SU1670691A1 - Indicator unit and audible signalling - Google Patents

Abstract

This invention relates to mass spectrometry control and allows for improved performance and reliability by improving performance and ensuring device operability under conditions of high humidity and temperature. The display and audible alarm device contains a serially connected electrometric amplifier 1, a normalizer 2, an analog-to-digital converter 3, a microprocessor system 4, a binary counter 5, an audio frequency generator 6 and a loudspeaker 7, a generator of 8 rectangular pulses and a digital display 9. The device has An indication of a two-digit number in six bits and a power indicator in two bits. The level of a gas leak is judged by the repetition frequency of pulses filled with an audio signal. 1 il.

Description

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The invention relates to instrumentation engineering, in particular to mass spectrometric tightness monitoring.

The purpose of the invention is to increase productivity and reliability by increasing speed and ensuring operability under conditions of elevated humidity and temperatures.

The drawing shows a block diagram of the device.

The display and audible signaling device comprises a serially connected electrometric amplifier 1, a normalizer 2, an analog-digital converter 3, a microprocessor system 4, the second output of which is connected to the control inputs of the electrometric amplifier 1, a normalizer 2 and an analog-digital converter 3, a binary counter 5, the first input of which is connected to the data output of the microprocessor system 4, an audio frequency generator b and a loudspeaker 7, 8 rectangular pulse generator, the output of which is soy dinene with the second input of the binary counter 5, and a digital display 9, the input of which is connected to the data output of the microprocessor system 4.

The device works as follows.

The magnitude of the ion current at the input of the electrometric amplifier 1 can vary within four decades, but taking into account the set value of the overall transfer coefficient from the input of the electrometric amplifier 1 to the input of the analog-digital converter 3 and the capabilities of the latter, the input signal after the normalizer 2 can only be changed within one decade. The values of the conversion coefficient of the input ion current of the electrometric amplifier 1 to the voltage and the transfer ratio of the normalizer 2 are performed by control signals of the microprocessor system 4. Changing the input voltage of the analog-digital converter 3 within one decade allows an eight-digit code number obtained on its output, to display a signal with a resolution of 1-2%, which is acceptable for common industrial mass spectrometric leak detectors. The indication of the result of the evaluation of the magnitude of the gas leak is produced on the digital display 9 in the form of a two-digit number and an exponent. At the same time, six bits of eight digits at the output of microprocessor system 4 are used to indicate a two-digit number, and

to indicate the exponent - the remaining two digits. From these two bits, signals are generated to control the overall gain. With help

the preset counter 5 converts the equivalent of the result of estimating the magnitude of the gas leak into a variable frequency signal. Six digits of the number from the output of the microprocessor system 4 used to form the number on the digital display 9 are fed to the inputs of the six least significant bits (data input) of the eight-bit counter 5. Generator 8 pulses are sent to its counting input with a low frequency (then For 50Hz), From the switching output of the counter 5, the overflow signal is fed to its preset input. From the moment the pulses of the generator 8 are fed to the counting input of the counter 5

the counting cycle begins and the high-order bit of this counter is zeroed. Counter 5 continues counting generator 8 pulses and reaches overflow after a time determined by a six-digit number at the data input of counter 5. With a small value of this number, the time after which overflow of counter 5 occurs is large, while the large value of this number is time small . Accordingly, the frequency of the signal generated at the output of the higher bit of the counter 5. in the first case will be lower, and in the second - higher. Thus, the amplitude modulation of the generator 6 is carried out by pulses

the frequency of which is proportional to the level of the ion current | entering the device from the analyzer output of the leak detector. Loudspeaker 7 converts the infrared-frequency-tuned signal

sound frequency in the audio signal perceived by the ear organs of the operator. By the repetition frequency of pulses filled with an audio signal, the magnitude of the gas leak is judged by visually determining the intended location of the object and the object. in the absence of a gas leak, the zo pulses (the second frequency is repeated rarely enough

When the sensor is installed in place of the maximum gas leakage, the pulse repetition frequency of the audio frequency will be maximum. At this point, the digital display 9 shows the maximum signal level.

A new construction of the gas leak indication and sound signaling device for the leak detector and the use of new elements in it in a particular inclusion distinguishes the proposed device

Claims (1)

from the prototype, since it automates the process of controlling the level of the gas flow, i.e. The efficiency and productivity of testing objects for leak tightness is significantly increased. At the same time, the introduction of a digital display 9 (which became possible in the new structure) instead of a switch instrument provided an increase in the reliability of the device and a high response rate when reading the level of a gas leak. The invention The display and audible alarm device containing a series-connected electrometric amplifier and a normalizer and an audio frequency generator and a loudspeaker is distinguished by Now, with the Purpose of improving performance and reliability, it includes series-connected analog-to-digital converter, the input of which is connected to the output of the normalizer, microprocessor system, the second output of which is connected to the control inputs of the electrometric amplifier, normalizer and analog-digital a converter, and a digital display, a binary counter, the first input of which is connected to the data output of the microprocessor system, and the output - to the input of the sound frequency generator, and a square generator pulses, the output of which is connected to the second input of the binary counter.