Patents Assigned to Sumida Electric Co., Ltd.
  • Patent number: 7515443
    Abstract: An inverter circuit is configured with a reduced number of components for driving a plurality of discharge tubes. Primary coils of a plurality of drive transformers are respectively connected in series to primary coils of corresponding balancer-transformers, and then connected between output terminals of a switching circuit in parallel. The secondary coils of the balancer-transformers are connected in series, and connected between the output terminals of the switching circuit to configure an inverter circuit for driving a plurality of discharge tubes. The inverter circuit includes a voltage detecting circuit for detecting a voltage at any of connecting-midpoint of the series-connected secondary coils of the balancer-transformers, and a voltage comparing circuit for comparing an output of the voltage detecting circuit with a reference voltage. A signal designates an abnormal operation at an output of the voltage comparing circuit when the voltage of the connecting-midpoint exceeds the reference voltage.
    Type: Grant
    Filed: June 12, 2007
    Date of Patent: April 7, 2009
    Assignee: Sumida Electric Co., Ltd.
    Inventors: Hiroyuki Miyazaki, Takeshi Hatakeyama
  • Patent number: 7397336
    Abstract: Disclosed is a coil component having a magnetic core that is made of a magnetic material, and a terminal electrode portion and a coil portion that are made of a conductive material, wherein the coil components is configured such that the magnetic material and the conductive material contact with each other, and there is a relation of RM?20ZO when an insulation resistance of the magnetic core is RM (?) and a peak impedance of the coil component is ZO (?).
    Type: Grant
    Filed: November 6, 2006
    Date of Patent: July 8, 2008
    Assignee: Sumida Electric Co., Ltd.
    Inventor: Mitsugu Kawarai
  • Publication number: 20080025055
    Abstract: An inverter circuit is configured with a reduced number of components for driving a plurality of discharge tubes. Primary coils of a plurality of drive transformers are respectively connected in series to primary coils of corresponding balancer-transformers, and then connected between output terminals of a switching circuit in parallel. The secondary coils of the balancer-transformers are connected in series, and connected between the output terminals of the switching circuit to configure an inverter circuit for driving a plurality of discharge tubes. The inverter circuit includes a voltage detecting circuit for detecting a voltage at any of connecting-midpoint of the series-connected secondary coils of the balancer-transformers, and a voltage comparing circuit for comparing an output of the voltage detecting circuit with a reference voltage. A signal designates an abnormal operation at an output of the voltage comparing circuit when the voltage of the connecting-midpoint exceeds the reference voltage.
    Type: Application
    Filed: June 12, 2007
    Publication date: January 31, 2008
    Applicant: SUMIDA ELECTRIC CO., LTD.
    Inventors: Hiroyuki Miyazaki, Takeshi Hatakeyama
  • Publication number: 20070296535
    Abstract: An inverter transformer to which coils for a balance transformer are integrally assembled. The inverter transformer is employed in a drive circuit for evenly driving a plurality of discharge tubes, and includes a primary coil and a secondary coil. The present invention proposes the inverter transformer which performs reduction in the number of components and in the size thereof by providing a through-hole a portion of a magnetic core section made from magnetic material configuring the inverter transformer, and by providing coils for a balance transformer through the through-hole.
    Type: Application
    Filed: June 12, 2007
    Publication date: December 27, 2007
    Applicant: SUMIDA ELECTRIC CO., LTD.
    Inventor: Tadayuki Fushimi
  • Patent number: 7259650
    Abstract: A magnetic element including coils; a first core and a second core each of which has a planar plate portion, outer leg portions and a middle leg portion which is inserted into aforesaid coil; and an intermediate core to form a closed magnetic circuit which is disposed between the aforesaid first core and the aforesaid second core in a manner connecting integrally with the aforesaid first core and aforesaid second core. In addition, the magnetic element is made into a configuration that has relations of S1?S3 and also S1?S2 when a cross-sectional area of the middle leg portion of the aforesaid first core is S1, a cross-sectional area of the aforesaid intermediate core is S2 and a cross-sectional area of the middle leg portion of the aforesaid second core is S3.
    Type: Grant
    Filed: June 27, 2006
    Date of Patent: August 21, 2007
    Assignee: Sumida Electric Co., Ltd.
    Inventor: Kan Sano
  • Patent number: 7042324
    Abstract: A surface mount inductor has a drum core, a winding to be wound around a winding shaft section of the drum core, a case body of a nonconductive material to be disposed to surround the winding, a binding terminal fixed to the case body and protruding radially outward from the case body to be bound a winding terminal to, and a metal terminal member having a planar terminal to be a contact portion with a substrate when the surface mount inductor is surface mounted on the substrate. The inductor includes an extended portion protruding radially outward from the case body and having a wider width than or approximately the same width as of the binding terminal, the extended portion being disposed at a overlapping position with the binding terminal in a height direction of the drum core. The winding terminal is wound around from the outer peripheral side of both the binding terminal and the extended portion.
    Type: Grant
    Filed: June 22, 2004
    Date of Patent: May 9, 2006
    Assignees: Sumida Corporation, Sumida Electric Co., Ltd.
    Inventor: Yoshito Watanabe
  • Patent number: 6950002
    Abstract: An inductance element having a drum core around which a winding is to be wound and a ring core surrounding a circumference of the drum core, in which projections are provided either on an outer side surface of an upper flange section of the drum core or an inner side surface of the ring core, and recessions are provided in the other side surface to fit with the projections, each of the recession having an inclined plane inclining from the deepest part of the recession toward the outer edge on one side of the recession and having a bilaterally asymmetric cross-sectional shape with respect to a perpendicular line drawn from the deepest part to an opening of the recession viewing from the direction of an upper surface of the ring core.
    Type: Grant
    Filed: November 12, 2004
    Date of Patent: September 27, 2005
    Assignees: Sumida Corporation, Sumida Electric Co., Ltd.
    Inventor: Kan Sano
  • Patent number: D434723
    Type: Grant
    Filed: June 4, 1999
    Date of Patent: December 5, 2000
    Assignee: Sumida Electric Co., Ltd.
    Inventor: Tadayuki Fushimi