| 摘要 |
PROBLEM TO BE SOLVED: To easily and reliably improve durability of a valve element, on a soil discharge valve used for a shield machine.SOLUTION: A coaxially inserted cylindrical flexible sheet shield body 13 is inserted inside a valve element 12 of a soil discharge valve 10, and the inside of the shield body 13 is formed as a passage of excavation soil, and only an inlet side end part of the excavation soil of the shield body 13 is fixed to the valve element 12. Since the excavation soil flows inside the valve element 12, it does not directly contact the valve element 12, so that abrasion and a broken hole of the valve element 12 are prevented.SELECTED DRAWING: Figure 2(A) |
