| 摘要 |
PROBLEM TO BE SOLVED: To provide technology for removing foreign matter inside a hole, allowing certain discharge of the foreign matter present inside the hole outside the hole with small man-hours.SOLUTION: Foreign matter removal is executed in a process of inserting a nozzle 20 into a hole 25 in (b), and jetting air to the bottom 26 of the hole 25 from the nozzle 20; and a process of moving the nozzle 20 outside the hole 25 while jetting air in (d). When moving the nozzle 20 outside the hole 25 in a state that the air becomes easy to flow out from inside the hole 25, foreign matter 27 present inside the hole 25 can be carried outside the hole 25 by the air, and the foreign matter 27 is certainly discharged outside the hole 25. A fluid is jetted from the nozzle 20 inside the hole 25, and the nozzle 20 is only moved outside the hole 25 as it is, so that the foreign matter 27 present inside the hole 25 can be certainly discharged outside the hole 25 with small man-hours. |
