| 摘要 |
<p>The front end portion of an endless belt type conveyor is detachably connected to the floor of a self-propelled tunneling shield, and the rear end of the conveyor is supported inclined upwardly by a trailing, mobile power unit which rides on spaced apart rails disposed along the tunnel floor. A pair of double acting hydraulic cylinders advance and retract a boom supporting carriage along support rails mounted along the length of the conveyor. An elongate boom is mounted on the carriage for movement with the carriage toward and away from the tunnel face. A combination digging and hoeing excavator tool is carried by the front end portion of the boom to loosen material at the tunnel face and then hoe the loosened material rearwardly onto the conveyor.</p> |
