Method and system for monitoring a rail segment

Abstract

The invention relates to a method for monitoring the presence or absence of at least one component of a rail vehicle (4) traveling on a rail (3a, 3b) on a rail section (2), said method comprising: obtaining a first measurement signal (6a) of a first sensor (8a) located at a starting end (7) of the rail section (2); obtaining a second measurement signal (6b) of a second sensor (8b) located at a termination end (9) of the track section (2); evaluating the first measurement signal (6a) and the second measurement signal (6b) for recording and counting incoming metal bodies and for recording and counting outgoing metal bodies, the axles or wheels (10a, 10b, 10c, 10d) and possibly present brakes (11a, 11b) being detected as metal bodies; the presence or absence of components of the rail vehicle (4) on the rail section (2) is concluded on the basis of the recording and counting results.

Description

Technical Field

[0001] The present invention relates to a method and a system for monitoring a track segment for the presence or absence of at least one component of a rail vehicle travelling on the track. Background Art

[0002] Traditionally, track sections are monitored using so-called axle counters via counting points (sensors) with the aid of detection wheels.

[0003] However, it has been found that conventional methods and systems for monitoring track segments do not provide reliable results in all situations and for all configurations of rail vehicles, thereby resulting in erroneous counts that reduce the usefulness of track vacancy reports.

[0004] The technical problem to be solved by the present invention is therefore to provide a method and a system for monitoring a track segment, wherein the reliability of the method is increased and untimely or permanent occupation of the track segment can be avoided. The technical problem to be solved by the present invention is, in particular, to propose a method and a system for monitoring a track segment, which method and system also provide reliable results for rail vehicles, which also have magnetic rail brakes, in particular between the wheels.

[0005] The technical problem is solved by the technical solution of the independent claim. The dependent claims describe advantageous embodiments. Summary of the invention

[0006] According to an embodiment of the present invention, a method for monitoring the presence or absence of at least one component of a rail vehicle traveling on the track on a track segment is provided, wherein the method comprises: obtaining a first measurement signal of a first sensor located at the starting end of the track segment; obtaining a second measurement signal of a second sensor located at the ending end of the track segment (if necessary, additional sensors for defining the track segment boundary are also provided in switches and crossing track segments); evaluating the first measurement signal and the second measurement signal for recording and counting incoming metal bodies and for recording and counting outgoing metal bodies, wherein axles or wheels and possibly existing brakes are detected as metal bodies; and inferring the presence or absence of components of the rail vehicle on the track segment based on the recording and counting results.

[0007] The method can be implemented by software and hardware. For example, according to an embodiment of the present invention, the method can be executed or controlled by a system for monitoring a track segment.

[0008] The track segments monitored typically have a length of, for example, between 30 m (possibly shorter, but the length of the track segment should always be greater than the maximum axle spacing of the vehicles so that the vehicles do not cross the segment) to almost infinity. Rail vehicles can, for example, be used to transport passengers and / or goods.

[0009] Both the first sensor (the sensor for counting the incoming track segments) and the second sensor (the sensor for counting the outgoing track segments) can be used to detect metal blocks or bodies located above or below the upper edge of the track or within the sensor detection range. The sensors can include conventional sensors, in particular axle counting sensors. The sensors must also be able to detect the direction of travel.

[0010] For monitoring the side line, a single sensor is sufficient to detect vehicles entering and leaving. In this case, the first sensor is identical to the second sensor.

[0011] In other embodiments, more than two sensors may be installed at different locations on the track segment and their measurements may be used.

[0012] The rail vehicle may move in a direction from the starting end to the ending end of the track segment. The rail vehicle does not necessarily have to travel through the entire track segment, but may, for example, stop before the track segment is completely passed, or change the direction of travel within the track segment if necessary. According to other embodiments of the present invention, the rail vehicle may completely pass through the track segment, so that the first sensor and the second sensor (and / or further sensors, such as sensors at switches or intersections) pass the rail vehicle or parts of the rail vehicle at the same time. For example, the length of the rail vehicle may be between 10m and 500m. Embodiments of the present invention may also detect the presence or absence of a complete rail vehicle on a track segment.

[0013] The measurement signal may be received from the first sensor or the second sensor via a cable connection, an optical connection or wirelessly.The measurement signal may comprise an analog measurement signal, such as an induced voltage generated in the sensor due to a passing metal body.

[0014] The evaluation of the first measurement signal and the second measurement signal may, for example, include a comparison with one or more threshold values.

[0015] A metal body, in particular a ferromagnetic block or body, which is a component of the rail vehicle and which passes over the first sensor into the track section can be understood as a metal body that moves in. All metal parts of the rail vehicle, in particular ferromagnetic parts, can be understood as metal bodies that move out if they move beyond the second sensor and thus beyond the track section.

[0016] Traditionally, only the wheels of a rail vehicle are recorded. However, according to an embodiment of the invention, any brakes that may be present are also detected, in particular brakes between two wheels or between two axles of a rail vehicle. Brakes can be used for braking in certain driving situations or under certain external environmental conditions.

[0017] The embodiments of the present invention do not require knowledge of the presence of such brakes on the rail vehicle. However, if these brakes are present when the assessment is made, they can also be detected without needing to know their presence.

[0018] According to one embodiment of the invention, at least one counter (or register or storage location) can be provided, which counter counts, for example, the number of metal bodies driving in and the number of metal bodies driving out. Thus, it is not necessary to count the number of metal bodies driving in or out. At the end of the evaluation or measuring time, it is only necessary to read out the state of the at least one counter in order to determine the presence or absence of a component of the rail vehicle in the track segment.

[0019] According to another embodiment, the number of metal bodies driving out and the number of metal bodies driving in can actually be counted, in particular in two different counters (or registers or storage locations). After comparing the counter readings of the input or output sensors, an evaluation can be performed (generating an idle report). If the result of the comparison is that the number of metal bodies entering and leaving is the same, it means that the rail vehicle has left the track segment. In the case of active magnetic rail brakes, the saturation state of the track is detected instead of the metal body.

[0020] Embodiments of the present invention do not require knowledge of the number of axles or wheels and / or the number of brakes that may be present on a rail vehicle. Thus, embodiments of the present invention can support rail vehicles of different configurations, as their presence or absence can be reliably determined.

[0021] According to one embodiment of the invention, the method provides that the metal body comprises elements of a rail vehicle which are arranged vertically close to the rail, in particular wheels and / or axles and / or brakes of the rail vehicle.

[0022] Thus, the method can record the wheels or axles and brakes of a rail vehicle when entering and exiting a monitored track section. The method can therefore be applied to different types of rail vehicles.

[0023] According to one embodiment of the present invention, the method stipulates that the evaluation of the first measurement signal and the second measurement signal includes: determining a first number of first measurement signals that are above an upper threshold or below a lower threshold; determining a second number of second measurement signals that are above an upper threshold or below a lower threshold, wherein the upper threshold is larger than the lower threshold.

[0024] The measurement signal can be, for example, a measurement signal level, in particular a relative voltage (for example relative to a measurement value in the absence of a metal body or a rail vehicle) as a function of time. The upper threshold value and / or the lower threshold value can be determined by determined measurement values ​​of a known metal body or a vehicle of a known configuration or training data, wherein, for example, test measurements can be carried out in which different rail vehicles pass the sensor. For the test measurements, the configuration of the rail vehicle is known with regard to the number of wheels and / or brakes that may be present. The method can thus be implemented by defining only one upper threshold value and one lower threshold value and determining whether the individual measurement signals are above or below the corresponding threshold value. This provides a very simple method for reliable monitoring of track sections.

[0025] According to one embodiment of the invention, the conventionally existing delay of the measurement signal is suppressed below a lower threshold value. Conventionally, the lower threshold value can be used to detect faults when installing the respective sensor, in particular to detect whether the fixing bolts or screws have become loose, thereby causing an unfavorable change in the position of the sensor relative to the rail, such as the sensor falling off the rail. For this purpose, the measurement signal below the lower threshold value is usually suppressed or delayed. According to an embodiment of the invention, this conventional delay is suppressed because the result of the measurement signal being below the lower threshold value is also used to detect metal bodies, in particular for detecting magnetic rail brakes in a reliable manner.

[0026] According to one embodiment of the invention, the method provides that inferring the presence or absence of a rail vehicle comprises: comparing the first number with the second number; and inferring the presence or absence of a component of a rail vehicle on the track segment based on the comparison result.

[0027] When comparing the first number with the second number, it can be determined, for example, whether the number of metal bodies entering the track section is the same as or different from the number of metal bodies leaving the track section. This allows for reliable monitoring.

[0028] According to one embodiment of the present invention, the method further comprises: if the first number is equal to the second number, it is inferred that there are no parts of a rail vehicle on the track segment; and / or if the first number is greater than the second number, it is inferred that there are parts of a rail vehicle on the track segment; and / or if the first number is less than the second number, it is inferred that there is an error.

[0029] Therefore, simple logical queries are sufficient to achieve a reliable diagnosis of the track segment occupancy status.

[0030] According to one specific embodiment of the invention, the method provides that the upper threshold value is selected such that a measurement signal triggered by an inactive brake of the rail vehicle, in particular a magnetic rail brake, or by an axle and a wheel, is above the upper threshold value.

[0031] Thus, by determining that the measurement signal is above the upper threshold value, a wheel or axle and an inactive brake can be reliably detected.

[0032] According to one embodiment of the invention, the method provides that the lower threshold is selected such that a measurement signal triggered by an activated brake of the rail vehicle, in particular a magnetic rail brake, is below the lower threshold and a measurement signal triggered by wheels and axles is above the lower threshold.

[0033] Thus, an activated brake can also be detected by determining whether the measurement signal falls below a lower threshold value.

[0034] Thus, activated brakes and inactivated brakes can be reliably detected or recorded by evaluating the individual measurement signals. The reliability of the method can be improved thereby.

[0035] According to one embodiment of the present invention, the method stipulates that the upper threshold value and / or the lower threshold value are set in such a way that axles and / or wheels and possible magnetic rail brakes in activated and unactivated states are counted or recorded, wherein the rail friction contact surface of the magnetic rail brake (in the unactivated state) has a spacing of 4 mm to 9 mm with the track in particular.

[0036] The magnetic rail brake can be arranged, for example, between two axles or wheels of a rail vehicle, such as a tractor. For braking, the magnetic rail brake can contact the rail surface via the rail friction contact surface so as to produce a braking effect by friction resistance. Embodiments of the present invention can support magnetic rail brakes at a relatively small distance from the rail. This is particularly suitable for short-distance rail vehicles, such as subways, suburban trains or trams.

[0037] According to one embodiment of the invention, the component of the rail vehicle has at least one magnetic rail brake, which is in particular temporarily activated or temporarily deactivated (for example when a measurement signal is detected).

[0038] Conventionally, the existence of magnetic rail brakes can cause false counting, and thus cause the misdiagnosis of the occupancy situation of the track segment. However, since magnetic rail brakes can be reliably recorded or counted together, therefore also support rail vehicles with at least one magnetic rail brake.

[0039] According to one embodiment of the present invention, the method stipulates that when the component of the rail vehicle passes / sweeps over the first sensor, the first measurement signal is continuously measured; when the component of the rail vehicle passes / sweeps over the first sensor, the second measurement signal is also continuously measured.

[0040] The measuring signals can be monitored continuously, but event control is also possible. If the measured value acquired by the sensor does not change within a certain period of time, it is continuously evaluated. This allows inferences to be drawn about the occupancy status of the track section.

[0041] According to one embodiment of the present invention, the first sensor and / or the second sensor is configured as a metal sensor, in particular a counting point of an axle counter system, thereby supporting conventional sensors and simplifying the implementation of the present invention.

[0042] According to one embodiment of the present invention, the first sensor and / or the second sensor includes: an electromagnetic generator coil, which is arranged on one side of the steel rail of the track and is used to generate an alternating magnetic field; an electromagnetic detector coil, which is arranged on the other side of the steel rail of the track and is used to detect the alternating magnetic field by voltage induction, and the voltage particularly represents the measurement signal.

[0043] The generator coil can, for example, generate a (high frequency) alternating magnetic field with a frequency of several kilohertz (e.g. 30 kHz to 1000 kHz). The alternating magnetic field generated by the generator coil can also extend to the area of ​​the detection coil. If a metal body, in particular a ferromagnetic metal body, enters the space between the generator coil and the detection coil (e.g. a wheel of a rail vehicle or a magnetic rail brake), the magnetic field generated by the generator coil will change. As a result, the induced voltage in the receiving coil due to the change in the magnetic field in the detection coil is different from the induced voltage when there is no metal body. For example, the measurement signal can represent the level of the induced voltage, in particular relative to the induced voltage when there is no metal body between the excitation coil and the detection coil (e.g. a ratio), that is, the induced voltage when there is no metal body moving on the surface of the rail.

[0044] According to one embodiment of the present invention, the rail vehicle is a long-distance transportation vehicle or a short-distance transportation vehicle, in particular, a subway, a tram or a suburban railway.

[0045] It should be understood that according to the embodiments of the present invention, features explained, provided or applied to the track segment monitoring method independently or in any combination may also be applied to the track segment monitoring system independently or in any combination, and vice versa.

[0046] According to one embodiment of the present invention, a system for monitoring the presence or absence of at least one component of a rail vehicle traveling on the track on a track segment is provided, wherein the system comprises: an input port, the input port being configured to: obtain a first measurement signal of a first sensor located at a starting end of the track segment; and obtain a second measurement signal of a second sensor located at a terminating end of the track segment; an evaluation module, the evaluation module being configured to: evaluate the first measurement signal and the second measurement signal, for recording and counting incoming metal bodies and for recording and counting outgoing metal bodies, wherein axles or wheels and possibly existing brakes are detected as metal bodies; and infer the presence or absence of components of the rail vehicle on the track segment based on the recording and counting results.

[0047] Embodiments of the invention are explained with reference to the accompanying drawings. The invention is not limited to the embodiments shown or described. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 A schematic diagram showing a system for monitoring a track segment according to an embodiment of the present invention;

[0049] Figure 2 A schematic side view showing a component of a rail vehicle, the portion of which is monitored for presence on a track segment according to an embodiment of the present invention;

[0050] Figure 3 shows a measurement signal and count pulses according to a conventional method;

[0051] Figure 4 shows measurement signals and corresponding count pulses which are detected and evaluated according to one embodiment of the invention;

[0052] Figure 5 Experimental results obtained according to an embodiment of the present invention are shown. DETAILED DESCRIPTION

[0053] Figure 1The system 1 in the invention is used for monitoring a track segment 2 for the presence or absence of at least one component of a rail vehicle 4 travelling on rails 3a, 3b of a track 40, the system comprising input ports 5a, 5b for receiving a first measurement signal 6a from a first sensor 8a located at a starting end 7 of the track segment 2 and a second measurement signal 6b from a second sensor 8b located at a terminal end 9 of the track segment 2. The system 1 further comprises an evaluation module for evaluating the first measurement signal 6a and the second measurement signal 6b in order to record or count metal bodies 10a, 10b, 10c, 10d and 11a, 11b of the rail vehicle 4, wherein the axles or wheels 10a, 10b, 10c, 10d and possibly brakes 11a, 11b are detected as metal bodies. The evaluation module of the system 1 is further configured to draw a conclusion on the presence or absence of a component of the rail vehicle 4 on the track segment 2 based on the recording or counting. The system 1 is configured for executing or controlling a method for monitoring a track segment 2.

[0054] The rail vehicle 4 moves on the two rails 3a, 3b of the track 40 in the direction indicated by the arrow 12. Figure 1 In the illustrated embodiment, the rail vehicle 4 comprises at least one tractor having two pairs of axles 10a, 10b, 10c, 10d, wherein magnetic rail brakes 11a, 11b are respectively installed between every two axles 10a, 10b and 10c, 10d.

[0055] The two rails 3 a , 3 b together with sleepers (not shown) and ballast or a fixed track form a track 40 .

[0056] The sensors 8a, 8b each include, for example, a generator coil 13, which is mounted on one side of the rail 3b and is designed to generate an alternating magnetic field. The sensors 8a, 8b also include an electromagnetic detection coil 14 for detecting the alternating magnetic field by an induced voltage. The measurement signal 6a, 6b can in particular represent a relative (or absolute) induced voltage, which is a portion of the induced voltage generated when no metal body passes through the corresponding sensor 8a, 8b. Thus, the sensors 8a, 8b are configured as metal sensors, which can also be generally referred to as counting points.

[0057] The system 1 further comprises a first sensor 8a and a second sensor 8b.

[0058] Figure 1 4 shows a time point after the wheel axle 10c, 10d and the magnetic rail brake 11b have passed the first sensor 8a. Subsequently, the rail vehicle 4 or the wheel or wheel axle 10a, 10b and the magnetic rail brake 11a also pass the first sensor 8a. In a second time period later, the rail vehicle 4 and in particular the individual wheel axles and the magnetic rail brakes may also pass the second sensor 8b.

[0059] Figure 2 A schematic side view of a rail vehicle 4 moving on rails 3a, 3b is shown. The rail vehicle 4 comprises wheels 10a with axles, wheels 10b and magnetic rail brakes 11a, which are arranged between the wheels or axles 10a and 10b. The wheels 10a, 10b are mounted on a bogie 12a together with the magnetic rail brakes 11a. The distance d (marked as d) between the rail friction contact surface 41 of the magnetic rail brake 11a and the surface of the rail 3b can be, for example, 4 to 9 mm.

[0060] Figure 3 In two coordinate systems, the sensor's measurement signal is represented by the abscissa 15 representing time and the ordinate 16 representing the relative induced voltage in the detection coil 14, or the digitized wheel pulse is represented on the ordinate 17. The analog measurement signals 18, 19 measured in the conventional method are converted into pulses or pulse waveforms 20, 21, respectively. Here, it is only determined whether the individual measurement signals 18, 19 are above the conventional upper switching threshold 22. If the measurement signal 18, 19 is above the conventional upper switching threshold, for example 1.58, the signal is evaluated as a count pulse 20, 21 and is therefore counted as a wheel or axle of the rail vehicle. The conventional lower switching threshold 22a (for example 0.85) is used to detect power failures.

[0061] In regions 23, 24, 25, and 26, the wheels or axles of the rail vehicle are actually present. However, in regions 27 and 28, there are no wheels or axles, but there are brakes. In the measurement range 18, a relatively small signal in the brake region 27 is not evaluated as a wheel pulse, because the measurement signal of the relatively small brake in region 27 (meaning that the metal mass of the brake causes a relative increase in the induced voltage in the detection coil 14) is below the conventional upper threshold 22. However, the measurement signal 19 generated by the relatively large brake in region 28 is higher than the conventional upper threshold 22, resulting in an evaluation as a counting pulse. In this conventional case, the relatively large brake would be mistakenly evaluated as the presence of a wheel, which is marked by lightning. Embodiments of the present invention can avoid this misjudgment by using a brake that causes an increase in the induced voltage in the region of threshold 22.

[0062] According to one embodiment of the present invention, the measurement signal and the resulting pulse count or an example of a counted pulse are as follows: Figure 4 The abscissa 15 represents time, the ordinate 16 represents relative induced voltage, and the ordinate 17 represents count pulses. An upper threshold 30 and a lower threshold 31 are defined in the figure.

[0063] The measurement signal 32 is detected by a rail vehicle having at least two wheel axles 10a, 10b and at least one magnetic rail brake 11a. When the measurement signal 32 is detected, the magnetic rail brake is deactivated, i.e. in a passive state. The measurement signal 32 generated by the presence of the wheels or wheel axles 10a, 10b and the presence of the magnetic rail is above the upper threshold value 30 and is therefore evaluated as a pulse in the count pulse waveform 33.

[0064] Figure 4 The measurement signal curve 34 in shows the measurement signal of the same section of the rail vehicle when the magnetic rail brake 10a is started, that is, activated. In this case, the measurement signal 34 caused by the presence of the axle or wheel 10a, 10b is higher than the upper threshold 30. However, unlike the measurement signal 32, the measurement signal 34 in the region of the activated magnetic rail brake is not higher than the upper threshold 30, but lower than the lower threshold 31. The upper threshold 30 can be, for example, in the range of 1.2 to 1.35 of the relative induced voltage (or relative wheel spacing). The lower threshold 31 can be, for example, in the range of 0.8 to 0.9 of the relative induced voltage (or relative wheel superelevation). Even in the case of an active brake, the evaluation result will also produce a count pulse waveform 35, and one or more wheels or axles 10a, 10b and active brake 11a are counted as count pulses.

[0065] The conventionally observed false counts during axle counting due to the possible presence of magnetic track brakes (activated or deactivated) can thereby be reduced or even completely avoided.

[0066] Magnetic track brakes are of various types, some of which, depending on their design, have a strong influence on the wheel sensors. If the vehicle in question has smaller wheels, reliable operation with the axle counter is generally no longer possible.

[0067] The resulting idle reporting faults traditionally reduce the availability of these systems and ultimately their acceptance. Traditionally, attempts have been made to adjust the sensitivity of the counting points so that the wheels of the rail vehicle are always reliably detected, but the magnetic rail brakes located between the wheels of the chassis are never detected. However, this traditional approach only works if the amplitude of the wheel signal generated by the counting points differs greatly from the amplitude of the brake signal. If the amplitudes of the wheels and brakes are similar, the counting points may not necessarily be set according to the specified requirements. In this case, the use of an axle counter with counting points can lead to availability problems.

[0068] Embodiments of the present invention may include the following details, but they do not constitute essential features of the present invention:

[0069] If all brakes can be counted reliably, the conventional problems can be solved or reduced in the first step. However, the brakes can only be simply measured and counted when they are in a passive state. In this state, the brakes are not powered and move a few millimeters above the upper edge of the rail. Due to the large metal mass, the brakes will have a more or less influence on the counting point, depending on the design of the brakes and their distance from the sensor. By reducing the switching (upper) threshold (compared to the conventional switching threshold), all brakes can be reliably counted. Thus, the upper threshold 30 determined according to one embodiment of the present invention can be smaller than the conventional switching upper threshold.

[0070] If a vehicle with activated brakes passes through the counting point, the signal characteristics change significantly, and conventional signal processing methods become ineffective. Due to the high magnetic field under active brakes, the magnetic properties of the rail change (saturation effect). This reduces the received signal at the counting point and makes it impossible to identify the wheel, at least not in a conventional way.

[0071] To remedy this, one embodiment of the invention proposes to use a lower switching threshold of the counting point. Conventionally, the lower switching threshold of the counting point is used to detect sensor faults. For example, if the fixing bolts on the wheel sensor are loose and the sensor deviates from the rail, this situation must be displayed for safety reasons (fault detection). Falling below the lower threshold usually causes a time delay in the counting point and is not forwarded immediately.

[0072] However, according to one embodiment of the invention, the conventional delay is switched off. Thus, the signal generated by the active brake below the lower threshold is the same as the signal generated by the passive brake above the upper threshold.

[0073] According to an embodiment of the present invention, a method is proposed, which can reliably identify passive (deactivated) and active (activated) brakes, in particular magnetic track brakes, and count wheels, for example.

[0074] Figure 5 In the coordinate system, the measurement signal 36 of a rail vehicle is shown with an abscissa 15 for time and an ordinate 16 for absolute induced voltage or an ordinate 17 for count pulses, which has eight axles or wheels and magnetic rail brakes between them or between the wheel pairs. Figure 5 is active in the first half of Figure 5 The second half is deactivated (passive).

[0075] Also shown is an upper threshold 30 and a lower threshold 31. The upper threshold 30 is at 1.28 and the lower threshold is at 0.85, but these values ​​may be adjusted depending on the application or situation.

[0076] The count pulse waveform 37 clearly shows that the wheel or axle and the magnetic track brake can be reliably identified in both the activated and unactivated states.

[0077] The rail vehicle comprises two carriages, each of which has two bogies, wherein the magnetic rail brake is active in the first carriage and passive in the second carriage. The proposed method or system can be used to reliably monitor the track section.

Claims

1. A method for monitoring the presence or absence of at least one component of a rail vehicle (4) travelling on the track (3a, 3b) on a track segment (2), wherein: The method has: Obtaining a first measurement signal (6a) of a first sensor (8a) located at a starting end (7) of the track segment (2); Obtaining a second measurement signal (6b) from a second sensor (8b) located at a terminal end (9) of the track segment (2); evaluating the first measurement signal (6a) and the second measurement signal (6b) for recording and counting incoming metal bodies and for recording and counting outgoing metal bodies, wherein axles or wheels (10a, 10b, 10c, 10d) and possibly existing brakes (11a, 11b) are detected as metal bodies; Based on the recording and counting results, conclusions are drawn as to the presence or absence of components of a rail vehicle (4) on the track section (2).

2. The method according to the preceding claim, wherein: The metal body comprises elements of a rail vehicle which are arranged vertically close to the rails (3a, 3b), in particular wheels (10a, b, c, d) and / or axles and / or brakes (11a, b) of the rail vehicle.

3. The method according to any one of the preceding claims, wherein: The evaluation of the first measurement signal (6a) and the second measurement signal (6b) comprises: determining a first number of first measurement signals (6a) which are above an upper threshold value (30) or below a lower threshold value (31); determining a second number of second measurement signals (6a) which are above an upper threshold value (30) or below a lower threshold value (31); The upper threshold is greater than the lower threshold.

4. The method according to any one of the preceding claims, wherein: The normally present measurement signal delay is suppressed below the lower threshold value (31).

5. The method according to claim 3 or 4, wherein: Inferences about the presence or absence of rolling stock include: comparing the first amount to the second amount; Based on the comparison result, it is inferred whether a component of a rail vehicle (4) is present or absent on the track section (2).

6. The method according to any one of the preceding claims, wherein: The method further comprises: If the first number is equal to the second number, it is concluded that no parts of a rail vehicle (4) are present on the track segment (2); and / or If the first number is greater than the second number, it is concluded that a component of a rail vehicle (4) is present on the track segment (2); and / or If the first number is smaller than the second number, an error is inferred.

7. The method according to any one of claims 3 to 6, wherein: The upper threshold value (30) is selected in such a way that a measurement signal triggered by an inactive brake of the rail vehicle, in particular a magnetic track brake (11a, b) or by an axle and a wheel, is above the upper threshold value.

8. The method according to any one of claims 3 to 7, wherein: The lower threshold value (31) is selected in such a way that the measurement signals triggered by activated brakes of the rail vehicle, in particular magnetic rail brakes (11a, b), are below the lower threshold value and the measurement signals triggered by the wheels and axles are above the lower threshold value.

9. The method according to any one of claims 3 to 8, wherein: The upper threshold value (30) and / or the lower threshold value (31) are set in such a way that axles and / or wheels (10a, b, c, d) and possibly existing magnetic rail brakes (11a, b) in activated and inactivated states are counted or recorded, wherein the rail friction contact surface (41) of the magnetic rail brake (in the inactivated state) is particularly spaced 4 mm to 9 mm from the track (3b).

10. The method according to any of the preceding claims, wherein: The component of the rail vehicle (4) has at least one magnetic rail brake (11a, b), which is in particular temporarily activated or temporarily deactivated.

11. The method according to any one of the preceding claims, wherein: When the component of the rail vehicle passes / sweeps over the first sensor, the first measurement signal (6a) is continuously acquired; Therein, when the component of the rail vehicle passes / sweeps over the first sensor, the second measurement signal (6b) is continuously detected.

12. The method according to any one of the preceding claims, wherein: The first sensor (8a) and / or the second sensor (8b) are configured as metal sensors, in particular as counting points.

13. The method according to any one of the preceding claims, wherein: The first sensor and / or the second sensor comprises: An electromagnetic generator coil (13) is arranged on one side of a steel rail of the track and is used to generate an alternating magnetic field; An electromagnetic detector coil (14) is arranged on the other side of the rail of the track and is used to detect the alternating magnetic field by induction of a voltage, which in particular represents the measurement signal.

14. The method according to any one of the preceding claims, wherein: The rail vehicle (4) is a long-distance vehicle or a short-distance vehicle, in particular a subway, a tram or a suburban railway.

15. A system for monitoring the presence or absence of at least one component of a rail vehicle (4) travelling on the track (3, 3a) on a track segment (2), wherein: The system has: Input ports (5a, 5b), the input ports are configured as: for obtaining a first measurement signal (6a) of a first sensor (8a) located at the starting end (7) of the track segment (2); for obtaining a second measurement signal (6b) of a second sensor (8b) located at a terminal end (9) of the track segment (2); An evaluation module, wherein the evaluation module is configured as follows: evaluating the first measurement signal (6a) and the second measurement signal (6b) for recording and counting incoming metal bodies and for recording and counting outgoing metal bodies, wherein axles or wheels (10a, b, c, d) and possibly existing brakes (11a, b) are detected as metal bodies; and Based on the recording and counting results, conclusions are drawn as to the presence or absence of components of a rail vehicle (4) on the track section (2).

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