Abstract: A compact and simple lapping apparatus in which, even if projections and depressions are formed in the circumferential direction on the top surface of a lapping plate, a workpiece and a bar are hard to damage and the polished surface of the workpiece is kept in good condition. This apparatus is provided with at least one lapping jig in which a workpiece is placed on the rotating top surface of the lapping plate. Further, a lapping head adapted to be able to rotate only in a direction on the lapping plate is attached to this lapping jig. This lapping head is equipped with a workpiece and at least two dummy work materials (or stock) so that these dummy works compose (as-polished) surfaces, which should be polished, together with the workpiece. Moreover, a device for detecting the remaining part of the workpiece to be lapped is provided on the workpiece.

Abstract: A magnetic head which can fly over a surface of a magnetic recording medium comprises a main body fitted into a supporting arm, rail surfaces formed in the main body to serve pneumatic bearings, and projections formed on the rail surfaces and having surfaces opposing a magnetic recording medium. The projections have larger surface roughness than that of the magnetic recording medium, whereby wear-out rate of the projections provided on the magnetic head can be reduced and also the projections can be firmly brought into contact with the surface of the magnetic recording medium.

Abstract: A method for manufacturing a thin film magnetic head slider having a media opposing surface which is adapted to be opposed to a recording medium, includes the steps of forming on a sacrificial layer, on a substrate, in such a manner that the sacrificial layer has a surface including steps for forming the media opposing surface having at least one rail, providing a slider material on the surface of the sacrificial layer, and removing the sacrificial layer and the substrate from the slider. A tracking mechanism or loading/unloading mechanism can be provided on the slider. An electrostatic actuator suitable for driving such a mechanism includes a stationary section having a plurality of teeth parallel to each other, a movable section having a plurality of teeth parallel to the teeth of the stationary section, a support spring for supporting the movable section so that the movable section can be moved with respect to the stationary section in the tooth width direction.

Abstract: An acceleration sensor is provided which has a plurality of piezoelectric elements having polarization directions which are different from the direction of the acceleration to be detected and which have electrodes provided on both sides are mounted to a substrate, or a singly formed piezoelectric element having a plurality of polarizations with independent electrodes provided for each region is mounted to a substrate, a series electrical connection being made between the substrate side electrodes and the free end electrodes of the piezoelectric elements, the electrodes between which the piezoelectric element are series connected being led out to two electrodes provided on the substrate, and a weight being mounted over and such a manner as to straddle the plurality of piezoelectric elements or singly formed piezoelectric element. When an acceleration acts on this acceleration sensor, the force of inertia of the weight applies a stress to each piezoelectric element, causing the generation of a voltage.

Abstract: In a device which is adapted to write and read an information on and from a recording disk through a head and includes a head actuator for moving the head in a radial direction of the recording disk so as to position the head at a desired recording track on the recording disk, a mechanism for minute movement of a head provided at a part of the head actuator is capable of moving the head a very small distance independently of an operation of the head actuator. This mechanism for minute movement of a head is provided with expansion regions which are arranged symmetrically with respect to a center line of the head actuator and are separated by a clearance. Expansion members which are fixed on both or either of front and rear surfaces of the expansion regions, cause the expansion regions to expand or contract by the deformation thereof produced according to application of the power.

Abstract: A magnetic memory device comprises: a vertically magnetic recording medium; a probe formed of an electrically conductive as well as soft-magnetic material, a pointed end of the probe faces the magnetically recording medium across a gap; a magnetic flux detecting element for detecting a magnetic flux caught by the probe, where the magnetic flux is from a data recorded on the magnetically recording medium; a vertical controller for keeping the gap constant by the use of a tunnel current flowing via said gap into the probe while a voltage is applied across the gap; and a scan mechanism for scanning the probe along the magnetically recording medium. The magnetic memory device may further comprises an exciting coil for magnetizing the probe so as to write a data in the magnetically recording medium. The probe may be recessed from the scanning position when the probe is not in operation.

Abstract: A magnetic disk storage apparatus comprising a rotary actuator which prevents head positioning error resulting from vibration and impact. Since head positioning error is generated when the enclosure makes rotating movement due to translational vibration input due to vibration, a vibration proof mechanism consisting of a plurality of vibration proof supporting members are provided between the enclosure and frame. The plural vibration proof supporting members are disposed so that the linear moment around the gravity center of the enclosure is balanced against translational external force applied to the enclosure.

Abstract: A rotating support apparatus in a disk storage device is provided with a stationary shaft, ball bearings rotatably fitted on the stationary shaft, a rotatable member rotatably supported by and on the ball bearings, and buffer rings superimposed between the associated ball bearings and the rotatable member to absorb a thermal deformation of the rotatable member due to a change in a temperature. The buffer rings have a same coefficient of linear expansion as that of the material of which the rotatable member is made, and each of the buffer rings is in contact, at two points of the outer inner surfaces thereof, with the rotatable member or outer races of the ball bearings, and at one point of the inner or outer surface thereof, with the associated ball bearing or the inner surface of the hub, respectively.

Abstract: A rotary actuator for positioning magnetic heads in a disk drive, comprising a stator assembly and a rotor assembly. An arm assembly having magnetic heads are fixed to the rotor assembly, which rotates back and forth within a limited angle range around a fixed axis of the rotary actuator due to the forces between plural magnets and driving current which flows though flat coils. Two flat coils are aranged on an arcuate inner surface of the stator such that two adjacent vertical parallel portions thereof closely contact with each other. Two flat coils have an electrical connection with a driving source that the currents through the two adjacently parallel portions flow in the same direction. Three permanent magnets are disposed on the rotor surface, the central magnet having a greater lateral width than that of other two side magnets, and a polarity of the central magnet is opposite to that of other magnets.