Patents by Inventor Kazunori Yamanaka

Kazunori Yamanaka 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: 6367266
    Abstract: A heat insulation chamber according to the present invention is a heat insulation chamber which is made of heat insulating material and forms an inner chamber for accommodating an electronic part. This heat insulation chamber achieves coupling between the electronic part accommodated in the inner chamber formed within a cabinet and the outside of the cabinet by a radio transmission path or a coupling path by static coupling or inductive coupling. A thermostatic chamber and a cryostat according to the present invention comprise the aforementioned heat insulation chamber, a heat exchanger mounted in the heat insulation chamber, and a thermoregulator which maintains the temperature of the inner chamber accommodating the electronic part at an operating temperature of the electronic part through the heat exchanger.
    Type: Grant
    Filed: July 28, 1999
    Date of Patent: April 9, 2002
    Assignee: Fujitsu Limited
    Inventors: Kazuhiko Kobayashi, Kazunori Yamanaka, Akihiko Akasegawa, Yoshiharu Tozawa, Fumihiko Kobayashi, Ichiro Abeno
  • Publication number: 20020038720
    Abstract: The present invention relates to superconductive filter technology. According to the arrangement of the superconductive filter (1), a columnar resonating member (23) having a superconductive material formed on the surface thereof is attached at one of its ends thereof to an inner wall (22) of a filter housing (21) so that a space is interposed between the columnar resonating member and each of connectors (27a, 27b) which are connectable to a signal input/output cables (5a, 5b), respectively. According to this arrangement, heat conduction from the outside can be suppressed as far as possible, and the superconductive condition can be created with stability, with the result that a stable filtering characteristic can be created.
    Type: Application
    Filed: July 26, 2001
    Publication date: April 4, 2002
    Inventors: Manabu Kai, Kazunori Yamanaka, Tsuyoshi Hasegawa, Toru Maniwa
  • Patent number: 6171676
    Abstract: A magnetic recording medium has a substrate of a disk shape having a non-magnetic surface and a through hole formed at the central area of the substrate, and a plurality of dispersed island regions made of magnetic material and directly formed on the non-magnetic surface. The size of each of the island regions is a single magnetic domain size or finer of the magnetic material. The island regions are formed by cohering atoms of a magnetic film formed by sputtering.
    Type: Grant
    Filed: February 13, 1997
    Date of Patent: January 9, 2001
    Assignee: Fujitsu Limited
    Inventors: Ryoichi Mukai, Kazunori Yamanaka, Kazuo Kobayashi
  • Patent number: 6147488
    Abstract: A testing method for a magnetic recording medium which is magnetized measures variation of magnetization with the passage of time and evaluates the magnetic recording medium over its life. The method includes the steps of recording a first pattern at a density to be guaranteed in the magnetic recording medium, the first pattern having a difference between the sum total of areas of +bits and the sum total of areas of -bits, measuring remanence of the first pattern with the passage of time, and evaluating the magnetic recording medium over its life based on a measurement result.
    Type: Grant
    Filed: March 27, 1998
    Date of Patent: November 14, 2000
    Assignee: Fujitsu Limited
    Inventors: Yasuo Bamba, Iwao Okamoto, Kazunori Yamanaka, Wataru Yamagishi
  • Patent number: 5629269
    Abstract: Disclosed is a process for forming a super-conducting film, which a multi-layer metal film (buffer film) is formed at a specific temperature on a ceramic substrate and a superconducting film is formed at a specific temperature on the multi-layer metal film. According to this process, a superconducting film having a high critical temperature can be formed over the ceramic substrate while controlling or suppressing the occurrence of a chemical reaction between the substrate and the superconducting film, and required superconducting performances can be manifested or exhibited.
    Type: Grant
    Filed: October 31, 1994
    Date of Patent: May 13, 1997
    Assignee: Fujitsu Limited
    Inventors: Kazunori Yamanaka, Takuya Uzumaki, Nobuo Kamehara, Koichi Niwa
  • Patent number: 5312803
    Abstract: In an oxide superconducting film wiring, when the line width is reduced, the evaporation of a component during firing becomes so vigorous that it becomes impossible to form a desired single crystal phase, which causes a significant lowering in the properties of the oxide superconducting wiring. This problem can be solved by preventing the evaporation of the evaporable component during the firing. Examples of this include a process wherein plate is placed above the superconductor forming material film wiring pattern on the substrate so as to face each other, the plate comprising a material having no chemical influence on the superconducting wiring, and a pattern of a material containing an evaporable component is arbitrarily formed, a process wherein a pattern having a smaller line width is sandwiched between patterns having a larger line width, and a process wherein the firing atmosphere or the concentration of the evaporable component in the pattern is varied depending upon the line width.
    Type: Grant
    Filed: June 16, 1992
    Date of Patent: May 17, 1994
    Assignee: Fujitsu Limited
    Inventors: Atsushi Tanaka, Kazunori Yamanaka, Nobuo Kamehara, Koichi Niwa
  • Patent number: 5286713
    Abstract: A superconducting circuit board is provided comprising a sintered alumina board containing more than 99% by weight of alumina and an interconnection pattern of an superconducting ceramics formed on the alumina board. Adhesion of the interconnection pattern to the alumina board is improved by an addition of Ti or Si coupling agent to a paste for forming the interconnection pattern. The use of copper powder in place of copper oxide powder as an ingredient forming a superconducting ceramics in the paste is advantageous for printing and obtaining a uniform superconducting ceramic pattern.
    Type: Grant
    Filed: May 21, 1993
    Date of Patent: February 15, 1994
    Assignee: Fujitsu Limited
    Inventors: Hiromitsu Yokoyama, Yoshihiko Imanaka, Kazunori Yamanaka, Nobuo Kamehara, Koichi Niwa, Takuya Uzumaki, Hitoshi Suzuki, Takato Machi
  • Patent number: 5081070
    Abstract: A superconducting circuit board is provided comprising a sintered alumina board containing more than 99% by weight of alumina and an interconnection pattern of an superconducting ceramics formed on the alumina board. Adhesion of the interconnection pattern to the alumina board is improved by an addition of Ti or Si coupling agent to a paste for forming the interconnection pattern. The use of copper powder in place of copper oxide powder as an ingredient forming a superconducting ceramics in the paste is advantageous for printing and obtaining a uniform superconducting ceramic pattern.
    Type: Grant
    Filed: January 30, 1989
    Date of Patent: January 14, 1992
    Assignee: Fujitsu Limited
    Inventors: Hiromitsu Yokoyama, Yoshihiko Imanaka, Kazunori Yamanaka, Nobuo Kamehara, Koichi Niwa, Takuya Uzumaki, Hitoshi Suzuki, Takato Machi
  • Patent number: 5049541
    Abstract: Superconductors of the Bi-Pb-Sr-Ca-Cu-O system and Tl-Pb-Ba-Ca-Cu-O system having a high Tc phase (about 110K and about 125K, respectively, or more) at a high proportion are obtained by adding a calcium compound which forms CaO and a liquid phase at a temperature for firing the superconductors, e.g., Ca.sub.2 PbO.sub.x (x=3 or 4); or by starting form a composition represented by the formula: Bi.sub.2 Pb.sub.(n-1)/2 Sr.sub.2 Ca.sub.n Cu.sub.n+1 O.sub.b, or Tl.sub.2 Pb.sub.(n-1)/2 Ba.sub.2 Ca.sub.n Cu.sub.n+1 Ob where 2.ltoreq.n.ltoreq.10, 5.ltoreq.b.ltoreq.40.5, i.e., at a ratio of Ca:Pb=2:1.
    Type: Grant
    Filed: July 19, 1989
    Date of Patent: September 17, 1991
    Assignee: Fujitsu Limited
    Inventors: Takuya Uzumaki, Kazunori Yamanaka, Nobuo Kamehara, Koichi Niwa
  • Patent number: 4954480
    Abstract: A multi-layer superconducting circuit substrate, including insulating layers, and interconnection patterns of a superconductive ceramic material located between the insulating layers, the patterns of the superconductive ceramic material being connected via through-holes of the superconductive ceramic material, is provided. The patterns of the superconductive ceramic material are preferably encapsulated with a metal of gold, silver, platinum or an alloy thereof.
    Type: Grant
    Filed: April 27, 1988
    Date of Patent: September 4, 1990
    Assignee: Fujitsu Limited
    Inventors: Yoshihiko Imanaka, Takato Machi, Kazunori Yamanaka, Hiromitsu Yokoyama, Nobuo Kamehara, Koichi Niwa