Koa Corporation

Koichi Hirasawa

Keishi Nakamura

Kenji Kameko

Yoshinori Aruga

Tadahiko Yoshioka

Shuhei Matsubara

Hitoshi Amemiya

Katsumi Takagi

Hirotoshi Aoki

Katsuhide Nishizawa

Atsunori Hayashi

The present invention relates to a jumper element, a shunt resistor apparatus, and a method of adjusting characteristic of a shunt resistor apparatus for current detection. The jumper element () for constituting the shunt resistor apparatus for current detection is made of conductive metal material. The jumper element () includes: a body structure () that can be coupled to a resistance element () constituting a part of the shunt resistor apparatus; and a protrusion () formed on a side portion of the body structure (), wherein the protrusion () is located so as not to overlap the resistor element ().

Jumper element, shunt resistor apparatus, and method of adjusting characteristic of shunt resistor apparatus for current detection

A thermal analysis model includes an intermediate node that imitates an intermediate portion and a first thermal resistance connecting to the intermediate node, and imitates the terminal portions on both sides. A terminal portion inside node connected to the first thermal resistance is configured to imitate an inside area adjacent to the intermediate portion and serves as a starting point of a first heat dissipation path to the substrate. A terminal outside node is configured to imitate an outside area separated from the intermediate portion and adjacent to the inside area in the terminal portions and serves as a starting point of a second heat dissipation path to the substrate. A second thermal resistance connects the terminal portion inside node and the terminal portion outside node and is arranged parallel to a different element imitating a thermal resistance of an electrode layer in a surface of the substrate.

Non-transitory computer-readable recording medium and thermal analysis device

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 () that has a pair of electrodes () at both ends of a resistor body (); a connector base () formed of insulating material; and an electrically conductive section () formed on the connector base (); wherein the connector base () is fit onto the shunt resistor () such that the electrically conductive section () is electrically connected to the electrodes (). The connector base () is provided with a joint section (C) that can be fit onto the resistor body (). The resistor body () and the electrode () is provided with a level difference and the connector base () is fit into between the electrodes ().

Terminal connection structure for resistor

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 () and at least a pair of electrodes (), wherein the resistor body () is configured in a pillar-shape having diameter of 4 mm or less disposed between the electrodes. Each of the electrodes () 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 () is square pillar-shaped, and the resistor body is fixed to roughly to center of the electrode in cross-section.

Current detection resistor

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 (); a pair of electrodes () fixed to each end of the resistance body; and a pair of voltage terminal members () for detecting voltage generated in the resistance body and that are connected to each electrode; wherein the voltage terminal member () includes a connecting portion () for connecting to the electrode (), an extending portion () 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.

Resistor for detecting current

Provided is a resistor for current detection, wherein connection failure etc. due to electro-migration is prevented from being generated in state that the resistor is mounted on a mounting board. The resistor has a resistance body () and electrodes (). The electrode () includes first electrode portion () connected to the resistance body () and second electrode portion () formed on the first electrode portion (). The second electrode portion () consists of material having higher resistivity than the first electrode portion () and solder, which is used for mounting the resistor on the mounting board.

Resistor and structure for mounting same

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 (), and a pair of main electrode (), of another material from the resistance body, wherein end faces of the resistance body and the main electrode are bonded. The resistance body () has a hole () going through in direction where main electrodes are disposed, or a high resistance part () going through at its axis portion that is highly resistive than outer part, and low resistance part () 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.

Shunt resistor and method for manufacturing the same

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 (); a pair of main electrode () for flowing current to be monitored through the resistance body; a pair of detection terminal () for detecting voltage caused in the resistance body; and a pair of wiring () each electrically connected to the detection terminal. And, a pair of voltage detection wiring consisting of the detection terminal () and the wiring () is brought closer, at prescribed location, than distance between each of connection position of the pair of the detection terminal () on the main electrode (). A low-pass filter having resistance value (r) and capacitance (C) is provided at next stage after the pair of the wiring, and said low-pass filter having a relationship Le/R=C&#xb7;r, when Le (=L&#x2212;M) is the effective inductance, and R is the resistance value of the resistance body.

Shunt resistor device

The resistor device is provided with a resistive plate () of metal plate material, which is used as a resistance body; a radiative plate () of metal plate material, which is spaced from the resistive plate and intercrossed on the resistive plate; a molded resin body (), which encloses an intercrossing portion of the resistive plate and the radiative plate; terminal portions of the resistive plate (), 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 (), 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.

Resistor device

A resistive element in the form of a bent metal plate is placed in a box-shaped case and has electrodes exposed out of the box-shaped case. A heat radiator in the form of a bent metal plate is also placed in the box-shaped case and has heat radiating electrodes exposed out of the box-shaped case. The resistive element and the heat radiator are held out of contact with each other and disposed in criss-cross relation to each other. The box-shaped case is filled with a cement material in surrounding relation to the resistive element and the heat radiator.

Cement resistor

A mounting structure for current detection resistor device has a feature that voltage detection terminal wiring is configured so as to extend along a current path in the resistor body first, and then, to bend at right angles to the current path, while maintaining electrical isolation from a resistor body of the current detection resistor device. The voltage detection terminal wiring connecting to the voltage detection terminals on the circuit board is disposed to extend for some distance in the same direction as the current path so as to cause mutual-inductance between that section of the voltage detection terminal wiring and the resistor body. This causes cancellation of induced voltage caused by the self-inductance of the resistor body, so that it is possible to nullify detection error generated by the voltage induced by the resistor body from the viewpoint of the measuring system. Therefore, it is possible to detect a large current with good accuracy that may flow in a device such as a current detection resistor device for a switching power source operating at high frequencies. A method is provided for measuring a value of effective inductance that includes the steps of: supplying a flow of current to be measured having a saw-teeth waveform through a resistor device to simulate the actual use; detecting a flow of current and detecting a voltage produced by the flow of the current; and computing an effective inductance value from a variation in the flow of saw-teeth waveform current and a corresponding variation in the voltage.

Growing community of inventors

Ina, Japan

Koichi Hirasawa