| 摘要 |
PROBLEM TO BE SOLVED: To carry out the smooth excavation of a gripper shoe along a bedrock by a small number of jacks by installing a gripper shoe base contacted or separated with or from a tunnel pit wall to a gripper jack mounted on a gripper carrier and setting up the split type gripper shoe to the gripper shoe base in a rockable manner. SOLUTION: A gripper device 5 is fitted at the rear section of a main beam 1 longitudinally slidably through a thrust jack to a cutter head support. The base end section of a gripper jack 7 is installed to a gripper carrier 6 for the gripper device 5, split type gripper shoes 8B are mounted on a pair of left-right gripper shoe bases 8, 8 set up at the front end sections of the gripper jack 7 in a rockable manner by pins 8A, and the gripper shoe bases 8, 8 are contacted or separated with or from a tunnel pit wall. When the gripper shoe bases 8 are moved towards the pit wall by operating the gripper jack 7, each gripper shoe 8B is rocked along the curvature of the pit wall, and fast stuck on the pit wall even when the excavation diameter of the pit wall is changed. |
