SU1698652A1 - Vibrations controlling unit - Google Patents

Abstract

The invention relates to a measurement technique and can be used to control the technical condition of moving parts of machines during their operation. The purpose of the invention is to expand the functionality by determining the ratio of the harmonic period, having a large amplitude, to the period of the reverse frequency. During operation, the device monitors the overall level of vibrations and, if this excess is determined by one of the harmonics, determines the ratio of the period of this harmonic to the period of the reverse frequency. 1 il.

Description

The invention relates to a measurement technique and can be used to control the technical condition of moving parts of machines during their operation.

The purpose of the invention is to expand the functionality by determining the ratio of the harmonic period, having a large amplitude, to the period of the reverse frequency.

The drawing shows a block diagram of the device.

The device for controlling vibrations comprises a vibration transducer 1 connected in series, an amplifier 2, a first amplitude detector 3 and an indicator 4, a series-connected limiter 5, an input connected to the output of amplifier 2, an integrator 6, a sampling and memorizing circuit 7, a first differentiating element 8, the second amplitude detector 9, scaling amplifier 10, summing amplifier 11, threshold element 12 and actuator 13, second differentiator

14, the input of which is connected to the output of the first amplitude detector 3 m by the second input of summing amplifier 11, and the output to the third input of summing amplifier 11. the first driver 15, whose input is connected to the output of limiter 5. and the output to the control input of sample 7 and storing, a reset circuit 16, the input of which is connected to the output of the imaging unit 15, and the output - to the control input of the integrator 6, the speed sensor 17, the frequency multiplier 18, the And element 19, the counter 20, the memory register 21 and the digital indicator 22 , after before trigger-connected trigger 23, whose input is connected to the output of the first driver

15, the second driver 24 and the delay element 25, the output of which is connected to the Reset input of counter 20, and the second threshold element 26. whose input is connected to the output of the second amplitude detector 9, and the output to the second input of the And 19 element, the third input of which is connected to trigger output 23, and the input Record register memory tm connected to the output of the second shaper 24.

The device works as the next cut,

The signal from the output of the vibrator 1 through the amplifier 2 is fed to the input of the first amplitude detector 3, rectified and smoothed and fed to the indicator 4, where the average value of the measured value is displayed,

From the output of the first amplitude detector 3, the average value of the rectified voltage goes to the second input of summing amplifier 1, and through the third differentiating link 14 to the third input of summing amplifier 11 receives a voltage proportional to the rate of increase of the measured value.

The signal x (t) from the output of the amplifier 2 is fed through the limiter 5 to the input of the integrator 6.

From the output of the 17-turn sensor, a signal with a period T0 goes to a frequency multiplier 18, from the output of which pulses with iA-part f К / That, where K is the frequency multiplication factor, goes to the first input of the element 19, to the second input to which the signal from the output of the threshold element 26.

At the output of the limiter 5, pulses U0 of positive polarity are formed with a constant amplitude and duration equal to the time when the voltage x (t) exceeds the zero level voltage.

At the output of the integrator 6, sawtooth pulses are formed with an amplitude A proportional to the duration of the cob U0.

The first driver 15 generates a short pulse U i at the time of the falling edge of the pulse Uo. The impulse Ui arrives at the control input of the sampling circuit 7 and zepomi. nani. During the pulse Ui, the signal amplitude of the non-signal input of the sampling and storage circuit 7 is A, This signal value is memorized by the sampling and storage circuit 7 and through the first differentiating element 8, the second amplitude detector 9 and the scaling amplifier 10 enters the input of the summing amplifier 11.

The pulse Ui arrives at input 16 of the reset, at the output of which a short pulse U2 is formed at the moment when the pulse Ui ends.

The impulse U2 arrives at the reset input of integrator b and sets it to its initial state, at which the signal at its output is zero.

The pulse Ui arrives at the counting input of the trigger 23 and switches its state. At the output of the trigger 23, positive pulses of duration Tx are formed, which are fed to the third input of the element I 19.

At the output of the sampling and memorizing circuit 7, a step signal is generated, the value of which is proportional to the current time value exceeded by the signal

0 x (t} is zero.

If the signal from the vibration converter 1 is periodic, the signal at the output of the sampling and memorizing circuit 7 will be constant (for example, for a sinusoidal signal x (t) X0sin 2l t / Tx the signal at the output of CXCML: 7 sampling and memorization will be proportional to Tx) and the pulse duration at the trigger output will be equal to the period x (t). At the output of the first differentiator 12, the signal will be zero. Therefore, at the first input of summing amplifier 11, the signal will be zero, i.e. for a periodic signal, the signal at the output of summing amplifier 14 depends on

5 only from the average value of the measured value and the rate of increase of the average value.

The zero signal from the output of the second amplitude detector 9 is fed to the input

0 of the second threshold element 26, at the output of which a signal of a logical unit is formed, which is fed to the second input of the element 19.

Thus, if the signal x (t) is periodic, then counter 20 will count pulses with a frequency f K / G0. coming through the element And 19 with the output of the multiplier 18 frequency for the time Tx.

In the counter 20, the number N f is formed.

0 Tk K Tx / To, which is recorded in the memory register 21 at the moment it arrives at its input. Record a short pulse Uz from the output of the second driver 24 at the time of the falling edge of the pulses from the trigger output.

5 23, after which the pulse Us is delayed by the delay element 25 and is fed to the input Reset of the counter 20, which sets it to its initial state. The number N, recorded in register 21 of memory, is proportional to

0 to the ratio of the period of the periodic component of the vibration to the period of rotation of the part. This number is displayed on digital display 22 and allows identification of a source of increased vibration.

If the signal from the vibration transducer 1 is random, the signal at the output of the sampling and storage circuit 7 will change randomly in proportion to the current time value exceeding the zero level signal.

The random signal from the output of the sampling and memorizing circuit 7 after the first differentiating element 8 is rectified in the second amplitude detector 9, and through the scaling amplifier 10 the average value of the derivative of this signal goes to the first input of the summing amplifier 11.

The signal from the output of the second amplitude detector 9 will trigger the second threshold element 26. A logical zero signal from the output of the second threshold element 26 will block the passage of pulses from the output of frequency multiplier 18 through element 19 to the input of counter 20.

The counter 20 will be in the zero state, zero will be fixed in the memory register 21 and on the indicator 22, which indicates the random nature of the vibration.

The output signal from summing amplifier 11 through threshold element 12 turns on an actuator 13, which serves to give a warning signal about a dangerous change in the nature or level of vibration or to turn off a controlled machine.

Claims (1)

Invention Formula A device for controlling vibrations, containing a vibration transducer connected in series, an amplifier, a first amplitude detector and an indicator, a series-connected limiter whose input is connected to the output of an amplifier, a tegrator, a sampling and memory circuit, a first differentiating element, a second amplitude detector, a scaling amplifier, a summing amplifier, a threshold element and an actuator, a second differentiating element whose input is connected to the output of the first amplitude detector and the second input of the summing amplifier, and the output to the third the input of the summing amplifier, the driver, the input of which is connected to the output of the limiter, and the output to the control input of the sampling and storage circuit, and a reset circuit, the input of which is connected With the output of the imaging device, and the output with the controlling input of the integrator, characterized in that, in order to expand its functionality, it is equipped with a series-connected speed sensor, a frequency multiplier, an And element, a counter, a memory register and a digital indicator sequentially connected with a trigger, the counting input of which is connected to the output of the imager, the second driver and the delay element, the output of which is connected to the Reset input of the counter, and the second threshold element whose input is connected to the output m second amplitude detector, and an output - to a second input of AND gate, the third input of which is connected to the trigger output and the input recording memory register coupled to the output of the second shaper.