Brake system for at least one vehicle, and calibration system and method therefor

Abstract

Described is a braking system (200) for at least one vehicle (V), in particular at least one railway vehicle, comprising a control device arranged to: a) determine a true instantaneous deceleration value of the vehicle during actuation of a braking device (202); b) determining a real friction value between a braking device and at least one wheel or at least one disc as a function of at least the real instantaneous deceleration value, a test mass value of the vehicle and a value of an actuation signal; c) replacing the predetermined expected friction value stored in the storage medium (210, 210 ') with the determined true friction value. A system for calibrating a brake system of at least one vehicle and a method for calibrating a brake system of at least one vehicle (V), and a vehicle are further described.

Description

Technical Field

[0001] The invention generally pertains to the automotive industry; in particular, the invention relates to a braking system for at least one vehicle, a system for calibrating a braking system of at least one vehicle, and a method for calibrating a braking system in at least one vehicle. Background Art

[0002] The known technology will be described below mainly with reference to the field of automobile railways. However, the content described below can also be (similarly) applied to vehicles in other fields.

[0003] In braking systems for railway vehicles, it is a known technique to calibrate (tune) the braking parameters during dynamic field testing. This tuning is done before the vehicle is put into service.

[0004] The goal of tuning the braking parameters is to make the vehicle's braking performance meet the design performance requirements, such as average deceleration, instantaneous deceleration and stopping distance.

[0005] In particular, tuning relates to different types of braking: service braking, emergency braking, rescue braking and other possible types of braking using a braking system as a means of applying brakes in a railway vehicle.

[0006] For example, the braking system may be a pneumatic or electro-pneumatic braking system that can stop / decelerate the vehicle by actuating the brakes. Figure 1 As can be seen in the figure, the brake device 100 may include, for example, at least one brake application element, also referred to as a "friction lining". The brake application element may be, for example, a brake shoe 102 in the case of a system using a "shoe" brake, or a brake pad 104 in the case of a system using a "disc" brake.

[0007] The brake element can be appropriately pushed onto a specific element, such as the brake disc 106 in the case of a system using a "disc" brake, or the wheel W in the case of a system using a "shoe" brake, by means of pneumatic pressure acting on a piston that applies the braking force.

[0008] Such a brake element can be pushed onto a disc or a wheel by the aforementioned pneumatic pressure in order to generate a braking force by means of the known friction phenomenon caused by sliding between relatively moving bodies. The relatively moving bodies are thus, for example, a brake application element attached to a railway carriage, and a brake disc (in the case of a disc brake) or a wheel attached to a rotating railway axle 108.

[0009] One of the abovementioned braking parameters is in particular the friction value between the braking device and the wheel or disc.

[0010] In the known art, the tuning of this parameter is carried out by qualified and authorized personnel through manual modification, during dynamic testing of the vehicle, of the friction value resident in the brake software / control device. Similar tuning procedures for other brake parameters can also be envisaged. The aforementioned friction value between the brake device and the disc or wheel can also affect other brake parameters directly connected thereto.

[0011] It is known that the modification of said brake parameters has a direct effect on the brake pressure acting on the inside of a piston residing in a cylinder called the brake cylinder of the brake device. The piston, driven by said brake pressure, acts on a brake application element which is then pushed onto the discs or wheels of the railway vehicle, thereby generating a braking force which is responsible for slowing down and subsequently stopping the railway vehicle.

[0012] The aforementioned tuning of the braking parameters during dynamic testing of railway vehicles has the main limitation that a manual procedure is used by the supervisor in defining the braking parameters. The resulting impact is defined by the risk of human error due to the manual nature of the procedure and the increased time spent in tuning the braking parameters.

[0013] Additionally, calibration parameters should be reviewed over the life of the vehicle due to wear of the brakes. However, since the above tuning procedures are not automatic but require specific manual tests to be performed in the field, the vehicle must be removed from service if these brake parameters need to be recalibrated. Summary of the invention

[0014] The object of the present invention is to provide a solution that allows reducing the time needed to calibrate a braking parameter related to the friction value between a braking device and at least one wheel or at least one disc associated with a wheel or axle of a vehicle.

[0015] A further object of the invention is to provide a solution that reduces the time taken to calibrate braking parameters related to friction values ​​between a braking device and at least one wheel or at least one disc associated with a wheel or axle.

[0016] A further object of the invention is to provide a solution allowing automatic tuning of braking parameters related to the friction value between the braking device and at least one wheel or at least one disc associated with a wheel or axle, even after commissioning of the vehicle.

[0017] According to one aspect of the invention, these and other objects and benefits are achieved by a braking system having the characteristics according to claim 1, by a system for calibrating a braking system of at least one vehicle having the characteristics according to claim 12, by a method for calibrating a braking system of at least one vehicle having the characteristics according to claim 14, and by a vehicle having the characteristics according to claim 16 or 17. Preferred embodiments of the invention are defined in the dependent claims, the contents of which are to be understood as an integral part of the present description.

[0018] In summary, the present invention aims to replace, by an automatic solution, the manual procedure of tuning the braking parameters related to the friction value between the braking device and the wheel or the disc associated with the wheel or the axle. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The functional and structural features of some preferred embodiments of a braking system of at least one vehicle, a system for calibrating a braking system, a method for calibrating a braking system and a vehicle according to the present invention will now be described. With reference to the accompanying drawings, in which:

[0020] - Figure 1 An example of a braking device according to known technology is shown;

[0021] - Figure 2 A first embodiment of a braking system according to the invention is shown;

[0022] - Figure 3a and 3b A corresponding illustrative embodiment is shown wherein the brake device includes a plurality of brake applying devices;

[0023] - Figure 4 An illustrative disassembled condition C1 of the brake device and an illustrative contact condition C2 of the brake device are shown in detail;

[0024] - Figure 5 A further embodiment of the brake system according to the invention is shown;

[0025] - Figure 6 An embodiment of a system for calibrating a braking system is shown;

[0026] - Figure 7 Further embodiments of a system for calibrating a brake system are shown. DETAILED DESCRIPTION

[0027] Before explaining in detail the various embodiments of the present invention, it should be clarified that the present invention is not limited in its application to the construction details and configurations of the components presented in the following description or shown in the accompanying drawings. The present invention can adopt other embodiments and is actually implemented or realized in different ways. It should also be understood that the words and terms are descriptive and should not be interpreted as limiting. The use of "comprises" and "includes" and variations thereof is intended to include the elements and their equivalents set forth below, as well as additional elements and their equivalents.

[0028] First reference Figure 2 , a first exemplary embodiment of a braking system for at least one vehicle, in particular at least one rail vehicle, is described below.

[0029] In this first embodiment, the braking system 200 comprises a braking device 202 arranged to receive an actuation signal and to apply a corresponding braking force F to at least one wheel of the vehicle or to at least one disc associated with at least one wheel or axle of the vehicle.

[0030] The magnitude of the braking force F applied by the braking device 202 is a function of the value of the actuation signal 204 .

[0031] In other words, the intensity of the braking force F applied by the braking device 202 is a function of the value given by the actuation signal 204. For example, the greater the value given by the actuation signal 204, the greater the intensity of the braking force applied by the braking device, and vice versa.

[0032] The brake system 200 further includes a control device 205 .

[0033] For example, the control device 205 may be or include at least one of the following: a controller, a processor, a microprocessor, a microcontroller, at least one PLC, an FPGA, etc.

[0034] The control device 205 is arranged to:

[0035] - receiving a test brake request 206 indicating a desired instantaneous deceleration value;

[0036] - determining a value of an actuation signal 204 allowing the braking device 202 to apply to at least one wheel or at least one disc a braking force F having an intensity value such that at least one of said vehicles will decelerate according to said expected instantaneous deceleration value;

[0037] Actuating the braking device 202 in dependence on the determined value of the actuation signal 204 .

[0038] In other words, the determined value of the actuation signal 204 is a value that will cause the braking device 202 to apply a braking force F to at least one wheel or at least one disc having such an intensity value that at least one vehicle will decelerate according to the expected instantaneous deceleration value.

[0039] The control device 205 is arranged to determine the value of the actuation signal 204 based on at least a predetermined expected friction value between the braking device 202 and at least one wheel or at least one disc, using a test mass value of at least one vehicle 208, and using an expected instantaneous deceleration value.

[0040] The predetermined expected friction value between the braking device 202 and at least one wheel or one disc is arranged to be stored at a storage medium 210 comprised in the control device 205 or at a storage medium 210 ′ associated with the control device 205 .

[0041] The control device 205 is also arranged to:

[0042] a) determining the actual instantaneous deceleration value of the vehicle during actuation of the braking device 202;

[0043] b) determining a real friction value between the braking device 202 and at least one wheel or at least one disc depending at least on the real instantaneous deceleration value, the test mass value of the vehicle and the actuation signal value;

[0044] c) Replacing the predetermined expected friction value stored in the storage medium 210, 210' with the determined actual friction value.

[0045] For example, in order to determine the actual instantaneous deceleration value of the vehicle, the control means 205 may comprise a speed sensor arrangement arranged to determine the actual forward speed of the vehicle (see Figure 5 :500, 500 ') or associated with the speed sensor device. The speed sensor device can be or include, for example, at least one rotation sensor, which is arranged to measure the rotation speed of the wheels or axles of the vehicle. Alternatively, the control device 205 can be arranged to receive the actual forward speed data from another control device outside the braking system.

[0046] Regarding the test mass value of the vehicle, the control device 205 may include or be associated with a weighing device arranged to determine the mass of the vehicle. For example, the weighing device may determine the mass of the vehicle via a deformation sensor device or by monitoring the vehicle suspension. Alternatively, the control device 205 may receive mass data from another control device external to the brake system. Alternatively, the test mass value may be manually input by a user, for example via a keyboard input.

[0047] Due to the fact that the predetermined stored expected friction value is replaced by the determined real friction value at the end of the calibration procedure, the control device 205 can take into account the determined real friction value instead of the predetermined friction value (which does not correspond to the actual friction conditions) when it is necessary to redetermine the value of the actuation signal 204 for the braking device 202.

[0048] Preferably, the control device 205 may further be arranged to determine the value of said actuation signal 204 according to at least one predetermined test condition. In this case, the control device 205 may further be arranged to verify that at least one predetermined test condition is met.

[0049] Furthermore, the control device 205 may be arranged to perform the above steps a), b) and c) when the control device 205 determines that at least one of the predetermined test conditions is met.

[0050] Preferably, at least one predetermined test condition may be a predetermined test forward speed. In this case, as already explained above and as for example in Figure 5 As can be observed in the figure, the control device 205 of the braking system 200 may comprise a speed sensor device 500 arranged to measure the actual forward speed or at least be associated with a speed sensor device 500' arranged to measure the actual forward speed. Otherwise, the control device 205 of the braking system may be arranged to receive the actual forward speed data from a further control device 502 external to the braking system. Furthermore, the control device 205 may be arranged to determine that the predetermined test condition is met when the predetermined forward speed and the actual forward speed substantially coincide.

[0051] Preferably, at least one predetermined test condition may be a predetermined test grip value between at least one wheel of the vehicle and the driving surface. In this case, the control device 205 of the braking system may include or be associated with a grip determination device arranged to measure the actual grip value. Alternatively, the control device 205 of the braking system may be arranged to receive the actual grip value between at least one wheel of the vehicle and the driving surface from a further control device external to the braking system. Furthermore, the control device may be arranged to determine that the predetermined test condition is met when the predetermined test grip value and the actual grip value substantially coincide.

[0052] Preferably, the control device 205 may also be arranged to:

[0053] - receiving a request for service braking;

[0054] - actuating the braking device 202 via an actuation signal having a value determined according to the determined real friction value and being suitable for applying a service braking force to the braking device 202 corresponding to the received service braking request.

[0055] In other words, after calibrating the determined real friction value, the control device 205 of the brake system 200 can take this calibrated real friction value into account for controlling the service braking to be performed by the brake system.

[0056] Alternatively or additionally, the control device 205 may also be arranged to:

[0057] - receiving an emergency braking request;

[0058] - actuating said braking device 202 via an actuation signal 204 having a value determined as a function of the determined real friction value and adapted to apply to said braking device an emergency braking force corresponding to the received emergency braking request.

[0059] In other words, after calibration of the determined real friction value, the control device 205 of the brake system 200 may manage the actuation of emergency braking to be performed by the brake system. Emergency braking may also be managed as a function of the calibrated real friction value.

[0060] As a non-limiting example, the control device 205 may be arranged to determine the actual friction value between the braking device and at least one wheel or at least one disc via the following formula:

[0061]

[0062] where μ reale is the actual friction value, m is the test mass value of the vehicle, a inst_reale is the actual instantaneous deceleration value, and A sig is the value of the actuation signal 204 .

[0063] Similarly, the control device 205 may be arranged to determine the value of the actuation signal 204 via the following formula:

[0064]

[0065] Among them A sig is the value of the actuation signal 204, m is the test mass value of the vehicle, a test is the expected instantaneous deceleration value, and μ pred is the predetermined expected friction value.

[0066] Preferably, the magnitude value of the braking force F converted by the braking device can depend on characteristic parameters specific to the braking device.

[0067] In this case, the control device 205 may also be arranged to:

[0068] - determining said value of said actuation signal as a function of said characteristic parameter of said braking device;

[0069] - The actual friction value between the braking device and at least one of the wheels or at least one of the discs is determined also as a function of the characterizing parameter specific to the braking device.

[0070] For example, the value assumed by the brake system characterization parameter may depend on one or more of the following characterization factors:

[0071] - The geometry of the brake;

[0072] -Diversity of braking devices;

[0073] - The efficiency of the braking system.

[0074] For example, the geometry of the brake device may include one or more of the following parameters:

[0075] - The braking radius of the brake device disc brake system, the spokes of the wheel to which the brake device will apply braking force, the surface of the brake piston of the brake cylinder of the brake device, the amplification ratio of the braking force generated by the lever of the brake device, etc.

[0076] For example, the diversity of the brake device may include the number of brake application devices of the brake device. Figure 3a and 3b As seen in FIG. 2 , the brake device 202 may include a plurality of brake applying elements 300. For example, the brake applying device 300 may include or be at least one of the following: a brake pad or a brake shoe, or the like (friction lining).

[0077] For example, the efficiency of a braking device may represent a value indicative of the ability of the braking device to apply a braking force in light of any force losses / dispersion due to mechanical structural characteristics of the braking device.

[0078] Preferably, the control device 205 may also be arranged to:

[0079] - also determining the value of the actuation signal 204 as a function of the initial activation value;

[0080] - Also depending on the initial activation value, a real friction value between the braking device 202 and at least one wheel or at least one axle or at least one disc is determined.

[0081] In particular, as in Figure 4 As seen in the figure, the value of the initial activation value can be such that when provided to the braking device 202, it allows / causes the braking device 202 to transition from a disassembled state C1 to a contact state C2, in which the braking device does not contact at least one wheel or axle or disc, and in which the braking device contacts at least one wheel or axle or disc.

[0082] Preferably, when both the characterizing parameter k and the initial activation value q are provided, the control device 205 may be arranged to determine the actual friction value between the braking device 202 and at least one of the wheels or at least one of the discs via the following formula:

[0083]

[0084] where μ reale is the actual friction value, m is the test mass value of the vehicle, a inst_reale is the real instantaneous deceleration value, k is the braking device characterization parameter, A sig is the actuation signal value, and q is the initial actuation value.

[0085] Obviously, the value of the characterization parameter k can be equal to 1, and the value of the initial activation value q can be equal to 0.

[0086] Similarly, the control device 205 may be arranged to determine the value of the actuation signal 204 via the following formula:

[0087]

[0088] Among them A sig is the value of the actuation signal 204, m is the test mass value of the vehicle, a test is the expected instantaneous deceleration value, k is the characterization parameter, μ pred is the predetermined expected friction value, and q is the initial actuation value.

[0089] Preferably, the brake device 202 may be pneumatic, and the determined actuation signal value may be a pneumatic pressure value.

[0090] Alternatively, the brake device 202 may be electro-pneumatic or electro-mechanical, and the value of the determined actuation signal may be an electrical value.

[0091] In a further aspect, the invention also relates to a system for calibrating a brake system of at least one vehicle, in particular at least one railway vehicle.

[0092] like Figure 6 As can be seen in FIG. 2 , the braking system 200 also includes a braking device, which is arranged to receive an actuation signal and to apply a corresponding braking force to at least one wheel of the vehicle or at least one disc associated with at least one wheel or axle of the vehicle. The intensity value of the braking force applied by the braking device 202 is a function of the value of the actuation signal 204.

[0093] The brake system 200 comprises a control device 205, which is arranged to:

[0094] - receiving a test brake request 206 indicating a desired instantaneous deceleration value;

[0095] - determining a value of said actuation signal 204, said value allowing said braking device 202 to apply to at least one of said wheels or at least one of said discs a braking force intensity value such that at least one of said vehicles will decelerate according to said expected instantaneous deceleration value;

[0096] Actuating the braking device 202 in dependence on the determined value of the actuation signal 204 .

[0097] The control device 205 is further arranged to determine a value of said actuation signal 204 as a function of at least a predetermined expected friction value between the braking device and at least one wheel or at least one disc, a test mass value of at least one vehicle and a value of said expected instantaneous deceleration.

[0098] The predetermined expected friction value between the brake device 202 and at least one wheel or at least one disc is arranged to be stored in a storage medium 210 comprised in the control device 205 of the brake system or in a storage medium 210 ′ associated with the brake system control device 205 .

[0099] like Figure 6 or Figure 7 As can be seen in FIG. 4 , the calibration system comprises a calibration control device 400 which is arranged in association with a brake system 200 of at least one vehicle and which receives a value of an actuation signal 204 determined by a control device of the brake system.

[0100] Preferably, the calibration control device 400 may be or include at least one of the following: a controller, a processor, a microprocessor, a microcontroller, at least one PLC, an FPGA, etc.

[0101] The calibration control device 400 is also arranged to:

[0102] a) determining, from said value of the actuation signal 204, a real instantaneous deceleration value of the vehicle during the actuation of the braking device 202;

[0103] b) determining a real friction value between the braking device and at least one wheel or at least one disc depending at least on the real instantaneous deceleration value, the test mass value of the vehicle 208 and the value of the actuation signal 204;

[0104] c) Replacing the predetermined expected friction value stored in the storage medium 210, 210' with the determined actual friction value.

[0105] For example, in order to determine the actual instantaneous deceleration value of the vehicle, the calibration control device 400 may include or be associated with a speed sensor device (not shown in the figure) arranged to determine the actual vehicle forward speed. The speed sensor device may be or include, for example, at least one rotation sensor arranged to measure the rotation speed of the wheels or axles of the vehicle. Alternatively, the calibration control device 400 may be arranged to receive the actual forward speed data directly from the control device 205 of the braking system or from another control device external to the calibration system and the braking system.

[0106] With regard to the vehicle test mass value, the calibration control 400 may include or be associated with a weighing device arranged to determine the mass of the vehicle. For example, the weighing device may determine the mass of the vehicle via a deformation sensor device or by monitoring the vehicle suspension. Alternatively, the calibration control 400 may receive mass data directly from the control device 205 of the braking system or from another control device external to the calibration system and the braking system. As a further alternative, the test mass value may be manually input by a user, for example via a keyboard input.

[0107] Preferably, the control device 205 of the brake system 200 may also be arranged to determine the value of the actuation signal 204 depending on at least one predetermined test condition.

[0108] In this case, the calibration control 400 of the calibration system may also be arranged to verify that at least one predetermined test condition is fulfilled.

[0109] Thus, the calibration control device 400 may be arranged to perform the above steps a), b) and c) when the calibration control device 400 determines that at least one predetermined test condition is met.

[0110] Preferably, at least one predetermined test condition may be a predetermined test forward speed. In this case, the calibration control device 400 of the calibration system may include a speed sensor device arranged to measure the actual forward speed or at least be associated with a speed sensor device (not shown in the figure) arranged to measure the actual forward speed. Alternatively, the calibration control device 400 of the calibration system may be arranged to receive actual forward speed data from an additional control device external to the calibration system or directly from the control device 205 of the braking system. Furthermore, the calibration control device 400 of the calibration system may be arranged to determine that the predetermined test condition is met when the predetermined test forward speed and the actual forward speed are substantially consistent.

[0111] Preferably, at least one predetermined test condition may be a predetermined test grip value between at least one wheel of the vehicle and the driving surface. In this case, the calibration control device 400 of the calibration system may include or be associated with a grip determination device arranged to measure the actual grip value. Alternatively, the calibration control device 400 of the calibration system may be arranged to receive the actual grip value between at least one wheel of the vehicle and the driving surface via a further control device external to the calibration system or directly from the control device 205 of the braking system. Furthermore, the calibration control device of the calibration system may be arranged to determine that the predetermined test condition is met when the predetermined test grip value and the actual grip value are substantially consistent.

[0112] The preferred embodiments described above with respect to the brake system 200 may find similar application with respect to the calibration system.

[0113] As a non-limiting example, the calibration control device 400 may be arranged to determine the real friction value between the braking device and at least one wheel, one axle or one disc via the following formula:

[0114]

[0115] where μ reale is the actual friction value, m is the test mass value of the vehicle, a inst_reale is the actual instantaneous deceleration value, and A sig is the actuation signal value.

[0116] Preferably, the intensity value of the braking force F converted by the braking device can depend on a characterizing parameter specific to said braking device. The description of the characterizing parameter provided above and not repeated here can also be applied analogously in this context.

[0117] Preferably, the calibration control device 400 may also be arranged to determine the real friction value between the braking device and at least one of the wheels or at least one of the discs also depending on the initial activation value, wherein the value of the initial activation value may be such that when provided to the braking device, it allows / causes the braking device to transition from a dismounted condition C1, in which the braking device does not contact at least one wheel or at least one axle or at least one disc, to a contact condition C2, in which the braking device contacts at least one wheel or at least one axle or at least one disc.

[0118] Preferably, when both the characterizing parameter k and the initial actuation value q are present, the calibration control device 400 may be arranged to determine the real friction value between the braking device 202 and at least one of the wheels or at least one of the axles or at least one of the discs via the following formula:

[0119]

[0120] where μ reale is the actual friction value, m is the test mass value of the vehicle, a inst_reale is the actual instantaneous deceleration value, A sig is the actuation signal value, k is the characterization parameter, and q is the initial actuation value.

[0121] For example, the calibration control device 400 of the calibration system may be arranged to cooperate with the control device 205 of the braking system. For example, the calibration system may be installed directly in the vehicle (e.g. Figure 7 ), or the calibration system can be external to the vehicle and connected to the brake system during calibration and can be disconnected from the brake system at the end of calibration (as shown in Figure 6 ).

[0122] In a further aspect, the invention relates to a method for calibrating a braking system 200 of at least one vehicle, in particular at least one railway vehicle, which is implemented / actuated via a control device.

[0123] For example, the control device may be or include the control device 205 of the braking system and / or the calibration control device 400 of the calibration system.

[0124] Likewise, the braking system 200 comprises a braking device 202 arranged to receive an actuation signal 204 and to apply a corresponding braking force F to at least one wheel or axle of the vehicle or to at least one disc associated with at least one wheel or axle of the vehicle. The value of the intensity of the braking force applied by the braking device 202 is a function of the value of the actuation signal 204.

[0125] The calibration method consists of the following steps:

[0126] - receiving a test brake request 206 indicating a desired instantaneous deceleration value;

[0127] - determining a value of the actuation signal 204 as a function of at least a predetermined expected friction value between the braking device 202 and at least one wheel or at least one disc stored in the storage medium 210, 210', a test mass value of at least one vehicle and a value of said expected instantaneous deceleration, said value allowing said braking device to apply a braking force intensity value to at least one of said wheels or at least one axle or at least one of said discs, such that at least one of said vehicles will be decelerated according to said expected instantaneous deceleration value;

[0128] Actuating the braking device 202 as a function of the determined value of the actuation signal 204 .

[0129] The calibration method also includes the following steps:

[0130] a) determining the actual instantaneous deceleration value of the vehicle during the actuation of the braking device 202 according to the value of the actuation signal;

[0131] b) determining a real friction value between said braking device and at least one of said wheels or at least one of said discs as a function of at least said real instantaneous deceleration value, a test mass value of said vehicle and said actuation signal value;

[0132] c) Replacing the predetermined expected friction value stored in the storage medium 210, 210' with the determined actual friction value.

[0133] Preferably, the step of determining the value of the actuation signal can also be performed according to at least one predetermined test condition. In this case, the calibration method can also comprise the following steps:

[0134] - verifying that at least one of said predetermined test conditions is satisfied;

[0135] Steps a), b) and c) are performed when the verification indicates that at least one of the predetermined test conditions is met.

[0136] As explained above, the predetermined test condition may involve verifying a predetermined test forward speed or a predetermined test grip value between at least one vehicle wheel and the driving surface.

[0137] The preferred embodiments described above for the brake system and the calibration system may find similar application for the calibration method.

[0138] For example, step b) may comprise determining the actual friction value between the braking device and at least one wheel or at least one axle or at least one disc via the following formula:

[0139]

[0140] where μ reale is the actual friction value, m is the test mass value of the vehicle, a inst_reale is the actual instantaneous deceleration value, and A sig is the actuation signal value.

[0141] In a further example, step b) may comprise determining the actual friction value between the braking device and at least one wheel or at least one axle or at least one disc via the following formula:

[0142]

[0143] where μ reale is the actual friction value, m is the test mass value of the vehicle, a inst_reale is the actual instantaneous deceleration value, A sig is the actuation signal value, k is the characterization parameter, and q is the initial actuation value.

[0144] The explanations provided above for the characterization parameters and initial actuation values ​​are similar in application and are not repeated here.

[0145] In addition, the present invention also relates to a vehicle, in particular a railway vehicle. In particular, the vehicle may be, for example, a railway vehicle and comprises a brake system according to any one of the above-mentioned embodiments.

[0146] In a further embodiment, the vehicle comprises a braking system according to any of the above embodiments and a system for calibrating a braking system of at least one vehicle.

[0147] Preferably, the present invention can be particularly applicable in the field of rail vehicles / convoys travelling on railway tracks. A convoy can be understood as a plurality of vehicles interconnected to each other. A convoy can be a train.

[0148] For example, the vehicle referred to herein may be a locomotive or a carriage, and the route / road segment may include a track (a driving surface) on which the wheels of the locomotive roll. However, the embodiments described herein should not be construed as being limited to rail vehicles. For example, the vehicle may be a car, a truck (e.g., a highway semi-trailer, a mining truck, a logging truck, etc.), and the route may be a highway or a trail.

[0149] Preferably, the advantage achieved is that an automatic solution for a vehicle braking system has been provided, which allows reducing the time needed to tune the braking parameters of the braking system with respect to the friction value between the braking device and the wheel or a disc associated with the wheel.

[0150] A further advantage is obtained in that a solution has been provided for reducing the time taken to tune the braking parameters of the braking system with respect to the friction value between the braking device and the wheel or a disc associated with the wheel.

[0151] Another advantage is that a solution has been provided allowing recalibration of a predetermined expected friction value between the braking device and at least one wheel or at least one disc during the service life of the vehicle without having to take the vehicle out of service for the intervention of a qualified operator.

[0152] According to the present invention, various aspects and embodiments of a brake system, a system for calibrating a brake system of at least one vehicle, and a method for calibrating a brake system of at least one vehicle have been described. It is contemplated that each embodiment may be combined with any other embodiment. Furthermore, the present invention is not limited to the described embodiments, but may be varied within the scope defined by the appended claims.

Claims

1. A braking system (200) for at least one vehicle (V), in particular at least one railway vehicle, wherein the braking system comprises a braking device (202) arranged to receive an actuation signal (204) and to apply a corresponding braking force (F) to at least one wheel of the vehicle or to at least one disc associated with at least one wheel or axle of the vehicle; wherein the magnitude of the braking force (F) applied by the braking device (202) is a function of the value of the actuation signal (204); The braking system (200) further comprises a control device (205), which is arranged to: receiving a test brake request indicating an expected instantaneous deceleration value (206); determining said value of said actuation signal (204) which allows said brake device (202) to apply to at least one of said wheels or at least one of said discs a braking force (F) having an intensity value such that at least one of said vehicles will decelerate according to said expected instantaneous deceleration value; actuating the braking device (202) according to the determined value of the actuation signal (204); wherein said control device (205) is arranged to determine said value of said actuation signal (204) as a function of at least a predetermined expected friction value between said braking device (202) and at least one of said wheels or at least one of said discs, a test mass value (208) of at least one vehicle and said value of said expected instantaneous deceleration; wherein said predetermined expected friction value between said braking device and at least one of said wheels or at least one of said discs is arranged to be stored in a storage medium (210) comprised in said control device (205) or in a storage medium (210') associated with said control device; The control device (205) is also arranged to: a) determining a true instantaneous deceleration value of the vehicle during actuation of the braking device (202); b) determining a real friction value between said braking device and at least one of said wheels or at least one of said discs as a function of at least said real instantaneous deceleration value, said test mass value of said vehicle and said actuation signal value; c) replacing the predetermined expected friction value stored in the storage medium (210, 210') with the determined actual friction value.

2. A braking system according to claim 1, wherein the control device (205) is arranged to determine the value of the actuation signal (204) also in dependence on at least one predetermined test condition; The control device (205) is also arranged to: verifying that at least one predetermined test condition is satisfied; The control device (205) is arranged to perform the steps a), b) and c) when the control device (205) determines that at least one of the predetermined test conditions is met.

3. The braking system according to claim 1 or 2, wherein the control device (205) is further arranged to: receiving a service brake request; actuating the brake device (202) via an actuation signal (204), the actuation signal having a value determined according to the determined real friction value and being suitable for applying a service braking force corresponding to the received service braking request to the brake device; and / or receiving an emergency braking request; The brake device (202) is actuated via an actuation signal (204), the actuation signal having a value determined according to the determined real friction value and being suitable for applying an emergency braking force corresponding to the received emergency braking request to the brake device.

4. Braking system according to any of the preceding claims, wherein the intensity value of the braking force (F) converted by the braking device depends on a characterizing parameter specific to the braking device; The control device (205) is further arranged to: determining the value of the actuation signal according to the characteristic parameter of the brake device; The actual friction value between the braking device and at least one of the wheels or at least one of the disks is also determined as a function of the characterizing parameter specific to the braking device.

5. The braking system according to claim 4, wherein the value of the characteristic parameter of the braking device is a function of at least one of: The geometry of the braking device; The diversity of the braking device; The efficiency of the braking device.

6. The braking system according to any one of the preceding claims, wherein the control device (205) is further arranged to: further determining the value of the actuation signal (204) based on an initial activation value; determining said real friction value between said braking device and at least one of said wheels or at least one of said discs further depending on said initial activation value; The value of the initial activation value is such that when provided to the braking device, it allows the braking device to transition from a dismounted condition (C1) to a contact condition (C2), in which the braking device does not contact at least one wheel or disc, and in which the braking device contacts at least one wheel or disc.

7. The braking system according to at least claims 4 and 6, wherein the control device (205) is arranged to determine the real friction value between the braking device (202) and at least one of the wheels or at least one of the discs via the following formula: where μ reale is the actual friction value, m is the test mass value of the vehicle, a inst_reale is the actual instantaneous deceleration value, A sig is the actuation signal value, k is the brake device characterizing parameter, and q is the initial actuation value.

8. The braking system according to any of the preceding claims, wherein the braking device (202) is pneumatic and the determined actuation signal value (204) is a pneumatic pressure value.

9. The brake system according to any one of claims 1 to 7, wherein the brake device (202) is electropneumatic or electromechanical, and the determined actuation signal value is an electrical signal.

10. A braking system according to any one of the preceding claims 2 to 9, wherein at least one predetermined test condition is a predetermined test forward speed; wherein the brake system control device (205) comprises a speed sensor device (500) arranged to measure an actual forward speed or is at least associated with a speed sensor device (500') arranged to measure an actual forward speed; or wherein the brake system control device (205) is arranged to receive actual forward speed data from a further control device (502) external to the brake system; The control means (205) is arranged to determine that the predetermined test condition is satisfied when the predetermined test forward speed and the actual forward speed are substantially consistent.

11. A braking system according to any one of claims 2 to 10, wherein at least one predetermined test condition is a predetermined test grip value between at least one wheel of the vehicle and the driving surface; wherein the brake system control device comprises or is associated with a grip force determination device arranged to measure an actual grip force value; or wherein the brake system control device is arranged to receive an actual grip value between at least one wheel of the vehicle and a driving surface from a further control device external to the brake system; The control means is arranged to determine that the predetermined test condition is met when the predetermined test grip value and the actual grip value substantially agree.

12. A system for calibrating a braking system of at least one vehicle, in particular at least one railway vehicle, wherein the braking system (200) comprises a braking device (202) arranged to receive an actuation signal (204) and to apply a corresponding braking force (F) to at least one wheel of the vehicle or to at least one disc associated with at least one wheel or axle of the vehicle; wherein the magnitude of the braking force (F) applied by the braking device (202) is a function of the value of the actuation signal (204); The braking system further comprises a control device (205) arranged to: receiving a test brake request indicating an expected instantaneous deceleration value (206); determining said value of said actuation signal (204) which allows said brake device (202) to apply a braking force (F) intensity value to at least one of said wheels or at least one of said discs such that at least one of said vehicles will decelerate according to said expected instantaneous deceleration value; actuating the braking device (202) according to the determined value of the actuation signal (204); wherein said control means (205) is arranged to determine said value of said actuation signal (204) as a function of at least a predetermined expected friction value between said brake means (202), a test mass value of at least one vehicle (208) and said value of said expected instantaneous deceleration; wherein the predetermined expected friction value between the braking device (202) and at least one of the wheels or at least one of the discs is arranged to be stored in a storage medium (210) included in a control device (205) of the braking system or in a storage medium (210') associated with the control device (205) of the braking system; The system for calibrating a brake system comprises a calibration control device (400) arranged to be associated with the brake system (200) of at least one vehicle (V) and arranged to: receiving said value of said actuation signal (204) determined by said brake system control device (205); The calibration control device (400) is also arranged to: a) determining a true instantaneous vehicle deceleration value during actuation of said braking device (200) from said value of said actuation signal (204); b) determining a real friction value between the braking device (202) and at least one of the wheels or at least one of the discs based on at least the real instantaneous deceleration value, the test mass value of the vehicle and the actuation signal value; c) replacing the predetermined expected friction value stored in the storage medium (210, 210') with the determined actual friction value.

13. A system for calibrating a brake system according to claim 12, wherein the brake system control device (205) is arranged to determine the actuation signal value also in dependence on at least one predetermined test condition; The calibration control device (400) of the calibration system of the brake system is further arranged to: verifying that at least one predetermined test condition is satisfied; The calibration control device (400) is further arranged to perform steps a), b) and c) when the calibration control device (400) determines that at least one of the predetermined test conditions is satisfied.

14. A method for calibrating a braking system (200) of at least one vehicle (V), in particular at least one railway vehicle, performed via a control device (205, 400), wherein the braking system (200) comprises a braking device (202) arranged to receive an actuation signal (204) and to apply a corresponding braking force (F) to at least one wheel of the vehicle or to at least one disc associated with at least one wheel or axle of the vehicle; wherein the magnitude of the braking force (F) applied by the braking device (202) is a function of the value of the actuation signal (204); The method comprises the following steps: receiving a test brake request indicating an expected instantaneous deceleration value (206); determining said value of said actuation signal (204) as a function of at least one predetermined expected friction value stored in a storage medium (210, 210') between said braking device (202) and at least one of said wheels or at least one of said discs, a test mass value of at least one vehicle and said value of said expected instantaneous deceleration, said value allowing said braking device to apply to at least one of said wheels or at least one of said discs an intensity value of said braking force (F) such that at least one of said vehicles will decelerate according to said expected instantaneous deceleration value; actuating the braking device (202) according to the determined actuation signal value; The procedure also includes the following steps: a) determining, from the value of the actuation signal, a real instantaneous deceleration value of the vehicle during actuation of the braking device (202); b) determining a real friction value between the braking device (202) and at least one of the wheels or at least one of the discs based on at least the real instantaneous deceleration value, the test mass value of the vehicle and the actuation signal value; c) replacing the predetermined expected friction value stored in the storage medium (210, 210') with the determined actual friction value.

15. The method of claim 14, wherein said step of determining said value of said actuation signal (204) is further performed according to at least one predetermined test condition; The method further comprises the following steps: verifying that at least one of the predetermined test conditions is satisfied; Steps a), b) and c) are performed when the verification indicates that at least one of the predetermined test conditions is met.

16. A vehicle, in particular a railway vehicle, comprising a brake system according to any one of claims 1 to 11.

17. A vehicle, in particular a railway vehicle, comprising: Braking system; A system for calibrating the braking system of at least one vehicle according to any one of claims 12 or 13.

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