| 摘要 |
<p>Circular heading machines for excavating tunnels by advancing a machine in step-wise fashion and erecting tunnel supports. The circular heading machine has an elongate machine body (10) at the forward end of which a forwardly directed cutter boom (11) is mounted, rams advance the machine body in step-wise fashion acting against grippers (23) and a profile ring (18, 18') limits peripheral movement of the cutter boom to form an accurate profile. A gathering apron (16) is provided at the forward extremity of the machine body. The cutter boom (10) is mounted on a sliding carriage (12) longitudinally movable on and independently of the machine body and a hood (17) overlies the apron. A cage structure (21) extends rearwardly from the hood structure and surrounds the boom cutter (11) and sliding carriage (12) and tunnel support erecting means (20) are provided externally of the cage structure, directly behind the hood structure. Thus the tunnel support structures are erected over the machine body rather than behind the machine, and also erection of the tunnel support structures takes place simultaneously with operation of the cutter. The hood (17) is a semi-circular member supported by hydraulic rams (17A) for height adjustment.</p> |
