International Business Machines Corporation

Robert A Scranton

David A Thompson

Timothy Joseph Chainer

Thomas K Worthington

Lubomyr Taras Romankiw

Edward John Yarmchuk

John Stewart Best

Richard Greenberg

Suryanarayan G Hegde

John R Reidenbach

Jerry Lee Neubauer

Sol Krongelb

Thomas W Glaser

Robert E Schopp

Mark B Caruso

Avijit Mukherjee

A high speed, small diameter disk storage system having a plurality of disk drive devices utilizing disks with a nominal 65 mm diameter rotated at a speed of approximately 10,000 RPM which can be optimally arranged in a four drive system to match the space geometry of the traditional half-high flexible disk drive used in a personal computer.

High speed, small diameter disk storage system

A device and method for capacitive measurement and control of the fly height of a recording slider. A recording slider is vertically spaced from a rotating disk surface by an 'air bearing'. The disk has a first electrically conductive pattern at its surface. The first pattern has an edge with a length extending, for example, radially. The recording slider has one or more electrically conductive rails extending transverse to the radial pattern on the rotating disk. As the disk rotates, the edge of the pattern on the disk scans across the rail of the slider. By measuring the electrical capacitance between the slider and the pattern on the disk, and by processing the electrical capacitance measurement signal, a vertical spacing signal proportional to the vertical spacing between the disk and the slider can be obtained.

Capacitive measurement and control of the fly height of a recording

A magnetic recording disk is formed on a rigid aluminum substrate coated with a polymeric dielectric layer. A thin film metallic position-indicating track is applied to the upper surface of the dielectric layer. The dielectric material is coated with a magnetic recording medium. A thin film of aluminum forms the patterned capacitive and optically reflective track. The dielectric layer is composed of a very similar material to the matrix material in the magnetic recording medium. The disk can be flexible or floppy and it is not necessary to have the extra dielectric layer in such a case, where the substrate is a dielectric.

Structure to provide optical and capacitive contrast on magnetic

A linear disk actuator is disclosed incorporating a magnetic circuit for reducing stray magnetic fields in the region of the disks and recording heads of a magnetic recording disk system. The moving part of the actuator is provided with a plurality of coils mounted thereon, at least two of which are energized simultaneously and in magnetically opposing relationship to reduce the amplitude of the stray magnetic fields. Movement of the actuator is achieved by both energized coils interacting with a set of alternating poles positioned on the stationary part of the actuator.

Multiple coils for reduction of stray magnetic fields in disk file

An oscillating pneumatodynamic bearing takes the form of a laminated transducer disk cooperating with a flat surface or a tubular transducer cooperating with a rod or an enclosing tube. Such bearings are also known as squeeze bearings. At least one piezoelectric, magnetostrictive or electrostrictive material is laminated with another material to provide oscillation of the transducer portion of the bearing so that the transducer portion is able to fly above a bearing surface on a fluid which is usually ambient air compressed by the mechanical oscillation of the transducer portion at an ultrasonic frequency. The disk or the tube is connected mechanically to supports and to its electrical sources of energy or signals at points along the loci of zero oscillation or minimal oscillation. With a laminated disk, a nodal circle is the locus of zero oscillation. In the case of the tube, a number of parallel strips of reversed polarity transducer material are alternately connected together by an interdigitated electrode design of spacing grooves between an enveloping conductive layer which overlies the piezoelectric layer laminated to a metallic base. Bearings for armatures of linear motor types of actuators for reciprocating magnetic recording heads within magnetic recording disk files can employ a set of disk type bearings or a combination of a tubular bearing with at least one disk type bearing.

Planar and cylindrical oscillating pneumatodynamic bearings

A capacitive variation sensor includes one or more elements providing inductive reactance in the form of thin film coils. This enables a capacitive variation sensor to be integrated on a substrate along with a thin film magnetic read/write head. One element of the capacitive variation sensor is a sensing electrode, and in some embodiments of the invention a dedicated sense electrode can be eliminated by employing the pole tips of the thin film magnetic read/write head as the sense electrode.

Capacitive sensing employing thin film inductors

An improved squeeze bearing apparatus exhibits torsional stiffness or rotational restraint since its rod-like bearing member (22) and its sleeve-like bearing member (28) comprise non-circular perimeters (26,32).

Tubular squeeze bearing apparatus with rotational restraint

Long tube bender element squeeze bearing

A writing implement having special applicability for use as a pressure and acceleration sensitive element for use in a Signature Verification System. The pen structure includes both a writing implement for making a visible record and also includes unique transducer structures for providing both acceleration and pressure data to a remotely located verification system. The pressure sensing element is axially mounted within the pen and produces pressure signals due to axial pressure on the pen tip as an individual writes. The accelerometer structure comprises a hollow tubular piezoelectric member supported at one end and having four circumferentially disposed electrodes on the outer surface thereof, which are appropriately interconnected to produce two orthogonal acceleration component signals A.sub.x and A.sub.y.

Data input pen for Signature Verification

A linear motor adapted for driving a magnetic recording head reciprocably across the surface of a magnetic recording disk in a disk file has its stator located between the disks. The stator includes parallel magnetic yokes composed of plates extending parallel to the disks. At least one of the plates carries an array of regularly spaced and alternating magnetic pole elements, rigidly secured to one yoke with a gap extending between the yokes including the alternating poles providing a space within which the armature reciprocates, from one magnetic polarity to the opposite a plurality of times per reciprocation of the armature. End poles are provided at each end of the array, which are matched to collect the return flux from the adjacent distal pole to reduce fringing flux which emanates towards the disks and the recording heads.

Low mass actuator system for magnetic recording disks with half strength

A method and device for detecting Neel wall segments in a cross-tie memory system involves applying a magnetic field to the Neel wall segments of a given polarity so that these Neel wall segments expand into a transverse domain. The transverse domain is then sensed with a magnetoresistive detector.

Growing community of inventors

South Salem, NY, United States of America

Robert A Scranton