| 摘要 |
PROBLEM TO BE SOLVED: To provide a shield machine capable of preventing oil pressure of two hydraulic jacks for driving a beam cutter from rising competitively. SOLUTION: In this shield machine, opening degrees of first control valves 48a, 50a are controlled to make deviation of a stroke detected value of the first hydraulic jack 40a detected by a first stroke detection means 54a from a stroke set value of the first hydraulic jack 40a zero, a jack thrust set value of the second hydraulic jack 40b fixed in accordance with deviation of a stroke detected value of the second hydraulic jack 40b detected by a second stroke detection means 54b from a stroke set value of the second hydraulic jack 40b is decided, a jack thrust calculated value of the second hydraulic jack 40b is decided based on an oil pressure detected value of the second hydraulic jack 40b detected by second oil pressure detection means 55b, 56b, and opening degrees of second control valves 48b, 50b are controlled to make deviation of the jack thrust calculated value from the jack thrust set value zero. COPYRIGHT: (C)2009,JPO&INPIT |
