| 摘要 |
PROBLEM TO BE SOLVED: To smoothly convey earth upward in execution of suction conveying. SOLUTION: There are provided earth conveying facilities in which a valve 11 for supplying air or interrupting air supply to an intake pipe 7 is arranged across the intake pipe 7 at a location in the vicinity of a lower end of a vertical shaft TR1. When an earth plug PG is clogged at the vertical shaft TR1, the valve 11 is opened to introduce air to an upstream portion of the plug PG, to thereby increase a difference in pressure. |
