Abstract: A magnetic storage apparatus includes a magnetic storage medium including a recording layer, and a backing layer including a portion having a Curie temperature lower than that of the recording layer, a recording head that generates a magnetic field for recording from a side of the recording layer opposite to another side on which the backing layer is provided, and a heater unit heating at least a part of an area in proximity to a target area for recording by the recording head.
Abstract: A head slider includes a medium opposing surface configured to oppose a recording surface of a magnetic recording medium, a head element provided on the medium opposing surface, and an outlet end surface provided on a downstream side of the head element in a direction in which the magnetic recording medium moves relative to the head element, and extending substantially in a perpendicular direction from the medium opposing surface. The outlet end surface has a surface free energy greater than a surface free energy of the medium opposing surface.
Abstract: A program processing device has a non-volatile storage, a volatile storage and a controller. The controller has a detector that detects a bit flip in the program, the variable data, and the constant data in the volatile storage, a constant recovery unit that, when the detector detects an error in the constant data, writes the constant data in the non-volatile storage into the volatile storage, and then continues the execution of the program from a point at which the program was being executed before the detector detected the error, and a restart that, when the detector detects an error in one of the variable data and the program, writes the program, the initial value of the variable data, and the constant data in the non-volatile storage into the volatile storage, and then executes the program written into the volatile storage from a beginning of the program.
Abstract: A disk-drive magnetic circuit fixing structure and fixing method for fixing a magnetic circuit to a base by means of a plurality of screws, wherein provisions are made to substantially prevent a microscopic sliding movement involving impulsive vibration from occurring at a fastening portion between the magnetic circuit and the base. More specifically, in a disk drive including a disk enclosure having a base and a cover, a magnetic head contained within the disk enclosure, and a driving coil motor for driving the magnetic head by working in combination with an actuator on which the magnetic head is mounted and a magnetic circuit disposed in the vicinity of the actuator, the magnetic circuit is fixed to the base with a single or a plurality of screws by applying in advance a lubricant forming a lubricating layer on a face where each screw contacts the magnetic circuit or the base.
Abstract: According to one embodiment, a magnetic recording medium to which a signal is recorded by reversing magnetization of a magnetic body, includes: a servo region to which a servo signal is written; a data region configured to include a magnetic region of a track to which data is written, the magnetic region being separated from other magnetic region of other track; and a periodic magnetic pattern region configured to be provided at a head portion of the data region following the servo region, and is inclined at a predetermined angle with respect to a circumferential direction of the magnetic recording medium, over a predetermined length in a radius direction of the magnetic recording medium.
Abstract: A magnetic storage apparatus has a reproducing head to reproduce information from a perpendicular magnetic recording medium that is recorded with servo information, eccentricity correction data and read/write data. The apparatus further has a filter part to filter a reproduced output of the reproducing head by filtering the servo information which has a differentiated waveform by a non-differentiating characteristic and by filtering the eccentricity correction data and the read/write data which have rectangular waveforms by a differentiating characteristic, a demodulating part to demodulate the servo information, the eccentricity correction data and the read/write data that are filtered by the filter part, and a servo system to carry out a control process including an eccentricity control based on the servo information and the eccentricity correction data that are demodulated.
Abstract: According to one embodiment, a storage apparatus includes: a read section that receives a predetermined electrical parameter to read out data from a recording medium; a characteristic detection section that detects a plurality of characteristic values corresponding to a plurality of different predetermined electrical parameters received by the read section, respectively, the characteristic values being predetermined indicators of the read section, respectively; a characteristic relation acquisition section that acquires a slope of a characteristic value versus a predetermined electrical parameter from the predetermined electrical parameters and the characteristic values; and a determination section that determines presence/absence of failure in the read section based on the slope acquired by the characteristic relation acquisition section.
Abstract: A data storage apparatus includes: a medium for storing data having synchronization marks and data blocks, the synchronization mark and the data block being allocated alternately in the circumference direction of the medium; a head writing data into or reading out data from the medium; and a processor for executing a process including: reading out synchronization marks, measuring time for the head to pass through each of the data blocks based on signals read out from each of the synchronization marks in the circumference direction, generating write/read clock for each of the data blocks, which is continuously changing in speed, by calculating difference in time for the head to pass through the each one of the data blocks and its adjacent one of the blocks on the basis of the time measured, and writing data into or reading out data from the medium in synchronization with the write/read clock.
Abstract: A magnetic recording device includes: a magnetic recording medium including a write-synchronization region and a data region; a correction-value-storage unit configured to store therein a phase-correction value for correcting a phase of the write clock; a reading unit configured to read out a signal from the magnetic recording medium; a write-clock generator configured to generate the write clock based on a write-reproduction signal which is a signal read out from the write-synchronization region by the reading unit; a phase-correction unit configured to correct the phase of the write clock generated by the write-clock generator based on the phase-correction value stored in the correction-value-storage unit; and a data acquisition unit configured to acquire data included in a data-reproduction signal which is a signal read out from the data region by the reading unit based on a clock that is generated by correcting the phase by the phase-correction unit.
Abstract: A magnetic storage medium includes: burst lines each including magnetic bodies placed in a nonmagnetic body in a predetermined repetitive pattern repeated in the radial direction, the burst lines arranged in the circumferential direction at predetermined intervals, wherein the phases of the predetermined repetitive patterns are shifted in the radial direction relative to a circumferential line at least between the adjacent ones of the burst lines.
Abstract: According to one embodiment, a micro actuator device, includes: a first piezoelectric element superposed on a first lower support plate coupled to a fixed plate; a second piezoelectric element superposed on a second lower support plate in parallel with the first lower support plate coupled to the fixed plate; a first upper support plate interposing the first piezoelectric element between the first upper support plate and the first lower support plate, and generating strain equal to strain of the first lower support plate when a tensile force of the first piezoelectric element acts on the first lower support plate; and a second upper support plate interposing the second piezoelectric element between the second upper support plate and the second lower support plate, and generating strain equal to strain of the second lower support plate when a tensile force of the second piezoelectric element acts on the second lower support plate.
Abstract: According to one embodiment, address information is expanded on a bit map in order to generate original address information which is divided in a direction of the abscissa to form groups. The demodulated values of the original address information are obtained as original intra-group demodulated values. New address information is obtained and an arrangement pattern of bits in the servo area determined based on the new address information on a bit map formed by integrating obtained new address information items of the groups.
Abstract: An atmospheric pressure measuring apparatus allows a transmitter to transmit an acoustic wave for measurement of the atmospheric pressure. Air propagates the acoustic wave. A receiver receives the acoustic wave. Since the intensity of the acoustic wave changes to follow the variation of the atmospheric pressure, the atmospheric pressure can be measured based on the intensity of the acoustic wave received at the receiver. The atmospheric pressure is in this manner measured with such a simplified structure.
Abstract: According to one embodiment, a position control apparatus includes: a digital control module that performs position control including disturbance adaptive control with a predetermined sampling period with the use of a control constant, in accordance with a position error between a target position and a current position of the object; and a table that stores the control constant corresponding to a value of sin(?T/2), wherein the digital control module determines a control value of the actuator in accordance with the position error, calculates the value of sin(?T/2) according to an adaptive law from a signal based on the position error, reads the corresponding control constant from the table in accordance with the calculated value of sin(?T/2), and updates the control constant.
Abstract: A storage apparatus includes a magnetic storage medium which is formed with a data portion based on isolated magnetic dots and a servo pattern portion, a drive mechanism which drives the storage medium, a head actuator which includes a head for reading and writing data from and to the storage medium, and a permanent magnet which is disposed at a position that is opposable to a whole radial region of the servo pattern portion, during a rotation of the storage medium.
Abstract: Upon receipt of a read command or a write command from an external device, a disk apparatus stores an obtained address as a primary address and a secondary address in an address storing unit, increments a counter value of the secondary address, and selects the secondary address of which the counter value indicates the largest number. Upon receipt of the read command for the primary address, the disk apparatus reads data specified by the primary address from a disk and stores it in a buffer memory in advance. Upon receipt of the read command, the disk apparatus sends the data from the buffer to the external device.
Abstract: According to one embodiment, a magnetic recording apparatus includes: an information recording module configured to record a predetermined number of lines of information with a predetermined length in an information recording region of a magnetic recording medium, each of the lines of information having a same recording start position with respect to a relative movement direction of the magnetic recording medium and a recording element, the each of the lines of information being provided with an overlaying portion of adjacent lines of information. The information recording module is configured to record clock information in one or a plurality of the lines of information.
Abstract: A storage device includes: a storage unit for writing data into a rotating storage medium via a writing head; a nonvolatile memory; a temporary storage memory for storing a plurality of writing commands temporarily; and a controller for executing the plurality of writing commands so as to selectively write data into the storage unit or the nonvolatile memory, rearranging the writing commands stored in the temporary storage memory in accordance with efficiency for executing the writing commands to write data into the storage unit, sequentially executing the rearranged writing commands in descending order, and executing in parallel at least one of the writing commands that has not been executed to write data into the nonvolatile memory until all the data to be written in accordance with the writing commands are stored in either the storage unit or the nonvolatile memory.
Abstract: According to one embodiment, a position control apparatus includes: a digital control module that performs position control including disturbance adaptive control with a predetermined sampling period using a control constant, in accordance with a position error between a target position and a current position of the object; and a table that stores the control constant corresponding to a value of sin(?T) or cos(?T), wherein the digital control module is configured to determine a control value of the actuator in accordance with the position error, calculates the value of sin(?T) or cos(?T) according to an adaptive law from a signal based on the position error, reads the corresponding control constant from the table in accordance with the calculated value of sin(?T) or cos(?T), and updates the control constant, to perform the position control including the disturbance adaptive control.
Abstract: An access control apparatus includes a memory and a command executor executing an access process on a command with the command completion time limit. An address of an inaccessible recording area is stored in the memory. Data attempted to be written on the inaccessible recording area is obtained. The data is stored in association with the address in the memory. An automated alternate processor executes the automated alternate process of the inaccessible recording area in a predefined period of time after the process executed by the command executor is completed. A memory updater deletes the address of the inaccessible recording area whose automated alternate process has succeeded and the data attempted to be written in the recording area at the address.