Hitachi, Ltd.

Tokyo Gas Company Limited

Shinichi Kurita

Seishi Watahiki

Yasuzi Sakuma

Masayoshi Yamaguchi

Takashi Yamade

Atsuo Watanabe

Norio Ishitsuka

Masahiro Ito

Kiyoshi Sakamoto

Atsushi Takagi

Mitsutoshi Honda

Chikara Sato

Toshihito Tabata

Hidekazu Kamioka

A dielectrically isolated semiconductor device of high reliability is provided by realizing a fine and deep element isolating region which can prevent dislocation of an oxide film as an insulation layer by oxidation-induced stress. The dielectrically isolated semiconductor device includes an SOI substrate supporting an active element layer deeper than an expanded distance of a depletion layer subjected to the highest voltage applied to the device, and an element isolating region which encloses the active element layer. The element isolating region contains a deep trench which comes into contact with the insulation layer, and which is filled with n heavily doped layers on both side walls, second insulation films each adjacent to the n heavily doped layer and a polycrystalline semiconductor layer formed between the second insulation films.

Dielectric material separated-type, high breakdown voltage semiconductor circuit device, and production method thereof

A plasma welding method has successive steps including pre-heating of members to be welded, tack welding of the members for tentatively fixing these members, keyhole welding for completely welding the members to each other, and finish padding. These steps are automatically conducted by a single plasma welding apparatus operative in accordance with a programmed sequence including data concerning the optimum conditions of operation in each step in relation to the conditions such as sizes and materials of the members to be welded. The apparatus has a welding torch, a welding head on which the welding torch is mounted for rotation, a controller adapted for storing the optimum welding conditions for successive steps of the welding process in relation to the conditions of the members to be welded, a power supply system for transmitting welding current and welding speed signal to the welding head in accordance with a command provided by the controller, and a gas supply system for supplying a plasma gas at a rate determined in accordance with a command from the controller.

Method of and apparatus for conducting plasma welding

Method of and apparatus for automatically conducting all position plasma

A piping travelling apparatus having a plurality of continuous treads driven by motors through transmission gearing. The continuous treads are mounted to a frame and spaced apart a predetermined distance peripherally of the inner wall surface of the piping. At least one of the continuous treads is kept in contact with the inner wall surface of the piping no matter what the posture of the apparatus may be, so that the apparatus can travel without any trouble even if its posture undergoes a change when it moves along elevations and depressions on the inner wall surface of the piping or negotiates the boundary between different levels of the inner wall surface or bends of the piping. The apparatus enables a travel through piping of relatively small diameter having vertical or steeply slanted pipes to be made without any trouble.

Piping travelling apparatus

Growing community of inventors

Mito, Japan

Shinichi Kurita