Nittetsu Jitsugyo Co., Ltd.

Nitto Electric Industrial Co., Ltd.

Takatoshi Hamada

Wen-Ho Huang

Miho Yamaguchi

Satoshi Ito

Akiko Kitayama

In the hydraulic breaker according to the present invention, oil pressure at a fixed value always flows in the circuit at a low pressure side whenever the piston is raised or lowered, to prevent the need for an accumulator in the circuit at the low pressure side. At the same time, a high pressure oil is required during the raising and lowering of the piston, bringing about less of a change in the surge pressure, attributing to the fact that there is no need for an accumulator in the circuit at the high pressure side. Moreover, the hydraulic breaker of the present invention is advantageous by providing an increased striking force because the high pressure oil is used, in addition to the reaction force of the compressed nitrogen gas, when the piston is lowered to strike the chisel.

Hydraulic striking device with impact frequency control

A semi-conductor device in which a semi-conductor element is sealed with a molding resin is disclosed. In the device, adhesion between a semi-conductor chip and the molding resin is achieved mainly by oxygen-crosslinking between silicon in the semi-conductor chip and silicon in the molding resin. The device exhibits excellent moisture-resistant reliability even after mounting.

Growing community of inventors

Osaka, Japan

Takatoshi Hamada