Patent ID: 7558022

Claim:
A magnetic disk apparatus comprising a rotatable magnetic disk and a magnetic head slider to be able to fly from a surface of the magnetic disk, wherein: the magnetic head slider includes an air bearing surface, by which the magnetic head slider is caused to fly and come near to the rotating surface of the magnetic disk with a predetermined spacing therebetween, a recording and reproducing element to perform at least one of recording on and reproduction from the magnetic disk, and a heating device to adjust a distance between the recording and reproducing element and the surface of the magnetic disk through an air pressure; the air bearing surface is formed by a plurality of substantially parallel surfaces, the plurality of surfaces include an element mount surface, which comes nearest to the magnetic disk at the time of operation and on which the recording and reproducing element is mounted, and a groove surface having two or more kinds of predetermined depths, respectively, from the element mount surface, and that position, in which the heating device is projected on the air bearing surface, is disposed within the element mount surface, and separated from that region, in which the recording and reproducing element is mounted, with a groove therebetween; and the heating device is mounted such that heating thereof causes a part of the air bearing surface to expand and project to increase a distance between the recording and reproducing element and the surface of the magnetic disk.