THRUST CONTROLLER OF THRUSTING JACK AND TUNNEL EXCAVATOR

摘要

PROBLEM TO BE SOLVED: To carry out an accurate directional control even in ON/OFF control, by controlling the opening/closing of two changeover valves and a pressure control valve in accordance with an objective action point of a tunnel excavator body. SOLUTION: A plurality of shield jacks 14 thrusting an excavator body 11 and a cutter head 12 are parallelly arranged along the circumferential direction, at the rear part of the excavator body 11. The thrust force of the fourteen shield jacks 14 is adjusted and controlled by a thrust controller 15 to control the excavating direction of the excavator body 1. In ON/OFF control of these fourteen shield jacks 14, hydraulic oil is directly supplied from a hydraulic pump by the opening operation of the first changeover valve 30 corresponding to the shield jack 14 turned ON. The control pressure is set to actuate respective shield jacks 14 by the closing operation of the first changeover valve 30 corresponding to the shield jack 14 turned OFF, the opening operation of the second changeover valve and the pressure adjustment of a relief valve 31.