Patents by Inventor Naoki Kodama

Naoki Kodama 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: 4745578
    Abstract: A magnetic bubble memory device comprises contiguous-disk ion-implanted magnetic bubble propagation tracks formed by implanting selectively ions in a magnetic layer which can hold magnetic bubbles. At least one of the disks which form the ion-implanted bubble tracks and each of which may have a circular or square shape, is configured to include a combination of arcs of circles having different curvatures or a combination of sides of squares having different sizes.
    Type: Grant
    Filed: August 21, 1986
    Date of Patent: May 17, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Teruaki Takeuchi, Naoki Kodama, Masatoshi Takeshita, Takashi Toyooka, Ryo Suzuki
  • Patent number: 4744052
    Abstract: A hybrid magnetic bubble memory device includes, magnetic bubble propagation tracks formed of partial ion-implantation and bubble propagation tracks formed of a soft magnetic material pattern. At least one of the junctions between the two type tracks is located on a corner soft magnetic material pattern where the bubble propagation direction is changed, and the hairpin conductor is superposed on the part of the corner pattern under which the magnetic material is not ion-implanted to form ion-implanted propagation tracks.
    Type: Grant
    Filed: June 25, 1986
    Date of Patent: May 10, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Naoki Kodama, Takashi Toyooka, Teruaki Takeuchi, Masatoshi Takeshita, Ryo Suzuki, Shinzo Matsumoto
  • Patent number: 4607349
    Abstract: A highly density magnetic bubble memory device has bubble propagation paths having different pattern periods. The distance between a propagation path having shorter period and a magnetic film for holding magnetic bubbles is made smaller than that between propagation path having longer period and the magnetic film. An insulating layer formed between the propagation path and the magnetic film through another insulating layer has a declining slope having an angle of 60.degree. or less, thereby ensuring steady propagation of the magnetic bubbles along the propagation path.
    Type: Grant
    Filed: July 18, 1983
    Date of Patent: August 19, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Ryo Suzuki, Masatoshi Takeshita, Teruaki Takeuchi, Naoki Kodama, Yutaka Sugita
  • Patent number: 4601013
    Abstract: Disclosed is a magnetic bubble memory device having a first bubble propagation path formed in an ion-implantation pattern and a second bubble propagation path made of permalloy elments in combination. The majority of the area for forming the second propagation path is processed by ion implantation in lower density and to smaller depth than those of ion implantation for forming the first propagation path on the surface of a bubble supporting layer.
    Type: Grant
    Filed: February 27, 1985
    Date of Patent: July 15, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Ryo Suzuki, Yutaka Sugita, Naoki Kodama, Masatoshi Takeshita, Teruaki Takeuchi
  • Patent number: 4589095
    Abstract: A magnetic bubble stretcher comprises a bubble fanning part for propagating a magnetic bubble while gradually stretching the bubble and a bubble propagation part for propagating the stretcher bubble. The bubble fanning and propagation parts include a bubble propagation patterns as fundament elements for stretching or propagating the bubble the bubble propagation patterns in the bubble fanning part are different in shape and/or dimension from the bubble propagation patterns in the bubble propagation part.
    Type: Grant
    Filed: August 1, 1984
    Date of Patent: May 13, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Ryo Suzuki, Teruaki Takeuchi, Masatoshi Takeshita, Naoki Kodama, Yutaka Sugita
  • Patent number: 4589094
    Abstract: A magnetic bubble device includes ion-implanted bubble propagation tracks of meandering cord-like configuration to assure improved bubble propagation characteristic. Amplitude of a region in which inplane magnetization layer is absent or alternatively thickness thereof is smaller than that of other region, as measured in the direction perpendicular to the bubble propagating direction, is not greater than 7/8 of a pitch of the meandering pattern in the bubble propagating direction. The amplitude is more preferably selected so as to meet the condition that 1/4.ltoreq.W/P.ltoreq.3/4 for assuring much stabilized bubble propagating operation.
    Type: Grant
    Filed: July 24, 1984
    Date of Patent: May 13, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Teruaki Takeuchi, Ryo Suzuki, Naoki Kodama, Masatoshi Takeshita, Yutaka Sugita
  • Patent number: 4584668
    Abstract: A magnetic bubble memory device has two types of magnetic bubble propagation tracks. One type of magnetic bubble propagation tracks are formed by implanting ions into a magnetic layer. The other are formed by a soft magnetic material, for example, a permalloy. At least the area where the soft magnetic material is located has a smaller thickness than the other area.
    Type: Grant
    Filed: April 24, 1984
    Date of Patent: April 22, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Teruaki Takeuchi, Ryo Suzuki, Naoki Kodama, Masatoshi Takeshita, Tadashi Ikeda, Toshihiro Sato, Yutaka Sugita
  • Patent number: 4578775
    Abstract: A magnetic bubble memory device is disclosed which is equipped with a minor loop of a magnetic bubble propagation track formed by ion implantation and a major loop or major line of a magnetic bubble propagation track consisting of a soft magnetic film and in which the thickness of an insulating film at at least the junction between the minor loop and the major loop or major line is less than the thickness of insulating film at the major line or major loop.
    Type: Grant
    Filed: June 16, 1983
    Date of Patent: March 25, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Ryo Suzuki, Yutaka Sugita, Teruaki Takeuchi, Naoki Kodama, Masatoshi Takeshita, Hiroshi Umezaki
  • Patent number: 4547865
    Abstract: In a magnetic bubble replicator having a soft magnetic material element for propagating a magnetic bubble along an edge thereof in response to a change in a direction of an external magnetic field and a hairpin-shaped conductor superimposed on the soft magnetic material element, an angle between a slit of the conductor and a propagation path of the magnetic bubble of the soft magnetic material element is set to no less than 90 degrees, preferably 5-85 degrees, and more preferably to 45-60 degrees.
    Type: Grant
    Filed: October 4, 1983
    Date of Patent: October 15, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Naoki Kodama, Masatoshi Takeshita, Ryo Suzuki, Teruaki Takeuchi, Yutaka Sugita
  • Patent number: 4546452
    Abstract: A magnetic bubble device in which a first propagation path having a cyclic shape formed by selectively implanting ions into a magnetic film capable of holding magnetic bubbles and a second propagation path including soft magnetic material elements are arranged on the same chip. A soft magnetic material element having a length in the direction perpendicular to the direction of bubble propagation in the first propagation path which is not less than 2.5 times the period of the first propagation path is included in the junction between the first and second propagation paths.
    Type: Grant
    Filed: October 21, 1983
    Date of Patent: October 8, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Ryo Suzuki, Teruaki Takeuchi, Naoki Kodama, Masatoshi Takeshita, Yutaka Sugita
  • Patent number: 4528645
    Abstract: A magnetic bubble memory device is disclosed in which a magnetic bubble propagation circuit for forming a minor loop is formed by ion implantation, and at least part of a major line or major loop and at least part of connecting portions between the minor loop and the major line or major loop are formed of a film of a soft magnetic material.
    Type: Grant
    Filed: May 5, 1982
    Date of Patent: July 9, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Yutaka Sugita, Ryo Suzuki, Naoki Kodama, Masatoshi Takeshita, Tadashi Ikeda
  • Patent number: 4525808
    Abstract: A hybrid magnetic bubble memory device includes a first magnetic bubble propagation tracks formed of a portion of the boundary between first and second regions of a magnetic medium film having uniaxial anisotropy and adapted to be applied with a magnetic field in a direction perpendicular to the magnetic medium film to generate magnetic bubbles therein, and a second magnetic bubble propagation tracks formed of a soft magnetic material film on the magnetic medium film and connected with the first magnetic bubble propagation tracks. The first region is implanted with ions under ion-implant conditions different from those for the second region, and thus the above boundary is produced.
    Type: Grant
    Filed: March 23, 1984
    Date of Patent: June 25, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Naoki Kodama, Ryo Suzuki, Teruaki Takeuchi, Masatoshi Takeshita, Yutaka Sugita
  • Patent number: 4510231
    Abstract: A conductor pattern and an ion implanting mask are simultaneously formed by photoetching a conductor film through a single photoresist pattern. An area on which a conductor pattern is to be formed is covered with a photoresist, and ions are implanted to a magnetic film using the conductor film portion not convered with the photoresist, to form a magnetic bubble propagation track. The ion implantation mask and the conductor pattern are formed simultaneously through one mask. Accordingly, reduction of accuracy due to an error in mask alignment is prevented and the manufacturing is facilitated.
    Type: Grant
    Filed: January 31, 1983
    Date of Patent: April 9, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Masatoshi Takeshita, Naoki Kodama, Ryo Suzuki, Teruaki Takeuchi, Yutaka Sugita
  • Patent number: 4507755
    Abstract: A magnetic bubble memory device comprises a magnetic bubble propagation track formed by ion implantation. A region enclosed by the propagation track and lightly or shallowly implanted with ions on a condition differing from that for forming the propagation track or not implanted with ions at all is provided with a island-like isolated region heavily or deeply implanted with ions on the same condition as that for forming the propagation track.
    Type: Grant
    Filed: November 10, 1983
    Date of Patent: March 26, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Naoki Kodama, Teruaki Takeuchi, Ryo Suzuki, Masatoshi Takeshita, Yutaka Sugita
  • Patent number: 4494216
    Abstract: Disclosed is a magnetic bubble memory device having a first bubble propagation path formed in an ion-implanted pattern and a second bubble propagation path formed of permalloy elements, both paths being spaced out from each other by a distance larger than or equal to the diameter of the magnetic bubble, and a propagation path connecting structure in which a hairpin-shaped conductor for connecting both propagation paths is disposed between them.
    Type: Grant
    Filed: December 20, 1982
    Date of Patent: January 15, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Ryo Suzuki, Tadashi Ikeda, Masatoshi Takeshita, Naoki Kodama
  • Patent number: 4456975
    Abstract: The magnetic bubble memory device according to this invention comprises an active magnetic bubble memory region formed by implanting ions into a layer of magnetic bubble material, a propagation loop having inner and outer propagation tracks formed by ion implantation so as to surround this region and to propagate captured magnetic bubbles along the circumference of this region, and at least one opening portion provided at the propagation loop so as to propagate magnetic bubbles in the inner propagation track to the outer propagation track.
    Type: Grant
    Filed: February 4, 1982
    Date of Patent: June 26, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Ryo Suzuki, Naoki Kodama, Tadashi Ikeda, Yutaka Sugita
  • Patent number: 4453231
    Abstract: A magnetic bubble memory has a first bubble propagation track formed with an ion-implanted pattern and a second bubble propagation track formed with permalloy members connected to each other to form a storage loop. The arrangement is such that a position of an attractive magnetic pole created in one of the permalloy members coincides with a position of an attractive charged wall appearing in the ion-implanted layer at a junction of the first and second bubble propagation tracks when a driving magnetic field is in a particular range of direction.
    Type: Grant
    Filed: December 3, 1982
    Date of Patent: June 5, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Naoki Kodama, Ryo Suzuki, Masatoshi Takeshita, Yutaka Sugita
  • Patent number: 4163204
    Abstract: The pressure-sensitive resistor comprising an electroconductive elastomer, in which an electroconductive particulate material is dispersed, two electrodes placed on the opposing surfaces of the elastomer, a means for providing a compressive force between the electrodes and a means for adjusting the compressive force, works on a novel principle that the elastomer composite exhibits a positive coefficient in the curve of compression vs. resistance relationship when the compressive force is varied in a region exceeding an inversion point at which the resistance of the elastomer as measured in the direction of compression is minimal. The coefficient in this positive region is smaller than in the ordinary negative region, so that the variable resistance of the resistor can be controlled very delicately together with the decreased contribution of the uncontrollable contact resistance.
    Type: Grant
    Filed: December 26, 1978
    Date of Patent: July 31, 1979
    Assignee: Shin-Etsu Polymer Co., Ltd.
    Inventors: Ryoichi Sado, Akio Nakamura, Naoki Kodama