Patents by Inventor Toshiya Shiramatsu

Toshiya Shiramatsu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9484048
    Abstract: According to one embodiment, a magnetic head includes a write element, a read element, and a heating element disposed between the write element and the read element. When power is applied to the heating element, either the read element or the write element projects beyond a plane of an air-bearing surface (ABS) of the magnetic head, and when power is not applied to the heating element, a portion of the ABS of the magnetic head facing a magnetic disk close to the heating element has a concave shape. In another embodiment, when power is applied to the heating element, at least one of a portion of the read element and a portion of the write element approaches a magnetic disk, and when power is not applied to the heating element, a portion of the ABS of the magnetic head facing a magnetic disk close to the heating element has a concave shape.
    Type: Grant
    Filed: November 20, 2009
    Date of Patent: November 1, 2016
    Assignee: HGST Netherlands B.V.
    Inventors: Shinji Sasaki, Takateru Seki, Masayuki Kurita, Toshiya Shiramatsu
  • Patent number: 9159348
    Abstract: A method for measuring the head-disk clearance between a slider and a disk includes measuring a first resistance with a first bias applied to an embedded contact sensor of the slider, measuring a second resistance with a second bias applied to the embedded contact sensor of the slider, and determining the head-disk clearance based at least in part on a difference between the first resistance and the second resistance. A system includes a disk drive, a slider comprising an embedded contact sensor, and circuitry to apply at least two bias voltages to the embedded contact sensor, measure at least two resistances of the embedded contact sensor based on the application of the at least two bias voltages, and to determine the head-disk clearance based at least in part on a difference between the at least two resistances.
    Type: Grant
    Filed: December 17, 2013
    Date of Patent: October 13, 2015
    Assignee: HGST NETHERLANDS B.V.
    Inventors: Jianhua Li, Junguo Xu, Toshiya Shiramatsu, Takehiro Sato
  • Publication number: 20150170695
    Abstract: A method for measuring the head-disk clearance between a slider and a disk includes measuring a first resistance with a first bias applied to an embedded contact sensor of the slider, measuring a second resistance with a second bias applied to the embedded contact sensor of the slider, and determining the head-disk clearance based at least in part on a difference between the first resistance and the second resistance. A system includes a disk drive, a slider comprising an embedded contact sensor, and circuitry to apply at least two bias voltages to the embedded contact sensor, measure at least two resistances of the embedded contact sensor based on the application of the at least two bias voltages, and to determine the head-disk clearance based at least in part on a difference between the at least two resistances.
    Type: Application
    Filed: December 17, 2013
    Publication date: June 18, 2015
    Applicant: HGST NETHERLANDS B.V.
    Inventors: Jianhua Li, Junguo Xu, Toshiya Shiramatsu, Takehiro Sato
  • Patent number: 8873191
    Abstract: An embedded contact sensor (ECS) element for fly-height control and touchdown detection. An embedded contact sensor (ECS) element with a resistance that changes with a temperature change, which senses a clearance change between a head slider and a disk of a disk drive. A resistance measurement section, within said head IC, that determines a value of direct current resistance (DCR) of said ECS element, wherein said value of DCR changes with a temperature change, wherein said temperature change is caused by an air bearing cooling and frictional induced heating at a head disk interface. A resistance slope to fly-height conversion section that dynamically determines a target fly-height value for said head slider over said disk based on changes in said value of DCR.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: October 28, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Jianhua Li, Kenichi Kuramoto, Toshiya Shiramatsu, Yuichi Aoki, Masaru Furukawa, Yuichiro Sano
  • Publication number: 20140268386
    Abstract: An embedded contact sensor (ECS) element for fly-height control and touchdown detection. An embedded contact sensor (ECS) element with a resistance that changes with a temperature change, which senses a clearance change between a head slider and a disk of a disk drive. A resistance measurement section, within said head IC, that determines a value of direct current resistance (DCR) of said ECS element, wherein said value of DCR changes with a temperature change, wherein said temperature change is caused by an air bearing cooling and frictional induced heating at a head disk interface. A resistance slope to fly-height conversion section that dynamically determines a target fly-height value for said head slider over said disk based on changes in said value of DCR.
    Type: Application
    Filed: March 14, 2013
    Publication date: September 18, 2014
    Applicant: HGST Netherlands B.V.
    Inventors: Jianhua Li, Kenichi Kuramoto, Toshiya Shiramatsu, Yuichi Aoki, Masaru Furukawa, Yuichiro Sano
  • Patent number: 8773801
    Abstract: A magnetic-recording head with a first thermal fly-height control (TFC) element and an embedded contact sensor element (ECSE) configurable as a second TFC element. The magnetic-recording head includes a write element, a read element, a first heater element, and an ECSE. The write element is configured for writing data to a magnetic-recording disk. The read element is configured for reading data from the magnetic-recording disk. The first heater element is configured as a first TFC element to coarsely adjust a fly-height of the magnetic-recording head with respect to the magnetic recording disk. The ECSE is configured to detect a contact with the magnetic-recording disk, and to function as a second heater element that is configured as a second TFC element to finely adjust the fly-height. The first heater element is configured with a first stroke-length larger than a second stroke-length of the second heater element for adjusting the fly-height.
    Type: Grant
    Filed: October 21, 2010
    Date of Patent: July 8, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Masayuki Kurita, Toshiya Shiramatsu, Kenji Kuroki, Yuki Shimizu
  • Patent number: 8767338
    Abstract: A magnetic head slider is disclosed. The magnetic head slider includes a slider substrate and a laminated magnetic head element on the slider substrate. Additionally, the laminated magnetic head element includes a magnetoresistance effect element and a recording magnetic pole formed in a layer higher than the magnetoresistance effect element. A first thin-film resistor heater element is formed in a position further from an air bearing surface than the magnetoresistance effect element and the magnetic recording pole and a second film resistor heater element is formed in a layer lower than the first thin-film resistor heater element, and closer to the air bearing surface and the magnetoresistance effect element than the first heater element. A thin-film resistor sensor element is formed in a layer higher than the second thin-film heater element and closer to the air bearing surface than the second heater element.
    Type: Grant
    Filed: December 20, 2010
    Date of Patent: July 1, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Toshiya Shiramatsu, Masayuki Kurita, Hidekazu Kohira
  • Patent number: 8711508
    Abstract: A HDD including a magnetic disk, a magnetic head, an embedded contact sensor embedded in the magnetic head and configured to detect a contact between the magnetic disk and the magnetic head, and TFC embedded in the magnetic head and configured to facilitate in detecting the contact between the magnetic disk and said magnetic head.
    Type: Grant
    Filed: November 17, 2010
    Date of Patent: April 29, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Masayuki Kurita, Toshiya Shiramatsu, Yuki Shimizu
  • Patent number: 8593749
    Abstract: A hard-disk drive. The hard-disk drive includes a head-slider configured to fly in proximity with a recording surface of a magnetic-recording disk, and a fly-height variation compensator configured to generate a signal for compensating variation in fly height of a write element of the head-slider. The head-slider further includes the write element configured to write data to the magnetic-recording disk, a fly-height-adjustment heating element configured to displace the write element towards the magnetic-recording disk, and a position-adjustment heating element configured to displace the write element in at least a direction perpendicular to a flying direction. The fly-height variation compensator is further configured to add the signal for compensating variation in fly height to a control signal for output to the fly-height-adjustment heating element.
    Type: Grant
    Filed: December 10, 2009
    Date of Patent: November 26, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Takenori Atsumi, Irizo Naniwa, Toshiya Shiramatsu, Masayuki Kurita
  • Patent number: 8477455
    Abstract: A slider comprising a contact sensor element configured to respond to a change in resistance due to a change in temperature, and a shield structure. The shield structure comprises a lower thermal conductivity than the contact sensor element and a greater hardness than the contact sensor element.
    Type: Grant
    Filed: November 16, 2010
    Date of Patent: July 2, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Masaru Furukawa, Yuki Shimizu, Junguo Xu, Yohji Maruyama, Takayoshi Ohtsu, Toshiya Shiramatsu
  • Patent number: 8254061
    Abstract: A head-slider. The head-slider includes a slider and a magnetic-recording head formed on the slider. The magnetic-recording head includes a main pole, a return pole to which a recording magnetic field from the main pole returns, a sensor element, a shield provided between the sensor element and the main pole, and a heater element for adjusting a shape of a flying surface of the magnetic-recording head. The magnetic-recording head further includes a first recess provided at a tip end face of at least one element selected from the group consisting of the return pole and the shield, and a second recess provided on an exposed flying surface and corresponding to the first recess.
    Type: Grant
    Filed: November 10, 2009
    Date of Patent: August 28, 2012
    Assignee: Hitachi Global Storage Technologies, Netherlands B.V.
    Inventors: Kenji Kuroki, Masafumi Mochizuki, Toshiya Shiramatsu
  • Patent number: 8218405
    Abstract: Embodiments of the present invention provide a technique for projecting both a write element portion in writing and a read element portion in reading, and controlling a projecting distance of each write element and read element. According to one embodiment, a light absorbing member and a thermally expanding member are formed near a read element, and light is irradiated to the light absorbing member, thereby a read element is projected. Alternatively, light absorbing members, which absorb light having different wavelengths from each other, and thermally expanding members are formed near a write element and near the read element respectively, and a wavelength or intensity of light to be irradiated is changed, thereby a projecting distance of each of the write element and the read element is individually optionally controlled.
    Type: Grant
    Filed: April 14, 2009
    Date of Patent: July 10, 2012
    Assignee: HGST Netherlands B.V.
    Inventors: Masayuki Kurita, Toshiya Shiramatsu, Irizo Naniwa
  • Publication number: 20120120521
    Abstract: A HDD including a magnetic disk, a magnetic head, an embedded contact sensor embedded in the magnetic head and configured to detect a contact between the magnetic disk and the magnetic head, and TFC embedded in the magnetic head and configured to facilitate in detecting the contact between the magnetic disk and said magnetic head.
    Type: Application
    Filed: November 17, 2010
    Publication date: May 17, 2012
    Inventors: Masayuki Kurita, Toshiya Shiramatsu, Yuki Shimizu
  • Publication number: 20120120528
    Abstract: A slider comprising a contact sensor element configured to respond to a change in resistance due to a change in temperature, and a shield structure. The shield structure comprises a lower thermal conductivity than the contact sensor element and a greater hardness than the contact sensor element.
    Type: Application
    Filed: November 16, 2010
    Publication date: May 17, 2012
    Inventors: Masaru Furukawa, Yuki Shimizu, Junguo Xu, Yohji Maruyama, Takayoshi Ohtsu, Toshiya Shiramatsu
  • Publication number: 20120099218
    Abstract: A magnetic-recording head with a first thermal fly-height control (TFC) element and an embedded contact sensor element (ECSE) configurable as a second TFC element. The magnetic-recording head includes a write element, a read element, a first heater element, and an ECSE. The write element is configured for writing data to a magnetic-recording disk. The read element is configured for reading data from the magnetic-recording disk. The first heater element is configured as a first TFC element to coarsely adjust a fly-height of the magnetic-recording head with respect to the magnetic recording disk. The ECSE is configured to detect a contact with the magnetic-recording disk, and to function as a second heater element that is configured as a second TFC element to finely adjust the fly-height. The first heater element is configured with a first stroke-length larger than a second stroke-length of the second heater element for adjusting the fly-height.
    Type: Application
    Filed: October 21, 2010
    Publication date: April 26, 2012
    Inventors: Masayuki Kurita, Toshiya Shiramatsu, Kenji Kuroki, Yuki Shimizu
  • Patent number: 8125728
    Abstract: A disk drive. The disk drive includes a disk, a head-slider, a moving mechanism, and a controller. The head-slider includes a read/write element, a first heater element, a contact pad, and a second heater element. The read/write element includes a read element configured to read user data from the disk, and a write element configured to write user data to the disk. The moving mechanism is configured to support and to move the head-slider. The controller is configured to control the second heater element to control contact between the contact pad and the disk, and is configured to control clearance between the read/write element and the disk by using the first heater element with the contact pad in contact with the disk.
    Type: Grant
    Filed: November 25, 2009
    Date of Patent: February 28, 2012
    Assignee: Hitachi Global Storage Technologies, Netherlands B.V.
    Inventors: Masayuki Kurita, Toshiya Shiramatsu, Hidekazu Kohira, Kenji Kuroki
  • Patent number: 8125727
    Abstract: A disk drive. The disk drive includes a disk configured to store data, a motor configured to rotate the disk, a head-slider and a controller. The head-slider includes a slider configured to fly in proximity to a recording surface of the disk, and an element on the slider. The controller is configured to measure a fly height between the head-slider and the disk at different common-mode voltages of the element to determine an operational common-mode voltage from a measurement result.
    Type: Grant
    Filed: September 18, 2009
    Date of Patent: February 28, 2012
    Assignee: Hitachi Global Storgae Technologies, Netherlands B.V.
    Inventors: Kazushi Tsuwako, Yuusuke Matsuda, Masashi Murai, Toshiya Shiramatsu
  • Patent number: 8102625
    Abstract: Embodiments of the present invention provide a magnetic head slider capable of reducing thermal protrusion attributable to a heating mechanism for heat-assisted recording. According to one embodiment, a magnetic head slider for heat-assisted recording includes an insulating film formed on an end surface of a slider, and a read element, a write device and a heating mechanism for heating a recording medium embedded in the insulating film. The heating mechanism includes an optical waveguide and a near-field light emitting device. A heat radiating film of a material having a thermal conductivity higher than that of the insulating film is formed near the heating mechanism so that one end surface thereof is exposed in an air bearing surface.
    Type: Grant
    Filed: August 28, 2008
    Date of Patent: January 24, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Toshiya Shiramatsu, Kouji Miyake
  • Publication number: 20110149430
    Abstract: A magnetic head slider is disclosed. The magnetic head slider includes a slider substrate and a laminated magnetic head element on the slider substrate. Additionally, the laminated magnetic head element includes a magnetoresistance effect element and a recording magnetic pole formed in a layer higher than the magnetoresistance effect element. A first thin-film resistor heater element is formed in a position further from an air bearing surface than the magnetoresistance effect element and the magnetic recording pole and a second film resistor heater element is formed in a layer lower than the first thin-film resistor heater element, and closer to the air bearing surface and the magnetoresistance effect element than the first heater element. A thin-film resistor sensor element is formed in a layer higher than the second thin-film heater element and closer to the air bearing surface than the second heater element.
    Type: Application
    Filed: December 20, 2010
    Publication date: June 23, 2011
    Inventors: Toshiya Shiramatsu, Masayuki Kurita, Hidekazu Kohira
  • Publication number: 20110090586
    Abstract: A disk drive. The disk drive includes a disk configured to store data, a motor configured to rotate the disk, a head-slider and a controller. The head-slider includes a slider configured to fly in proximity to a recording surface of the disk, and an element on the slider. The controller is configured to measure a fly height between the head-slider and the disk at different common-mode voltages of the element to determine an operational common-mode voltage from a measurement result.
    Type: Application
    Filed: September 18, 2009
    Publication date: April 21, 2011
    Inventors: Kazushi Tsuwako, Yuusuke Matsuda, Masashi Murai, Toshiya Shiramatsu