| 摘要 |
<p>The invention relates to an advancing device for boring sections of roadway, tunnels or similar, with a working head (100) comprising first rotary cutter s which are distributed over the surface that faces the working face (O), with in the outer periphery of said working head and which are designed to loosen th e solid material on the working face (O); and second rotary cutters (2) which protrude beyond the outer periphery to advance an overcut. According to a first embodiment of the device, the second rotary cutters (2) have a greater outer diameter than the first rotary cutters (1). According to a second embodiment, the fixing devices for the second rotary cutters comprise elemen ts which allow said second rotary cutters to be mounted optionally in positions projecting radially to different distances beyond the outer periphery of the working head.</p> |
