Patents by Inventor Koichi Sakata

Koichi Sakata 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: 9519234
    Abstract: There is provided a carrier including magnetic core particles; and a coating layer on a surface of each of the magnetic core particles, wherein the coating layer contains electroconductive particles; wherein the electroconductive particles are electroconductive particles in which white inorganic pigments are coated with phosphorus-doped tin or tungsten-doped tin; and wherein a dope ratio of phosphorus or tungsten to tin in the phosphorus-doped tin or tungsten-doped tin is 0.010 to 0.100.
    Type: Grant
    Filed: June 26, 2013
    Date of Patent: December 13, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroyuki Kishida, Shigenori Yaguchi, Hiroshi Tohmatsu, Koichi Sakata, Hitoshi Iwatsuki, Toyoaki Tano
  • Patent number: 9372220
    Abstract: In a test of discharging a capacitor by electrically turning on a first switching element and a second switching element that are inserted in series in a conductor connecting a positive electrode and a negative electrode of the capacitor, a discharge current that passes through the first and second switching elements tend to apply stress on the first and second switching elements. In this discharge test, while a first control signal for putting the first switching element into a low resistance state is being applied to the first switching element, a second control signal increasing a voltage thereof over time is applied to the second switching element, and application of one of or both of the first and second control signals is stopped when a current detector detects a current. Since a discharge test ends when a limited discharge current starts flowing, stress associated with the discharge test is reduced.
    Type: Grant
    Filed: January 10, 2013
    Date of Patent: June 21, 2016
    Assignees: TOYOTA JIDOSHA KABUSHIKI KAISHA, DENSO CORPORATION
    Inventors: Takao Kanzaki, Koichi Sakata, Yusuke Shindo, Yasuaki Igarashi
  • Patent number: 9304427
    Abstract: A carrier for developing an electrostatic latent image of the present invention includes a core material and a coating layer which coats the core material, wherein the coating layer includes a resin and fine particles, wherein the coating layer has an average layer thickness difference of 0.02 ?m to 3.0 ?m, and wherein the carrier for developing an electrostatic latent image has an arithmetic mean surface roughness Ra1 of 0.5 ?m to 0.9 ?m.
    Type: Grant
    Filed: June 26, 2013
    Date of Patent: April 5, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Hitoshi Iwatsuki, Shigenori Yaguchi, Toyoaki Tano, Mariko Takii, Koichi Sakata, Hiroyuki Kishida, Hiroshi Tohmatsu
  • Patent number: 9298119
    Abstract: A carrier is provided. The carrier includes a particulate magnetic core, and a cover layer located on the surface of the particulate magnetic core and including a resin and a filler. When determined from observation of cross-section of the carrier, the shape factor SF2 of the carrier is from 120 to 160, the ratio of the average domain diameter of the particulate magnetic core to the number average particle diameter of the filler is from 1:1 to 1:0.003, and the area ratio of the filler in the cover layer is from 30 to 85%.
    Type: Grant
    Filed: January 29, 2014
    Date of Patent: March 29, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Shigenori Yaguchi, Koichi Sakata, Hitoshi Iwatsuki, Toyoaki Tano, Hiroyuki Kishida, Kenichi Mashiko, Hiroshi Tohmatsu
  • Publication number: 20160079751
    Abstract: A power supply system comprises a first battery, a second battery, an output electric circuit, a first switching element, a second switching element, and a third switching element. The output electric circuit includes a first electric circuit and a second electric circuit. The second electric circuit has a potential lower than a potential of the first electric circuit. The first, second and third switching elements are provided in series with each other from the first electric circuit toward the second electric circuit. The first battery is provided in parallel with the second switching element. The second battery is provided in parallel with a series connection between the second switching element and the third switching element.
    Type: Application
    Filed: September 10, 2015
    Publication date: March 17, 2016
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Akihiko IDE, Koichi SAKATA
  • Patent number: 9260019
    Abstract: A drive system includes a first switching unit, a first capacitor, a step-down circuit, a second capacitor, and a discharging unit. The first switching unit is configured to convert energy, stored in an electrical storage device, to electric power that is supplied to a motor. The first capacitor is connected to the first switching unit and configured to smooth voltage that is supplied from the electrical storage device to the first switching unit. The step-down circuit is connected to the first capacitor and configured to step down voltage of the first capacitor. The second capacitor is connected to the step-down circuit and configured to draw electric charge stored in the first capacitor. The discharging unit is configured to discharge electric charge stored in the second capacitor.
    Type: Grant
    Filed: April 4, 2014
    Date of Patent: February 16, 2016
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventor: Koichi Sakata
  • Patent number: 9261817
    Abstract: A replenishing developer housing container includes: a container body housing a replenishing developer; a conveying portion; a pipe receiving port; and an uplifting portion. The replenishing developer contains a toner and a carrier. The container body includes a protruding portion protruding from a container body interior side of the container opening portion toward one end of the container body and a curving portion curving so as to conform to the protruding portion. The uplifting portion includes an uplifting wall surface extending from an internal wall surface of the container body toward the protruding portion. When the replenishing developer housing container is mounted on the replenishing developer conveying device, the protruding portion is present between the curving portion and the replenishing developer receiving port of a conveying pipe being inserted.
    Type: Grant
    Filed: May 16, 2014
    Date of Patent: February 16, 2016
    Assignee: RICOH COMPANY, LTD.
    Inventors: Hitoshi Iwatsuki, Shigenori Yaguchi, Hiroshi Tohmatsu, Toyoaki Tano, Hiroyuki Kishida, Kenichi Mashiko, Koichi Sakata, Hiroshi Hosokawa, Shunji Katoh, Shinji Tamaki, Hiroshi Ikeguchi, Kenji Kikuchi, Michiharu Suzuki
  • Patent number: 9229347
    Abstract: A carrier for use in a two-component developer for developing an electrostatic latent image is provided. The carrier includes a particulate magnetic core; and a cover layer located on a surface of the particulate magnetic core and including a resin and a particulate electroconductive material. The carrier has a BET specific surface area of from 0.8 to 1.6 m2/g.
    Type: Grant
    Filed: December 16, 2013
    Date of Patent: January 5, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroyuki Kishida, Shigenori Yaguchi, Hiroshi Tohmatsu, Koichi Sakata, Hitoshi Iwatsuki, Toyoaki Tano, Kenichi Mashiko
  • Patent number: 9188878
    Abstract: At a carriage that shows a resonance mode in opposite phase to a resonance mode shown by a plate table where an interferometer which measures a position (a first controlled variable) of a plate stage driven according to a control input is installed, another interferometer is installed which measures a position (the second controlled variable) of the plate stage. By using the interferometer and the another interferometer, it becomes possible to design a driving system robust in a high bandwidth that drives the plate stage.
    Type: Grant
    Filed: January 27, 2012
    Date of Patent: November 17, 2015
    Assignees: THE UNIVERSITY OF TOKYO, NIKON CORPORATION
    Inventors: Hiroshi Fujimoto, Kazuaki Saiki, Koichi Sakata
  • Publication number: 20150293463
    Abstract: A synthetic controlled variable (Xmix=F1(Xc)+F2(X2, X1)) is obtained by obtaining a synthetic quantity (Xc=?X2+?X2) using measurement results (X2, X1) of a first and a second measuring instruments and corresponding gains (or transfer function) (?, ?) and synthesizing the synthetic quantity (Xc) and one of the measurement results (X2, X1) of the first and the second measuring instruments, respectively, via a high pass filter (F1) and a low pass filter (F2). A feedback control system is structured that obtains a control input (U) using a synthetic controlled variable (Xmix) and a desired value (R) and gives a plant the control input (U). This makes adding of a high pass filter for removing offset of installation position of the first and the second measuring instruments no longer necessary, and allows a driving system which controls robust driving in a high bandwidth of a plate stage (PST) regardless of bandwidth in which resonance appears to be designed.
    Type: Application
    Filed: July 9, 2013
    Publication date: October 15, 2015
    Applicant: NIKON CORPORATION
    Inventors: Koichi Sakata, Hiroyoshi Asaumi
  • Patent number: 9093920
    Abstract: A discharge controller carries out discharge control by determining a voltage to be applied to a conduction control terminal of each of switching elements such that a current in a non-saturation region of one of the switching elements is lower than a current in a non-saturation region of the other thereof, and applying the voltage to the conduction control terminal of each switching element with an opening-closing member opening an electrical path to turn on the switching elements, resulting in short-circuit of both electrodes of a capacitor so that a discharge current is outputted from the capacitor based on the discharge control. A manipulator manipulates, based on a value of the discharge current, how to apply the voltage to the conduction control terminal of the one of the switching elements, thus controlling an amount of heat to be generated in the one of the switching elements.
    Type: Grant
    Filed: March 30, 2011
    Date of Patent: July 28, 2015
    Assignees: DENSO CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Yoshiyuki Hamanaka, Tsuneo Maebara, Yusuke Shindo, Koichi Sakata
  • Publication number: 20150153665
    Abstract: There is provided a carrier including magnetic core particles; and a coating layer on a surface of each of the magnetic core particles, wherein the coating layer contains electroconductive particles; wherein the electroconductive particles are electroconductive particles in which white inorganic pigments are coated with phosphorus-doped tin or tungsten-doped tin; and wherein a dope ratio of phosphorus or tungsten to tin in the phosphorus-doped tin or tungsten-doped tin is 0.010 to 0.100.
    Type: Application
    Filed: June 26, 2013
    Publication date: June 4, 2015
    Inventors: Hiroyuki Kishida, Shigenori Yaguchi, Hiroshi Tohmatsu, Koichi Sakata, Hitoshi Iwatsuki, Toyoaki Tano
  • Patent number: 9029061
    Abstract: A carrier for use in a two component developer for developing an electrostatic latent image is provided. The carrier includes a particulate core material; and a cover layer located on a surface of the core material and including a silicone resin and barium sulfate. The cover layer includes Ba and Si at an atomic ratio of from 0.01 to 0.08 as determined by X-ray photoelectron spectroscopy.
    Type: Grant
    Filed: December 27, 2010
    Date of Patent: May 12, 2015
    Assignee: Ricoh Company, Limited
    Inventors: Koichi Sakata, Minoru Masuda, Hisashi Nakajima, Kimitoshi Yamaguchi, Yutaka Takahashi, Hitoshi Iwatsuki, Saori Yamada, Toyoaki Tano
  • Patent number: 8918025
    Abstract: To provide an image forming method, containing: a charging step, a latent electrostatic image forming step, a developing step, a transferring step, and a fixing step, wherein the developing step is developing the latent electrostatic image formed on the latent electrostatic image bearing member with a two-component developer containing a toner and a carrier by a developing element to form a visible image, where the developing contains: stirring the toner and the carrier to prepare the two-component developer to have a flow energy amount of 30 mJ to 70 mJ; and periodically discharging and transporting the stirred two-component to the developer unit by air pressure to thereby supply the two-component developer for the developing.
    Type: Grant
    Filed: July 13, 2012
    Date of Patent: December 23, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Tohmatsu, Shigenori Yaguchi, Hitoshi Iwatsuki, Toyoaki Tano, Koichi Sakata, Mariko Takii
  • Patent number: 8916325
    Abstract: A carrier for developing electrostatic latent image, including a particulate magnetic core material; and a coated layer covering the surface of the particulate magnetic core material, wherein the coated layer includes a resin including a silicone resin and a methacrylic ester or an acrylic ester resin, and a filler including a substrate; and an electroconductive layer comprising tin dioxide (SnO2), overlying the substrate, and wherein the carrier includes tin (Sn) in an amount not less than 0.5% by atom and has a ratio (Sn/Si) of tin (Sn) to silicon (Si) of from 0.03 to 0.2 when subjected to an XPS analysis.
    Type: Grant
    Filed: March 8, 2013
    Date of Patent: December 23, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Shigenori Yaguchi, Hiroshi Tohmatsu, Koichi Sakata, Hitoshi Iwatsuki, Hiroyuki Kishida, Toyoaki Tano
  • Patent number: 8903270
    Abstract: A developing device including a developer bearing member containing a magnetic field generator having multiple magnetic poles and a developer containing chamber is provided. The developer containing chamber contains a two-component developer comprising magnetic carrier particles having a saturated magnetization of 58 to 70 emu/g in a magnetic field of 1KOe and toner particles, and has a divider to define an upper supply chamber and a lower collection chamber. The supply chamber includes a supply conveyer to supply the two-component developer to the developer bearing member at an upstream side from the developing area. The collection chamber includes a collection conveyer to collect the two-component developer from the developer bearing member at a downstream side from the developing area. The multiple magnetic poles includes three developer bearing poles capable of bearing the developer on its surface.
    Type: Grant
    Filed: March 5, 2012
    Date of Patent: December 2, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Koichi Sakata, Shigenori Yaguchi, Toyoshi Sawada, Hitoshi Iwatsuki, Hiroyuki Kishida
  • Publication number: 20140348552
    Abstract: A replenishing developer housing container according to the present invention includes: a container body housing a replenishing developer; a conveying portion; a pipe receiving port; and an uplifting portion, wherein the replenishing developer contains a toner and a carrier, wherein the container body includes a protruding portion protruding from a container body interior side of the container opening portion toward one end of the container body and a curving portion curving so as to conform to the protruding portion, wherein the uplifting portion includes an uplifting wall surface extending from an internal wall surface of the container body toward the protruding portion, wherein the protruding portion is provided such that when the replenishing developer housing container is mounted on the replenishing developer conveying device, the protruding portion is present between the curving portion and the replenishing developer receiving port of a conveying pipe being inserted.
    Type: Application
    Filed: May 16, 2014
    Publication date: November 27, 2014
    Applicant: RICOH COMPANY, LTD.
    Inventors: Hitoshi Iwatsuki, Shigenori YAGUCHI, Hiroshi TOHMATSU, Toyoaki TANO, Hiroyuki KISHIDA, Kenichi MASHIKO, Koichi SAKATA, Hiroshi HOSOKAWA, Shunji KATOH, Shinji TAMAKI, Hiroshi IKEGUCHI, Kenji KIKUCHI, Michiharu SUZUKI
  • Patent number: 8877418
    Abstract: The developing method includes developing an electrostatic latent image on an image bearing member with a two-component developer including a toner and a carrier and born on at least one developer bearing member, whose surface moves at a linear speed of from 300 mm/sec to 2,000 mm/sec. The carrier includes a particulate core material; and a cover layer located on a surface of the core material and including a crosslinked material obtained by crosslinking a resin including a first unit having a specific tris(trialkylsiloxy) silyl group and a second unit having a specific alkoxysilyl group having a crosslinking ability. Each of the first unit and the second unit is included in the resin in a molar ratio of from 0.1 to 0.9 based on all the units included in the resin.
    Type: Grant
    Filed: July 19, 2011
    Date of Patent: November 4, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Hisashi Nakajima, Kimitoshi Yamaguchi, Shigenori Yaguchi, Hitoshi Iwatsuki, Toyoaki Tano, Mariko Takii, Minoru Masuda, Koichi Sakata, Saori Yamada, Hiroyuki Kishida
  • Publication number: 20140320047
    Abstract: A drive system includes a first switching unit, a first capacitor, a step-down circuit, a second capacitor, and a discharging unit. The first switching unit is configured to convert energy, stored in an electrical storage device, to electric power that is supplied to a motor. The first capacitor is connected to the first switching unit and configured to smooth voltage that is supplied from the electrical storage device to the first switching unit. The step-down circuit is connected to the first capacitor and configured to step down voltage of the first capacitor. The second capacitor is connected to the step-down circuit and configured to draw electric charge stored in the first capacitor. The discharging unit is configured to discharge electric charge stored in the second capacitor.
    Type: Application
    Filed: April 4, 2014
    Publication date: October 30, 2014
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventor: Koichi SAKATA
  • Publication number: 20140309827
    Abstract: A motor vehicle includes an electric motor, a smoothing capacitor, a discharge device and a controller. The smoothing capacitor smoothes the electric current that is used to drive the electric motor. The discharge device is capable of releasing the electric charge stored in the capacitor. The controller is configured to receive sensor data that indicates a state of the motor vehicle and determine whether to activate a discharge device, based on the sensor data received.
    Type: Application
    Filed: October 17, 2012
    Publication date: October 16, 2014
    Applicants: DENSO CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Takao Kanzaki, Koichi Sakata, Yusuke Shindo, Yasuaki Igarashi