Toshiba Assigned Seven Patents

Magnetic disk device and high-frequency assist recording
Kabushiki Kaisha Toshiba, Tokyo, Japan, has been assigned a patent (9,870,789) developed by Funayama, Tomomi, Fuchu Tokyo, Japan, for a “magnetic disk device and high-frequency assist recording method.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “According to one embodiment, a magnetic disk device includes a magnetic recording medium, a head including a recording magnetic pole, a spin torque oscillator provided near the recording magnetic pole, and a coil which excites the recording magnetic pole, a first current supply which supplies the coil with a first current corresponding to write data, a detector which detects a first signal corresponding to the write data, and outputs a second signal in accordance with the first signal, and a second power supply which varies, in accordance with the second signal, a second current supplied to the spin torque oscillator.”

The patent application was filed on September 6, 2016 (15/257,029).

Disk, controller, and control
Kabushiki Kaisha Toshiba, Tokyo, Japan, has been assigned a patent (9,858,962) developed by Okubo, Tomokazu, Kawasaki Kanagawa, Japan, for a “disk apparatus, controller, and control method.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “According to one embodiment, there is provided a disk apparatus including a disk medium and a controller. The disk medium is able to store a signal with three levels in a track. The track includes a first subtrack and a second subtract. The second subtrack is adjacent to the first subtract. The controller performs a first operation based on a selected level among the three levels, a first bit written in the first subtract corresponding to the selected level, and a second bit written in the second subtrack corresponding to the selected level. The first operation is an operation to correct displacement between a write position of a third bit in the first subtrack and a write position of a fourth bit in the second subtrack in a circumferential direction of the disk medium.”

The patent application was filed on March 3, 2017 (15/449,073).

Disk and manufacturing
Kabushiki Kaisha Toshiba, Tokyo, Japan, has been assigned a patent (9,837,114) developed by Takaishi, Kazuhiko, Machida Tokyo, Japan, for a “disk device and method for manufacturing disk device.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A method for manufacturing a disk device includes the steps of measuring a first gain of a control signal of a fine motion actuator while positioning a head to a first radial position of a disk medium using a coarse motion actuator but not the fine motion actuator, based on an auxiliary servo pattern recorded on the disk medium, measuring a second gain of a control signal of the fine motion actuator while positioning the head to a second radial position of the disk medium using the coarse motion actuator but not the fine motion actuator, based on the auxiliary servo pattern recorded on the disk medium, and determining gain correction values which are to be applied to a control signal for the fine motion actuator while performing servo pattern writing on the disk medium, based on the first and second gains.”

The patent application was filed on March 3, 2017 (15/449,487).

Spiral write launch while servoing on reference guide spirals
Kabushiki Kaisha Toshiba, Tokyo, Japan, has been assigned a patent (9,824,708) developed by Liang, Jiangang, San Jose, CA, Szita, Gabor, Mountain View, CA, Huang, Tony, San Jose, CA, and Calfee, Gary W., Santa Clara, CA, for a “spiral write launch while servoing on reference guide spirals.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A reference spiral is written on a recording surface of a hard disk drive. By launching writing of fine guide spirals from a launch point that is disposed on a pre-existing coarse guide spiral, writing of the fine guide spiral can be launched in response to a write head crossing the pre-existing coarse guide spiral, rather than in response to a precisely timed event. To enable launch points being disposed on pre-existing coarse guide spirals, launch points are not all located at the same radial position on the recording surface.”

The patent application was filed on March 31, 2015 (14/675,482).

Disk, driver circuit, and control
Kabushiki Kaisha Toshiba, Tokyo, Japan, has been assigned a patent (9,824,707) developed by Kawabe, Takayuki, Sagamihara Kanagawa, Japan, Matsuzawa, Takuji, Kashiwa Chiba, Japan, and Hara, Takeyori, Kawasaki Kanagawa, Japan, for a “disk apparatus, driver circuit, and control method.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “According to one embodiment, there is provided a disk apparatus including a first disk, a second disk, a main actuator, a first actuator, a second actuator, a third actuator, and a driver circuit. The driver circuit is configured to be able to switch between a first mode and a second mode. The first mode is a mode where a first actuator, a second actuator, and a third actuator are driven in a same direction. The second mode is a mode where the first actuator and the second actuator are driven in opposite directions and where the third actuator and the second actuator are driven in opposite directions.”

The patent application was filed on March 9, 2016 (15/065,576).

Magnetic disk
Kabushiki Kaisha Toshiba, Tokyo, Japan, has been assigned a patent (9,805,759) developed by Kishino, Keiichi, Chigasaki Kanagawa, Japan, for a “magnetic disk device, adjusting method thereof, and manufacturing method thereof.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “An adjusting method for a magnetic disk device including a disk, a head that writes data on the disk, a controller circuit that outputs write data and a control signal related to the write data, and an integrated circuit that outputs a write current to the head, includes adding a delay to a timing of polarity inversion of one bit of the write data or the control signal, outputting the write data and the control signal added with the delay from the controller circuit to the integrated circuit, outputting from the integrated circuit to the head, the write current having a current value that is changed at one of timings of polarity inversion of the write data, according to the control signal, and adjusting a deviation between the write data and the control signal, based on the output write current.”

The patent application was filed on March 3, 2017 (15/449,355).

Low-overhead storage of hibernation file in hybrid disk drive
Kabushiki Kaisha Toshiba, Tokyo, Japan, has been assigned a patent (9,804,784) developed by Ehrlich, Richard M., Saratoga, CA, Dunn, Eric R., Cupertino, CA, Zayas, Fernando Anibal, Rangiora, New Zealand, and Schmidt, Thorsten, Livermore, CA, for a “low-overhead storage of a hibernation file in a hybrid disk drive.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A hybrid drive and associated methods provide low-overhead storage of a hibernation file in the hybrid hard disk drive. During operation, the hybrid drive allocates a portion of solid-state memory in the drive that is large enough to accommodate a hibernation file associated with a host device of the hybrid drive. In addition to the erased memory blocks that are normally present during operation of the hybrid drive, the portion of solid-state memory allocated for accommodating the hibernation file may include over-provisioned memory blocks, blocks used to store a previous hibernation file that has been trimmed, and/or non-dirty blocks.”

The patent application was filed on July 7, 2016 (15/204,739).