SU1147930A1 - Device for measuring vibration amplitude - Google Patents

Abstract

A DEVICE FOR MEASURING A VIBRATION AMPLITUDE, comprising a master oscillator, a parametric vibration sensor, a series-connected detector and a recording unit, characterized in that, in order to improve measurement accuracy, it is equipped with a series-connected DC amplifier with a resistive negative feedback, a differentiating amplifier and a two-half-period With a rectifier whose output is connected to the detector input, a parametric vibration sensor is connected between the output of the master oscillator and the inverter The remote input of a DC amplifier with a resistive negative (L telnogo feedback, and the non-inverting input of the latter is grounded. 4 with 00

Description

The invention relates to an instrumentation and measurement technique and can be used to determine the parameters of the vibration process in testing and operating machines, building mechanisms, aircraft, etc. A device for measuring the parameters of the vibration process is known, comprising a series-connected generator, an inductive converter and an amplifier, as well as the lj indicator. The disadvantage of such a device is the low accuracy of the measurement of the scientific research institute, due to the additional error from the change in the active resistance of the inductive converter when the ambient temperature changes. Closest to the invention according to the technical nature of the device is a device for measuring the amplitude of vibration, comprising a master oscillator, a parametric vibration sensor f connected in series by a detector and a recording unit 2j. A disadvantage of the known device is the low accuracy of measurements, due to the error of the change in the active resistance of the vibration sensor when the ambient temperature changes. The purpose of the invention is to increase the measurement potential. The goal is achieved by the fact that a device for measuring the amplitude of vibration, containing a master oscillator, a parametric vibration sensor, a serially connected detector and a recording unit, is equipped with a series-connected direct current amplifier with resistive negative feedback (OOS), a differentiating amplifier and two-wavelength output By the driver, the output of which is connected to the detector input, the parametric vibration sensor is connected between the output of the master oscillator and the inverting input of the amplifier. This current with resistive OOS, the non-inverting input of the latter is grounded. . FIG. 1 shows the structures on the device diagram; in fig. 2 timing diagrams, by reference. The device for measuring vibration amplitude comprises, in series, an oscillator 1, a parametric vibration sensor 2, a DC amplifier 3 with resistive OOS, a differentiating amplifier 4, a full-wave rectifier 5, an envelope detector 6 and a recording unit 7. The device works as follows. The master oscillator 1 generates a signal of the square wave type, which is fed to the input of the parametric vibration sensor 2. At the same time as the master oscillator signal, the vibratory process acts on the oscillator, which changes its inductance. An inductive parametric vibration sensor can be represented by an equivalent circuit consisting of series-connected inductors L) (and resistance RX. Since from the downstream generator 1, the vibration sensor 2 is affected by a signal with a amplitude Uj ± E during each half-period, for example The output of the DC amplifier 3 varies with time as follows: V3 (t) .p (-R, t / L, where R0 is the reference resistor in circuit E is the amplitude of the oscillator. The signal at the output of the differentiating amplifier 4 is opi where обра is the time of differentiating amplifier 4, the amplitude of this expression is reversible proportional to the inductance value of the vibration sensor 2. When using an inductive vibration sensor with a variable gap, the inductance value L is inversely proportional to the size of the gap S , then the amplitude of april at the output of differentiating amplifier 4 is directly proportional to the value of gap 8, i.e. p is proportional to the amplitude of vibration and does not depend on the active co-winding of the inductive sensor.

At the output of the full-wave rectifier 5 there will be only positive polarity pulses.

U5 (t) - 2E R g - gexp (),

which, through the envelope detector 6, in the form of a voltage Ug, arrive at the registration unit 7, on which information on the vibration amplitude value will be reflected.

When measuring vibration parameters using a capacitive vibration sensor, the latter is included in the OOS circuit of the amplifier 3 constant

11479304

current with reference resistor R

in

input circuit. The operation of the device is similar to that considered. The voltage amplitude at the output of the differentiating amplifier is determined by the capacitance value of the sensor and does not depend on the value of the active loss resistance.

The use of this device allows one to increase the measurement accuracy by reducing additional errors caused by the influence of the parasitic parameters of the sensors on the measurement result and to extend the temperature range.

Claims (1)

DEVICE FOR MEASURING VIBRATION AMPLITUDES, comprising a master oscillator, a parametric vibration sensor, a serially connected detector and a recording unit, characterized in that, in order to increase the accuracy of measurements, it is equipped with a serially connected DC amplifier with resistive negative feedback, a differentiating amplifier and a half-wave rectifier, the output of which is connected to the detector input, a parametric vibration sensor is connected between the output of the master oscillator and the inverting Odom DC amplifier with a resistive negative feedback, and a non-inverting input of the latter is grounded. SU ... "1147930 FIG. 1 V.