International Business Machines Corporation

Hitachi Global Storage Technologies Netherlands B.v.

Friedrich Fleischmann

Andreas Heinrich Dietzel

Ruediger Friedrich Berger

Frank Krause

A suspension arm ( ) of a disk storage device has an elastic portion ( ) with thickness d and a rigid portion ( ) with thickness d . At the free end of the suspension arm, a slider ( ) is mounted on the suspension arm. The bottom surface of the slider has a distance FH to a top surface of a hard disk ( ). The suspension arm particularly comprises a heating element ( ) disposed on the suspension arm. An electric current I flowing through electrical supply wires ( ) causes the temperature of the suspension arm locally to rise and therefore its spring constant to decrease. Together with the force F resulting from the air cushion effect of the slider a new equilibrium flying height FH is stabilized.

Method and apparatus for dynamically controlling the flying behavior and height of a read/write head in a storage device by manipulating the spring constant of the suspension

A method and apparatus for recording and storing information on and reproducing information from a storage medium is described, wherein the active storage medium forms part of the write/read signal path.

Method and apparatus for recording, storing and reproducing information

Briefly, in a preferred embodiment, the present invention comprises a suspension having a structured surface hardening. This surface hardening may be comprised of thin film stripes of material such as nitrides, carbides, and adamantine carbon. The hardened layer has a thickness in the range of 10-100 nm.

Micromechanical cantilever suspension system

A process permits the determination of multi-dimensional distribution of magnetic fields. The process uses a magneto-resistive sensor as a physical measuring device. The measuring device is coupled with a method for algebraic reconstruction so that sectional images of the field distribution are calculated from individual measurements of the magneto-resistive effect using the algebraic reconstruction.

Method and device for measuring the distribution of magnetic fields

A magnetic disk tester which also incorporates a sensor such as an AFM or MFM is described. The device is able directly and quickly to detect and characterize sub-micrometric defects on the surface of magnetic disks. A process for finding and characterizing defects on a magnetic disk according to the invention comprises the steps of rotating the magnetic disk using a spindle motor; writing data on the magnetic disk at selected positions; finding a position on the magnetic disk having a defect which produces an error when reading the data from the magnetic disk; determining coordinates of the defect referenced from an index on the disk; stopping the spindle motor; positioning a sensing device such as an AFM or MFM head over the defect; and sensing characteristics of the defect which aid in determining a cause of the defect. A magnetic disk examination device embodying the invention comprises a spindle rotably connected to a spindle motor; a magnetic read/write head mounted on an actuator; a magnetic read/write tester for writing then reading magnetic data on the magnetic disk while rotating to find a position on the magnetic disk which produces read errors; a sensor mounted on an actuator which can be a second actuator or the same as the one for the read/write head; a positioning system which places the sensor at the position of the error while the magnetic disk is stationary; and a data acquisition system which gathers data using the sensor.

Growing community of inventors

Erlangen, Germany

Friedrich Fleischmann