EP2403745B1 - Devices for detecting the occupied state or free state of a track section and method for operating such devices - Google Patents

Description

The present invention relates to a device for detecting the occupancy or free state of a track section with a transmitter for feeding a transmission signal in the form of an AC voltage in the rails of the track section and at least one receiver for receiving a by a transmission of the transmission signal on the rails of the track section caused reception signal,

Such a device is in the form of a trained as track circuit track free reporting device, for example, from the company publication of Siemens AG "FTG S - track vacancy with the audio frequency track circuit FTG S", order no. A19100-V100-B607-V2 known. In this case, a transmitter feeds an AC voltage into the rails of a track section to be monitored. A receiver receives a receive signal in the form of the incoming voltage and evaluates the receive signal. Due to the fact that a rail vehicle traveling through the track section causes a short circuit between the rails of the track section through its axes, the transmission of the transmission signal to the receiver is prevented. This thus makes it possible to detect the busy condition of the track section in question.

In general, in devices for detecting the occupancy or free state of a track section of the type mentioned for safety reasons, the requirement that due to the associated hazards false display of a free state under any circumstances may take place.

Therefore, to avoid interference, for example, it is usually prohibited to route transmit and receive lines of a track circuit within a common cable. Nevertheless, cases are fundamentally conceivable in which undesired influences between transmitter and receiver or between the respective lines to the rails can occur.

This applies both to devices with a transmitter and a receiver and, in particular, to such devices which have a plurality of, as a rule two or three, receivers. For example, in the context of monitoring turnouts or crossings by means of a single track circuit, there is the requirement or necessity to use multiple receivers. The same applies, for example, for the case that the transmission signal is supplied to the track section by means of a so-called center feed, wherein at both ends of the track section in each case a receiver is provided. In such devices having a plurality of receivers, disturbing influences can now also occur, in particular in the event that the electrical lines are guided by a plurality of receivers within a common cable. In such a case, it must be ensured that even if an error occurs, ie, for example, in the case of damage to a cable causing a short circuit or one of the lines routed in the cable, a false clear signal of a track section is reliably avoided. Such an erroneous free message could, for example, arise because due to a short circuit, the high level of a first receive signal of a first receiver in the line of a second receiver whose second receive signal due to an occupancy has a low level coupled.

From the published European patent application EP 0 282 932 A2 is a frequency-modulated track circuit is known, the track circuit receiver has a variable band-pass filter whose center frequency of the frequency of a track circuit encoders of the track circuit is tracked exactly. For this purpose, the output signal of the track circuit generator is fed to the track circuit receiver via a special connection.

The German patent application DE 21 47 773 A1 describes a device for busy signaling a track section, in which an AC voltage fed in at the beginning of the track section is fed to a receiving device, where its phase is compared with the phase of a received AC voltage and a busy shift is derived from a phase shift.

The present invention has for its object to provide a device of the type mentioned in the error, in particular device-side cable fault, can be detected very reliable and at the same time cost.

This object is achieved by a device for detecting the busy or idle state of a track section with a transmitter for feeding a transmission signal in the form of an AC voltage in the rails of the track section, a first receiver for receiving a through the transmission of the transmission signal via the rails of a first part of the track section caused the first reception signal and a second receiver to receive a second reception signal caused by the transmission of the transmission signal via the rails of a second part of the track section, the device for determining the Phase shift between the first receive signal and the second receive signal is formed.

In the solution according to the invention, due to the fact that the device has a transmitter as well as at least two receivers, it is possible to determine the phase shift between the first receive signal and the second receive signal. As a result, an error monitoring of the device, in particular with regard to cable faults, is made possible in a particularly efficient and simple manner. The solution according to the invention is based on the idea that the determination of the phase shift between the signals used makes it possible to detect deviations or disturbances or errors, in particular with regard to the path of the signals.

The device according to the invention is furthermore advantageous in that the evaluation of the phase shift between the received signals can be carried out independently of the processing and evaluation of the actual message information. Therefore, it is possible in particular to distinguish between a defect, such as in the form of a cable fault, and a busy message due to an axle action. It should be noted that with the phase shift between the reception signals, a parameter for error detection is used, which does not apply in the context of the detection of the busy or free state of the track section.

Another advantage is the fact that, in contrast to other conceivable circuits for monitoring the cables or lines in the cable or in the cables advantageously little or no additional circuit parts are needed, so that the inventive Device is particularly cost feasible. Due to the fact that errors can be detected reliably, it is also conceivable that the requirement for a separate routing of transmitting and receiving lines, ie lines leading from the track to the transmitter or receiver, could be omitted. Such a modification made possible in principle by the device according to the invention would lead to a considerable simplification of the cabling of the railway monitoring installation in the form of the device for detecting the occupied or free state of the track section.

It should generally be noted at this point that in the solution according to the invention it is not necessary that the transmitter and the at least two receivers of the device are arranged directly on the track. Thus, said components and means for determining the phase shift between the respective signals, i. For example, a correspondingly designed evaluation device, preferably assigned to the indoor unit, i. For example, installed or housed in a signal box.

Preferably, by means of the device according to the invention, a continuous determination of the phase shift between the received signals. As a result, a permanent functional monitoring of the device is advantageously ensured. Alternatively, however, in principle it is also possible, for example, for the phase shift between the respective signals to be determined only within the framework of the course of a functional test of the device. Thus, a corresponding function test could be performed, for example, every minute, hourly or daily depending on the respective requirements.

It should also be noted that the device according to the invention can be used particularly advantageously in conjunction with audio frequency track circuits, since the signal used to detect the busy or free state of the track section is already an AC signal. In principle, however, it is also possible for the device according to the invention to be used in conjunction with such track circuits which operate with a signal frequency below or above the audible tone range or else according to a direct current principle. In the latter case, the transmission signal in the form of the alternating voltage is a signal which is superimposed on the direct current used for the detection and serves exclusively to monitor the function of the device by determining the phase shift between two reception signals. In such a case, a corresponding transmission signal in the form of an alternating voltage can either be permanently superimposed on the direct current or, for example, additionally fed in at predetermined time intervals merely for functional testing.

According to a particularly preferred embodiment, the inventive device for comparing the phase shift is formed with at least one reference phase shift. This is advantageous because it allows a particularly simple evaluation of the phase shift. Thus, for example, before the device is put into operation, a determination of the phase shift between the received signals in the functional, error-free state of the device for detecting the busy or free state of a track section can be made. This phase shift can then be stored in the form of the reference phase shift, optionally taking into account tolerance values, for example in a memory device of the device. In the later operation of the device Thus, based on a simple comparison of the phase shift with the previously determined reference phase shift, an error can be detected directly and unambiguously.

Regardless of how an error or a fault is detected in the specific case on the basis of the specific phase shift, the affected, associated track section is preferably as a precaution immediately reported as busy in the event of an error to avoid hazards.

As an alternative to the determination of the reference phase shift before commissioning of the track-free reporting device in the form of the device for detecting the busy or free state of a track section, monitoring of the phase shift between the first and the second receive signal would also be possible, for example, by permanently comparing the current one Phase shift takes place with a reference phase shift in the form of the last determined value of the phase shift. This also makes it possible to detect a change in the phase shift immediately and without delay.

Preferably, the device according to the invention can also be developed in such a way that, based on the comparison between the phase shift and the reference phase shift, they are designed to generate an error signal indicating an interference condition. By means of the error signal is thus advantageously the possibility, for example, to alert operating personnel of a signal box directly to the presence of an error.

An error signal indicating a fault condition generated by the apparatus based on the Comparison between the phase shift and the reference phase shift has been generated, can be output in different ways. So it would be conceivable in principle that only a corresponding entry is made in a log file. In a further particularly preferred embodiment, the respective device according to the invention for outputting the error signal is designed in the form of an optical and / or acoustic warning message. As a result, the attention of the operating personnel, ie, for example, the operator of a signal box, is advantageously achieved in a particularly reliable manner.

According to a particularly preferred development of the device according to the invention, the transmitter is designed to feed a modulation signal encoded transmit signal into the rails of the track section and the device for comparing the modulation of at least one of the receive signals formed with the modulation of the transmit signal. In general, the use of a modulation signal encoded transmit signal is advantageous because it increases the insensitivity to interference. By comparing the modulations of the reception signal and the transmission signal while the togetherness of the two signals is verified in a particularly simple manner. This is done without the need for rigid, fixed predetermined, the respective device permanently assigned codings, such as in the form of bit patterns, are required. This advantageously also eliminates corresponding expenses for the configuration of the individual devices, which reduces the manufacturing cost of the device. Furthermore, the assembly is simplified, resulting in addition a time and cost savings. In addition, the project planning of a railway monitoring system is simplified, as there are no assignments of codes or modulations are to be provided to devices and therefore also not to deposit corresponding maps on site plans and data sheets and are observed below. Furthermore, any restrictions with regard to the number and type of modulation used for coding are advantageously eliminated, so that the prerequisite is created that a multiple use of the same modulations within a plant can be ruled out. For this purpose, the device according to the invention can preferably be designed to generate a transmission signal coded by means of any modulation, in particular random-based, modulation. If, when comparing the modulation of the receive signal with the modulation of the transmit signal, a deviation of the modulations is detected, the track section assigned to the device is preferably immediately reported as busy for the purpose of avoiding danger.

Preferably, the device according to the invention can also be developed in such a way that the respective device for transmitting data signals via the rails of the track section is formed on a railway vehicle occupying the track section. This is advantageous, since thus the device can be used in addition to the information transmission to a rail vehicle. This supports, for example, applications in the area of linear train control. A correspondingly further developed device can advantageously be designed such that the transmitter and receiver are connected to the respective track-side feed points, for example in the form of so-called track terminal housing, such that either a transmit signal of a transmitter or a receive signal for either fed into the feed points a receiver can be read or received. Such a known switching is advantageous because the transmission of Data signals to a rail vehicle is only possible as long as the transmitter is in the direction of travel in front of the rail vehicle. The reason for this is that otherwise by a short-circuiting of the rails through the axes of the rail vehicle and the transmission of data signals to a usually arranged in the front region of a rail vehicle receiving device is prevented. In this connection, it should be pointed out that the device according to the invention is also advantageous in that the determination of the phase shift between the two reception signals is possible in the same way regardless of the direction of travel and the position of the rail vehicle in the track section.

The present invention further relates to a method of operating a device for detecting the occupancy or free state of a track section.

With regard to the method, the present invention has the object to provide a method for operating a device for detecting the busy or free state of a track section, which makes it possible to detect errors, especially device-side cable fault, particularly reliable and cost-effective.

This object is achieved by a method for operating a device for detecting the busy or free state of a track section, wherein a transmission signal is fed in the form of an AC voltage in the rails of the track section, a through the transmission of the transmission signal on the rails of a first Part of the track section effected received first received signal, one caused by the transmission of the transmission signal on the rails of a second part of the track section second receive signal is received and the phase shift between the first receive signal and the second receive signal is determined.

The advantages of the method according to the invention essentially correspond to those of the device according to the invention, so that in this regard reference is made to the corresponding explanations above. The same applies to the below-mentioned preferred developments of the method according to the invention, with respect to which reference is likewise made to the corresponding statements in connection with the respective preferred development of the device according to the invention.

Preferably, the inventive method is designed such that the phase shift is compared with at least one reference phase shift.

According to a further particularly preferred embodiment, the method according to the invention is configured in such a way that an error signal indicating a fault condition is generated based on the comparison between the phase shift and the reference phase shift.

Preferably, the inventive method can also run such that the error signal is output in the form of an optical and / or acoustic warning message.

Advantageously, the inventive method is configured such that a coded by a modulation transmission signal is fed into the rails of the track section and the modulation of the receive signal or the modulation of at least one of the receive signals is compared with the modulation of the transmit signal.

According to a further particularly preferred development of the method according to the invention, data signals are transmitted to a rail vehicle occupying the track section via the rails of the track section.

Figur 1

eine schematische Skizze einer Anordnung mit einem Gleisabschnitt sowie einer Vorrichtung mit einem Sender und einem Empfänger,

Figur 2

eine schematische Skizze einer Anordnung mit einem mittengespeisten Gleisabschnitt und einem ersten Ausführungsbeispiel der erfindungsgemäßen Vorrichtung mit einem Sender und zwei Empfängern,

Figur 3

eine schematische Skizze einer Anordnung mit einem Gleisabschnitt in Form einer Weiche und einem zweiten Ausführungsbeispiel der erfindungsgemäßen Vorrichtung mit einem Sender und zwei Empfängern und

Figur 4

in einer schematischen Darstellung zur Verdeutlichung eines Ausführungsbeispiels des erfindungsgemäßen Verfahrens einen Graphen mit einem Sende-Signal sowie zwei Empfangs-Signalen.

In the following the invention will be explained in more detail by means of exemplary embodiments. This shows

FIG. 1

a schematic sketch of an arrangement with a track section and a device with a transmitter and a receiver,

FIG. 2

1 is a schematic sketch of an arrangement with a center-fed track section and a first exemplary embodiment of the device according to the invention with a transmitter and two receivers,

FIG. 3

a schematic sketch of an arrangement with a track section in the form of a switch and a second embodiment of the device according to the invention with a transmitter and two receivers and

FIG. 4

in a schematic representation to illustrate an embodiment of the method according to the invention a graph with a transmit signal and two receive signals.

For the sake of clarity, the same reference numerals are used in the figures for identical or identically acting components.

FIG. 1 shows a schematic sketch of an arrangement with a track section and a device with a transmitter and a receiver. Shown is a device V for detecting the busy or free state of a track section G. The device V has a transmitter S for feeding a transmission signal SIG _S in the form of an AC voltage in the rails F of the track section G. In addition, the device V a receiver E for receiving a caused by the transmission of the transmission signal SIG _S on the rails F of the track section G reception signal SIG _E.

As shown in FIG. 1 an AC voltage of the frequency f1 is fed into the track section G. In order to enable a reliable differentiation of the respective signals, the adjacent track sections are operated with an alternating voltage of different frequency f5 or f3. In the following, it is assumed that the arrangement shown in the figure is an audio frequency track circuit with a plurality of frequencies, in which an AC voltage in the form of a transmission signal SIG _S in the audio frequency range is fed into the tracks F of the track section G.

The device V can be arranged for example in a signal box of a railway installation or a railway monitoring system. This offers the advantage that a particularly high level of reliability is achieved, since mechanical load and climatic influences with respect to the electronic components of the device V have a lower effect than would be the case if these components were accommodated close to the track. In addition, this results in further advantages in terms of availability and maintenance of the device V, ie in particular the transmitter S and the receiver E. By means of the horizontal dot-dash line is in FIG. 1 a corresponding separation between the indoor unit, which is associated with the device V, and the outdoor area, to which the track section G belongs, indicated.

As shown in FIG. 1 are trackside siding housing Gag1, GAG2 disposed, which serve for introducing the injected by the transmitter S respectively provided transmission signal SIG _S respectively for reading out the transmit to the receiver E reception signal SIG _E into or out of the rails F. Usually, the track connection housing GAG1, GAG2 hereby contain no active electronic components, but essentially only a resonant circuit for frequency-selective amplification of the input or output signals of predetermined useful frequency, ie in the case of in FIG. 1 shown track section G of the frequency f1.

In order to allow monitoring of faults or faults, in particular with regard to the cables or lines from the transmitter S to the track connection housing GAG1 or from the track connection housing GAG2 to the receiver E, the device V further comprises an evaluation device AE, which is used to determine the phase shift between that of the Transmitter S transmitted transmit signal SIG _S and received by the receiver E receive signal SIG _E is used. For this purpose, the evaluation device AE receives the transmission signal SIG _S from the transmitter S and the reception signal SIG _E from the receiver E and carries out a preferably signal-technically reliable determination of the phase shift between the two signals SIG _S , SIG _E. In this case, the device V or the evaluation device AE for comparing the determined phase shift formed with at least one reference phase shift. The reference phase shift is preferably the value of the phase shift between the transmit signal SIG _S and the receive signal measured in the error-free state of the system.

Disturbances, for example due to the crosstalk of the signals of adjacent track circuits, for example due to damage to an electrical line, can now advantageously be reliably detected on the basis of the comparison of the phase shift with the reference phase shift. Upon detection of a corresponding error reports the evaluation device AE of the device V, the track section G precaution as occupied and generates an error signal indicating the relevant fault condition. For this purpose, the error signal can be output, for example, in the form of an optical and / or acoustic warning message. Here, advantageously, a reliable distinction between a disturbance, i. a cable error, and a regular free-busy message allows. In addition, the determination of the phase shift and the comparison with the reference phase shift can advantageously be realized in a comparatively low-cost manner, so that little or no additional circuit components are needed, which results in cost savings compared to other conceivable solutions.

It should be emphasized that the illustration in FIG. 1 is only a schematic representation. Thus, in practice, other components may be present or required, which in FIG. 1 are not shown for reasons of clarity. So it is conceivable, for example, that the device V in addition to the transmission of data signals on the rails F of the track section G is formed on a the track section G occupying rail vehicle. In this case, the transmitter S of the device V advantageously has an external drive, by means of which the data signals can be supplied to the transmitter S.

FIG. 2 shows a schematic diagram of an arrangement with a center-fed track section and a first embodiment of the device according to the invention with a transmitter and two receivers. In contrast to the representation of the FIG. 1 is it FIG. 2 thus an arrangement with two receivers E1, E2. In this case, the receivers E1, E2 are each supplied with a receive signal SIG _E or SIG _E2 via the track connection housings GAG1, GAG3. The first receiver E1 serves to receive the first reception signal SIG _E1 caused by the transmission of the transmission signal SIG _S via the travel rails F of a first part of the track section G, the first part of the track section passing through the route between the track connection housings GAG1 and GAG2 is formed. Accordingly, the second receiver E2 serves to receive the second reception signal SIG _E2 caused by the transmission of the transmission signal SIG _S via the travel rails F of a second part of the track section G formed by the route between the track connection housings GAG2 and GAG3.

Based on the in FIG. 2 shown arrangement, a monitoring of the functioning of the device V in the form of the track-free reporting device take place in that the phase shift between the first receive signal SIG _{E1 of} the receiver E1 and the second receive signal SIG _{E2 of} the second receiver E2 is determined. The thus determined phase shift allows reliable detection of interference, especially in the form of cable faults. This is included an arrangement with a transmitter S and a plurality of receivers E1, E2 of particular importance, since in particular in the event that the lines of multiple receivers E1, E2 are guided within a cable, interference by crosstalk or coupling a receive signal in the line of other recipient can be caused. Such disturbances or errors are reliably detected by means of the evaluation device AE of the device V by comparing the phase between the received signals SIG _E1 , SIG _E2 , so that even in the case of lines of several receivers E1, E2, in the same cable be guided, errors or disturbances can be excluded.

If the device has more than two, i. For example, if there were three receivers, the phase shift of a combination or several combinations of the receive signals of the receivers could be determined analogously to the procedure described above.

FIG. 3 shows a schematic diagram of an arrangement with a track section in the form of a switch and a second embodiment of the device according to the invention with a transmitter and two receivers. Similar to the illustration in FIG. 2 this is an arrangement with a device V with a transmitter S and two receivers E1, E2. In the case shown, this is a switch circle, which is used to completely monitor a switch W.

Analogous to in connection with FIG. 2 also described in such an arrangement by determining the phase shift between the receive signals SIG _E1 , SIG _{E2 of} the first receiver E1 and the second Receiver E2 be ensured in a reliable manner that it is in the received by the respective receivers E1, E2 receive signals SIG _E1 , SIG _E2 actually at the intended location of the track section G received or read, unadulterated receive signal SIG _E1 or SIG _E2 acts.

FIG. 4 shows a schematic representation to illustrate an embodiment of the method according to the invention a graph with a transmit signal and two receive signals. Shown here is the amplitude A as a function of time t for a transmit signal SIG _S , a first receive signal SIG _E1 and a second receive signal SIG _E2 . According to the presentation of the FIG. 4 The illustrated signals SIG _S , SIG _E1 , SIG _E2 differ not only in terms of their amplitude A, but in particular also in terms of their phase.

Based on the illustrated signals SIG _S , SIG _E1 , SIG _E2 , therefore, the phase shift PH _{S, E1} between the transmit signal SIG _S and the first receive signal SIG _E1 , the phase shift PH _{S, E2} between the transmit signal SIG _S and the second receive signal SIG _E2 and / or the phase shift PH _{E1, E2} between the first receive signal SIG _E1 and the second receive signal SIG _{E2 are} determined. An evaluation of the phase shifts PH _{S, E1} , PH _{S, E2} , PH _{E1, E2} , for example by comparison with a respective corresponding reference phase shift, allows a review of the signal path of the respective receive signals SIG _E1 or SIG _E2 or both receive signals SIG _E1 , SIG _E2 . In accordance with the above explanations, it is possible in this case in particular to detect faults with respect to the cables or lines between the track and the respective receiver, whereby advantageously, in particular, a falsified one Free message, ie the erroneous display of a free state of the track section, is avoided.

Claims (12)

1. Apparatus (V) for detection of the occupied or free state of a track section (G) having

   - a transmitter (S) for feeding a transmitted signal (SIG_S) in the form of an AC voltage into the rails (F) of the track section (G),

   - a first receiver (E1) for receiving a first received signal (SIG_E1) which is produced by transmission of the transmitted signal (SIG_S) via the rails (F) of a first part of the track section (G), and

   - a second receiver (E2) for receiving a second received signal (SIG_E2) which is produced by transmission of the transmitted signal (SIG_S) via the rails (F) of a second part of the track section (G),

   - wherein the apparatus (V) is designed to determine the phase shift (PH_E1,E2) between the first received signal (SIG_E1) and the second received signal (SIG_E2).
2. Apparatus according to Claim 1,
   characterized in that
   the apparatus (V) is designed to compare the phase shift (PH_S,E1, PH_E1,E2) with at least one reference phase shift.
3. Apparatus according to Claim 2,
   characterized in that
   the apparatus (V) is designed to produce a fault signal, which indicates a disturbance state, on the basis of the comparison between the phase shift (PH_S,E1, PH_E1,E2) and the reference phase shift.
4. Apparatus according to Claim 3,
   characterized in that
   the apparatus (V) is designed to output the fault signal in the form of a visual and/or audible warning message.
5. Apparatus according to one of the preceding claims,
   characterized in that

   - the transmitter (S) is designed to feed a transmitted signal (SIG_S), which has been coded by means of modulation, into the rails (F) of the track section (G), and

   - the apparatus (V) is designed to compare the modulation on at least one of the received signals (SIG_E1, SIG_E2) with the modulation on the transmitted signal (SIG_S).
6. Apparatus according to one of the preceding claims,
   characterized in that
   the apparatus (V) is designed to transmit data signals via the rails (F) of the track section (G) to a rail vehicle which is occupying the track section (G).
7. Method for operation of an apparatus (V) for detection of the occupied or free state of a track section (G),
   wherein

   - a transmitted signal (SIG_S) in the form of an AC voltage is fed into the rails (F) of the track section (G),

   - a first received signal (SIG_E1) which is produced by transmission of the transmitted signal (SIG_S) via the rails (F) of a first part of the track section (G) is received, and

   - a second received signal (SIG_E2) which is produced by transmission of the transmitted signal (SIG_S) via the rails (F) of a second part of the track section (G) is received,

   characterized in that
   the phase shift (PH_E1,E2) between the first received signal (SIG_E1) and the second received signal (SIG_E2) is determined.
8. Method according to Claim 7,
   characterized in that
   the phase shift (PH_S,E1, PH_E1,E2) is compared with at least one reference phase shift.
9. Method according to Claim 8,
   characterized in that
   a fault signal, which indicates a disturbance state, is produced on the basis of the comparison between the phase shift (PH_S,E1, PH_E1,E2) and the reference phase shift.
10. Method according to Claim 9,
    characterized in that
    the fault signal is output in the form of a visual and/or audible warning message.
11. Method according to one of Claims 7 to 10,
    characterized in that

    - a transmitted signal (SIG_S), which has been coded by means of modulation, is fed into the rails (F) of the track section (G), and

    - the modulation on at least one of the received signals (SIG_E1, SIG_E2) is compared with the modulation on the transmitted signal (SIG_S).
12. Method according to one of Claims 7 to 11,
    characterized in that
    data signals are transmitted via the rails (F) of the track section (G) to a rail vehicle which is occupying the track section (G).

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