridge passes when pulled out by the cartridge carrier mechanism. Hence, when a number of magnetic tape cartridges are arranged face-to-face at opposite sides of the tape cartridge apparatus, the cartridge carrier mechanism cannot pull out or insert such cartridges unless it is bodily turned over by an extra mechanism.
Further, the two fingers for nipping the tape cartridge are opened and closed in association with forward/rearward movement caused by a motor. Therefore, when a condition apt to cause the cartridge being transported by the cartridge carrier mechanism to jump out of the fingers occurs, an action for nipping the cartridge by the two fingers has to be performed. The mechanism, therefore, cannot recover from such a condition unless it is moved to the initial position thereof, i.e., a position where the push rod contacts the finger frame.