Patents by Inventor Osamu Furukawa

Osamu Furukawa 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: 4882652
    Abstract: When a portion of the Pb of a Pb(Zn.sub.1/3 Nb.sub.2/3)O.sub.3 -based ceramic composition within the region bounded by lines connecting a, b, c, d, e and f points in the ternary composition diagram of the accompanying FIG. 1 is substituted by a small amount of Ca, a high dielectric constant type ceramic composition is obtained which has a small temperature coefficient of dielectric constant and which is effective as a material for multilayer ceramic capacitors.
    Type: Grant
    Filed: November 2, 1987
    Date of Patent: November 21, 1989
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Osamu Furukawa, Mitsuo Harata, Takaaki Yasumoto, Motomasa Imai
  • Patent number: 4818736
    Abstract: When a portion of the Pb of a Pb(Zn.sub.1/3 Nb.sub.2/3)O.sub.3 -based ceramic composition within the region bounded by lines connecting a, b, c and d points in the ternary composition diagram of the accompanying FIG. 1 is substituted by a small amount of Ba and/or Sr, a high dielectric constant type ceramic composition which has a small temperature coefficient of dielectric constant and which is effective as a material for multilayer ceramic capacitors is obtained.
    Type: Grant
    Filed: February 11, 1988
    Date of Patent: April 4, 1989
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yohachi Yamashita, Osamu Furukawa, Mitsuo Harata, Takashi Takahashi
  • Patent number: 4772985
    Abstract: Disclosed is a thick film capacitor comprising (a) a sintered layer of a ferroelectric material mainly consisting of one or more ferroelectric inorganic compounds having a perovskite structure and an inorganic binder having a eutectic composition which experiences a liquid phase at a temperature lower than the sintering temperature of the ferroelectric inorganic compounds, and (b) at least two electrodes formed on both surfaces of the sintered layer of the ferroelectric material. In the thick film capacitor of this invention, the perovskite structure of the ferroelectric inorganic compounds is not destroyed upon sintering. Therefore, a high degree of sintering, a good dielectric characteristic and high moisture and migration resistances can be obtained.
    Type: Grant
    Filed: September 18, 1987
    Date of Patent: September 20, 1988
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takaaki Yasumoto, Osamu Furukawa, Nobuo Iwase, Mitsuo Harata, Masao Segawa
  • Patent number: 4767732
    Abstract: To obtain a ceramic material having a high dielectric constant (K=2300 to 7000), a high insulation resistance (CR=4000 to 18000 ohmF), a low temperature dependence (.+-.10%) to (.+-.22, -33%) upon dielectric constant over a wide temperature range (-55 and +125.degree. C.) and a relatively low sintering temperature (1000.degree. C. to 1250.degree. C.), BaTiO.sub.3 powder at least 50 wt % of which is 0.7 to 3 .mu.m in particle size) is mixed with another compound with perovskite structure mainly composed of oxides of Pb, Ba, Sr, Zn, Nb, Mg and Ti before sintering. Further, part of Ti of BaTiO.sub.3 is substitutable with Zr or Sn, and part of Ba of BaTiO.sub.3 is substitutable with Sr, Ca or Ce.
    Type: Grant
    Filed: August 28, 1987
    Date of Patent: August 30, 1988
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Osamu Furukawa, Seiichi Yoshida, Motomasa Imai, Mitsuo Harata
  • Patent number: 4614253
    Abstract: A mast structure of a forklift truck is composed of two vertically and parallelly extending channel members each of which has front and rear flanges. The thickness of the rear flange is so larger than that of the front flange that a ratio (e.sub.1 /e.sub.2) of a front-side figure center distance (e.sub.1) between a front-most end of the channel member and a center of figure in cross-section to a rear-side figure center distance (e.sub.2) between a rear-most face of the channel member and the center of figure is within a range of 1.1.ltoreq.e.sub.1 /e.sub.2 .ltoreq.1.5, thereby effectively improving flexural and torsional rigidities of the mast channel member of the forklift truck.
    Type: Grant
    Filed: May 21, 1984
    Date of Patent: September 30, 1986
    Assignee: Nissan Motor Co., Ltd.
    Inventor: Osamu Furukawa
  • Patent number: 4540971
    Abstract: A metal oxide varistor is disclosed which a component of grain bodies comprised of zinc oxide and a component of grain boundary layers comprised of another metallic oxide, containing metal other than zinc wherein at least a portion of these starting materials comprised a fine particle powder prepared by a co-precipitatin method.The metal oxide varistor of the present invention is excellent in varistor characteristics such as non-linearity to voltage, life performances and capability of energy dissipation, is small in a scatter of the above characteristics between manufacture lots or within each lot at the time of manufacture, and has a good quality stability. Unexpected results are obtained when the co-precipitated fine particles are subjected to a refrigeration-dehydration type process.
    Type: Grant
    Filed: June 22, 1983
    Date of Patent: September 10, 1985
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Hideyuki Kanai, Takashi Takahashi, Motomasa Imai, Osamu Furukawa, Hiroshi Endo, Osamu Hirao, Masaru Hayashi
  • Patent number: 4535314
    Abstract: A varistor having good voltage-current nonlinear characteristics and a long life performance. The varistor is formed of a sintered body consisting essentially of zinc oxide as a major component, 0.1 to 5 mol % of bismuth in terms of Bi.sub.2 O.sub.3, 0.1 to 5 mol % of cobalt in terms of Co.sub.2 O.sub.3, 0.1 to 5 mol % of manganese in terms of MnO, 0.1 to 5 mol % of antimony in terms of Sb.sub.2 O.sub.3, 0.1 to 5 mol % of nickel in terms of NiO, and 0.001 to 0.05 mol % of aluminum in terms of Al.sup.3+.
    Type: Grant
    Filed: December 19, 1983
    Date of Patent: August 13, 1985
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Hideyuki Kanai, Takashi Takahashi, Motomasa Imai, Osamu Furukawa
  • Patent number: 4527146
    Abstract: A varistor comprising a basic component consisting essentially of ZnO as a principal constituent and, as auxiliary components, bismuth (Bi), cobalt (Co), manganese (Mn), antimony (Sb) and nickel (Ni) in an amount, when calculated in terms of Bi.sub.2 O.sub.3, Co.sub.2 O.sub.3, MnO, Sb.sub.2 O.sub.3 and NiO, respectively, of Bi.sub.2 O.sub.3 : 0.1 to 5 mol %, Co.sub.2 O.sub.3 : 0.1 to 5 mol %, MnO: 0.1 to 5 mol %, Sb.sup.2 O.sub.3 : 0.1 to 5 mol % and NiO: 0.1 to 5 mol %; and an additional constituent comprising boron (B) in an amount, when calculated in terms of B.sub.2 O.sub.3, of 0.001 to 1 wt % based on said basic component, the Bi.sub.2 O.sub.3 of the sintered body comprising not less than 30% of .alpha.-phase . In another embodiment, the above basic component may further comprise at least one of Al, In and Ga in a prescribed amount and the above additional component may be (i) B with or without at least one of Ag and Si in a prescribed amount or (ii) a glass containing B in a prescribed amount.
    Type: Grant
    Filed: December 22, 1983
    Date of Patent: July 2, 1985
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Hideyuki Kanai, Osamu Furukawa, Motomasa Imai, Takashi Takahashi
  • Patent number: 4516105
    Abstract: Disclosed is a metal oxide varistor which comprises; a sintered body containing (a) ZnO as a principal component, and (b), as auxiliary components, Bi, Co and Mn in amounts of 0.05.about.2 mole %, 0.05.about.2 mole % and 0.05.about.2 mole %, when calculated in terms of Bi.sub.2 O.sub.3, Co.sub.2 O.sub.3 and MnO.sub.2, respectively, and at least one selected from Al, In and Ga in amounts of 1.times.10.sup.-4 .about.3.times.10.sup.-2 mole %, when calculated in terms of Al.sub.2 O.sub.3, In.sub.2 O.sub.3 and Ga.sub.2 O.sub.3, respectively; said sintered material having been reheated at a temperature of 650.degree..about.900.degree. C. after sintering; and a non-diffusible electrode provided on said sintered body. The metal oxide varistor has excellent pulse response and volt-ampere non-linearity even with respect to a pulse having a short rise time of less than a microsecond.
    Type: Grant
    Filed: July 6, 1982
    Date of Patent: May 7, 1985
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Motomasa Imai, Takashi Takahashi, Osamu Furukawa, Hideyuki Kanai
  • Patent number: 4395810
    Abstract: A method for covering sodium conveying piping in a fast breeder reactor which makes use of metallic sodium as a coolant material is described herein, which method consists of the steps of preparing a covering material by mixing a raw material having sodium resistance and silicate or phosphate under a wet condition and after press-shaping said mixture drying the shaped mixture, and covering the sodium conveying piping with said covering material, whereby dispersion of leaked metallic sodium from the piping can be prevented.
    Type: Grant
    Filed: August 8, 1979
    Date of Patent: August 2, 1983
    Assignees: Dohryokuro Kakunenryo Kaihatsujigyodan, Asahi Asbestos Co., Ltd.
    Inventors: Yasuyuki Tsuzawa, Osamu Furukawa, Keibun Harada, Yoichi Uehara
  • Patent number: 4224174
    Abstract: A piezoelectric oxide material having a general formula(1-x)PbTiO.sub.3 -xPb(CO.sub.1/2 W.sub.1/2)O.sub.3where, "x" ranges between 0.01 and 0.20, and 0.5 to 20 atomic % of Pb is replaced by at least one element selected from the group of Ba, Sr and Ca.The piezoelectric oxide material of this composition has a high Curie point, is suitable for use in high frequency regions and can be readily polarized.
    Type: Grant
    Filed: December 29, 1978
    Date of Patent: September 23, 1980
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Hideo Okuma, Takashi Takahashi, Yohachi Yamashita, Osamu Furukawa