OBSTRUCTION CUTTING DEVICE FOR SHIELD MACHINE

摘要

PURPOSE: To remove an obstruction positively only by an excavator by providing a roller cutter with roller edges arranged in the direction intersecting the radial direction of a cutter head, and making the roller cutter movable forward and backward in the vertical direction of the cutter head. CONSTITUTION: A cutter head 1 provided with sediment excavating bits 6 is provided with a roller cutter 12 with roller edges arranged in the direction intersecting the radial direction of the cutter head 1 and rotated by a hydraulic motor. This roller cutter 12 is advanced/retreated in the vertical direction of the cutter head by a hydraulic cylinder. The roller edges of the roller cutter 12 are thereby brought into intersecting contact with an obstruction by the rotation of the roller head 1 so as to cut the obstruction while being rotated. The roller edges are raised only at the time of cutting the obstruction and not used for normal sediment cutting, so that the wear of the roller cutter 12 is reduced, and the service life can be prolonged.