Patents Assigned to KOA Corporation
  • Publication number: 20150323567
    Abstract: Provided is a metal plate resistor, which is able to be manufactured easily, and which has heat dissipation characteristics with a small variation, while maintaining small and compact structure. The resistor includes a resistance body (11) consisting of a metal material, a terminal portion (12) electrically conducting to the resistance body, a mold body (20) for covering the resistance body, a guide member (16A) formed on a portion on a surface of the resistance body except a central portion thereof, and a heat equalizing plate (14) disposed on the guide member and adhered at least to a central portion of the resistance body by an adhesive for absorbing heat generated in the resistance body. The guide member (16A) is preferably formed by pre-molding and disposed on a mount surface side of the resistance body. The heat equalizing plate (14) preferably overwraps on the terminal portions (12).
    Type: Application
    Filed: May 1, 2015
    Publication date: November 12, 2015
    Applicant: KOA CORPORATION
    Inventors: Hiromitsu Kitahara, Takayuki Yamabe
  • Publication number: 20150226768
    Abstract: Provided is a resistor for detecting current, which includes a voltage terminal member capable of removing an influence of error voltage, formed by tiny amount of self inductance existing in the resistor. The voltage terminal member includes a resistance body (11); a pair of electrodes (12) fixed to each end of the resistance body; and a pair of voltage terminal members (3) for detecting voltage generated in the resistance body and that are connected to each electrode; wherein the voltage terminal member (3) includes a connecting portion (3b) for connecting to the electrode (12), an extending portion (3c1,3c2) extending from the connecting portion toward the other electrode side; and wherein each end of the extending portion reaches to same plane (X) perpendicular to current path between the electrodes.
    Type: Application
    Filed: August 21, 2013
    Publication date: August 13, 2015
    Applicant: KOA CORPORATION
    Inventors: Keishi Nakamura, Koichi Hirasawa
  • Publication number: 20150212115
    Abstract: Provided is a current detection resistor that is small and that inhibits influence of the skin effect due to high frequency current. The resistor includes a resistor body (11) and at least a pair of electrodes (12), wherein the resistor body (11) is configured in a pillar-shape having diameter of 4 mm or less disposed between the electrodes. Each of the electrodes (12) is made to be longer in the direction in which the electrodes are placed and longer than twice the distance between the electrodes, which sandwich the resistor body. Further, each of electrodes (12) is square pillar-shaped, and the resistor body is fixed to roughly to center of the electrode in cross-section.
    Type: Application
    Filed: August 21, 2013
    Publication date: July 30, 2015
    Applicant: KOA CORPORATION
    Inventors: Keishi Nakamura, Koichi Hirasawa, Kenji Kameko
  • Publication number: 20140370754
    Abstract: Provided is a connection structure for a detection terminal of shunt resistor that allows a lead wire, that is to be connected to an electrode of the shunt resistor and is for detecting electrical current, to be easily and compactly connected to the electrode within a narrow and small module. A terminal connection structure for a resistor, which connects a detection terminal to an electrode, comprises a shunt resistor (13) that has a pair of electrodes (12) at both ends of a resistor body (11); a connector base (14) formed of insulating material; and an electrically conductive section (15a) formed on the connector base (14); wherein the connector base (14) is fit onto the shunt resistor (13) such that the electrically conductive section (15a) is electrically connected to the electrodes (12). The connector base (14) is provided with a joint section (C) that can be fit onto the resistor body (11).
    Type: Application
    Filed: January 29, 2013
    Publication date: December 18, 2014
    Applicant: KOA CORPORATION
    Inventors: Kenji Kameko, Koichi Hirasawa, Yoshinori Aruga
  • Patent number: 8912876
    Abstract: A surface mounting varistor for high voltages and current pulses without any risk of burning a mounting board is provided. A covering material for a varistor 1 has a duplex (two layer) structure made from a first mold layer 13 and a second mold layer 15, and a leg with a predetermined height is formed on the bottom of the covering material. As a result, a space (void) formed between a varistor element 2 and a mounting board 20 when the varistor 1 is mounted on the board 20 allows avoidance of the risk of burning the board 20, even if the varistor short-circuits.
    Type: Grant
    Filed: June 17, 2011
    Date of Patent: December 16, 2014
    Assignee: KOA Corporation
    Inventors: Yoji Gomi, Tatsuya Kanzaki
  • Patent number: 8895869
    Abstract: Electrode protective films 13a and 13b are formed on the surface of the metal layer using imidazole preflux, as terminal electrodes 35a and 35b of an electronic component. The terminal electrodes of an electronic component on which the protective films are formed are fixed by electroconductive adhesives 33a and 33b supplied to mounting lands 40a and 40b. Thereby an electronic component mounting structure without change in resistance caused by electroconductive adhesives is provided.
    Type: Grant
    Filed: November 9, 2010
    Date of Patent: November 25, 2014
    Assignee: Koa Corporation
    Inventor: Toshifumi Mizokami
  • Publication number: 20140125429
    Abstract: Provided is a voltage detection circuit, which can remove influence of error voltage caused by tiny amount of self-inductance existing in a shunt resistor, though in the resistor for large current usage, which is impossible to surface-mount on a voltage detection circuit board. The shunt resistor device comprises: a resistance body (11); a pair of main electrode (12) for flowing current to be monitored through the resistance body; a pair of detection terminal (13a) for detecting voltage caused in the resistance body; and a pair of wiring (23) each electrically connected to the detection terminal. And, a pair of voltage detection wiring consisting of the detection terminal (13a) and the wiring (23) is brought closer, at prescribed location, than distance between each of connection position of the pair of the detection terminal (13a) on the main electrode (12).
    Type: Application
    Filed: July 20, 2012
    Publication date: May 8, 2014
    Applicant: KOA CORPORATION
    Inventors: Tadahiko Yoshioka, Koichi Hirasawa, Yoshinori Aruga
  • Publication number: 20140097933
    Abstract: Provided is a shunt resistor, which controls an influence of skin effect by high frequency current. The shunt resistor has a rod-shaped resistance body (11), and a pair of main electrode (12), of another material from the resistance body, wherein end faces of the resistance body and the main electrode are bonded. The resistance body (11) has a hole (11a) going through in direction where main electrodes are disposed, or a high resistance part (11b) going through at its axis portion that is highly resistive than outer part, and low resistance part (11c) that is formed in outer of the high resistance part. It is preferable that outer circumference of the resistance body is circle-shaped. Since, current doesn't flow fundamentally in the through hole or the high resistance part, fluctuation band in the current pathway can be reduced. Therefore, change of resistance value by skin effect by high-frequency current can be reduced.
    Type: Application
    Filed: December 11, 2013
    Publication date: April 10, 2014
    Applicant: KOA CORPORATION
    Inventors: Tadahiko Yoshioka, Koichi Hirasawa, Yoshinori Aruga
  • Publication number: 20130162388
    Abstract: A surface mounting varistor for high voltages and current pulses without any risk of burning a mounting board is provided. A covering material for a varistor 1 has a duplex (two layer) structure made from a first mold layer 13 and a second mold layer 15, and a leg with a predetermined height is formed on the bottom of the covering material. As a result, a space (void) formed between a varistor element 2 and a mounting board 20 when the varistor 1 is mounted on the board 20 allows avoidance of the risk of burning the board 20, even if the varistor short-circuits.
    Type: Application
    Filed: June 17, 2011
    Publication date: June 27, 2013
    Applicant: KOA Corporation
    Inventors: Yoji Gomi, Tatsuya Kanzaki
  • Patent number: 8471674
    Abstract: Provided is a shunt resistor which has an excellent accuracy of current detection and a small temperature drift as well as a compact structure, and improves the operability. The shunt resistor is provided with a resistance body (11), a pair of main electrodes (12, 12) separated from the resistance body, and a pair of voltage detection electrodes (13, 13) separated from the main electrodes. The voltage detection electrodes (13) are provided and fixed between the resistance body (11) and the main electrodes (12). The voltage detection electrode (13) is provided with a detection terminal (13a) to be connected to a terminal of a voltage detection circuit. The resistance body (11) has a columnar shape. The voltage detection electrode (13) and main electrode (12) are fixed to both end faces of the resistance body (11) in the length direction, so that they are opposing each other. The components are bonded by diffusion boding, friction bonding, wax bonding, etc., after abutting the bonding surfaces with each other.
    Type: Grant
    Filed: May 17, 2012
    Date of Patent: June 25, 2013
    Assignee: Koa Corporation
    Inventor: Tadahiko Yoshioka
  • Patent number: 8432248
    Abstract: To provide manufacturing method for resistor that uses metal plate as resistance body, which can obtain desired accurate resistance value without trimming resistance body even if product becomes small. The method comprises; in method for manufacturing an unit resistor that has a pair of electrodes separated by insulation film, from resistor material that is provided with a metal plate consisting of resistance material, an insulation film pattern formed on the metal plate, and an electrode region formed besides area where insulation film pattern has been formed, by piercing predetermined piercing area, wherein length E of insulation film pattern is longer than width w of piercing area, wherein width L of insulation film pattern extends or narrows along direction of length E of insulation film pattern, and wherein position X of piercing area is adjusted in extent and in direction of length E of insulation film pattern.
    Type: Grant
    Filed: February 22, 2012
    Date of Patent: April 30, 2013
    Assignee: KOA Corporation
    Inventors: Hiromu Sakai, Hitoshi Amemiya, Takanori Kikuchi
  • Patent number: 8405318
    Abstract: In a light emitting component, a resistor element is formed on the back surface of a substrate and its resistance value is adjusted to make the light intensity of a light emitting element (LED) in a predetermined range. A constant electric current circuit comprised of the resistor element and a transistor supplies the constant electric current to an LED, and the LED and the transistor are formed on a unit insulating substrate. In the case where the unit insulating substrate is rectangular in shape, one pair of opposite sides are x in length, the other pair of opposite sides are y in length and the ratio value of x/y is in the range of 1-1.25. Further, this light emitting component is provided with two resistor elements and both resistor elements are subjected to a resistor value adjustment.
    Type: Grant
    Filed: February 15, 2008
    Date of Patent: March 26, 2013
    Assignee: Koa Corporation
    Inventors: Michiru Hatakenaka, Takeyoshi Oba, Toshiharu Takayama, Shizuo Yamamoto
  • Patent number: 8324816
    Abstract: An LED driving circuit is provided for making it possible to economically drive a serially connected LED circuit by means of a switching device with a relatively low withstanding voltage even if the number of serially connected LED devices increases. In an LED driving circuit provided with a serially connected LED circuit (11) in which many LED devices are serially connected and a switching device (13) serially connected with the serially connected LED circuit (11) to control that an electrical current flowing through the serially connected LED circuit (11) is turned on or off, wherein a circuit device (15), which comprises a resistor, a constant voltage diode, a constant current diode, or the like, is connected in parallel with the switching device to make a minute current flow through the serially connected LED circuit (11) to the extent that the LED devices are not turned on when the switching device is turned off.
    Type: Grant
    Filed: October 17, 2007
    Date of Patent: December 4, 2012
    Assignee: Koa Corporation
    Inventors: Mitsuo Ohashi, Iwao Sagara, Hideyuki Komatsu
  • Patent number: 8305181
    Abstract: To provide a chip inductor, which can make magnetic loss of the inductor element reduced, excellent in electrical property such as high Q etc., and high reliability, which is demanded for use in vehicles. The chip inductor comprises a ferrite core (11) comprising an axial section (11a), flange portions (11b) disposed at both ends of the axial section, and concavities (11c) opened for direction of the axial section on at least one face of the flange section; an internal electrode (13) consisting of metallic plate having a notch portion at axial section side, the internal electrode fixed on the upper face of the flange section having the concavity; and a winding (12) wound around the axial section of the ferrite core; wherein an end portion of the winding (12a) comes in contact to a side of the concavity, which faces to the axial section, comes in contact to the notch portion of the internal electrode, and is fixed on upper face of the internal electrode.
    Type: Grant
    Filed: June 3, 2009
    Date of Patent: November 6, 2012
    Assignee: KOA Corporation
    Inventors: Masaki Kitagawa, Yukiko Ohta, Miho Kawasaki
  • Publication number: 20120229247
    Abstract: Provided is a shunt resistor which has an excellent accuracy of current detection and a small temperature drift as well as a compact structure, and improves the operability. The shunt resistor is provided with a resistance body (11), a pair of main electrodes (12, 12) separated from the resistance body, and a pair of voltage detection electrodes (13, 13) separated from the main electrodes. The voltage detection electrodes (13) are provided and fixed between the resistance body (11) and the main electrodes (12). The voltage detection electrode (13) is provided with a detection terminal (13a) to be connected to a terminal of a voltage detection circuit. The resistance body (11) has a columnar shape. The voltage detection electrode (13) and main electrode (12) are fixed to both end faces of the resistance body (11) in the length direction, so that they are opposing each other. The components are bonded by diffusion boding, friction bonding, wax bonding, etc., after abutting the bonding surfaces with each other.
    Type: Application
    Filed: May 17, 2012
    Publication date: September 13, 2012
    Applicant: KOA CORPORATION
    Inventor: Tadahiko Yoshioka
  • Publication number: 20120223807
    Abstract: To provide manufacturing method for resistor that uses metal plate as resistance body, which can obtain desired accurate resistance value without trimming resistance body even if product becomes small. The method comprises; in method for manufacturing an unit resistor that has a pair of electrodes separated by insulation film, from resistor material that is provided with a metal plate consisting of resistance material, an insulation film pattern formed on the metal plate, and an electrode region formed besides area where insulation film pattern has been formed, by piercing predetermined piercing area, wherein length E of insulation film pattern is longer than width w of piercing area, wherein width L of insulation film pattern extends or narrows along direction of length E of insulation film pattern, and wherein position X of piercing area is adjusted in extent and in direction of length E of insulation film pattern.
    Type: Application
    Filed: February 22, 2012
    Publication date: September 6, 2012
    Applicant: KOA CORPORATION
    Inventors: Hiromu Sakai, Hitoshi Amemiya, Takanori Kikuchi
  • Patent number: 8203422
    Abstract: To provide a glazed metal film resistor device excellent in TCR characteristics with using an economical base body containing glass by reducing affection to TCR characteristics caused by glass contained in the base body. The resistor device comprises base body 11 containing glass, first protective film 12, which does not contain glass, formed on a surface of base body 11, and thick film resistor 13 formed on first protective film 12. By forming first protective film 12 on a surface of base body 11 containing glass and insulating base body 11 containing glass against thick film resistor 13 of ruthenium oxide as primary component, affection of glass contained in base body 11 to thick film resistor 13 of ruthenium oxide can be suppressed, and change of TCR value from original value of thick film resistor itself can be suppressed.
    Type: Grant
    Filed: November 17, 2008
    Date of Patent: June 19, 2012
    Assignee: Koa Corporation
    Inventors: Takashi Naito, Akihiko Nakamura
  • Patent number: 8149082
    Abstract: The resistor device is provided with a resistive plate (11) of metal plate material, which is used as a resistance body; a radiative plate (15) of metal plate material, which is spaced from the resistive plate and intercrossed on the resistive plate; a molded resin body (19), which encloses an intercrossing portion of the resistive plate and the radiative plate; terminal portions of the resistive plate (11a), which comprises so that both ends of the resistive plate extending from the molded resin body are bent along an end face and a bottom face of the molded resin body; and terminal portions of the radiative plate (15a), which comprises so that both ends of the radiative plate extending from the molded resin body are bent along an end face and a bottom face of the molded resin body. Accordingly, the surface-mountable resin-sealed metal plate resistor device is enabled to increase the power capacity drastically and to improve the reliability without changing most of the size.
    Type: Grant
    Filed: June 26, 2008
    Date of Patent: April 3, 2012
    Assignee: Koa Corporation
    Inventors: Koichi Hirasawa, Hitoshi Amemiya, Atsunori Hayashi
  • Patent number: 8085551
    Abstract: The present invention is to provide an electronic component where positional accuracy for arranging members constituting a circuit element such as a resistor element and the like is mitigated and corrosion of a terminal electrode caused by sulfur in the atmosphere is reduced.
    Type: Grant
    Filed: March 18, 2008
    Date of Patent: December 27, 2011
    Assignee: KOA Corporation
    Inventors: Seiji Karasawa, Koji Fujimoto
  • Patent number: 7968607
    Abstract: This invention relates to skin pore tighteners each of which comprises, as an active ingredient, a compound represented by the following formula: R1—OG ??(1) wherein R1 represents an alkyl or alkenyl group having 8 to 32 carbon atoms, and OG represents a residual group obtained by removing a hydrogen atom from a hydroxyl group of a polyhydric alcohol, monosaccharide or oligosaccharide at least one hydroxyl group of which has been sulfated or phosphatized, or a salt thereof, and also to skin elasticity improvers each of which comprises, as an active ingredient, a glyceryl ether derivative represented by the following formula: wherein R1 represents the same group as defined above, and X1 and X2 each independently represents a hydrogen atom, —SO3OH or —PO(OH)2 with the proviso that X1 and X2 are not hydrogen atoms at the same time, or a salt thereof.
    Type: Grant
    Filed: May 30, 2008
    Date of Patent: June 28, 2011
    Assignee: Koa Corporation
    Inventors: Takafumi Nishijima, Shinya Amano, Tsutomu Fujimura