| Patent application number | Description | Published |
|---|
| 20090154012 | Perpendicular magnetic recording head, magnetic head, and magnetic disk device mounted with these heads - Embodiments of the invention reduce generation of a magnetic field with a polarity reverse to that of the recording magnetic field, without deteriorating a gradient in the magnetic field. An embodiment of a magnetic disk device according to the present invention suppresses deviation and erase of already recorded data. In an embodiment, the perpendicular magnetic recording head includes the main magnetic pole, an auxiliary magnetic pole, a trailing shield disposed on the trailing side of the main magnetic pole with a non-magnetic film placed in-between, and side shields disposed on both the sides of the main magnetic pole in the direction of the track width with a non-magnetic film placed in-between. The trailing shield has on the trailing side a portion where film thickness is thinner on the trailing side than the thickness of its element in the height direction in its position facing the main magnetic pole. Adoption of this configuration allows suppression of generation of the magnetic field having a polarity reverse to that of the recording magnetic field, without deteriorating the magnetic field gradient. Also in the portion where the side shields face the main magnetic pole, the side shields have the portion where the film is thinned down in thickness. | 06-18-2009 |
| 20090161263 | Magnetic head and magnetic disk apparatus - Embodiments of the present invention provide a magnetic head for perpendicular magnetic recording, and a magnetic disk apparatus capable of preventing data erasure caused by alignment marks. In an embodiment, the magnetic head includes a head element including at least a main pole having a pole face on a flying surface and an auxiliary pole; alignment marks made of a magnetic material and used to detect the amount of lapping work when lapping the pole face of the main pole; and members made of a magnetic material, continuously extending in either direction with respect to the position of the main pole from within the alignment marks outward at least beyond the alignment marks. | 06-25-2009 |
| 20090168241 | Magnetic disk drive - Embodiments of the present invention help to inhibit record information in a perpendicular magnetic recording disk drive from being attenuated or erased due to leakage of a recording magnetic field into the already-recorded information. According to one embodiment, a magnetic disk includes a soft magnetic underlayer and a magnetic recording layer. A magnetic head includes a main magnetic pole, an auxiliary magnetic pole, a trailing shield which is disposed via a non-magnetic film on a trailing side of the main magnetic pole and in which a reverse side is in contact with the auxiliary magnetic pole, and side shields disposed on both sides of the main magnetic pole. Herein, where a saturation magnetic flux density of the soft magnetic underlayer is Bs | 07-02-2009 |
| 20100128376 | MAGNETIC DISK DRIVE HAVING ASSISTED RECORDING AND METHODS OF RECORDING DATA THERETO - In one embodiment, a magnetic disk drive includes a magnetic disk, a head slider for flying above the spinning magnetic disk, a pattern analyzer for analyzing a data pattern of data to be recorded on the magnetic disk to determine a recording current reversal timing and a recording assistance area in accordance with the analysis so that the rear end of the determined recording assistance area is shifted forward if the determined recording current reversal timing is earlier than a criterion, or the rear end of the determined recording assistance area is shifted backward if the determined recording current reversal timing is later than the criterion, a recording assistance element on the slider for forming the determined recording assistance area on the magnetic disk, and a recording element for recording the data on the magnetic disk using the recording current in accordance with the determined recording current reversal timing. | 05-27-2010 |
| 20100128382 | MAGNETIC RECORDING DEVICE AND MAGNETIC RECORDING METHOD THEREOF - A magnetic recording device according to one embodiment includes a magnetic recording medium having a magnetic recording layer; a recording element positioned on a head slider; an assistance element for supplying assistance energy to an area on the recording layer to which a recording magnetic field generated by the recording element is applied, the assistance element being positioned on the head slider; and a controller for controlling a size of an assistance area from the assistance element in accordance with a position of the head slider in a radial direction of the magnetic recording medium. Additional systems and methods are also presented. | 05-27-2010 |
| 20110038076 | DISK DRIVE AND METHOD OF RE-INJECTING LOW DENSITY GAS IN A HERMETICALLY SEALED DISK ENCLOSURE OF A DISK DRIVE - A method for re-injecting low density gas into a disk drive including a hermetically sealed disk enclosure. The method includes providing a disk drive including a hermetically sealed disk enclosure. In addition, the method includes re-injecting low density gas from a hole penetrating the hermetically sealed disk enclosure from an exterior of the disk drive to an interior of the disk drive. Moreover, the method includes covering the hole with a sealing label including a metal layer and an adhesive layer. | 02-17-2011 |
| 20110058274 | HARD-DISK DRIVE AND CONTROL METHOD FOR MAGNETIC RECORDING ON A PATTERNED MEDIUM OF THE HARD-DISK DRIVE - A hard-disk drive. The hard-disk drive includes a magnetic-recording disk including tracks on which a plurality of patterned bit-cells that are isolated magnetically are aligned at predetermined alignment pitches. The hard-disk drive includes a magnetic-recording head which is configured to follow tracks, and to write and to read data. The hard-disk drive includes a signal-processing unit which is configured to generate a recording signal based on a write-clock signal with cycles corresponding to alignment pitches of patterned bit-cells, and to output a recording signal. The hard-disk drive includes a phase-detecting unit which is configured to detect a phase of the write-clock signal when the magnetic-recording head reaches an end point of a predetermined range. The hard disk drive includes a determination-processing unit which is configured to determine success of data writing based on a difference between an expected value and a detected value of the phase of the write-clock signal. | 03-10-2011 |
| 20110069414 | HARD-DISK DRIVE - A hard-disk drive. The hard-disk drive includes a magnetic-recording disk in which tracks adjacent to each other are magnetically separated, a spindle motor which drives the magnetic-recording disk, a magnetic-recording head equipped with write element and read element, an actuator for positioning the magnetic-recording head on a predetermined track on the magnetic-recording disk, and a control unit. The control unit is configured to store information about an over-write-only track that is provided for a plurality of tracks including n consecutive tracks in at least a partial radial area of the magnetic-recording disk and an offset amount. In a radial area of the magnetic disk where the over-write-only track is located, the control unit is configured to record with an offset by an offset amount from a center of a track toward the over-write-only track with respect to n−1 tracks of the plurality of n tracks, excluding the over-write-only track. | 03-24-2011 |
| 20110096638 | HEAD-SLIDER INCLUDING A MAGNETIC-RECORDING ASSISTANCE ELEMENT, HEAD-ARM ASSEMBLY INCLUDING THE HEAD-SLIDER, AND HARD-DISK DRIVE INCLUDING THE HEAD-ARM ASSEMBLY - A head-slider configured to fly in proximity to a recording surface of a magnetic-recording disk. The head-slider includes a write element including a main pole configured to generate a magnetic-recording field from a pole tip of the main pole in a first localized portion of the magnetic-recording disk. The head-slider also includes a magnetic-recording assistance element configured to provide energy to a second localized portion of the magnetic-recording disk in order to increase reversibility of a magnetization in a first localized portion of the magnetic-recording disk. A width of the pole tip of the main pole on a leading-edge side is wider than a width of the pole tip of the main pole on a trailing-edge side. | 04-28-2011 |
