SU785758A1 - Apparatus for quality control of articles by acoustic emission method - Google Patents

Description

key 4 and the main intensity meter 5, a pulse counter 6, a voltage source 7, a comparator 8, the output of which is connected to the second input of the first electronic key 4, an additional intensity meter 9 connected between the pulse ICOB shaper 3 and the comparator 8, In addition, the device contains serially connected second electronic key 10, the first input of which is connected to the output of the source 7, and the second input to the output of the comparator 8, the adder 11, the second input of which is connected to the output of the main intensity meter 5 and the first recorder 12. The first the input of the third electronic key 13 is connected to the output of the comparator 8, and the second input to the output of the imaging unit 3. The impulse counter b is reversible, the subtracting input is connected to the output of the key 13, and the summing - to the output of the first electronic key 4.

The device works in the following way.

From the output of the electroacoustic transducer 1, electrical acoustic emission signals and noise signals are fed to the input of amplifier 2, where the current filtering from the vibration signals of machines and mechanisms is amplified and passed for hours and 3 pulses are fed to the driver, where the amplitude of them forms the signals necessary for the normal operation of the intensity meters to the counter. These signals are fed to the inputs of the Additional Intensometer 9 and the electronic keys 4 and 13. In the initial state, the keys

4 and 10 are closed, and the key 13 is open. Next, the signals are sent to the subtracting input of the reversible counter of 6 pulses. When the voltage at the output of the additional intensity meter

9 exceeds the threshold level taken as the noise level and set by the reference voltage source 7, the comparator 8 is triggered, the keys 4 and 10 are opened, and the key 13 is closed. Signals are fed to the input of the main intensity meter

5 and the summing input of the reversing counter b.

The summing input of the adder 11 from the output of the main intensity meter 5 receives a voltage proportional to the intensity of the flow of useful signals and interference signals:

U + - K;, (Nt + Mn), where K. is the conversion factor

main intensimeter; MD is the intensity of the flow of useful signals;

M is the intensity of the flow of interference signals,

and the voltage from the source of reference voltage to the subtracting input through the key 10, where j is some

a scale factor, the value of which depends on the conversion factors of the main Q and Q, additional intensimeters. Wherein

Unop- i n The output of the adder 11 is equal to:

g (., -,,

i.e. equal to the intensity of the flow of useful signals.

From the output of the adder, signals are received for registration in the recorder 12.

To the summing input of the reversible counter of 6 pulses, the controlled electronic key 4 also receives a mixture of the useful signal and interference signals, and the subtracting signal — via the controlled electronic key 13. Consequently, the indications of the intensity meter and the pulse counter are directly proportional to the intensity of the flow of useful signals and their total number.

The proposed device allows to increase the reliability of the control.

Claims (2)

1. A device for controlling the quality of products by acoustic emission, containing a series-connected electroacoustic transducer, amplifier, pulse shaper, first key and main intensity meter, pulse counter, reference voltage source and comparator, whose output is connected to 5 with the second input of the electronic key, an additional intensity meter connected between the pulse shaper and the comparator, characterized in that, in order to increase the reliability of the control, it is equipped with serially connected with a second electronic key, the first input of which is connected to the output of the reference voltage source, and the second input - to the comparator output, an adder, the second input of which is connected to the output of the main intensity meter, a register and a third electronic key, the first input of which is connected to the output of the computer Ator, the second input - to the output of the pulse shaper. 2. The device according to claim 1, characterized in that, in order to increase accuracy, the pulse counter is reversible, its input is connected to the output of the third electronic key, and the summations to the output of the first electronic key. Sources of information taken into account in the examination 1.Greshnikov V, D., Drobot Yu. B. Acoustic emission. M., Publ. standards, 1976, p. 67. 2. Authors certificate of the USSR 534687, cl. G 01 N 29/04, 1975 (prototype).