Patents by Inventor Kiyoharu Nakao

Kiyoharu Nakao 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).

  • Publication number: 20090140678
    Abstract: A torque ripple suppressor (50) includes: an SR motor (20) coupled to an engine; a rotary position detector (24) that detects a rotary position of the SR motor (20); a pulse interval calculator (41) that calculates output interval of pulses output from the pulse interval calculator (24); an average pulse interval calculator (42) that calculates the average of calculated value of the pulse interval calculator (41); a pulse output state judging section (44) that judges whether the calculated value of the pulse interval calculator (41) is wider than the calculated vale of the average pulse interval calculator (42) or not, and a current controller (48) that controls motoring current or generating current of the SR motor (20) based on judgment of the pulse output state judging section (44).
    Type: Application
    Filed: July 20, 2006
    Publication date: June 4, 2009
    Inventor: Kiyoharu Nakao
  • Patent number: 7499482
    Abstract: An injection locking type or MOPA type of laser device capable of always providing stable output energy and wavelength is provided. For this purpose, the laser device includes an oscillator for exciting laser gas by oscillator discharge and oscillating seed laser light with band-narrowed wavelength, an amplifier for amplifying the seed laser light by amplification discharge to emit amplified laser light, a delay circuit for setting at least one of a delay time from light emission of the seed laser light to light emission of the amplified laser light, and a delay time from start of the oscillator discharge to start of the aforementioned amplification discharge, and a delay time compensation circuit for performing compensation of the delay circuit so that the delay time becomes an optimal delay time.
    Type: Grant
    Filed: June 19, 2006
    Date of Patent: March 3, 2009
    Assignee: Komatsu Ltd.
    Inventors: Kiyoharu Nakao, Yoshifumi Ueno
  • Patent number: 7230966
    Abstract: An injection locking type or MOPA type of laser device capable of always providing stable output energy and wavelength is provided. For this purpose, the laser device includes an oscillator for exciting laser gas by oscillator discharge and oscillating seed laser light with band-narrowed wavelength, an amplifier for amplifying the seed laser light by amplification discharge to emit amplified laser light, a delay circuit for setting at least one of a delay time from light emission of the seed laser light to light emission of the amplified laser light, and a delay time from start of the oscillator discharge to start of the aforementioned amplification discharge, and a delay time compensation circuit for performing compensation of the delay circuit so that the delay time becomes an optimal delay time.
    Type: Grant
    Filed: August 29, 2005
    Date of Patent: June 12, 2007
    Assignee: Komatsu, Ltd.
    Inventors: Kiyoharu Nakao, Yoshifumi Ueno
  • Publication number: 20060239307
    Abstract: An injection locking type or MOPA type of laser device capable of always providing stable output energy and wavelength is provided. For this purpose, the laser device includes an oscillator for exciting laser gas by oscillator discharge and oscillating seed laser light with band-narrowed wavelength, an amplifier for amplifying the seed laser light by amplification discharge to emit amplified laser light, a delay circuit for setting at least one of a delay time from light emission of the seed laser light to light emission of the amplified laser light, and a delay time from start of the oscillator discharge to start of the aforementioned amplification discharge, and a delay time compensation circuit for performing compensation of the delay circuit so that the delay time becomes an optimal delay time.
    Type: Application
    Filed: June 19, 2006
    Publication date: October 26, 2006
    Inventors: Kiyoharu Nakao, Yoshifumi Ueno
  • Patent number: 7095773
    Abstract: An injection locking type or MOPA type of laser device capable of always providing stable output energy and wavelength is provided. For this purpose, the laser device includes an oscillator for exciting laser gas by oscillator discharge and oscillating seed laser light with band-narrowed wavelength, an amplifier for amplifying the seed laser light by amplification discharge to emit amplified laser light, a delay circuit for setting at least one of a delay time from light emission of the seed laser light to light emission of the amplified laser light, and a delay time from start of the oscillator discharge to start of the aforementioned amplification discharge, and a delay time compensation circuit for performing compensation of the delay circuit so that the delay time becomes an optimal delay time.
    Type: Grant
    Filed: March 12, 2002
    Date of Patent: August 22, 2006
    Assignee: Komatsu Ltd.
    Inventors: Kiyoharu Nakao, Yoshifumi Ueno
  • Publication number: 20050281306
    Abstract: An injection locking type or MOPA type of laser device capable of always providing stable output energy and wavelength is provided. For this purpose, the laser device includes an oscillator for exciting laser gas by oscillator discharge and oscillating seed laser light with band-narrowed wavelength, an amplifier for amplifying the seed laser light by amplification discharge to emit amplified laser light, a delay circuit for setting at least one of a delay time from light emission of the seed laser light to light emission of the amplified laser light, and a delay time from start of the oscillator discharge to start of the aforementioned amplification discharge, and a delay time compensation circuit for performing compensation of the delay circuit so that the delay time becomes an optimal delay time.
    Type: Application
    Filed: August 29, 2005
    Publication date: December 22, 2005
    Inventors: Kiyoharu Nakao, Yoshifumi Ueno
  • Patent number: 6937634
    Abstract: An injection locking type or MOPA type of laser device capable of always providing stable output energy and wavelength is provided. For this purpose, the laser device includes an oscillator for exciting laser gas by oscillator discharge and oscillating seed laser light with band-narrowed wavelength, an amplifier for amplifying the seed laser light by amplification discharge to emit amplified laser light, a delay circuit for setting at least one of a delay time from light emission of the seed laser light to light emission of the amplified laser light, and a delay time from start of the oscillator discharge to start of the aforementioned amplification discharge, and a delay time compensation circuit for performing compensation of the delay circuit so that the delay time becomes an optimal delay time.
    Type: Grant
    Filed: March 12, 2002
    Date of Patent: August 30, 2005
    Assignee: Komatsu Ltd.
    Inventors: Kiyoharu Nakao, Yoshifumi Ueno
  • Patent number: 6798803
    Abstract: In a gas laser device, a compensation time according to electric charges accumulated in a charging capacitor is calculated and, when the compensation time lapsed from a time when an outer trigger was input, a compensation trigger is output to a semiconductor switch to electrically connect the charging capacitor and a first-stage capacitor, whereby a time between the input of the outer trigger and the occurrence of light emission across discharge electrodes becomes constant in each pulse and a semiconductor substrate can be exposed to light with higher accuracy even when any components of a pulse power source are affected by a temperature change.
    Type: Grant
    Filed: November 21, 2002
    Date of Patent: September 28, 2004
    Assignee: Komatsu Ltd.
    Inventor: Kiyoharu Nakao
  • Patent number: 6721344
    Abstract: An injection locking type or MOPA type of laser device capable of always obtaining stable output energy and wavelength is provided. For this purpose, the laser device includes an oscillator (11A) for oscillating seed laser light (21A) with wavelength band-narrowed by a band-narrowing unit (30), an amplifier (11B) for amplifying the seed laser light and emitting the amplified laser light (21B), a wavelength monitor (34A) for detecting at least a wavelength characteristic of the seed laser light, and a laser controller (29) for performing adjustment oscillation to contain a wavelength characteristic within a predetermined allowable range, at a time of startup or when laser oscillation is suspended for a predetermined period of time or more.
    Type: Grant
    Filed: May 23, 2002
    Date of Patent: April 13, 2004
    Assignees: Komatsu Ltd., Gigaphoton Inc.
    Inventors: Kiyoharu Nakao, Osamu Wakabayashi
  • Publication number: 20030099270
    Abstract: In a gas laser device, a compensation time according to electric charges accumulated in a charging capacitor is calculated and, when the compensation time lapsed from a time when an outer trigger was input, a compensation trigger is output to a semiconductor switch to electrically connect the charging capacitor and a first-stage capacitor, whereby a time between the input of the outer trigger and the occurrence of light emission across discharge electrodes becomes constant in each pulse and a semiconductor substrate can be exposed to light with higher accuracy even when any components of a pulse power source are affected by a temperature change.
    Type: Application
    Filed: November 21, 2002
    Publication date: May 29, 2003
    Inventor: Kiyoharu Nakao
  • Patent number: 6535539
    Abstract: An excimer laser device which neither corrodes due to a laser gas nor contaminates the laser gas is provided. For this purpose, in an excimer laser device including a cross flow fan (1) disposed in a chamber (2) for circulating a laser gas, magnetic bearings (12, 12) having outer ring magnet coils (11, 11) and inner ring magnetic substances (10, 10) for rotatably supporting a rotating shaft (9) by magnetic force, and a motor (49) having a stator (47) and a rotor (48) for directly and rotationally driving the cross flow fan (1), the outer ring magnet coils (11, 11), the inner ring magnetic substances (10, 10), the rotor (48), and the stator (47) are respectively housed in shielded spaces shielded from the laser gas.
    Type: Grant
    Filed: November 4, 1999
    Date of Patent: March 18, 2003
    Assignees: Komatsu Ltd., Ebara Corporation
    Inventors: Kiyoharu Nakao, Hisashi Nara, Shunsuke Yoshioka
  • Publication number: 20020196823
    Abstract: An injection locking type or MOPA type of laser device capable of always obtaining stable output energy and wavelength is provided. For this purpose, the laser device includes an oscillator (11A) for oscillating seed laser light (21A) with wavelength band-narrowed by a band-narrowing unit (30), an amplifier (11B) for amplifying the seed laser light and emitting the amplified laser light (21B), a wavelength monitor (34A) for detecting at least a wavelength characteristic of the seed laser light, and a laser controller (29) for performing adjustment oscillation to contain a wavelength characteristic within a predetermined allowable range, at a time of startup or when laser oscillation is suspended for a predetermined period of time or more.
    Type: Application
    Filed: May 23, 2002
    Publication date: December 26, 2002
    Inventors: Kiyoharu Nakao, Osamu Wakabayashi
  • Publication number: 20020141470
    Abstract: An injection locking type or MOPA type of laser device capable of always providing stable output energy and wavelength is provided. For this purpose, the laser device includes an oscillator for exciting laser gas by oscillator discharge and oscillating seed laser light with band-narrowed wavelength, an amplifier for amplifying the seed laser light by amplification discharge to emit amplified laser light, a delay circuit for setting at least one of a delay time from light emission of the seed laser light to light emission of the amplified laser light, and a delay time from start of the oscillator discharge to start of the aforementioned amplification discharge, and a delay time compensation circuit for performing compensation of the delay circuit so that the delay time becomes an optimal delay time.
    Type: Application
    Filed: March 12, 2002
    Publication date: October 3, 2002
    Inventors: Kiyoharu Nakao, Yoshifumi Ueno
  • Patent number: 6337872
    Abstract: The invention provides an once through fan for an excimer laser apparatus having a reduced vibration and being capable of increasing a rotational speed. In order to obtain this, in an once through fan (1) for an excimer laser apparatus provided with a blade portion (6) having a plurality of blades, a rotary shaft (4) for rotating the blade portion and a magnetic bearing (7) rotatably supporting the rotary shaft in a non-contact manner so as to circulate a laser gas sealed within a chamber (2) in accordance with a rotation of the blade portion, a rotor (21) of a motor (23) installed within the chamber (2) and rotating the rotary shaft (4) is mounted on an outer peripheral portion of the rotary shaft, and at least one magnetic bearing (7, 7) for supporting the rotary shaft is arranged in each of both sides in an axial direction of the rotor.
    Type: Grant
    Filed: October 25, 1999
    Date of Patent: January 8, 2002
    Assignees: Komatsu Ltd., Ebara Corporation
    Inventors: Hisashi Nara, Kiyoharu Nakao, Hakaru Mizoguchi, Toshihiro Nishisaka, Tatsuo Enami
  • Patent number: 4440134
    Abstract: A fuel injection system for an internal combustion engine employing a rotary valve for delivering fuel to fuel injectors in which fuel injection timing is precisely controlled to an optimum range by automatically controlling the rotary valve in response to the number of revolutions of the engine. The system includes a high pressure accumulator connected to a fuel pump and a low pressure accumulator connected to a tank through a variable restrictor valve. The rotary valve functions to selectively connect each injector to the high and low pressure accumulators as it rotates whereby metered amount of fuel can be fed into a plunger chamber of each injector when a piston chamber of the injector is connected to the low pressure accumulator and the fuel can be injected through nozzle orifices when the piston chamber is connected to the high pressure accumulator.
    Type: Grant
    Filed: May 14, 1982
    Date of Patent: April 3, 1984
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Kiyoharu Nakao, Fumihide Sato
  • Patent number: 4359984
    Abstract: A fuel control device for a diesel engine injection system having a motor-driven pump for supplying fuel to the injectors of said engine by driving a fuel pump with a DC motor, means for outputting a first motor-driven pump speed instruction signal according to a throttle position and an engine speed, a function generator for outputting a motor-driven pump armature current setting signal according to an engine speed along a torque curve preset for said engine, a motor speed detecting circuit for detecting an armature current of said motor-driven pump, to output an armature current signal, an integrator for integrating a difference between said armature current setting signal and an actual armature current signal, to output a second motor-driven pump speed instruction signal, and a minimum signal priority circuit for outputting a smaller one of said first and second instruction signals in priority, to control the armature current, whereby the speed of said motor-driven pump is regulated according to an engine
    Type: Grant
    Filed: May 20, 1980
    Date of Patent: November 23, 1982
    Inventor: Kiyoharu Nakao
  • Patent number: 4108269
    Abstract: The control system comprises an induction cable installed along a running course between a loading station and unloading station, a detecting coil mounted on a work vehicle for detecting current flowing through the induction cable, a steering control device responsive to the output of the detecting coil for steering the vehicle to run along the running course, a vehicle position detector for detecting the vehicle reaching a predetermined position, a vehicle speed commanding device responsive to the output of the vehicle position detector for commanding acceleration and deceleration of the vehicle, and a vehicle speed control device responsive to the difference between the commanded vehicle speed and the actual vehicle speed for controlling the vehicle speed. Thus, the vehicle is controlled to run along a predetermined running course between the loading station and the unloading station.
    Type: Grant
    Filed: May 12, 1977
    Date of Patent: August 22, 1978
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventor: Kiyoharu Nakao
  • Patent number: 4027554
    Abstract: In an electronic control apparatus of an automatic speed changing apparatus for use in an internal combustion engine of the type wherein the engine is connected with a load through a fluid type torque converter and a multiple stage gear changer, there are provided means for locking-up the torque converter when the speed of the output shaft thereof exceeds a first predetermined speed, means for shifting-up the gear changer to a higher stage when the speed of the output shaft exceeds a second predetermined speed which is higher than the first predetermined speed, and means for shifting-down the gear changer to a lower stage when the speed of the output shaft decreases below a third predetermined speed which is lower than the first predetermined speed whereby effecting automatic speed change control while the torque converter is maintained in the locked-up condition.
    Type: Grant
    Filed: July 24, 1974
    Date of Patent: June 7, 1977
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Terukazu Ito, Kiyoharu Nakao, Teruo Minami, Masaru Uenoyama