Patents by Inventor Noritoshi Saito

Noritoshi Saito 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: 5463518
    Abstract: A magnetic head has a superconducting quantum interference device having a ring made of a superconductive material including a Josephson junction which links to a magnetic flux generated by a magnetic recording medium, and a magnetic pole for guiding the magnetic flux generated by the magnetic recording medium or the ring made of a superconductive material arranged in parallel to a plane of the magnetic recording medium so that the magnetic flux generated by the magnetic recording medium flows into a through-hole of the ring. A magnetic recording and reproducing apparatus includes such a magnetic head, a winding to which a reproduced signal from the magnetic head is applied and the superconductive ring including the Josephson junction arranged such that the magnetic flux generated by the winding flows thereto.
    Type: Grant
    Filed: March 22, 1991
    Date of Patent: October 31, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Shigekazu Otomo, Noriyuki Kumasaka, Kazuo Shiiki, Takeo Yamashita, Noritoshi Saito, Yoshinobu Tarutani
  • Patent number: 4972285
    Abstract: An amorphous magnetic alloy of Co-Nb-Zr system contains Co, Nb and Zr and has a composition which falls, in terms of atomic percent, within the region defined by straight lines connecting, in a ternary composition diagram assuming the total of contents of these three elements to be 100, a point (81% Co, 14% Nb, 5 Zr), a point (88% Co, 9% Nb, 3% Zr), a point (86.5% Co, 12.5% Nb, 1% Zr) and a point (81% Co, 18% Nb, 1% Zr). Disclosed also is a magnetic head having a core at least a part of which is constituted by this amorphous magnetic alloy. This magnetic head, when used in combination with a metal powder tape having a high coercive force, provides a remarkably increased recording-reproducing output.
    Type: Grant
    Filed: July 12, 1988
    Date of Patent: November 20, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Shigekazu Otomo, Noriyuki Kumasaka, Hideo Fujiwara, Shinji Takayama, Takeo Yamashita, Noritoshi Saito, Mitsuhiro Kudo
  • Patent number: 4935311
    Abstract: Disclosed is a magnetic multilayered film in which layers of Fe or of an alloy containing Fe as an essential constituent are laminated together with intermediate layers of a nonmagnetic metal. In an embodiment of the magnetic multilayered film, each of the Fe layers or each of the Fe alloy layers is epitaxially grown on at least part of each of the intermediate layers of the nonmagnetic metal. A magnetic head having the magnetic multilayered film is also disclosed. The nonmagnetic metal is at least one of those selected from the group consisting of V, Cr, Cu, Nb, W, Al and Pt.
    Type: Grant
    Filed: April 13, 1988
    Date of Patent: June 19, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Ryoichi Nakatani, Toshio Kobayashi, Shigekazu Otomo, Noriyuki Kumasaka, Noritoshi Saito
  • Patent number: 4891278
    Abstract: A ferromagnetic thin film containing Fe as a main component and at least one additive element selected from the group consisting of Co, Ni, Ru, Rh, Pd, Os, Ir and Pt, in which the total content of the at least one additive element is not less than 0.1 at % and additive contents, a, b, c, d, e, f, g and h (at %) respectively of said Co, Ni, Ru, Rh, Pd, Os, Ir and Pt satisfy ##EQU1## The ferromagnetic thin film thus disclosed has a high saturation flux density of 18 KG or more, a magnetostriction constant close to zero, and excellent corrosion resistance. There is also disclosed a magnetic head using the above described ferromagnetic thin film in at least a part of a magnetic circuit thereof.
    Type: Grant
    Filed: February 19, 1987
    Date of Patent: January 2, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Shigekazu Otomo, Ryoichi Nakatani, Noriyuki Kumasaka, Noritoshi Saito, Toshio Kobayashi, Masahiko Fujishiro
  • Patent number: 4851942
    Abstract: A core burying channel is formed on the outer side surface of an air bearing rail of a floating magnetic head floating on a magnetic disk by an air-flow in a direction perpendicular to a magnetic recording medium travelling direction, and a magnetic core is buried in this core burying channel. This magnetic head can be produced easily by a production method which forms a core burying channel in a non-magnetic block, then deposits a magnetic material to the core burying channel and removes unnecessary portions of the magnetic material.
    Type: Grant
    Filed: September 14, 1987
    Date of Patent: July 25, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Niroyuki Kumasaka, Shigekazu Otomo, Takeo Yamashita, Noritoshi Saito, Yokuo Saitoh, Hiroshi Sakurai
  • Patent number: 4847715
    Abstract: A tunnel erasing-type magnetic head having a short distance between the gaps, wherein a second core half is sandwiched between the first core half and the third core half, a magnetic gap for recording and reproducing the signals is formed between the first core half and the second core half, and a magnetic gap for erasing is formed between the second core half and the third core half, so that the second core half can be utilized for both recording and reproducing the signals and erasing the signals. The second core half is obtained by forming a thin magnetic film of a high saturation flux density on the base portion composed of a nonmagnetic material that forms the magnetic gap. The first and third core halves are also obtained by forming a thin magnetic film of a high saturation flux density on the magnetic gap surfaces of the base portions to produce performance that can be used for the magnetic recording media having high coercive force. The magnetic head has a short distance between the gaps.
    Type: Grant
    Filed: December 15, 1986
    Date of Patent: July 11, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Noriyuki Kumasaka, Shigekazu Otomo, Takeo Yamashita, Noritoshi Saito
  • Patent number: 4774616
    Abstract: The present invention relates to a magnetic head, which can form guard bands on a magnetic recording medium and which is especially suitable for magnetic discs, and a fabrication process thereof. The magnetic core of the present invention includes a recording and reproduction head core (31) and an erasure head core (32) which is integrally joined in series to the head core (31) for forming guard bands. Magnetic circuits are constructed of metallic magnetic materials (34), (34'), (35) and (35') formed on non-magnetic members (33) and (33'). As a result, a recording medium having high coercive forces can be recorded while the track width is reduced and the fabrication is facilitated with a high accuracy.
    Type: Grant
    Filed: December 4, 1984
    Date of Patent: September 27, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Noriyuki Kumasaka, Hideo Fujiwara, Shigekazu Otomo, Takeo Yamashita, Noritoshi Saito, Mitsuhiro Kudo
  • Patent number: 4769729
    Abstract: A magnetic head includes ferromagnetic amorphous alloy multi-layer films each composed of an alternate lamination of ferromagnetic amorphous alloy layers and magnetic spacer layers. The thickness of each ferromagnetic amorphous alloy layer is of 1 .mu.m to 10 .mu.m. The thickness of each magnetic spacer layer is of 0.01 .mu.m to 0.2 .mu.m. The ferromagnetic amorphous alloy multi-layer films constitute at least parts of the head core.
    Type: Grant
    Filed: June 10, 1986
    Date of Patent: September 6, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Noriyuki Kumasaka, Shigekazu Otomo, Takeo Yamashita, Noritoshi Saito
  • Patent number: 4766039
    Abstract: A magnetic head comprising a magnetic film in at least a part of a magnetic circuit, at least a part of the magnetic film being formed in contact with, or being exposed to, an oxide or oxygen at least in a heating step at 150.degree. C. or higher in a process for preparing the magnetic head is disclosed. An amorphous alloy film for the magnetic film has the following composition formula to give distinguished head characteristics without any oxidation:Co.sub.a T.sub.b Zr.sub.c N.sub.dwhere T is at last one of Nb, Ta, W, Mo, V and Cr; N is at least one of Au, Pt and Ag; d.gtoreq.1, b>0, b.sub.1 +b.sub.2 +2c.gtoreq.10, a+d.gtoreq.80, -1.ltoreq.(3c-b.sub.1 -3b.sub.2 -5b.sub.3 -3b.sub.4 -4d)/(c+b.sub.1 +b.sub.2 +b.sub.3 +b.sub.4 +d).ltoreq.1, and a+b+c+d=100, where b.sub.1 is a Nb concentration, b.sub.2 is a Ta concentration, b.sub.3 is a W concentration, b.sub.4 is sum total of Mo, Cr and V concentrations and b=b.sub.1 +b.sub.2 +b.sub.3 +b.sub.4.
    Type: Grant
    Filed: June 17, 1986
    Date of Patent: August 23, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Shigekazu Otomo, Noriyuki Kumasaka, Noritoshi Saito, Takeo Yamashita, Kazuo Shiiki, Yoshihiro Hamakawa
  • Patent number: 4762755
    Abstract: A ferromagnetic material is composed of an iron alloy which contains 2 to 12% by weight of silicon and 5 to 25% by weight of at least one element selected from the group consisting of ruthenium, rhodium, palladium, iridium, platinum, gold and silver. This ferromagnetic material exhibits a high saturation flux density and good corrosion resistance. Excellent magnetic characteristics are obtained by a multilayered film which is obtained by alternatingly laminating the above ferromagnetic material and a spacer layer composed of other material. Further, a markedly increased recording density is exhibited by a magnetic head for perpendicular magnetic recording, when the end of the main pole is composed of the ferromagnetic material.
    Type: Grant
    Filed: October 29, 1984
    Date of Patent: August 9, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Kazuo Shiiki, Noriyuki Kumasaka, Yoshihiro Shiroishi, Hitoshi Nakamura, Yoshihiro Hamakawa, Noritoshi Saito, Shigeo Aoki, Kiminari Shinagawa, Mitsuhiro Kudo
  • Patent number: 4748089
    Abstract: A multilayered ferromagnetic amorphous alloy film is constituted by a plurality of main ferromagnetic material alloy films of a ferromagnetic amorphous alloy laminated one upon another with a spacer ferromagnetic material layer interposed therebetween, the spacer ferromagnetic material layer being of a ferromagnetic material different from the ferromagnetic alloy. Also disclosed is a magnetic head employing the above-described multilayered film for, at least, a portion of a core thereof. The multilayered film has excellent magnetic characteristics and is easily patterned.
    Type: Grant
    Filed: December 13, 1984
    Date of Patent: May 31, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Noriyuki Kumasaka, Kazuo Shiiki, Shigekazu Otomo, Yoshihiro Shiroishi, Takeo Yamashita, Noritoshi Saito, Kiminari Shinagawa, Mitsuhiro Kudo
  • Patent number: 4656547
    Abstract: There is provided a structure of a composite type magnetic head and its manufacturing method. The composite type magnetic head comprises: two high permeability ferrite blocks with projections having nearly edged sections formed thereon; magnetic films having a high saturation flux density deposited on the side faces of the projections, the magnetic films confronting each other via a functional gap near front ends of said projections; guard films deposited over the magnetic films comprising a non-magnetic material; and non-magnetic materials filled on the guard films up to side face of the coil. This magnetic head exhibits excellent recording and reproducing characteristics. The contour effect is negligibly small. The reaction between the magnetic film and the non-magnetic material is prevented by the guard film.
    Type: Grant
    Filed: May 9, 1984
    Date of Patent: April 7, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Noriyuki Kumasaka, Hideo Fujiwara, Shigekazu Otomo, Takeo Yamashita, Shinji Takayama, Noritoshi Saito, Mitsuhiro Kudo
  • Patent number: 4610935
    Abstract: A magnetic film structure comprises at least one magnetic film unit wherein a plurality of main magnetic films of 0.05 to 0.5 .mu.m thickness made of a magnetic alloy containing iron or cobalt as principal constituent and having a high saturation magnetic induction of 10,000 gauss or more and a magnetostriction of 10.sup.-6 or less are laminated through intermediate magnetic films made of a magnetic material such as a nickel and iron alloy or amorphous magnetic alloy different from that of the main magnetic film and being so thin that the influence of coercive force of the intermediate magnetic film does not come out. A plurality of the magnetic film units are also laminated through non-magnetic insulating films. The magnetic film structure has high saturation magnetic induction and low coercive force.
    Type: Grant
    Filed: January 16, 1984
    Date of Patent: September 9, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Noriyuki Kumasaka, Hideo Fujiwara, Noritoshi Saito, Shigekazu Otomo, Takeo Yamashita, Mitsuhiro Kudo
  • Patent number: 4559572
    Abstract: A magnetic head core and a method of fabricating same, wherein a magnetic circuit is constituted by a pair of magnetic films having a V-shaped cross section which face each other at each protrudent section through the gap material. The cross-sectional portion of the V-shaped film is exposed to the surface facing the magnetic recording medium. The protrusions of the magnetic film pair have tip planes parallel to each other and substantially perpendicular to the moving direction of the magnetic recording medium. The tip plane has a width defined by the line of intersection between the plane and the surface facing the magnetic recording medium in correspondence to the recording track width. At least one of the magnetic films has a window for winding an excitation coil. The magnetic film is formed on the non-magnetic protection member having a V-shaped protrusion.
    Type: Grant
    Filed: January 31, 1984
    Date of Patent: December 17, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Noriyuki Kumasaka, Hideo Fujiwara, Shigekazu Otomo, Takeo Yamashita, Shinji Takayama, Noritoshi Saito, Nobuo Kobayashi, Mitsuhiro Kudo