SU238209A1 - - Google Patents

Description

Methods are known for determining the tension force of rods, for example anchors, based on the excitation of natural oscillations in them.

The described method differs from those known in that, in order to improve the accuracy of measuring the tension force of rods, the body of which is not available for direct measurements, oscillations in the rods excite by transverse periodic pulses acting behind a hard point of support with a variable frequency and amplitude of natural oscillations. t to the resonance value, which is picked up with the help of sensitive sensors and the tension is determined from it.

FIG. 1, 2 and 3 show the devices for carrying out the described method.

The oscillations of the rod are excited by an electromagnet 1 (Fig. 1), a signal generator 2 (Fig. 2), a generator 3 of mechanical oscillations (Fig. 3), etc.

When the frequency of oscillations reported to the anchor coincides with the frequency of its natural oscillations, the amplitude of oscillations of the rod sharply increases, i.e. a resonance occurs. The moment of onset of resonance is recorded by sensor 4 (Fig. 2), cylindrical resonator 5 (Fig. 1), plate resonant device 6 (Fig. 3), etc.

The sensor, which fixes the onset of resonance, can be of any design, but it is mounted on the end of the rod together with the exciting generator. The signal from the sensor is amplified and fed to an ultrasonic meter. At the moment of deflection, the arrows Φ 1 xxcall the frequency at which resonance occurred, and according to a previously plotted schedule or on a scale, the tension of the rod tension at the given moment.

Subject invention

The method of determining the tension force of rods, for example, angroves, is based on measuring the natural vibration frequency, characterized in that, in order to increase the accuracy of measuring the tension force of rods, the body of which is not available for direct measurements in them, oscillations in the rods are excited by transverse periodic pulses, acting behind a rigid point of support, with variable frequency, and bringing the amplitude of the natural oscillations of the rods to a resonance value, which is captured using sensitive sensors, and along it limit by a tension-l senie.

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