SU1040407A1 - Ultrasonic pulse signal amplitude measuring device - Google Patents

Abstract

CURRENT DEVICE FOR MEASURING EMPZSHTUDA ULTRASONIC PULSE SIGNALS Some of the devices contained in the series are connected to an electroacoustic transducer, an amplifier, a comparator, a pulse counter and a digital-analogue transducer, a series of co-amplitude amplitude detector and a line. - with the comparator, and the registrar, ..., except that, in order to increase the resolution, it is equipped with a filter that is connected between Amplifier and comparator, trigger and switch, the output of which is connected to the recorder input, the input - with the output of the pulse counter, the trigger input is connected to the output of the amplitude detector, the second trigger input - with the output of the delay line,. ; and the trigger output is connected to the input of the 1 delay line and the second inputs of the filter and switch, and the output of the digital-to-analog converter is connected to a common input of the comparator. (L

Description

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4: About

This invention relates to Hepaspyiaalomej y quality control of products using ultrasonic pulse signals.

The closest to the present invention is a device for measuring the amplitude of ultrasonic pulse signals, comprising a series-connected electroacoustic transducer, amplifier, comparator, pulse counter and digital-analog converter, a series-connected amplitude detector and a delay line, the output of which is connected to the second pulse counter input, and the input the bulk detector - with the output of the comparator, and the recorder Cl.

A disadvantage of the known device is the low resolution in the case when the duration of the measured ultrasonic pulse signals is comparable with the time intervals between them.

The purpose of the invention is to increase the resolution.

The goal is achieved by the device for measuring the amplitude of ultrasonic pulse signals containing series-connected transducer, amplifier, comparator, pulse counter and digital-analog converter series-connected amplitude detector and a delay line, the output of which is connected to the second input of the pulse counter, and the input amplitude detector - with the output of the comparator, and the recorder, equipped with a filter connected between the amplifier and the comparator, the trigger and to a switch whose output is connected to the recorder input, an input to the pulse counter output, a trigger input connected to the amplitude detector output, a second trigger input to the output of the delay line, and a trigger output to the input of the delay line and the second filter and switch inputs, and run A digital-to-analog converter is connected to the second input of the comparator.

Figure 1 presents the block diagram of the device, figure 2 - timing charts of the device.

The device contains a series-connected electroacoustic transducer 1, an amplifier 2, a Q-controlled filter 3c, a comparator 4, a pulse counter 5, a switch b and a recorder 7, an amplitude detector 8 connected in series, a trigger 9 and a delay line 10, and a digital-to-analog converter 11. Output the comparator 4 is connected to the input of the amplitude detector 8, the output of the backward line; the holders are connected to the second inputs of trigger 9 and counter 5, the output of trigger 9 to the second

(control; inputs of switch b and filter 3, the output of counter 5 is connected to the input of a digital-to-analog converter 11, and the output of the latter to the second input of comparator 4.

The proposed device works as follows.

The ultrasonic pulse signals are received by a wide-band electroacoustic transducer 1, they are converted into electrical signals (diagram a in Fig. 2), which are further amplified by an amplifier 2. The amplified signals are sent to a resonant filter 3 with a fixed quality factor, and not damped. The signal at its output is an exponentially damped sinusoidal oscillation with the resonant frequency of the filter and the damping factor, which determines the junction by the quality factor of the resonant system. Comparator 4. converts resonant oscillations (Fig. 2b) into a series of pulses shown in Fig. 26, the number of which depends on the amplitude of the input signal and the threshold of operation of the comparator. Initially, the threshold of the comparator is triggered (U), based on the assumed dynamic range of the measured signals. The number of pulses at the output of comparator 4 is counted by 5 pulses. In this case, the counter 5 through the digital-to-analog converter 11 increases the response threshold of the comparator 4 in proportion to the number of pulses read, thereby increasing the resolution of the device in the case when the duration of the ultrasonic pulse signals is comparable with the time intervals between them. Beginning with a certain number N of pulses, the counting stops, since the comparator threshold exceeds the amplitude value of the resonant oscillations of the filter, which, at the end of the input signal, decreases exponentially. This is detected by the amplitude detector 8 as the end of a series of pulses (fig.2g, which triggers trigger 9. The signal of the latter, shown in fig.2d, allows information output from counter 5 to recorder 7, performed by switch b, and simultaneously damps resonant filter 3. Damping leads to a quick release of the remaining part of the stored energy of the measured signal. The damping time, as well as the output time of the measurement result to the recorder, is determined by the delay time of the line 10 back The amplitude of the input signal (s) is related to the measured values as follows: n (-.the voltage of one stage / generated by the digital-to-analog converter; Pd - filter resonant frequency - filter time constant j 1 - coefficient of proportionality. The value of T is related to the initial quality factor I of the filter 3. The invention allows measuring the TB amplitude of closely spaced pulses without reducing the dynamic range of the measured amplitudes.

Claims (1)

DEVICE FOR MEASUREMENT The amplitude of the ULTRASONIC PULSE SIGNALS, containing a series-connected electro-acoustic transducer, amplifier, comparator, pulse counter and digital-to-analog converter, series-connected amplitude detector and delay line, the output of which is connected to the second input of the pulse counter, and the input of the amplitude detector, the input of the amplitude detector and the registrar, t _r a n e and h ayusche I with that., in order to increase the resolution, it is provided with a filter connected between Wuxi rer and a comparator, a trigger and a switch, whose output is connected to the input of recorder, input - with the output of the pulse counter, a trigger input connected to the output of the amplitude detector, the second flip-flop input - with the output of the delay line. ; and the trigger output is with the input of the delay line 1 and the second inputs of the filter and the switch, and the output of the digital-to-analog converter is connected to 'second-§ ----------------------- - _{} The} input of the comparator. (AND)' 1046407