Abstract: A gasket for a disc drive system having a recording media within a sealed housing having top and bottom casing members, a read/write head for transferring information between the recording media and an external system and a head positioner assembly for locating the head relative to the recording media, the improvement comprising a gasket for sealing a connection between the top and bottom casing members. The gasket includes a liner sheet for lateral stability during thermo cycling and opposing layers of a foam material flame bonded to the liner sheet. The foam material is polypropylene.

Abstract: A flexible magnetic data storage disk with a ferromagnetic surveillance ring-shaped marker integrally bonded to the disk substrate around the central aperture. A series of slits are formed in the disk substrate under the marker to serve as "tear initiators" if a user attempts to remove the surveillance marker thus rendering the disk unusable and thereby protecting the data on the disk from unauthorized removal from a secure area.

Abstract: A magnetic head without an erase head, which includes a substantially U-shaped magnetic core with opposed end faces of a pair of legs forming a gap; and a magnetic material attached to one of the end faces to form a write read head with the other end face to write and read data from a recording medium. The magnetic material has a saturated flux density lower than that of the magnetic core. A read track width made by the magnetic material and the other end face is smaller than a write track width made by the opposed end faces.

Abstract: A floating type magnetic head assembly comprises: a magnetic head constituting a first slider; a second slider in which the first slider is so supported as to be movable in straight line only in a direction perpendicular to a magnetic recording disc and as to project outwardly beyond the second slider toward the recording disc; a cantilever arm formed from a thin elastic plate and supporting at its distal end the second slider over the recording medium, the second slider being thus supported in a freely rotatable state about a fulcrum in a form of a projection for applying pressing force from the arm on the second slider on the side thereof oppositely remote from the recording disc; and force exerting means for exerting a pressing force on the first slider by way of its supporting means.

Abstract: The thin film magnet head is to be guided over a recording medium to be magnetized perpendicularly, in which flux changes are to be registered along a track with a predetermined record wavelength and flux change density. The magnet head contains a flux-carrying, ring head-like guiding element with two magnet legs which constitute magnet poles which are arranged one behind the other and separated by a gap of predetermined width and having predetermined extents in the movement direction. With this magnet head the expanse for signal processing in a write/read channel is to be reduced. The magnet head fulfills this end by at least approximately satisfying the following relation:.lambda.*=g+max(A.sub.1, A.sub.2).lambda.* being the record wavelength which results for the value D.sub.p of the flux change density at which the read voltage of the magnet head is maximum; g, the width of the gap; and max(A.sub.1, A.sub.2) the greater value of the two extents (A.sub.1, A.sub.2) of the magnet poles.

Abstract: A thin film magnetic head for performing recording and readout operations to a magnetic recording medium and a method of manufacturing the head. The magnetic head .[.comprises.]. .Iadd.includes .Iaddend.a substrate, a first magnetic layer formed on the substrate, a conductor coil on the first layer and a second magnetic layer formed on the conductor coil and the first magnetic layer. The second magnetic layer is imparted with a greater thickness than the first magnetic layer to thereby strengthen the magnetic field for recording and reducing the peak shift making appearance in readout operation due to interference between successively read-out waveforms. The thin film magnetic head exhibits an improved reproduction characteristic which permits reproduction with high fidelity the magnetized locations recorded on the medium with high recording density which assures an improved recording characteristic. .Iadd.