The equipment "Zvuk"
Principle of action, the basic types and characteristics of devices
The equipment such as "Zvuk" realizes the acoustic method of natural vibrations based on measurement of frequencies of natural oscillation frequencies (NOF) of products. The equipment includes the devices based both on a method of free vibrations ("Zvuk - 203Ì"), and on a method of forced vibrations - resonant method ("Zvuk - 110Ì", "Zvuk - 130"), and also the software required for calculation of elastic constants and the analysis of NOF spectrum in the course of testing. In devices it is foreseen to receive final result of measuring in the following forms: NOF (f), sound velocity (Cl), Young’s modulus (E), sound indexes (SI) - gradation of sound velocity Cl with increment of 200 m/s, hardness of abrasive tools. It is possible as well to receive other physicomechanical characteristics of products when introducing appropriate correlation dependences.
Device "Zvuk - 203Ì" realizing the patent of Russia ¹ 2151385 has frequency range of 22 Hz up to 17,4 kHz, that allows to test products with the sizes approximately from 20 - 50 mm up to several meters. Vibrations of product are excited by mechanical impact and are accepted built - in in the case of the device by a microphone. After transformation of a signal measurement of natural frequency of product and calculation of velocity Cl, Young’s modulus E or other physicomechanical properties are carried out.
Device "Zvuk - 110Ì" and its last updating - device "Zvuk - 130" with frequency range from 0,5 up to 500 kHz are intended for testing of small-sized products approximately from 3 mm and more. Device "Zvuk – 130" allows to test also abrasive cutting wheels of any diameter. The product to be tested is fixed in the measuring rack between two piezoelectric gauges supplied with dome-shaped nozzles for reduction of influence of recieving-emiting system on vibrations of product (the patent of Germany ¹1648770, the patent the USA ¹3499318). The electronic part of the device including the generator of variable frequency and the broadband amplifier, is designed as the separate block or the printed-circuit-board inserted in IBM- compatible computer (in device "Zvuk - 110Ì"). Special software operates the work of devices. This software makes calculation of NOF expected spectrum of the tested product and choice of measuring conditions for the definite standard sizes of products of various forms and sizes. Results of testing are displayed the monitor in a graphic and digital kind.