Method for carrying out an extended braking test in a vehicle combination of track-guided vehicles

Abstract

The invention relates to a method for carrying out a braking test in a vehicle combination of track-guided vehicles, wherein a measured value describing the braking state is generated in each vehicle by means of a sensor and said measured value is compared to at least one specified reference value in a computer-assisted manner. According to the invention, the time required to apply the brakes in each vehicle of the vehicle combination is measured, in that the time difference between a point in time of an application request to apply the brakes and a point in time when an application-related reference value is reached is determined and an error signal is generated if the time required to apply the brakes exceeds a specified application-related maximum value, and / or the time required to release the brakes in each vehicle of the vehicle combination is measured in that the time difference between a point in time of a release request to release the brakes and a point in time of reaching a release-related reference value is determined and an error signal is generated if the time required to release the brakes exceeds a specified release-related maximum value. The invention also relates to a vehicle suitable for carrying out the described method and to a computer program. Advantageously, a degradation of the brake system of the vehicle combination can be determined during operation by means of the method according to the invention, and a maintenance requirement can be flexibly displayed in the event that operational risks arise.

Description

[0001] Method for carrying out an extended brake test in a convoy of track-guided vehicles

[0002] Technical area

[0003] The invention encompasses a method for conducting a brake test in a convoy of track-guided vehicles. The invention further encompasses a vehicle that can be coupled with other vehicles to form a track-guided vehicle convoy. The invention further encompasses a computer program product containing program instructions. The invention further encompasses a computer-readable storage medium containing data.

[0004] Technical background

[0005] Freight car brakes are typically controlled by a brake control valve, which converts the braking request into a suitable brake pressure via the freight train's main air line. This pressure is then converted into a mechanical movement via a brake cylinder, which is transmitted to the brake pads via a more or less complex linkage to press (apply) or lift (release) the brake pads against the wheel rims (or, depending on the design, the brake discs).

[0006] To ensure the braking capability of a wagon, several manual tests are required for safety reasons. In Europe, for example, a so-called brake test is carried out after a new train has been assembled before the first journey. During this brake test, it is manually checked whether the brakes can be applied and released on the command of the person authorized to carry out the brake test. Furthermore, a detailed inspection of the brakes is carried out after set activities or deadlines during the train's journey. The Maintenance Guideline for Brakes and Compressed Air Reservoirs on the NE Railways - IBD-NE, for example, currently provides for the following four types of

[0007] 5 brake revisions before:

[0008] When the brake degrades, the response and release behavior of the brake changes due to wear or dirt deposits.

[0009] 10 The presence of degradation can currently only be determined in BR1 to BR3. While the basic functionality of the brakes can be checked relatively easily during the brake test, in order to determine brake degradation, the vehicle must be taken to a workshop for the necessary brake overhauls BR1

[0010] 15 to BR3. This involves testing the brake cylinder's behavior over time by applying test pressures to the main air line and the T-pressure line and measuring the pressure curve in the brake cylinder. However, brake degradation that occurs within specified testing intervals is often the cause of expensive consequential damage.

[0011] 20 during operation (e.g., flat spots on wheels due to slow release). However, responding to this by shortening the intervals would be uneconomical. For the automation of the brake test, DE 10 2021 203 122 A1 and the unpublished European patent application with the file number 24151621.0 describe systems that can determine the braking condition (usually with the brake applied and released) of each vehicle in the convoy before a newly formed train sets off for the first time during the prescribed brake test and transmit it to a central device. Sensors on the vehicle determine the actual braking condition and transmit it to the device with a technically determined latency.

[0012] The state of the art described above presents the problem that progressive wear-related deterioration of a vehicle's brakes cannot be detected during progressive operation. This degradation is acceptable up to a certain degree as long as it does not impact the basic function of the brake in a safety-relevant manner. The basic function of the brake is that it can be applied and ensures that the vehicle is braked in this state, and that it can also be released again. Furthermore, the probability of brake failure must be sufficiently low within the framework of the defined safety requirements. To meet the required safety in this regard, the brake tests described above are carried out, although these involve downtime for the vehicles in question.

[0013] Summary of the invention

[0014] The object of the invention is to resolve the described problems in the prior art. In particular, it is to provide a method for conducting a brake test in a convoy of rail-guided vehicles, a vehicle for conducting such a method, a computer program product containing program instructions, and a computer-readable storage medium, with which required maintenance measures for the brakes, which are associated with downtimes of the vehicles in question, can be avoided.According to a first aspect of the invention, a method is described for carrying out a brake test in a vehicle convoy of track-guided vehicles (the vehicle convoy typically consists of a plurality of wagons, in particular freight wagons, pulled by at least one locomotive, wherein both the locomotive and the wagons represent vehicles within the meaning of this description of the invention), in which in each vehicle a measured value describing the braking state (for example the position of the brake) is generated using at least one sensor and this measured value is compared with at least one predetermined reference value in a computer-assisted manner.

[0015] Measured values ​​that describe a braking condition and can be determined using a sensor in the vehicle in question can have different properties. For example, setting angles in a braking mechanism can be determined. Another option is to measure linear movements in the braking mechanism. This assumes that the kinematics of the braking mechanism with regard to applying and releasing the brakes is known, so that certain braking conditions can be deduced from the measured values. In particular, a completely released state of the brake as well as an applied state of the brake can be determined. For this purpose, the measured value generated in each case is compared with at least one predetermined reference value. In other words, this reference value describes exactly the measured value to be expected for the brake condition to be verified.Preferably, a release-related reference value is used for the released state of the brake and / or an application-related reference value is used for the applied state of the brake.

[0016] Optionally, a tolerance range can be specified for the reference value to be checked. In this case, a check would be carried out to determine whether the measured value in question lies within the tolerance range specified for the reference value. If the check is positive, a test result would be generated stating that the measured value has reached the reference value. However, this is not absolutely necessary. In particular, when the aim is to reach the reference value, the measured value usually approaches the reference value from one side (for example, approaching the application-related reference value when the brake is applied and approaching the release-related reference value when the brake is released). Failure to reach the relevant reference value would therefore indicate an existing error.

[0017] To avoid any misunderstanding, it should be noted at this point that individual claim features are numbered consecutively with lowercase Latin letters, regardless of the claim numbering. This means that each letter appears only once in the entire set of claims, allowing the relevant claim features to be clearly addressed without mentioning the claim number. Therefore, the order of the letters is irrelevant.

[0018] According to the invention, it is provided that a) the time required to apply the brakes is measured in each vehicle of the vehicle convoy by determining the time difference between a time of an application request (the application request can, for example, consist of a brake command in signal terms or mechanically of a pressure reduction in the brake control line (HL)) for applying the brakes and a time at which an application-related reference value is reached (for example, the position of the brake with the brake pads applied), b) an error signal is generated if the time required to apply the brakes exceeds a predetermined application-related maximum value, and / or that c) the time required until the brakes are released is measured in each vehicle of the vehicle convoy,by determining the time difference between a time of a release request (the release request can, for example, consist of a release command in signal terms or also mechanically of a pressure increase in the brake control line (HL)) for releasing the brakes and a time at which a release-related reference value is reached (for example, the position of the brake with the brake pads released or at least not in contact, in particular in a design-specified release position of the brake), d) an error signal is generated if the time required to release the brakes exceeds a predetermined release-related maximum value.

[0019] In order to be able to determine the time required in the manner described above, the measured value can be generated repeatedly or continuously in one design. This ensures that the point in time at which the measured value reaches the release-related or application-related reference value can be determined. With repeatedly generated measured values, the accuracy in determining the time required depends on the cycle time when repeating the individual measuring steps to generate the measured value. According to another design, a pressure switch can also be used which switches on or off depending on the applied pressure. The switching should preferably be triggered mechanically. It always occurs when a predetermined switching pressure is exceeded or undershot.

[0020] The time required to apply and release the brake allows for inferences about the brake condition. The relationship exists that both applying and releasing the brakes takes longer with the progressive degradation of the braking system of the vehicles in the convoy, as wear in the braking system typically leads to increased resistance and / or friction losses in the brake mechanism upon application. This makes it possible to specify a maximum value that should not be exceeded by the time required to apply and / or release the brakes, as exceeding this value would result in a degradation of the braking system, which the operator would no longer accept.It must be taken into account that progressive degradation increases the risk of comparatively expensive consequential damage to the braking system and also increases the operating times of the vehicle convoy, making operation less economical. The maximum values ​​for applying and releasing the brakes can be determined for each individual vehicle using a calibration procedure. This requires at least one sensor in the main air line (hereinafter also referred to as HL), preferably in the main air line of each vehicle in the convoy, if the application or release request is to be related to a pressure drop or pressure increase in the main air line.As an alternative to such a sensor in the main brake line, serious degradation can also be detected by comparing the time delay of a car when applying or releasing the brake in the central unit of such a system with the behavior of other cars. If the delay times of a car exceed the empirically determined maximum values ​​​​in the following table, action is definitely necessary. Since a central processor controlling the process (e.g. in the locomotive) does not know an absolute time for the application of the brake, the first car in the trainset that reported a signaling or release status can also be used for comparison, and the minimum possible value according to the table can be deducted from its signal.

[0021] The terms used in this description of the invention have the following meaning.

[0022] When referring to a sensor, the statement applies to any type of sensor used in the system according to the invention, i.e., to geometry sensors as well as pressure sensors. When referring to pressure sensors, the statement applies to all pressure sensors in the system. Otherwise, a distinction is made between a first pressure sensor, a second pressure sensor, and a third pressure sensor, whereby a first pressure sensor, a second pressure sensor, and a third pressure sensor can be used in every vehicle (more on this below).

[0023] A distinction is made between an application-related reference value and a release-related reference value. As already explained, the reference values ​​are used to determine when a specific brake position has been reached. They are available for comparison with the measured values ​​generated according to the method. The application-related reference value, as its name suggests, describes a value for the measured value that is reached when the brake is applied. Accordingly, the release-related reference value, as its name suggests, describes a value for the measured value that is reached when the brake is released, preferably when the brake is completely released. If, in the context of this description of the invention, reference is generally only made to reference values, the statements made then refer to both the application-related and the release-related reference value.

[0024] A distinction is made between an application-related maximum value and a release-related maximum value. As already explained, the maximum values ​​are used to determine whether a certain degree of brake degradation has been reached. They are available for comparison with the time requirements (application and release) calculated according to the method. If, in the context of this description of the invention, only maximum values ​​are generally referred to, the statements made refer to both the application-related and the release-related maximum values.

[0025] A device is computer-aided or computer-implemented if it has at least one computer or processor, or a method if at least one computer or processor carries out at least one method step of the method.

[0026] A computing environment is an IT infrastructure consisting of functional components such as processors, memory units, programs, and data to be processed by the programs, which are used to execute at least one application that has to perform a task. Additional functional components can consist of sensors and actuators that enable the computing environment to interact with the outside world. The IT infrastructure can also be organized as a network of these functional components.

[0027] A cloud (also known as a computer cloud or data cloud) is a computing environment for cloud computing. This refers to an IT infrastructure made available via interfaces of a network such as the internet. It typically includes storage space, computing power, or software as a service, without the need to install these on a computing instance using the cloud. The services offered within the framework of cloud computing span the entire spectrum of information technology and include, among other things, IT infrastructure, platforms, software, and computing power. The cloud provider distributes the offered resources to cloud users according to their needs, with the goal of optimally utilizing the resources.

[0028] Since high security standards apply in railway technology with regard to functionality (operational reliability, safety) and vulnerability (transmission reliability, security) of computer-implemented solutions, the functionalities of a cloud used in railway technology are typically limited in terms of their shared availability. Restrictions are therefore necessary, particularly with regard to access by a potentially unlimited group of cloud users. However, access must also be limited with regard to the sharing of computing resources between different computing instances, with a view to the required redundancy. A technology that takes these restrictions into account for railway technology is also referred to as a private cloud in the context of this invention, even if a private cloud only partially fulfills the technical features associated with cloud technology.

[0029] Computers are electronic devices with data processing capabilities consisting of multiple functional components. Computers can be, for example, clients, servers, handheld computers, communication devices, and other electronic devices for data processing that may have processors and memory units and can also be connected to a network via interfaces.

[0030] Processors can be, for example, converters, sensors for generating measurement signals, or electronic circuits. A processor can be a central processing unit (CPU), a microprocessor, a microcontroller, or a digital signal processor, possibly combined with a memory unit for storing program instructions and data. A processor can also be a virtualized processor or a soft CPU.

[0031] Storage devices can be implemented as computer-readable memory in the form of a random-access memory (RAM) or data storage (hard disk or data carrier).

[0032] Program modules are individual software functional units that enable a program sequence of method steps according to the invention. These software functional units can be implemented in a single computer program or in several communicating computer programs. The interfaces implemented in this way can be implemented in software within a single processor or in hardware if multiple processors are used.

[0033] Interfaces can be implemented in hardware, for example wired or as a radio connection, or in software, for example as interaction between individual program modules of one or more computer programs.

[0034] The advantage of the invention is that maintenance intervals requiring the affected vehicles to be taken out of service can be selected flexibly, depending on the actual need. Maintenance intervals can be both shorter and longer than those standardized according to the state of the art. If degradation can be detected during operation, the consequential costs associated with degradation can be reduced accordingly by avoiding consequential damage. The economic damage resulting from a needs-based shortening of the relevant maintenance interval is significantly lower in comparison. Conversely, it can be detected that no relevant degradation has yet occurred after the scheduled brake maintenance period has expired, and the corresponding period can be extended, thus avoiding the need to take the vehicles out of service and the associated costs.This in turn reduces maintenance costs for the vehicles in question.

[0035] The solution presented enables the automatic detection of a defect in the braking system during brake tests, which must be carried out anyway during operation of the vehicle convoy, without the vehicle having to be taken out of service for a separate brake test. The difference according to the invention, however, is that the brake tests carried out during operation have so far only been used for a basic brake test. This has so far only related to whether the brakes can be applied and released correctly. However, these two basic functions are generally still fulfilled even with progressive degradation of the braking system, so that no conclusions could be made regarding the degradation itself. For this purpose, the invention additionally examines a time component.

[0036] According to a further aspect of the invention, a vehicle is described that can be coupled with other vehicles to form a track-guided vehicle convoy. The vehicle is equipped with e) a sensor that can generate a measured value describing the braking state, f) a computing environment. According to this aspect, the invention provides that the computing environment is also configured to perform the two steps a) and b) and / or the two steps c) and d) according to claim 1.

[0037] The computing environment comprises at least one processor in each vehicle. Preferably, this processor is signal-connected to a memory unit in the vehicle. Preferably, the computing environment further enables an interface (wireless or wired) between said processor and other processors, for example, a central processor (which performs or supports the function of a central processing unit) in a locomotive. The advantages associated with this aspect of the invention have already been explained above, and reference is made to these advantages.

[0038] According to a further aspect of the invention, a computer program product is described, containing program instructions that can be executed by a computer. According to this aspect, the invention provides that the method is carried out computer-assisted according to one of the claims relating to the method.

[0039] According to the invention, a computer program product containing program modules is described with program instructions, wherein the program modules can run on the same or multiple processors. The method according to the invention and / or its exemplary embodiments can be implemented by means of the computer program product, which can comprise one or more computer programs, and the above-described advantages are achieved by the implementation.

[0040] According to a further aspect of the invention, a computer-readable storage medium is described, containing data stored as data records on the storage medium. According to this aspect, the invention provides that the data records make the above-described computer program product executable according to the last preceding claim. Furthermore, a provision device for storing and / or providing the computer program in the form of a computer-readable storage medium is described. The provision device is, for example, a storage unit that stores the computer program and makes it available for retrieval.Alternatively or additionally, the provision device is a network service, a computer system, a server system, in particular a distributed, for example cloud-based computer system or virtual computer system, which stores the computer program on a computer-readable storage medium and preferably provides it in the form of a data stream.

[0041] The provision takes place in the form of program data sets describing program modules as a file, in particular as a download file, or as a data stream, in particular as a download data stream, of the computer program. The computer program is transferred, for example, using the provision device into a computing environment, so that the method according to the invention can be executed in one or more computing instances of this computing environment.

[0042] Embodiments of the invention

[0043] Variants describing further developments of the invention are explained below without limiting the basic idea of ​​the invention.

[0044] According to a variant, the aspects of the invention explained above are determined by a pressure sensor measuring the pressure prevailing in a pneumatic actuator system.

[0045] Pneumatic actuator systems are widely used to actuate the brakes of rail-guided vehicles, preferably as indirect pneumatic brakes. All vehicles in a train are connected to a main air line so that the brakes can be triggered centrally, preferably in the locomotive, by reducing the pressure in the main air line. To release the brakes, the pressure in the main air line is increased again. The main air line also serves to fill local pressure accumulators in the vehicles. In the event of a braking request, these pressure accumulators are used to apply the brake pads to the friction partners (preferably the wheels) by means of the pneumatic brake cylinders by building up excess pressure in the brake cylinders. In this case, the main air line acts as a pneumatic signal line, accessing control valves to control the brake cylinders.

[0046] An advantage of this variant is that a pressure measurement provides a particularly simple and reliable sensor method for generating the information required for the application request and the release request in the form of a measured value for controlling the method according to the invention.

[0047] According to a variant, the aspects of the invention explained above are determined in that the one pressure sensor as the first pressure sensor measures the pressure prevailing in a main air line.

[0048] An advantage of this variant is that the pressure in the main air line can be determined as a representative of the entire braking system of the vehicle using at least one pressure sensor. If this pressure increases sharply, this can be interpreted as a release request. If the pressure then drops sharply again, this can be interpreted as an application request. Sharp is defined as pressure fluctuations in the main air line that are outside of operational requirements and occur without a release request or application request during fault-free operation of the vehicle. An upper limit value for the pressure increase and a lower limit value for the pressure drop can be defined here, so that the time of a braking request is determined as soon as the pressure in the main air line falls below the lower limit value and a release request is determined when the pressure rises above an upper limit value.

[0049] According to a variant, the aspects of the invention explained above are determined by the fact that in each vehicle a first pressure sensor measures the pressure prevailing in the main air line.

[0050] The method of measuring the pressure in the main air line in each of the vehicles is, in terms of its operating principle, the same as that described above, where only one pressure sensor, the first in the locomotive, is used in the main air line. However, in each vehicle the pressure measured in that vehicle is measured by a first pressure sensor in order to determine the time of the braking request. This takes into account the fact that the pressure curve in the main air line does not run parallel in time in all vehicles due to the length of the vehicle convoy. The further the vehicle in question is from the compressed air source for feeding an increase in pressure into the main air line, the greater the time delay until the desired pressure change occurs in the vehicle in question when the pressure at the compressed air source changes.

[0051] One advantage of this variant is that, when using a first pressure sensor in each vehicle, a vehicle-specific time period can be determined from the application or release request to the actual application or release of the brake. This makes it possible to detect and localize errors occurring individually in the vehicles. In addition, the additional sensors can also be used to determine an additional time period for evaluating the braking function. This time period begins with a change in the pressure at the compressed air source and ends with a similar change in the pressure in the vehicle in question. This time period can also be referred to as a response delay that is individual for each vehicle. This time period can, for example, provide information about the vehicle's position in the convoy.

[0052] According to a variant, the aspects of the invention explained above are determined by the fact that in each vehicle a second pressure sensor measures the pressure prevailing in a brake cylinder for actuating the brake.

[0053] Brake cylinders are typically used as actuators to convert the pressure in the main air line into a mechanical actuating movement. These are fed from local pressure vessels in the vehicle, at least in indirect pneumatic brakes. These allow pressure to build up in the brake cylinder via control valves when the pressure in the main air line drops.

[0054] An advantage of this variant is that additional measured values ​​can be generated for each vehicle, providing additional information about the function of the pneumatic brake used in the vehicle. For example, malfunctions of the brake control valve for the brake cylinders can be detected. This allows for rapid response to the detection of errors and, as a consequence, at least the generation of an error signal in the manner already described.

[0055] According to a variant, the aspects of the invention explained above are determined in that in each vehicle a third pressure sensor measures the pressure prevailing in an actuator in the form of a pneumatic cylinder designed as a second brake cylinder for actuating the brake.

[0056] The function and the associated advantages of the variant explained above have already been explained. Providing a third pressure sensor is advantageous if a second brake cylinder is also used, so that the measuring method can advantageously differentiate between the first brake cylinder and the second brake cylinder, as two measurement results are available. In trouble-free operation, the pressure conditions in both brake cylinders should be approximately symmetrical, i.e. the same. If there are major asymmetries (above a specified limit value) in the measurement results, this indicates a malfunction. A tolerance range can be specified for the deviation between the two measurement results generated by the second pressure sensor and the third pressure sensor. An error is output if the specified tolerance range for a deviation in the measurement results is exceeded.

[0057] According to one variant, the above-explained aspects of the invention are determined by the sensor being a geometry sensor that measures a geometric state variable in the brake mechanism. The term "geometry sensor" is to be understood with regard to the sensor's function, namely that it can measure a geometric state variable of the brake mechanism. A force sensor for measuring a force acting in the brake linkage can also be used.

[0058] Geometric state variables of the brake mechanism describe the geometric relationships that inevitably change when the brakes are applied and released. Typically, mechanical levers of a mechanical coupling mechanism are rotated or shifted relative to each other, whereby the actuating movement of an actuator, usually a brake cylinder, is transmitted to the brake pads, causing them to be applied to or released from their friction partner (e.g., a brake disc, but preferably the vehicle wheel). The change in the geometry of the brake mechanism can be monitored, in particular, by monitoring the actuating angle of mechanical elements (absolute or relative to each other) or by monitoring the distance between mechanical elements or to immovable parts of the vehicle.

[0059] An advantage of this variant is that the brake mechanism has a clear geometric relationship to the brake pads due to a mechanical coupling. Therefore, the sensor's measurement result can be used directly to determine whether the brake is engaged or disengaged. Therefore, even while driving, at least one significant malfunction of the brake mechanism can be detected promptly after it occurs (with the next brake test). Furthermore, the geometry sensor can be used advantageously to determine the time at which the brake pads are engaged or disengaged for the method according to the invention.

[0060] According to one variant, the above-explained aspects of the invention are determined by using an apply command for the brake as the time of the application request and / or a release command for the brake as the time of the release request. These commands can be generated, for example, by a central control system in the locomotive and replace the previously described (central) first pressure sensor.

[0061] One advantage of this variant is that it provides a comparatively simple and therefore reliable method for determining the time of the application request or release request. For example, a corresponding application command or release command, which is generated in a central unit, can be evaluated. The application command or release command can be an electrical signal or a pneumatic signal, the latter being fed into the main air line. The electrical signal causes the pneumatic signal to be generated and is therefore deterministically linked to it. For example, a time delay from the generation of the electrical signal to the generation of the pneumatic signal can be determined and used as the basis for the method according to the invention.

[0062] Exemplary embodiments of the drawing

[0063] Further details of the invention are described below with reference to the drawings. Identical or corresponding drawing elements are provided with the same reference numerals in the individual figures and are explained repeatedly only to the extent that differences arise between the individual figures.

[0064] The exemplary embodiments explained below are preferred embodiments of the invention. In the exemplary embodiments, the described components of the embodiments each represent individual, independently considered variants of the invention, which also further develop the invention independently of one another and are thus also considered components of the invention, either individually or in a combination other than that shown. Furthermore, the described components can also be combined with the variants of the invention described above.

[0065] Figure 1 shows a schematic illustration of an embodiment of the device according to the invention, designed as a track-guided vehicle, with its interactions between the functional components used.

[0066] Figure 2 shows an alternative embodiment of the device according to the invention (bogie as part of the track-guided vehicle with braking device) with its interactions between the functional components used schematically in three-dimensional representation.

[0067] Figure 3 shows an embodiment of a computing environment for the device according to Figure 1 as a block diagram of the individual functional components and the interfaces formed between them, wherein individual computing instances execute program modules which can each run in one or more of the computers shown as examples and wherein the interfaces shown can accordingly be implemented in software in one computer or in hardware between different computers.

[0068] Figure 4 schematically shows a vehicle combination consisting of several embodiments of the track-guided vehicle according to the invention, wherein a locomotive is arranged at the front of the vehicle combination and wherein the vehicle combination is set up to carry out an embodiment of the method according to the invention.

[0069] Figure 5, consisting of the sub-figures 5A and 5B, shows an embodiment of the method according to the invention as a flow chart, wherein the method steps shown can be implemented individually or in groups by program modules and wherein the computing instances and interfaces according to Figure 3 are indicated by way of example.

[0070] Figure 6 schematically shows various courses of measurement results, with the measurement results of the geometry sensor as well as the first and second pressure sensors being shown over time t, and with correct courses of the measurement result being shown by a solid line and measurement results that indicate an error being shown by dashed lines.

[0071] Detailed description of the implementation examples

[0072] Figure 1 shows a vehicle FZ in the form of a freight wagon. This vehicle FZ has a bogie DG at the end shown, which supports the wheels RD on two axles. Also shown schematically is a brake linkage BRG, which transmits the movement of an actuator AKT in the form of a pneumatic cylinder to the brake pads BRB, whereby the brake pads BRB act directly on wheel rims (not shown) of the wheels RD. The brake linkage BRG is shown schematically. It is a mechanical transmission (linkage consisting of coupling rods, i.e. pull rods, push rods and levers, and joints) for transmitting the actuating movement of the actuator AKT to the brake pads BRB. The transmission consists of pull and push rods ZSS, which at least mainly perform a translational movement, indicated in Figure 1 by double arrows parallel to the rod orientation.There are also levers that can be pivoted around a pivot axis, indicated by curved double arrows perpendicular to the lever's orientation. Pivot axes or joints are indicated by circles at the ends of the ZSS pull or push rods and the levers, or in their center. Furthermore, the mounting of the AC axles on the FZ vehicle, as well as the levers and pull and push rods, is indicated by fixed bearings FL, with the respective hatching indicating the rigid connection to the FZ vehicle (including the bogie).

[0073] One of the levers is the actuator STE, which is pivoted about the indicated fixed bearing FL and is moved by the pull or push rod ZSS coming from the actuator AKT. A geometry sensor GSN in the form of a measuring acceleration sensor is rigidly attached to this actuator, so that it pivots back and forth with the actuator STE. There is also a reference acceleration sensor RBS, which is rigidly connected to the vehicle FZ, according to Figure 1 to the bogie DG (which forms part of the vehicle FZ). The measuring acceleration sensor and the reference acceleration sensor RBS communicate with an output device AE via radio interfaces (not shown in detail). The output device AE also contains the processor for evaluating the received measured values.The reference acceleration sensor RBS is used to incorporate the acceleration due to gravity into the measurement result generated by the measurement acceleration sensor, in a conventional manner, so that this does not influence the calculation of the angle change of the actuator STE. Alternatively, cable interfaces can also be used (not shown).

[0074] Furthermore, Figure 1 shows that a second pressure sensor DNS2 is arranged on the actuator (or, in a manner not shown, in a compressed air line leading to the actuator). This is a sensor with which the pressure prevailing in the pneumatic cylinder can be determined. This makes it possible to additionally evaluate the degradation of the braking system shown in Figure 1 with regard to the temporal pressure curve in the pneumatic cylinder. In Figure 2, a vehicle FZ is indicated by a schematically shown bogie DG, which supports the wheels RD in two axles of a twin axle. Also schematically shown is a braking device BV arranged in a space ZR between the axles, which transmits a movement of an actuator AKT to the brake pads BRB, whereby the brake pads BRB act with a normal force Fn on wheel rims (not shown) of the wheels RD, creating a braking force Fb.

[0075] The braking device BV is depicted three-dimensionally with a first sub-unit TE1 and a second sub-unit TE2. The first sub-unit TE1 has a housing GHS, which houses a mechanism (not shown in detail) for transmitting the actuating movement of the actuator AKT, which is also housed in the housing GHS, and the first pressure sensor (not shown) (the second pressure sensor can be housed in a second, similar braking device (not shown) on another bogie of the car). The mechanism (e.g., a coupling gear) transmits an actuating movement to push rods ZSS in a manner (also not shown), which at least primarily perform a translational movement in order to increase or decrease a distance between the two sub-units (TE1 ... TE2).

[0076] The braking device BV is suspended in the bogie DG using four bearing rods LST. The bearing rods LST in turn have ball heads KKP, which are fastened in the bogie DG in a conventional manner (not shown). The ball heads KKP allow movement primarily in a horizontal direction, namely in a direction of travel FR or against this direction of travel FR. The invisible suspensions of the bearing rods LST in the braking device BV describe circular arcs around the fixed points in the bogie DG defined by the ball heads KKP. However, since the bearing rods LST are essentially aligned vertically, the technically relevant circular section of these circular arcs essentially results in a horizontal movement. The ball heads KKP also allow a certain amount of movement in a horizontal direction perpendicular to the direction of travel FR. However, this is structurally limited by the cheeks WG of the brake heads BKP, which carry the brake pads BRB.

[0077] Using a geometry sensor GSN, the distance between the two sub-units T1 , T1 can be determined. This distance allows a direct conclusion to be drawn as to whether the brake pads BRB are in contact with the wheels RD (brake applied state) or are released from the wheels RD (brake released state). Alternatively, a force sensor could be installed in a manner not shown such that it measures a different amount of force when the brake is applied than when the brake is released. This can be achieved by the force sensor measuring an increase in force that occurs when the brake is applied because the brake pads on the braking partner generate a driving force that is propagated in the brake mechanism.

[0078] Figure 3 shows a schematic block diagram of the interaction of the functional elements involved in the method according to the invention. A block symbolising the vehicle FZ can be seen, which comprises the geometry sensor GSN, the first pressure sensor DSN1, the second pressure sensor DSN2 and the third pressure sensor DSN3. All possible sensor types are shown here as examples, so that all method variants explained within the scope of this description of the invention can be implemented. A block symbolising a computing environment RU can also be seen, which comprises an output device AE as computing instances and is connected to a processor PR via a second interface S2. The braking device BV is shown as an example in the vehicle FZ.

[0079] The brake heads BKP of the braking device BV are actuated by a first brake cylinder BZL1. Of a further braking device, which is not shown in its entirety in Figure 3, only a second brake cylinder BZ L2 can be seen, which actuates this additional braking device. Figure 3 also shows a system consisting of the main air line HL and a first line L1 branching off from this, which supplies a brake control valve BSV with compressed air and from which a third line L3 leads to the second brake cylinder and a fourth line L4 leads to the first brake cylinder. In addition, a reservoir RV for compressed air is also connected to the brake control valve BSV via a second line L2. The braking system functions in a manner known per se.If the pressure in the main air line HL is reduced in response to the application request, the brake control valve BSV is activated in such a way that the pressure in the third line L3 and fourth line L4, fed from the reservoir RV, increases and the first brake cylinder BZL1 and the second brake cylinder BZL2 are actuated. This moves the brake heads BKP towards the braking partner (not shown) and the braking process begins. If the pressure in the main air line HL is increased again in response to the release request, the brake control valve BSV has the opposite effect, i.e. the pressure in the third line L3 and fourth line L4 is reduced and the brake heads are lifted off the braking partner again, which is why the braking process ends. The pressure curves that can be measured by the various sensors during the processes described are shown schematically in Figure 6.

[0080] All sensors are connected via a first interface S1, shown as an example, to the processor PR, which evaluates the measurement results. The processor PR is also connected via a third interface S3 to a memory device SE, wherein, for example, required reference values ​​are stored in the memory device SE. The processor PR is connected to the output device AE via the output interface S2. The output device AE is preferably a display that can present information regarding the operation of the brake, or a system with, for example, a radio interface that can transmit the information directly to a central processor ZPR, e.g., in the locomotive (see the antennas according to Figure 4).In the simplest case, the output device AE can be implemented as (at least) one light which, without any further information, simply indicates the need for maintenance (flashing when the brake pads BRB are worn beyond the wear limit, loss of brake blocks / brake pads) and the current status of the brake (lit up corresponds to applied / not lit up corresponds to released). Figure 4 shows a GL track on which a vehicle convoy FZV, consisting of three FZ vehicles and one LC locomotive, is parked. The LC locomotive and the FZ vehicles are coupled to one another via digital automatic couplers DAC (which are to be introduced as part of European harmonization for freight trains), with a section of the digital automatic coupler DAC shown enlarged. The enlargement makes it clear that this contains a main air line HL and a line that forms a BUS bus system.The main air line HL runs through the entire vehicle convoy FZV as well as the bus system BUS, so that the locomotive LC can supply the entire vehicle convoy FZV with compressed air and also form an information network with it.

[0081] Figure 4 also shows an alternative way of establishing communication between the FZ vehicles and the LC locomotive, namely via a Cloud CLD. For this communication, AT antennas are located on both the LC locomotive and the FZ vehicles, which are connected to the Cloud CLD via interfaces S4, S5, S6, and S7. The illustrated solution with a Cloud CLD offers an alternative if communication between the FZ vehicles and the SC locomotive via a digital automatic coupling (DAC) is not possible.

[0082] Overall, a computing environment RU is created by the communicatively interconnected processors PR in the vehicles FZ and the computer CP in the locomotive LC. The computer CP has a central processor ZPR, which is connected to a central storage device ZSE via an eighth interface S8. In the individual vehicles FZ, a processor PR and a storage unit SE are provided, as already explained, which are each connected to each other via a third interface S3. This configuration can be found in each of the vehicles FZ. In this respect, these vehicles FZ are technically constructed in the same way as shown in Figure 3. A single first pressure sensor DSN1 is arranged in the main air line HL, which can be seen in the enlarged detail of the digital automatic coupling DAC. This pressure sensor can be used to measure the pressure prevailing in the main air line HL.Figure 4 indicates that the first pressure sensor DSN1 is a centrally located sensor in the locomotive that measures the pressure in the main air line HL for the entire vehicle convoy ZV. Not shown, but equally conceivable, is the solution already described, in which a first pressure sensor DSN1 is installed in each of the vehicles FZ. This creates redundancy for the measurement. Furthermore, pressure differences in the individual vehicles can then be determined, which could indicate degradation of the braking system and make a time delay in the pressure build-up within the vehicle convoy FZV measurable.

[0083] In the following, the method according to the invention will be explained step by step, as shown in the flowchart in Figure 5. Figure 5 also shows, by way of example, boxes in which functional components or computing instances according to Figures 1 to 4 the individual steps can be performed. To the extent that the interfaces according to Figures 1 to 4 are used, these are also indicated in Figure 5.

[0084] Figure 5 shows an example of the process flow for the measuring method according to the invention. It should be noted that the method is carried out in each vehicle of the vehicle convoy, specifically with the first pressure sensor DSN1 and the second pressure sensor DSN2 (however, the process would be analogous if other sensors were used, for example the geometry sensor or a force sensor). After the method has been started, the available parameters are loaded from the storage device SE. In a query step RW?, a check is carried out to determine whether the required reference values ​​are already available. If not, for example, there is an unknown combination of vehicle type and brake type for which reference values ​​are not yet available, which is why a calibration step CALIB is carried out.A calibration step may also be necessary if, for example, the brake pads continue to wear down and the reference values ​​therefore need to be adjusted.

[0085] During calibration, the brakes are first released in a deactivation step UNLOCK. Then, in a measuring step MSRE, an initial measurement result ME1 is generated by the first pressure sensor DSN1 (alternatively, a measured value from the geometry sensor could also be used here, not shown). In a subsequent calculation step CALC, a missing release-related reference value RWL is calculated from this. Taking into account a release request determined by the first pressure sensor in the measuring step MSRE (due to a pressure change in the main air line), the time required to release the brake can also be calculated in the calculation step CALC. The next step is a LOCK activation step for the brake so that the brake pads contact the brake stop (e.g., the wheels RD).The measurement and calculation steps MSRE and CALC described above are repeated and provide the application-related reference value RWA and the time required to apply the brake for the second measurement result ME2 of the second pressure sensor DSN2.

[0086] In the embodiment shown in Figure 5, the calculation of the reference values ​​(if not yet available) is performed by the processor PR in the relevant vehicle, which also provides computing capacity for the CALC calculation step, or by the computer CP in the locomotive. However, these are only exemplary embodiments; the computing environment can also be configured differently. It is also possible for the measurement results to be transferred to the cloud. This represents a configuration described in Figure 4.

[0087] The required measured values, reference values, and time requirements can be transferred to the storage device SE by the processor PR in a configuration as shown in Figure 2. In the next step, based on the time required to release the brake, a release-related maximum value LMX is derived for the time required, which corresponds at least to the associated calculated time required, and based on the time required to apply the brake, an application-related maximum value AMX is derived for the time required, which also corresponds at least to the associated calculated time required (which are also transferred to the storage device SE by the processor PR in a configuration as shown in Figure 2).

[0088] If reference values ​​and maximum values ​​already exist, the calibration step CALIB can be skipped. If the relevant reference values ​​and maximum values ​​are already contained in the storage device, they can be immediately retrieved from the storage device. This is indicated in Figure 5 by the double arrows. This is followed by a test step TEST to check the degradation state of the brake. This is the actually important step in the sense of the invention. This can be carried out both at standstill for the purpose of a "small" brake test, e.g., if the train has to stop while in motion, and during operation accompanying a braking application (application request) with subsequent release of the brakes (release request).

[0089] For this purpose, a brake activation step LOCK is performed to apply it. Subsequently, the measurement MSRE, the second measurement result ME2 by the second pressure sensor DSN2 and the first pressure sensor DSN1, and the calculation CALC of the time required T for applying the brake are performed, as already described above. The current measurement result can then be transferred (in the case of a configuration similar to Figure 2, by the processor PR to the storage device SE). The processor PR then checks whether the time required T for applying the brakes exceeds the specified application-related maximum value AMX.If an exceedance is detected, an error signal ERR is output in an output step OUTPUT. This error signal can be sent directly to the output device AE as shown in Figure 3 (for forwarding to the cloud CLD or the computer CP in the locomotive LC) or stored as an error signal ERR in the storage device SE for later output. For the other case, the process proceeds as follows.

[0090] The prescribed procedure is repeated with the brake released. For this purpose, a brake deactivation step (UNLOCK) is performed. Subsequently, the first measurement result (ME1) is measured and, if necessary, calculated (MSRE, CALC) by the sensor and the first pressure sensor (DSN1), as described above. The current measurement result can then be transferred (in the case of a configuration similar to Figure 2, by the processor PR to the storage device SE). The processor PR then checks whether the time required T for releasing the brakes exceeds the specified release-related maximum value (LMX).If an exceedance is detected, an error signal ERR is output in an output step OUTPUT. This error signal can be sent directly to the output device AE as shown in Figure 3 (for forwarding to the cloud CLD or the computer CP in the locomotive LC) or stored as an error signal ERR in the storage device SE for later output. For the other case, the process proceeds as follows.

[0091] Additionally, a query can be used to check whether a deviation of a determined temporal pressure curve DVM in the actuators, measured by the second pressure sensors DSN2, corresponds to a reference pressure curve DVR. If this is not the case, an error message can also be issued, as indicated in Figure 5. Otherwise, the test procedure is complete, and the process can be stopped.

[0092] Not shown in Figure 5 is a further test of the error signals ERR, whereby the further investigation can be carried out centrally by the computer CP or decentralized by the processors PR of the vehicles FZ in question in a manner not shown. The analysis of the quality and / or quantity of the errors then allows additional conclusions to be drawn, in particular the detection of degradation of the braking system, which requires additional maintenance measures (immediately or within a specified period of time after detection). This can provide valuable information as to whether, due to the generated error signal ERR, further operation of the vehicle in question must be stopped immediately (e.g., in the event of complete brake failure) or whether maintenance must only be carried out in the foreseeable future (e.g., in the event of advanced wear of the brake pads or degradation of the braking system).

[0093] Figure 6 shows a schematic of the signal curves of various sensors as a function of time. The signal curve of the first pressure sensor DSN1 is shown at the top. The pressure P is on the y-axis, and time T is on the x-axis. Two characteristic points of the application request AAN and the release request LAN can be seen in the signal curve. A braking period BP is also shown, which extends over the state of the (fully) applied brake. The application and release can be seen in the two graphics below, which show the signal curves of the second pressure sensor DSN2 and third pressure sensor DSN3 (pressure P over time T) in the middle and the signal curve of the geometry sensor GSM (travel s over time T; if several geometry sensors were used, they would have at least qualitatively similar signal curves) below.

[0094] The braking period BP is indicated by the first pressure sensor, the second pressure sensor, and the geometry sensor in that the sensor signal is constantly at an upper level NO. In the released state, however, the sensor signal is at a lower level NU. In the case of the apply request and release request shown in the top diagram, the sensor signal alternates between the two levels with a certain time offset, which can be recognized by the fact that the apply request and the release request are each at a certain time interval from the point at which the second and third pressure sensors or the geometry sensor experience a change in the sensor signal, represented by the vertical lines in Figure 6, which run through all three diagrams.Qualitatively indicated by different ramps are different time delays that occur during brake release and brake application, and are consequently also reflected in the displayed sensor signals. In the two lower diagrams, solid lines show the ramps that limit the range of permissible application delay and release delay, respectively. The steeper solid line and the flatter solid line indicate the tolerance range within which a change in the brake system is possible in the event of degradation of the entire brake mechanism.

[0095] braking behavior is still acceptable (all ramps in between are therefore also permissible, even if not shown).

[0096] The dashed ramps show examples of courses that must lead to an error signal according to the method according to the invention, since the application delay or release delay exceeds permissible limit values ​​and should therefore not be accepted during operation.

[0097] List of reference symbols

[0098] AT antenna

[0099] BKP brake heads

[0100] BRB brake pad

[0101] BST brake calipers

[0102] BUS bus system

[0103] BV braking device

[0104] CLD Cloud

[0105] DAK Digital Automatic Coupling

[0106] DG bogie

[0107] ERR error signal

[0108] Fb braking force

[0109] Fn normal force

[0110] FR direction of travel

[0111] FZ vehicle DG bogie RD wheel AC axle FL fixed bearing ZSS push-pull rod BRG brake linkage AKT actuator BRB brake pad

[0112] STE Actuator DA Rotary axis HL Main air line LC Locomotive GGSN Pressure sensor

[0113] GSN1 ... GSN3 first to third pressure sensors

[0114] DSN1 First pressure sensor DSN2 Second pressure sensor RBS Reference acceleration sensor AE Output device PR Processor ZPR Central processor SE Storage device ZSE Central storage device

[0115] S1 ... S8 interface

[0116] BUS bus line CP computer RW? Query step reference value available?

[0117] CAL IB Calibration step UNLOCK Brake deactivation step CALC Calculation step LOCK Brake activation step SET Determination step

[0118] TEST test step OUTPUT output error signal

[0119] FZV Vehicle Association

[0120] GHS housing

[0121] GL track

[0122] HL main air line

[0123] KKP ball heads

[0124] LAG length compensation

[0125] LST bearing rods

[0126] ME1 first measurement result

[0127] ME2 second measurement result

[0128] RWA Investment-related reference value

[0129] RWL Solvent-related reference value

[0130] TE1 first sub-unit

[0131] TE2 second sub-unit

[0132] ZPR Central Processor

[0133] ZSE Central Storage Device L1 ... L4 Line

[0134] RV Reservoir

[0135] BZL1 ... BZL2 brake cylinder

[0136] BSV brake control valve

[0137] AAN creation request

[0138] LAN release request

[0139] BP braking period

[0140] NO Upper Level

[0141] NU Lower Level

Claims

Patent claims 1. A method for carrying out a brake test in a convoy (FZV) of track-guided vehicles (FZ), in which a measured value describing the braking condition is generated in each vehicle using at least one sensor and this value is compared with at least one predetermined reference value in a computer-aided manner, characterized in that a) the time required to apply the brakes in each vehicle (FZ) of the convoy (FZV) is measured by determining the time difference between a time of an application request to apply the brakes and a time at which an application-related reference value is reached, b) an error signal (ERR) is generated if the time required to apply the brakes exceeds a predetermined application-related maximum value (AMX), and / or c) the time required until the brakes are released is measured in each vehicle of the convoy,by determining the time difference between a time of a release request to release the brakes and a time at which a release-related reference value is reached, d) an error signal (ERR) is generated if the time required to release the brakes exceeds a predetermined release-related maximum value (LMX).

2. Method according to claim 1, characterized in that a pressure sensor (DSN1, DSN2) measures the pressure prevailing in a pneumatic actuator system.

3. Method according to claim 2, characterized in that the one pressure sensor as the first pressure sensor (DSN1) measures the pressure prevailing in a main air line.

4. Method according to claim 2, characterized in that in each vehicle a first pressure sensor (DSN1) measures the pressure prevailing in the main air line.

5. Method according to claim 3 or 4, characterized in that in each vehicle a second pressure sensor (DSN2) measures the pressure prevailing in an actuator in the form of a pneumatic cylinder designed as the first brake cylinder (BZL1) for actuating the brake.

6. Method according to claim 5, characterized in that in each vehicle a third pressure sensor (DSN3) measures the pressure prevailing in an actuator in the form of a pneumatic cylinder designed as a second brake cylinder (BZL2) for actuating the brake.

7. Method according to one of the preceding claims, characterized in that one of the sensors is a geometry sensor (GSN) which measures a geometric state variable in the brake mechanism or is a force sensor which measures a force occurring in the brake linkage.

8. Method according to one of the preceding claims, characterized in that an application command for the brake is used as the time of the application request and / or a release command for the brake is used as the time of the release request.

9. Vehicle (FZ) which can be coupled with other vehicles (FZ) to form a track-guided vehicle convoy (FZV), e) with at least one sensor which can generate a measured value describing the braking condition, f) with a computing environment (RU) which is set up to compare the measured value with at least one predetermined reference value in a computer-aided manner, characterized in that the computing environment (RU) is also set up to carry out the two steps a) and b) and / or the two steps c) and d) according to claim 1.

10. A computer program product containing program instructions that can be executed by a computer, such that the method is carried out computer-aided according to one of claims 1-8.

11. A computer-readable storage medium containing data stored as data sets by the storage medium such that the data sets make the computer program product according to the last preceding claim executable.

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