Cutting Device with Function of Changing Diameter in Small Range for Soft Rock Shield Machine

A cutting device for a tunnel boring machine comprising a cutting head, a plurality of peripheral cutters mounted on said cutting head, at least one peripheral cutter driving mechanism, a hydraulic control system, and a dissipation monitoring system, wherein the cutting device is characterized in that said cutting head has at least one groove, wherein said peripheral cutters are symmetrically mounted on said cutting head at two sides of said groove, wherein said peripheral cutters are connected with said peripheral cutter driving mechanism which is provided on said groove, wherein said hydraulic control system comprises a fluid tank arranged to drive said peripheral driving mechanism to move for driving said peripheral cutter to move correspondingly, wherein said hydraulic control system further comprises a control head, a motion sensor electrically connected to said control head through a plurality of electrical wires, wherein said control head is communicated with said fluid tank through a plurality of transmission tubes and a fluid outlet, wherein said dissipation monitoring system comprises a detection probe provided on said cutting head, an alarm device, and a plurality of wires extended between said detection probe and said alarm device for generating an alarm signal when said detection probe is dissipated beyond a predetermined threshold.