Drillhole surveying device

摘要

A drillhole surveying device is indicated, in which a probe consists of at least three probe sections (15, 16, 17) mutually joined in an articulated, but torsionally rigid manner, which probe is moved stepwise by a movement device (8) through a drillhole (7). The step length (1) corresponds to the same distance from joints (10 to 14) of adjacent probe sections (15 to 17). The angle between the adjacent probe sections is measured by means of an angle-measuring arrangement (40) and evaluated, preferably digitally, and stored in a memory (54) on site. From the plurality of angle values obtained for each measuring point, the rotation of the probe (9) in the drillhole (7) is determined, and from this the actual course of the drillhole (7) is in turn determined. The digital signals corresponding to the angle values are stored in addressable memory locations and, after completion of the total measuring procedure, called in and processed in a computer to determine the actual course. The angle-measuring arrangement (40) advantageously has an optical transmitter (43) and a semiconductor-based photoconductive receiver (44). By using microprocessors and semiconductor elements, an extremely small overall length can be achieved, so that drillholes (7) having diameters of less than 40 mm can be surveyed. <IMAGE>