Patents by Inventor Nobumasa Nirasawa

Nobumasa Nirasawa 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: 6905646
    Abstract: A method of producing a synthetic resin rod (wire), comprising: an extruding step of extruding a synthetic resin rod; a pre-cooling step of spraying a cooling medium on the rod to pre-cool the rod extruded down to a temperature (T° C.) satisfying the following condition: T?{(a softening point of the synthetic resin)+5} [° C.]; and a main cooling step of letting the rod thus pre-cooled pass through water to cool the rod.
    Type: Grant
    Filed: March 23, 2000
    Date of Patent: June 14, 2005
    Assignee: Sumitomo Electric Industries, Ltd
    Inventors: Ryoei Oka, Nobumasa Nirasawa, Saburo Yoshimura, Hironori Matsumoto
  • Patent number: 5661836
    Abstract: In an optical cable according to the present invention, a grooved spacer has a plurality of grooves in its circumference, and the cutting direction of the grooves is inverted at predetermined periods. Optical fibers are received in the respective grooves. On the circumference of the grooved spacer, a linear member is provided around the grooved spacer along the longitudinal direction of the optical cable at a predetermined period. The linear member is fixed to the grooved spacer by welding or bonding in the portions where they touch the outer circumferences of the grooved spacer so as to restrain the optical fibers. The linear member restraining the optical fiber to be taken out are cut in positions above the groove in which the optical fiber is received so that the required optical fiber can be taken out.
    Type: Grant
    Filed: February 20, 1996
    Date of Patent: August 26, 1997
    Assignees: Sumitomo Electric Industries, Ltd., Nippon Telegraph and Telephone Corporation
    Inventors: Hiroaki Sano, Hiroki Ishikawa, Shigeru Tanaka, Nobumasa Nirasawa, Kenji Morita, Osamu Kawata, Kazuo Hogari
  • Patent number: 5315813
    Abstract: An apparatus for, and method of manufacturing an optical fiber cable whereby stable transmission characteristics, such as length and tension, are maintained throughout a specified length of the cable. A slotted rod having spiral grooves formed longitudinally on the surface thereof is hauled by a hauling device, optical fibers or optical fiber ribbons are inserted into the spiral grooves, and a binding is applied onto the outer surface of the slotted rod to form the basis for an optical fiber cable stranding. The optical cable stranding with the optical fibers or the like inserted in the spiral grooves and with the binding applied thereon is wound around a guide wheel, thereby maintaining stable transmission characteristics throughout a specified length of the cable, and then further hauled. The guide wheel is rotatable about a rotary axis perpendicular to the hauling direction of the slotted rod.
    Type: Grant
    Filed: July 2, 1992
    Date of Patent: May 31, 1994
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yasushi Ito, Nobumasa Nirasawa
  • Patent number: 4767184
    Abstract: An optical fiber cable in which plural optical fibers are joined in a flat assembly. Each assembly is coated with a water-swelling resin, stacked with other such flat assemblies and fitted in a spiral groove of a spacer. A tape is wound around the so-fitted spacer.
    Type: Grant
    Filed: April 7, 1987
    Date of Patent: August 30, 1988
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Ichiro Ogasawara, Nobumasa Nirasawa, Akira Nishimura