Patents by Inventor Yoshikazu Imai

Yoshikazu Imai 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: 6217997
    Abstract: According to a ceramic fiber reinforced ceramic matrix composite material of the present invention, a ceramic fiber reinforced ceramic matrix composite material 1 comprises a composite ceramic matrix, and a preform 5 resulting from a fiber bundle 3 obtained by bundling a plurality of ceramic fibers 2 and disposed therein, and is characterized in that a first ceramic matrix M1 is formed in an inner space of the fiber bundle 3 and at a region adjacent to an outer periphery thereof, and a second ceramic matrix M2 is formed in an inner space of the preform 5 and at an outer peripheral region thereof, the space and region of the preform being defined except for those of the fiber bundle. Also characteristically, ceramic fibers are compositely disposed in a fiber volume fraction (Vf) of greater than 10% in a reaction-sintered ceramic matrix.
    Type: Grant
    Filed: March 11, 1997
    Date of Patent: April 17, 2001
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shoko Suyama, Tsuneji Kameda, Masahiro Asayama, Nagatoshi Okabe, Hideyuki Hirata, Hiroshi Ichikawa, Yoshikazu Imai, Shiro Mitsuno, Satoshi Miyazaki
  • Patent number: 5234675
    Abstract: An organosilicon high molecular compound having a skeleton of silicon and carbon or a compound obtained by polymerization of an organometallic compound and the organosilicon high molecular compound is melted into a fiber, then the fiber is antimelt-treated in an oxidizing atmosphere, and the antimelt-treated yarns are thereafter heated in an atmosphere of inert gas to obtain a fiber of silicon carbide containing 2 to 20% by volume of oxygen. This fiber is further sintered in an atmosphere of inert gas at a temperature of 1400 to 2100 deg. C. and a pressure of 300 to 3000 kg/cm.sup.2. A sintered body of silicon carbide having an excellent bending strength is obtained without the use of a sintering agent or a binder. A fiber of silicon carbide having a predetermined oxygen content and a thin amorphous carbon layer thereon is obtained from the starting fiber by antimelt-treating and then heating in an atmosphere of a mixture of an inert gas and a hydrocarbon gas.
    Type: Grant
    Filed: October 1, 1991
    Date of Patent: August 10, 1993
    Assignee: Nippon Carbon Co. Ltd.
    Inventors: Hiroshi Ichikawa, Yoshikazu Imai
  • Patent number: 4877643
    Abstract: A process for producing a preformed wire from silicon carbide fiber-reinforced aluminum, which comprises silicon dipping a bundle of silicon carbide fibers for a period of 60 seconds or shorter in a melt of a eutectic alloy composed of aluminum and 5.0 to 7.0 wt. % of nickel added thereto which melt is kept at or below the liquidus temperature of the melting point thereof plus 50.degree. to impregnate said fiber bundle with said alloy.
    Type: Grant
    Filed: December 30, 1988
    Date of Patent: October 31, 1989
    Assignee: Director General Agency of Industrial Science and Technology
    Inventors: Toshikatsu Ishikawa, Katsuya Tokutomi, Yoshikazu Imai
  • Patent number: 4779563
    Abstract: A preform wire for fiber reinforced metal composite consisting of a metal/silicon carbide fiber composite material is light in weight and excellent in strength and elasticity, and can be easily obtained by impregnating a silicon carbide fiber bundle with a molten metal which is kept vibrated by means of an ultrasonic wave vibration apparatus having a hole for cooling water or a cooling-water jacket located at the node of the half-wavelength of the ultrasonic wave created by the vibration apparatus.
    Type: Grant
    Filed: November 20, 1986
    Date of Patent: October 25, 1988
    Assignee: Agency of Industrial Science & Technology
    Inventors: Toshikatsu Ishikawa, Haruo Teranishi, Yoshikazu Imai, Yoichi Nagata
  • Patent number: 4769195
    Abstract: A method for manufacturing a silicon carbide fiber reinforced glass composite, which comprises either dipping silicon carbide fibers in molten glass in a tank, the molten glass being given wave vibration of 10-30 KHz by a supersonic vibrator provided with a cooling means to unravel the silicon carbide fibers and have the molten glass permeated therebetween, or plasma melt ejecting glass powder onto silicon carbide fibers to obtain a silicon carbide fiber/glass preform, molding the preform into a predetermined form and then subjecting the molded preform to thermal molding thereby to manufacture the silicon carbide fiber reinforced glass composite in the form of a molding.
    Type: Grant
    Filed: July 22, 1987
    Date of Patent: September 6, 1988
    Assignee: Nippon Carbon Co. Ltd.
    Inventors: Toshikatsu Ishikawa, Haruo Teranishi, Hiroshi Ichikawa, Yoshikazu Imai, Masanobu Umezawa
  • Patent number: 4717589
    Abstract: A method for manufacturing a silicon carbide fiber reinforced glass composite, which comprises either dipping silicon carbide fibers in molten glass in a tank, the molten glass being given wave vibration of 10-30 KHz by a supersonic vibrator provided with a cooling means to unravel the silicon carbide fibers and have the molten glass permeated therebetween, or plasma melt ejecting glass powder onto silicon carbide fibers to obtain a silicon carbide fiber/gass preform, molding the preform into a predetermined form and then subjecting the molded preform to thermal molding thereby to manufacture the silicon carbide fiber reinforced glass composite in the form of a molding.
    Type: Grant
    Filed: October 9, 1986
    Date of Patent: January 5, 1988
    Assignee: Nippon Carbon Co. Ltd.
    Inventors: Toshikatsu Ishikawa, Haruo Teranishi, Hiroshi Ichikawa, Yoshikazu Imai, Masanobu Umezawa
  • Patent number: 4649060
    Abstract: A preform wire for fiber reinforced metal consisting of a metal/silicon carbide fiber composite material is light in weight and excellent in strength and elasticity, and can be easily obtained by impregnating a silicon carbide fiber bundle with a molten metal which is kept vibrated by means of an ultrasonic wave vibration apparatus having a cooling means.
    Type: Grant
    Filed: March 15, 1985
    Date of Patent: March 10, 1987
    Assignee: Agency of Industrial Science & Technology
    Inventors: Toshikatsu Ishikawa, Haruo Teranishi, Yoshikazu Imai, Yoichi Nagata
  • Patent number: 4507354
    Abstract: An electromagnetic wave absorber comprising an electromagnetic wave absorbing layer consisting essentially of silicon carbide fibers, which layer may be applied to a metal plate. The wave absorber comprising the absorbing layer-applied metal plate exerts wave absorption expressed in terms of a wave attenuation which is at least 10 dB higher than the inherent attenuation caused by reflection of the wave by the absorbing layer-free original metal plate, the wave used being one which has a frequency of 8-16 GHz. Further, the silicon carbide fibers may be made into woven cloths, mat felts or the like which are laminated together and then composited with a synthetic resin or ceramics to prepare the wave absorbing layer.
    Type: Grant
    Filed: March 21, 1983
    Date of Patent: March 26, 1985
    Assignee: Nippon Carbon Co., Ltd.
    Inventors: Toshikatsu Ishikawa, Hiroshi Ichikawa, Yoshikazu Imai, Tokuji Hayase, Yoichi Nagata
  • Patent number: 4397482
    Abstract: Construction of an anchor sash for use in a seatbelt system in which one end of an occupant restraining webbing is secured to a door and the webbing is automatically placed over an occupant in accordance with the opening and closing of the door. An anchor plate secured to one end of the webbing is in turn secured to a support base portion obtained by deforming a door sash and extends into a compartment of the vehicle, whereby the door sash has a satisfactorily mechanical strength despite the door sash has a small outside dimension. The anchor plate is supported to the vehicle body by a combination of an anchor pin having an enlarged head and a bracket having a receiving groove being open in the outward direction of the vehicle.
    Type: Grant
    Filed: April 29, 1981
    Date of Patent: August 9, 1983
    Assignee: Toyota Jidosha Kogyo Kabushiki Kaisha
    Inventors: Hisashi Ogawa, Yoshikazu Imai
  • Patent number: 4392673
    Abstract: A raised arm structure protruding inwardly on a vehicle door has a longitudinally extending slit through the undersurface thereof, and through the slit, a movable belt guide within the arm structure slidably holds an intermediate portion of an occupant restraining webbing from within the arm structure, whereby a part of the webbing held by the movable belt guide is out of sight from above and under the arm structure.
    Type: Grant
    Filed: October 3, 1980
    Date of Patent: July 12, 1983
    Assignee: Toyota Jidosha Kogyo Kabushiki Kaisha
    Inventors: Ichiro Suzuki, Jun Yasumatsu, Yoshikazu Imai, Masanao Motonami
  • Patent number: 4372580
    Abstract: An automatic seatbelt system for automatically fastening an outer webbing and an inner webbing to an occupant upon being seated, wherein opposite ends of the outer webbing are engaged with the upper and lower portions of a vehicle door, respectively, the base portion of the inner webbing is wound into a retractor provided at substantially the central portion of the vehicle, and, in an emergency of a vehicle, the intermediate portion of the inner webbing is directly locked, so that the inner webbing can be prevented from being wound out of the retractor.
    Type: Grant
    Filed: December 29, 1980
    Date of Patent: February 8, 1983
    Assignee: Toyota Jidosha Kogyo Kabushiki Kaisha
    Inventors: Masanao Motonami, Hisashi Ogawa, Yoshikazu Imai