SU1138659A1 - Device for testing articles in self-excited oscillation mode - Google Patents

Abstract

A DEVICE FOR TESTING PRODUCTS IN AUTOCLEVELENT MODE, containing an output converter, an input converter and an input;. a nonlinear element connected to it, a regulated voltage source, an integrator, a voltage converter — a current, a reversing switch, one of which diagonals is connected between the output of the nonlinear element and the integrator's input, the other to the outputs of the converter voltage J-C H current, the input of which is connected to a source of adjustable voltage, which is due to the fact that, in order to automate the tests, it is supplied with a source of voltage of opposite polarity, a second reversing switch, input connected to the output of the nonlinear element, one of the diagonals of the second reversing switch through. the resistors are connected to a source of opposite polarity, a switch, a potentiometer connected to the zero potential bus, the first output to the input of the output converter, and a second output through the switch to the input of the terminal (the linear element, the first input of the potentiometer is connected to the output of the integrator , the second input through the switch - with the output, the second reversing switch from 00 O) ate with

Description

Evaluation refers to measurement technology and can be used to control quality or determine product characteristics. A device for testing products in an oscillatory mode is known, comprising an output converter, an input converter and a nonlinear input connected to it, an element, a variable voltage source, an integrator, a voltage converter — a current, a reversing switch — one of the diagonals of which is turned on between the output of the nonlinear element and the input of the integrator, and the other to the outputs of the transforming voltage, the current whose input is connected to the source of the adjustable voltage II. The disadvantage of the known device is the inability to automate the tests. The purpose of the invention is to automate product testing. The aim is to ensure that a device for testing products in a self-oscillating mode contains an output converter, an input converter, and an input associated with it a nonlinear element, a variable voltage source, an integrator, a voltage converter — a current, a reversing switch, one from the diagonals of which is connected between the output of the nonlinear element and the input of the integrator, a friend is connected to the outputs of the voltage converter — the current whose input is connected to voltage adjustable point, supplied with an “opposite voltage source, second. By means of a reversing switch, the input connected to the output of the nonlinear element, one of the diameters of the second reversing switch of the bodies is connected via resistors to an opposite source of voltage, the switch,. the potentiometer connected to the zero potential bus, the first output to the output of the output converter, the second output through a switch to the input of the nonlinear element, the first input of the potentiometer is connected to the output of the integrator, the second input through the switch to the output of the second reversing switch. 92 The drawing shows a block diagram of a device for testing products in a self-oscillating mode. The device contains output 1 input 2 converters and an input connected to the last nonlinear element 3, source 4 of adjustable voltage, integrator 5, converter 6 voltage - current, reversible bridge switch 7 one of the diagonals of which is connected between the output of the nonlinear element 3 and the input of the integrator 5, the other to the outputs of the voltage converter 6 is the current whose input is connected to the source 4 of the regulated voltage wives Source 7 voltage of opposite polarity, the second reversing send -. The input 8 is connected to the output of the nonlinear element 3, one of the diagonals of the second reversing switch 8. Through the resistors 9 and 10 is connected to the source 7 of the opposite polarity, the switch. 11, a potentiometer 12 connected to the zero potential bus (not marked), the first output to the input of the output converter 1, the second output through the switch 11 to the input of the nonlinear element 3, the p. 12 input of the potentiometer 12 connected to the output of the integrator 5, the second the input through the switch 11 is with the output of the second reversing switch 8; the device for testing the products in the self-oscillating mode works as follows. Before switching on the device, transducers 1 and 2 are connected to the product being tested, and as a result, when the switch 11 is shown in the drawing, an open-loop self-oscillating circuit of the 1,2,3,5,7,12 elements and the product under test is formed. After the device is switched on, the self-oscillating mode of the specified circuit can be called up in two ways. The first, traditional method, implemented by a known device, presupposes striking a product under investigation, after which oscillations occur in the oscillatory circuit with a frequency determined by the resonant frequency of the main device of the test product, Amplite3

The oscillations of the tested product depend both on its properties and on the magnitude of the signal from the output of the integrator 5 and the moving contact. Potentiometer 12, The amplitude of the triangular signal at the output of the integrator 5 is determined by the values of the currents flowing through the switch 8. The reversing switch 8 operates in phase with the switch of the nonlinear element 3, providing alternate connection of the input of the integrator 5 to the output converter 6, which converts the voltage from the output of the source 4 into differently directed currents of the same magnitude. Therefore, the beginning of the Test of various types of products, which are: are characterized by different values of the resonant frequencies of the fundamental tone, tune the signal at the output of the integrator 5,

This adjustment is provided by adjusting the voltage. At this certain voltage level Uv, c. corresponds to its frequency of E-oscillations in the auto-oscillating circuit of the device with a constant amplitude of oscillations at the output of the integrator 5, Adjusting the amplitude of the action applied to the test piece of the effect is carried out by moving the slider potentiometer 12,

.- The second method of driving self-oscillations in the main circuit, which is implemented in the proposed device, involves a brief switching of the switch 11 to the upper position. In this case, the main auto-oscillating circuit, including the product under test, is open, however, at the same time, an additional auto-dynamic circuit is formed from the series-connected integrator 5 and non-linear element 3, in the positive feedback circuit of which the second reversing switch 8 is turned on. The oscillations in this additional circuit are also determined by the magnitude of the voltage from the source 4 of the regulated voltage. By connecting the potentiometer 11 to the output of the integrator 5 and the output of the second reversing switch 8, the displacement of its sliders c.

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the purpose of adjusting the amplitude of the signal entering the input of the encoder 1 will not lead to a change in the frequency of oscillations in the additional circuit. The stimulating signal of a triangular shape from the output of the integrator 5 through potentiometer 12 will cause forced oscillations of the test product with a frequency

close to the resonant frequency of the fundamental tone. By switching on the second reversing switch 8, in which one diagonal through resistors 9 and 10 is connected to the source 7 of opposite polarity, to the positive feedback circuit of nonlinear element 3, the static hysteresis characteristic of the latter turns out to be symmetrical. Therefore, stimulating. The triangular waveform received in the additional loop will also be symmetric.

when the switch I1 returns to the initial position shown in the drawing, the main self-oscillating circuit containing the test product closes. Since by this I moment in the tested product, oscillations were excited by a stimulating signal,

the conditions for the existence of a self-oscillatory regime in the main circuit,

Thus, the introduction of new elements into the device allows for a short circuit of switch 11 to receive a stimulating

a signal that; "1 the test article swings. Releasing one of the contacts of the switch 11 leads to the formation of a self-oscillating circuit in which a self-oscillating mode arises, the conditions for which are created by a preliminary effect on the test product of a stimulating signal. As a result, the initial mechanical effects that ensure the conditions

the occurrence of the auto-oscillation mode. In addition, since the frequency

If the signal is stimulating, being set close to the resonant frequency of the fundamental tone, the possibility of excitation is almost eliminated.

The main advantage of the invention at the higher frequencies of the property is the implementation of automating oscillations of the subject of testing, which shortens the time of the test.

Claims (1)

DEVICE FOR TESTING PRODUCTS IN AUTO-OSCILLATING MODE, containing an output converter, an input converter and an input '%', a non-linear element connected to it, an adjustable voltage source, an integrator, a voltage-current converter, a reversing switch, one of the diagonals of which is connected between the non-linear element output and the input integrator, the other - to the outputs of the Converter voltage current, the input of which is connected to a regulated voltage source, characterized in that, in order to automate the test Nij, it is provided with a voltage source of opposite polarity, D versivnym second switch input connected to the output of the nonlinear element, one of the first diagonal of the second reversing switch through. resistors are connected to a voltage source of opposite polarity, a switch, a potentiometer connected to the zero potential bus, the first output to the input of the output converter, the second output through the switch to the input of a nonlinear element, the first input of the potentiometer connected to the integrator output, the second input through the switch with output, second reversing switch.