Patents by Inventor Hideo Sawaoka

Hideo Sawaoka 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: 10023055
    Abstract: A rotational speed command output unit receives and outputs a command value of a motor rotational speed inputted from outside. A PWM duty calculator calculates a PWM duty based on the command value and an actual rotational speed of a motor. A maximum speed estimator estimates, based on the actual rotational speed measured, a parameter representing a controlled state of the motor, a current PWM duty and a predetermined upper limit of the PWM duty, a maximum rotational speed of the motor to be reached under PWM control with the upper limit of the PWM duty. The command value inputted from outside is restricted not to exceed the maximum rotational speed. In this way, when a motor is PWM-controlled, abrupt changes in the rotational speed of the motor due to supply voltage fluctuations can be suppressed.
    Type: Grant
    Filed: September 14, 2015
    Date of Patent: July 17, 2018
    Assignee: DENSO CORPORATION
    Inventor: Hideo Sawaoka
  • Publication number: 20170274781
    Abstract: A rotational speed command output unit receives and outputs a command value of a motor rotational speed inputted from outside. A PWM duty calculator calculates a PWM duty based on the command value and an actual rotational speed of a motor. A maximum speed estimator estimates, based on the actual rotational speed measured, a parameter representing a controlled state of the motor, a current PWM duty and a predetermined upper limit of the PWM duty, a maximum rotational speed of the motor to be reached under PWM control with the upper limit of the PWM duty. The command value inputted from outside is restricted not to exceed the maximum rotational speed. In this way, when a motor is PWM-controlled, abrupt changes in the rotational speed of the motor due to supply voltage fluctuations can be suppressed.
    Type: Application
    Filed: September 14, 2015
    Publication date: September 28, 2017
    Inventor: Hideo SAWAOKA
  • Patent number: 8467441
    Abstract: In a PWM communication system, a sensor unit transmits as reference pulses transmission signals, which exhibit duty cycles of 100% and 0%, respectively, prior to transmission of a transmission signal, which has data items compressed thereinto by a signal processing circuit. An input capture circuit of an ECU measures the duty time and the PWM cycle of the transmission signal according to a timer clock of a timer circuit. A signal processing circuit of the ECU produces a duty cycle correction factor k based on the measured duty times and PWM cycles of the reference pulses, produces receiving data based on the duty time and the PWM cycle of the transmission signal, and the duty cycle correction factor, and separates the receiving data into sensor output values of a pressure sensor and a temperature sensor.
    Type: Grant
    Filed: June 10, 2011
    Date of Patent: June 18, 2013
    Assignee: DENSO CORPORATION
    Inventors: Hideo Sawaoka, Yasuaki Makino, Toshihiko Matsuoka
  • Publication number: 20110310954
    Abstract: In a PWM communication system, a sensor unit transmits as reference pulses transmission signals, which exhibit duty cycles of 100% and 0%, respectively, prior to transmission of a transmission signal, which has data items compressed thereinto by a signal processing circuit. An input capture circuit of an ECU measures the duty time and the PWM cycle of the transmission signal according to a timer clock of a timer circuit. A signal processing circuit of the ECU produces a duty cycle correction factor k based on the measured duty times and PWM cycles of the reference pulses, produces receiving data based on the duty time and the PWM cycle of the transmission signal, and the duty cycle correction factor, and separates the receiving data into sensor output values of a pressure sensor and a temperature sensor.
    Type: Application
    Filed: June 10, 2011
    Publication date: December 22, 2011
    Applicant: DENSO CORPORATION
    Inventors: Hideo Sawaoka, Yasuaki Makino, Toshihiko Matsuoka
  • Patent number: 7117081
    Abstract: An evaluation system for a fault diagnosis function has an engine ECU. The ECU is connected to an engine, sensors, and a MIL. The ECU diagnoses the sensors. The ECU also determines whether a diagnosis process of the diagnosis function for the sensors is completed. A memory stores a plurality of the completion result. When at least one of the diagnosis processes is completed in the last ten completion result, it is determined that the diagnosis function is in a normal condition. Otherwise, it is determined that the diagnosis function is in an abnormal condition, and the MIL indicates the abnormal condition.
    Type: Grant
    Filed: October 20, 2003
    Date of Patent: October 3, 2006
    Assignee: DENSO Corporation
    Inventor: Hideo Sawaoka
  • Publication number: 20040083071
    Abstract: An evaluation system for a fault diagnosis function has an engine ECU. The ECU is connected to an engine, sensors, and a MIL. The ECU diagnoses the sensors. The ECU also determines whether a diagnosis process of the diagnosis function for the sensors is completed. A memory stores a plurality of the completion result. When at least one of the diagnosis processes is completed in the last ten completion result, it is determined that the diagnosis function is in a normal condition. Otherwise, it is determined that the diagnosis function is in an abnormal condition, and the MIL indicates the abnormal condition.
    Type: Application
    Filed: October 20, 2003
    Publication date: April 29, 2004
    Applicant: Denso Corporation
    Inventor: Hideo Sawaoka