Abstract: A guide device for linear guidance of elongated objects, particularly for positioning wires passing a nondestructive eddy current test device, can be the inlet nozzle or outlet nozzle, and has a brush arrangement integrated into a guide sleeve. The brush arrangement damps vibration of the wires or other elongated objects transiting the test device. A wire guided by the guide device is protected at its surface and subjected to little or no transverse vibration in the vicinity of the test probe of the test device, resulting in improved measurement accuracy.

Abstract: In a quality monitoring method it is proposed that in continuous operation a test signal be generated, digitized, logarithmized, followed by the calculation of a frequency distribution of the test signal amplitude. The frequency distribution can then be integrated in individual areas, the result for each area forming a feature of the test signal. The features of a test signal are combined into vectors, which can be used for a better evaluation of the quality of the production plant.

Abstract: A method and apparatus for testing an elongate product for faults and defects, which comprises a rotatable testing head which permits the elongate product to be passed coaxially therethrough and which mounts a pair of testing probes so as to permit adjustment of their operating diameter. In order to automatically adjust the positions of the probes to accommodate elongate products of different sizes, there is provided an external adjustment unit, which stops the testing head in a predetermined angular position. The adjustment unit contains an external adjustment drive and when the rotation of the testing head has stopped, the external adjustment drive is advanced into operative engagement with the adjustable mounting of the testing probes.

Abstract: A device for testing elongated objects, particularly wires, optionally with cross-sectional irregularities, which has a rotating test head traversed by the object and on which is provided a probe, particularly an eddy current probe, provided on rotary probe holding means and guided on circular paths about the object. For the change of the radial spacing between the object and the probe with the test head rotating, externally controllable e.g. by a sensor for irregularities, the device has a switching device with two inherently stable switching states, whereof one can correspond to a testing position near the object and another to a raised position further removed from the object and which can be rapidly set for protecting the probes.

Abstract: A search coil assembly for an inductive search device is described having a hield formed from a carrier layer and a thin metal coating applied thereupon, in which the coating is arranged into a plurality of parallel circuit tracks. The circuit tracks are electrically connected to one another by connecting tracks and to a reference potential. The described search coil assembly can be advantageously constructed by multi-layer circuit board technology.

Abstract: Detection of both surface defects of a non-ferromagnetic test body as well s the presence of ferromagnetic particles in the test body by inducing eddy currents and D.C. fields in the body. The resulting signal voltages are filtered and separately examined.

Abstract: Method and apparatus for scanning an object with a probe in which scanning lines for the forward and backward motions run parallel to each other and their mutual spacing from each other remains constant. In one form, the object transportation speed Vt is set relative to the speed Va of the forward and backward motions in such a way that Vt/Va=tangent .alpha.=constant where .alpha. is of the angle between the line of reciprocating movement and a normal to the transportation direction. According to another feature, the angle may be controlled by Vt such that parallelism of the scanning lines is maintained.

Abstract: The devices for holding down a speciman to be tested are arranged on the e side of the tube as the transducer, without the tube movement being obstructed. The holding down devices may be arranged directly opposite to the rotation devices, or optionally in the immediate neighborhood thereof. Bending of the tube due to the holding devices does not occur even where relatively large pressing forces are used.