SU1677551A1 - Arrangement for measuring narrow-band vibration process - Google Patents

Abstract

The invention relates to a vibration measuring technique and can be used to assess the technical condition of machines and mechanisms. The aim of the invention is to increase the reliability of the measurement. The device implements the formation of a signal in accordance with the expression R K a, where R is the intensity of the vibration process; K is a coefficient depending on the type of distribution density and selected in accordance with the measured value; o - rms process value.

Description

The invention relates to a vibration measuring technique, namely, devices for measuring the intensity of a narrowband vibration process and can be used to assess the technical condition of machines and mechanisms.

The aim of the invention is to increase the reliability of the measurement.

The drawing shows a block diagram of the device.

A device for measuring the intensity of a narrow-band vibration process comprises a series-connected vibration converter 1, an amplifier 2, a band-pass filter 3 and a detector 4, a unit 5 measuring the ratio of the fourth order central moment to the square of the dispersion connected by the inputs to the input and output of the detector 5. The measurement unit 5 has the first and the second channels (not indicated by separate positions in the diagram) formed by series-connected quadrants 6, 7 and 8, 9, respectively.

Measurement unit 5 also includes a divider 10 and an averager 11.

The output of the Quad 7 of the first channel is connected to the input of the divider 10 through the averager 11, and the output of the Quad 9 of the second channel is connected to the input of the divider 10 directly. The input of the first channel (input of the quadrant 6) is connected to the input of the detector 4, and the input of the second channel (input of the quadrant 8) is connected to the output of the detector 4.

The device also contains serially connected analog-to-digital converter (ADC) 12. connected to the output of measurement unit 5 (splitter output 10), memory block 13, digital-to-analog converter (DAC) 14, multiplication unit 15, to the second input of which detector 4 is connected and indicator 16.

About VI VI

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Vibration intensity estimates used in the vibro-measuring technique, based on determining only energy or only dimensionless characteristics (for example, using the RMS value of process A or the coefficient of extremity E, cannot serve as an unambiguous criterion of the technical condition of machines and mechanisms.

It is more reliable to estimate the intensity of vibration based on the detection of a connection between the indicated energy and dimensionless characteristics of the process, which is implemented in the device.

The device works as follows.

The signal from the vibrator 1, after amplifier 2, is fed to the input of bandpass filter 3, which selects the required frequency range. The signal is then fed to the input of the detector 4, the output of which forms a signal equal to the mean square value and to the input of the quadrant 6. Then the signal passed through the quadrant 7 and the averager 11 is fed to one of the inputs of the divider 10. The signal from the output of the detector A enters the input of the Quad 8 (second channel of the measurement unit 5), and then through the quad 9 - to the other input of the divider 10. The signal from the output of the divider 10, equal to the measured value Mi (Mi E + 3), flows through the ADC 12 to the block 13 of the memory ti.

In memory block 13, according to a specific program, a correspondence is established between each measured value M and coefficient K, where K is a coefficient depending on the type of process distribution density (the entire set of possible values of K is determined in advance and previously recorded in memory block 13). Block exit code

13 memory through the DAC 14 is fed to the input of the multiplier 15, the second input of which receives a signal equal to the root-mean-square value. At the output of the multiplier 15, a signal is formed in accordance with the expression R K -a, where R is the intensity of the vibration process in a given frequency range. The measured intensity of the vibrating process is displayed in the indicator 16.

Claims (1)

Apparatus of the Invention A device for measuring the intensity of a narrowband vibratory process, comprising connected vibration transducer, amplifier, band-pass filter and detector, unit for measuring the ratio of the central moment of the fourth order to the square of the dispersion, the indicator characterized by that, in order to increase the reliability of the measurement, it is equipped with a series-connected analog-to-digital converter, a memory unit, a digital-to-analog converter and a multiplier, the second input of which is connected to the detector output, to the input and output of which the first and second inputs of the measuring unit are connected, respectively, the output of the measuring unit is connected to the input of the analog-digital converter, and the indicator input is connected to the multiplier output.