Abstract: A disk recording and/or reproduction device subject to acceleration forces in which the transducer track following function is augmented by an acceleration responsive transducer positioning control. The acceleration response is calibrated as a function of the position error of the transducer with respect to the center of the track being followed.

Abstract: A head suspension assembly for a disk drive has elongated members, in the form of flat strips of stainless steel, which have distal ends welded to the mounting ends of stainless steel load beams with the load beam and the stainless steel strips in alignment. Magnetic heads are mounted in corresponding positions on the distal ends of the load beams. The stainless steel strips are welded together at their distal ends with the load beams aligned with one another and the magnetic heads on the distal ends of the load beams facing in opposite directions. The stainless steel strips are of the same thickness as the reinforcing plates or swage plates which they replace. The load beams are spaced apart by the combined thickness of the stainless steel strips. An arm of an actuator is positioned between and secured to the mounting ends of the stainless steel strips, providing an A-frame type of structure which is light in weight, dimensionally stable and rigid.

Abstract: Image development and transfer apparatus for use in electrophotographic color printers and including a photoconductor, such as either a photoconductive drum or belt, which is spaced from sources of liquid color toners. An intermediate transport film is driven around a section of the photoconductor surface and between this surface and the sources of liquid color toners. Thus, the latent image developed on the surface of the photoconductor is transferred from the surface of the photoconductor to the outer surface of the intermediate transport film where the composite color image is developed. Then, this composite color image is transferred directly onto a print receiving media. Consequently, the photoconductor is not exposed to heat or carrier fluids during the image transfer and development process. This novel feature not only improves overall print quality on the printed media, but additionally extends the useful lifetime of the photoconductor.

Abstract: A disk drive system employs uniform size data blocks, with each disk having a sectorized track format and each sector of a track including at least one servo burst. Data blocks exhibit a constant data density across a plurality of disk tracks of differing radii. The system comprises read/write apparatus for accessing both servo signals and data signals in each disk sector. A servo system is responsive to servo signals fed from the read/write apparatus to generate a synchronizing signal. A data sector pulse generation circuit is responsive to the synchronizing signal to generate and pass to the read/write apparatus, a data sector pulse for each block of data commencing in a sector. That data sector pulse enables operation of the read/write apparatus upon the data block. A control circuit enables the delay of generation of a next data sector pulse when any block of data is split by a servo burst. The delay period is the duration of the servo burst and the portion of the data block that follows the servo burst.

Abstract: A thermal ink jet print device having a phase change material, a solid or fluid, disposed in heat exchange proximity to the thermal ink jet printhead to absorb printhead heat energy by changing physical state at a printhead temperature below that at which unacceptable printing takes place and at a rate commensurate with the rate of heat energy input.

Abstract: A memory system having a moving memory recording media. A sector in each track on the media includes recordings defining a synchronizing field and a start of data field. Selected bit signals of bit signals derived from the recordings are simultaneously combined in a plurality of differing bit signal combinations. The simultaneously validity of all of the bit signals in each of a predetermined number of the differing bit signal combinations, which predetermined number is less than the plurality of bit signal combinations, provides fault tolerant detection of the start of data field.

Abstract: A rotary accelerometer has capacitively coupled rotary and fixed thin film electrodes fixed to a substrate. The rotary electrode is angularly flexible and has a central hub secured to the substrate and spoke electrodes radially extending from the hub. Elongated electrodes are fixed to the substrate in circumferential positions on each side of each spoke electrode and in the same plane as the spoke electrodes. The rotary electrode, having a mass and being angularly flexible, responds to angular acceleration to differentially change the gaps between its spoke electrodes and the adjacent fixed electrodes. The fixed electrodes are energized with rectangular wave voltages of opposite phase. The sum of these voltages in the spoke electrodes is a function of the difference in the gaps which, in turn, is a function of the angular inertia of the rotary electrode.

Abstract: A sector in each track of a moving memory recording media includes recordings defining a synchronizing field and a start of data field. Selected bit signals of bit signals derived from recordings are simultaneously combined in a plurality of differing bit signal combinations. The simultaneous existence or validity of all of the bit signals in each of a predetermined number of differing bit signal combinations, which predetermined number is less than the plurality of bit signal combinations, provides fault tolerant detection of start of data field.

Abstract: Resistance to shock forces having components acting parallel to the spindle axis of a disk stack is provided by spacing the surface of a circumferential flange of a disk spacer a distance above the surface of a disk in the disk stack which is sufficient to clear the magnetic head and flexure assembly therebeneath during movement thereof during flight to and from a parked position between the confronting surfaces of the circumferential flange and the disk.

Abstract: A disk type of magnetic recording device having a support plate in which parts, normally separately fabricated and separately attached to the support in assembling the device, are simultaneously outsert molded on the support by indexing clamping the support, which has openings therethrough where parts are to be secured, between upper and lower sections of a mold, each mold section having cavities at such openings defining part configurations and/or attach flanges, and thereafter outsert molding the parts by injecting a fluid plastic material such as polycarbonate, into the mold, completely filling the cavities.

Abstract: Closer spacing of the disks in a disk stack of a disk drive is achieved by joining together the reinforcing plates, sometimes called swage plates, of pairs of load beams of the actuator arm structure to form a transducer suspension assembly of an integrated pair of load beams, each load beam having a distal end flexibly mounting a transducer The transducer of each integrated load beam pair are aligned with each other and face in opposite directions. A load beam extension at the load beam end opposite the distal end of each extends beyond the reinforcing plate. These load beam extensions in each transducer suspension assembly are spaced apart by the thickness of the two reinforcing plates and span the thickness of an actuator arm of the actuator arm structure. The load beam extensions are joined to the opposite faces of the actuator arm. The transducers fit between and confront the surfaces of adjacent axially spaced disks in the disk stack.

Abstract: In a magnetic disk memory drive, inertia in the magnetic head positioning system is reduced by providing a light weight, integrated, magnetic head suspension assembly fabricated of weldable thin sheet material and shaped to provide the required magnetic head flexibility, mobility and spring loading, while affording structural rigidity and dimensional stability in the disk memory drive environment. Unwanted magnetic head displacements are additionally minimizing by employing materials in the magnetic head suspension assembly, including the actuator, the arm and the load beam or flexure, having the same, or nearly the same, thermal expansion coefficients.

Abstract: A thin film magnetic data transducer which prevents capacitive coupling between the transducer and the disk of a disk drive system, has a magnetic circuit which is maintained at the same potential as the disk, usually ground potential. With the disk and the magnetic pole tips of the magnetic circuit at the same potential, capacitive charging and consequent current flow or arcing or discharge noise between the two are prevented. Noise from current due to the variable capacitive coupling of the coil to the disk during disk rotation is also eliminated. The thin film magnetic transducer is fabricated by depositing successive layers of an electrical insulating material, a magnetic material, insulating material, electrical conducting material for a planar coil, insulating material and magnetic material, in the order named on a substrate.

Abstract: A disk drive having a disk stack and a movable actuator movable between position limits for moving one or more transducers between inner and outer radial limits with respect to the disk stack, established by a crash stop structure having at least one crash stop arm or projection for engaging the movable actuator and limiting actuator travel. The crash stop projection is stiff in the direction of actuator impact forces and is also displaceable from crash stop position in a direction different from the direction or impact forces, but biased to crash stop position, to permit forcible displacement of the crash stop projection in the different direction so that the actuator may be moved therepast during actuator installation or removal when assembling or disassembling the disk drive.

Abstract: A magneto optical head assembly combining a single high extinction polarizing beam splitter utilized to separate and analyze a light beam, a pair of half-wave plates, each having a fast axis with respect to the polarization direction of light transmitted through the head assembly, with the angle of the fast axis of one of the half-wave plates preferably being equal but opposite that of the angle of the fast axis of the remaining half-wave plate. The light beam is transmitted through the head assembly polarizing beam splitter to be polarized with one half of the transmitted polarized light passing through one of the half-wave plates and the remaining half of the transmitted polarized light passing through the other half-wave plate. The portion of the transmitted polarized light which passes through each half-wave plate is rotated about the fast axis of each plate and focused upon a point on a magnetic recording medium.

Abstract: A method and apparatus for producing position error signals from a beam of light, called an input light beam, reflected from an optical surface of recording media, employs a detector prism which has a steep angle, reflection/transmission interface. A prism, such as a dove prism, separate from the detector prism, or other optical structure, integral with the detector prism, having one or more Brewster angle faces on which the input light beam is incident, is employed for inverting a portion of equal portions of the input light beam prior to incidence of the resulting beam on the reflection/transmission interface of the detector prism. Crossing of the marginal rays in the transmitted and reflected complementary light beams now does not invert the slope of the error signal. Now the error signal is not bilaterally sensitive in the respective complementary light beams.

Abstract: An optical assembly incorporating a wedge-shaped optically transparent prism, a 45 degree right isosceles triangular prism which has two thin film coated surfaces, a rhomboidal prism attached to the triangular prism, a second, smaller 45 degree right isosceles triangular prism attached to one end face of the rhomboidal prism and two planoconvex lenses attached to the combination of the rhomboidal and second triangular prisms is mounted within a housing. All of the optical components are cemented to the adjacent component utilizing a transparent optical cement to form an integral unit.

Abstract: A linear or rotary disk memory drive having provision for compensating or cancelling track position syncopation. Due to interference among the magnetic fields of magnetic dibits recorded in and adjacent to a servo code field in a magnetic memory disk, magnetic field intensities are displaced, producing an indication of a track center displaced from the actual track center. A magnetic head tracking such displaced magnetic fields is consequently displaced from track center, which is unacceptable. Four phases of magnetic dibits of servo code are recorded in each of at least four consecutive circumferential frames in a memory disk, in differing servo code formats or patterns of magnetic dibits.

Abstract: An actuator lock for a disk drive in which fixed air vanes projecting between a adjacent disks divert air flow, generated by disk rotation, into a narrowing passage adjacent the disks to impinge upon an air vane forming part of a rotatably mounted actuator lock, to angularly move the actuator lock to release an actuator assembly for movement of the magnetic heads thereon in track seeking and track following operations.

Abstract: A disk drive having a base and a cover, enclosing the memory disks and the magnetic head actuator. The spindle journaling the memory disks and the support for the actuator are secured to the base and to the cover and relatively position the base and the cover with respective peripheral extremities in closely spaced, but not touching relationship, to provide a gap therebetween. A pressure sensitive adhesive tape of a material having a high shear strength is applied to the base and the cover bridging the gap without applying stresses to the cover or the base through the tape and providing a seal for the disk drive between the cover and the base. The materials of the base, the cover, the spindle and the support, have thermal coefficients of expansion which are at least substantially the same. Preferably the materials are the same. Steel is a preferred material.