Patents by Inventor Jiro Akagi

Jiro Akagi 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: 6390384
    Abstract: The present invention provides a wide range injection timing, small dispersion, good response and simple structure.
    Type: Grant
    Filed: April 12, 1999
    Date of Patent: May 21, 2002
    Assignee: Komatsu Ltd.
    Inventors: Hiroki Sato, Jiro Akagi
  • Patent number: 6256594
    Abstract: Only snapshot data necessary for monitoring faults are collected from machine such as vehicles, allowing faults to be more accurately monitored, and the amount of data and the memory storage volume at a monitoring station to be reduced. The values of a plurality of (A), (B), (C), and (D) operating parameters (engine rotational speed, lever operating position, vehicle speed, and tractive force) which change during the operation of the machine are sequentially detected for each machine. The fault detection history data are thus updated every time a fault (drop in engine oil pressure, overheating) is detected during the operation of the machine.
    Type: Grant
    Filed: August 11, 1998
    Date of Patent: July 3, 2001
    Assignee: Komatsu, Ltd.
    Inventors: Shigeru Yamamoto, Kunihiko Imanishi, Takao Nagai, Sadachika Akiyama, Jiro Akagi, Nobuki Hasegawa, Kazunori Kuromoto, Taku Murakami
  • Patent number: 6209513
    Abstract: An inductive load driving device in which the rise of load current at an initial stage of driving can be executed at high speed includes a plurality of step-up circuits (21, 31), for alternately applying a high voltage to the same inductive load within a predetermined period of time, to thereby allow each load current to rise at a high speed; a holding current output circuit (43), for applying a predetermined voltage to the same inductive load after the load current has risen, to thereby hold the load current at a predetermined value; a plurality of switching means (46, 47), adapted to be switched in such a manner that the respective outputs of the plurality of step-up circuits (21, 31) and the holding current output circuit (43) can be alternately connected to the same inductive load; and a control logic circuit (44), for switching the plurality of switching means (46, 47) in a predetermined sequence.
    Type: Grant
    Filed: December 31, 1998
    Date of Patent: April 3, 2001
    Assignee: Komatsu Ltd.
    Inventors: Takashi Sakasai, Jiro Akagi, Daisuke Yoshida
  • Patent number: 6141629
    Abstract: Maintenance due times of components of a machine are determined according to the status of user-performed in-house maintenance and according to the occurrence of abnormalities during machine operation. A subtraction point (20 points) associated with an abnormality (overheating) detected during machine operation is subtracted from the score (80 points) of a corresponding component (engine) in the machine. An addition point (50 points) associated with the type of maintenance (overhaul performed by in-house maintenance) indicated in maintenance information is added to the score (80 points). Thus, at the time where the value resulting from subtractions from and additions to the score for that component (engine) reaches a prescribed value (10 points) indicating maintenance due time, it is determined that the maintenance due time for that component (engine) has been reached.
    Type: Grant
    Filed: July 13, 1998
    Date of Patent: October 31, 2000
    Assignee: Komatsu Ltd.
    Inventors: Shigeru Yamamoto, Kunihiko Imanishi, Takao Nagai, Sadachika Akiyama, Jiro Akagi, Nobuki Hasegawa, Kazunori Kuromoto, Taku Murakami
  • Patent number: 5842459
    Abstract: The present invention is a method of controlling a fuel injection apparatus for an internal combustion engine, and is capable of preventing the breakage of a component which is exposed to high-temperatures, such as an exhaust manifold. To this end, a first set temperature and a second set temperature, higher than the first set temperature, are set in advance, and a temperature of exhaust gas from an internal combustion engine (1) is detected. The number of occasions at which the temperature of the exhaust gas exceeds the first set temperature and the lengths of time during which the temperature of the exhaust gas has exceeded the second set temperature are totaled respectively, and either when the total number of occasions exceeds a predetermined number of occasions or when the total of the lengths of time exceeds a predetermined length, at least one of the following actions are taken: giving an alarm, reducing a fuel injection rate and changing the injection timing.
    Type: Grant
    Filed: November 20, 1997
    Date of Patent: December 1, 1998
    Assignee: Komatsu Ltd.
    Inventors: Jiro Akagi, Hiroki Sato, Koichi Okaya, Norifumi Abe
  • Patent number: 5785019
    Abstract: A fuel injection system for an internal combustion engine includes a fuel injection pump injecting a fuel in an amount corresponding to a position of a control rack, a governor including a start spring, a control spring and an idling sub-spring biasing the control rack in a fuel injection amount increasing direction, an adjusting lever adjusting a spring load of the control spring, and a fly weight rotating together with the fuel injection pump and shifting the control rack in a fuel injection amount decreasing direction by a centrifugal force, and a stopper mechanism restricting movement of the control rack in the fuel injection amount increasing direction, wherein the stopper mechanism comprising a stopper opposing to an end portion of the control rack and an elastic body biasing and holding the stopper at a stop position, an elastic force of the elastic body being set to be greater than a sum of a spring load of the start spring and a spring load of the idling sub-spring while the adjusting lever is in an
    Type: Grant
    Filed: April 29, 1997
    Date of Patent: July 28, 1998
    Assignee: Komatsu Ltd.
    Inventors: Jiro Akagi, Masaki Takahashi, Hiroki Satow, Godo Ozawa, Noriaki Nakane
  • Patent number: 4561590
    Abstract: A fuel injection nozzle assembly for the injection of fuel under pressure into a combustion chamber of an internal combustion engine. A nozzle body has formed therein a fuel inlet, a storage chamber and spray orifices for discharging pressurized fuel from the storage chamber. Disposed in the storage chamber is a needle valve for opening and closing the spray orifices and a check valve for admitting a metered amount of pressurized fuel into the storage chamber. The needle valve has formed therein a blind hole in which is slidably mounted a stem extending from a cylindrical section of a check valve and an axial passageway is formed through the stem.
    Type: Grant
    Filed: December 28, 1982
    Date of Patent: December 31, 1985
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventor: Jiro Akagi
  • Patent number: 4436247
    Abstract: A diesel fuel injection nozzle and holder assembly includes a tubular nozzle holder carrying a nozzle on one end and defining, in combination therewith, a storage chamber for receiving successive charges of fuel under pressure via a check valve mounted therein. A needle valve, complete with a stem, mounted in the storage chamber is urged by a first spring toward a position for closing spray orifices in the nozzle. Disposed opposite to the end of the needle valve stem, a yieldable abutment is biased by a second spring toward the stem and normally retained a preassigned distance away therefrom. When acted upon by each pressurized fuel charge trapped in the storage chamber, the needle valve is unseated to open the spray orifices against the force of the first spring if the fuel pressure is relatively low, and against the resultant of the forces of the first and second springs if the fuel pressure is higher.
    Type: Grant
    Filed: April 13, 1982
    Date of Patent: March 13, 1984
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventor: Jiro Akagi
  • Patent number: 4367846
    Abstract: An injection valve assembly for spraying fuel into a diesel engine by receiving accurately metered charges of the fuel under pressure from an engine-driven jerk pump. The fuel inlet of the valve assembly communicates via a check valve with a storage chamber, where each incoming charge of pressurized fuel is stored temporarily. The fuel outlet of the valve assembly, in communication with the storage chamber, is normally closed by a spring-biased needle valve member. Upon full accumulation of each fuel charge in the storage chamber the check valve automatically closes the fuel inlet thereby causing the needle valve member to be displaced under the fuel pressure against the bias of the spring and hence to open the fuel outlet. Another embodiment employs two needle valve members, one for the on-off control of communication between the storage chamber and the fuel outlet, and the other for the on-off control of the fuel outlet.
    Type: Grant
    Filed: December 19, 1980
    Date of Patent: January 11, 1983
    Assignee: Kawasaki Steel Corporation
    Inventor: Jiro Akagi
  • Patent number: 4349152
    Abstract: A fuel injection apparatus for a diesel engine comprising a holder body having an accumulator chamber and a spring chamber, a nozzle body detachably connected to the holder body, the nozzle body having formed therein a stepped longitudinal bore, a pressure chamber intermediate the stepped longitudinal bore and an injection orifice communicating with the longitudinal bore, a check valve disposed in a passage communicating a fuel injection pump with the accumulator chamber, a solenoid-operated spool valve mounted in the accumulator chamber, a communication passage having an upper end selectively connectible with the accumulator chamber through the spool valve and a lower end being in constant communication with the pressure chamber, a needle valve fitted in the stepped longitudinal bore and movable therein, and a spring accommodated in the spring chamber for biasing the needle valve toward closing the injection orifice.
    Type: Grant
    Filed: October 2, 1980
    Date of Patent: September 14, 1982
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventor: Jiro Akagi