SU1200258A2 - Automatic system for controlling stiffness of elastic element of damper - Google Patents

Abstract

1. AUTOMATIC CONTROL SYSTEM OF THE RIGIDITY OF THE ELASTIC ELEMENT OF AN ADJUSTMENT SUPPORTING BY AUTH. No. 1072012, characterized in that, in order to increase the noise-tolerance and tuning accuracy, two selective filters and two frequency tuning blocks are introduced, the input of the first selective filter connected to the output of the first vibration sensor signal, and the output to the first input of the first vibration the adder, the input of the second selective filter is connected to the output of the signal amplifier of the second vibration sensor, and the output is connected to the second input of the first adder, the input of the frequency detector and the first input of the phase detector, the input of each selector Nogo filter coupled to the first input of the i corresponding frequency adjustment unit, the output - to a second input (A corresponding frequency adjustment unit, a controllable input is coupled to the output of the respective frequency tuner / K.) 1C SP 00

Description

2. The system according to claim 1, characterized in that the frequency tuning unit of a selective filter comprises a serially connected frequency detector and a first lower frequency filter, as well as serially connected phase detector, a second lower frequency filter, an adder and a control element, the output of which is connected to the controlled input of the selective filter, while the first input of the block with the tuning frequency is connected to the input of the frequency detector and the first input of the phase detector, the second input of which is connected to the second input b eye .chastotnoy settings, and output nizhney.chastoty first filter coupled to the second input of the adder.

3. The system according to claim 2, wherein, in order to ensure the linearity of the adjustment characteristic of the selective filter, an optoelectronic pair is used as a control element, containing a radiation source and a photoresistor, the radiation source being connected to the output of the adder of the frequency tuning unit, and the photoresistor is part of the selective filter

The invention relates to a vibration quenching technique and is intended primarily for installation on vibroactive equipment, whose amplitude and frequency of oscillations vary iBO time, and t; for sorted instruments and. Us g1 oystvoy5; located in the area of vibroactive equipment I; -. .

The purpose of the image | Teiji is to increase the noise resistance of the system, the system of its configuration, and to ensure the linearity of the adjusting characteristic of the selective filter,.

Figure 1 shows a block diagram of the automatic control of the stiffness of the vibration damper; Fig. 2 is a schematic diagram of one of the embodiments of the selective filter. .

The system (Fig. 1) includes a vibration protection object 1, on which the - absorber 2 oscillations are installed.

The first 3 and second 4 vibration sensors, which are connected respectively to the amplifiers 5 and 6 of the vibration sensor signals, are fixed on object 1 of the vibration protection and damper 2 of the vibrations. The outputs of the amplifiers are connected respectively to the inputs of the first 7 and second 8 selective filters and the first inputs of the corresponding frequency tuning blocks 9 and 10, the outputs of which are connected to controlled inputs

corresponding selective filters 7 and 8. The output of the first filter 7 is connected to the second input of block 9 and the first non-inverting input of the first adder 11. The output of the second filter 8 is connected to the second input of block 10, the second inverting input of the first adder 11, the first input of the phase detector 12 and input frequency detector 13. In the first code adder 11 is connected to the second input of the phase detector 12, the output of which through the filter 14 of the lower frequency is connected to the first non-inverting input of the second adder 15. The output of the frequency detector 13 cut the low-pass filter 16 is connected to the second non-inverting input of the second adder 15, the output of which is connected to an absorber 2 through a DC amplifier 17,

The first input of block 9 of frequency tuning is connected to the input of frequency

detector 18 and the first input of the phase detector 19, the second input of which is connected to the second input of block 9. The output of the phase detector 19 through the first filter 20 of the lower frequency is connected to the right input of the adder 21. The output of the frequency detector 18 through the second filter 22 of the lower frequency is connected to the second the input of the adder 21, the output of which through the control element 23 is connected with the removal of the block 9, the block 10 is made similarly. The system works as follows. The maximum dynamic quenching effect is achieved. with the equality of the partial frequency of the damper oscillations of the research institute and the frequency of the exciting force. In this case, the phase shift of oscillations of object 1 of protection and extinguisher 2 of oscillations. Information should be - - oscillations about vibrations of object 1 of protection and extinguisher 2 oscillations, obtained with the help of sensors, 3 and 4 vibrations, are fed to amplifiers 5 and 6 of signals of corresponding sensors matching sensors with elements, circuits, and then through selective filters 7 and 8 to the inputs of phase 12 and frequency 13 detectors, the signal from the output of the selective filter 8 being fed to the input of the frequency detector 13 and to the first input of the phase detector 12, second the input of which is supplied from the accumulator 11 is the difference of the signals at the output of the selective filters 7 and 8. In the case of tuning conditions, i.e., in static mode, the voltage at the output of the phase detector 12 is equal to. At the output of the frequency detector 13 a signal is generated object 1, proportional to the oscillation frequency. The received signal passes through the low-pass filter 16, where its high-frequency components are smoothed, through the adder 15, through the DC amplifier 17 and fed to the windings of the extinguisher 2 oscillations. The current in the windings, proportional to the voltage at the output of the DC amplifier 17, maintains a constant value of electromagnetic rigidity and the setting frequency of the damper 2 oscillations. In the static mode, the selective filters 7 and 8 with blocks 9 and 10 of the frequency setting, respectively, work in the following way. The signal from the amplifier 5 output of the vibration sensor 3 is fed to the input of the filter 7 and the first input of block 9, the signal from the output of the filter 7 is fed to the second input of block 9. The frequency tuning block is made according to the combined principle - the tuning was performed by the frequency of the input signal and by the phase difference at the input and output of the filter, which, when fine tuned, is generally a multiple of 1. The frequency signal containing the frequency detector 18 and the low frequency filter 22 generates a signal proportional to the frequency of the input signal. A phase channel comprising a phase detector 19 and a low-pass filter 20 produces a signal proportional to the difference. phases at the input and output of the selective filter 7. The received signals are summed at the analog adder 21 and fed to the control element 23. In the static mode, the signal of the frequency channel has a constant value, and the signal of the phase control is equal to 0 the filter (e.g.; the resistance of the photoresistor) is kept constant. Thus, the selective filter 7 is tuned to the frequency of the input signal and passes it without change. In case of violation of the settings, the phase shift of the oscillations of the object 1 and the quencher 2 is different from -g, trail-. The signal at the output of the phase detector 12 is different from 0 “. This voltage leads to a change in the signal at the output of the low frequency filter 14 and the voltage at the output of the amplifier 17. At a significant detuning, changing the oscillation frequency of the object causes a change in the signal level of the frequency channel (frequency detector 13 and sixteen). This signal, day after day, with the signal of the phase channel on the analog adder 15, causes a voltage change at the output of the amplifier 17. At the same time, the current in the windings of the damper 2 oscillations changes, the electromagnetic rigidity changes and the tuning frequency. The change in frequency setting occurs until the phase shift of the oscillations of the object 1 and the vibration damper 2 becomes equal to J 3 the voltage at the output of the phase detector 12-0. At the same time, the voltage at the output of the frequency channel is set at a new level corresponding to the new value of the oscillation frequency of the object 1. In this mode, the selective filters 7 and 8 work as follows. When changing the frequency of the output signal

amplifier 5, i.e. In the dynamic mode, the voltage at the output of the frequency channel (frequency detector 18, filter 22 of frequency tuning unit 9) varies accordingly. At the output of the phase channel (phase detector 19, filter 20), a voltage different from 0 appears. This is This is due to the fact that when the input signal frequency changes, the phase difference between the input and output of the selective filter 7, which is tuned to the previous frequency, also changes.The voltages of both channels are summed up on the analog adder 21 and fed to the input of the control element 23. In this case, the filter parameter is changed until those nops until the natural frequency of the filter becomes equal to the new frequency of the input signal. With a further change in the frequency of the input signal, the selective filter 7 continues to work in the next mode. The selective filter 8 with the frequency tuning unit 10 works similarly At a constant frequency of the input signal, the selective filters are shifted to a static mode, and the automatic control system — the stiffness of the damper elastic element operates similarly to the specified one.

If there is interference in the signal from the vibration sensors (for example, higher harmonic components), the selective filter passes without changing the main signal of the frequency to which it is tuned and ensures that the rest of the spectrum components are canceled. When the frequency of the main signal changes, the selective filter monitors its evolution, while still attenuating the remaining frequencies. The parameters of the frequency tuning unit are selected so that the selective filter tracks slow changes in the frequency of the main signal and, if possible, keeps track of the relatively fast changes in the resulting input oscillation due to the action of noise.

TaKHivt, the presence in the system of a selective filter with a frequency tuning unit ensures the selection of the main signal from the noise and the normal operation of the automatic system & control stiffness of the elastic element vibration damper

both in the presence of noise, and in its absence.

In order to ensure the linearity of the adjustment characteristic of the selective filter, for example, an optoelectronic pair can be used as a control element. It contains a radiation source and a photoresistor included in the filter. The radiation source is connected to the output of the adder of the frequency tuning unit. When the frequency of the signal at the input of the filter changes, for example, when it is increased, the voltage level at the output of the adder 21 of block 9 increases. This causes an increase in the intensity of the radiation source of the optoelectronic pair, which leads to a decrease in the resistance value of the photoresistor. The resonant frequency of the selective filter varies inversely with the change in the resistance of the photoresistor included in its composition. This change occurs until the new value of the resonant frequency of the filter becomes equal to the new value of the frequency of the input signal.

In the diagram (FIG. 2), there are double optoelectronic pairs 24 and 25, a transistor 26, resistors 27–42, capacitors 42 and 43, operational amplifiers 44–48. In this case, input 1 is signal, input 2 controls phase channel, input 3 - controlling the frequency channel.

An optoelectronic pair was used as a control element in the filter. The linearity of the adjustment characteristic is ensured for the following reason. Expression, dl. the natural frequency of the selective filter is f 1 / 2FRC, where R is the resistance of the optocoupler; С - capacitor capacitance. To maintain the resonance mode, the natural frequency of the filter f must coincide with the fundamental frequency of the input signal f. Hence, when the input frequency changes, the resistance of the optocoupler must change according to the law R 1/2 TfC, i.e. inversely proportional to frequency. The characteristics of the detectors, frequency and phase, are linear. The dependence of the resistance of the optocoupler on the applied voltage R F (U) is also inversely proportional. Thus, to obtain a linear adjustment characteristic of the filter, it is only necessary to choose constant coefficients in the characteristics R F (f) and R - F (U). The use of any other control element (for example, with a linear characteristic R F (U)) cannot ensure the linearity of the adjustment characteristic in the operating range and the satisfactory accuracy of the filter setting. The presence in the automatic stiffness control system of elastic el, e5 10 15

g /

Ifut 2 vibration damping elements of selective filters with frequency tuning units increase the tuning accuracy and improve the noise immunity of the system. This increases the effectiveness of the vibration protection of the mechanisms and thereby increases their overall service life, reduces the probability of failure. Vibration dampers with the proposed automatic stiffness control system of an elastic element can be used on any systems and mechanisms, the vibration level of which exceeds the allowable, in various fields of technology.

Claims (3)

1. AUTOMATIC SYSTEM OF MANAGEMENT OF RIGIDITY OF AN ELASTIC ELEMENT OF ANSWERER OF VIBRATIONS according to ed. No. 1072012, characterized in that, in order to increase the noise immunity and tuning accuracy, two selective filters and two frequency tuning blocks are introduced into it, the input of the first selective filter being connected to the output of the signal amplifier of the first vibration sensor, and the output to the first input the first adder, the input of the second selective filter is connected to the output of the signal amplifier of the second vibration sensor, and the output is connected to the second input of the first adder, the input of the frequency detector and the first input of the phase detector, the input of each selective The filter is connected to the first input of the corresponding frequency tuning block, the output is connected to the second input of the corresponding frequency tuning block, and the controlled input is connected to the output of the corresponding frequency tuning block. about 2. The system according to claim 1, characterized in that the frequency tuning unit of each selective filter contains a series-connected frequency detector and a first low-pass filter, as well as a series-connected phase detector, a second low-pass filter, an adder and a control element, the output of which is connected with a controlled input of a selective filter, while the first input of the unit with the tuning frequency is connected to the input of the frequency detector and the first input of the phase detector, the second input is koί. which is connected to the second input of the frequency tuning unit, and the output of the first low-pass filter is connected to the second input of the adder. 3. The system according to claim 2, characterized in that, in order to ensure linear adjustment characteristics of the selective filter, an optoelectronic pair containing a radiation source and a photoresistor is used as a control element, the radiation source being connected to the output of the adder of the frequency tuning unit, and The photoresistor is part of a selective filter.