RU1799788C - Device for measuring resistance of track circuit joints - Google Patents

Abstract

Usage: in the field of railway automation and telemechanics, in particular for measurements in rail circuits. The inventive device for measuring the resistance of the butt joints of the rail line contains an indicator,

Description

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voltage source 8 and amplifier and is equipped with two additional contacts and six additional isolation diodes, through which a sinusoidal voltage source is connected to the rails on opposite sides of the junction, and there are also sensors of four components of the measuring current through the diodes. Sensors connected through amplifiers

to the first inputs of the four voltage dividers, to the second inputs of which the voltage of the source is applied. The output signals of the first and fourth, second and third voltage dividers are summed in pairs by the adders, and the resulting signals are fed to two inputs of the adder, to the output of which an indicator 33 is connected. 1 ill.

The invention relates to the field of railway automation and telemechanics and can be used in the preventive maintenance of rail circuits and in the diagnosis of failures in them.

The aim of the invention is to increase the accuracy of measurements by eliminating the influence on the measurement result of the contact transient resistance and reducing the measurement time by simplifying the measurement procedure.

The drawing shows a structural diagram of the proposed device.

The device contains four contacts, the first T, the second 2, the third 3 and the fourth 4, with which it is connected to the rails 5 and 6 on opposite sides of the joint 7, and the third 3 and fourth 4 contacts are located at equal distances respectively from the first 1 and second 2 contacts. The first 1 and second 2 contacts are connected to the first terminal of the voltage source 8, respectively, through the first 9 and second 10 isolation diodes. The third contact 3 is connected to the second terminal of the voltage source 8 through the third 11 and fourth 12 isolation diodes connected counterclockwise in parallel branches, as well as through the first capacitor 13. The fourth terminal 4 is also connected to the second terminal of the voltage source 8 through the opposite counterparts in parallel branches x fifth 14 and sixth 15 are diode isolators, and also through a second capacitor 16.

The first 17, second 18, third 19 and fourth 20 current sensors, which can be used, for example, integrating circuits with magnetically sensitive elements, are connected to the inputs of the first 21, second 22, third 23 and fourth 24 selective amplifiers, respectively, connected their outputs, each with a first input respectively of the first 25, second 26, third 27 and fourth 28 voltage dividers. At the second inputs of the voltage divider 25, 26, 28 and 27

voltage is applied from the terminals of source 8 through amplifier 29.

The outputs of the first 25 and fourth 28 voltage dividers are each connected to

the corresponding input of the first adder 30, connected by its output to the first input of the second adder 31. The outputs of the third 27 and second 26 voltage dividers are each connected to the corresponding input of the third adder 32, connected by its output to the second input of the second adder 31, the output of which is connected to the inputs of the indicator 33 and the alarm unit 34.

The device operates as follows.

To take measurements, the device is pressed by contacts 1, 2,3,4 to rails 5, 6 on opposite sides of the conductive

junction 7. The current of the voltage source 8 then begins to flow along the following circuits. The current of one half-wave Ji from the first output of voltage source 8 flows through the first diode 9 and the first contact 1, and

then it flows in two parallel branches: current IV through a piece of rail between contacts 1 and 3, through contacts 3, a third diode 11 and a first capacitor 13 to a second terminal of voltage source 8; current And through a conductive junction 7 a piece of rail between contacts 2 and 4, the fifth diode 14, the second capacitor 16 and the second output of the voltage source 8. The magnitudes of the currents in these circuits are determined as follows

equations

It ll

R "1 + RKS + 2RA + ZP + Zc

(1)

, (2) 11 RK1 4-RK4 + ZCT-t-2RA + Zp + Zc W

where U is the voltage of the source 8;

Rd is the resistance of the diode; Zc is the capacitor resistance (Ci C2);

Zp is the resistance of the rail between contacts 1-3 or 2-4;

, KKZ, Ric4 - contact resistance of the contacts, respectively, 1.3.4.

ZCT is the measured joint resistance.

Similarly for the second half-wave of the voltage source current

12

U

R, c2 + RK4 + 2Rfl + Zp + Zc

(4)

. „

2 RK2 + RK3 + ZCT + 2Rfl + Zp + Zc

where RK2 is the transition resistance of the second contact 2.

The currents And, Ii, l2 and h are controlled by current sensors 17, 18, 19 and 20, respectively, and signals proportional to these currents are supplied from the sensors to the selective amplifiers 21, 22, 23 and 24. After amplification by a factor of K and filtering from interference signals proportional to the measured currents, respectively, kh1; kla and kla are supplied from the outputs of amplifiers 21, 22, 23 and 24 to the first inputs of the voltage dividers 25, 26, 27 and 28, respectively. The signal from the output of the amplifier 29 is proportional to the second voltage of the source to the second inputs of these dividers 8 - to U. As a result, at the output of the first voltage divider 25, in accordance with equation (1) there will be a signal

  Rki + Rk3 + 2Rfl + Zp + Zc (5) AND

The output signal of the second voltage divider 26 in accordance with (2)

- Pk1 + Pk4 + gSt + 2Rd + g + 2s. (6) And

The output signal of the third voltage divider 27 in accordance with (4)

- Rk2 + RK3 + ZcT + 2Rfl + Zp + Zc. (7) 2

The output signal of the fourth voltage divider 28 in accordance with (3)

U

(8)

- Rk2 + + 2RA + Zp + Zc. la

The output signals of the first voltage divider 25 and the fourth voltage divider 28 are summed by the first adder 30. Then, in accordance with (5) and (8), the output signal is M 2J1. the first adder will be proportional to the next value

.UZitaT + V Rki + Rk2 + RK4 +

H l2 + 4Ra + 2ZP + 2ZC.

The output signals of the third divider 27 and the second divider 26 after summing the third adder 32 will give a signal proportional in accordance with (7) and (6) the following value

   Rki + Rk2 + Rkz + Rk4 + li la

(3)

10

+ 2Zcr + 4Rd + 2ZP + 2ZC.

(YU)

The second adder 31 subtracts the output

signal of the first adder 30 from the output

signal adder 32. Then, in accordance

with (10) and (9) the signal at the output of the second sum 15 torus 31

U2 U23 -US 2 ZCT /

(eleven)

twenty

25

thirty

35

fifty

Therefore, the signal at the output of the second adder 31 is proportional to the measured value of the resistance of the conductive joint and the indicator scale 33 can be calibrated directly in units of resistance of the conductive joint, and the response threshold of the alarm unit 34 can be adjusted so that when the resistance of the joint increases to a critical value the alarm unit is triggered. The use of new elements, such as additional contacts, voltage dividers, and adders, favorably distinguishes the proposed device for measuring the resistance of conductive butt joints of a rail line from the specified prototype, since it increases labor productivity during measurements / and the reliability of the resultant. information on the condition of the conductive butt joints of the rail line, thereby reducing the amount of preventive maintenance work on the repair of butt connectors in the event of faulty rejection of serviceable ones. connections and reduced losses in train operation due to rail circuit failures when mistakenly accepted for serviceable joints in a precautionary state.

Claims (1)

SUMMARY OF THE INVENTION A device for measuring the resistance of a butt joint of a rail line, comprising one terminal connected through two contacts to the rails on both sides 55 A voltage source, voltage dividers, selective amplifiers, an adder and an indicator are distinguished from the conductive junction, characterized in that, in order to increase accuracy, it is equipped with an amplifier, current sensors, isolation diodes, additional adders and contacts for connection to rails installed at equal distances from the two contacts, between which the first and second isolation diodes are connected respectively to one terminal of the voltage source, and the third terminal of the voltage source is connected via the third parallel connected in parallel and the fourth isolation diodes and the first capacitor are the third contact, and through the fifth and sixth isolation diodes and the second capacitor are the fourth contact, the first, second, third second and fourth current sensors respectively connected to the inputs pervbgo, second, third and fourth selective amplifiers, the outputs of which are connected to the first inputs of the first, second, third and fourth dividers, respectively voltage, to the second inputs of which is connected another output of the voltage source through the amplifier, the outputs of the first and fourth voltage dividers are connected to the corresponding inputs of the first an adder connected by an output to one of the inputs of the second adder, the outputs of the second and third voltage dividers are connected to the corresponding inputs of the third adder, connected by the output to another input of the second adder, the output of which is connected to the indicator.