Ihi Corporation

Tokina Optical Co., Ltd.

Isao Kawaguchi

Koutarou Inose

Hiroto Yamaoka

Tomohiro Sugino

Shiro Saito

Junko Kambayashi

Yasumasa Nakanishi

Shin Ikeda

Masakuni Tai

A method of forming stiffened plate by welding a plurality of stiffener materials and a steel plate, so that closed cross-sectional structures are secured onto a surface of the steel plate. The stiffener materials are joined to the steel plate as a result of edge portions of the stiffener materials which are in contact with the steel plate by being laser welded at a predetermined welding speed as a result of a laser having a predetermined output being irradiated from a predetermined direction thereon from the external side of the closed cross-sectional structures. Accordingly, it is possible to achieve an improvement in the weld quality when welding stiffener materials onto a steel plate, and to achieve an improvement in fatigue strength.

Method of manufacturing a stiffened plate by hybrid laser arc welding

An end face () of one () of two adjacent thick steel plates () intended to construct a corner joint of a bridge column is formed into a beveled end face (). Laser beam welding is applied to a root portion () of the beveled end face, and arc welding is applied to bevels () thereof so that grooves defined by the bevels () are filled with weld metal ().

Corner joint structure for bridge pier and method of producing the same

A telephoto zoom lens system comprises a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a third lens group having a positive refractive power. In a zooming operation, the first lens group moves arithmetically, the second lens group moves from the objective side toward the image side in the first half of the movement and then from the image side toward the objective side in the latter half of movement, and the third lens group moves so as to maintain the image side focal point thereof in a fixed position in conjunction with the first and second lens groups.

Telephoto zoom lens system for camera

Growing community of inventors

Yokohama, Japan

Isao Kawaguchi