Patents by Inventor Hisayoshi Nakatsuka

Hisayoshi Nakatsuka 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: 4644518
    Abstract: An electromagnetic pickup cartridge having a pair of output terminals and a yoke with a pair of arms and a pair of generator coils respectively would on the arms where the first of the coils has a start terminal where the coil winding begins and an end terminal where the winding ends and the second of the coils also has a start terminal and an end terminal to thus provide a first pair of start terminals and a pair of end teminals where one of the pairs of terminals are connected to each other and the other of the pairs of terminals are respectively connected to the output terminals. In particular, the start terminals may be connected to each other while the end terminals are respectively connected to the output terminals or vice versa.
    Type: Grant
    Filed: August 30, 1984
    Date of Patent: February 17, 1987
    Assignee: Namiki Precision Jewel Co., Ltd.
    Inventor: Hisayoshi Nakatsuka
  • Patent number: 4637009
    Abstract: A pickup cartridge of the moving coil type including a magnetic circuit having, in series, (a) an armature with which the coil is associated, (b) a rear yoke, (c) a magnet, and (d) a front yoke. The improvement constitutes grounding magnetic circuit at a point substantially removed from the armature in the series magnetic circuit, the grounding point being at least as far removed from the armature as the surface of the front yoke. Preferably the grounding point is on the end of the front yoke farthest from the armature.
    Type: Grant
    Filed: August 30, 1984
    Date of Patent: January 13, 1987
    Assignee: Namiki Precision Jewel Co., Ltd.
    Inventor: Hisayoshi Nakatsuka
  • Patent number: 4388486
    Abstract: A shielded line comprising a central wire; a shielding conductor disposed around the central wire; and the central wire and shielding conductor being divided into first, second and third parts where (a) the central wires of the first and third parts are connected to the shielding conductor of the second part and (b) the central wire of the second part is connected to the shielding conductors of the first and third parts so that a signal applied to the central wire of the first part flows through the central wire of the first part, the shielding conductor of the second part and the central wire of the third part and a signal applied to the shielding conductor of the first part flows through the shielding conductor of the first part, the central wire of the second part and the shielding conductor of the third part.
    Type: Grant
    Filed: April 7, 1981
    Date of Patent: June 14, 1983
    Assignee: Namiki Precision Jewel Co., Ltd.
    Inventor: Hisayoshi Nakatsuka
  • Patent number: 4220341
    Abstract: A phonograph pickup comprises the end portion of a cylindrical pole leg and an opposing yoke with an air gap therebetween, and a moving system including a stylus arm and an armature. A pivoting means provides for pivotal mounting of the moving system in the air gap, and comprises a first resilient bearing spaced a first distance from the pivot point for supporting the armature, and a second resilient bearing spaced a second distance (greater than the first distance) from the pivot point for engaging the moving system with a lower pressure than the first resilient bearing.
    Type: Grant
    Filed: February 2, 1979
    Date of Patent: September 2, 1980
    Assignee: Ortofon Manufacturing A/S
    Inventor: Hisayoshi Nakatsuka
  • Patent number: 4183537
    Abstract: A pick up lateral pressure detector detachably mountable on the tone arm of a photograph record player, the detector comprising a base detachably mountable with respect to the tone arm, a pivotal member so mounted with respect to the base that the axis of rotation thereof is substantially perpendicular to the surface of the phonograph record, a cantilever so mounted with respect to the pivotal member that it can oscillate with respect to the pivotal member at least in a direction substantially parallel to the phonograph record surface, a reproduction needle mounted on the cantilever adapted to engage the groove of the phonograph record, and indicating means responsive to the rotation of the pivotal member and the cantilever about the axis of rotation of the pivotal member for indicating the lateral pressure of the record groove on the reproduction needle.
    Type: Grant
    Filed: December 12, 1977
    Date of Patent: January 15, 1980
    Assignee: Namiki Precision Jewel Co., Ltd.
    Inventor: Hisayoshi Nakatsuka
  • Patent number: 4162076
    Abstract: A tone arm for use in a phonograph record player having a base, the tone arm comprising tone arm shaft having pick up means disposed at one end thereof and a balance weight disposed at the other end thereof, the tone arm shaft having a longitudinal axis extending between the ends thereof, a tone arm shaft holder for pivotally mounting the tone arm shaft with respect to the phonograph record player base about a vertical axis, balance weight mounting means for pivotally mounting the balance weight with respect to the tone arm shaft about a balance weight axis different from the vertical axis about which the tone arm shaft pivots.
    Type: Grant
    Filed: December 12, 1977
    Date of Patent: July 24, 1979
    Assignee: Namiki Precision Jewel Co., Ltd.
    Inventor: Hisayoshi Nakatsuka
  • Patent number: 4147364
    Abstract: A tone arm adapted to be disposed between a head shell and a holder for the tone arm, the tone arm comprising at least one hollow member contacting the head shell or the tone arm support and having an orientation axis extending through the hollow portion of the hollow member where the angle .theta. between the orientation axis and an arm shaft axis extending between the head shell and the tone arm holder is greater than 0.degree. whereby a mechanical vibration introduced into the tone arm from a vibration source comprising either the head shell or the tone arm holder is divided between two paths both of which start at the contact point between the hollow member and the vibration source and then pass around the respective sides of the hollow member to a cancellation point where the vibrations in the two paths substantially cancel one another due to difference in their direction of travel.
    Type: Grant
    Filed: December 12, 1977
    Date of Patent: April 3, 1979
    Assignee: Namiki Precision Jewel Co., Ltd.
    Inventor: Hisayoshi Nakatsuka
  • Patent number: 4145582
    Abstract: A moving coil pickup of the type having a substantially square magnetic armature mounted in an air gap defined between two opposed pole faces of magnetic members in a magnetic circuit wherein the shape of the pole faces is conformed to the shape of the armature by making at least one end portion of at least one of the magnetic members substantially square in cross-section.
    Type: Grant
    Filed: April 12, 1976
    Date of Patent: March 20, 1979
    Assignee: Ortofon Manufacturing A/S
    Inventor: Hisayoshi Nakatsuka
  • Patent number: 4138122
    Abstract: A phonograph pickup having an armature supported by a resilient pad which restores the armature to a neutral position after excursions thereof. A further resilient means is provided, which engages the armature at a greater distance from its fulcrum than does the pad. The additional resilient means is made of a material having good damping characteristics.
    Type: Grant
    Filed: June 20, 1977
    Date of Patent: February 6, 1979
    Assignee: Ortofon Manufacturing A/S
    Inventor: Hisayoshi Nakatsuka