SU1404823A1 - Digital meter of vibration parameters - Google Patents

Abstract

This invention relates to a measurement technique. The aim of the invention is to improve the accuracy and enhancement of functionality by eliminating distortion caused by interference effects in the reflection of the light flux from the surface of the sensitive element in the absence of vibration, and the operation of measuring the frequency of vibration. The device comprises a light source 1, a light guide 2, a sensing element 3 and a photodetector. The sensing element 3 is made in the form of an elastic transparent film that is a multiple of an odd number of quarters of the wavelength of the light source 1, which makes it possible to compensate the reflected light flux in the absence of vibration. Vibration causes changes in the thickness of the elastic transparent film, violating the conditions for quenching the reflected light flux. As a result, a sequence of light pulses arrives at the photoreceiver input with an α-amplitude proportional to and a frequency equal to the vibration amplitude and frequency, respectively. 3 il. with fS in

Description

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The invention relates to measurement technology and can be used to measure the amplitude and frequency of vibration of machines and mechanisms.

The aim of the invention is to improve the accuracy and spread of functionality by eliminating distortions due to interference effects when reflecting the light flux from the surface of the sensing element in the absence of vibration, and the measurement operation simultaneously with the amplitude and frequency of vibration.

Figure 1 shows the structural diagram of the optical part of the device; Fig. 2 illustrates the construction of a sensing element; on fig.Z - functional scheme of the electronic part of the device

The device contains (Fig. 1) the light source G, the light guide 2, the sensitive element 3 and the photodetector, for example, in the form of a transducer 4 light pulses into pulses, for example, and the sensitive element 3 is optically connected by the light guide 2 to the light source 1 and photodetector.

The sensing element 3 contains (figo 2) a sleeve 5 of an insulating material that is glued to the light guide 2, a transparent gasket 6 fixedly mounted inside the sleeve 5 close to the end of the light guide 2, a gasket 7 with a tap installed inside the sleeve 5 and can be moved along its axis, and an elastic transparent film 8 thick, a multiple of an odd number of quarters of the wavelength of the light source 1, placed inside the sleeve 5 between the transparent gasket 6 and the gasket 7 with a tap The meter also contains an integrator 9, whose inputs are connected respectively, with the first and second outputs of the converter 4 SI, analog-digital converter (ADC) 10, the input connected to the output of the integrator 9, the expander 11 pulses, including, among other standard elements of circuitry, a timer and an electronic key (not shown) In this case, the electronic key is the input of the connection to the first code of the timer, and its output is the first, and the second is. the timer according to the second output

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A pulse expander II, an input connected to the third output of the 4-SI converter, and a 12 pulse counter, a counting input and a curbing input connected to the first and second outputs of the expander 11 pulses, respectively. The outputs of the pulse counter 12 and the ADC 10 are the outputs of the device

The device operates as follows.

In the initial state, the luminous flux from the source -1 of the light, passing through the thickness of the elastic transparent film 8, having a thickness multiple to an odd number of quarters of the wavelength of the source 1 of the light and reflected from the surface of the strip 7 with a tap, is quenched by interference transparent pads 6.

When the tap of the gasket 7 is rigidly connected to the vibrating surface, but so that the sleeve 5 remains stationary, the thickness of the elastic transparent film 8 changes, and therefore, the condition for damping the reflected light flux is violated. As a result, a sequence of light pulses having an amplitude proportional to the amplitude of vibration and the frequency equal to the frequency of vibration is fed to the input of the converter of 4 SI. SI converter 4 converts a sequence of light pulses into voltage pulses, also having an amplitude proportional to the amplitude of the vibration, and a frequency equal to the frequency of the vibration. From the first output of the converter, 4 SI sequences of electric pulses, whose amplitude is proportional to the amplitude of vibration, are fed to the input of the intergrator 9, at the output of which a constant voltage is established that is proportional to the amplitude of vibration. For ease of recording, as well as to increase the level of automation of the measurement process, this voltage is converted into a digital code by means of ADC 10.

At the same time, the sequence of voltage pulses is transformed by comparing in the converter 4 SI into voltage pulses normalized in amplitude to the required level. However d for reliably

It is necessary to increase the duration of these pulses to an optimal value. At the same time, in its first step, the timer generates a voltage pulse with a duration of 1 s, which opens the electronic key (not shown) of the expander 12 pulses. The voltage pulses, the level and duration of which are matched with the requirements for the level and duration of the circuitry elements used, arrive at the counting input of the counter 12 pulses. In the pulse counter 12, the number of pulses is counted in 1 second. A code for the number of pulses is output to the display device or processing device, which is determined by the measurement tasks. At the end of a one-second pulse, after 1 second, the expander timer 11 pulses out a pulse through the second input, which zeroes the counter of 12 pulses. Next, the measurement process is repeated. The memorization time of the pulse number code. In the counter, 12 pulses can be changed by executing the nejiecTpaHBaeMbiM timer.

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Thus, the proposed device allows to measure the frequency, amplitude of vibration, and use conventional multimode optical fiber without reducing the accuracy of measurements or other parameters.

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Claims (1)

Formula of gain A digital vibration parameter meter containing a light source, a photodetector, a light guide, and a sensing element optically coupled to the light guide with a light source and a photoreceiver, characterized in that, in order to improve accuracy and enhance functionality by measuring simultaneously with amplitude, also frequency vibration, it is equipped with an integrator, inputs connected respectively to the first and second outputs of the photodetector, analog-to-digital converter, input connected to the output 5 integrator, a pulse expander, an input connected to the third output of the photodetector, and a pulse counter, a counting input and an output of zeroing, connected respectively to the first 0 and the second outputs of the pulse extender, and the sensitive element is made in the form of an elastic transparent film with a thickness multiple to an odd number of quarters of the source wavelength; Sveta.. 0 FIG. 2