| 摘要 |
PROBLEM TO BE SOLVED: To provide a measuring apparatus for the position of an underground boring machine, by which an operation to shine light at a position detecting element is eliminated in measuring operation and in which mechanical measuring errors or a measuring error due to a vibration are hardly generated. SOLUTION: A measuring reference point, a second measuring reference point, one or more intermediate measuring points and a point to be measured are set sequentially. Light sources are installed in the measuring reference points. In addition, a measuring unit 300, which is provided with a common lens 411 used to condense beams of diffused light from a front light source 41 and a rear light source 42, which is provided with a position-detecting element 412-2 and a position-detecting element 412-1 used for detected the light-receiving position of light condensed by the lens, which is provided with a reflecting prism 413-1 and a reflecting prism 413-2 used to guide the light to the respective position detecting elements, after the beams of diffused light incident on the lens are condensed by the lens and which is provided with the light sources 41, 42 used to direct the beams of diffused light to the front and the rear by using the respective reflecting prisms is installed at every measuring point, after the second measuring reference point onward. On the basis of the position of the second measuring reference point which is measured in advance and of the detected result at every measuring point and of the distance between respective measuring units which are measured separately, the position of the point to be measured, with respect to the measuring reference points is measured. |
