Toshiba Assigned Seven Patents

Magnetic disk drive and rewrite processing
Kabushiki Kaisha Toshiba, Tokyo, Japan, has been assigned a patent (9,361,944) developed by Aoki, Shoichi, Yokohama Kanagawa, Japan, for a “magnetic disk drive and rewrite processing method.”

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”According to one embodiment, a magnetic disk drive including a disk including a plurality of track groups each including a first write track and a second write track partially overlapping the first write track, and a processor configured to count a write count corresponding to write processing of adjacent track groups for each of the plurality of track groups, and calculate an estimated time at which the write count reaches a particular value and, if a track group in which the estimated time is approximate is detected, read data of the approximate track group, and execute rewrite processing of writing the data to the track group in which the estimated time is approximate, at a time earlier than the estimated time.“

The patent application was filed on June 15, 2015 (14/739,462).

Disk storage apparatus and data storage
Kabushiki Kaisha Toshiba, Minato-ku, Japan, has been assigned a patent (9,354,817) developed by Aoki, Masatoshi, Yokohama, Japan, for a “disk storage apparatus and data storage method.”

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”According to one embodiment, a disk storage apparatus includes a disk, a detector, and a controller. The disk includes a first recording area for recording with a first track density, and a second recording area for recording with a second track density lower than the first track density. The detector is configured to detect a variation of an outside environment. The controller is configured to select a nonvolatile memory or the second recording area as a storage destination of write data transferred from a host, based on a content of the variation of the outside environment detected by the detector, and a state of capability or incapability of storage of the nonvolatile memory.“

The patent application was filed on January 28, 2015 (14/607,508).

Thermal-assisted magnetic recording device capable of writing magnetic
patterns on lower multi-step driving signals
Kabushiki Kaisha Toshiba, Tokyo, Japan, has been assigned a patent (9,336,813) developed by Tagami, Naoki, Yokohama Kanagawa, Japan, for a “thermal-assisted magnetic recording device capable of writing magnetic patterns on lower multi-step driving signals.”

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”According to one embodiment, there is provided a magnetic disk device including a light irradiation element and a control unit. The light irradiation element is configured to irradiate a magnetic disk with light according to a driving signal. The control unit is configured to lower, in multistep manner, active level of the driving signal contributing intensity of the light when a low frequency pattern of write data is recorded into the magnetic disk.“

The patent application was filed on January 26, 2015 (14/605,586).

Erase coarse guide spiral-based in-drive erase process
Kabushiki Kaisha Toshiba, Tokyo, Japan, has been assigned a patent (9,311,941) developed by Liang, Jiangang, San Jose, CA, Liu, Ting-Chun Janet, Cupertino, CA, Szita, Gabor, Mountain View, CA, and Calfee, Gary W., Santa Clara, CA, for a “erase coarse guide spiral-based in-drive erase process.”

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”In an in-drive erase process for erasing disk surfaces of a hard disk drive, erase spirals are written on multiple disk surfaces and at a different write frequency than that of other data patterns on the disk surfaces. The erase spirals written on a first disk surface can be used to control an erase process on a portion of the remaining disk surfaces. Erase spirals are then written on a different disk surface and can then be used to erase all data on the first disk surface. Consequently, even when every disk surface includes previously written data patterns that can potentially interfere with control of the erase process, the erase spirals so written can control the erase process with sufficient precision to thoroughly erase each disk surface.“

The patent application was filed on March 31, 2015 (14/675,507).

Determining oscillation characteristic
for high-frequency assisted magnetic recording device
Kabushiki Kaisha Toshiba, Tokyo, Japan, has been assigned a patent (9,305,584) developed by Koizumi, Gaku, Yokohama Kanagawa, Japan, and Taguchi, Tomoko, Kunitachi Tokyo, Japan, for a “determining oscillation characteristic for high-frequency assisted magnetic recording device.”

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”A magnetic disk device according to an embodiment includes a magnetic head including a write head with a high-frequency oscillator and a read head, a recording medium, a driving unit configured to moves the magnetic head on the recording medium, a measuring unit configured to obtain a first read signal with no current or a smaller current and a second read signal with a normal current supplied in the normal writing operation, a comparison unit configured to calculate comparative data indicating a comparison result between the first and second read signals, and a determination unit configured to determine an oscillation characteristic from the comparative data.“

The patent application was filed on February 19, 2015 (14/626,460).

Magnetic disk apparatus, controller and data processing
Kabushiki Kaisha Toshiba, Tokyo, Japan, has been assigned a patent (9,299,387) developed by Takada, Kazuya, and Yoshida, Kenji, Kamakura Kanagawa, Japan, for a “magnetic disk apparatus, controller and data processing method.”

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”According to one embodiment, a magnetic disk apparatus includes an RW channel with an internal memory for processing data to be read/written from/to a magnetic disk, a transfer controller for controlling data transfer between a host apparatus and the RW channel, and a processor for controlling the RW channel and transfer controller. The processor reads, from the magnetic disk, predetermined area data including to-be-rewritten data, subjects the read predetermined area data to error correction processing in the RW channel, and stores resultant data in the internal memory. The processor rewrites, with rewrite data from the host apparatus, the to-be-rewritten data of the predetermined area data stored in the internal memory to update the predetermined area data, adds an error correction code to the updated data in the RW channel module, and writes resultant data to the magnetic disk.“

The patent application was filed on September 10, 2014 (14/482,117).

Measuring method, manufacturing method for magnetic disk device
Kabushiki Kaisha Toshiba, Tokyo, Japan, has been assigned a patent (9,286,928) developed by Matsunaga, Toshitaka, Yokohama Kanagawa, Japan, for a “measuring method, manufacturing method for magnetic disk device, and magnetic disk device.”

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”According to one embodiment, a measurement method is applied to a disk device including a disk, and a head configured to protrude toward the disk when power is supplied thereto. In the method, a reference value for each of areas of the disk is acquired from a measurement-value distribution including pre-measured values that correspond to power supplied to a heater when the head is brought into contact with the disk. In each area, a data group calculated from the distribution and the reference value is acquired. An area where the data group has lower values than in the other areas is selected as a first area to be firstly measured. An area to be measured subsequent to the first area based on the data group is selected.“

The patent application was filed on June 29, 2015 (14/754,187).