Patents by Inventor Junichi Honda

Junichi Honda 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: 6452892
    Abstract: First and second magnetic layers are laminated though a tunnel barrier layer, wherein a region is formed in which change in a magnetic resistance ratio with respect to change in a voltage applied in such a manner that the second magnetic layer has a lower potential as compared with the potential of the first magnetic layer is smaller than change in a magnetic resistance ratio with respect to change in a voltage applied in such a manner that the second magnetic layer has a higher potential as compared with the potential of the first magnetic layer. Voltage is applied to the magnetic tunnel device in such a manner that the potential of the second magnetic layer is lower than that of the first magnetic layer so that dependency of the magnetic resistance ratio on the voltage is reduced. Thus, a stable tunnel current flows.
    Type: Grant
    Filed: May 1, 2000
    Date of Patent: September 17, 2002
    Assignee: Sony Corporation
    Inventors: Seiji Kumagai, Junichi Honda, Yoshito Ikeda
  • Patent number: 6136431
    Abstract: The present invention provides a soft magnetic thin film having a high magnetic permeability and showing a magnetic isotropy which can be obtained without a complicated production procedure, and a magnetic head using this soft magnetic thin film.The soft magnetic thin film has a composition expressed as Fe.sub.a M.sub.b N.sub.c O.sub.d wherein M represents at least one of Ta, Zr, Hf, Nb, and Ti; and a, b, c, and d represent atomic percents which are defined as follows: 71 .ltoreq.a.ltoreq.85; 6.ltoreq.b.ltoreq.15; 9.ltoreq.c.ltoreq.16; and 1.ltoreq.d.ltoreq.3.5.
    Type: Grant
    Filed: April 28, 1998
    Date of Patent: October 24, 2000
    Assignee: Sony Corporation
    Inventors: Yoshihiko Inoue, Junichi Honda, Fusashige Tokutake
  • Patent number: 5939186
    Abstract: A magnetic head having a laminated magnetic film in which crystal orientation of precipitated small crystal particles can be controlled and the soft magnetic characteristic in the thickness of the laminated magnetic film can easily be controlled. The magnetic head has the laminated magnetic film formed by laminating thin magnetic layers, each having a composition as Fe.sub.x M.sub.y N.sub.z, and metal layers. The laminated magnetic film is subjected to heat treatment so that metal atoms forming the metal layers are diffused into the thin magnetic films. Thus, the laminated magnetic film contains small crystal particles of .alpha.Fe, the direction of crystal of which is controlled by the diffused metal atoms. Therefore, the laminated magnetic film has an excellent soft magnetic characteristic also in the direction of the thickness thereof.
    Type: Grant
    Filed: January 28, 1997
    Date of Patent: August 17, 1999
    Assignee: Sony Corporation
    Inventors: Fusashige Tokutake, Junichi Honda, Yoshihiko Inoue
  • Patent number: 5936815
    Abstract: A thin film type magnetic head that electromagnetic conversion efficiency is improved by making gradually magnetic resistance larger with approaching to a magnetic gap can be provided. There is disclosed a magnetic head including a pair of magnetic core half members having nonmagnetic substrates and magnetic metal films formed on the nonmagnetic substrates and a coil formed at a concave part by a thin film forming process, the pair of magnetic core half members being jointed to each other opposite to each other through a magnetic gap formed between the respective magnetic metal films, the concave part formed on the surface formed by joining at least one of the magnetic metal films and the other magnetic metal film, wherein assistant cores consisting of magnetic materials are joined on the side of the surface by joining a pair of nonmagnetic substrates and the magnetic metal films are formed connected with the assistant cores.
    Type: Grant
    Filed: September 16, 1997
    Date of Patent: August 10, 1999
    Assignee: Sony Corporation
    Inventors: Seiji Kumagai, Junichi Honda, Norikatsu Fujisawa, Kyu Kanno
  • Patent number: 5867887
    Abstract: A method of manufacturing a magnetic head by bonding a pair of magnetic cores to each other, wherein a residual stress in the magnetic cores upon bonding them together is controlled so that a permeability of the magnetic cores in the vicinity of a magnetic recording medium sliding surface of the magnetic cores may become maximum. Accordingly, the residual stress in the magnetic cores is controlled so that the permeability of the magnetic cores may surely become maximum after forming the magnetic head, thereby ensuring a superior reproduction efficiency of the magnetic head.
    Type: Grant
    Filed: November 12, 1996
    Date of Patent: February 9, 1999
    Assignee: Sony Corporation
    Inventors: Seiji Kumagai, Masatoshi Hayakawa, Yoshito Ikeda, Junichi Honda
  • Patent number: 5862023
    Abstract: A magnetic head is disclosed which has a metal magnetic film formed by first stacking Fe--M--N magnetic thin film layers and precious metal layers such as Pt layers to form a multilayer film and then stacking such multilayer films via an insulating film so that the reproduction output is improved to make the magnetic head suitable for recording on and reproduction from a magnetic recording medium having a large coercive force, such as, a so-called metal tape. On gap forming surfaces of a pair of magnetic core halves, a multilayer structure formed by first forming a multilayer film by stacking magnetic thin film layers having composition of Fe.sub.x M.sub.y N.sub.z (with M being at least one selected from Ta, Zr, Hf, Nb, Ti, Mo and W, and x, y and z indicating atomic percentage and holding relations of 71.ltoreq.x.ltoreq.85, 6.ltoreq.y.ltoreq.15, and 9.ltoreq.z.ltoreq.
    Type: Grant
    Filed: April 23, 1997
    Date of Patent: January 19, 1999
    Assignee: Sony Corporation
    Inventors: Yoshihiko Inoue, Junichi Honda, Fusashige Tokutake
  • Patent number: 5737154
    Abstract: A rotary magnetic head apparatus is provided which is capable of reliably supplying DC power for driving to an active-type reproducing head provided within a rotary drum and which is capable of taking the reproductive output signal of the active-type head to the outside of the drum. The rotary magnetic head apparatus includes a fixed drum, a rotary drum which is rotatable with respect to the fixed drum, an active-type reproducing head, disposed on the rotary drum, for reproducing information from a magnetic tape, a constant-current circuit, disposed on the rotary drum, for supplying a constant current for driving the head to the active-type reproducing head, a noncontact signal transmission device for taking the reproductive output signal which is output when the active-type reproducing head reproduces information from the magnetic tape to the outside of the rotary drum, and a sliding-type contact device for supplying external DC power to the constant-current circuit.
    Type: Grant
    Filed: June 18, 1996
    Date of Patent: April 7, 1998
    Assignee: Sony Corporation
    Inventors: Seiji Kumagai, Masatoshi Hayakawa, Hiroshi Morita, Norikatsu Fujisawa, Junichi Honda, Yuji Nakano
  • Patent number: 5708543
    Abstract: A magnetic head according to the present invention can generate excellent readout output even with a reduced track width by controlling the stress applied to the half magnetic cores from the glass. The magnetic head comprises a pair of magnetic cores made of ferromagnetic oxide, at least one of which has a groove for a coil and which are bonded together with the glass with a gap material in-between, wherein the coefficient of thermal expansion of the glass to bond magnetic cores together is smaller than that of the ferromagnetic oxide by 20.times.10.sup.-7 to 35.times.10.sup.-7 per degree Celsius.
    Type: Grant
    Filed: May 30, 1996
    Date of Patent: January 13, 1998
    Assignee: Sony Corporation
    Inventors: Junichi Honda, Norikatsu Fujisawa
  • Patent number: 5663857
    Abstract: A magnetic head comprising a pair of magnetic core halves each having a magnetic core film sandwiched between a pair of non-magnetic substrates, said magnetic core halves being abutted to each other with the end faces of the magnetic core films facing each other, with a magnetic gap being defined in an interface of abutment of said magnetic core films, wherein the magnetic core film is of a laminated magnetic film structure comprising a plurality of laminated magnetic film units laminated with insulating films in-between. Each laminated magnetic film unit in turn comprises a plurality of magnetic films with non-magnetic films in-between, with the magnetic films being magnetostatically connected to one another at film ends. By employing the laminated magnetic film unit for the magnetic core film, it becomes possible to markedly increase the magnetic permeability in a direction normal to the gap depth when anisotropy is applied in the gap depth direction.
    Type: Grant
    Filed: August 8, 1996
    Date of Patent: September 2, 1997
    Assignee: Sony Corporation
    Inventors: Tatsuo Kumura, Fusashige Tokutake, Akira Urai, Junichi Honda, Hideaki Ojima
  • Patent number: 5515222
    Abstract: In a magnetic head having a pair of magnetic cores defining a magnetic gap in-between, a side of each magnetic core facing a recording medium is formed of a single-crystal ferrite, with the remaining portions of each magnetic core being formed of poly-crystal ferrite. The surface of the magnetic core facing the recording medium and the abutment surface of the magnetic core are the {100} plane and the {100} plane of the single-crystal ferrite, respectively. The magnetic head has excellent abrasion resistance and electro-magnetic conversion characteristics.
    Type: Grant
    Filed: April 29, 1994
    Date of Patent: May 7, 1996
    Assignee: Sony Corporation
    Inventors: Seiji Kumagai, Junichi Honda, Yoshitomo Ito, Masatoshi Hayakawa, Toru Matsunaga, Mineo Yorizumi, Yoshito Ikeda
  • Patent number: 5475551
    Abstract: A magnetic head has a pair of magnetic core substrates formed of an oxide magnetic material, at least one of the magnetic core substrates having a gap film formed on an abutment surface thereof, the pair of magnetic core substrates being abutted to each other on the gap film as abutment surfaces, having a magnetic gap formed between them. The gap film is formed of platinum, the platinum group, or an alloy consisting mainly of platinum or the platinum group. The pair of magnetic core substrates are bonded to each other to be integrated into one unit by a non-magnetic glass. The magnetic gap has a track width of not greater than 50 .mu.m. The gap film has a thickness of not greater than 150 nm.
    Type: Grant
    Filed: July 8, 1994
    Date of Patent: December 12, 1995
    Assignee: Sony Corporation
    Inventors: Junichi Honda, Seiji Kumagai, Norikatsu Fujisawa, Masatoshi Hayakawa, Masahiro Kikkawa, Miho Suzuki
  • Patent number: 4640001
    Abstract: Solar cell manufacturing method in which a silicon wafer is coated with an antireflection coating of silicon nitride by means of plasma CVD deposition with the silicon wafer kept at a temperature between 250.degree. C. and 600.degree. C. The coating of silicon nitride at such a high temperature results in a decrease in the recombination speed of the minority carriers produced in the silicon wafer during time of light incidence. The conversion efficiency is thus increased to a value ranging from 11.04% to 12.56%.
    Type: Grant
    Filed: December 20, 1984
    Date of Patent: February 3, 1987
    Assignee: Japan Solar Energy Co., Ltd.
    Inventors: Sakae Koiwai, Keizo Asaoka, Katsuhiko Shirasawa, Hiroyuki Watanabe, Junichi Honda
  • Patent number: 4224081
    Abstract: One or more solar cells are sandwiched by a pair of glass laminations substantially transparent to (i.e., essentially transmissive of) the impinging light, thereby avoiding output drop which may occur due to temperature increase by passing of the impinging light therethrough. A thermoplastic or thermosetting type filler, for example, polyvinylbutyral or a silicone resin is used to fill the cavity surrounded by the glass laminations for accommodating the solar cells therein, while serving as an embedding and potting compound to provide resilient environmental protection for the solar cells. Any room temperature vulcanizing type filler may be used.
    Type: Grant
    Filed: November 26, 1975
    Date of Patent: September 23, 1980
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Koichi Kawamura, Junichi Honda, Junichirou Hisatomi, Junichiro Shigemasa
  • Patent number: 3955809
    Abstract: A spiral spring arrangement consists essentially of two spiral springs. The spring arrangement comprises an immovable member, a rotatable shaft, and a rotatively movable member. One of the spiral springs has one end connected to the immovable member and the other end to the rotatable shaft. The other spiral spring has one end connected to the rotatable shaft and the other end to the rotatively movable member. The rotatably movable member serves as the point acting on the spiral springs. The two spiral springs are in a serial relationship, thus reducing the spring constant against rotation.
    Type: Grant
    Filed: May 23, 1974
    Date of Patent: May 11, 1976
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kuniyoshi Hara, Junichi Honda