JP2004314823A - Contacting resistance measuring method for grounding brush - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method to continuously measure the contacting resistance of a grounding brush when a railroad car is running which is equipped with a trucks of wheel independent drive type or with an inter-track variable trucks. <P>SOLUTION: According to the contacting resistance measuring method, the ground line between a terminal table and the grounding brush G is opened and a certain voltage is impressed between the grounding brushes Ga and Gb when the railroad car runs. The resistance between the grounding brushes is determined by measuring the voltage and current between the grounding brushes Ga and Gb. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a railway vehicle including a bogie having integrally formed wheels and a plurality of grounding brushes provided in sliding contact with a rotating portion supported on an axle portion via a bearing or a sliding surface. The present invention relates to a method for measuring the contact resistance of a ground brush during running.
[0002]
BACKGROUND OF THE INVENTION
A bogie of a railway vehicle generally used in Japan has a structure in which wheels and axles are integrated. Both the wheel and the axle are made of a good conductor metal such as iron. For this reason, the impedance of the axle when configuring the track short circuit is generally regarded as substantially constant.
[0003]
FIG. 4 is a diagram for explaining axle impedance of a conventional bogie in which wheels and an axle are integrated. In FIG. 4, the dotted line indicates the path of the track short-circuit current. The track short circuit is performed via the contact resistances Z1 and Z2 between the rail and the wheel, and the axle impedance Zj. However, the contact resistances Z1 and Z2 between the rails and wheels are determined by the weather during traveling (for example, whether it is sunny or rainy), the state of the rails (for example, the presence or absence of inclusions such as rust and fallen leaves, etc.), It changes depending on the inner rail side or outer rail side, or on the branching rail at the time) and does not take a fixed value. For this reason, the short circuit state is usually determined from the axle impedance Zj at the time of stop and the track circuit state at the time of traveling. Here, since the wheel and the axle have an integral structure made of a good conductor metal, the impedance Zj of the axle is generally regarded as substantially constant.
[0004]
By the way, as the bogies currently being developed, there are bogies equipped with a wheel-integrated main motor of each wheel independent drive system, bogies of a variable gauge train for traveling on tracks with different gauges, and the like.
[0005]
In a bogie equipped with such a wheel-independent electric motor of each wheel independent type or a bogie of a variable rail-to-rail train, the wheel and axle are not integrated, but the wheel is rotatable via a bearing or the like. The structure is supported by the axle. For this reason, for example, according to the independent wheel system of the outer rotor type each wheel drive system, with respect to the stator fixed to the axle, the wheel is rotatable integrally with the rotor, while the wheel and the axle are Are not electrically connected, the right and left wheels and the axle cannot be regarded as an integral good conductor.
[0006]
FIG. 5 is a schematic view of a main part relating to axle impedance of a bogie of a wheel independent drive system. The left and right wheels W1, W2 are rotatably supported by the axle SH via bearings (not shown) and lock mechanisms (not shown). In addition, current collecting rings S1 and S2 are integrally formed on the left and right wheels W1 and W2, respectively, and ground brushes G1 and G2 abut on outer peripheral surfaces of the current collecting rings S1 and S2. The wheels W1 and W2 and the current collecting rings S1 and S2 are rotating parts, whereas the ground brushes G1 and G2 are fixed parts that slide on the outer peripheral surface as the current collecting rings S1 and S2 rotate. The ground brushes G1, G2 are connected to the terminal block T by ground lines L1, L2, respectively. In some cases, the ground brushes G1 and G2 are directly connected by a line (electric wire) without using the terminal block T.
[0007]
The wheels W1 and W2, the current collecting rings S1 and S2, the ground brushes G1 and G2, the ground lines L1 and L2, and the terminal block T have the following main functions and sub functions. That is, the main function is to configure a grounding circuit for returning (grounding) power supplied to the main motor and the like via the pantograph to the rail. A secondary function is a function that constitutes a track short circuit.
[0008]
In FIG. 5, the path of the track short-circuit current is indicated by a dotted line. In the axle impedance Zj in FIG. 5, the wheels W1, W2 and the current collecting rings S1, S2 are both metal and are integrally formed, so that the impedance is a substantially constant value. The impedance between the ground brushes G1 and G2 via the ground lines L1 and L2 and the terminal block T is a fixed value even during traveling. For this reason, what may fluctuate during traveling are the contact resistances Zg1 and Zg2 between the grounding brushes G1 and G2 and the current collecting rings S1 and S2 (in this specification, the contact resistances are referred to as “grounding resistance”. Brush contact resistance ").
[0009]
In addition, the above-mentioned problem of each wheel independent drive method is the same also in the variable gauge truck. In other words, in the case of a variable-gauge trolley, it is necessary to slide the wheels in the axle direction with respect to the axle, and in order to facilitate smooth sliding on the sliding surface, as well as bearings on this sliding surface. Normally, oil is applied and the vehicle is almost insulated during running. For this reason, similarly to the above-described wheel-independent drive system, the axle impedance includes the contact resistance of the ground brush that may vary during traveling.
[0010]
By the way, in order to put into practical use a railway vehicle equipped with a bogie of each wheel independent drive system or a variable bogie between rails, it is necessary to perform a running test for running on a track actually used. Testing signals using track circuits is one of the most important tests. For this reason, it is a problem whether or not the track short-circuit is reliably performed by the axle impedance Zj. That is, in the running test, not only the contact resistance between the ground brush and the current collecting ring, but also the contact resistance between the rail and the wheel, and the change in the contact / contact state of the ground brush due to an impact during running are taken into account. . Here, if the shape of the wheel tread is the same, the contact resistance between the rail and the wheel is basically the same as the conventional one. Therefore, the largest factor that determines the axle impedance Zj during running is the ground brush. The point is how much the contact resistance is.
[0011]
However, the trolley of each wheel independent drive system and the trolley of the variable gauge between rails are in the research and development stage and have not been put to practical use. For this reason, at present, a method of continuously measuring the contact resistance of the grounding brush during running of the train has not been proposed.
It should be noted that there is no documented invention to be described which describes the method for measuring the contact resistance of the grounding brush when the vehicle is currently running.
[0012]
[Problems to be solved by the invention]
It is an object of the present invention to realize a method for continuously measuring the contact resistance of a ground brush during traveling of a railway vehicle equipped with a bogie of a wheel-independent drive type or a variable bogie between rails.
[0013]
[Means for Solving the Problems]
In order to solve the above problems, the invention described in claim 1 is
It has wheels integrally formed, and comes into sliding contact with a rotating part (for example, the current collecting ring S in FIG. 2) supported by an axle (for example, the axle SH in FIG. 2) via a bearing or a sliding surface. A method for measuring the contact resistance of a ground brush when a railway vehicle including a bogie provided with a plurality of ground brushes (for example, ground brushes Ga and Gb in FIG. 2) is running,
An opening step of opening a ground line (for example, the ground line L1 in FIG. 1) connected to the ground brush;
An application step of applying a predetermined voltage between two ground brushes among the open ground brushes (for example, voltage application by the AC power supply P in FIG. 2) during running of the railway vehicle;
A measuring step of measuring a voltage and a current between the ground brushes to which the predetermined voltage is applied (for example, an ammeter A and a voltmeter V in FIG. 2);
And determining the contact resistance of the ground brush from the measured voltage and current.
[0014]
According to the first aspect of the present invention, the contact resistance of the grounding brush can be continuously obtained while the railway vehicle is running. Therefore, the axle impedance can be obtained regardless of the weather at the time of traveling, the state of the traveling rail, the traveling place, and the like. Further, it is possible to specifically design and adjust the urging force (pressing force) of the ground brush against the collector ring, the contact area of the ground brush, and the like.
[0015]
According to a second aspect of the present invention, in the method for measuring a contact resistance of a ground brush according to the first aspect,
The plurality of ground brushes include at least two ground brushes having the same sliding locus with respect to the rotating part (for example, the current collecting ring S in FIG. 2),
The applying step may be a step of applying the predetermined voltage between ground brushes having the same sliding locus.
[0016]
According to the second aspect of the present invention, since the sliding locus of the two ground brushes for applying the predetermined voltage is the same, the contact resistance between one ground brush and the rotating part and the other ground brush and the rotating ground are different. The contact resistance between the parts can be regarded as substantially the same. Therefore, the contact resistance for one ground brush can be easily obtained.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Note that, as an embodiment, a description will be given by taking a truck of each wheel independent drive system as an example, but the present invention is not necessarily required to be a truck equipped with an integrated wheel type electric motor, such as a variable gauge between trucks. The present invention can be applied to any bogie as long as it is a bogie in which the wheel (rotating part) and the axle are not integrated.
[0018]
FIG. 1 is a schematic view of a main part relating to axle impedance of one shaft of a bogie of each wheel independent drive system, and the same parts as those in FIG. 5 of the related art are denoted by the same reference numerals. FIG. 2 is a diagram illustrating a configuration of a test circuit (hereinafter, simply referred to as a “test circuit”) for measuring the contact resistance of the ground brush, and illustrates a current collector ring S and an axle SH in a longitudinal section. For the sake of simplicity, bearings and the like are not shown between the current collecting ring S and the axle SH in FIG. 2, but in actuality, the axle SH is collected by interposing a bearing such as a tapered roller bearing. A sliding surface for supporting the electric ring W is formed.
In the following description, a case where the contact resistance of the ground brush G1 (G) on the left side in FIG. 1 is measured will be described.
[0019]
The grounding brush G1 on the left side in FIG. 1 is composed of a pair of grounding brushes (hereinafter, referred to as a “grounding brush set” when a pair of grounding brushes is shown) as shown in FIG. During traveling, each ground brush is electrically short-circuited to the terminal block T by the ground cable L (the ground brush G2 on the right side in FIG. 1 has the same configuration).
[0020]
The grounding brushes Ga and Gb constituting the grounding brush set G are arranged at the same position in the axle direction and at a predetermined distance on the outer peripheral surface of the current collecting ring S. Therefore, the ground brushes Ga and Gb slide on the outer peripheral surface of the current collecting ring S which rotates integrally with the wheel W, and the sliding locus thereof becomes the same locus. That is, since the portion of the current collecting ring S with which the ground brushes Ga and Gb are in contact is the same, the contact resistance between the ground brush Ga and the current collecting ring S and the contact resistance between the ground brush Gb and the current collecting ring S are reduced. Can be regarded as substantially the same.
[0021]
Next, a method of measuring the contact resistance of the ground brush will be described. First, the conductive path between the ground brush set G to be measured and the terminal block T is opened. Specifically, for example, as shown in FIG. 1, the process is performed by removing the ground cable L1 from the terminal block T. Next, a predetermined AC power source P is connected between the ground brushes Ga and Gb via a current limiting resistor R. As a result, a current path from the power supply P → ground brush Ga → collector ring S → ground brush Gb → current limiting resistor R → power supply P is formed, and a test circuit is configured. Next, a predetermined AC voltage is applied by the AC power supply P during running of the train (during test running). The frequency and voltage of the alternating current to be applied may be changed as appropriate. After the AC voltage is applied by the AC power supply P, the current flowing through the test circuit and the voltage between the ground brushes Ga and Gb are measured by the ammeter A and the voltmeter V, respectively.
[0022]
Then, the contact resistance between the ground brush and the current collecting ring is obtained based on the measured current and voltage. In addition, since the contact resistance between each of the ground brushes Ga and Gb and the collector ring S can be regarded as substantially the same, the contact resistance between the collector brush S and one of the ground brush Ga and the ground brush Gb should also be determined. Can be.
[0023]
By configuring this test circuit during a test run of a railway vehicle, the contact resistance of the ground brush can be determined continuously. Then, the axle impedance can be obtained regardless of the weather at the time of traveling, the state of the traveling rail, the traveling place, and the like. Also, make specific designs and adjustments for practical use of the railway vehicle, such as changing the urging force (pressing force) of the ground brush against the collector ring or changing the contact area of the ground brush. Can be.
[0024]
Although the embodiments have been described above, the present invention is not limited to the contents of the above embodiments, and can be appropriately changed without departing from the gist of the present invention. For example, the grounding brush set G has been described as being configured by two grounding brushes, but may be three or more. In this case, the same operation and effect as those of the above-described embodiment can be obtained by configuring a test circuit between any two ground brushes having the same sliding locus.
[0025]
As shown in FIG. 3, the ground brushes Ga and Gb are pressed against the current collecting ring S by metal brush holders Ha and Hb in which springs (not shown) and the like are provided, respectively. The brush holder Hb may be connected by an arc-shaped metal body. The ground brushes Ga and Gb and the brush holders Ha and Hb are electrically integrated (short-circuited), and the resistance is reduced as much as possible to fulfill the role of the main function of the ground brush. However, in configuring the test circuit, it is necessary to form a current path from the ground brush Ga → the current collecting ring S → the ground brush Gb. For this reason, at least at the time of a test run, a step of insulating the ground brushes Ga and Gb from the brush holders Ha and Hb is required. Specifically, it can be realized by laying an insulating rubber on the inner surfaces of the brush holders Ha and Hb.
[0026]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the contact resistance of a grounding brush can be calculated | required continuously during running of a railroad vehicle. Therefore, the axle impedance can be obtained regardless of the weather at the time of traveling, the state of the traveling rail, the traveling place, and the like. Further, specific design and adjustment of the urging force (pressing force) of the ground brush against the collector ring and the contact area of the ground brush can be achieved.
[Brief description of the drawings]
FIG. 1 is a schematic view of a main part relating to axle impedance of one axle of a bogie of a wheel independent drive system.
FIG. 2 is a diagram showing a configuration of a test circuit for measuring contact resistance of a ground brush.
FIG. 3 is a view for explaining a state in which the brush holder is connected by an arc-shaped metal body.
FIG. 4 is a diagram for explaining axle impedance of a conventional bogie having a wheel and an axle integrated with each other.
FIG. 5 is a schematic diagram of a main part relating to axle impedance in a bogie of a wheel independent drive system.
[Explanation of symbols]
T Terminal block L Ground line G Ground line group Ga Ground line Gb Ground line S Collector ring P AC power supply A Ammeter V Voltmeter R Current limiting resistor SH Axle

Claims (2)

Grounding at the time of traveling of a railway vehicle equipped with a bogie provided with a plurality of grounding brushes having wheels integrally formed and having a plurality of grounding brushes slidably contacting a rotating portion supported on an axle portion via a bearing or a sliding surface. A method for measuring the contact resistance of a brush,
An opening step of opening a ground line connected to the ground brush,
An application step of applying a predetermined voltage between two ground brushes of the open ground brushes during running of the railway vehicle;
A measuring step of measuring a voltage and a current between the ground brushes to which the predetermined voltage is applied,
And determining the contact resistance of the ground brush from the measured voltage and current. The plurality of ground brushes include at least two ground brushes having the same sliding locus with respect to the rotating unit,
The method according to claim 1, wherein the applying step is a step of applying the predetermined voltage between ground brushes having the same sliding locus.

Images