| 摘要 |
<p>The milling cutters (3, 4) are suspended on pivot arms (15, 16). Those pivot arms (15, 16) are pivotably mounted to an intermediate support structure (18). The pivot axes (24) of the pivot arms (15, 16) extend perpendicularly to the axes of rotation (3, 4) of the milling cutters (3, 4). These pivot arms (15, 16) are operated by hydraulic actuators (20). Therefore, in operation the milling cutters (3, 4) will oscillate over the bottom of a trench (11) being excavated such that no center ridge remains at the bottom of the trench which would call for additional operational procedures in order to be removed. Furthermore, the intake (35) of the suction pipe (34) for the removing of the milled off matter by means of a slurry being circulated is located close to the zone where the milling takes place. Therefore, the efficiency of the circulated volume of the slurry regarding the volume of milled material taken along is much improved. Because the milling cutters (3, 4) can pivot, their thickness can be smaller in spite of covering the complete width of the trench being excavated. Accordingly, they can act with a much higher pressure per surface unit onto the ground, thus enabling the use of rock bits such that also hard rock can be milled. <IMAGE> <IMAGE></p> |
