Patents by Inventor Masashi Norizuki

Masashi Norizuki 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: 7280022
    Abstract: An inverter transformer in which to overall structure and manufacturing process can be simplified despite its closed magnetic path structure, and a cost increase can be suppressed. Primary windings (24a, 24b, 24c) and secondary windings (25a, 25b, 25c) wound around a plurality of rod-like cores (23a, 23b, 23c) have leakage inductances. The primary windings (24a, 24b, 24c) axe wound around respective rod-like cores (23a, 23b, 23c) such that magnetic fluxes being induced in respective cores by the currents flowing through the primary windings (24a, 24b, 24c) are directed reversely to magnetic fluxes being induced in adjacent cores.
    Type: Grant
    Filed: June 3, 2004
    Date of Patent: October 9, 2007
    Assignee: Minebea Co., Ltd.
    Inventors: Hiroshi Shinmen, Masashi Norizuki
  • Publication number: 20060279392
    Abstract: In an inverter transformer, a primary winding and a secondary winding are wound around each of a plurality of bar-shaped magnetic cores so that the primary and the secondary windings have respective predetermined leakage inductances. The primary windings are wound in such a manner that a magnetic flux generated in one magnetic core by a current flowing through a primary winding provided around the one magnetic core is directed opposite to a magnetic flux generated in another magnetic core adjacent to the one magnetic core by a current flowing through a primary winding provided around the adjacent magnetic core.
    Type: Application
    Filed: June 3, 2004
    Publication date: December 14, 2006
    Applicant: Minebea Co., Ltd.
    Inventors: Hiroshi Shinmen, Masashi Norizuki
  • Patent number: 7108799
    Abstract: An electromagnetic wave absorber is formed of an Mn—Zn ferrite including: a spinel primary phase which contains 40.0 to 49.9 mol % Fe2O3, 4.0 to 26.5 mol % ZnO, and the remainder consisting of MnO; and a secondary phase which contains CaO as a base component. In the ferrite, the spinel primary phase accounts for 50.0 to 99.0% of the aggregate mass of the spinel primary phase and the secondary phase.
    Type: Grant
    Filed: January 30, 2004
    Date of Patent: September 19, 2006
    Assignee: Minebea Co., Ltd.
    Inventors: Osamu Kobayashi, Kiyoshi Ito, Masashi Norizuki
  • Patent number: 7101488
    Abstract: An electromagnetic wave absorber is formed of an Mn—Zn ferrite including: a spinel primary phase which contains 40.0 to 49.9 mol % Fe2O3, 4.0 to 26.5 mol % ZnO, 0.1 to 4.0 mol % TiO2 and/or SnO2, and the remainder consisting of MnO; and a secondary phase which contains CaO as a base component. In the ferrite, the mass of the spinel primary phase accounts for 50.0 to 99.0% of the aggregate mass of the spinel primary phase and the secondary phase.
    Type: Grant
    Filed: January 30, 2004
    Date of Patent: September 5, 2006
    Assignee: Minebea Co., Ltd.
    Inventors: Osamu Kobayashi, Kiyoshi Ito, Masashi Norizuki
  • Publication number: 20060132273
    Abstract: In an inverter transformer, a primary winding and a secondary winding are wound around each of two bar-shaped magnetic cores, and a magnetic resin covers all or some portions, including at least both end portion of the circumference, of the bar-shaped magnetic cores so that the primary and the secondary windings have respective predetermined leakage inductances. The magnetic resin has a substantially smaller relative magnetic permeability than the bar-shaped magnetic cores. Part of magnetic flux generated at the bar-shaped magnetic cores leaks out beyond the bar-shaped magnetic cores and further beyond the magnetic resin so as to provide leakage inductance, which functions as ballast inductance. Also, the amount of magnetic flux passing through the magnetic resin and leaking out beyond the magnetic resin is reduced, and influence to the area around the inverter transformer is reduced.
    Type: Application
    Filed: June 3, 2004
    Publication date: June 22, 2006
    Inventors: Hiroshi Shinmen, Masashi Norizuki
  • Publication number: 20040185289
    Abstract: An electromagnetic wave absorber is formed of an Mn—Zn ferrite including: a spinel primary phase which contains 40.0 to 49.9 mol % Fe2O3, 4.0 to 26.5 mol % ZnO, and the remainder consisting of MnO; and a secondary phase which contains CaO as a base component. In the ferrite, the spinel primary phase accounts for 50.0 to 99.0% of the aggregate mass of the spinel primary phase and the secondary phase.
    Type: Application
    Filed: January 30, 2004
    Publication date: September 23, 2004
    Applicant: MINEBA CO., LTD.
    Inventors: Osamu Kobayashi, Kiyoshi Ito, Masashi Norizuki
  • Publication number: 20040183711
    Abstract: An electromagnetic wave absorber is formed of an Mn—Zn ferrite including: a spinel primary phase which contains 40.0 to 49.9 mol % Fe2O3, 4.0 to 26.5 mol % ZnO, 0.1 to 4.0 mol % TiO2 and/or SnO2, and the remainder consisting of MnO; and a secondary phase which contains CaO as a base component. In the ferrite, the mass of the spinel primary phase accounts for 50.0 to 99.0% of the aggregate mass of the spinel primary phase and the secondary phase.
    Type: Application
    Filed: January 30, 2004
    Publication date: September 23, 2004
    Applicant: MINEBEA CO., LTD.
    Inventors: Osamu Kobayashi, Kiyoshi Ito, Masashi Norizuki
  • Patent number: 6069458
    Abstract: This invention is to provide an inexpensive high intensity discharge lamp lighting device having a simplified circuit construction, which does not use a full-bridge mode inverter. The high intensity discharge lamp lighting device includes a rectifier for a power-frequency power supply, a booster chopper mode sine wave converter, a zero volt switching push pull inverter, and a high intensity lamp of a halide lamp. And, as a starting device for the halide lamp, the high intensity discharge lamp lighting device generates a high voltage (5 KV) using a resonance by a ballast choke for the inverter and a condenser connected in parallel to the halide lamp, thereby inducing a glow discharge. And, a PFM (pulse frequency modulation) circuit controls the lamp current of the halide lamp to keep it constant.
    Type: Grant
    Filed: September 18, 1996
    Date of Patent: May 30, 2000
    Assignee: Minebea Co., Ltd.
    Inventors: Takao Takehara, Masashi Norizuki
  • Patent number: 5798616
    Abstract: A fluorescent lamp circuit having a power-factor improving step-up chopper and an inverter to covert an output of the step-up chopper and to drive the fluorescent lamp. A switching circuit of the step-up chopper and a switching circuit of the inverter are operated by a switching element consisting of a single transistor.
    Type: Grant
    Filed: April 1, 1996
    Date of Patent: August 25, 1998
    Assignee: Minebea Co., Ltd.
    Inventors: Takao Takehara, Masashi Norizuki
  • Patent number: 5640313
    Abstract: The present invention is disclosed to provide an inverter allowing a remarkable reduction in the number of parts used for an inverter unit which can improves the efficiency and allows current control in a wide range.Namely, the inverter unit for converting a direct current supplied from DC power supply, into an alternating current by conversion means alternatively converting the flowing direction of direct current by SWITCH ON/SWITCH OFF operation of a switching element, comprises a series resonance circuit formed at the primary side of a step-up transformer, a control means for switching ON/OFF said series resonance circuit by the switching element at a timing led in phase from the resonant frequency of this resonance circuit, and a load connected at the secondary side of the transformer, so as to solve the problems described above.
    Type: Grant
    Filed: March 27, 1996
    Date of Patent: June 17, 1997
    Assignee: Minebea Co., Ltd.
    Inventors: Takao Takehara, Masashi Norizuki, Atsuyoshi Tamagawa