Method and device for monitoring and influencing the thermal state of a friction brake system of a rail vehicle

Description

[0001] The invention relates to a method and a device for monitoring and influencing the thermal state of a friction braking system of a rail vehicle, according to the preamble of claims 1 and 10. The invention also relates to a rail vehicle with such a device according to claim 21.

[0002] Rail vehicles often have an electrodynamic braking system and an additional friction braking system, which interact according to specific criteria (blending). The electrodynamic brakes are primarily used to reduce wear on the friction braking system. Some rail vehicles have a friction braking system but no electrodynamic brakes. Therefore, in the event of a complete or partial failure of the electrodynamic brakes, braking, especially service braking, may have to be carried out mainly or exclusively using the friction braking system. The greater the vehicle weight being braked by the friction braking system and the higher the braking speed of the rail vehicle (i.e., the higher the speed at which friction braking begins), the greater the energy input and thus the temperature increase of the brake discs and brake pads.As a consequence, the fluctuation in the coefficient of friction µ of the brake disc-brake pad pair increases, and thus the probability that the coefficient of friction µ will decrease. At high braking speeds, there is therefore a risk that braking distances will increase due to brake fade. Brake fade (or brake fade) refers to the reduction in the braking effect of a friction braking system due to factors such as heat or moisture. To prevent brake fade due to heat, the maximum speed of the rail vehicle is limited by a maximum permissible speed, depending on the situation.

[0003] According to WO 2009 / 074265 A1, a method for controlling the drive and braking force of a vehicle is described. This method uses predetermined maximum permissible temperature changes for the wheel and rail—corresponding to the maximum permissible temperature changes below which no damage to the wheel or rail should occur—to calculate target frictional forces. From these target frictional forces, a target wheel slip is determined, from which a target braking force is then calculated. This braking force is then used to control or regulate the braking force. These measures are intended to increase the available slip-dependent traction.

[0004] The generic WO 2018 / 054736 A1 proposes a method and a device for influencing the kinematic behavior of a vehicle, comprising at least one friction braking system in which a braking effect is generated by pressing against each other at least a first friction element and a second friction element, wherein at least temperatures of at least the first friction element are calculated from information about a speed, a brake pressure and an outside temperature of the vehicle as well as about absolute times, and wherein heat conduction through the at least first friction element as well as speed-dependent cooling of the at least first friction element are taken into account in this calculation, and wherein the kinematic behavior of the vehicle is influenced on the basis of this calculation.

[0005] The present invention aims to provide a method and a device that, on the one hand, offers greater protection against overheating of the friction braking system, but on the other hand, enables the highest possible speed of the rail vehicle, i.e., driving "at the limit". Likewise, a rail vehicle equipped with such a device is to be provided.

[0006] This problem is solved according to the invention by the features of claims 1, 10 and 21. Disclosure of the invention

[0007] The background to the inventive considerations is that, during operation or while the rail vehicle is in motion, it should be ensured at all times that a defined braking type with a defined braking effect, such as an emergency, forced, or rapid brake application, can be carried out without the friction element temperature (e.g., brake disc temperature) reaching a critical range due to the resulting temperature rise dT. For this reason, the calculation or estimation of the first temperature component Tcurrent of the predictive friction element temperature Tpred, preferably carried out continuously during travel, always, constantly, or intermittently also takes into account the temperature rise dT resulting from a defined braking type, such as an emergency, forced, or rapid brake application.The temperature rise dT caused by emergency braking is calculated, determined, or estimated as the second temperature component of the predictive friction element temperature Tpred and then taken into account when monitoring and influencing the thermal state of the friction braking system. Depending on the predictive friction element temperature Tpred, i.e., the sum of the first temperature component Tcurrent and the second temperature component dT, calculated or estimated based on a theoretical or hypothetical implementation of the defined braking type, the thermal state of the rail vehicle's friction braking system is then monitored and influenced.

[0008] The thermal state can be influenced directly, by means of an intervention signal, or indirectly, for example by a driver or train conductor of the rail vehicle in response to a corresponding warning or indicator signal. This could involve, for instance, reducing the speed and / or deceleration of the rail vehicle in the event of an imminent (potential) overheating of the friction braking system, in order to lower the potential thermal load on the system. Therefore, the thermal state of the friction braking system is preferably influenced by adjusting or changing the speed and / or deceleration of the rail vehicle.

[0009] According to a first aspect, the invention relates to a method for monitoring and influencing the thermal state of a friction braking system of a rail vehicle depending on a calculated or estimated predictive friction element temperature T pred of at least one friction element of the friction braking system, comprising at least the following steps: a) Recording at least one parameter that characterizes a current operating situation of the rail vehicle, b) Calculating, estimating or determining a first temperature component T current of the predictive friction element temperature T pred based on the current operating situation of the rail vehicle and taking the first temperature component T current into account when monitoring and influencing the thermal state of the friction brake system.

[0010] Preferably, the parameter and / or characteristic value for characterizing the current driving situation is not a temperature value, i.e., the first temperature component is preferably not measured by a temperature sensor. For example, the first temperature component T current of the predictive friction element temperature T pred is estimated or calculated using a model from the at least one parameter.

[0011] Alternatively, at least one temperature sensor can be used to (directly) detect the first temperature component.

[0012] The term "rail vehicle" here refers to any type of track-bound vehicle with a drive motor, in particular locomotives, or even without a drive motor, such as...

[0013] The term can refer to wagons in rail vehicle units as well as a rail vehicle unit consisting of several rail vehicles.

[0014] According to the invention, the first aspect provides that c) when monitoring and influencing the thermal state of the friction brake system, a second temperature component dT of the predictive friction element temperature T pred is additionally taken into account, which would occur in addition to the first temperature component T current at the at least one friction element under the assumption that in the current operating situation of the rail vehicle, braking with a defined braking type is (additionally) carried out fictitiously or theoretically, and that d) the predictive friction element temperature T pred of the at least one friction element is determined as the sum of the first temperature component T current and the second temperature component dT, and that e) if the predictive friction element temperature T pred is greater than the permissible maximum friction element temperature T max of the at least one friction element, a first signal is generated which represents a potentially thermally critical state of the at least one friction element.and otherwise no initial signal is generated.

[0015] The generation of the first signal therefore indicates a potentially critical thermal state of at least one friction element. Potentially critical because this is based on the assumption that, in the current driving situation, braking with the defined braking method is only performed fictitiously or theoretically. Therefore, when the first signal is generated, the "thermal load potential" of at least one friction element of the friction braking system is potentially exhausted.

[0016] In the other case, i.e., if the predictive friction element temperature T pred is less than or equal to the allowable friction element maximum temperature T max of the at least one friction element, no first signal is generated or the generation of the first signal is suppressed, because it has then been found that there is no potentially critical thermal state of the at least one friction element.

[0017] Generating the first signal can also be equivalent to suppressing a signal, which in particular indicates a non-critical thermal state of the at least one friction element as a preset signal.

[0018] The method aims to ensure that a defined braking action, such as an emergency stop, can be performed at any point during a rail vehicle's journey without causing the predictive friction element temperature Tpred of at least one friction element to exceed the permissible maximum friction element temperature Tmax. The additional temperature rise resulting from the defined braking action, in the form of the second temperature component dT, is therefore taken into account when monitoring and controlling the thermal state of the friction braking system. In other words, even before the defined braking action is actually executed, an estimate or calculation of the second temperature component dT is preferably performed at any given time and / or continuously during the journey, in order to predict the predictive friction element temperature Tpred under the assumption (predictive approach) that the defined braking action will be performed.However, it is not absolutely necessary that the defined braking method is actually applied concurrently with the current operating situation. The estimation or calculation of the second temperature component, dT, is performed solely for safety reasons, to prevent thermal overload of at least one friction element of the friction braking system at any point during a journey, without requiring that the defined braking method is actually executed. The initial situation is therefore the current operating situation, in which the rail vehicle travels at a specific speed and load, under specific environmental and track conditions, along a route that is, for example, level or has a specific gradient or incline. Parameters such as speed, load, gradient, and incline are then recorded.The current driving situation may also include the possibility that a service brake has already been applied, deviating from the defined braking type, in which case the current brake pressure, braking force, and / or braking torque are recorded as parameters. Alternatively, no braking may be applied in the current driving situation, in which case the parameters relating to the current brake pressure, braking force, and / or braking torque are zero. Another alternative is that braking with a defined braking type may already be in progress or have already occurred in the current driving situation.

[0019] Based on the current actual operating situation and the parameters directly or indirectly recorded, the first temperature component Tcurrent of the predictive friction element temperature Tpred is calculated or estimated using a model based on the current operating situation of the rail vehicle, or alternatively or additionally, recorded by at least one temperature sensor. This first temperature component Tcurrent then corresponds to the temperature that actually occurs at the at least one friction element due to the current operating situation.

[0020] Additionally, the second temperature component dT of the predictive friction element temperature T pred is taken into account. This component is calculated or estimated using the model and would be present at the at least one friction element of the friction braking system in addition to the first temperature component T current if, in the current operating situation of the rail vehicle, braking with a defined braking type were fictitiously performed. This braking type has not yet been requested in the current operating situation, but could be requested in the current operating situation. The first temperature component T current is preferably calculated continuously, even if a specific braking type is currently being performed. dT, as the second temperature component, is the additional temperature rise, which is, for example, speed- and / or deceleration-dependent.Therefore, if an emergency stop is actually initiated, the first temperature component T current increases, while on the other hand the second temperature component dT decreases, and thus the maximum speed decreases.

[0021] The predictive friction element temperature Tpred of the at least one friction element of the friction braking system is then determined as the sum of the first temperature component Tcurrent and the second temperature component dT. This predictive friction element temperature Tpred would therefore theoretically or hypothetically be estimated or calculated to occur at or within the at least one friction element when the defined braking mode is executed in the current driving situation.

[0022] Since a rail vehicle typically has several friction brakes – for example, in the form of disc brakes and / or block brakes – the friction brake subjected to the highest thermal load can, as the (thermally) weakest link, serve as the benchmark for determining the optimal or maximum permissible speed of the rail vehicle. Each pair of friction elements installed in a train will preferably determine its own local Tpred temperature. This results in n locally determined Tpred temperatures. In this case, an algorithm should be implemented at higher train control levels that draws the correct conclusions from these n values ​​through consolidation and sends the appropriate instructions to the driver or an automated driving system.

[0023] For example, the mean could be calculated from all locally determined T pred values, and if the mean <T max ist, darf der Zug schneller fahren. Nach einem alternativen Algorithmus können im Sinne einer Maximalwertbetrachtung auch "Ausreißer" nach oben und unten im Rahmen der Konsolidierung aus der weiteren Berechnung entfernt werden.

[0024] Advantageous further developments of the invention specified in claim 1 are possible in the dependent claims.

[0025] As already indicated above, the defined braking type includes at least one of the following braking types: an emergency brake, a forced brake, a rapid brake, an emergency brake.

[0026] According to DIN EN 14478:2005-06, these brake types are defined as follows: Emergency braking Applying a predefined braking force using all available brakes, achieving the required braking performance and the required

[0027] Safety level guaranteed. The braking performance and safety level of the emergency braking described in vehicle-specific European Standards (EN) are, provided that the required traction and other necessary conditions are met, usually equal to or greater than the corresponding values ​​of a maximum service brake (full brake). In German, the term can vary depending on the specific train type or transport system and the method of emergency braking activation, as explained below: Emergency braking Emergency braking initiated by the train driver; Emergency braking Rapid braking in public transport braking systems; Emergency braking Emergency braking, which is automatically activated by signals or protection systems (e.g. train control systems); Emergency braking Emergency braking is triggered by passengers or train staff by pulling an emergency brake handle. The emergency brake handle is the operating interface of a passenger alarm system. Emergency braking highest achievable level of service braking Emergency braking Specifically designed for urban transport braking systems, this braking system provides a higher level of safety than service and emergency braking. The braking performance may be lower than with maximum service braking or emergency braking. Service braking Applying an adjustable braking force to regulate the speed of a train, including reducing speed, stopping and temporarily halting, and it is the most commonly used type of braking.

[0028] As stated above, the parameter(s) that characterize the current operating situation can be at least one of the following: the current speed of the rail vehicle, the current braking force, the current braking torque, the current brake pressure, the ambient temperature of the rail vehicle, the current load and / or cargo of the rail vehicle, an incline or decline of the track traversed by the rail vehicle, service braking, or operational braking with a braking effect that is less than that of the defined braking mode. This list is not exhaustive. Furthermore, other parameters are conceivable that can characterize the current operating situation of a rail vehicle, such as the coefficient of friction between the wheels and the rails.

[0029] Preferably, at least one friction element of the friction braking system can include a brake disc and / or a brake pad of a disc brake within the friction braking system. Alternatively, other friction brakes are also possible, such as block brakes.

[0030] Particularly preferably, if it turns out that the predictive friction element temperature T pred is greater than the permissible maximum friction element temperature T max of the at least one friction element, the first signal can a) represent a warning signal which is output optically and / or acoustically via an output unit and which represents or includes an indication of the potentially thermally critical state of the at least one friction element, and / or b) represent a first control signal which is output to at least one control unit of the rail vehicle which controls or regulates the traction and / or the braking of the rail vehicle, and by which the speed v of the rail vehicle and / or the deceleration a of the rail vehicle is reduced until the predictive friction element temperature T pred is less than or equal to the permissible maximum friction element temperature T max of the at least one friction element.

[0031] The warning signal can, for example, be issued to a train driver so that they reduce the speed and / or deceleration. Alternatively or additionally, the speed and / or deceleration of the train can be automatically reduced based on the initial control signal, for example by a control unit.

[0032] In the other case, if it turns out that the predictive friction element temperature T pred is smaller than the permissible maximum friction element temperature T max of the at least one friction element, a second signal can be generated which represents a thermally non-critical state of the at least one friction element.

[0033] The second signal can then be used in particular a) represent a warning signal, which is output visually and / or audibly via an output unit and which indicates that the current speed of the rail vehicle can be maintained or increased, and / or b) represent a second control signal, which is output to at least one control unit of the rail vehicle that controls or regulates the traction and / or braking of the rail vehicle, and by which the speed v of the rail vehicle and / or the deceleration a of the rail vehicle is increased until the predictive friction element temperature T pred is equal to the permissible maximum friction element temperature T max of the at least one friction element. To automatically increase the current speed, further factors usually need to be taken into account.For example, there might be speed limits due to the route, or the train might be entering a station, or the speed might not be allowed to increase on a downhill stretch.

[0034] The warning signal can, for example, be issued to a train driver so that they maintain or, preferably, increase the speed and / or deceleration, provided this is possible due to operational constraints, such as track-related speed limits. Alternatively or additionally, the speed and / or deceleration of the rail vehicle can also be automatically maintained or, preferably, increased based on the first control signal.

[0035] In this case, the "thermal load potential" of at least one friction element of the friction braking system is therefore not yet fully exhausted, so that the speed and / or deceleration of the rail vehicle can be increased for purely thermal reasons. From this perspective, an ideal speed and / or deceleration is one at which the predictive friction element temperature Tpred corresponds to the permissible maximum friction element temperature Tmax of the at least one friction element.

[0036] A further thermally critical state of the at least one friction element exists if the first temperature component Tcurrent of the predictive friction element temperature Tpred alone, i.e., without including the second temperature component dT, is greater than the permissible maximum friction element temperature Tmax of the at least one friction element. In this case, a third signal is preferably generated.

[0037] The third signal can a) represent a warning signal which is output optically and / or acoustically via an output unit and which represents or includes an indication of a thermally critical state of the at least one friction element, and / or b) represent a third control signal which is output to at least one control unit of the rail vehicle which controls or regulates the traction and / or the braking of the rail vehicle, and by which the speed v of the rail vehicle and / or the deceleration a of the rail vehicle is reduced until the first temperature component T current is less than or equal to the permissible maximum friction element temperature T max of the at least one friction element.

[0038] The warning signal can then be issued to a train driver, for example, so that they reduce the speed and / or deceleration. Alternatively or additionally, the speed and / or deceleration of the train can be automatically reduced based on the third control signal, for example by a control unit.

[0039] According to a second aspect, the invention relates to a device for monitoring and influencing the thermal state of a friction brake system of a rail vehicle depending on a predictive friction element temperature T pred of at least one friction element of the friction brake system, calculated or estimated at least partially by means of a model, which comprises at least the following: a) Detection means configured to detect at least one parameter characterizing a current operating situation of the rail vehicle, b) a computing unit configured for monitoring and influencing the thermal state of the friction brake system and in which the model is implemented, wherein c) the detection means input the at least one parameter into the computing unit, and wherein d1) the model performs calculations such that it calculates or estimates a first temperature component T current of the predictive friction element temperature T pred based on the at least one parameter, and / or wherein d2) the detection means are configured to detect the first temperature component T current of the predictive friction element temperature (T pred) and input it into the model, and wherein e) the computing unit orThe model is designed to take into account the first temperature component T current when monitoring and influencing the thermal state of the friction brake system.

[0040] A model is understood to be any physical-mathematical model that can be implemented by a storable program in a computing unit and with whose help the aforementioned quantities can be calculated based on the parameters.

[0041] The second aspect is characterized according to the invention in that f) the model further performs calculations such that, when monitoring and influencing the thermal state of the friction brake system, an additional second temperature component dT of the predictive friction element temperature T pred is taken into account, which the model calculates or estimates and which, in addition to the first temperature component T current, would occur at the at least one friction element under the assumption that, in the current operating situation of the rail vehicle, braking with a defined braking type is fictitiously or theoretically carried out, and wherein g) the model further performs calculations such that the predictive friction element temperature T pred of the at least one friction element is determined as the sum of the first temperature component T current and the second temperature component dT, and that h) the computing unit is configured to generate a first signal on the basis of the model's calculations,which represents a potentially thermally critical state of the at least one friction element if the model determines that the predictive friction element temperature Tpred is greater than the allowable maximum friction element temperature Tmax of the at least one friction element, and otherwise does not generate a first signal.

[0042] The technical effects of the device according to the invention correspond to the technical effects of the method according to the invention described above.

[0043] The invention also relates to a rail vehicle with a device described above. drawing

[0044] Exemplary embodiments of the invention are shown in the drawing below and explained in more detail in the following description. The drawing shows Fig. 1 a schematic representation of an exemplary embodiment of a pneumatic friction braking device with a brake disc and a brake caliper with brake linings; Fig. 2 a functional diagram of an exemplary embodiment of a device according to the invention for an embodiment of the method according to the invention; Fig. 3A / Beine flow diagram of the method according to the invention according to a preferred embodiment; Fig. 4 a diagram in which the dependence of a second temperature component dT on the driving speed v and load condition is shown. Description of the exemplary implementations

[0045] A in Fig. 1A schematically represented section of a friction braking system of a rail vehicle shows a pneumatic disc brake. This comprises a first friction element 1, which is designed, for example, as a brake disc, mounted on a wheelset axle (not shown) of the rail vehicle, and a brake caliper. The brake caliper has a second friction element 2, which comprises two brake pads. Furthermore, the brake caliper has a brake cylinder 4 with compressed air connections 6, a piston 5, and a linkage 3. The piston 5 actuates the linkage 3, thereby pressing the brake pads arranged on the linkage 3, i.e., the second friction element 2, against the brake disc, i.e., the first friction element 1. The piston 5 is supplied with compressed air from a compressed air system (not shown) of the rail vehicle via the compressed air connections 6 to actuate the linkage 3.The compressed air system includes components for controlling and regulating the friction braking system, such as compressors, brake control units, etc.

[0046] A preferred embodiment of a device for influencing the kinematic behavior of the rail vehicle has a Fig. 2 The illustrated computing unit 7 contains a model that performs thermal calculations according to the method according to the invention.

[0047] The device comprises a Fig. 2 The control unit 8 shown, with which the kinematic behavior of the rail vehicle is influenced based on the results of the thermal calculations.

[0048] Pressing the first friction element 1 and the second friction element 2 against each other causes a braking effect on the rail vehicle. This results in the conversion of the rail vehicle's kinetic energy into heat, causing a temperature increase in both the first and second friction elements. Separating the first and second friction elements 1 from each other reduces or eliminates the braking effect on the rail vehicle. This, along with the action of known heat transfer principles, reduces the temperatures in both the first and second friction elements 1, i.e., they cool down. The described temperature behavior is calculated or estimated using the method according to the invention.

[0049] The device comprises a speed sensor 10 for detecting a travel speed v, a brake pressure sensor 11 for detecting a brake pressure p and thus a braking force FB, an ambient temperature sensor 12 for detecting an ambient temperature Tu, a timer 13 for detecting an absolute time t, and a load-dependent braking device 14, which are connected via corresponding data lines to a processing unit 7 in order to provide the sensor signals to the model. The speed sensor 10, the brake pressure sensor 11, and the ambient temperature sensor 12 are arranged in a chassis of the rail vehicle (not shown). However, it is also conceivable that the travel speed v and the brake pressure p are read into the processing unit 7 from a data bus system of the rail vehicle. Furthermore, it is also conceivable that the brake pressure p is approximated from a deceleration and a mass to be braked.The deceleration is calculated, for example, by differentiating the vehicle speed v or determined via acceleration sensors, and the mass m to be decelerated is determined via a load-braking device 14. Furthermore, it is also conceivable that instead of a vehicle speed v, an angular velocity of a wheel or a wheel rotational speed is recorded, and the thermal calculations are performed using this angular velocity or wheel rotational speed. Additionally, configuration data of the rail vehicle is stored in a memory of the computing unit 7 (not shown here) and is also available to the model. This memory also stores a permissible maximum friction element temperature Tmax, for example, of the first friction element 1.

[0050] The timing device 13 and the processing unit 7, implemented in a control unit (not shown), are arranged in a car body (not shown). The processing unit 7 receives data via corresponding data lines from the vehicle speed sensor 10 regarding the vehicle speed v, from the brake pressure sensor 11 regarding the brake pressure p or braking force FB, from the ambient temperature sensor 12 regarding the ambient temperature Tu, from the load-braking device 14 regarding the vehicle mass m, and from the timing device 13 regarding the absolute time t (timestamp), and performs calculations according to the method according to the invention. Furthermore, configuration data of the rail vehicle stored in the memory of the processing unit 7 can also be incorporated into the calculations of the model.

[0051] Here, for example, using the travel speed v, the braking force FB, the ambient temperature Tu, the absolute time t, the mass m and the configuration data of the rail vehicle, the following are calculated according to the description: Fig. 3A and 3B thermal states of the in Fig. 1 The friction braking device shown is determined, in particular from its first friction element 1.

[0052] The computing unit 7 is connected via corresponding data lines to a control unit 8, implemented in a vehicle control system (not shown) and located in the car body. The control unit 8 influences the kinematic behavior of the rail vehicle in such a way that, for example, the rail vehicle maintains its current speed v, is automatically braked, or accelerated by signals generated in the model implemented in the computing unit 7 based on a thermal calculation and transmitted to the control unit 8. Braking can preferably be achieved by controlling the traction, so as not to increase the brake disc temperature and wear through the application of the friction brake. This allows for influencing the thermal state of the friction brake system.

[0053] Furthermore, a display unit 9, connected to the processing unit 7 via a signal line, is arranged in a driver's cab of the rail vehicle (not shown). This unit displays information or warnings to the train driver based on thermal calculations according to the inventive method described below. This allows monitoring of the thermal condition of the friction brake system.

[0054] It is also possible for the display unit 9 to additionally display speed limits, permissible decelerations or permissible driving profiles (time sequences of acceleration and deceleration sections as well as phases with constant driving speed v or phases of standstill).

[0055] To warn of unfavorable kinematic behavior of the rail vehicle with regard to thermal conditions of the friction braking system, additional acoustic signals can be output to the train driver via an audio output device of the display unit 9.

[0056] Various designs and arrangements of the vehicle speed sensor 10, the brake force sensor 11, the ambient temperature sensor 12, the timer 13, the display unit 9, the processing unit 7, the load braking device 14, and the control unit 8 are conceivable. For example, it is conceivable, as in Fig. 2 It has been shown to arrange the computing unit 7 and the control unit 8 separately, or to integrate the computing unit 7 and the control unit 8 into one unit.

[0057] Furthermore, it is also conceivable that, for example, the computing unit 7 is arranged in a control room and communicates with the rail vehicle via radio signals, i.e., for example, receives information about its travel speed v and, based on a thermal calculation carried out according to the invention, sends instructions to limit the travel speed v.

[0058] Fig. 3A and 3B Figure 1 shows a flow chart of a preferred embodiment of the inventive method for monitoring and influencing the thermal state depending on a calculated or estimated predictive friction element temperature T pred, for example of the first friction element 1 in the form of the brake disc of the disc brake.

[0059] As described above, 100 parameters are recorded in one step, characterizing the current operating situation of the rail vehicle. These include, for example, the current speed v, the current braking force FB, the current ambient temperature T u, data regarding absolute time t (timestamp), the current mass m of the rail vehicle, and the configuration data of the rail vehicle.

[0060] In the model of computing unit 7, a first temperature component Tcurrent of the predictive friction element temperature Tpred, for example of the first friction element 1, is calculated or estimated in step 200, based on the current operating conditions of the rail vehicle mentioned above. Alternatively or additionally, the first temperature component Tcurrent can also be measured directly by a temperature sensor. The first temperature component Tcurrent then corresponds, for example, to the surface temperature calculated or estimated by the model, which results from the actual current operating conditions on the surface of the first friction element 1.

[0061] In a subsequent step 300, the model checks whether the first temperature component T current is greater than the permissible maximum friction element temperature T max of the first friction element 1. If this is the case ("yes"), the processing unit 7 generates, for example, an alarm or warning signal, which is then displayed visually on the display unit 9 and which, for example, indicates a critical thermal condition of the first friction element 1. Alternatively or additionally, an influence signal could also be generated, which is output to the control unit 8, which controls the traction and / or the brake of the rail vehicle.The influence signal is then used, for example, to reduce the speed v and / or the deceleration a of the rail vehicle until the first temperature component T current is less than or equal to the permissible maximum friction element temperature T max of the first friction element 1.

[0062] However, if this is not the case ("no"), then in step 400 a second temperature component dT of the predictive friction element temperature T pred is calculated or estimated using the model implemented in the processing unit 7. This second temperature component dT is Fig. 3AThis is referred to as the temperature rise dT and would occur in addition to the first temperature component T current at the surface of the first friction element 1 if, in the current operating situation of the rail vehicle, braking with a defined braking type were fictitiously or theoretically carried out. This defined braking type has not yet been requested in the current operating situation, but could be requested in the current operating situation.

[0063] The second temperature component dT of the predictive friction element temperature T pred depends in particular on the driving speed v, which is present in the current driving situation at time t (timestamp). Fig. 4The diagram, which is stored, for example, in a characteristic map in processing unit 7, shows the dependence of the second temperature component dT on the driving speed v for various load cases, such as AW1: low load, AW2: medium load, and AW3: high load. Of course, other load cases can also be considered in the characteristic map. As can be seen, the second temperature component dT increases with increasing driving speed v, which (also) characterizes the current driving situation. Consequently, the diagram illustrates... Fig. 4 A specific second temperature component dT of the predictive friction element temperature T pred is assigned in a characteristic-map-like manner to the driving speed v and load of the rail vehicle present in the current driving situation.

[0064] Then, in step 500, the predictive friction element temperature T pred is determined, for example, as the surface temperature of the first friction element 1 as the sum of the first temperature component T current and the second temperature component dT: T pred = T current + dT

[0065] In step 600, it is then checked whether the predictive friction element temperature Tpred is greater than the permissible maximum friction element temperature Tmax of the first friction element 1. If this is the case ("yes"), the processing unit 7 generates a warning signal, which is then displayed visually on the display unit 9 and which, for example, indicates a critical thermal condition of the first friction element 1. Alternatively or additionally, an intervention signal could also be generated, which is then output to the control unit 8, which controls the traction and / or the brakes of the rail vehicle. Using the intervention signal, the speed v and / or the deceleration a of the rail vehicle is then reduced, for example, until the predictive friction element temperature Tpred is equal to the permissible maximum friction element temperature Tmax of the first friction element 1.This represents an ideal state to be strived for, because then the "thermal load potential" of the first friction element 1 is fully exploited.

[0066] If this is not the case ("no"), step 700 checks whether the predictive friction element temperature Tpred is (already) lower than the permissible maximum friction element temperature Tmax of the first friction element 1. If this is the case ("yes"), any previously generated warning signal is reset or no warning signal is generated. However, the speed v of the rail vehicle could be increased solely based on the thermal state of the first friction element 1. Therefore, if other conditions, such as the timetable or traffic situation, permit, the speed v could be increased until the predictive friction element temperature Tpred corresponds to the permissible maximum friction element temperature Tmax of the first friction element 1. For this reason, in the case of "yes," the processing unit 7 generates an influence signal and feeds it into the control unit 8 so that it can adjust the traction or...controls or regulates the propulsion of the rail vehicle in order to increase the speed v accordingly.

[0067] However, if the query in step 700 indicates that this is not the case ("no"), then in step 800 only the ideal state described above exists from a thermal perspective, in which the predictive friction element temperature Tpred corresponds to the permissible maximum friction element temperature Tmax of the first friction element 1. In this case, therefore, no adjustment of the speed v is necessary.

[0068] It is clear that the procedure described above can also be applied to the second friction element 2 of the disc brake or additionally. Reference symbol list

[0069] 1. First friction element 2. Second friction element 3. Linkage 4. Brake cylinder 5. Piston 6. Compressed air connections 7. Calculation unit 8. Control unit 9. Display unit 10. Vehicle speed sensor 11. Brake pressure sensor 12. Ambient temperature sensor 13. Time instrument 14. Load braking device T current first temperature component dT second temperature component T pred predictive friction element temperature T max permissible maximum friction element temperature v vehicle speed m vehicle mass FBB braking force Tu ambient temperature t time

Claims

1. A method for monitoring and influencing the thermal state of a friction brake system of a rail vehicle dependent on a calculated or estimated predictive friction element temperature (Tpred) of at least one friction element (1, 2) of the friction brake system, including at least the following steps: a) detecting at least one parameter which characterizes a current operating situation of the rail vehicle, b) calculating, estimating or determining a first temperature component (Tcurrent) of the predictive friction element temperature (Tpred) on the basis of the current operating situation of the rail vehicle and taking the first temperature component (Tcurrent) into consideration when monitoring and influencing the thermal state of the friction brake system, characterized in that c) the monitoring and influencing of the thermal state of the friction brake system additionally takes into consideration a second temperature component (dT) of the predictive friction element temperature (Tpred), which would be obtained in addition to the first temperature component (Tcurrent) at the at least one friction element (1, 2) on the assumption that, in the current operating situation of the rail vehicle, braking with a defined type of braking is notionally or theoretically carried out, and in that d) the predictive friction element temperature (Tpred) of the at least one friction element (1, 2) is determined as the sum of the first temperature component (Tcurrent) and the second temperature component (dT), and in that e) if the predictive friction element temperature (Tpred) is greater than the allowed friction element maximum temperature (Tmax) of the at least one friction element (1, 2), a first signal is generated, representing a potentially thermally critical state of the at least one friction element (1, 2), and otherwise a first signal is not generated.

2. The method as claimed in claim 1, characterized in that the defined type of braking comprises at least one of the following types of braking: emergency braking, forced braking, rapid braking, hazard braking.

3. The method as claimed in one of the preceding claims, characterized in that the first signal a) represents a warning signal, which is optically and / or acoustically output by way of an output unit and which represents or comprises an indication of the potentially thermally critical state of the at least one friction element (1, 2), and / or b) represents a first influencing signal, which is output to at least one controller of the rail vehicle, which controls the traction and / or the brake of the rail vehicle in an open-loop or closed-loop manner, and by which the running speed (v) of the rail vehicle and / or the deceleration (a) of the rail vehicle is reduced until the predictive friction element temperature (Tpred) is less than or equal to the allowed friction element maximum temperature (Tmax) of the at least one friction element (1, 2).

4. The method as claimed in one of the preceding claims, characterized in that, if the predictive friction element temperature (Tpred) is less than the allowed friction element maximum temperature (Tmax) of the at least one friction element (1, 2), a second signal is generated, representing a thermally uncritical state of the at least one friction element (1, 2).

5. The method as claimed in one of the preceding claims, characterized in that the second signal c) represents an indicating signal, which is optically and / or acoustically output by way of an output unit and which comprises an indication to the effect that a current speed of the rail vehicle can be maintained or increased from a thermal perspective, and / or d) represents a second influencing signal, which is output to at least one controller of the rail vehicle, which controls the traction and / or the brake of the rail vehicle in an open-loop or closed-loop manner, and by which the running speed (v) of the rail vehicle and / or the deceleration (a) of the rail vehicle is increased until the predictive friction element temperature (Tpred) is equal to the allowed friction element maximum temperature (Tmax) of the at least one friction element (1, 2).

6. The method as claimed in one of the preceding claims, characterized in that, if the first temperature component (Tcurrent) of the predictive friction element temperature (Tpred) alone is already greater than the allowed friction element maximum temperature (Tmax) of the at least one friction element (1, 2), a third signal is generated, representing a thermally critical state of the at least one friction element (1, 2).

7. The method as claimed in claim 6, characterized in that the third signal a) represents a warning signal, which is optically and / or acoustically output by way of an output unit and which represents or comprises an indication of the thermally critical state of the at least one friction element (1, 2), and / or b) represents a third influencing signal, which is output to at least one controller of the rail vehicle, which controls the traction and / or the brake of the rail vehicle in an open-loop or closed-loop manner, and by which the running speed (v) of the rail vehicle and / or the deceleration (a) of the rail vehicle is reduced until the first temperature component (Tcurrent) is less than or equal to the allowed friction element maximum temperature (Tmax) of the at least one friction element (1, 2).

8. The method as claimed in one of the preceding claims, characterized in that the parameter that characterizes the current operating situation is at least one of the following parameters: the current speed of the rail vehicle, the current braking force, the current braking torque, the current braking pressure, the ambient temperature of the rail vehicle, the current load and / or loading of the rail vehicle, an incline or a gradient of the section of track being run over by the rail vehicle, service braking or normal application of the brakes.

9. The method as claimed in one of the preceding claims, characterized in that the friction element (1, 2) comprises a brake disk and / or a brake lining of a disk brake of the friction brake system, or a wheel running surface and / or a brake shoe of a shoe braking unit of the friction brake system.

10. A device for monitoring and influencing the thermal state of a friction brake system of a rail vehicle dependent on a predictive friction element temperature (Tpred) of at least one friction element (1, 2) of the friction brake system at least partially calculated or estimated by means of a model, the device comprising at least the following: a) detecting means (10, 11, 12, 13), which are designed for detecting at least one parameter which characterizes a current operating situation of the rail vehicle, b) a computing unit (7), which is designed for monitoring and influencing the thermal state of the friction brake system and in which the model is implemented, and wherein c) the detecting means (10, 11, 12, 13) enter the at least one parameter into the computing unit (7), and wherein d1) the model carries out calculations in such a way that it calculates or estimates a first temperature component (Tcurrent) of the predictive friction element temperature (Tpred) on the basis of the at least one parameter, or wherein d2) the detecting means (10, 11, 12, 13) is designed so as to detect the first temperature component (Tcurrent) of the predictive friction element temperature (Tpred) and enter it into the model, and wherein e) the computing unit (7) is designed so as to take the first temperature component (Tcurrent) into consideration when monitoring and influencing the thermal state of the friction brake system, characterized in that f) the model also carries out calculations in such a way that the monitoring and influencing of the thermal state of the friction brake system additionally takes into consideration a second temperature component (dT) of the predictive friction element temperature (Tpred), which the model calculates or estimates, and which would be obtained in addition to the first temperature component (Tcurrent) at the at least one friction element (1, 2) on the assumption that, in the current operating situation of the rail vehicle, braking with a defined type of braking is notionally or theoretically carried out, and wherein g) the model also carries out calculations in such a way that the predictive friction element temperature (Tpred) of the at least one friction element (1, 2) is determined as the sum of the first temperature component (Tcurrent) and the second temperature component (dT), and in that h) the computing unit (7) is designed so as to generate, on the basis of the calculations of the model, a first signal, representing a potentially thermally critical state of the at least one friction element (1, 2), if it is established by the model that the predictive friction element temperature (Tpred) is greater than the allowed friction element maximum temperature (Tmax) of the at least one friction element (1, 2), and otherwise a first signal is not generated.

11. The device as claimed in claim 10, characterized in that the defined type of braking comprises at least one of the following types of braking: emergency braking, forced braking, rapid braking, hazard braking.

12. The device as claimed in either of claims 10 and 11, characterized in that the first signal a) represents a warning signal, which is optically and / or acoustically output by way of an output unit and which represents or comprises an indication of the potentially thermally critical state of the at least one friction element (1, 2), and / or b) represents a first influencing signal, which is output to at least one controller of the rail vehicle, which controls the traction and / or the brake of the rail vehicle in an open-loop or closed-loop manner, and by which the running speed (v) of the rail vehicle and / or the deceleration (a) of the rail vehicle is reduced until the predictive friction element temperature (Tpred) is less than or equal to the allowed friction element maximum temperature (Tmax) of the at least one friction element (1, 2).

13. The device as claimed in one of claims 10 to 12, characterized in that the computing unit (7) is designed so as to generate a second signal, representing a thermally uncritical state of the at least one friction element (1, 2), if it establishes that the predictive friction element temperature (Tpred) is less than or equal to the allowed friction element maximum temperature (Tmax) of the at least one friction element (1, 2).

14. The device as claimed in one of claims 10 to 12, characterized in that the second signal a) represents an indicating signal, which is optically and / or acoustically output by way of an output unit and which comprises an indication to the effect that the speed of the rail vehicle can be maintained or increased from a thermal perspective, and / or b) represents a first influencing signal, which is output to at least one controller of the rail vehicle, which controls the traction and / or the brake of the rail vehicle in an open-loop or closed-loop manner, and by which the running speed (v) of the rail vehicle and / or the deceleration (a) of the rail vehicle is increased until the predictive friction element temperature (Tpred) is equal to the allowed friction element maximum temperature (Tmax) of the at least one friction element (1, 2).

15. The device as claimed in one of claims 10 to 14, characterized in that the computing unit (7) is designed so as to generate a third signal, representing a thermally critical state of the at least one friction element (1, 2), if it establishes that the first temperature component (Tcurrent) of the predictive friction element temperature (Tpred) alone is already greater than the allowed friction element maximum temperature (Tmax) of the at least one friction element (1, 2).

16. The device as claimed in claim 15, characterized in that the third signal a) represents a warning signal, which is optically and / or acoustically output by way of an output unit and which represents or comprises an indication of the thermally critical state of the at least one friction element (1, 2), and / or b) represents a third influencing signal, which is output to at least one controller of the rail vehicle, which controls the traction and / or the brake of the rail vehicle in an open-loop or closed-loop manner, and by which the running speed (v) of the rail vehicle and / or the deceleration (a) of the rail vehicle is reduced until the first temperature component (Tcurrent) is less than or equal to the allowed friction element maximum temperature (Tmax) of the at least one friction element (1, 2).

17. The device as claimed in one of claims 10 to 16, characterized in that the parameter that characterizes the current operating situation is at least one of the following parameters: the current speed of the rail vehicle, the current braking force, the current braking torque, the current braking pressure, the ambient temperature of the rail vehicle, the current load and / or loading of the rail vehicle, an incline or a gradient of the section of track being run over by the rail vehicle, service braking or normal application of the brakes.

18. The device as claimed in one of claims 10 to 17, characterized in that the friction element (1, 2) comprises a brake disk and / or a brake lining of a disk brake of the friction brake system, or a wheel running surface and / or a brake shoe of a shoe braking unit of the friction brake system.

19. The device as claimed in one of claims 10 to 18, characterized in that the parameter that characterizes the current operating situation is at least one of the following parameters: the current speed of the rail vehicle, the current braking force, the current braking torque, the current braking pressure, the ambient temperature of the rail vehicle, the current load and / or loading of the rail vehicle, an incline or a gradient of the section of track being run over by the rail vehicle, service braking or normal application of the brakes.

20. The device as claimed in one of claims 10 to 19, characterized in that the rail vehicle comprises multiple friction brakes each with at least one friction element (1, 2), and in that a temperature-dependent running behavior is respectively ascertained as described above for each of the multiple friction brakes, but is consolidated over all the friction brakes on a train-wide level and the consolidated running instruction is passed on to the driver of the tractive unit or to a train control system.

21. A rail vehicle with a device as claimed in one of claims 10 to 20.