Patents by Inventor Hiraku Ohba

Hiraku Ohba 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: 5979397
    Abstract: The present invention aims at preventing such a situation that anyone of the divided injection amounts becomes less than a minimum compensation amount for a fuel injection valve, in case of conducting a two-step injection (weakly stratified combustion) in which a part of fuel is injected during intake stroke and the remaining fuel is injected during compression stroke. To this end, at the time of instructing to conduct the two-step injection, a whole injection amount TI is divided into: an injection amount TIH for homogeneous combustion to be injected during intake stroke, and an injection amount TIS for stratified combustion to be injected during compression stroke, based on a division ratio corresponding to a target air-fuel ratio. Further, each of the injection amounts TIH and TIS after division is compared with a minimum compensation amount MIN for the fuel injection valve.
    Type: Grant
    Filed: June 30, 1998
    Date of Patent: November 9, 1999
    Assignee: Unisia Jecs Corporation
    Inventors: Kenichi Machida, Junichi Furuya, Hiraku Ohba, Yuki Nakajima, Takamasa Ueda
  • Patent number: 5970950
    Abstract: In the control method and apparatus of a direct injection gasoline engine, as for the uniform charge combustion mode performing only the intake stroke injection and the stratified charge combustion mode performing only the compression stroke injection, the injection timing is determined by referring to the injection timing map set for each mode. On the other hand, in the double injection mode performing the intake stroke injection and the compression stroke injection, the injection timing map for the intake stroke injection and the injection timing map for the compression stroke injection are both equipped, and the injection timing in the intake stroke injection is determined by the fuel quantity being injected by the intake stroke, and the injection timing in the compression stroke injection is determined by the fuel quantity being injected by the compression stroke.
    Type: Grant
    Filed: June 29, 1998
    Date of Patent: October 26, 1999
    Assignee: Unisia Jecs Corporation
    Inventors: Hirokazu Shimizu, Hajime Hosoya, Hiraku Ohba, Yuki Nakajima, Takamasa Ueda
  • Patent number: 5615660
    Abstract: A warmup fuel amount corresponding to a predetermined heavy fuel is set to control an air-fuel ratio of an air-fuel mixture supplied to an engine during warmup. A correction amount based on a difference between a post-warmup engine speed variation and a first reference value is stored, and a warmup fuel amount decreased by this correction is supplied to the engine on the next startup occasion. In this way the sensitivity of air-fuel ratio control during startup when fuels of different nature are used, is enhanced.
    Type: Grant
    Filed: March 5, 1996
    Date of Patent: April 1, 1997
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Hiroshi Iwano, Hiraku Ohba