Patents by Inventor Toshiaki Oyama

Toshiaki Oyama 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: 9806643
    Abstract: The present invention relates to a drive control apparatus for an electric motor and a control method thereof. In the present invention, the generation of electric brake is suppressed while protecting a semiconductor relay from excessive surge voltage. The drive control apparatus is configured to include: a drive circuit for controlling the drive of the electric motor; a semiconductor relay arranged on a drive line between the drive circuit and the electric motor to cut off current supply from the drive circuit to the electric motor; and an active clamp circuit for turning on the semiconductor relay when a potential difference between the drive circuit side and the electric motor side of the semiconductor relay is greater than or equal to a predetermined value.
    Type: Grant
    Filed: March 17, 2014
    Date of Patent: October 31, 2017
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Toshiaki Oyama, Tomonobu Koseki, Tomishige Yatsugi
  • Publication number: 20160181953
    Abstract: The present invention relates to a drive control apparatus for an electric motor and a control method thereof. In the present invention, the generation of electric brake is suppressed while protecting a semiconductor relay from excessive surge voltage. The drive control apparatus is configured to include: a drive circuit for controlling the drive of the electric motor; a semiconductor relay arranged on a drive line between the drive circuit and the electric motor to cut off current supply from the drive circuit to the electric motor; and an active clamp circuit for turning on the semiconductor relay when a potential difference between the drive circuit side and the electric motor side of the semiconductor relay is greater than or equal to a predetermined value.
    Type: Application
    Filed: March 17, 2014
    Publication date: June 23, 2016
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Toshiaki OYAMA, Tomonobu KOSEKI, Tomishige YATSUGI
  • Publication number: 20160028336
    Abstract: A control apparatus for an electric motor has a drive circuit that drives the electric motor in which a plurality of phase coils are star-connected, a neutral point drive circuit connected to a neutral point of the star connection, semiconductor relays that cut off an electric path connecting the neutral point and the neutral point drive circuit, and a microcomputer. Furthermore, the microcomputer cuts off the electric path by the semiconductor relays when it is possible to normally drive the electric motor by the drive circuit.
    Type: Application
    Filed: July 10, 2014
    Publication date: January 28, 2016
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Toshiaki OYAMA, Tomonobu KOSEKI
  • Publication number: 20150249406
    Abstract: The present invention relates to a driving device for an electric motor, including an inverter circuit and a power-supply relay disposed in a power-supply line of the inverter circuit, the power-supply relay including a semiconductor switch, and relates to a driving method therefor. The driving device of the present invention includes a first driver and a second driver that drive the power-supply relay, and when at least one of the first driver and the second driver outputs an ON signal, the power-supply relay is turned ON. This can reduce the disruption of power-supplying to the inverter circuit due to a failure in a driver.
    Type: Application
    Filed: July 10, 2014
    Publication date: September 3, 2015
    Inventors: Tomonobu Koseki, Toshiaki Oyama