Honda Motor Co., Ltd.

Yosuke Hiruma

Yusuke Muramatsu

Keishi Setoda

Tatsuro Ikeda

Akira Goto

Shinichi Miyasaka

Takahiro Morita

A plasma ejection unit () of an arc welding device includes a plasma torch (), a copper plate (), a container (), and a gas supplying unit (). Plasma gas inside the container () is pressurized by argon gas supplied from the gas supplying unit (), and ejected from first to eighth ejection ports. The plasma gas ejected from the first to eighth ejection ports is concentrated in a concentration area (CA) between vehicle body plates (-) to form through holes () in the vehicle body plates (-), and is separated. The air pressures, in eight areas, of the plasma gas reaching a vehicle body plate () are approximately one-eighth of the air pressure of the plasma gas in the concentration area (CA). Accordingly, while the through holes () are formed in the vehicle body plates (-), no through hole is formed in the vehicle body plate ().

Arc welding device and method

A penetration welding method includes a plasma welding step for forming a through hole in a work, which is a laminated steel plate, from a front surface to rear surface thereof without forming a hole in a component at the rear, by generating a plasma arc column from a plasma torch to the work. After the plasma arc column is generated, the plasma arc column is extinguished when an arc voltage or the length of the arc estimated from the arc voltage exceeds an end-determining threshold which is determined according to the thickness of the work. Further, plasma gas is discharged from the plasma torch at a flow rate at which the width of the plasma arc column is maintained approximately constant from the plasma torch side to the work side so that the arc voltage is increased at an approximately constant rate before and after penetration.

Penetration welding method

The invention provides a switching electrode which has a small variation in resistance value even when a large amount of current is repeatedly cut off and can carry a stable amount of current even when it is continuously used. In the invention, the switching electrode is used in a switch which includes a first switching electrode tip () and a second switching electrode tip (), brings the first switching electrode tip () and the second switching electrode tip () into surface contact with each other to carry a current, and separates the first switching electrode tip () and the second switching electrode tip () to cut off the current. At least one of contact surfaces of the first switching electrode tip () and the second switching electrode tip () is a flat surface having an uneven portion.

Growing community of inventors

Tochigi, Japan

Yosuke Hiruma