| 摘要 |
<p>A machine is disclosed for cleaning up the roofs and working faces of underground galleries tunnelled by blasting. The machine comprises a selfpropelled chassis, preferably equipped with pneumatic-tyred wheels connected to the chassis by pivotable arms, a platform arranged below the chassis being designed to rest upon the ground and thus to support the machine when it is in operation. A first lever, constituting a boom and adapted to pivot vertically in order to adjust the operable height, is hinged to the chassis. A second lever, the arm, adapted to pivot horizontally, is hinged to the free end of the first lever. A third lever, the tool proper, is hinged to the end of the arm. The movements of the levers are controlled by jacks for the purpose of moving the tool along the walls.</p> |
