Patents by Inventor Tadashi Kawahara

Tadashi Kawahara 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: 11352048
    Abstract: A rotation detection device includes a rotation detection circuit, a step-up power supply circuit, a step-down power supply circuit, a first power supply path, and a second power supply path. The rotation detection circuit is configured to detect a rotation number of a motor that generates a torque applied to a steering mechanism of a vehicle, based on an electric signal. The electric signal is generated according to a rotation angle of the motor that is acquired through an in-vehicle sensor.
    Type: Grant
    Filed: September 23, 2019
    Date of Patent: June 7, 2022
    Assignees: JTEKT CORPORATION, RENESAS ELECTRONICS CORPORATION
    Inventors: Kenichi Kozuka, Masato Oda, Tadashi Kawahara, Masashi Oki
  • Patent number: 11105270
    Abstract: A control device for a rotary machine, which is driven by a turbine output torque which is an output of a turbine and an electric motor output torque which is an output of an induction motor, includes: a required output setting unit configured to set a required torque for driving the rotary machine; and a drive source command unit configured to set the electric motor output torque to a minimum torque or higher of the induction motor and to set the turbine output torque to a value obtained by subtracting the electric motor output torque from the required torque when the turbine output torque is greater than or equal to a lower limit in a stable output range of the turbine.
    Type: Grant
    Filed: September 27, 2016
    Date of Patent: August 31, 2021
    Assignee: MITSUBISHI HEAVY INDUSTRIES COMPRESSOR CORPORATION
    Inventors: Tadashi Kawahara, Yoshiyuki Okamoto
  • Publication number: 20200102001
    Abstract: A rotation detection device includes a rotation detection circuit, a step-up power supply circuit, a step-down power supply circuit, a first power supply path, and a second power supply path. The rotation detection circuit is configured to detect a rotation number of a motor that generates a torque applied to a steering mechanism of a vehicle, based on an electric signal. The electric signal is generated according to a rotation angle of the motor that is acquired through an in-vehicle sensor.
    Type: Application
    Filed: September 23, 2019
    Publication date: April 2, 2020
    Applicants: JTEKT CORPORATION, RENESAS ELECTRONICS CORPORATION
    Inventors: Kenichi KOZUKA, Masato ODA, Tadashi KAWAHARA, Masashi OKI
  • Publication number: 20190264692
    Abstract: A control device for a rotary machine, which is driven by a turbine output torque which is an output of a turbine and an electric motor output torque which is an output of an induction motor, includes: a required output setting unit configured to set a required torque for driving the rotary machine; and a drive source command unit configured to set the electric motor output torque to a minimum torque or higher of the induction motor and to set the turbine output torque to a value obtained by subtracting the electric motor output torque from the required torque when the turbine output torque is greater than or equal to a lower limit in a stable output range of the turbine.
    Type: Application
    Filed: September 27, 2016
    Publication date: August 29, 2019
    Applicant: MITSUBISHI HEAVY INDUSTRIES COMPRESSOR CORPORATION
    Inventors: Tadashi Kawahara, Yoshiyuki Okamoto
  • Patent number: 6829318
    Abstract: A phase locked loop (PLL) frequency synthesizer has a phase comparator, a voltage-controlled oscillator, a charge pump circuit, a loop filter, a variable frequency divider periodically changing a division value in response to a frequency division value changing circuit, and a charge pump bias circuit for supplying a modulated reference bias current, for canceling a phase error, to the charge pump circuit. As a result, without generating additional spurious components, conventionally-generated spurious components can be suppressed.
    Type: Grant
    Filed: June 22, 2001
    Date of Patent: December 7, 2004
    Assignees: Renesas Technology Corp., Mitsubishi Electric Engineering Co., Ltd.
    Inventor: Tadashi Kawahara
  • Patent number: 6734739
    Abstract: The phase comparator in a phase locked loop synthesizer has a identical first and second transmission gates connected to a front row and a back row of 2N−1 gate delay elements, respectively. Third and fourth transmission gates are permanently set to an ON setting. The first transmission gate and NAND gates operate as a gate delay element when a COUNT signal is at a low logical level and operate as a ring oscillator when the COUNT signal is at a high logical level.
    Type: Grant
    Filed: October 30, 2002
    Date of Patent: May 11, 2004
    Assignee: Mitsubishikdenki Kabushiki Kaisha
    Inventor: Tadashi Kawahara
  • Publication number: 20030222723
    Abstract: The phase comparator in the PLL synthesizer has first and second transmission gates of identical shape connected to the front and back row of 2N−1 gate delay elements. Third and fourth transmission gates are permanently set to ON setting. The first transmission gate and the NAND gates operate as a gate delay element when the COUNT signal is of low logical level and operate as a ring oscillator when the COUNT signal is of high logical level.
    Type: Application
    Filed: October 30, 2002
    Publication date: December 4, 2003
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Tadashi Kawahara
  • Patent number: 6622680
    Abstract: An opening long in the longitudinal direction of a duct wall is formed. The whole of the opening is covered with non-woven fabric, and the lateral width of the opening is set to be not shorter than {fraction (1/20)} of the circumferential length of the duct wall. Alternatively, a porous member is thermally welded with the head of an opening of a small cylindrical portion projecting from the duct wall of a duct body 1, while the duct body is prevented from deformation. In a method for manufacturing the air take duct, a high-melting molded piece is brought into contact with a hot plate so as to be heated. A low-melting molded piece is disposed at a distance from the hot plate so as to be heated by radiation heat from the hot plate.
    Type: Grant
    Filed: May 17, 2001
    Date of Patent: September 23, 2003
    Assignee: Toyoda Gosei Co., Ltd.
    Inventors: Hitoshi Kino, Yutaka Ogasawara, Shinji Ito, Yoshikazu Hirose, Takahiro Komori, Tadashi Kawahara
  • Publication number: 20030062013
    Abstract: An opening long in the longitudinal direction of a duct wall is formed. The whole of the opening is covered with non-woven fabric, and the lateral width of the opening is set to be not shorter than {fraction (1/20)} of the circumferential length of the duct wall. Alternatively, a porous member is thermally welded with the head of an opening of a small cylindrical portion projecting from the duct wall of a duct body 1, while the duct body is prevented from deformation. In a method for manufacturing the air take duct, a high-melting molded piece is brought into contact with a hot plate so as to be heated. A low-melting molded piece is disposed at a distance from the hot plate so as to be heated by radiation heat from the hot plate.
    Type: Application
    Filed: May 17, 2001
    Publication date: April 3, 2003
    Applicant: Toyoda Gosei Co., Ltd.
    Inventors: Hitoshi Kino, Yutaka Ogasawara, Shinji Ito, Yoshikazu Hirose, Takahiro Komori, Tadashi Kawahara
  • Publication number: 20020097825
    Abstract: The PLL frequency synthesizer has a phase comparator, a voltage-controlled oscillator, a charge pump circuit, a loop filter, a variable frequency divider capable of periodically changing a division value by a frequency division value changing circuit, and a charge pump bias circuit for supplying a modulation reference bias current for canceling a phase error amount to the charge pump circuit. As a result, without generating other spurious components by the configuration, conventionally-generated spurious components can be suppressed.
    Type: Application
    Filed: June 22, 2001
    Publication date: July 25, 2002
    Inventor: Tadashi Kawahara
  • Patent number: 6044255
    Abstract: A radio frequency circuit is disclosed which includes a low-noise amplifier and a mixer integrated on the same semiconductor chip by using a silicon BiCMOS process. The low-noise amplifier has a silicon bipolar junction transistor and the mixer has a silicon MOS type field effect transistor. In the radio frequency circuit, the mixer can include two silicon MOS type field effect transistors one of which has a source connected to a drain of the other silicon MOS type field effect transistor and a gate of one silicon MOS type field effect transistor is supplied with a local signal and a gate of the other silicon MOS type field effect transistor is supplied with a radio frequency signal amplified by the low-noise amplifier.
    Type: Grant
    Filed: September 29, 1997
    Date of Patent: March 28, 2000
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Noriharu Suematsu, Masayoshi Ono, Tadashi Kawahara, Mikio Uesugi, Kenji Hiroshige, Yoshitada Iyama
  • Patent number: 6005441
    Abstract: An amplifying circuit has a feedback reactance element connected across a biasing feedback resistor and an input terminal for suppressing feedback of thermal noise generated by the biasing feedback resistor.
    Type: Grant
    Filed: May 26, 1998
    Date of Patent: December 21, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Tadashi Kawahara
  • Patent number: 5625282
    Abstract: The present invention provides a constant current circuit for suppressing operation of parasitic thyristor and for preventing short-circuit of IC, even if high voltage such as a thunder is applied to a power source which increases a power supply potential Vcc momentarily. A constant current circuit of the present invention comprises a first current mirror circuit having a first pair of transistors, a second current mirror circuit having a second pair of transistors, and a MOS type capacitor being connected between the collector electrodes of said first pair of transistors and being formed in a second well area of the semiconductor substrate which is adjacent to the first well area where the first and the second mirror circuits are formed thereon.
    Type: Grant
    Filed: February 9, 1996
    Date of Patent: April 29, 1997
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Tadashi Kawahara