| 摘要 |
PROBLEM TO BE SOLVED: To propel a propelling element accurately without executing complex direction control. SOLUTION: A propelling element S is used which comprises a propelling head 1, with a pressure receiving face part F inclined relative to a head axis P, and a plurality of propelling pipes 2 joined to the rear of the propelling head 1 in such a way that they are freely curved. To propel the propelling element S into the ground by applying pressure from behind, the propelling element S is designed so that the curving axes X of each propelling pipe 2 are the same, and the propelling element S is propelled with the pressure receiving face part F oriented in the oscillating direction of the propelling pipes 2 around the curving axis X. |
