Abstract: A magnetic storage medium such as a BPM includes a plurality of magnetic dots for writing and reproducing data disposed in a magnetically separated manner so as to be spaced a predetermined distance in a down-track direction and a plurality of tracks concentrically disposed so that the magnetic dots are disposed in a magnetically separated manner. In the BPM, a phase-adjusting track is disposed in an arbitrary track among the tracks. On the phase-adjusting track, phase detection dots disposed in a down-track direction to allow writing and reproduction of phase detection data and blank bits providing a predetermined phase difference in a down-track direction to next successive phase-detecting dots are alternately disposed in a successive manner.

Abstract: A patterned media type magnetic storage medium has separated magnetic dots formed a data area having a first magnetic dots and a servo area. The micro position detection portion in the servo area is constructed with first and second dot arrays having a different number of second magnetic dots in the circumference direction and face with the center line that the first magnetic dots of the data area in the magnetic storage medium are disposed, as the axis. The area of the magnetic dot constituting the micro position detection portion of the servo area is small, so the coercive force of the servo area increases. The frequency is changed depending on the number of magnetic dots, and the phase is changed depending on the position of the magnetic dot array in the radius direction with the center line as an axis.

Abstract: A magnetic disk apparatus includes a computing unit that obtains data to be recorded on a magnetic disk and computes an intermediate bit length based on a longest bit length and a shortest bit length of bit lengths of the obtained data; an adjusting unit that adjusts a strength of a recording current for recording the obtained data based on a difference between the intermediate bit length and a bit length of the obtained data; and a recording unit that repeatedly detects an error rate for recording data by using the adjusted recording current while narrowing down a track width on the magnetic disk and records the obtained data with a track width corresponding to an error rate detected immediately before an error rate that is detected to be equal to or greater than a predetermined value.

Abstract: An information storage apparatus includes a housing; a recording medium in which information is recorded, disposed in the housing; a head that records/reproduces information onto/from the recording medium by making contact with or approaching to a surface of the recording medium; a head holding member for holding the head, being rotatable about a predetermined axis and moving the head along the recording medium; a driving section that drives the head holding member to rotate about the axis; a rotation restricting member disposed in a position where the head holding member collides, and that restricts a rotation area of the head holding member; a temperature change detecting section that detects temperature change in the housing; and a drive controlling section that causes the driving section to drive the head holding member to collide with the rotation restricting member, when a detection result by the temperature change detecting section indicates temperature change.

Abstract: A recording processing unit sets a track pitch narrower than a writing width of a recording element so that part of the recorded track overlapped with the unused track is overwritten, and continuously records information on a disk medium toward one direction in accordance with the track pitch. A first offset correcting unit reads a write/read offset from a storage table, in which the write/read offset is measured and saved in advance, and corrects the write/read offset in the state that a reading element is positioned at a target track. A second offset correcting unit corrects a write-once center offset, which is a positional deviation between a read center position of the reading element, which has undergone correction of the write/read offset by the first offset correcting unit, and a center position of an effective track width caused by write-once recording.

Abstract: A data storage device includes: a recording medium that has two or more system data recording areas where system data are recorded on a multiple basis, and a user data recording area where user data is recorded; a head that writes and reads data into and from the recording medium; and a system data update control section that causes the head to update the system data on the recording medium. The system data update control section causes the head to record new system data on a multiple basis in another sub-record area that is alternately selected at each update to the new system data over the two or more system data recording areas when each the two or more system data recording areas is divided into two sub-record areas, and read the new system data from the another sub-record area to confirm that the new system data is recorded correctly.

Abstract: A magnetic storage device includes a magnetic disk having a protective film and a lubricant layer formed on the protective film, a head stack assembly including a head operable to read information from and write information to the magnetic disk, and a suspension configured to support the head, a vibration detection sensor operable to output a detection signal to detect vibration of the head stack assembly, and an extraction unit operable to extract a specific frequency range from the detection signal outputted by the vibration detection sensor, the specific frequency range including a natural frequency of the head stack assembly but not including a natural frequency of an air film on the head.

Abstract: A screwing apparatus includes a support member having a horizontal support surface. A single urging member has an urging surface opposed to the support surface. The urging surface is set parallel to the support surface. A driving mechanism is configured to drive at least one of the support member and the urging member to move to change the distance between the support member and the urging member. Driver bits have the tip ends opposed to the support surface, respectively. The driver bits are driven to move toward and away from the urging surface.

Abstract: A bending apparatus of a head gimbal assembly includes a suction unit configured to attract the head gimbal assembly, a movement unit configured to move a long tail connected to a terminal part, a stopper against which the moved long tail is butted, a transmission type optical sensor configured to detect that the long tail is positioned to the stopper, a tail holder configured to hold a part of the long tail on a work table, a roller configured to compress the terminal part against the tail holder and to bend the terminal part relative to the long tail at a right angle, and a controller configured to control, based on a detection result of the transmission type optical sensor, a movement of the tail holder to the work table and a movement of the roller to the tail holder.

Abstract: According to an aspect of the embodiment, in a magnetic recording apparatus having a magnetic recording medium of a patterned media system, a voltage generated between both terminals of a magnetic field generating coil in a case that a DC current is supplied to a recording element of a magnetic head is measured by a voltage measuring circuit in order to perform accurate recording at the center of each of magnetic body regions sectioned with non-magnetic body regions. Based on the measured voltage, a change in coil inductance in passage of the magnetic head over a magnetic body region and a non-magnetic body region in a patterned media is detected by a voltage change detecting circuit. A write clock signal which synchronizes with the change in coil inductance is generated by a clock signal generating circuit.

Abstract: According to an aspect of an embodiment, a memory device has a medium including a plurality of tracks, each of which has a plurality of sectors separated by a plurality of servo areas, for storing data in the sectors of the tracks, a head for writing data into and reading data from the medium and a controller for determining whether the head has read out data from a sector on a target track correctly or not in reference to information obtained from servo areas sandwiching the sector and for driving the head so as to retry reading out data from the sector when the controller determines that the head failed to have read out data on the target track.

Abstract: According to one embodiment, a servo pattern writing method includes: moving a head from a first one of innermost and outermost circumferences of a medium to the remainder other than the first one while controlling a position of the head in accordance with a temporary pattern preliminarily written on the medium; calculating a junction between a servo pattern to be written from the innermost circumference and a servo pattern to be written from the outermost circumference based on a movement distance of the head; first writing the servo pattern from a second one of the innermost and outermost circumferences to the junction, while controlling the position of the head in accordance with the temporary pattern; and second writing the servo pattern from the remainder other than the second one to the junction, while controlling the position of the head in accordance with the temporary pattern.

Abstract: In a data storage device, a head writes data so as to protect data from off track writing to adjust tracks. A control unit acquires large ring buffer during sequential writing and performs a retry to return adjacent tracks, according to data of a return sector area of the ring buffer when a write error occurs. A write error due to a detection mistake of an off track error can be prevented.

Abstract: The tip end of the bonding tip is defined between first and second edges. A first inclined surface gets remoter from a first terminal at a position remoter from the first edge. The second inclined surface likewise gets remoter from the first terminal at a position remoter from the second edge. The solder is contoured by first and second contours on the first terminal. The second terminal is located on the solder between the first and second contours. The tip end of the bonding tip is urged against the second terminal. Heat is transferred from the bonding tip to the solder. The melted solder spreads into gaps between the second terminal and the first and second inclined surfaces. The solder is thus prevented from spreading outside the contour of the first terminal. This results in a reliable avoidance of a short circuit between the adjacent first terminals.

Abstract: According to one embodiment, a recording medium driving device includes: a recording medium including a plurality of groove regions and land regions, wherein each of the groove regions is formed in a groove formed on top surface of the recording medium and having an arrangement of a magnetic domain formed for each bit, and each of the land regions forms a flat surface on the top surface of the recording medium and in between a pair of the groove regions in adjacency; a head slider disposed to face the top surface of the recording medium; a head element mounted on the head slider; a heater mounted on the head slider and configured to cause a projection in the head element by heat; and a control circuit configured to cause the projection to contact with the land region at time of performing zero calibration for the projection.

Abstract: A head position control method controls the position of a head by correcting components synchronizing rotation of a disk based on the head control amount. A correction signal for components synchronizing rotation is generated by using a filter function. The filter function that integrates the sine and cosine terms of DFT and inverse DFT and forms multiply of the complex values a(m) and b(m) and sine and cosine for frequency conversion, is measured in advance. The complex values are the m degree of RRO frequencies having frequency characteristics to be multiplied (1+C(z) P(z)) or ?(1+C(z) P(z)/P(z)).

Abstract: According to one embodiment, an actuator arm includes a joint, an extension, a pair of outer surfaces, and a linear protrusion. The joint is rotatably supported on a shaft. The extension extends from the joint and has a tip end connected to a head that performs at least reading or writing with respect to a rotating disk recording medium. The outer surfaces are in a front-and-rear relationship with each other. At least one of the outer surfaces faces the disk recording medium. The linear protrusion is arranged on and extends along an edge of at least one of the outer surfaces. The edge is located upstream on the outer surfaces in a flowing direction of an air flow generated by the rotation of the disk recording medium.

Abstract: According to one embodiment, a data storage device, includes: a recording medium, statuses of storage areas of the recording medium being managed by groups; a managing table storage module storing a managing table in which bit information pieces are associated to indexes representing the groups, the bit information pieces indicating the statuses of the storage areas initially set to an erased status; a transfer controller storing, upon receiving a write command, data in the storage areas; and a controller updates the bit information pieces of one of the groups to which the storage areas belongs to a stored status. Upon receiving an erase command, the transfer controller overwrites the storage areas by predetermined data. The main controller is configured to update the bit information pieces to the erased status.

Abstract: According to one embodiment, a magnetic disk device includes a receiver, an encrypting-and-decrypting module, a read-and-write controller, a setting module, an order controller, an executing module. The receiver receives a command to write data to or read data from a recording medium segmented into a plurality of storage areas each corresponding to an encryption key. The command causes an access to at least one of the storage areas. The encrypting-and-decrypting module encrypts the data or decrypts the data using the encryption key. The read-and-write controller controls writing the data to the recording medium and reading data therefrom. The setting module sets the encryption key corresponding to the storage area accessed by the command to the encrypting-and-decrypting module. The order controller controls the execution order in which commands are executed and brings up the execution order of the command causing an access to the storage area. The executing module executes the commands in the execution order.

Abstract: According to one embodiment, a disk drive includes a disk medium, a read controller configured to perform a read control for information in the disk medium, a determiner configured to determine whether or not to ignore a read error in information as a read target depending on a type of the information, and a transmitter configured to transmit the information to a host device without read error detection for the information read by the read controller if the determiner determines to ignore the read error.