SU794376A1 - Apparatus for measuring movement parameters - Google Patents

Description

one

The invention relates to devices for electrical measurements of non-electrical quantities and may be used to measure the movement of an acceleration vibration.

A device for measuring motion parameters is known, comprising a sensor, an amplifier-limiter, a differentiating chain, a frequency doubler, a multivibrator, a detector, and an indicator. In such a device, there is a significant distortion of the measured complex harmonic vibration processes, which leads to inaccurate measurements 1.

The closest to this technical solution is a device for measuring motion parameters, which contains a differential capacitive sensor associated with generators of different polarity pulses connected to the pulse conversion channels, and a recording unit. For some measurements, the sensitivity of this device is insufficient 2.

The purpose of the invention is to improve the measurement accuracy by increasing the sensitivity of the device and obtaining a linear dependence of the output voltage of the device on movement.

The goal is achieved due to the fact that each pulse conversion channel contains two subchannels, the first of which consists of successively connected pulse selector of positive polarity, a shaper of positive rectangular pulses and a detector of positive rectangular pulses, and the second subchannel of successively connected pulse selector of negative polarity generator of negative rectangular pulses and detector of negative rectangular pulses, the outputs of the detector put Yelnia rectangular pulses of the first channel detector and negative rectangular pulses of the second channel are connected to inputs of the first adder increments modulo voltages, and the detector outputs the negative rectangular pulses of the first channel

and the detector of the positive rectangular pulses of the second channel are connected to the inputs of the second voltage increment modulo, the outputs of the voltage increment adders are modulo connected to the inputs of the differential DC amplifier, the output of which is connected to the recording unit.

The drawing shows a functional diagram of a device for measuring motion parameters.

The device contains a differential capacitive sensor I, identical generators 2 and 3 of different polarity nanos pulses, selectors 4 and 5 pulses of positive polarity, selectors b and 7 pulses of negative polarity, shapers 8 and 9 positive rectangular impulses, shapers 10 and 11 negative rectangular impulses, detectors 12 and 13 positive rectangular pulses, detectors 14 and 15 negative rectangular impulses, adders 16 and 17, voltage increment modulo, differential amplifier 18 constant current and recording unit 19.

The device works as follows.

Each of the generators 2 and 3, during which the driving circuits of which are connected respectively to the outputs of the differential capacitive sensor 1 with a grounded (common) moving plate, produces different polarity voltage pulses of the same frequency and amplitude, shifted in phase by an insignificant value, which compensates for the separation of positive and negative pulse generators 2 and 3 selectors. From selectors 4 and 5, positive-positive pulses come to identical formers 8 and 9 positive square-voltage pulses, respectively, and from selectors 6 and negative polarity, to identical formers 10 and 11 negative rectangular-shaped pulses .

The voltage pulses at the outputs of the formers 8 and 9, 10 and I have the same frequency, duration and amplitude in magnitude, and therefore, at the outputs of detectors 12 and 13, 14 and 15, the values of the detected pulses will be equal in magnitude. The voltage of the detected positive pulses with the detectors 12 and the voltage of the detected negative pulses from the detector 15 are fed to the inputs of the adder 16, and from the outputs of the detectors 13 and 14 to the inputs of the adder 17. From the outputs of the adders 16 and 17, the voltage goes to the differential amplifier. In the absence of movement of the movable plate of sensor 1 at the output of the voltage amplifier will be zero.

When moving to either side of the movable plate of sensor 1, the capacity of one co-core increases and the other decreases, which causes, for example, a decrease in the pulse frequency of the generator 2 and an increase in the pulse frequency of the generator 3. This leads to a decrease in the positive voltage at the output detector 12 and a negative voltage at the output of the detector 14 and to a corresponding increase in voltages at the outputs of the detectors 13 and 15. At the outputs of the adders 16 and 17, voltage increments are formed opposite to s sign and exceeding increments modulo voltages at the outputs of each detector in half.

Coming from the output of the differential amplifier 18 to the recording unit

19, the electrical signal will proportionally display the motion parameters.

(displacement, vibration, acceleration).

Cross-connecting the inputs of the adders 16 and 17 allows for the suppression of different polarities, and using a differential amplifier, unipolar disturbances are suppressed. In addition, the level of the useful signal increases, which leads to an increase in sensitivity, and consequently, n accuracy.

Claims (2)

1. "Technique of film and television, 1971, No. 1, p. 7 2. USSR author's certificate, № 457376, cl. G 01 D 5/24, 1974. eight // 12 15 / J