Patents by Inventor Shoji Yasunaga

Shoji Yasunaga 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: 20090184412
    Abstract: There is provided a resin-seal type semiconductor device (BGA type semiconductor device) whose heat dissipating characteristic is improved, so that it is prevented from deteriorating in reliability. This BGA type semiconductor device includes a wiring substrate on a predetermined area on which a semiconductor chip is mounted; a plurality of metal bumps that are formed to be arranged at predetermined intervals in an area of the substrate different from the area on which the semiconductor chip is mounted; and a sealing resin layer that covers at least the semiconductor chip. Each of the plurality of metal bumps is covered with the sealing resin layer described above, with a part thereof exposed at a top face of the sealing resin layer.
    Type: Application
    Filed: October 23, 2008
    Publication date: July 23, 2009
    Applicant: Rohm Co., Ltd.
    Inventor: Shoji Yasunaga
  • Publication number: 20080169538
    Abstract: A semiconductor device of the present invention includes a semiconductor chip, a die pad to which the semiconductor chip is bonded with solder to be mounted thereon, a plurality of leads electrically conducted to the semiconductor chip, a stress reducing layer that is provided on a rear face of the die pad opposite to a face of the die pad on which the semiconductor chip is mounted and that reduces stress applied to the semiconductor chip, and a sealing body for sealing at least the semiconductor chip.
    Type: Application
    Filed: January 11, 2008
    Publication date: July 17, 2008
    Applicant: Rohm Co., Ltd.
    Inventors: Yasumasa Kasuya, Motoharu Haga, Shoji Yasunaga
  • Patent number: 5998339
    Abstract: A wet type sliding apparatus comprising a wet type radial bearing which starts in the presence of a lubricating liquid, wherein the radial bearing has a sliding surface consisting of a resin composition comprising 10 to 45% by weight of a carbon fiber and 0.1 to 8.5% by weight of a fluorocarbon polymer, the balance being substantially an aromatic polyetherketone resin or a polyarylene sulfide resin. The radial bearing in the above wet type sliding apparatus is excellent in wear resistance even under a high load.
    Type: Grant
    Filed: October 7, 1997
    Date of Patent: December 7, 1999
    Assignee: Daido Metal Company Ltd.
    Inventors: Eiji Kato, Shoji Yasunaga, Hidehiko Tamura, Tadashi Tanaka
  • Patent number: 5879791
    Abstract: A wet type sliding apparatus comprising a thrust bearing which operates in the presence of a lubricating liquid, wherein the thrust bearing has a sliding surface composed of a resin composition comprising a carbon fiber, a fluorocarbon polymer and a thermoplastic resin other than fluorocarbon polymer, the carbon fiber content being 10 to 45% by weight based on the weight of the composition and the fluorocarbon polymer content being 0.1 to 8.5% by weight based on the weight of the composition, the thrust bearing in said wet type sliding apparatus being excellent in wear resistance, mechanical strength and friction coefficient at the time of starting even under a high load.
    Type: Grant
    Filed: September 25, 1996
    Date of Patent: March 9, 1999
    Assignee: Daido Metal Company Ltd.
    Inventors: Eiji Kato, Shoji Yasunaga, Hidehiko Tamura, Tadashi Tanaka
  • Patent number: 5821204
    Abstract: A thrust bearing having a sliding surface composed of a resin composition which comprises 10 to 45% by weight of a carbon fiber, 0.1 to 30% by weight of a polytetrafluoroethylene, 0.1 to 20% by weight of a graphite having an oil absorption of 70 to 500 ml/100 g, the balance being substantially an aromatic polyetherketone resin wherein the total content of the carbon fiber, the polytetrafluoroethylene and the graphite is not more than 65% by weight. The sliding surface of the above thrust bearing is excellent in wear resistance and low in friction coefficient at the time of starting.
    Type: Grant
    Filed: April 21, 1997
    Date of Patent: October 13, 1998
    Assignee: Daido Metal Company Ltd.
    Inventors: Eiji Kato, Shoji Yasunaga, Takayuki Shibayama