Patents by Inventor Eri KISHIMOTO

Eri KISHIMOTO 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).

  • Driving apparatus for sensorless fan motor
    Patent number: 8729839
    Abstract: A BEMF detection circuit generates a rotation detection signal indicating a comparison result between electromotive force voltages VU through VW which occur at a terminal of respective multiple coils and an intermediate-point voltage VCOM. A rotor position detection circuit generates a rotor position detection signal indicating a stopped rotor position An internal start-up synchronization signal generating unit generates a predetermined-frequency forced synchronization signal. Upon receiving a fan motor start-up instruction, a driving signal synthesizing circuit generates a driving control signal based upon the rotor position detection signal. Thus, (1) when back electromotive force voltage occurs, a sensorless driving operation is started based upon the rotation detection signal; (2) when it does not occur, the driving control signal is generated based upon the forced synchronization signal. Subsequently, when it occurs, the sensorless driving operation is started based upon the rotation detection signal.
    Type: Grant
    Filed: October 25, 2011
    Date of Patent: May 20, 2014
    Assignee: Rohm Co., Ltd.
    Inventors: Toshiya Suzuki, Shinsuke Sano, Atsushi Sato, Eri Kishimoto
  • DRIVING APPARATUS FOR SENSORLESS FAN MOTOR
    Publication number: 20120106072
    Abstract: A BEMF detection circuit generates a rotation detection signal indicating a comparison result between electromotive force voltages VU through VW which occur at a terminal of respective multiple coils and an intermediate-point voltage VCOM. A rotor position detection circuit generates a rotor position detection signal indicating a stopped rotor position An internal start-up synchronization signal generating unit generates a predetermined-frequency forced synchronization signal. Upon receiving a fan motor start-up instruction, a driving signal synthesizing circuit generates a driving control signal based upon the rotor position detection signal. Thus, (1) when back electromotive force voltage occurs, a sensorless driving operation is started based upon the rotation detection signal; (2) when it does not occur, the driving control signal is generated based upon the forced synchronization signal. Subsequently, when it occurs, the sensorless driving operation is started based upon the rotation detection signal.
    Type: Application
    Filed: October 25, 2011
    Publication date: May 3, 2012
    Applicant: ROHM CO., LTD.
    Inventors: Toshiya SUZUKI, Shinsuke SANO, Atsushi SATO, Eri KISHIMOTO