| 摘要 |
PURPOSE:To excavate a large sectional tunnel peripheral part deep in selecting the expansion or contraction of a boom and the bending angle of a cutter optionally by constituting the boom with both inner and outer cylinders, and connecting the cutter to the boom through a hinge. CONSTITUTION:A tunneling machine is constituted of a boom 3 connecting those of excavator body 1, turntable 8, a boom turning jack 10 and cutter 4, and a boom vertical jack 11. This boom 3 is made up of an outer cylinder 12 and an inner cylinder 13 supported free of relative displacement in both axial and rotational directions at the inside. Next, there are provided with a boom expanding jack 19 expanding and driving these cylinders and a hydraulic motor 18 relatively rotating them. In addition, the cutter 4 is connected to the boom 3 through a hinge, and a connective angle is made optionally alterable by an arm jack 25. Then, expansion or contraction of the boom 3 and a bending angle of the cutter 4 are optionally selected. |
