Patents by Inventor Sadahiko Yokoyama

Sadahiko Yokoyama 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: 6522149
    Abstract: Waste plastics, which contain coloring agents and are in various forms, are heated and electrified to divide into three groups in order to collect them without crushing while maintaining their product forms. Each group consists of high exothermic plastics, low exothermic plastics or PVC.
    Type: Grant
    Filed: April 30, 2001
    Date of Patent: February 18, 2003
    Assignee: NEC Corporation
    Inventors: Sadahiko Yokoyama, Takaaki Matsushima
  • Publication number: 20020027943
    Abstract: A plastic identifying apparatus, includes a heating unit, a measuring unit, and a displaying unit. The heating unit heats a plastic object. The measuring unit measures a temperature of the plastic object to generate a measurement result and outputs a result data indicating the measurement result. The displaying unit displays the result data on the plastic object.
    Type: Application
    Filed: August 23, 2001
    Publication date: March 7, 2002
    Applicant: NEC CORPORATION
    Inventors: Sadahiko Yokoyama, Takaaki Matsushima
  • Publication number: 20010054900
    Abstract: Waste plastics, which contain coloring agents and are in various forms, are heated and electrified to divide into three groups in order to collect them without crashing while maintaining their product forms. Each group consists of high exothermic plastics, low exothermic plastics or PVC.
    Type: Application
    Filed: April 30, 2001
    Publication date: December 27, 2001
    Inventors: Sadahiko Yokoyama, Takaaki Matsushima
  • Patent number: 6290919
    Abstract: In an electrostatic separating apparatus which separates supplied substances containing sheet-like substances into conductive substances and insulating substances by using electrostatic force and corona discharge together, a ground electrode unit has a carrier belt tensioned for a plurality of rotation rollers. An opposite electrode unit is provided with a first electrostatic electrode, a corona electrode, and a second electrostatic electrode in this order from a supply side of the supplied substances. A removing unit separates and removes the insulating substances attached to the ground electrode unit.
    Type: Grant
    Filed: March 24, 2000
    Date of Patent: September 18, 2001
    Assignee: NEC Corporation
    Inventors: Sadahiko Yokoyama, Masao Shimoda, Masatoshi Iji, Tokukazu Kiji
  • Patent number: 6244445
    Abstract: A hollow rotating drum 1 is provided in an oblique manner and is rotated by two pairs of rollers 3a, 3b. A size classification unit 2 is provided in the vicinity of a center of the rotating drum in a lengthwise direction of the drum, and water is added from a water addition unit 4. An object to be moisturized is supplied from an opening on an upper portion of the rotating drum in a supplying direction 5 of the object. Then, the object is moved spirally within the rotating drum to be moisturized. An object, i.e., a moisture-processed substance having a size equal to or smaller than the predetermined size is classified by the size classification unit to be continuously discharged in a direction 6 of movements of the moisture-processed substance. Also, an object, i.e., residue having a larger size than the predetermined size, is continuously discharged from an opening on an underside of the rotating drum in a direction 7 of movements of the residue.
    Type: Grant
    Filed: May 25, 2000
    Date of Patent: June 12, 2001
    Assignee: NEC Corporation
    Inventors: Sadahiko Yokoyama, Masao Shimoda, Tokukazu Kiji
  • Patent number: 5801358
    Abstract: A joining member for joining parts or materials to form a joined structure is constituted by a composite material containing a heating assistant in a matrix material. For disintegrating the joined structure, it is placed in a heating zone, and a high frequency magnetic field or a high frequency electric field, or a high frequency magnetic field and a high frequency electric field are applied to the joining member. The heating assistant may be in a form of a particle or a fiber containing at least one of a soft magnetic material, an electrically conducting material and a dielectric material. The matrix material may be plastic or ceramic. The disintegration of the joined structure can be efficiently and selectively carried out, thus contributing to efficient recycling.
    Type: Grant
    Filed: June 26, 1997
    Date of Patent: September 1, 1998
    Assignee: NEC Corporation
    Inventors: Sadahiko Yokoyama, Masatoshi Iji
  • Patent number: 5780536
    Abstract: A joining member for joining parts or materials to form a joined structure is constituted by a composite material containing a heating assistant in a matrix material. For disintegrating the joined structure, it is placed in a heating zone, and a high frequency magnetic field or a high frequency electric field, or a high frequency magnetic field and a high frequency electric field are applied to the joining member. The heating assistant may be in a form of a particle or a fiber containing at least one of a soft magnetic material, an electrically conducting material and a dielectric material. The matrix material may be plastic or ceramic. The disintegration of the joined structure can be efficiently and selectively carried out, thus contributing to efficient recycling.
    Type: Grant
    Filed: July 24, 1996
    Date of Patent: July 14, 1998
    Assignee: NEC Corporation
    Inventors: Sadahiko Yokoyama, Masatoshi Iji
  • Patent number: 5743936
    Abstract: The method of recovering valuables from a printed wiring board on which electronic components are mounted, includes the steps of (a) removing electronic components from a printed wiring board on which the electronic components are mounted, (b) polishing a surface of the printed wiring board from which the electronic components have been removed in the step (a), (c) milling the printed wiring board a surface of which has been polished in the step (b), and (d) separating milled portions of the printed wiring board into portions mainly including copper and portions mainly including resin and filler. The electronic components recovered in accordance with the method includes valuables such as gold having greater grade than natural minerals. The copper recovered in accordance with the method includes no impurities such as solder, and thus can be reclaimed as metal resource having high added value.
    Type: Grant
    Filed: May 17, 1996
    Date of Patent: April 28, 1998
    Assignee: NEC Corporation
    Inventors: Sadahiko Yokoyama, Masatoshi Iji
  • Patent number: 5715592
    Abstract: A printed wiring board, on which an electronic parts are mounted and fixed by way soldering, is introduced into a heating furnace for heating at a temperature higher than or equal to a melting temperature of a solder. After sufficiently melting of solder, an impact force and/or a shearing force are applied. By this under a reduced connecting force, the electronic parts are removed from a printed wiring board. On the other hand, since the parts can be easily removed from the printed wiring board. Also, the parts and the printed circuit are separated for collecting useful substance and can improve resistance to enhance recycling efficiency.
    Type: Grant
    Filed: November 6, 1995
    Date of Patent: February 10, 1998
    Assignee: NEC Corporation
    Inventors: Eiichi Mori, Sadahiko Yokoyama, Masatoshi Iji, Yuji Ikuta
  • Patent number: 5676318
    Abstract: In a method of grinding a printed circuit board, a printed circuit board having various parts mounted thereon, or a residual ground product produced in the manufacturing process for the boards, and recovering valuable substances by separating the ground product into a portion containing a large amount of metal component such as copper and a portion consisting a resin, a filler material, and the like through a separation step, the separation step includes a specific gravity separation step of separating the ground product into a portion containing a large amount of substance having a high specific gravity and a portion containing a large amount of substance having a low specific gravity, and an electrostatic separation step of separating the ground product into a portion having a large amount of conductor and a portion containing large amount of insulator. The grinding step includes a coarse grinding step and a fine grinding step.
    Type: Grant
    Filed: March 8, 1995
    Date of Patent: October 14, 1997
    Assignee: NEC Corporation
    Inventors: Sadahiko Yokoyama, Masatoshi Iji