| 摘要 |
PURPOSE:To preven the occurrence of rotational vibration of a rod with stirring blades by inserting the rod into an outer cylinder with an auger in a vertically movable and turnable manner. CONSTITUTION:A rod 1 with a sidewardly turnable stirring blade 2 is inserted into an outer cylinder 3 with an auger 7 in a vertically movable and turnable manner. In improving the ground, the blade 2 is turned downwards and advanced in ballast B while turning the rod 1 and the outer cylinder 3. When the outer cylinder 3 reaches the bottom of the ballast B, the rotation and lowering movement of the outer cylinder 3 are stopped, the rod 1 is only advanced rotationally, and an improving agent is discharged under the condition that the blade 2 is opened. Since the auger 7 is preveted from biting into the ballast B, the outer cylinder 3 can be kept in stabilized state, no slackening occurs in the ballast B, and the turning of the rod 1 can be prevented. |
