Patents by Inventor Noboru Yamanaka

Noboru Yamanaka 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: 6198600
    Abstract: The present invention is directed to a thin film magnetic head and its manufacturing method. A slider 1 is provided with base body surfaces 13 and 14 at its surface facing opposite a medium. An inductive thin film magnetic transducer 2 is provided with a first pole tip P1 and a second pole tip P2 whose front ends emerge at the base body surfaces 13 and 14 and indented portions 4 and 5 provided at the base body surfaces 13 and 14. A protective film 10 covers the base body surfaces 13 and 14 and indented portions 4 and 5. The thickness of the protective film 10 at the indented portions 4 and 5 is larger than the thickness at the base body surfaces 13 and 14. The magnetic films constituting the pole tips P1 and P2 can thus be reliably protected from oxidation, corrosion and the like, while minimizing the spacing loss.
    Type: Grant
    Filed: June 8, 1999
    Date of Patent: March 6, 2001
    Assignee: TDK Corporation
    Inventors: Mitsuhiro Kitao, Hiroki Nakazawa, Keiichi Shibata, Monjiro Momoi, Noboru Yamanaka
  • Patent number: 6144533
    Abstract: The present invention relates to a thin film magnetic head that achieves low NLTS and demonstrates outstanding O/W characteristics in a high frequency range. A first magnetic film and a second magnetic film face opposite each other over a gap film at a side where a surface facing opposite the medium is present. A first yoke and a second yoke, which extend rearward on the opposite side from the surface facing opposite the medium, are linked to each other at a rear linking portion. A coil film, which is supported by an insulating film, is provided in a coil around the rear linking portion. N/YL.gtoreq.0.2 (turns/.mu.m) is satisfied, with YL (.mu.m) representing the distance from the surface facing opposite the medium to the rear linking portion and N (turns) representing the number of turns of the coil film.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: November 7, 2000
    Assignee: TDK Corporation
    Inventors: Kazumasa Fukuda, Noboru Yamanaka, Yuzuru Iwai
  • Patent number: 6075676
    Abstract: A head assembly including a suspension, a head slider mounted on a front end portion of the suspension and having a magnetoresistive element, and a pair of lead lines formed on the suspension and having first ends connected to the magnetoresistive element. The head assembly further includes a metal ball connected by bonding to the pair of lead lines. In handling the head assembly as a separate member, a current caused by static electricity flows through the metal ball short-circuiting the pair of lead lines, thereby preventing burning of the magnetoresistive element due to the current. After mounting the head assembly to an actuator arm, the metal ball is removed to electrically open the pair of lead lines.
    Type: Grant
    Filed: September 14, 1998
    Date of Patent: June 13, 2000
    Assignees: Fujitsu Limited, TDK Corp.
    Inventors: Shinji Hiraoka, Masashi Shiraishi, Takuro Tsuruda, Noboru Yamanaka
  • Patent number: 6031696
    Abstract: A thin-film magnetic head includes a recording gap layer, lower and upper magnetic pole layers deposited to sandwich the recording gap layer, the upper magnetic pole layer having side surfaces facing toward a track width direction, and non-magnetic conductive material members being in contact with at least a part of the respective side surfaces of the upper magnetic pole layer and in contact with the lower magnetic pole layer.
    Type: Grant
    Filed: June 8, 1998
    Date of Patent: February 29, 2000
    Assignee: TDK Corporation
    Inventor: Noboru Yamanaka
  • Patent number: 5995329
    Abstract: A hard magnetic disc unit having a plurality of head gimbal assemblies. Each head gimbal assembly has a magnetic head slider, a metal suspension for supporting the magnetic head slider, and insulating material layer formed on the metal suspension, and a conductive pattern of lead lines electrically connected with the magnetic head. The conductive pattern is formed on the insulating material layer. There are arm portions for supporting the respective head gimbal assemblies and an actuator for moving the arm portions to position the magnetic head sliders. There are also a plurality of resistors having a high resistance value for discharging electrostatic charge. The head gimbal assemblies are electrically insulated from a ground, and the resistors are connected between the head gimbal assemblies and the ground, respectively.
    Type: Grant
    Filed: May 1, 1998
    Date of Patent: November 30, 1999
    Assignee: TDK Corporation
    Inventors: Masashi Shiraishi, Noboru Yamanaka
  • Patent number: 5978176
    Abstract: The present invention is directed to provide a magnetic head that is capable of effectively preventing TA noise.A slider 1 is provided with air bearing surfaces 111 and 121. Electromagnetic conversion elements 2 and 3, which are provided toward the trailing edge TR of the slider 1, perform electromagnetic conversion at the air bearing surfaces 111 and 121. The slider 1 is provided with indented portions 114 and projecting portions 115 at the air bearing surfaces 111 and 121 where the electromagnetic conversion elements 2 and 3 are provided. The indented portions 114 are provided in the areas corresponding to the width W2 of the electromagnetic conversion elements 2 and 3 viewed in the direction of the track width further toward the trailing edge TR than the electromagnetic conversion elements 2 and 3. The projecting portions 115 are provided adjacent to the indented portions 114 further projecting out compared to the indented portions 114.
    Type: Grant
    Filed: October 20, 1997
    Date of Patent: November 2, 1999
    Assignee: TDK Corporation
    Inventors: Joichiro Ezaki, Noboru Yamanaka, Izumi Nomura
  • Patent number: 5768053
    Abstract: A flying magnetic head slider with leading and trailing edges and side edges includes a plurality of rails extending along the side edges from the leading edge to the trailing edge. At least one of the rails includes a first narrow portion with a narrower rail width, located at a position near the leading edge, at least one second narrow portion with a partially narrower rail width, located at a position apart from the leading edge by a distance with a ratio of 0.6 to 0.9 to a whole longitudinal length of the slider, and a widening portion located between the at least one second narrow portion and the trailing edge, partially having a rail width increasing from the narrower rail width of the second narrow portion.
    Type: Grant
    Filed: July 24, 1996
    Date of Patent: June 16, 1998
    Assignee: TDK Corporation
    Inventors: Noboru Yamanaka, Masashi Shiraishi
  • Patent number: 5718035
    Abstract: A method for manufacturing a thin film magnetic head includes a step of preparing a wafer with a thickness greater than a desired slider length for the magnetic head, a step of forming a plurality of thin film magnetic head elements on one surface of the wafer, a step of slicing the wafer to obtain a plurality of bars so that each of the bars includes a plurality of the thin film magnetic head elements, and a step of longitudinally cutting each of the bars in parallel with a first side face of the bar, on which the thin film magnetic head elements are formed, to remove a portion of the bar at the side of a second side face which is opposed to the first side face so that a length of the bar becomes equal to the desired slider length for the magnetic head.
    Type: Grant
    Filed: February 6, 1996
    Date of Patent: February 17, 1998
    Assignee: TDK Corporation
    Inventors: Noboru Yamanaka, Shunichi Katase
  • Patent number: 5236735
    Abstract: A method of producing a thin film magnetic head comprises forming a thin film magnetic circuit including a magnetic film and a conductive coil film on a substrate, and heating the thin film magnetic circuit at a temperature in a range of from 270.degree. C. to 400.degree. C. before forming a protective layer covering the thin film magnetic circuit.
    Type: Grant
    Filed: June 13, 1991
    Date of Patent: August 17, 1993
    Assignee: TDK Corporation
    Inventors: Makoto Yoshida, Yuzuru Iwai, Noboru Yamanaka, Jun Shouzi, Tsutomu Koyanagi, Mikio Matsuzaki, Nobuya Ohyama, Yoshiaki Tanaka