| 摘要 |
<p>PURPOSE:To enable to change shapes of excavated cross sections consecutively and automatically, by turning the entire body of a shield excavator while making evacuating operation ahead simultaneously with offset from plural shield drums in a row each other in a tangent direction. CONSTITUTION:Plural shield drums 2 and 3 arranged in a row are offset from each other in a tangent direction to make excavating operation ahead simultaneously and a rotation moment caused by a difference in excavating directions turns the entire body of a shield excavator. As head cutters 7 and 8 on the front of shield drums 2 and 3 make excavating operation ahead, side cutters 16 installed on the recess of adjoining shield drums excavate a convexity between the shield drums and turns the entire body of the shield excavator. And then, as the head cutters 7 and 8 make excavating operation ahead, supplement cutters 10 which are arranged at the outer edges of the shield drums, excavate convexities at the outer circumference. This can make control of a direction easy.</p> |
