SU1337760A1 - Device for acoustic-emission check of defects - Google Patents

Abstract

The invention relates to the field of non-destructive testing of materials and products by acoustic emission signals (AE). The aim of the invention is to increase the reliability of control by taking into account the time intervals between extremes, the current value of the AE signal in the absence of non-local extremes, and also the sorting and accumulation of information according to a given attribute of its belonging. An adaptation of the specified value is automatically performed, with which the modulus of the difference between the values of the current and previous non-local extremes is compared in block 16 for determining the non-local extremum. The obtained information on the parameters of extrema is accumulated taking into account its belonging to this or that process, for example, signals at the loading and unloading phase are analyzed. For this electronic computer (computer) 13 to the channel, the Control issues a switch code of switch 30, k (L f2

Description

after decryption in the decoder 14, the control commands generates a control signal through the third circuit OR 22 to the input of the trigger 23, which switches the switch 30. Memory block 12 in the control device

The invention relates to non-destructive testing of materials and products by acoustic emission signals (AE) and can be used to diagnose the technical state of the test object.

The purpose of the invention is to increase the reliability of control due to the presence of blocks, which allow to take into account the time intervals between extremes, the current value of the LE signal in the absence of non-local extremes, which provide the possibility of eliminating the accumulation of information about local extrema, as well as sorting and accumulating information according to a given sign of its belonging .

The drawing shows a device for acoustic emission defect control,

The device for acoustic emission monitoring of defects contains a series-connected receiving transducer 1, a signal amplification and selection unit 2, a detection unit 3, an analog-to-digital converter (ADC) 4 and an extremum detection unit 5, B (filled in the form of serially connected register 6 the current count, the previous count register 7, and the first comparison circuit 8, the output of the current count register 6 is connected to the second input of the first comparison circuit 8, a series-connected pulse generator 9 and a counter 10, the extremum time parameter block 11, the memory block 12, the computer (computer) 13, the decoder 14 control commands, the input of which is connected to the output of the computer control 13, and its first output is connected to the input of the external control

The role of defects implements the principle of parallelization of information, which is used to reconcile a high rate of receipt of information with a limited speed of entering information into a computer. 1 il.

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No memory block 12, the extremum time control terminal is connected to the control code of the extremum determination unit 5, informational 1, the memory input of the memory unit 12 is connected to the information output of the extremum determination unit 5, and the first output is connected to the input of a computer 13 , the first scheme OR 15, the non-local extremum determination unit 16, containing the extremum register 17 connected in series, the difference modulus determining unit 18 and the second comparison circuit 19, a set value register 20, the output of which is connected to the second input of the second The comparison circuit 19, the first input of the extremum register 17 is connected to the second input of the spacing module 18, and the third output of the extremum detection block 5, the input of the register 20 of a given value is connected to the output of the computer 13, the output of the second comparison circuit 19 is connected to the first input the first OR 15 circuit, the second input of which is connected to the transfer output of the counter 10, the output of the first OR circuit 15 is connected to the input of the register 17 of the extrema and to the control input of the reset of the counter 10, the memory unit 12 contains the second connected in series 21, the third 22 OR circuits and the trigger 23 connected in series the first counter 24

35 addresses and a first memory circuit 25 connected in series a second address counter 26 and a second memory circuit 27, a first memory circuit 25 and a first address counter 24, and

 O second circuit 27 memory and second

the counter 26 addresses form, respectively, the first 28 and second 29 storage units, the switch 30, s

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the formation input of which is connected to the second output of the counter 10 and to the information output of the extremum determination unit 5, the write control input of the switch 30 is connected to the output of the OR 15 circuit, the pair outputs of the switch 30 are connected to the corresponding inputs of the memory 25 and 27 outputs of the first 25 and second 27 memory circuits and the first 24 and second 26 address counters are connected to the input of the computer 13, the transfer outputs of the first 24 and second 26 address counters are connected to the inputs of the second OR circuit 21, the output of which is connected to the input Interrupt of the computer 13, second third second OR circuit 22 is connected to the second output of the decoder 14 control commands, output latch 23 is connected to a control input of the switch 30, the first and second inputs of first 25 and second 27 memory circuits connected to the respective inputs of the first 24 and second counter 26 addresses.

The device for acoustic emission defect monitoring works as follows.

The AE signal is received by the receiving transducer, fed to the amplification and selection unit, the detecting unit 37 and converted into a digital code in the A / D converter 4, from the output of which, as a sequence of digital kodos, goes to the extremum determination unit 5. In block 5, the change in the sign of the difference between two consecutive samples of ADC 4, which are recorded in registers 6 and 7 of the current and previous counts, is analyzed using the first comparison circuit 8. The presence of a difference sign indicates the existence of an extremum, at the output of the first comparison circuit 8, a control signal is formed in memory block 12, according to which the current count of the counter 10 of the block 1I for determining the extremum time parameters is recorded in the first memory circuit 25 of the first memory block 28. From the output of the extremum determination unit 5, the code of the preceding readout of the A / D converter 4 enters the non-local extremum determination unit 16, where with the help of the difference modulus determination unit 18 and the second comparison circuit 19 the condition of exceeding the specified value by the absolute difference between the values of the current

extremum and previous non-local extremum, which are stored respectively in registers 20, 7 and 17. If the condition is satisfied, which indicates that the extremum is non-local, then from the output of the second comparison circuit 19 through the first OR circuit 15 to the input control of the extremum register 17 receives a signal that rewrites the current extremum from register 7 to the non-local extremum register 17. In the process of further

5, the operation of the device already a new value of the non-local extremum is compared with the subsequent extremums, which are highlighted in block 5 of the extremum determination. At the time of determining a local extremum, the signal coming from the output of the first circuit OR 15 is simultaneously applied to the recording control input of the extremum value of the memory block 12. Under the influence of this

5 of the signal to the first memory circuit 25 of the first storage unit 28, the current sample code of the nonlocal extremum is written and the unit is added to the first counter 24 of the server by preparing the address of the memory cells of the first memory circuit 25 to record the subsequent information.

If the parameters of the AE signal are such; oops that the AE pulses are rarely characteristic or the extremes selected do not meet the criterion of a nonlocal extremum, then in case of overflow of the counter 10 in block 11 of determining the extremum time parameters, i.e. in the absence of a non-local IIKCT-remum in a fixed measurement time interval, a control signal is fed from the transfer output of the counter 10 through the first OR 15 circuit to the control input of the extremum register 17 and to the control input of the extremum value of the memory block 12. Under the action of this signal, the information in the extremum register 17 is updated, and the information about the current value of the AE signal and its time is entered into the memory of the second storage unit 29. In this case, a sign that the countdown is not a nonlocal extremum will correspond to the most significant bit of the time code to state 1, which occurs when the counter overflows 10. Therefore, upon further analysis of the information

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programmatically using a computer 13, nonlocal extremes easily differ from current values.

After the current value or nonlocal extremum of signals from the output of the first OR 15 circuit is recorded into the second storage unit 29, the counter 10 is also reset, after which the new time interval begins to read the next nonlocal extremum or the current value of the AE signal.

The process of accumulating information in the second storage unit 29 is limited to the final memory size of the second memory circuit 27. When filling the entire volume at the output of the transfer of the second counter 26 of the address, a signal is generated, coming through the second circuit 20 or 21 to the bus Interrupting the computer 13 and through the third circuit OR 22 to the trigger input 23. The latter switches the switch 30 in such a way that the accumulation of information will be made in the first storage unit 28, and the second storage unit 29 will be brought into the information readout mode, which is reported by the signal sent to the computer 13 interrupt bus. When reading information from the second ominayuschego unit 29 supplies the computer 13 commands the decoder 14, a control signal corresponding to the code information read, after which deoshfra- tion sets the address of the second counter 26 outputs the address and connects the second memory circuit 27 to the channel input computer. After entering the information in the computer 13, the data is subjected to further processing by the program in accordance with the accepted algorithm. Based on the results of this processing, the device allows you to automatically adapt the specified value, with which the absolute value of the difference between the current and previous nonlocal extrema values is compared. block 16 of determining a non-local 50 extremum. At the same time, the computer 13 via the Vyogod channel writes into the register 20 of a given value the optimal value of a given value in the sense of being accepted by it to one or another process or event. For example, in case of fatigue testing of an object, it is required to analyze the signals separately during the loading and unloading phase. To do this, at the required time of the computer 13 into the channel, the Control issues a switch code, the switch 30, which, after decoding the control commands in the decoder 14, generates a control signal received through the third circuit OR 22 to the input of the trigger 23, which switches the switch 30. When reading information In this mode of operation, the device for checking the defects of the computer 13 first accesses the Input channel to the counter 24 or 26 of the address of the storage units 28 and 29 that is provided by the computer 13 for reading information. The state of the counter 24 or 26 corresponds to the volume of accumulated information in the previous measurement cycle. This amount of information must also be entered from memory block 12 into computer 13. Memory block 12 also allows the principle of parallelizing information to be used, which are used to match a high information arrival rate with a limited information input speed in a computer.

Thus, the proposed device allows to increase the reliability of control by introducing blocks that automatically take into account the properties of signals and control the value specified to isolate nonlocal extremes, with a prolonged absence of AE pulses, to estimate the current AE signal in the interpulse interval, to accumulate information, taking into account the sign of its belonging, and the type of accumulated information provides an opportunity to rebuild the algorithms of its processing with a considerable degree of freedom.

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Claims (1)

Apparatus of the Invention A device for acoustic emission defect monitoring, comprising a series-connected receiving transducer, a signal amplification and selection unit, a detectable quality criterion unit for operation, 55 and an analog-to-digital converter no defect control device. The device allows you to accumulate the received information about the parameters of extrema taking into account the accessories ten 15 20 50 37760 its to a particular process event. For example, in case of fatigue testing of an object, it is required to analyze the signals separately during the loading and unloading phase. To do this, at the required time of the computer 13 into the channel, the Control issues a switch code, the switch 30, which, after decoding the control commands in the decoder 14, generates a control signal received through the third circuit OR 22 to the input of the trigger 23, which switches the switch 30. When reading information In this mode of operation, the device for checking the defects of the computer 13 first accesses the Input channel to the counter 24 or 26 of the address of the storage units 28 and 29 that is provided by the computer 13 for reading information. The state of the counter 24 or 26 corresponds to the volume of accumulated information in the previous measurement cycle. This amount of information must also be entered from memory block 12 into computer 13. Memory block 12 also allows the principle of parallelizing information to be used, which are used to match a high information arrival rate with a limited information input speed in a computer. Thus, the proposed device allows to increase the reliability of control by introducing blocks that automatically take into account the properties of signals and control the value specified to isolate nonlocal extremes, with a prolonged absence of AE pulses, to estimate the current AE signal in the interpulse interval, to accumulate information, taking into account the sign of its belonging, and the type of accumulated information provides an opportunity to rebuild the algorithms of its processing with a considerable degree of freedom. thirty 35 40 45 Apparatus of the Invention A device for acoustic emission defect monitoring, comprising a series-connected receiving transducer, a signal amplification and selection unit, a detecting unit for determining the extremum, a sequentially connected pulse generator and a counter, a memory unit, an electronic computer, a decryption unit .1337760 control, the input of which is the control of the electrolysis machine, and its g is connected to the input of the external memory block, the input is recorded in time by an extremus connected to the control of determining the extremum of the controller and not w with those in the class ma, the information input of the memory block is connected to the information output of the extremum determination block, and the first output is connected to the input of an electronic computer, characterized in that, in order to increase the reliability, it is equipped with the first OR circuit, a block for determining a nonlocal extremum containing connected successively the extremum register, the module for determining the difference modulus and the comparison circuit, a register of a given value, the output of which is connected to the second input of the comparison circuit, a new input of the extremum register is connected to th input block difference determination module and to a third output unit for determining an extremum setpoint register input coupled to you Vysod is connected with the second output of the decrypting machine, the output of the control command comparison circuit, and the output connected to the first input of the first OR circuit, the second input of which is connected to the switchgear. Managing Director E.Kopcha Order 4123/41 Compiled by I. Ardasheva Tehred I. Popovich Corrector Circulation 776 Subscription VNIIPI USSR State Committee for Inventions and Discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, Projecto st., 4 eight the output of the first OR circuit is connected to the control input of the extremum register and the counter reset input of the counter, the memory unit contains a second, third OR circuit and a trigger connected in series, the first address counter and the first memory circuit connected in series successively the second address counter and the second memory circuit, the switch, the information input of which is connected to the second output of the counter and the information output of the extremum determination unit, the control input entry the switch is connected to the output of the first OR circuit, the switch paired outputs are connected to the corresponding inputs of the memory circuits, the outputs of the first and second memory circuits and the first and second address counters are connected to the input of the electronic computer, the transfer outputs of the first and second address counters are connected to the inputs of the second OR circuit, the output of which is connected to the input of the Interruption of the electronic computer, the second input of the third circuit 0 five OR is connected to the second output of the control decoder, and the output The trigger is connected to the switch house. managing director vkorrektor V. 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