SU964505A1 - Pressure measuring device - Google Patents

Description

(54) DEVICE FOR MEASURING PRESSURE

one .

The invention relates to instrument making and can be used to measure pressure and mechanical deformations in control and regulation equipment.

Closest to the invention is a pressure measurement device comprising a resistor and a semiconductor strain gauge connected in series and connected to a power source in a non-conductive direction, the semiconductor strain gauge being connected to the information transmission line. schga 1.

A disadvantage of the known device in it is the low accuracy of measurements, due to the use of a direct current signal as an output value.

The purpose of the invention is to increase the accuracy of measurements.

The goal is achieved by the fact that the device is equipped with at least one additional strain gauge and adder, and each strain gauge. - a narrow-band filter whose output is connected to the input

adder, - and the adder output is connected to the information transmission line.

FIG. 1 is a schematic diagram of the device; in fig. 2 - graphs of the spectra of the signals from the outputs of two strain gauges of the device; in fig. 3 shows an example of using the device in a remote control system.

The device consists of a strain gauge 1, a narrowband filter 2, an adder 3 and a line

10 4 transmission of information.

Device) works as follows.

The input signal in the form of a certain pressure level acts on the strain gauge 1. Depending on the pressure, the breakdown voltage

15 strain gauge can be more or less voltage supply. Accordingly, the avalanche test of the strain gauge is absent or takes place. In the presence of avalanche sampling, the strain diode generates a broadband noise

20 signal. Part of the spectrum of the broadband noise signal is extracted by narrowband filter 2 and carries information about the level of pressure acting on the strain gauge.

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At the initial breakdown level, the level of the generated noise signal linearly depends on the QT pressure. For each strain gauge used in the device, its corresponding filter is adjustable to its own band.

transmissions, and the frequency intervals of the filter transmissions for different strain gauges do not intersect, therefore, after adding the signals from the strainer filters in the adder 3, the signals can be transmitted via one information transfer line 4. This is illustrated by the graphs of the spectra (Fig. 2), from which it can be seen that the noise signals from the filter outputs of the gas diodes can be located far from the zone of intense interference, which ensures the accuracy of the measurements.

With changes in temperature and voltage, the accuracy of measurements can be; increased by using the differential inclusion of each strain gauge with respect to one of them, operating in the absence of an input pressure signal (Fig. 3).

The technical and economic efficiency of the invention is to improve the measurement accuracy by placing the output signals in a frequency zone free from industrial interference, as well as to improve the efficiency of using information transmission.

Claims (1)

Invention Formula A device for measuring pressure, containing a semiconductor strainer connected in a non-conductive direction to the source of piercing, and an information transmission line, characterized in that, in order to improve the measurement accuracy, it is equipped with at least one additional tensorodiode and adder, and each strainer with a narrowband filter , the output of which is connected to the input of the adder, and the output of the adder is connected to the information transmission line. Sources of information taken into account in the examination 1. Krivrnosov I. I. Semiconductor electroacoustic transducers. M., Energie, 1977, fig. 30 (prototype). . Th t five% L, 1 J