Patents by Inventor Yoichiro Tabata

Yoichiro Tabata 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: 7382087
    Abstract: An ozone generating system and an ozone generating method producing ozone at a high concentration and operating at high efficiency, in which a raw material gas with no nitrogen added and mainly containing oxygen is used. The amount of generation of NOX by-product is null. A raw material gas not containing nitrogen and mainly containing oxygen is supplied to an ozone generator, an AC voltage is applied to produce discharge light having a wavelength of 428 nm to 620 nm, a catalytic material containing a photocatalytic material with a band gap energy of 2.0 eV to 2.9 eV is provided on an electrode or a dielectric in a discharge region, gas pressure is kept at 0.1 MPa to 0.4 MPa, and ozone is generated.
    Type: Grant
    Filed: December 14, 2004
    Date of Patent: June 3, 2008
    Assignee: Toshiba Mitsubishi-Electric Industrial Systems Corporation
    Inventors: Yoichiro Tabata, Yujiro Okihara, Masayuki Ishikawa, Tetsuya Saitsu, Hatsuo Yotsumoto
  • Publication number: 20070134140
    Abstract: A compact, inexpensive, large-capacity ozone generator with increased ease of apparatus maintenance. An ozone power supply includes an n-phase inverter for obtaining an AC voltage having a predetermined frequency and outputting an n-phase AC voltage waveform; n reactors and an n-phase transformer for converting an n-phase AC voltage to a high AC voltage; n high-voltage terminals for outputting the n-phase high AC voltage; and a low-voltage terminal having a common potential. Ozone generator units are electrically divided into n pieces within a discharge chamber. Each ozone generator unit includes n high-voltage electrode terminals and one low-voltage electrode terminal, common to all ozone generator units. Each ozone generator unit supports an n-phase AC discharge to generate ozone.
    Type: Application
    Filed: September 29, 2004
    Publication date: June 14, 2007
    Applicant: TOSHIBA MITSUBISHI-ELECTRIC INDUSTRIAL SYSTEMS COR
    Inventors: Yoichiro Tabata, Yujiro Okihara, Masayuki Ishikawa, Tetsuya Saitsu
  • Publication number: 20060049738
    Abstract: An ozone generating system and an ozone generating method producing ozone at a high concentration and operating at high efficiency, in which a raw material gas with no nitrogen added and mainly containing oxygen is used. The amount of generation of NOX by-product is null. A raw material gas not containing nitrogen and mainly containing oxygen is supplied to an ozone generator, an AC voltage is applied to produce discharge light having wavelength of 428 nm to 620 nm, a catalytic material containing a photocatalytic material with a band gap energy of 2.0 eV to 2.9 eV is provided on an electrode or a dielectric in a discharge region, gas pressure is kept at 0.1 MPa to 0.4 MPa, and ozone is generated.
    Type: Application
    Filed: December 14, 2004
    Publication date: March 9, 2006
    Applicant: Toshiba Mitsbishi-Electric Industrial Systems Corporation
    Inventors: Yoichiro Tabata, Yujiro Okihara, Masayuki Tetsuyasaitsu, Hatsuo Yotsumoto
  • Publication number: 20030133854
    Abstract: The present invention provides a system for supplying a gas capable of supplying a gas at a proper flow rate and forming a gas at a proper rate from a gas-forming unit. The invention provides a system for supplying a gas including a gas-forming unit, a gas supply passage for supplying a gas produced from the gas-forming unit, a gas flow rate controller provided in the gas supply passage, a gas discharge passage provided in parallel with the gas supply passage to discharge the gas produced from the gas-forming unit, and a pressure controller provided in the gas discharge passage to control the pressure of the gas flowing through the gas discharge passage. In the above system for supplying a gas, it is possible to optimize the flow rate of the gas that is supplied and the amount of the gas generated by the gas-forming unit.
    Type: Application
    Filed: August 2, 2002
    Publication date: July 17, 2003
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoichiro Tabata, Akaru Usui
  • Patent number: 6395239
    Abstract: An improvement in a short-gap ozonizer having a gap of 0.5 mm or shorter between facing flat electrodes. By adjusting the height of a spacer, sandwiched between the flat electrodes, from the flat side of the electrode, the gap is adjusted to adjust the dispersion of the gap between the flat electrodes.
    Type: Grant
    Filed: July 13, 2000
    Date of Patent: May 28, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoichiro Tabata, Akira Usui
  • Patent number: 5942196
    Abstract: An ozone generating apparatus including a discharge assembly having a common earth electrode (2) and high-voltage electrodes (3) disposed in opposition to each other with disk-like dielectric members (300) being interposed therebetween for generating electric discharge by applying a high voltage across the electrodes. A gas containing oxygen is supplied to discharge spaces (5) defined between the electrodes for generating ozone under the action of electric discharge. The discharge assembly includes a plurality of discharge cells (10a, 10b, 10c) constituted by disposing at least one of the dielectric member and the high-voltage electrode in a corresponding number relative to the earth electrode in common. A plurality of discharge assemblies are stacked and secured together to constitute a block A plurality of blocks are stacked and secured together to constitute a module. An ozone generating apparatus of a large capacity easy to effectuate assembling and maintenance is realized in a compact structure.
    Type: Grant
    Filed: July 9, 1997
    Date of Patent: August 24, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoichiro Tabata, Masaki Kuzumoto
  • Patent number: 5726419
    Abstract: In pulse welding apparatus of arc welding or short-circuit transfer type arc welding in which a pulse discharge created on the tip of a wire electrode is utilized to perform welding, when a molten droplet produced on the tip of wire electrode is late to separate from the wire due to variations of welding conditions and external disturbances, the wire-supplying speed at which the wire is supplied to the weld zone changes causing undercut. To prevent this, pulse current supplied to the base metal is divided into a plurality of pulse groups and the average current reaches the maximum peak value at a predetermined time after beginning of outputting the pulses, and the group of pulse currents is of a hill-shape in its envelope in accordance with the separation phenomenon of molten droplet, and the group of pulse currents is arranged to have different pulse period, pulse width, and pulse interval.
    Type: Grant
    Filed: December 12, 1995
    Date of Patent: March 10, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoichiro Tabata, Shigeo Ueguri, Yoshihiro Ueda, Masanori Mizuno, Yoshiaki Kato, Osamu Nagano
  • Patent number: 5495091
    Abstract: In pulse welding apparatus of arc welding or short-circuit transfer type arc welding in which a pulse discharge created on the tip of a wire electrode is utilized to perform welding, when a molten droplet produced on the tip of wire electrode is late to separate from the wire due to variations of welding conditions and external disturbances. The wire-supplying speed at which the wire is supplied to the weld zone changes. This causes undercut, i.e., a defect in welding bead-shape that presents adverse effect to welding quality. To prevent this problem, pulse current supplied to the base metal is divided into a plurality of pulse groups and the average current reaches the maximum peak value at a predetermined time after beginning of outputting the pulses, and the group of pulse currents is of a hill-shape in its envelope in accordance with the separation phenomenon of molten droplet, and the group of pulse currents is arranged to have different pulse period, pulse width, and pulse interval.
    Type: Grant
    Filed: July 22, 1994
    Date of Patent: February 27, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoichiro Tabata, Shigeo Ueguri, Yoshihiro Ueda, Masanori Mizuno, Yoshiaki Kato, Osamu Nagano
  • Patent number: 5452317
    Abstract: A metal vapor laser apparatus is provided with a buffer gas and a laser medium are enclosed in a tube and the gas is utilized as an excitation or ionization medium in the tube. The metal vapor laser apparatus comprises molecules consisting of a plurality of elements and mixed by at least 0.1% in the gas enclosed in the tube and a gas having a molecular weight lighter than that of neon mixed by at least 0.1% in the gas enclosed in the tube.
    Type: Grant
    Filed: September 22, 1994
    Date of Patent: September 19, 1995
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoichiro Tabata, Kazuhiko Hara, Akihiko Iwata, Shigeo Ueguri, Hiroshi Masuda, Yoshibumi Minowa
  • Patent number: 5416299
    Abstract: A pulse welding apparatus using a pulse discharge such as a pulse arc welding apparatus and a short-circuit transfer arc welding apparatus. A pulse current waveform control circuit, which controls the pulse arc current so that a desired pulse arc current is supplied to the arc welding power supply for outputting the pulse arc current to the welding load unit, is constructed such that the optimum welding operation may be performed without having to adjust circuit components and modify circuit design. The pulse current waveform control circuit is in the form of a microcomputerized digital circuit which operates under a program to provide a desired pulse arc current. A modification of the program can provide any desired pulse arc currents without changing circuits. The optimum welding current waveform parameters or a target arc length signal is learned in the first welding stage and stored into a memory.
    Type: Grant
    Filed: February 9, 1994
    Date of Patent: May 16, 1995
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoichiro Tabata, Shigeo Ueguri, Yoshihiro Ueda, Masanori Mizuno, Yoshiaki Katou, Osamu Nagano
  • Patent number: 5406052
    Abstract: The welding equipment according to the present invention divides the pulsed electric current fed to a base metal in the course of a welding process into a plural number of pulse groups, performing instantaneous control over the base electric current period and the base electric current value applied to each of the pulse intervals of the individual pulses within such a group of pulsed electric currents and to each of the groups of pulsed electric currents, the pulse peak value and pulse width of each pulse, and such instantaneous control over a short circuit period and an arc period in the course of performance of the short circuiting transfer arc welding process, in accordance with the detected arc length, in such a manner that an ideal target arc length is thereby achieved.
    Type: Grant
    Filed: October 26, 1990
    Date of Patent: April 11, 1995
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Masanori Mizuno, Yoshiaki Katou, Osamu Nagano, Yoichiro Tabata, Shigeo Ueguri, Yoshihiro Ueda
  • Patent number: 5317116
    Abstract: A pulse welding apparatus using a pulse discharge such as a pulse arc welding apparatus and a short-circuit transfer arc welding apparatus. A pulse current waveform control circuit, which controls the pulse arc current so that a desired pulse arc current is supplied to the arc welding power supply for outputting the pulse arc current to the welding load unit, is constructed such that the optimum welding operation may be performed without having to adjust circuit components and modify circuit design. The pulse current waveform control circuit is in the form of a microcomputerized digital circuit which operates under a program to provide a desired pulse arc current. A modification of the program can provide any desired pulse arc currents without changing circuits. The optimum welding current waveform parameters or a target arc length signal is learned in the first welding stage and stored into a memory.
    Type: Grant
    Filed: March 27, 1991
    Date of Patent: May 31, 1994
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoichiro Tabata, Shigeo Ueguri, Yoshihiro Ueda, Masanori Mizuno, Yoshiaki Katou, Osamu Nagano
  • Patent number: 5281791
    Abstract: A pulsed arc welding for carrying out arc welding or short-circuit transfer type arc welding by utilizing the pulsed discharge generated at the tip of a wire electrode. The propensity of wire electrode curvature causes irregular changes in the contact point of the wire electrode and variations in the arc length between the wire electrode tip and workpieces. Consequently, the invention detects arc voltage and current and checks the instantaneous variation in the arc length. The arc voltage value thus detected is converted to a reference arc voltage variable. Then the detected arc voltage value is compared with the reference value to compute a true arc length. A simulation arc length signal, which varies as welding proceeds, and a reference simulation welding current waveform are set, to compare the simulation arc length signal with the computed arc length signal.
    Type: Grant
    Filed: December 27, 1990
    Date of Patent: January 25, 1994
    Assignee: Mitsubishi Denki K.K.
    Inventors: Yoichiro Tabata, Shigeo Ueguri, Yoshihiro Ueda, Masanori Mizuno, Yoshiaki Katou, Osamu Nagano
  • Patent number: 5243230
    Abstract: A pulse generator circuit which comprises a power supply source for outputting a high voltage signal. A first capacitor is charged with the high voltage signal output by the power supply source. A load device is supplied with the high voltage signal charged in the first capacitor. A semiconductor switch together with the first capacitor and the load constitute a closed loop. A first diode is inserted between the power supply source and the closed loop. A second diode is inserted in a closed loop and operates to suppress electrical vibrations. A second diode may have an opposite polarity to that of the first diode. A snubber circuit may also be inserted in parallel across the second diode.
    Type: Grant
    Filed: March 30, 1992
    Date of Patent: September 7, 1993
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hiroshi Itou, Akihiko Iwata, Tatsuki Okamoto, Yoshihiro Ueda, Yoichiro Tabata
  • Patent number: 5150375
    Abstract: A substance vaporizing apparatus which uses a vapor of a substance generated by heating the substance in a gas-filled tube as an exciting medium or an ionizing medium. The apparatus employs an improved container for containing the substance within the gas-filled tube. The improved container suppresses the rate of emission of the vapor of the substance into a discharge space defined by the gas-filled tube to hold the vapor density of the substance at an optimum low value for laser oscillation relative to the buffer gas density in the discharge space. Thus, the mean free path of the atoms of the substance, namely the average distance traveled by the atoms between elastic collisions with the electrons, ions and neutral atoms of the buffer gas, is increased to increase the number of atoms of the subtance excited to a higher energy level, which, consequently, increases laser power and enhances laser beam or ion beam accelerating energy.
    Type: Grant
    Filed: June 11, 1990
    Date of Patent: September 22, 1992
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoichiro Tabata, Yoshihiro Ueda, Shigeo Ueguri, Kazuhiko Hara
  • Patent number: 5122674
    Abstract: In a pulse generator circuit for a laser unit etc., plural semiconductor switches arranged in matrix alignment on an outer surface of a first tube are connected in series and parallel with one another, and an end of each series-connection of the semiconductor switches is electrically connected to a second tube provided in coaxial alignment to the first tube, thereby realizing a synthetic semiconductor switch for switching high voltage and large current between the other end of the series-connection of the semiconductor switches and the second tube.
    Type: Grant
    Filed: December 4, 1990
    Date of Patent: June 16, 1992
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hiroshi Itou, Akihiko Iwata, Tatsuki Okamoto, Yoshihiro Ueda, Shinji Murata, Takashi Kumagai, Yoichiro Tabata
  • Patent number: 5043557
    Abstract: A load voltage detecting device for use in an apparatus for supplying a current variable with time to a load section. The load voltage detecting device for an apparatus such as a pulsed are welding machine can accurately detect the load voltage from the output voltage of the pulse current supplying section without being affected by the reactor component and the resistance component of the load section and the elements extended to the load section such as the cables and the welding torch.
    Type: Grant
    Filed: June 29, 1989
    Date of Patent: August 27, 1991
    Assignee: Mitsubishi Denki K.K.
    Inventors: Yoichiro Tabata, Shigeo Ueguri, Yoshihiro Ueda
  • Patent number: 4994646
    Abstract: A pulse arc discharge welding apparatus comprising a pulse current waveform control circuit for periodically outputting a pulse current group consisting of a plurality of pulses, pulse arc current supplying means for outputting a pulse arc current according to an output of said pulse current waveform control circuit and an arc welding means for performing pulse arc discharge with an output of said pulse arc current supplying means, to carry out a pulse arc welding operation. In such a pulse arc discharge welding apparatus, with a discharge current waveform provided in the form of high frequency pulses, the discharge light and the gas in pulse discharge and the electrode are regulated and controlled with high accuracy.
    Type: Grant
    Filed: May 18, 1989
    Date of Patent: February 19, 1991
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoichiro Tabata, Shigeo Ueguri, Yoshihiro Ueda
  • Patent number: 4418265
    Abstract: An electrical welding device which requires no high frequency insulation and an electrical discharge gap for maintaining the arc discharge is made large. A main power source supplies an arc discharge current through an electrical conductor to the welding electrode. A high frequency electric power source applies a high-frequency high voltage between the electrode and the material to be welded to generate a high frequency discharge for arc ignition in the electric discharge gap. A high frequency magnetic choke element, which is preferably a plurality of stacked annular ferrite discs, surrounds a predetermined part of the electrical conductor. A high-frequency bypass capacitor is utilized to ground the electrical conductor between the magnetic choke element and the main power source.
    Type: Grant
    Filed: March 3, 1981
    Date of Patent: November 29, 1983
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoichiro Tabata, Shigeo Ueguri, Hirotsugu Komura, Toshio Ito