Apparatus for the excavation of subterranean tunnels

摘要

Tunnel excavating apparatus comprises a hollow cylindrical shield adapted to be axially forced through subterranean material and having a circular cutting edge at a leading end portion. An inclined baffle and guide member has a central opening spaced upwardly from a lower edge of the baffle and guide member and an auger-like member extends across the shield adjacent the opening. Sections of the auger-like member extending on horizontally opposite sides of the baffle opening have oppositely directed flutes and subterranean material dislodged by the cutting edge and deposited atop and about the auger is urged inwardly toward the opening in the baffle and guide member for deposition on a conveyor having a receiving end beneath the opening. The conveyor extends rearwardly and upwardly and deposits the material in a receptacle. Horizontal and vertical breasting plates also serve to cut and dislodge material and support the shield. A rotary cutter above the auger-like member also assists in cutting the subterranean material. The cutter is movable from a position within the shield to a position forwardly of its cutting edge.