| 摘要 |
PURPOSE:To accurately judge whether or not the drilling direction of a hole is on a perpendicular line by providing a drill pipe which is driven to rotate, a cutting means which is fixed to one end part of the pipe, and inclinometers fitted to one end part of the drill page. CONSTITUTION:While the hole 16 is drilled, both inclinometers 28 receive equal centrifugal force generated by the rotation of the drill pipe 12 on condition the axis of the drill pipe 12 is perpendicular and output an equal value. When the axis of the drill pipe 12 is not perpendicular, on the other hand, both inclinometers 28 slant together wit the drill pipe 12 and the output values of both inclinometers 28 are different. It is confirmed whether or the drill pipe 12 is perpendicular, namely, whether or not the hole 16 is drilled perpendicularly by checking whether or not the outputs of both inclinometers 28 is equal. |
