Thin-film magnetic head for reading and writing information

Claim 1

A thin-film magnetic head for reading information from and writing information in a track of an associated magnetic recording medium, comprising a magnetically permeable yoke, means coupled thereto for applying a writing current, and a magneto-resistive reading element bridging a gap between two parts of the yoke, said yoke having three limbs: a central limb located in a first plane, and two outer limbs located in a second plane and meeting each other at the area of the central limb while forming a writing/reading gap between the central limb and the outer limbs, an auxiliary gap being present between the outer limbs at the area of the center of the central limb, and that each outer limb, in a place spaced from the writing/reading gap, is separated from the central limb by a gap, said gaps being each bridged by a magneto-resistive element, said magneto-resistive elements cooperating with an associated electric circuit which includes means whereby their signals are subtracted from each other and the difference signal is used to control the position of the head relative to the center of the track.