Patents by Inventor Kunihiko Azuma

Kunihiko Azuma 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).

  • Publication number: 20090267679
    Abstract: To provide an analog multiplexer capable of extending the frequency characteristic of the analog multiplexer in terms of frequency band.
    Type: Application
    Filed: March 20, 2009
    Publication date: October 29, 2009
    Inventor: Kunihiko Azuma
  • Patent number: 5831680
    Abstract: In a color signal processing circuit capable of processing a PAL/NTSC color television signal, in order to prevent an image deterioration caused by chromatization when a PAL signal is received in an NTSC signal receiving mode, there is provided a gate control signal generating circuit for alternately generating gate control signals "GA" and "GK", one for one horizontal period and the other for a next one horizontal period, in response to application of a phase inverting pulse "R" which inverts in polarity every one horizontal period.
    Type: Grant
    Filed: March 15, 1996
    Date of Patent: November 3, 1998
    Assignee: NEC Corporation
    Inventors: Kunihiko Azuma, Kenji Mori
  • Patent number: 5528124
    Abstract: A phase control circuit for operating a phase shift in accordance with a control voltage comprises four differential circuits, two of which form a multiplier circuit for providing a basic function for a phase shift operation of the phase control circuit, and the rest of which cancel variations in amplitude generated during the phase shift operation. The amplitude compensation is accomplished by a construction in which a ratio of an emitter area of a first bipolar transistor in each of the differential circuits to an emitter area of the second bipolar transistor in each of the differential circuits is set at a value between 2 and 3. Alternatively, the amplitude compensation is provided by a level shift circuit providing an offset voltage in the control voltage supplied to two of the differential circuits.
    Type: Grant
    Filed: March 22, 1995
    Date of Patent: June 18, 1996
    Assignee: NEC Corporation
    Inventor: Kunihiko Azuma
  • Patent number: 5485128
    Abstract: An oscillator circuit including a current-controlled phase shift circuit and a feedback circuit including a quartz resonator is capable of varying the oscillation frequency in accordance with control current signals. A phase shift circuit included in the current-controlled phase shift circuit includes a first low-pass filter including a resistor and a capacitor, a first buffer amplifier, a second low-pass filter including a resistor and a capacitor, and a second buffer amplifier. The phase shift circuit has a significant gain at any frequency for oscillation. Especially an oscillation circuit implemented by an integrated circuit satisfies the suitable condition in which relative value of resistances and capacitances do not vary.
    Type: Grant
    Filed: December 6, 1994
    Date of Patent: January 16, 1996
    Assignee: NEC Corporation
    Inventor: Kunihiko Azuma
  • Patent number: 5434718
    Abstract: An automatic gain controlling circuit is associated with magnetic heads for recording and reproducing pieces of video data information on a magnetic tape, and an in-phase current component is eliminated from a recording current flowing into one of the magnetic heads through a differential amplification between two input voltage levels produced from the recording current with the in-phase current component so that a gain control voltage signal is free from a relative accuracy between circuit components causative of the in-phase current component.
    Type: Grant
    Filed: June 2, 1994
    Date of Patent: July 18, 1995
    Assignee: NEC Corporation
    Inventor: Kunihiko Azuma
  • Patent number: 5094331
    Abstract: A wet-type multiplate clutch for selectively transmitting drive forces from an engine to a road wheel has a plurality of clutch discs adapted to be coupled to the engine and each having a frictional surface, and a plurality of clutch plates adapted to be coupled to the road wheel, of clutch discs and the clutch plates being alternately interleaved and arranged so that the clutch discs and the clutch plates can be pressed against and separated from each other. Each of the clutch discs having a ring-shaped frictional member or a plurality of frictional members on the frictional surface, and radial oil passages for allowing oil to pass therethrough and oil grooves for retaining oil therein.
    Type: Grant
    Filed: October 31, 1990
    Date of Patent: March 10, 1992
    Assignees: Honda Giken Kogyo Kabushiki Kaisha, Kabushiki Kaisha F.C.C.
    Inventors: Katsumi Fujimoto, Hisanori Esaki, Kunihiko Azuma, Yusuke Oishi, Yasutada Suzuki
  • Patent number: 4830163
    Abstract: A centrifugal clutch comprises a driving plate having oppositely facing surfaces secured to an input shaft operatively connected to a driving source, a cylindrical bottomed drum detachably secured to an end, projecting from the input shaft, of an output shaft concentrically and relatively rotatably disposed within the input shaft, the cylindrical bottomed drum surrounding the driving plate, and a plurality of clutch springs each connected to each of a plurality of shoes which are supported on the plate for movement toward and away from an inner peripheral surface of the drum respectively by a plurality of stub shafts parallel to the input shaft, the clutch spring providing a spring force in a direction away from the inner peripheral surface of the drum.
    Type: Grant
    Filed: July 21, 1987
    Date of Patent: May 16, 1989
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Kunio Miyazaki, Kunihiko Azuma, Satoru Noguchi