Voice coil driven positioner for coarse and fine positioning of magnetic head in multi-track tape drive

摘要

A voice coil driven positioner is provided for positioning the magnetic head of a tape drive relative to the tape of a removable tape cartridge. The head positioner includes a low-mass carriage that supports the head on one end and the voice coil on an opposed second end. A low friction guide mechanism guides the carriage along a precision movement path that carries the head across tracks of a supplied multi-track tape and simultaneously carries the voice coil through a flux field generated by a stator. A movable magnet is attached to the carriage and located within the hollow of the voice coil for reciprocating into a hollow passageway of the stator together with reciprocation of the voice coil into another hollow of the stator. A flux detector is attached to the stator and located compactly within the hollow passageway of the stator for detecting the position of the magnet. A programmable lookup table converts measurement signals output by the flux detector into pre-calibrated, head-position indicating signals. A platform is provided on the carriage for mounting an interferometer prism used during calibration.