Patents by Inventor Tsutomu Iikawa

Tsutomu Iikawa 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: 8190378
    Abstract: An element damage determination unit calculates a cumulative value of a damage value using a Manson-Coffin law for a plurality of finite elements of a continuum based on a result of a stress/distortion analyzing process, and determines whether or not the cumulative value of the damage value is equal to or exceeds a threshold. A calculation unit obtains first correspondence information indicating the correspondence between the number of cycles of a load and a growth rate of a crack occurring in the continuum based on the determination result. A Manson-Coffin law change unit changes a Manson-Coffin law based on the first correspondence information and second correspondence information indicating the correspondence between an actual measurement value of the number of cycles of a load applied to the continuum and an actual measurement value of the growth rate of a crack occurring in the continuum at that time.
    Type: Grant
    Filed: October 30, 2008
    Date of Patent: May 29, 2012
    Assignee: Fujitsu Limited
    Inventors: Hidehisa Sakai, Katsufumi Morimune, Masanori Motegi, Tsutomu Iikawa
  • Publication number: 20090187353
    Abstract: An element damage determination unit calculates a cumulative value of a damage value using a Manson-Coffin law for a plurality of finite elements of a continuum based on a result of a stress/distortion analyzing process, and determines whether or not the cumulative value of the damage value is equal to or exceeds a threshold. A calculation unit obtains first correspondence information indicating the correspondence between the number of cycles of a load and a growth rate of a crack occurring in the continuum based on the determination result. A Manson-Coffin law change unit changes a Manson-Coffin law based on the first correspondence information and second correspondence information indicating the correspondence between an actual measurement value of the number of cycles of a load applied to the continuum and an actual measurement value of the growth rate of a crack occurring in the continuum at that time.
    Type: Application
    Filed: October 30, 2008
    Publication date: July 23, 2009
    Applicants: FUJITSU LIMITED, FUJITSU TEN LIMITED
    Inventors: Hidehisa Sakai, Katsufumi Morimune, Masanori Motegi, Tsutomu Iikawa
  • Patent number: 5994144
    Abstract: When adsorbed gas is analyzed after metal, ceramics or metallic salt has been left in an environmental atmosphere for a predetermined period of time, an average concentration of specific gas over a long period of time can be accurately measured with an inexpensive small apparatus. Especially, porous metal or ceramics (transition metal oxide) are excellent in selective adsorption properties for NO.sub.x, porous ceramics (rare earth element oxide) are excellent in selective adsorption properties for CO.sub.2, and a specific chloride such as copper chloride and silver chloride is excellent in selective adsorption properties for SO.sub.2. A test kit accommodating such test pieces in a case, a protective case for the test kit to put the test kit into practical use, an umbrella and a forced air blowing unit are also disclosed.
    Type: Grant
    Filed: January 4, 1994
    Date of Patent: November 30, 1999
    Assignee: Fujitsu Limited
    Inventors: Eiichi Nakajima, Yasuo Udoh, Tsutomu Iikawa, Toshisuke Kitakohji, Teruo Motoyoshi, Takashi Furusawa, Shiori Yamazaki, Masao Nakayama, Michiko Satoh, Shigeru Fukushima, Mayumi Itabashi
  • Patent number: 5985213
    Abstract: When adsorbed gas is analyzed after metal, ceramics or metallic salt has been left in an environmental atmosphere for a predetermined period of time, an average concentration of specific gas over a long period of time can be accurately measured with an inexpensive small apparatus. Especially, porous metal or ceramics (transition metal oxide) are excellent in selective adsorption properties for NO.sub.x, porous ceramics (rare earth element oxide) are excellent in selective adsorption properties for CO.sub.2, and a specific chloride such as copper chloride and silver chloride is excellent in selective adsorption properties for SO.sub.2. A test kit accommodating such test pieces in a case, a protective case for the test kit to put the test kit into practical use, an umbrella and a forced air blowing unit are also disclosed.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: November 16, 1999
    Assignee: Fujitsu Limited
    Inventors: Eiichi Nakajima, Yasuo Udoh, Tsutomu Iikawa, Toshisuke Kitakohji, Teruo Motoyoshi, Takashi Furusawa, Shiori Yamazaki, Masao Nakayama, Michiko Satoh, Shigeru Fukushima, Mayumi Itabashi
  • Patent number: 5934663
    Abstract: Rubber rollers for carrying media, comprising a blend of urethane rubber and silicone rubber, and an apparatus equipped therewith. A rubber roller abrasion evaluating tester provided with means for carrying a medium to be carried while in contact with rubber rollers to be evaluated, and means for forcefully causing slippage of the carried medium by a prescribed distance on the rollers. A method of selecting a medium to be carried which has a prescribed abrasive strength, by abrading a carried medium under a constant weight using an abrading material and calculating the rate of the abrasion of the carried medium.
    Type: Grant
    Filed: December 29, 1994
    Date of Patent: August 10, 1999
    Assignee: Fujitsu Limited
    Inventors: Kazumasa Saito, Takao Shinohara, Tsutomu Iikawa
  • Patent number: 5750406
    Abstract: There is provided a test piece by which NO.sub.x, present in an environment may be visually observed apart from the influence of other gases, and with which qualitative and quantitative analysis may be performed. The test piece has a layered structure prepared by vacuum deposition a metal thin-film (Ag, Pt, Au, etc.) on a metal substrate (Cu, Zn, etc.). The rough amounts of NO.sub.x, SO.sub.x and NH.sub.3 in the environment are determined on the basis of the corrosion products (nitrates, etc.) produced when NO.sub.x, SO.sub.x and NH.sub.3 are collected after the test piece has been exposed to the environment for a prescribed period of time.
    Type: Grant
    Filed: May 1, 1995
    Date of Patent: May 12, 1998
    Assignee: Fujitsu Limited
    Inventors: Eiichi Nakajima, Yasuo Udoh, Tsutomu Iikawa, Toshisuke Kitakohji, Teruo Motoyoshi, Takashi Furusawa, Shiori Yamazaki, Masao Nakayama, Michiko Satoh, Shigeru Fukushima, Mayumi Itabashi
  • Patent number: 4941918
    Abstract: A magnesium-based composite material having improved mechanical strength, and in particular an improved modulus of elasticity, and a relatively low density. The material is provided by pressing and sintering a mixture of magnesium or magnesium-based alloy particles or a particulate combination of magnesium particles and particles of one or more additional metals, with a reinforcement additive of boron, or boron-coated B.sub.4 C, Si.sub.3 N.sub.4, SiC, Al.sub.2 O.sub.3 or MgO particles.
    Type: Grant
    Filed: December 12, 1988
    Date of Patent: July 17, 1990
    Assignee: Fujitsu Limited
    Inventors: Eiji Horikoshi, Tsutomu Iikawa, Takehiko Sato
  • Patent number: 4925502
    Abstract: The iron-cobalt type soft magnetic material contains 35% to 60% by weight of cobalt, 0.03% to 2.0% by weight of aluminum, the remainder being iron, and is prepared by powder metallurgy.
    Type: Grant
    Filed: September 7, 1988
    Date of Patent: May 15, 1990
    Assignee: Fujitsu Limited
    Inventors: Wataru Yamagishi, Tsutomu Iikawa
  • Patent number: 4760240
    Abstract: A process for laser welding a cover and a casing, each made of aluminum or an aluminum-based alloy, via a nickel layer plated thereon, thereby forming a package for electronic devices, the process comprising the steps of: boring holes in sides of the casing, thereby providing holes through which input/output and source terminals can be inserted and be soldered hermetically to the casing; plating a nickel layer on the surface of the casing; mounting electronic devices in the casing and forming necessary connections between the devices and the terminals; and, welding the cover and the casing together by pulsed YAG laser beam, thereby forming a weld zone containing 1.5 to 10.0% of nickel by weight, and sealing the cover and the casing hermetically.
    Type: Grant
    Filed: February 9, 1987
    Date of Patent: July 26, 1988
    Assignee: Fujitsu Limited
    Inventors: Tsutomu Iikawa, Takeaki Sakai, Isao Kawamura, Katsuhide Natori, Takeshi Nagai, Shigeki Okamoto