| 摘要 |
PURPOSE:To permit the excution of earth auger operation on the same imaginary circumference by using a system in which two auger screws set on the outside can be set at any angle within a given angle range from front face side to rear face side in relation to two auger screws on the inside. CONSTITUTION:The first and second rotary shafts 16 and 25 to be driven by an auger screw driver source (not illustrated) are pivotally supported in the first and second fitting frames 15 and 21 in the inside of a vertically movable frame 5 hung by a hanging mechanism 9 and supported by a guide rail provided along a leader 3. The rotary shafts 16 and 25 have integrally formed couplers 12a and 12b at their lower ends, and auger screws 12 are detachably provided to the couplers 12a and 12b. Furthermore, a cylinder 31 is interposed between the frames 5 and 21, and by extending or contracting them, the frame 21 is horizontally moved in a rocking manner (at angle theta) around the shaft 16 in such a way as to enable the screws 12 to be switched from a straight arrangement to a circular arrangement. |
