Patents by Inventor Keiichi Hiki

Keiichi Hiki 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: 6508225
    Abstract: A fuel injected watercraft engine includes a controller for continuing the operation of an electric fuel pump for a predetermined time period after the engine has been stopped. The control system additionally may include a routine for stopping the fuel pump if the lanyard switch is tripped or the watercraft is capsized.
    Type: Grant
    Filed: January 24, 2000
    Date of Patent: January 21, 2003
    Assignee: Yamaha Matsudoki Kabushiki Kaisha
    Inventor: Keiichi Hiki
  • Patent number: 6481394
    Abstract: A two cycle engine includes an exhaust control valve, which opens and closes an exhaust port, and a controller for controlling the exhaust valve. The controller is configured to increase the effective cross-sectional area of the exhaust port when an engine speed increases beyond a specified value and to adjust the amount of fuel injected into the combustion chamber based upon the sensed position of the exhaust control valve. A method for controlling a two-cycle engine is also disclosed. The method comprises determining an engine speed, using the engine speed to determine a target position for an exhaust control valve, moving the exhaust valve towards the target position, sensing a position of the exhaust control valve, and determining a fuel injection amount from at least the sensed position of the exhaust valve and the engine speed.
    Type: Grant
    Filed: September 27, 2000
    Date of Patent: November 19, 2002
    Assignee: Sanshin Kogyo Kabushiki Kaisha
    Inventor: Keiichi Hiki
  • Publication number: 20020115357
    Abstract: A watercraft includes a performance mode selector which enables a rider to select normal operation of the watercraft or an economy mode operation. In the economy mode operation, the watercraft either disables cylinders or reduces fuel injection and ignition in order to limit the maximum engine speed obtained by the engine when the throttle lever is fully depressed Additionally, the watercraft can disable cylinders or selectively reduce fuel injection or ignition when an abnormal operating parameter has been detected.
    Type: Application
    Filed: February 5, 2002
    Publication date: August 22, 2002
    Inventors: Keiichi Hiki, Shigeharu Mineo, Isao Kanno
  • Patent number: 6024068
    Abstract: In accordance with the present invention, there is provided a control for an engine of a watercraft. The watercraft is preferably of the personal variety, and includes a water propulsion device which is driven by an output shaft of the engine. The engine has at least one combustion chamber, an intake system providing air to the combustion chamber, a fuel system providing fuel to the combustion chamber for combustion therein, and an ignition system including at least one ignition element associated with the combustion chamber. The watercraft engine control is of the type which does not include a main switch, but is arranged to turn on electrical systems of the engine when the engine is started and shut them off when the engine is stopped. The control includes a lanyard switch having first and second positions. In a first position the lanyard switch permits power to flow to the ignition element and the electrically-powered engine features, such as a fuel delivery mechanism.
    Type: Grant
    Filed: March 11, 1998
    Date of Patent: February 15, 2000
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Ryoichi Nakase, Shigeyuki Ozawa, Keiichi Hiki
  • Patent number: 5830022
    Abstract: An improved catalytic exhaust system for a watercraft provides two stage treatment of exhaust gases before expulsion from the watercraft. The catalytic exhaust system also is configured to minimize the restriction the catalysts pose to exhaust gas flow through the exhaust system so as to reduce engine back pressure and improve engine performance. A catalytic device of the exhaust system includes a pre catalyst and a main catalyst positioned downstream from the pre catalyst. The pre catalyst can take the from of a catalytic material coating along a portion of the exhaust flow path and the main catalyst can be a catalyst bed. The exhaust gas flow path through the exhaust system also smoothly tapers into and out of the main catalyst so as to reduce the degree of flow resistance through the main catalyst.
    Type: Grant
    Filed: January 24, 1997
    Date of Patent: November 3, 1998
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Ryoichi Nakase, Shigeyuki Ozawa, Keiichi Hiki
  • Patent number: 5797775
    Abstract: A watercraft engine control system for controlling the temperature in the exhaust system to protect against potentially dangerous situations. If the exhaust temperature is sensed to be unduly high, a protective action is initiated. This protective action reduced in the flow of unburned fuel to the exhaust system either stopping of the engine or reducing its speed below idle. The protection action may be initiated either immediately or if the situation occurs for more than a predetermined time period.
    Type: Grant
    Filed: July 1, 1996
    Date of Patent: August 25, 1998
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Shigeyuki Ozawa, Ryoichi Nakase, Keiichi Hiki, Hiroaki Fujimoto
  • Patent number: 5787847
    Abstract: An oil supply system for a watercraft which is powered by an internal combustion engine driving a water propulsion device is disclosed. The system delivers oil to the engine in accordance with a first rate of increase as engine speed increases in a first low engine speed range, and in accordance with a second higher rate of increase as engine speed increases in a second engine speed range higher than the first engine speed range. The lower rate of oil delivery in the first engine speed range is selected to prevent fouling of a catalyst of the engine.
    Type: Grant
    Filed: November 27, 1996
    Date of Patent: August 4, 1998
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Shigeyuki Ozawa, Ryoichi Nakase, Keiichi Hiki
  • Patent number: 5524597
    Abstract: An engine assembly for powering a watercraft that has a front cover which contains a number of electrical components for the engine including the flywheel magneto of the engine, a CDI ignition system for firing the spark plugs and additional components. This permits ease of servicing and reduces the number and length of the interconnecting electrical conduits.
    Type: Grant
    Filed: December 5, 1994
    Date of Patent: June 11, 1996
    Assignee: Sanshin Kogyo Kabushiki Kaisha
    Inventors: Keiichi Hiki, Naoki Katoh, Ryoichi Nakase