RU1775043C - Gas analyzer - Google Patents

Abstract

Usage: in analytical instrumentation, solving problems of gas analysis by the method of heat conduction. The inventive gas analyzer contains a constant voltage source, a bridge measuring circuit with a combined double bridge, normalizing amplifiers for measuring U0 and comparative Ucp signals, a nonlinearity correction signal generator with an analog adder and a constant divider with a constant divider, linear analog-to-digital divider, reference voltage source and indicating device. When applying the numeric X and significant Y inputs of the analog-to-digital divider for m signals KiUp and Ka / Ucp +, respectively, and when the coefficient n is accurately selected, a signal is sent to the input of the indicating device as a function of concentration in percent. 2 ill. s w y

Description

The invention relates to analytical instrumentation, in particular to gas analytical instruments, and can be used to solve a wide class of problems of gas analysis by the method of thermal conductivity.

A gas conductivity analyzer is known based on an automatic comparator, voltage circuit, which contains a measuring bridge circuit consisting of measuring and comparative sensitive elements and a comparative bridge circuit, in the shoulders of which are thermosensitive elements enclosed in ampoules with gas corresponding to the beginning of the measurement scale instrument.

The closest technical solution is a gas analyzer containing stabilized and adjustable power sources for bridge measurement circuits, nonlinearity meters, a comparison unit, a controlled divider and an adder.

The disadvantages of the known gas analyzer are doubled mass and dimensional and power indicators of the sensor unit, the complexity of the implementation and configuration of the non-linearity measurement units, and the absence of a compensation scheme for influencing components.

The aim of the invention is to increase the accuracy of the analysis by including an additional nonlinearity correction signal generator in the gas analyzer circuit.

This goal is achieved by the fact that as a bridge measuring circuit use a combined circuit of a double measuring bridge, and this measuring bridge contains one open

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a sensor element washed by the analyzed gas, one closed sensor element filled with a mixture, the composition corresponding to the end of the scale, and two closed sensor elements filled with a mixture, the composition of which corresponds to the beginning of the scale and an additional nonlinearity correction signal generator is introduced into the signal conversion device, consisting of from an analog adder and a divider with a fixed division factor and a high-precision analog-to-digital divider of two analog signals and a reference source voltage for analog-to-digital divider.

Figure 1 presents a functional diagram of a gas analyzer; figure 2 shows a structural diagram of a combined dual measuring bridge.

The gas analyzer contains a constant voltage source 1, a bridge measuring circuit with a combined double bridge 2, normalizing amplifiers of the measuring 3 and comparative 4 signals, a non-linearity correction signal generator 5 with an analog adder 6 and a signal divider with a constant division factor 7, analog a digital divider 8, a reference voltage source 9 and an indicating device 10, the measurement output of the bridge circuit 2 being connected via a normalizing amplifier of the measuring signal 3 to the digital input X tax-digital divider 8 and the comparative output of the bridge circuit is connected to the input of the normalizing amplifier of the comparative signal 4, at the same time the measuring and comparative output are connected to the input of the analog adder 6, the output of the analog adder is connected to the input of the signal divider with a constant coefficient 7, the output of which is connected to the input the reference amplifier of the comparative signal 4. The output of the reference amplifier 4 is connected to the significant input of the analog-to-digital divider 8, the reference voltage source S with one with an analog-digital divider 8, output of the analog-to-digital divider is connected to the showing apparatus 10,

The combined dual-bridge bridge measurement circuit contains a Un power supply, one open sensing element Rv, which is washed

analyzed gas, closed sensitive R "filled with a mixture corresponding to the end of the scale and two closed sensitive elements RH. filled with the mixture corresponding to the beginning

scales and two constant resistance R0.

Claims (1)

SUMMARY OF THE INVENTION A gas analyzer comprising a bridge connected to a power source a measuring circuit with measuring and comparative thermosensitive elements connected to this circuit through a signal conversion device, a meter, characterized in that, in order to To increase the accuracy of the analysis, a combined scheme of a double measuring bridge containing one open sensor element washed by the analyzed gas, one closed sensor element filled with a mixture of the composition corresponding to the end of the scale, and two closed sensor elements filled with a mixture of the composition corresponding to the beginning of the scale, and an additional nonlinearity correction driver containing analogs is introduced in the signal conversion device th adder and divider with a fixed division coefficient, and the inputs of the analog adder are connected to the outputs of the measuring and comparative sensitive elements, and the output of the analog adder is connected through a divider with a fixed division factor to the summing input of the normalizing signal amplifier of the comparative sensor, an analog-digital divider, the digital input of which connected to the output of the normalizing amplifier of the measuring signal, and the significant input connected to the output of the normalizing amplifier of the comparative signal, m reference voltage source for analog to digital divider. l i