Patents by Inventor Mitsuyo Nishikawa

Mitsuyo Nishikawa 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: 5408607
    Abstract: An information transfer system in which an information transfer control arrangement including information transfer control and reference information storage is provided in a system having at least three subsystems communicating with each other using transfer information which contains an information unit common to all information handled by the subsystems. The information transfer control refers to information in the reference information storage, and rearranges the information arrangement from the transferer subsystem to an information arrangement suitable for the transferee subsystem, if necessary, followed by transferring it. The subsystem can be changed easily by adding, deleting or correcting the reference information in the reference information storage. The configuration of the transfer control system is therefore flexible.
    Type: Grant
    Filed: March 19, 1991
    Date of Patent: April 18, 1995
    Assignee: Hitachi, ltd.
    Inventors: Mitsuyo Nishikawa, Hiromi Inaba, Kiyoshi Nakamura, Takashi Kaneko, Tokio Maebara
  • Patent number: 4756684
    Abstract: A monitor method for the combustion conditions in a furnace of a boiler having a plurality of burners is disclosed. The method includes the steps of detecting the flame intensity at a predetermined position of a flame, by using an optical fiber having as its view the predetermined position at the flame of each of the plurality of burners; judging if the combustion conditions of each burner are normal or not, based on if the flame intensity detected for each burner flame is within a predetermined normal level range; and displaying the judgement results. Preferably, an image fiber for obtaining a flame image indicating the combustion conditions is provided for at least one of the burners, and the normal level range is determined based on the flame image obtained by the image fiber.
    Type: Grant
    Filed: April 9, 1987
    Date of Patent: July 12, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Mitsuyo Nishikawa, Tooru Kimura, Akira Fukuhara
  • Patent number: 4622922
    Abstract: A combustion control method wherein manipulated variables or the amounts of fuel and air in at least one combustion zone of a boiler are regulated so that both the amount of nitrogen oxides and the amount of unburned coal in the ash at an outlet of a burner furnace or at least one of them passes the regulation standards and satisfies the requirements for operating a plant.
    Type: Grant
    Filed: June 10, 1985
    Date of Patent: November 18, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Hisanori Miyagaki, Toshihiko Higashi, Atsushi Yokogawa, Yoshihiro Shimada, Nobuo Kurihara, Mitsuyo Nishikawa, Yoshio Sato, Atsumi Watanabe, Yasuo Morooka
  • Patent number: 4620491
    Abstract: This invention relates to the supervision of a combustion state of a combustion furnace. A flame formed concentrically with the direction of a fuel jetted from a burner being the center is measured from its side, and two oxidizing flame zones as high luminance zones are extracted. Using the shape parameters of the flame, an index for reducing NOx and unburnt components in ash are calculated and estimated so as to supervise the combustion state. The positions or centroids of the flames and the distance between the centroids are used as the shape parameters, and the flame shape is divided into two zones for easy display of each zone.
    Type: Grant
    Filed: April 23, 1985
    Date of Patent: November 4, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Mitsuyo Nishikawa, Nobuo Kurihara, Yoshio Sato, Atsumi Watanabe, Toshihiko Higashi, Hisanori Miyagaki, Atsushi Yokogawa, Yoshihiro Shimada
  • Patent number: 4555800
    Abstract: A method of diagnosing a combustion state in a furnace of a boiler wherein the shape of the root part of a flame (namely, the part closer to the fuel jet port of a burner) is picked up by an image sensor or the like, and the combustion state is diagnosed from the shape. Concretely, the relationships between the shapes of the root parts of flames and the combustion states of the furnace, e.g., the amount of CO or the amount of NOx are experimentally or empirically ensured and are stored in advance, one of the patterns of the stored flame shapes is selected on the basis of the shape of the root part of the flame actually observed, and the combustion state of the furnace is judged the combustion state of the selected flame shape.
    Type: Grant
    Filed: August 30, 1983
    Date of Patent: November 26, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Mitsuyo Nishikawa, Nobuo Kurihara
  • Patent number: 4528918
    Abstract: A method of controlling combustion in a furnace of a boiler or the like having a burner for a main combustion and a burner for a reducing combustion in order to effect combustion for furnace denitrification. The method comprises the steps of: estimating the NO.sub.x generation amount from data on a flame formed by the main combustion; estimating the reducing agent generation amount from data on a flame formed by the reducing combustion; and controlling the flow rates of fuel and air supplied for the main and reducing combustions so that the amount of NO.sub.x emission as the difference between the NO.sub.x generation amount and the reducing agent generation amount is below a specified value. In practice, each of the NO.sub.x generation amount and the reducing agent generation amount is estimated from the flame pattern, the flame volume, the distance between the outlet of the burner concerned and the root of the flame concerned, etc.
    Type: Grant
    Filed: April 18, 1984
    Date of Patent: July 16, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Yoshio Sato, Nobuo Kurihara, Hiroshi Matsumoto, Tadayoshi Saito, Mitsuyo Nishikawa, Toshihiko Higashi
  • Patent number: 4437163
    Abstract: A method of symptom diagnosis by continuously detecting vibration of the shaft of a rotary machine and monitoring a signal indicative of detected shaft vibration for the diagnosis of the operating condition of the rotary machine. In the method, a symptom of unusual operation of the rotary machine is diagnosed. The rotation speed range of the rotary machine is classified into a safety region, an alarm region and a trip region depending on the level of the shaft vibration signal. According to the disclosed method, symptom diagnostic regions are established within the safety region at time intervals of a symptom diagnostic period, and whether or not the level of the detected shaft vibration signal deviates from that of the symptom diagnostic regions is continuously monitored for the diagnosis of a symptom of unusual operation of the rotary machine.
    Type: Grant
    Filed: March 30, 1981
    Date of Patent: March 13, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Nobuo Kurihara, Yasuo Morooka, Mitsuyo Nishikawa, Kiyoshi Miura, Yoshitoshi Nagahashi
  • Patent number: 4426641
    Abstract: From the viewpoint of the preventive maintenance operation of a rotary machine, it is a very important subject to monitor the shaft vibration of the rotary machine and grasp the operating state of the machine. This invention relates to input processings in the case of executing the frequency analysis of a shaft vibration signal by digital processings.This invention describes the rotational frequency synchronization of a sampling frequency, the phase synchronization of the rotary machine to a reference phase, the relationship between an analytical wave number and a sample nunber, etc. in that case.
    Type: Grant
    Filed: March 31, 1981
    Date of Patent: January 17, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Nobuo Kurihara, Yasuo Morooka, Mitsuyo Nishikawa, Kiyoshi Miura, Yoshitoshi Nagahashi
  • Patent number: 4352293
    Abstract: In a rotary machine mounted on a rotary shaft journaled in journal bearings, a source of unusual vibration of the rotary machine is identified on the basis of the results of the steps of (1) subjecting a shaft vibration signal to frequency analysis for analyzing its frequency distribution, and (2) analyzing the amplitude of the shaft vibration signal and the variation rate of a phase signal of a component related to the shaft rotation frequency among the frequency components of the shaft vibration signal. The present invention is usefully applicable to diagnosis of vibration of a rotary shaft of a large-size turbine or a generator in a power plant by continuously monitoring the shaft vibration for immediately automatically detecting unusual vibration of the rotary machine in the event of occurrence of such unusual vibration.
    Type: Grant
    Filed: August 25, 1980
    Date of Patent: October 5, 1982
    Assignee: Hitachi, Ltd.
    Inventors: Nobuo Kurihara, Mitsuyo Nishikawa, Yoshitoshi Nagahashi, Masafumi Takechi
  • Patent number: 4302813
    Abstract: The present invention relates to a method of controlling the operation of large rotary machines such as steam turbines and generators in a thermal power plant or nuclear power plant. More specifically, the invention relates to a method of controlling such operation as increasing or decreasing the speed of the rotary machines or stopping the operation of the rotary machines, by detecting vibration at the time of starting the operation or during the steady-speed operation, by analyzing the detected vibration signals to determine whether the operation is in normal condition or abnormal condition, and by detecting or forecasting the cause in case the operation is in abnormal condition.
    Type: Grant
    Filed: February 22, 1979
    Date of Patent: November 24, 1981
    Assignee: Hitachi, Ltd.
    Inventors: Nobuo Kurihara, Mitsuyo Nishikawa, Shigeyoshi Kawano