Patents by Inventor Sakan Takai

Sakan Takai 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: 4754429
    Abstract: A cassette type magnetic bubble memory comprise a bubble memory device including a bubble memory chip and lead terminals; a connector having contacts for electrically connecting the bubble memory device to an outside unit; thin flexible printed substrates for electrically connecting the contacts of the connector to the lead terminals of the bubble memory device; and a cassette case for accommodating therein the bubble memory device, the connector, and the printed substrates. The cassette case has inner walls. Some parts of the inner walls are in contact with at least some parts of an outer face of the bubble memory device to retain the device in the cassette case so that the majority of the outer face of the device is spaced from the majority of the inner walls of the cassette case. The bubble memory device and the connector are arranged in displaced positions along a plane common to the longitudinal direction of insertion of the cassette case into a bubble memory control unit.
    Type: Grant
    Filed: May 9, 1985
    Date of Patent: June 28, 1988
    Assignee: Fujitsu Limited
    Inventors: Kouei Kashiro, Toshiaki Sukeda, Satoru Imai, Sakan Takai, Harumi Maegawa
  • Patent number: 4710895
    Abstract: A magnetic bubble memory module containing a magnetic bubble memory device and its analog peripheral circuits mounted on a substrate, having outer input/output lead terminals, allowing the module to be mounted on a conventional printed circuit board instantaneously with other electronic elements. Lead terminals of the magnetic bubble memory device are protected by a protection means of an insulator such as plastic material, so that the magnetic bubble memory device is protected from the electrostatic discharge damage caused by the touching of a charged body such as human fingers. This results in high reliability and high production yield of the magnetic bubble memory apparatus.
    Type: Grant
    Filed: May 7, 1985
    Date of Patent: December 1, 1987
    Assignee: Fujitsu Limited
    Inventors: Harumi Maegawa, Sakan Takai, Toshiaki Sukeda, Shoji Irie, Shoichi Kobata
  • Patent number: 4549282
    Abstract: A magnetic bubble memory system includes a plurality of magnetic bubble devices, each of which has at least one minor loop for storing magnetic bubbles, at least one information transfer gate and replicator. Also included in the system are at least one page-allocation designating circuit provided for a corresponding magnetic bubble device for designating single-page or multi-page mode of access and a control-signal generating circuit which outputs a signal controlling the information transfer and replicator gates in cooperation with the output from the page-allocation designating circuit.
    Type: Grant
    Filed: December 6, 1983
    Date of Patent: October 22, 1985
    Assignee: Fujitsu Limited
    Inventors: Sakan Takai, Takenori Iida, Keiichi Kaneko
  • Patent number: 4485458
    Abstract: A magnetic bubble cassette comprising bubble memory devices mounted on a printed board in a case and a connector for connecting said bubble memory devices to an external apparatus, including through another bubble memory device for driving said bubble memory device. The connecting portion of said connector that is connected to the external apparatus is arranged on a peripheral wall parallel to the insertion direction of said cassette into said external apparatus. This configuration, allowing a plurality of magnetic bubble memory devices to be disposed in the cassette, increases memory capacity while improving handling of the cassettes.
    Type: Grant
    Filed: June 17, 1981
    Date of Patent: November 27, 1984
    Assignee: Fujitsu Limited
    Inventors: Toshiaki Sukeda, Harumi Maekawa, Sakan Takai
  • Patent number: 4432068
    Abstract: A method of controlling a magnetic bubble memory device comprising a rotating field generation coil for applying the rotating field to a magnetic pattern formed on a magnetic bubble memory chip and transferring the magnetic bubble along the magnetic pattern. A bubble memory device controlled by the method of the present invention, is capable of operating in a wider ambient temperature range by heating the chip through heat generation realized by applying a heating current to the rotating field generation coil while the magnetic bubble transfer control is not carried out.
    Type: Grant
    Filed: September 2, 1981
    Date of Patent: February 14, 1984
    Assignee: Fujitsu Limited
    Inventors: Sakan Takai, Toshiaki Sukeda
  • Patent number: 3952292
    Abstract: Out-of-phase currents of trapezoidal or triangular waveshape are supplied to the drive coils of a magnetic bubble device. The induced magnetic field of the magnetic bubble device rotates at a uniform constant speed and has a linearly varying locus.
    Type: Grant
    Filed: December 10, 1974
    Date of Patent: April 20, 1976
    Assignee: Fujitsu Ltd.
    Inventors: Masahiro Komatsu, Sakan Takai, Harumi Maegawa, Masaki Takasu