SU1509619A1 - Device for photoelectrical analysis of concentration of mechanical impurities in lubricant-coolants - Google Patents

Abstract

The invention relates to an optoelectronic measuring technique where high accuracy is required in determining the scattering, reflecting and absorbing properties of various liquids. The purpose of the invention is to improve the measurement accuracy. This is achieved by introducing into the measuring device an automatic gain control system with two electronic keys enabling it to be enlarged, reduced or memorized. 1 il.

Description

The invention relates to an optoelectronic test technique and can be used in measurements that require high accuracy in determining the scattering, reflecting and absorbing properties of various liquids.

Advantageously, the invention can be used to diagnose cutting fluids (coolant), namely, assessing the concentration of mechanical impurities.

The aim of the invention is to improve the measurement accuracy.

The drawing shows a block diagram of the device.

The device contains two measuring channels 1 and 2, insensitive to ambient light, each of the channels including illuminators 3 and 4 and photodetectors 5 and 6, block 7

control, measuring device 8, automatic control system 9 and recorder 10. At the same time, Automatic control system 9 includes a driver 11, first 12 and second 13 electronic keys with their control circuit 14, gain change block 15. The measuring device 8 comprises an amplifier 16 with a controlled gain control, a comparator 17 amplifier.

The measuring channels 1 and. 2 through the control unit 7 are connected to the first input of the measuring device 8, the first output of which is connected to the JO recorder, the second output to the shaper J J, and the second input of the measuring device 8 is connected to the output of the gain changing unit 15, the input

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which is connected to the outputs of the electronic switches 12 and 13, the inputs of which are connected to the power source, and the control inputs to the output of the control circuit 14 of the electronic keys, the input of which is connected to the output of the driver 11.

The device works as follows.

The input elements of the optical sensors are placed respectively in the reference (without mechanical impurities) and in the measuring coolant test. The signals generated by them, which are proportional to the optical density of the medium in the gap of the optocouplers, are fed to the control unit 7, which alternately switches them to the amplifier 16 at a frequency of f 50 Hz with an automatically controlled gain factor. The signal from the reference sensor in the amplifier 16 is amplified to a value of dp 10 V, followed by memorizing the gain. The signal from the measuring sensor is also through the unit

7 enters amplifier 16, where it is amplified with the same gain as the reference signal, and then subtracted from U. Difference signal proportional to the concentration of mechanical impurities

in the coolant is finally amplified and indicated in the recorder 10.

The optocoupler sensor pairs are placed alone in the coolant reference sample (i.e., without mechanical impurities), the other in the test sample. Consequently, at their outputs, signals are generated that are proportional to the optical density of the coolant and the sum of the optical density and concentration of mechanical impurities in the coolant, respectively. These signals are alternately fed to the input of the amplifier 16 with controlled gain control, KO, which works as follows. The signal from the reference sensor is amplified to the value of T - op O

In the case of a smaller or larger amplification factor, the comparator 17 generates a mismatch signal. The impulses generated in the generator 11, through the control circuit 14, use analog electronic keys 12 and 13 to control the gain control unit 15 by supplying a negative or positive one. voltage. This happens as long as it is standard. the signal after the amplifier does not become equal to U, j | while the gain is remembered.

At the next time point, the signal from the measuring sensor, which is amplified by the same number of times as the reference signal, arrives at the input of the measuring device. This signal is then subtracted from and dp.

After subtraction, a signal is formed that is proportional to the concentration of mechanical impurities in the coolant and is independent of the concentration of the coolant itself.

Claims (1)

The development of instruments for monitoring the concentration of mechanical impurities in liquids using the invention improves the accuracy when measuring extremely low concentrations of impurities in the coolant, whose optical density varies widely (due to changes in the content of emulsol or concentrate). Invention Formula A device for photoelectric analysis of the concentration of mechanical impurities in cutting fluids (coolant), containing two optical channels, an illuminator, a photodetector, a control unit, a measuring device connected through the control unit to the optical channels, an automatic control system and a recorder connected to the first output measuring device, characterized in that, in order to improve the accuracy of measuring the concentration of impurities in the coolant fluid, a second illuminator and a second photodetector are introduced into it, and The automatic gain control system is designed as a driver, first and second electronic keys with a control circuit and a gain change unit, the driver output is connected to the first input of the electronic switch control circuit, to the second input of which the second output of the control unit is connected, the output of the electronic control circuit the keys are connected to the control inputs of the electronic keys whose input is connected to a constant voltage source, and their output is connected to a change block gain, the output of which is connected to the input of the measuring device, the second output of which is connected to the input of the imager, with 1509619 This illuminators and photodetectors are made in the form of optocouplers placed one in the reference, and the other in the coolant samples under study.