Patents by Inventor Tetsuya Miyazaki

Tetsuya Miyazaki 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).

  • Publication number: 20110211844
    Abstract: An optical gate switch circuit includes: an asymmetric Mach-Zehnder interferometer having an optical path that outputs control light and probe light to a second optical directional coupler via a first optical directional coupler and an optical phase modulation element, and another optical path that connects a third optical directional coupler to which the probe light is input, to the second optical directional coupler via a variable optical attenuator and an optical phase shifter; and a bandpass filter connected to the second optical directional coupler.
    Type: Application
    Filed: September 1, 2010
    Publication date: September 1, 2011
    Applicants: NATIONAL INSTITUTE OF INFORMATION AND COMMUNICATIONS TECHNOLOGY, NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Hidemi TSUCHIDA, Hiroshi ISHIKAWA, Takashi SHIMOYAMA, Abedin Kazi SARWAR, Tetsuya MIYAZAKI
  • Patent number: 7988243
    Abstract: A brake controller is provided that includes a braking force application mechanism that presses a friction member against a braked member so as to apply a braking force to a wheel of a vehicle; and a control unit. The control unit calculates an index, which indicates a difference between an expected braking effectiveness and an actual braking effectiveness, corrects a target value, which is set to control a pressing force of the friction member, in accordance with the index to reduce a variation in a braking effectiveness of the vehicle. The control unit further sets a variation range in accordance with a factor that causes the difference. The variation range limits a variation in a correction amount to correct the target value.
    Type: Grant
    Filed: February 14, 2007
    Date of Patent: August 2, 2011
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Tetsuya Miyazaki, Yoshiaki Irie, Rio Suda
  • Patent number: 7938493
    Abstract: A brake control system includes a wheel cylinder, a brake pedal, a master cylinder in which communication between it and an external master cylinder reservoir is cut off when the operating amount of the brake pedal is equal to or greater than a predetermined value, an internal reservoir, and a pump which selectively discharges hydraulic fluid in two directions, one being a direction that increases the hydraulic pressure in the wheel cylinder by drawing up hydraulic fluid from the internal reservoir, and the other being a direction that stores hydraulic fluid in the internal reservoir. The pump is driven to discharge hydraulic fluid in the direction that stores hydraulic fluid when communication is open between the master cylinder and the master cylinder reservoir, and driven to discharge hydraulic fluid in the direction that increases the hydraulic pressure when communication is cut off between the master cylinder and the master cylinder reservoir. A further invention is directed to a brake control method.
    Type: Grant
    Filed: February 9, 2009
    Date of Patent: May 10, 2011
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventor: Tetsuya Miyazaki
  • Patent number: 7883159
    Abstract: A brake control apparatus comprises: a braking force applying mechanism that brakes a wheel by pressing a friction member upon supply of a working fluid; and a control portion that computes a target value set for controlling the pressure of the working fluid by utilizing a detected temperature of the friction member so as to restrain fluctuations of the effect of the brake caused by temperature changes of the friction member. The control portion restricts the utilization of the detected temperature in the computation of the target value in case a decline of the detection accuracy of the friction member temperature is predicted to restrain the influence of the decline of the estimation accuracy of the friction member temperature on the braking force control.
    Type: Grant
    Filed: January 24, 2007
    Date of Patent: February 8, 2011
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventor: Tetsuya Miyazaki
  • Publication number: 20100301667
    Abstract: In a brake control system (10), a reservoir switch (60) detects a decrease in the amount of hydraulic fluid in a reservoir tank (26). An ECU (100) switches a master cutoff valve (22), a pressure increase valve (40), and a pressure decrease valve (42) and the like between open and closed. When a decrease in the amount of hydraulic fluid in the reservoir tank (26) is detected, the ECU (100) opens the master cutoff valve (22) to supply hydraulic fluid from a right front-wheel wheel cylinder (20FR) and a left front-wheel wheel cylinder (20FL) to a master cylinder (14), when release of a brake pedal (12) is detected.
    Type: Application
    Filed: November 20, 2008
    Publication date: December 2, 2010
    Applicant: Toyota Jidosha Kabushiki Kaisha
    Inventors: Takayuki Yamamoto, Masaaki Komazawa, Tetsuya Miyazaki
  • Publication number: 20100295363
    Abstract: A brake control system includes a wheel cylinder, a brake pedal, a master cylinder in which communication between it and an external master cylinder reservoir is cut off when the operating amount of the brake pedal is equal to or greater than a predetermined value, an internal reservoir, and a pump which selectively discharges hydraulic fluid in two directions, one being a direction that increases the hydraulic pressure in the wheel cylinder by drawing up hydraulic fluid from the internal reservoir, and the other being a direction that stores hydraulic fluid in the internal reservoir. The pump is driven to discharge hydraulic fluid in the direction that stores hydraulic fluid when communication is open between the master cylinder and the master cylinder reservoir, and driven to discharge hydraulic fluid in the direction that increases the hydraulic pressure when communication is cut off between the master cylinder and the master cylinder reservoir. A further invention is directed to a brake control method.
    Type: Application
    Filed: February 9, 2009
    Publication date: November 25, 2010
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventor: Tetsuya Miyazaki
  • Patent number: 7801451
    Abstract: An optical phase modulation circuit includes an optical phase modulation element, an optical bandpass filter, and an optical directional coupler, wherein control light with a wavelength of ?C is coupled with probe light with a wavelength of ?P using the optical directional coupler and input to the optical phase modulation element, the probe light that has been phase modulated by the optical phase modulation element is extracted through the optical band pass filter, and the phase of the probe light is modulated in response to the intensity of the control light.
    Type: Grant
    Filed: August 22, 2007
    Date of Patent: September 21, 2010
    Assignees: National Institute of Information and Communications Technology, National Institute of Advanced Industrial Science and Technology
    Inventors: Hidemi Tsuchida, Hiroshi Ishikawa, Takashi Shimoyama, Abedin Kazi Sarwar, Tetsuya Miyazaki
  • Publication number: 20100198476
    Abstract: A brake control system includes a first wheel cylinder that applies braking force to a first wheel according to hydraulic pressure; a second wheel cylinder that applies braking force to a second wheel according to hydraulic pressure; a brake actuator that receives current and individually controls the hydraulic pressure of the first wheel cylinder and the hydraulic pressure of the second wheel cylinder; a power supply that supplies the current to the brake actuator; and a control portion which sets a braking force distribution between the first wheel and the second wheel based on the state-of-charge of the power supply, and controls the brake actuator according to the braking force distribution.
    Type: Application
    Filed: August 6, 2008
    Publication date: August 5, 2010
    Applicant: Toyota Jidosha Kabushiki Kaisha
    Inventors: Tetsuya Miyazaki, Takayuki Yamamoto
  • Publication number: 20100131151
    Abstract: In a stroke sensor abnormality determining device, a stroke sensor detects the stroke of a brake pedal by detecting a voltage that varies in accordance with the stroke of the brake pedal. An abnormality determining section determines whether an abnormality has occurred in the stroke sensor on the basis of the voltage detected by the stroke sensor. A pedal position determining section determines whether the brake pedal is positioned near a stroke start end. If it is determined that the brake pedal is positioned near the stroke start end, the abnormality determining section does not determine that an abnormality has occurred in the stroke sensor.
    Type: Application
    Filed: July 4, 2008
    Publication date: May 27, 2010
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Iwao Izumikawa, Tetsuya Miyazaki
  • Patent number: 7722133
    Abstract: A hydraulic brake system for a vehicle includes a brake having a wheel cylinder that applies a braking force to a wheel, and a pressurizing device. The pressurizing device pressurizes the brake liquid and includes a suction portion for sucking a brake liquid, and additionally includes an output portion connected to the wheel cylinder. A linear solenoid valve includes at least one housing, and is connected to the wheel cylinder and to the suction portion of the pressurizing device. The solenoid valve includes a valve portion having a reciprocating valve member and a valve seat opposed to the valve member. A biasing member biases the valve member in one direction and a solenoid applies a drive force to the valve member in an opposite direction. In addition, a hydraulic-pressure-decrease restraining device restrains a decrease of pressure of the brake liquid in the housing.
    Type: Grant
    Filed: March 28, 2008
    Date of Patent: May 25, 2010
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Masakuni Suzuki, Tetsuya Miyazaki, Kumiko Akita, Takami Iwamoto
  • Patent number: 7697849
    Abstract: An optical transmitter generates a transmission signal having a frame as a unit, the frame including a single optical pilot signal with a constant optical phase and a plurality of phase-modulated optical data signals, and outputs the transmission signal into a transmission line. In a receiver, a splitter splits the optical signal input from the transmission line. On a second arm of a Mach-Zehnder interferometer, an optical gate transmits the optical pilot signal and a duplicator duplicates the optical pilot signal output from the optical gate at predetermined time intervals. A balanced optical receiver converts the interfered optical signal output from the interferometer into an electrical signal. A gate and a discriminator extract the data from the electrical signal output from the receiver.
    Type: Grant
    Filed: July 6, 2006
    Date of Patent: April 13, 2010
    Assignee: National Institute of Information and Communications Technology Incorporated Administrative Agency
    Inventors: Yukiyoshi Kamio, Tetsuya Miyazaki
  • Patent number: 7609974
    Abstract: An optical transmitter generates a transmission signal having a frame as a unit, the frame including a signal pilot signal with fixed amplitude and phase and two data bits to output the generated signal into a transmission line. In a receiver, a splitter splits the signal light from the transmission line. An optical delay delays the signal light for a 1-bit period. A first combiner combines the signal light from the transmission line and the output signal light from the optical delay. A photodetector converts the combined light into an electrical signal. A 3-bit optical delay, a second combiner, a BPF, and an oscillator generate a frame-timing signal. A gate separates a data from the output from the photodetector under the control of a gate control unit. A binary discriminator binary-discriminates the output signal from the gate.
    Type: Grant
    Filed: July 5, 2006
    Date of Patent: October 27, 2009
    Assignee: National Institute of Information and Communications Technology Incorporated Administrative Agency
    Inventors: Yukiyoshi Kamio, Tetsuya Miyazaki
  • Patent number: 7481500
    Abstract: An operation-characteristic obtaining apparatus including an operation-characteristic obtaining portion which obtains, as an operation characteristic of an electromagnetic control valve which includes a coil and which is opened and closed according to at least a relationship between (a) an acting force corresponding to a difference of respective pressures of a working liquid on either side of the electromagnetic control valve and (b) an electromagnetic drive force corresponding to an electric current supplied to the coil, a relationship between (c) a valve switching current as an electric current that is supplied to the coil of the electromagnetic control valve at a time when the electromagnetic control valve is switched between a closed state thereof and an opened state thereof and (d) a difference at the time of the respective pressures on either side of the electromagnetic control valve; and a leakage detecting portion which detects, when the operation-characteristic obtaining portion obtains the operation
    Type: Grant
    Filed: January 3, 2006
    Date of Patent: January 27, 2009
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Tetsuya Miyazaki, Masaaki Komazawa, Yoshito Tanaka
  • Patent number: 7483640
    Abstract: An optical multilevel-coded signal transmission system transmits information from an optical transmitter to an optical receiver through an optical transmission line using optical intensity and optical phase separately. The optical transmitter includes an inverted RZ signal light generator to generate an inverted RZ signal light intensity-modulated with a first data, and an optical phase modulator to phase-modulate the inverted RZ signal light according to a second data. The optical receiver includes a splitter to split a light input from the optical transmission line into first and second portions, an inverter to invert the first portion from the splitter, a first detector to detect the first data in the first portion inverted by the inverter, a converter to convert a phase-modulated signal included in the second portion from the splitter into an optical intensity-modulated signal, and a second detector to detect the second data in the optical intensity-modulated signal from the converter.
    Type: Grant
    Filed: September 30, 2004
    Date of Patent: January 27, 2009
    Assignee: National Institute of Information and Communication Technology, Incorporated Administrative Agency
    Inventor: Tetsuya Miyazaki
  • Publication number: 20080238186
    Abstract: A hydraulic brake system for a vehicle includes a brake having a wheel cylinder that applies a braking force to a wheel, and a pressurizing device. The pressurizing device pressurizes the brake liquid and includes a suction portion for sucking a brake liquid, and additionally includes an output portion connected to the wheel cylinder. A linear solenoid valve includes at least one housing, and is connected to the wheel cylinder and to the suction portion of the pressurizing device. The solenoid valve includes a valve portion having a reciprocating valve member and a valve seat opposed to the valve member. A biasing member biases the valve member in one direction and a solenoid applies a drive force to the valve member in an opposite direction. In addition, a hydraulic-pressure-decrease restraining device restrains a decrease of pressure of the brake liquid in the housing.
    Type: Application
    Filed: March 28, 2008
    Publication date: October 2, 2008
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masakuni Suzuki, Tetsuya Miyazaki, Kumiko Akita, Takami Iwamoto
  • Patent number: 7428384
    Abstract: According the invention, a multiplexed light composed of a signal light of a signal wavelength, and a first route control light of a first route control wavelength different from the signal wavelength or a second route control light of a second route control wavelength different from the signal light and the first route control wavelength is incident to a demultiplexer. The demultiplexer demultiplexes the signal light of the signal wavelength, the first route control light, and the second route control light from the multiplexed light. An interferometer optical switch outputs the signal light from first output port according to the first route control light, and outputs the signal light from second output port according to the second route control light.
    Type: Grant
    Filed: December 28, 2004
    Date of Patent: September 23, 2008
    Assignee: National Institute of Information and Communications Technology Incorporated Administrative Agency
    Inventor: Tetsuya Miyazaki
  • Patent number: 7421210
    Abstract: An optical transmitter splits a linear polarization optical carrier into a TE wave and a TM wave. One of the TE wave and the TM wave is phase-modulated with a transmission data so as to generate a phase-modulated signal. The phase-modulated signal and the other one of the TE wave and the TM wave are coupled with a linear polarization and output into an optical transmission line. An optical receiver splits a light input from the optical transmission line into the TE wave and the TM wave. The TM wave or TE wave is converted into the TE wave or TM wave to interfere with the TE wave or TM wave. The interfered signal light is converted into an electric signal for restoration of the data.
    Type: Grant
    Filed: November 30, 2004
    Date of Patent: September 2, 2008
    Assignee: National Institute of Information and Communications Technology Incorporated Administrative Agency
    Inventor: Tetsuya Miyazaki
  • Publication number: 20080179145
    Abstract: An apparatus that generates brake pedal reaction force is provided. The apparatus includes a variable throttle mechanism that varies a fluid passage area between the variable throttle mechanism and a stroke simulator when the flow rate of an operating fluid supplied from a master cylinder exceeds a predetermined flow rate. The variable throttle mechanism includes a movable member, in which a through passage for the operating fluid is formed, and a throttle portion that is formed in the middle of the through passage. The movable member is slidably provided in the inside of a case body and the movable member changes the fluid passage area by closing a portion of a communicating port formed in the case body.
    Type: Application
    Filed: January 16, 2008
    Publication date: July 31, 2008
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Tetsuya Miyazaki, Takahiro Okano
  • Publication number: 20080050124
    Abstract: An optical phase modulation circuit includes an optical phase modulation element, an optical bandpass filter, and an optical directional coupler, wherein control light with a wavelength of ?C is coupled with probe light with a wavelength of ?P using the optical directional coupler and input to the optical phase modulation element, the probe light that has been phase modulated by the optical phase modulation element is extracted through the optical bandpass filter, and the phase of the probe light is modulated in response to the intensity of the control light.
    Type: Application
    Filed: August 22, 2007
    Publication date: February 28, 2008
    Inventors: Hidemi TSUCHIDA, Hiroshi ISHIKAWA, Takashi SHIMOYAMA, Abedin Kazi SARWAR, Tetsuya MIYAZAKI
  • Publication number: 20080010985
    Abstract: A brake system includes a master cylinder that pressurizes hydraulic fluid when a brake control portion is operated; a stroke simulator that, when supplied with the hydraulic fluid pressurized by the master cylinder, produces reactive force in response to the operation of the brake control portion; and a stroke simulator disconnecting mechanism, provided in a hydraulic passage between the master cylinder and the stroke simulator, that mechanically interrupts the flow of the hydraulic fluid through the hydraulic passage when the hydraulic fluid is allowed to flow from the master cylinder to the wheel cylinder in response to the operation of the brake control portion. The stroke simulator disconnecting mechanism starts the disconnecting operation before the hydraulic fluid flows from the master cylinder to the stroke simulator.
    Type: Application
    Filed: June 12, 2007
    Publication date: January 17, 2008
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Tetsuya MIYAZAKI, Takahiro OKANO