Abstract: Disclosed herein is an exchangeable needle cartridge for a drilling measuring device with a guiding device for a drilling needle. The guiding device includes a telescopic tube with a plurality of telescopic tube sections which extends between a working end, at which a retainer for retaining the drilling needle in a rotationally fixed manner is arranged, and a docking end, at which a docking device for coupling the telescopic tube to a driving device of the drilling measuring device is arranged. Also disclosed is a docking device comprising a coupling device for transmitting torque from the driving device of the drilling resistance measuring device to the telescopic tube, a transmission device for converting the rotational motion of the driving device of the drilling measuring device into a linear motion of the telescopic tube, and furthermore structure for detachably fastening the exchangeable needle cartridge to the drilling measuring device.

Abstract: The present invention provides an instrument and a method for examining the condition of column-shaped or cylindrical sections of objects. It comprises a drive device having a drill chuck, which holds a drill needle that can be driven by the drive device, and a guiding device for guided insertion of the drill needle into the object to be examined. The guiding device is a telescopic tube that comprises a shorter inner tube section that is arranged in a longer outer tube section such that it is axially displaceable, and has a longitudinally arranged measuring scale on its outer circumference. The telescopic tube is placed on the drive device in non-rotating manner via the inner tube section. The inner and the outer tube sections have guiding means for centrally-axially guiding the drill needle, which extends in central-axial direction from the drill chuck through the inner tube section and through the outer tube section.