SU761964A1 - Apparatus for measuring the concentration of ferromagnetic particles in non-conductive media - Google Patents

Description

The invention relates to the field of definition. division. the content of electrically conductive "particles in electrically conductive. x" liquid and solid media and can be used, for example, in the technical diagnostics of components and assemblies of machines working in liquid lubrication., ’'' /

A device is known for controlling the 'iron content in oil, consisting of a balanced single bridge', two "arms of which are made in type ⁴ active resistances, and the other two are in the form of inductances with series-connected active resistances," a step-up transformer with small own "capacity and capacity between the coils and the core ,. through which the bridge feeds. variables such and indicator [1].

; The downside ^! dunrro appliance is

the fact that an inductive sensor, 'which is one of the inductances of a single' bridge, reacts to the content in oil as ferromagnetic, yak 'and' non-ferromagnetic particles; In order to diagnose the components and assemblies working in their lubricant, it is necessary to know about the accumulation of ferromagnetic products of wear and tear, as the main parts, limiting the service life of the components and assemblies of the machine, '/

'made of ferromagnetic metals. -.3

‘. ./-'·· / UD-.

The closest in technical essence to the present invention is a device for determining ferromagnetic wear products in oil, consisting of an oscillating frequency generator connected to

, ·· / differential electromagnet dates. two-way amplifiers, a phase detector, a compensation element, a half-valued in the form of a potentiometer, included in the circuit of the phase detector, and a recording device [2]. The sensor is made in the form of a differential magnetic field; assembled on the core of the core, at the poles of which, there are ¹ four coils, powered by a low-frequency generator. In the middle part of the core there is a receiving coil, which is

- sensor output;

A disadvantage of the known device is that the compensation of the signal of a 'differential electromagnetic sensor,' due to the non-equivalence 'of its ο6ίΜότόκ,' is made using a ‘" tensiometer after its amplification, which is

>water'g. φ a decrease in the sensitivity of the device when determining the concentration of ferromagnetic particles in the oil; To increase the sensitivity of the device, it is necessary to increase the voltage in the magnetizing ^{1 of the} sensor, which leads to an increase in

ί

*

. „'L--: : -γ .- · Α?; τ.λ .- 'g / - .. ·

the residual magnetization of the core of the sensor and occurrence of interference signal, which can not be corrected and compensated directly on "sensor output ^h

“” before ”amplification with a graphite rod moved between the pole / pole of the sensor. It. leads to

, reduce the accuracy of determining the concentration of ferromagnetic particles. In oil. Using the device determine the ferro; magnetic impurities in oil samples with the lowest concentration of 1 GO ^-4 %. The two-step method of setting the device on bullets is quite complicated. In addition, after each new switch on of the device, the device is adjusted according to the reference contents of ferromagnetic particles, which reduces the productivity of labor in diagnosing engines and transmission units by analyzing samples of working oils. /.

The purpose of the invention is to increase the sensitivity and accuracy of measurements of the concentration of ferromagnetic particles of labor productivity by simplifying the setup of the device before measurements. _ν

Delivered tselts achieved by the fact that in the device for determining the concentration. ferromagnetic particles in non-conductive media, 'containing' / a low-frequency generator connected to a differential electromagnetic sensor, compensation element, amplifier and recording device, the compensation element is designed as a C-circuit with an adjustable phase connected to a low frequency generator an output connected to the first input of the comparison device, to the second input of which a differential electromagnetic sensor is connected, with the output of the comparison electromagnetic

"'· Devices" are connected in series through a selective amplifier and a linear rectifier with a recording device.

FIG. 1 is given a block diagram of the proposed device; in fig. 2 - electrical schematic diagram of the compensation element. ^;

The “7 *” device consists of a low-frequency generator 1, connected via a buffer amplifier 2 with a differential electromagnetic sensor 3 and a com- mungable 'common ^ eYaM'ent' 4, comparing the devices' 5, whose Schyo's are connected to

¹ outputs of the compensation element 4 and sensor 3, N 'Nykhod' - "e selective

. amplifier 6, 'NODK'lYuchen'Nyy through a linear rectifier 7'^;'to ^g ' register

device 8. "/ /// '// 7’ /. 77/7.,. 777 /.,. 7 7.

Compensation Element 'is made in

. the form of a phase shifter assembled in a trance;

formatter Tr. The phase-shifting circuit includes the resistor Κι.and capacitor C. The resistor /? ₂ serves to suppress the parasitic sensor signal in amplitude.

The device works as follows / - ZOM ... ',. ^one

⁵ 'Before measurement, the sensor signal is adjusted to zero using resistors Κι and /? 2 of the compensation element Va. That check indications of the registering device, ·? on reference samples with known,

10 concentrations of ferromagnetic particles in the oil. After that, a test tube with a sample of the waste oil taken from the engine, with an unknown concentration of ferromagnetic particles is placed in the socket

15 sensor 3. As a result of the imbalance of the differential of the magnetic bridge on you-.

During sensor 3, a signal appears through the selective amplifier 6 and the linear rectifier 7 to recording device 8, which shows the magnitude of the concentration of ferromagnetic particles.

from a mixture of tea leaves in oil. When removing the tube with the oil sample from sensor 3, the compensation of the magnetic field of the sensor is automatically set.

The proposed device provides

'an increase in the sensitivity and accuracy of determining the concentration of ferromagnetic particles in non-conductive media from

30 1 · 10 ^-4 to 1 · 10 ^_7 %. This is probably a benefit: through the use of a compensation element made in the form of a phase-shifting /? C-circuit connected to a low-frequency generator with an adjustable output, of a 35-amplifier amplifier and a linear rectifier. In addition, the device simplifies zero setting and eliminates the need for reconfiguration before the next determination of concentration, which is especially important when conducting diatality. “· The knowledge of a large machine-tractor park, as this increases the productivity of labor.

The device conducts diagnostics

45 units of cars, tractors, etc., directly in fleets and in the field, out of conditions, without using expensive laboratories? . . ' 50

Claims (1)

Claim A device for determining the concentration of ferromagnetic particles in non-conducting media, comprising a generator 55 A low frequency coupled to a differential electromagnetic ... sensor, a compensation element, an amplifier and a re, a test device, characterized in that, in order to increase the sensitivity and accuracy of measurements, the compensation element is designed as a phase shifter connected to the generator. - gayuschey 7? With-chains with an adjustable output, * connected to the first input of the comparison device, to the second input of which / five A differential electro magnetic sensor is connected, the output of the comparison device is connected via a series-connected selective amplifier and linear rectifier with a recording device. 761964 6 ' -