Patents by Inventor Youichi Kojima

Youichi Kojima 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: 6362950
    Abstract: This invention relates to solid electrolyte capacitors and is intended to decrease the contact resistance between the body of the capacitor and lead frames and the internal resistance of these components. The, invention provides a process for producing a solid electrolyte capacitor by forming a dielectric oxide film on an anode body of valve metal, forming a cathode layer of solid conductive substance on the oxide film to prepare a capacitor element, coating the cathode layer of the capacitor element with a carbon layer, coating the carbon layer with a silver paste layer to prepare a capacitor body, and bonding a lead frame to the silver paste layer of the. capacitor body with a silver adhesive. While the capacitor element coated with the carbon layer and a silver paste are being vibrated relative to each other, the capacitor element is dipped in the silver paste and withdrawn therefrom in the direction of the vibration, whereby the carbon layer is coated with the silver paste layer.
    Type: Grant
    Filed: February 7, 2000
    Date of Patent: March 26, 2002
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Hidenori Kamigawa, Yasuhiro Kishimoto, Youichi Kojima, Takeshi Takamatsu, Hiroshi Yakui
  • Patent number: 6313979
    Abstract: The invention provides a process for producing solid electrolyte capacitors by forming a dielectric oxide film and a first cathode layer of solid conductive substance over the surface of an anode body of valve metal, and forming a second cathode layer of conductive high polymer on the first cathode layer by electrolytic oxidative polymerization. The second cathode layer is formed by immersing in the electrolyte the anode body formed over the surface thereof with the oxide film and the first cathode layer, feeding a positive voltage with an external electrode piece in contact with the first cathode layer in the electrolyte, and shifting the feeding point at a predetermined time interval.
    Type: Grant
    Filed: November 8, 2000
    Date of Patent: November 6, 2001
    Assignees: Sanyo Electric Co., Ltd., Sanyo Electronic Components Co., Ltd.
    Inventors: Yutaka Taketani, Kakusyo Yoshida, Hidenori Kamigawa, Yasuhiro Kishimoto, Youichi Kojima, Takeshi Takamatsu
  • Patent number: 6168639
    Abstract: The invention provides a process for producing solid electrolyte capacitors by forming a dielectric oxide film and a first cathode layer of solid conductive substance over the surface of an anode body of valve metal, and forming a second cathode layer of conductive high polymer on the first cathode layer by electrolytic oxidative polymerization. In forming the second cathode layer, the pH of the electrolyte to be used for electrolytic oxidative polymerization is maintained within a predetermined range by adding an acid or alkali to the electrolyte. Since the pH of the electrolyte remains substantially unaltered by the polymerization according to the invention, the electrolyte is repeatedly usable while permitting the resulting second cathode layers to retain the desired electric conductivity.
    Type: Grant
    Filed: October 6, 1998
    Date of Patent: January 2, 2001
    Assignees: Sanyo Electric Co., Ltd., Sanyo Electronic Components Co., Ltd.
    Inventors: Yutaka Taketani, Kakusyo Yoshida, Hidenori Kamigawa, Yasuhiro Kishimoto, Youichi Kojima, Takeshi Takamatsu
  • Patent number: 6139592
    Abstract: The object of the invention is to provide a process for producing an organic solid electrolyte capacitor which is diminished in leakage current, and an apparatus for use in practicing the process. The process includes the steps of completing a capacitor element by forming a dielectric oxide film over an anode body of valve metal and subsequently forming a cathode layer of solid conductive organic material over the oxide film, subjecting the capacitor element to an aging treatment, and forming a shell around the capacitor element.
    Type: Grant
    Filed: June 18, 1998
    Date of Patent: October 31, 2000
    Assignees: Sanyo Electric Co., Ltd., Sanyo Electronic Components Co., Ltd.
    Inventors: Hidenori Kamigawa, Youichi Kojima, Takeshi Takamatsu, Yasutoshi Sugita, Yasuhiko Ito, Tomohiro Nishio
  • Patent number: 6036734
    Abstract: This invention relates to solid electrolyte capacitors and is intended to decrease the contact resistance between the body of the capacitor and lead frames and the internal resistance of these components The invention provides a process for producing a solid electrolyte capacitor by forming a dielectric oxide film on an anode body of valve metal, forming a cathode layer of solid conductive substance on the oxide film to prepare a capacitor element, coating the cathode layer of the capacitor element with a carbon layer, coating the carbon layer with a silver paste layer to prepare a capacitor body, and bonding a lead frame to the silver paste layer of the capacitor body with a silver adhesive. While the capacitor element coated with the carbon layer and a silver paste are being vibrated relative to each other, the capacitor element is dipped in the silver paste and withdrawn therefrom in the direction of the vibration, whereby the carbon layer is coated with the silver paste layer.
    Type: Grant
    Filed: October 8, 1998
    Date of Patent: March 14, 2000
    Assignees: Sanyo Electric Co., Ltd., Sanyo Electronic Components Co., Ltd.
    Inventors: Yutaka Taketani, Kakusyo Yoshida, Hidenori Kamigawa, Yasuhiro Kishimoto, Youichi Kojima, Takeshi Takamatsu, Hiroshi Yakui
  • Patent number: 4954235
    Abstract: Disclosed herein suspension electroplating of fine particles with metal. An electroplating operatively equipped with a cathode and anode is charged with a a metallic ion-containing electrolyte and particles to be electroplated. The particles have a size of from 0.1 to 10 .mu.m. At least a part of the surface of each particle is conductive. Such a stationary circulating flow of a suspension of the particles in the electrolyte is formed in the bath that the particles are maintained in the suspended condition; the suspension is circulated substantially without coming in contact with the anode; the particles may have a chance of colliding with substantially all surface areas of the working surface of the cathode, and are repeatedly brought in collision with the cathode at a velocity with a normal component of from 0.6 to 6.0 m/min; and a particle concentration of the suspension at the time of collision is from 30 to 55% by volume.
    Type: Grant
    Filed: December 27, 1989
    Date of Patent: September 4, 1990
    Assignee: Nisshin Steel Co., Ltd.
    Inventors: Eiki Takeshima, Kiyoshi Takatsu, Youichi Kojima, Takahiro Fujii
  • Patent number: 4908106
    Abstract: Disclosed herein suspension electroplating of fine particles with metal. An electroplating operatively equipped with a cathode and anode is charged with a metallic ion-containing electrolyte and particles to be electroplated. The particles have a size of from 0.1 to 10 .mu.m. At least a part of the surface of each particle is conductive. Such a stationary circulating flow of a suspension of the particles in the electrolyte is formed in the bath that the particles are maintained in the suspended condition; the suspension is circulated substantially without coming in contact with the anode; the particles may have a chance of colliding with substantially all surface areas of the working surface of the cathode, and are repeatedly brought in collision with the cathode at a velocity with a normal component of from 0.6 to 6.0 m/min.; and a particle concentration of the suspension at the time of collision is from 30 to 55% by volume.
    Type: Grant
    Filed: April 20, 1989
    Date of Patent: March 13, 1990
    Assignee: Nisshin Steel Co., Ltd.
    Inventors: Eiki Takeshima, Kiyoshi Takatsu, Youichi Kojima, Takahiro Fujii