Hitachi Construction Machinery Co., Ltd.

Hitachi, Ltd.

Tokyo Gas Company Limited

Toshimichi Ikeda

Toichi Hirata

Isao Ishikawa

Kuninori Imai

Takeji Shiokawa

Shigeo Kato

Seiji Tamura

Takeo Iida

Kan Otake

Mikio Aoyama

Etsuji Kosaka

Yasuhiko Haru

Shoji Yoshida

A slide table includes an inner member, an outer member fitted at least partly over the inner member, air bearings provided between the inner and outer members, and a motor means having a coil connected to the outer member to drive the same.

Slide table

A lateral hole boring method whereby a lateral hole of a desired length is formed underground by repeatedly performing the following steps. A vertical hole is prepared, and a lateral hole boring apparatus equipped with a leading auger of a smaller length than the diameter of the vertical hole is lowered into the vertical hole to a predetermined position. The apparatus is manipulated from the ground level to advance and rotate the leading auger to bore a lateral hole. When the lateral hole has reached a predetermined length commensurate with the length of the leading auger, the advance movement of the leading auger is stopped, and the lateral hole boring apparatus is manipulated from the ground level to detach the leading auger therefrom, and is lifted above the vertical hole while leaving the leading auger in the lateral hole. A coupling auger of a smaller length than the diameter of the vertical hole is attached to the lateral hole boring apparatus outside the vertical hole, and the apparatus is lowered into the vertical hole again. Then, the lateral hole boring apparatus is manipulated from the ground level to couple the coupling auger to the leading auger left behind in the lateral hole.

Lateral hole boring method and apparatus

A hydraulic circuit system for civil engineering and architectural machinery having at least first and second hydraulic pumps, a plurality of actuators driven by hydraulic fluid from said pumps, and a plurality of directional control valves for controlling the direction and flow rate of the hydraulic fluid supplied from the pumps to the actuators. In the directional control valves, a first boom directional control valve and one of right and left travelling directional control valves are connected to the first pump in parallel with each other, a swing directional control valve, an arm directional control valve and a second boom directional control valve are connected to the second pump in parallel with one another, and the other of the right and left travelling directional control valve is connected in tandem to the swing, arm and second boom directional control valves at a location downstream thereof. A connecting line is provided for communication between an inlet port of the one travelling directional control valve and an inlet port of the other travelling directional control valve.

Hydraulic circuit system for civil engineering and architectural

Growing community of inventors

Ibaraki, Japan

Toshimichi Ikeda