JP2017187384A - Rail wear measuring method using eddy current type sensor, and measuring apparatus therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rail wear measuring method that is mounted on a track inspection car to speedily and accurately measure rail displacement and rail wear during a travel by using both a coil for measuring rail displacement and a coil for measuring wear together, and performing arithmetic processing on measurement results thereof.SOLUTION: A rail wear measuring method comprises: using a rail displacement sensor 2 having a coil 1 (Co1) and a coil 2 (Co2) to output, as an output voltage Vo, impedance variation varying depending upon displacement x of a rail R and a lift-off z, and measuring the output voltage Vo to detect the displacement x of the rail R; using a wear sensor 3 having a coil 3 (Co3) to output, as an output voltage Vo, impedance variation varying depending upon a wear quantity La of the rail R, and measuring the output voltage Vo to detect the wear quantity La of the rail; calculating a difference between a voltage VT associated with the coil 1 and coil 2 and a voltage VR associated with the coil 3 to obtain a wear detection voltage VLa; and determining whether the rail R has worn from the wear detection voltage VLa.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a measurement technique for measuring rail wear using an eddy current sensor when detecting the displacement of a rail used for a railway track, and in particular, this rail without contacting the rail while the vehicle is running. The present invention relates to a rail wear measuring method using an eddy current sensor capable of detecting the displacement and wear of the rail, and a measuring apparatus thereof.

Tracks (rails) that support vehicles such as trains that pass several hundred times a day are worn by friction with the wheels of the train. Rail wear depends on various environmental factors such as the weight applied to the rail when passing through the train, the type of train, the operating conditions and rail maintenance status, the presence or absence of rail oiling, the gradient, rainfall / snowfall, humidity, and temperature. Is attributed. Further, the rail is displaced in the lateral direction by traveling of the train or the like. That is, the positions of the rail top surface and the side surface are shifted. It is necessary to carry out track maintenance work in order to increase the safety of traveling such as trains.
In this way, the rail of the railroad track is worn a little every day. From the viewpoint of safety, it is necessary to regularly manage the degree of wear of the rail with numerical values and to effectively maintain and repair it. When the wear of the rail progresses greatly, it is necessary to replace the rail.

  As a conventional method of measuring the amount of wear of the rail, there is a method in which a person goes to the site and uses a measuring instrument such as a rail wear ruler. The change in rail shape due to wear varies widely, and there are many rails to be measured. Therefore, a method of measuring rail wear during running of a railway vehicle such as a test vehicle is desirable. For example, in railway track maintenance, an eddy current type rail displacement sensor that has little influence on rainfall and snow cover is used for a track inspection vehicle that measures rail gaps and traversing errors. This eddy current type rail displacement sensor is a sensor that outputs a voltage corresponding to a lateral displacement of the rail without contact. The eddy current type rail displacement sensor includes a coil, a coaxial cable, and an output voltage circuit. It has been confirmed that the shape change due to wear of the rail affects the output of the eddy current type rail displacement sensor.

  Various techniques relating to a method of detecting a shift of a rail, that is, a displacement amount in a non-contact manner while the vehicle is running have been proposed. For example, a pair of detection coil means installed on the left and right sides of the rail longitudinal direction center line as disclosed in Japanese Patent Application Laid-Open No. 2013-238516 “Eddy current type rail lateral displacement detection method and apparatus” Is excited by a high-frequency resonance current, the impedance change of the pair of detection coil means is converted into a DC voltage, the DC voltage is converted into a digital signal, and the rail and the rail are converted based on the voltage value of the converted digital signal. An eddy current rail lateral displacement detection method for detecting lateral displacement between the pair of detection coil means has been proposed.

JP2013-238516A

  However, in the “eddy current type rail lateral displacement detection method and apparatus” of Patent Document 1, the rail displacement output is affected by the amount of wear on the rail top caused by the friction between the rail wheel and the rail contact portion. There was a problem that high-precision measurement was not possible. For example, at a curve location on a railway track, the amount of wear tends to increase due to the uneven distribution of the load inside the rail located outside the curve.

  The inventors of the present invention have focused on the fact that the rail displacement output is affected by the amount of wear at the rail top caused by the friction of the contact portion between the railway wheel and the rail. Therefore, we thought that the rail wear could be measured more accurately by measuring the rail displacement and the rail wear at the same time. The change in the rail shape due to wear is quite different, and it is thought that the displacement and wear of the rails that are many measurement objects can be detected quickly.

  The present invention has been developed to solve such problems. That is, the object of the present invention is to use a coil for measuring the rail displacement and a coil for measuring the wear together, and by processing the measurement result, the rail displacement and the rail are mounted while running on the track inspection vehicle. It is an object of the present invention to provide a rail wear measuring method using an eddy current type sensor capable of measuring wear quickly and accurately and a measuring apparatus therefor.

The rail wear measuring method of the present invention uses a eddy current type sensor (1) that causes a current to flow through a coil to generate an eddy current in the rail (R) and measures displacement and wear of the rail (R). A measuring method,
Using a rail displacement sensor (2) having a coil 1 (Co1) and a coil 2 (Co2), an impedance change that changes depending on the displacement (x) and liftoff (z) of the rail (R) is output voltage ( Vo), and the displacement (x) of the rail (R) is detected by measuring the output voltage (Vo).
For the output voltage (Vo) measured by the coil 1 (Co1) and the coil 2 (Co2), displacement correction and linearization are performed,
Using a wear sensor (3) having a coil 3 (Co3), an impedance change that changes depending on the wear amount (La) of the rail (R) is output as an output voltage (Vo). ) To detect the amount of wear (La) of the rail (R),
The output voltage (Vo) measured by the coil 3 (Co3) is subjected to displacement correction and linearization,
The wear detection voltage (VLa) is obtained by taking the difference between the voltage (VT) related to the coil 1 (Co1) and the coil 2 (Co2) and the voltage (VR) related to the coil 3 (Co3), and this wear detection voltage (VLa). To determine whether or not the rail (R) is worn.
For example, the coil 1 (Co1) and the coil 2 (Co2) of the rail displacement sensor (2) are measured so as to face each other in the lateral displacement direction with respect to the longitudinal direction of the rail (R).

The rail wear detection device of the present invention is a rail wear detection device using an eddy current sensor that measures the displacement and wear of the rail (R) in a contactless manner while running on a track inspection vehicle,
A rail displacement sensor (2) comprising a coil 1 (Co1) and a coil 2 (Co2) for generating a high-frequency magnetic field by flowing a high-frequency current through the rail (R) for measuring the displacement of the rail (R). ,
A high-frequency magnetic field is generated by supplying a high-frequency current to the rail (R) for measuring wear of the rail (R) provided at a position adjacent to the coil 1 (Co1) and the coil 2 (Co2). A wear sensor (3) comprising a coil 3 (Co3)
An amplifier (23) for amplifying the output signals of the coils 1 (Co1) and 2 (Co2), an amplifier (23) for amplifying the output signals of the coil 3 (Co3),
A converter (22) for computing the output signals of the coil 1 (Co1) and coil 2 (Co2) and the output signal of the coil 3 (Co3);
The converter (22) obtains a wear detection voltage (VLa) by taking the difference between the voltage (VT) related to the coils 1 (Co1) and 2 (Co2) and the voltage (VR) related to the coil 3 (Co3). Further, the present invention is characterized in that the presence or absence of wear of the rail (R) is determined from the wear detection voltage (VLa).
For example, the coil 1 (Co1) and the coil 2 (Co2) of the rail displacement sensor (2) are triangular coils,
The coil 3 (Co3) of the wear sensor (3) is a rectangular coil.

In the rail wear measuring method of the present invention, a high frequency current is supplied to each of the coils 1 (Co1) and 2 (Co2) of the rail displacement sensor (2) and the coil 3 (Co3) of the wear sensor (3), An eddy current is generated on the surface of (R). Since the impedance of each coil changes due to the eddy current, a DC voltage signal corresponding to the change is output. The two coils of the coil 1 (Co1) and the coil 2 (Co2) of the rail displacement sensor (2) are disposed to face each other in the lateral displacement direction with respect to the longitudinal direction of the rail (R). When one of (Co1) or coil 2 (Co2) moves in a direction approaching the rail (R), the other coil (Co1 or Co2) moves away. For this reason, the output signal of the coil 1 (Co1) and the output signal of the coil 2 (Co2) change in characteristic opposite directions with the center (RC) of the rail (R) as the axis of symmetry.
These output signals are amplified and taken out as output signals. This signal is subjected to arithmetic processing (height correction and linearization between the rail (R) and the coil 1 (Co1) and the coil 2 (Co2), whereby the coil 1 (Co1) with respect to the center (RC) of the rail (R). The displacement (displacement) of the rail (R) can be detected by taking out as a linear output signal with respect to the lateral displacement (x) of the coil 2 (Co2).

On the other hand, the coil 3 (Co3) of the wear sensor (3) measures the distance between the rail (R) and the wear sensor (3) (coil 3 (Co3)). This means that the output signal of 3 (Co3) has changed and that portion has been worn. These output signals are amplified and taken out as output signals. This signal is subjected to arithmetic processing (height correction / linearization between the rail (R) and the wear sensor (3) to obtain a linear output signal as the wear amount of the rail (R). Thereby, the wear amount (La) of the rail (R) can be detected.
Further, the wear detection voltage is obtained by taking the difference between the voltage (VT) relating to the coils 1 (Co1) and 2 (Co2) of the rail displacement sensor (2) and the voltage (VR) relating to the coil 3 (Co3) of the wear sensor (3). (VLa) is obtained. Whether the rail (R) is worn or not can be determined from the wear detection voltage (VLa).

In the rail wear detection device of the present invention, the eddy current sensor (1) includes the rail displacement sensor (2) and the wear sensor (3), so the coil 1 (Co1) and the rail displacement sensor (2) The rail displacement is measured with the coil 2 (Co2), and the wear is measured with the coil 3 (Co3) of the wear sensor (3). The displacement of the rail (R) and the amount of wear can be detected by calculating the output signal output from each coil by the converter (22). As in the past, it is possible to omit the troublesome work performed manually by a measuring instrument such as a rail wear ruler.
The rail wear detection device of the present invention can be mounted on a track inspection vehicle to measure both the rail displacement and the rail wear during traveling.

It is a schematic front view of the rail explaining the rail wear measuring method using the eddy current type sensor of Example 1. FIG. It is a schematic plan view of the rail explaining the rail wear measuring method using the eddy current type sensor of Example 1. FIG. It is a schematic side view of the rail explaining the rail abrasion measuring method using the eddy current type sensor of Example 1. It is explanatory drawing which shows the state which measures the rail with wear with the coil 1 and the coil 2 of a rail displacement sensor, (a) is the state measured with the coil 1, (b) is the state measured with the coil 2. It is a circuit diagram which shows an example of the output circuit of the coil 1 which comprises a rail displacement sensor. It is a flowchart which shows the abrasion detection method of this invention. It is a graph which shows the output voltage characteristic of the rail measured with the rail displacement sensor of this invention, (a) is the case of a rail without wear, (b) is the case of a rail with wear. It is a graph which shows the characteristic of the output voltage of coil 1 and coil 2, and displacement x. It is a graph which shows the displacement-corrected output voltage Vo'-lift-off z characteristic when the coil 1 and the coil 2 of the rail displacement sensor are used. It is a graph which shows the output voltage characteristic which carried out displacement correction when facing a rail without wear, (a) is an approximate line of a rail without wear, (b) is a linearization voltage VT-lift-off z characteristic by a rail displacement sensor. is there. It is a graph which shows the output voltage characteristic of the rail measured with the coil 3 of the wear sensor, (a) is the case of a rail without wear, (b) is the case of a rail with wear. It is a graph which shows the output voltage Vo'-lift-off z characteristic which carried out displacement correction of the rail wear sensor at the time of using rectangular coil 3 of a wear sensor. It is a graph which shows the displacement output voltage Vo'-lift-off z characteristic after x = 0mm, (a) shows an approximate line of a rail without wear, and (b) shows reversal voltage VR-lift-off z characteristic. It is a graph which shows the output voltage VLa-wear amount La characteristic depending on wear amount La. It is a graph which shows the wear detection voltage VLa and the wear amount La characteristic. It is a schematic block diagram of the rail abrasion detection apparatus using an eddy current type sensor.

  The present invention relates to a rail wear measuring method using an eddy current type sensor that measures displacement and wear of a rail by causing a current to flow through a coil to generate an eddy current in the rail and outputting an impedance change as an output voltage, and a method thereof. It is a measuring device.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<Configuration of rail wear measurement method>
FIG. 1 is a schematic front view of a rail for explaining a rail wear measuring method using the eddy current sensor according to the first embodiment. FIG. 2 is a schematic plan view of a rail for explaining a rail wear measuring method using the eddy current sensor according to the first embodiment. FIG. 3 is a schematic side view of the rail for explaining the rail wear measuring method using the eddy current type sensor of the first embodiment. FIGS. 4A and 4B are explanatory views showing a state in which the rail with wear is measured by the coil 1 and the coil 2 of the rail displacement sensor. FIG. 4A is a state in which the coil 1 is measured, and FIG. is there.
In the rail wear measuring method using the eddy current type sensor of the present invention, an eddy current type sensor 1 including a rail displacement sensor 2 and a wear sensor 3 is used. In addition to the coil for measuring the rail displacement by the rail displacement sensor 2, the coil for the wear sensor 3 for measuring the wear is used together, and the measurement result is processed to measure the rail displacement and the rail wear quickly and accurately. Is the method. The eddy current sensor 1 is mounted on a track inspection vehicle and measures rail displacement and rail wear while traveling.

In the rail wear measuring method of the present invention, a high frequency current is supplied to each of the coils 1 (Co1) and 2 (Co2) of the rail displacement sensor 2 and the coil 3 (Co3) of the wear sensor 3 so as to be applied to the surface of the rail R. Generate eddy currents. An impedance change that changes depending on the displacement x and the lift-off z of the rail R is output as the output voltage Vo, and this output voltage Vo is measured. At this time, as shown in FIG. 1, when measuring the rail displacement, the rail displacement x = 0 mm is adjusted so that the impedances of the coil 1 (Co1) and the coil 2 (Co2) coincide. The lift-off z = 25 mm is used as a reference. Needless to say, these values are not limitative.
These output signals are amplified and taken out as output signals. This signal is processed (height correction / linearization between the rail R and the rail displacement sensor 2).

  As shown in the plan view of FIG. 2, the coil 1 (Co1) and the coil 2 (Co2) of the rail displacement sensor 2 are arranged to face each other in the lateral displacement direction with respect to the longitudinal direction of the rail R. When one of the coil 1 (Co1) or the coil 2 (Co2) moves in the direction approaching the rail R, the other coil (Co1 or Co2) moves away. For this reason, the output signal of the coil 1 (C1) and the output signal of the coil 2 (Co2) change in characteristic opposite directions with the center RC of the rail R as the axis of symmetry. Therefore, the displacement x of the rail R can be measured by the rail displacement sensor 2 including the coil 1 (Co1) and the coil 2 (Co2).

In the rail wear measurement method of the present invention, the coil 3 (Co3) of the wear sensor 3 is further used to output an impedance change that changes depending on the wear amount La of the rail R as the output voltage Vo. taking measurement. The coil 3 (Co3) of the wear sensor 3 measures the distance between the rail R and the wear sensor 3 (coil 3 (Co3)). When the distance is wide (long), the output signal of the coil 3 (Co3) is Change, meaning that part has been worn. These output signals are amplified and taken out as output signals. This signal is subjected to arithmetic processing (height correction and linearization between the rail R and the wear sensor 3), and is extracted as a linear output signal as the wear amount of the rail R. Thereby, the wear amount La of the rail R can be detected.
In the illustrated example, the number of coils 3 (Co3) formed in one wear sensor 3 is not limited to this one. It is also possible to arrange two pieces so as to sandwich the rail displacement sensor 2. In order to increase the measurement accuracy, it is possible to arrange three or more.

  In particular, in the present invention, the wear detection voltage VLa is obtained by taking the difference between the linearized voltage VT relating to the coils 1 (Co1) and 2 (Co2) of the rail displacement sensor 2 and the reversal voltage VR relating to the coil 3 (Co3) of the wear sensor 3. . Whether or not the rail R is worn can be determined from this wear detection voltage VLa.

<Configuration of rail displacement sensor output circuit>
FIG. 5 is a circuit diagram showing an example of an output circuit of the coil 1 constituting the rail displacement sensor.
The coil 1 (Co1) of the rail displacement sensor 2 has a configuration as shown in FIG. 5, for example. Coil 1 (Co1) is incorporated in the sensor unit, and is configured by a coaxial cable 11 and a rectifier circuit. The coil 1 (Co1) is a series circuit of an inductance Ls and a resistance Rs. The coaxial cable 11 is a system comprising an inductance Lca (H), a resistance Rca (Ω), and a capacitance Cca (F). The rail displacement sensor 2 is supplied from an oscillator through a high-frequency excitation voltage Vi (V) having an excitation angular frequency ω (rad / s) and an additional impedance Za (= 1 / (ωC1)) (Ω) having a current Ic (A). Is done.

The rail displacement sensor 2 outputs a voltage proportional to the distance (gap) from the rail R, and responds from a direct current (distance in a stationary state) to a high frequency. Therefore, the displacement / vibration is measured without contact. Since measurement is possible by generating an eddy current on the surface of the rail R, it is limited to a metal that is a good conductor such as the rail R. In addition, the characteristic changes depending on the specific resistance and magnetic permeability of the rail R, that is, the difference in material. In principle, it does not sense an insulator that does not carry current, so it can be measured without being affected by oil or water.
The other coil 2 (Co2) or the coil 3 (Co3) of the wear sensor 3 has the same configuration.

<Flowchart of wear detection method>
FIG. 6 is a flowchart showing the wear detection method of the present invention.
In the flowchart of the wear detection method shown in FIG. 6, the resistance of the coil depending on the displacement x, the lift-off z and the wear amount La is Rs, and the inductance is Ls. A voltage of EE 10 Vpp was applied from the power source. The excitation frequency of the triangular coils of coil 1 (Co1) and coil 2 (Co2) was f = 450 kHz, and the rectangular coil of coil 3 (Co3) was f = 600 kHz. The output voltage Vo of the rail displacement sensor 2 is a value obtained by measuring the voltage of the capacitor C4.

An electric current is passed through the coil 1 (Co1) and the coil 2 (Co2) to generate magnetic flux, and an eddy current is generated in the rail R. The impedance of each coil (Co1, Co2) is changed by the magnetic flux generated by this eddy current, Since the impedance of (Co1, Co2) changes depending on the displacement x, lift-off z, and wear amount La of the rail (R) to be measured, this impedance change is output as the output voltage Vo and the rail R is measured. Can do.
As shown in FIG. 6, the output voltage (Vo) is measured for the rail displacement sensor 2 (coil 1 (Co1) and coil 2 (Co2)). Next, displacement correction Vo ′ is performed on the measurement result to obtain a linearized voltage VT.
On the other hand, the output voltage (Vo) Vo ′ is measured for the wear sensor 3 (coil 3 (Co3)). Next, displacement correction Vo ′ is performed on the measurement result to obtain a linearized voltage and an inverted voltage VR.

  Thereafter, the wear detection voltage VLa is obtained by taking the difference between the linearized voltage VT related to the rail displacement sensor 2 (coil 1 (Co1) and coil 2 (Co2)) and the voltage VR related to the wear sensor 3 (coil 3 (Co3)). . The wear amount La can be detected from the wear detection voltage VLa to determine the presence or absence of wear. Note that “α” in FIG. 6 is an arbitrary constant (= 19.5) as described later.

<Output voltage characteristics by rail displacement sensor>
7A and 7B are graphs showing the output voltage characteristics of the rail measured by the rail displacement sensor of the present invention. FIG. 7A shows a rail without wear, and FIG. 7B shows a rail with wear.
FIG. 7A shows the rail displacement sensor 2 facing the rail R without wear when the triangular coils (coil 1 (Co1) and coil 2 (Co2)) of the rail displacement sensor 2 of the present invention are used. Output voltage characteristics are shown.
The output voltages Vo of the coil 1 (Co1) and the coil 2 (Co2) coincided with each other at 1% or less at a displacement x = 0 mm. The output voltage Vo was measured in the range of rail displacement x = -30-30 mm and lift-off z = 22-28 mm.

  FIG. 7B shows the rail displacement sensor 2 facing the worn rail R when the triangular coils (coil 1 (Co1) and coil 2 (Co2)) of the rail displacement sensor 2 of the present invention are used. Output voltage characteristics are shown. Compared with the rail R without wear, the voltage coincidence point of the coil 1 (Co1) and the coil 2 (Co2) is displaced by 2.7 mm in the x direction.

FIG. 8 is a graph showing the characteristics of the output voltage and displacement x of the coils 1 and 2.
The output voltage Vo (coil 1) + Vo (coil 2) showed a trigonometric change with respect to the displacement x. For FIG. 7, displacement correction was performed using mathematical formulas 1 and 2 including trigonometric functions.
Here, Vo (coil 1): measured output voltage (V) of coil 1,
Vo (Coil 2): Output voltage actual value (V) of coil 2;
x: displacement (mm),
c, d, e: indicate arbitrary constants.
The values in Table 1 were used for the constants c, d, and e.

FIG. 9 is a graph showing the displacement-corrected output voltage Vo′−lift-off z characteristic when the coil 1 and the coil 2 of the rail displacement sensor are used. 10A and 10B are graphs showing output voltage characteristics corrected for displacement when facing a rail without wear, where FIG. 10A is an approximate line of the rail without wear, and FIG. 10B is a linearized voltage VT-lift-off by a rail displacement sensor. It is a z characteristic.
As shown in FIG. 10A, a quadratic function approximation is performed on the lift-off z-displacement-corrected output voltage Vo ′ characteristic, and the linearized voltage VT is obtained as shown in Equation 3.

<About output voltage characteristics by wear sensor>
FIG. 11 is a graph showing the output voltage characteristics of the rail measured by the coil 3 of the wear sensor, where (a) shows the case of a rail without wear and (b) shows the case of a rail with wear.
FIG. 11A shows the output voltage characteristics of the wear sensor 3 facing the non-wear rail R when the rectangular coil of the wear sensor 3 is used. The output voltage was measured in the range of rail displacement x = -30-30 mm and lift-off z = 22-28 mm.
FIG. 11B shows the output voltage characteristics of the wear sensor 3 facing the rail with wear when a rectangular coil is used. The displacement correction formula for the output voltage of the wear sensor 3 using a rectangular coil is expressed by the following mathematical formula 4. The values in Table 1 were used for the constants c, d, and e.

FIG. 12 is a graph showing the output voltage Vo′-lift-off z characteristic of the rail wear sensor corrected for displacement when the rectangular coil 3 of the wear sensor 3 is used. FIG. 13 is a graph showing the displacement-corrected output voltage Vo′−lift-off z characteristic at x = 0 mm, (a) shows an approximate line of a non-wearing rail, and (b) shows an inverted voltage VR-lift-off z characteristic. .
As shown in FIG. 13A, when the quadratic function is approximated with respect to the output voltage Vo ′ after displacement correction−lift-off z characteristic, Equation 5 is obtained. Using this equation, the inverted voltage VR of the output voltage Vo ′ after displacement correction was obtained.

FIG. 13B shows the reverse voltage VR-lift-off z characteristic.
It is shown that the slope of the Vo′-z characteristic is reversed.

<About wear amount detection method using wear sensor>
FIG. 14 is a graph showing the wear detection voltage VLa-wear amount La characteristic depending on the wear amount La.
The wear detection voltage VLa was calculated using the equation (6). In the rail with wear, the variation depending on the lift-off z and the displacement x was large, and the variation was 29.9% at maximum. This is considered to be caused by a variation occurring at the time of displacement correction. The difference between the output voltage without wear and the output voltage with wear is 3.8 V, and it is considered possible to determine the presence or absence of wear.

<About the output voltage characteristics of the wear sensor>
When the output voltage was measured using the coil 1 (Co1) and the coil 2 (Co2) of the rail displacement sensor 2, the sum of the output voltages of the coil 1 (Co1) and the coil 2 (Co2) changed in a trigonometric function. A displacement correction voltage using the coil 1 (Co1) and the coil 2 (Co2) was obtained by a displacement correction formula including a trigonometric function.
When the output voltage was measured using the coil 3 (Co3) of the wear sensor 3, the characteristic changed in a trigonometric function. A displacement correction voltage using the coil 3 (Co3) was obtained by a displacement correction formula including a trigonometric function.

  The difference between the linearized voltage using the coil 1 (Co1) and the coil 2 (Co2) of the rail displacement sensor 2 and the reverse voltage using the coil 3 (Co3) of the wear sensor 3 was calculated. The difference was 3.8 V, and the maximum variation was 29.9%. In other words, it has become possible to measure rail wear in a track inspection vehicle.

<Relationship between wear detection voltage and wear amount>
FIG. 15 is a graph showing wear detection voltage VLa and wear amount La characteristics.
As shown in FIG. 15, the relationship between the wear detection voltage and the wear amount was that the wear detection voltage VLa increased in proportion to the increase in the wear amount La. The lift-off z was measured at 25 mm.

<Configuration of rail wear detection device>
FIG. 16 is a schematic configuration diagram of a rail wear detection apparatus using an eddy current type sensor.
Example 2 is a rail wear detection device based on a rail wear measurement method. By measuring the displacement and wear of the rail R using the rail wear measurement method in a non-contact manner while running on the track inspection vehicle, it is possible to measure and detect quickly and accurately. Therefore, in the second embodiment, the eddy current type sensor 1 composed of the rail displacement sensor 2 and the wear sensor 3 having the functions as described above is housed in a casing 21, and two of them are set as a bottom surface of the track inspection vehicle. To attach to the rail R. At this time, the rail displacement sensor 2 and the wear sensor 3 are directed toward the rail R. This is for non-contact measurement. This eddy current sensor 1 is connected to a converter 22 in the track inspection vehicle by a coaxial cable 11.

  In this rail wear detection device, the eddy current sensor 1 is mounted on a track inspection vehicle and used. The (coil 1 (Co1) and coil 2 (Co2)) of the rail displacement sensor 2 and the coil 3 (Co3) of the wear sensor 3 cause a high-frequency magnetic field to flow through the rail R to measure. Each coil 1 (Co1), coil 2 (Co2), and coil 3 (Co3) includes an amplifier 23 that amplifies the output signal.

  In the converter 22, the output signals of the coil 1 (Co1) and the coil 2 (Co2) and the output signal of the coil 3 (C3) are processed. The converter 22 obtains the wear detection voltage VLa by taking the difference between the voltage VT related to the coil 1 (Co1) and the coil 2 (CO2) and the voltage VR related to the coil 3 (Co3). Whether or not the rail R is worn is determined from the wear detection voltage VLa.

  In the present invention, a rail displacement sensor 2 (coil 1 (Co1) and coil 2 (Co2)) for measuring rail displacement and a wear sensor 3 (coil 3 (Co3)) for measuring wear are used in combination. As long as the results can be processed to detect rail displacement and rail wear quickly and accurately while running on a track inspection vehicle, the present invention is not limited to the above-described embodiment of the present invention. Of course, various changes can be made without departing from the scope of the invention.

  The present invention is not limited to detection of displacement and wear of rails such as trains, but can be used for measurement and detection of displacement and wear generated in other rails or long metal members.

DESCRIPTION OF SYMBOLS 1 Eddy current type sensor 2 Rail displacement sensor 3 Wear sensor 21 Housing | casing 22 Converter 23 Amplifier Co1 Coil 1
Co2 coil 2
Co3 Coil 3
R rail x rail displacement z rail lift-off La rail wear

Claims (4)

A rail wear measuring method using an eddy current type sensor (1) for passing an electric current through a coil to generate an eddy current in a rail (R) and measuring displacement and wear of the rail (R),
Using a rail displacement sensor (2) having a coil 1 (Co1) and a coil 2 (Co2), an impedance change that changes depending on the displacement (x) and liftoff (z) of the rail (R) is output voltage ( Vo), and the displacement (x) of the rail (R) is detected by measuring the output voltage (Vo).
For the output voltage (Vo) measured by the coil 1 (Co1) and the coil 2 (Co2), displacement correction and linearization are performed,
Using a wear sensor (3) having a coil 3 (Co3), an impedance change that changes depending on the wear amount (La) of the rail (R) is output as an output voltage (Vo). ) To detect the amount of wear (La) of the rail (R),
The output voltage (Vo) measured by the coil 3 (Co3) is subjected to displacement correction and linearization,
The wear detection voltage (VLa) is obtained by taking the difference between the voltage (VT) related to the coil 1 (Co1) and the coil 2 (Co2) and the voltage (VR) related to the coil 3 (Co3), and this wear detection voltage (VLa). The rail wear measuring method using an eddy current type sensor characterized by determining whether or not the rail (R) is worn.   Coil 1 (Co1) and coil 2 (Co2) of the rail displacement sensor (2) are measured by being arranged opposite to each other in the lateral displacement direction with respect to the longitudinal direction of the rail (R). A rail wear measuring method using the eddy current sensor according to claim 1. A rail wear detector using an eddy current type sensor that measures the displacement and wear of the rail (R) in a non-contact manner while running on a track inspection vehicle,
A rail displacement sensor (2) comprising a coil 1 (Co1) and a coil 2 (Co2) for generating a high-frequency magnetic field by flowing a high-frequency current through the rail (R) for measuring the displacement of the rail (R). ,
A high-frequency magnetic field is generated by supplying a high-frequency current to the rail (R) for measuring wear of the rail (R) provided at a position adjacent to the coil 1 (Co1) and the coil 2 (Co2). A wear sensor (3) comprising a coil 3 (Co3)
An amplifier (23) for amplifying the output signals of the coils 1 (Co1) and 2 (Co2), an amplifier (23) for amplifying the output signals of the coil 3 (Co3),
A converter (22) for computing the output signals of the coil 1 (Co1) and coil 2 (Co2) and the output signal of the coil 3 (Co3);
The converter (22) obtains a wear detection voltage (VLa) by taking the difference between the voltage (VT) related to the coils 1 (Co1) and 2 (Co2) and the voltage (VR) related to the coil 3 (Co3). A rail wear detection device using an eddy current sensor, characterized in that the wear of the rail (R) is determined from the wear detection voltage (VLa). The coil 1 (Co1) and the coil 2 (Co2) of the rail displacement sensor (2) are triangular coils.
The rail wear detection device using an eddy current sensor according to claim 3, wherein the coil 3 (Co3) of the wear sensor (3) is a rectangular coil.