Disk drive head accessing mechanism

Claim 1

A disk drive, comprising: a planar disk which spins about a fixed-position axis, and carries a multiplicity of concentric data tracks; a magnetic head which moves generally along one disk radius, as the head is selectively positioned to transduce one of the disk's data tracks, said head movement being along an arc which crosses said one radius at least once; a head carriage upon which said head is mounted; a fixed-length, pivoting link having one end pivotally mounted on said disk drive, and the other end pivotally supporting one portion of said head carriage; a rotatable pulley means drivingly engaging a spaced cam means portion of said head carriage, and operable to cause said head carriage to move generally along said radius and thereby rotate about the point of its attachment to said other end of said pivoted link as said pulley means rotates, to thereby radially move said head to a selected track position, and to concomitantly produce azimuth rotation of said head about an axis parallel to the disk's spin axis, thereby producing generally the same azimuth attitude of said head at each of said data tracks; and movement means operable to produce concomitant rotation of said pulley means and generally radial movement of said head carriage.