Magnetic tape drive with integral multiple-cassette removable magazine

Abstract

A number of data storage cassettes are held in a removeable magazine that forms part of a tape drive by which the magnetic tapes are recorded or played. The magazine holds two parallel vertically-displaced decks of cassettes that are moved under positive driving force along a rectangular pathway formed by the two decks. From a pick-up position in the magazine, a cassette is automatically extracted by a robotic arm and placed in the tape platform for reading or writing by a conventional tape drive mechanism. When the use of the cassette is finished and it is ejected by the tape drive, a sensor activates the robotic arm to return the cassette to the pick-up position. Each deck has one unoccupied cassette space. If during the sequence of operations, the cassettes on the lower deck are moved by the width of one cassette in one direction, the cassettes on the upper deck are moved the same distance in the opposite direction. This movement results in a vacant position at the end of the upper deck farthest away from the pick-up position. The cassette in the pick-up position is either removed and loaded into the tape deck or the cycle is continued. Movement of the cassette is produced by reciprocating drivers along the sides of the magazines. The cassettes are moved in only one direction by the reciprocating drivers and are locked to prevent movement in the opposite direction. Motions of the cassette handling mechanisms are limited by mechanical stops that trigger an electronic circuit to interrupt the driving power eliminating the need for sensitive position switches. Slip clutches prevent mechanical damage from the mechanical stops. The removable magazine does not include any electric motor drives and is automatically disengaged from the cassette driving mechanism by its removal, thus permitting economical use of multiple magazines.