ELECTRONIC DEVICE FOR REGULATING THE PRESSURE PROVIDED AT A RAIL BRAKE CALIPER

Description

[0001] The present invention relates to an electronic device for regulating the pressure supplied to a pneumatic cylinder brake caliper of railway rolling stock, via a pair of solenoid valves comprising an upper solenoid valve for increasing pressure and a lower solenoid valve for releasing pressure.

[0002] Railway rolling stock refers to a set of railway vehicles designed to move on a railway track. A railway vehicle can be a motorized or non-motorized carriage, a locomotive, a combination of locomotives and carriages, or a set of carriages with the motors distributed along their length. A railway vehicle is designed to run on rails and typically has wheels in contact with those rails.

[0003] The invention also relates to a system for regulating the pressure supplied to a pneumatic cylinder brake caliper of railway rolling stock, via a pair of solenoid valves comprising an upper solenoid valve for increasing pressure and a lower solenoid valve for releasing pressure, the system comprising the aforementioned electronic device.

[0004] The invention also relates to railway rolling stock comprising said regulation system.

[0005] Most railway rolling stock, with the exception of some light rail vehicles, uses a railway braking system where pneumatic energy is used to actuate the brake.

[0006] Typically, such a braking system is mainly composed of two elements, namely on the one hand a brake control, which generates a pressure proportional to the desired braking effort, and on the other hand a brake caliper with a pneumatic cylinder, which uses this pressure to press the pads onto the brake disc or the tread onto the wheel.

[0007] Over the past few decades, pneumatic control has aimed to be miniaturized and gradually an electric control for non-safety functions has been introduced, such as the service brake function, while the emergency brake control, which is a safety control, still currently remains primarily pneumatic.

[0008] By direct electropneumatic railway braking system, as developed over the last few decades, we mean an electrically controlled braking system where the service braking command (i.e. in nominal operating mode), or even the emergency braking command (i.e. in emergency operating mode) are electrical commands sent by an on-board computer network and / or by electrical lines following an action on a manual control dedicated to activating service or emergency braking by the railway vehicle driver, or by an automatic piloting system.

[0009] By "service braking" we mean the braking implemented within the railway vehicle to, in nominal operational mode, regulate its speed throughout its journey (i.e. brake more or less strongly), as well as to stop in station.

[0010] "Emergency braking" refers to braking implemented to stop the railway vehicle in the event of a situation that is potentially dangerous for the railway vehicle, with a specified level of performance and safety.

[0011] The state of the art includes, in particular, documents EP-A1-3 851 357, US-A-5 735 579 and EP-A2-4 035 959.

[0012] Miniaturized pneumatic brake controls, known as "compact" brakes, are currently generally proprietary solutions, not reconfigurable without complex proprietary development that is sometimes incompatible for different railway rolling stock, and remain unsatisfactory in terms of compactness.

[0013] Thus, the invention aims in particular to break free from existing solutions while further compacting the brake control in order to reduce its cost and weight.

[0014] To this end, the invention relates to an electronic device for regulating the pressure supplied to a pneumatic cylinder brake caliper of railway rolling stock, via a pair of solenoid valves comprising an upper solenoid valve for pressure increase and a lower solenoid valve for pressure release, said electronic device comprising an electronic pressure regulator configured to: control said pair of solenoid valves via at least one electronic control by continuously comparing a first electrical signal representative of the pressure measured within said caliper to a second electrical signal representative of a reference pressure, and control the opening of: the upper intake solenoid valve when the value of the first electrical signal is less than that of the second electrical signal, or the lower exhaust solenoid valve when the value of the first electrical signal is greater than that of the second electrical signal; in the presence of an emergency braking request, said second electrical signal representing a reference pressure corresponding to an electrical signal representing the pressure value required for emergency braking of said railway rolling stock, in the absence of an emergency braking request, said second electrical signal representing a reference pressure corresponding to an electrical signal obtained from at least one service braking input of said device provided(s) by at least one external electronic control unit of said electronic device and / or provided(s) by a train control and monitoring system.

[0015] The architecture of the electronic device proposed according to the present invention makes it possible to replace most of the pneumatic components of the brake control system with substitute electronic components, including for the safety function of emergency braking control. Indeed, the present invention takes advantage of the strong similarity between electricity and pneumatics by considering voltage to be equivalent to pressure, and electric current to be equivalent to airflow, so that according to the present invention, every pneumatic component has an electrical equivalent.

[0016] More specifically, the present invention consists of replacing the usual pneumatic elements with equivalent electrical or digital elements implemented within said device according to the present invention, to advantageously control a single pair of pneumatic solenoid valves, one to increase the pressure in the brake cylinder, the other to decrease it.

[0017] According to other advantageous aspects of the invention, the electronic device for regulating the pressure supplied to a pneumatic cylinder brake caliper of railway rolling stock, via a pair of solenoid valves comprising an upper pressure-increasing solenoid valve and a lower pressure-relieving solenoid valve, comprises the following features: According to one advantageous aspect, the electronic device further comprises: a first acquisition module configured to: receive said first electrical signal representative of said measured pressure, said first electrical signal being provided by a first external pressure transducer of said electronic device, said first pressure transducer being capable of transforming the measured pressure, within said caliper, into said first electrical signal, and providing said first electrical signal as input to said electronic regulator, a reconfigurable memory space configured to: store said electrical signal representative of the pressure value required for emergency braking of said railway rolling stock, provide said electrical signal representative of the pressure value required for emergency braking as input to said electronic regulator,In the presence of an emergency braking request, at least one second acquisition module is configured to: receive and / or generate said electrical signal obtained from at least one service braking input of said device provided(s) by at least one external electronic control unit of said electronic device and / or provided(s) by a train control and monitoring system, and provide said electrical signal obtained as an input to said electronic regulator, in the absence of an emergency braking request.

[0018] In addition to one advantageous aspect, the system also includes: a third acquisition module configured to: receive a third electrical signal representative of the pressure measured within a suspension associated with said brake caliper, said third electrical signal being provided by a second external pressure transducer to said electronic device, said second pressure transducer being capable of transforming the pressure measured within said suspension into said third electrical signal, and providing said third electrical signal as input to at least one load compensation module, at least one load compensation module configured to determine the pressure value required for emergency braking, or required for immobilizing braking of said railway rolling stock as a function of the load of said railway rolling stock of which the third electrical signal is representative.

[0019] According to an advantageous aspect, said first pressure transducer and / or said second pressure transducer are directly integrated into said electronic device using a pneumatic tube connected directly between said device and respectively said caliper and / or said suspension.

[0020] Accordingly, one advantageous aspect of the device is that it also includes a forced regulation module, configured to acquire at least two distinct types of commands from: force the intake solenoid valve to the closed state, or force the exhaust solenoid valve to the open state. said at least two orders being issued by an external electronic brake control unit to said electronic device, said electronic brake control unit being capable of detecting wheel slippage of said rolling stock, and of controlling said sliding by means of said forcing orders of the solenoid valves, said forced regulation module being further configured to transform said acquired order into a forced regulation command which takes priority over the electronic command supplied at the output by the electronic pressure regulator and destined for said pair of solenoid valves.

[0021] As an advantageous feature, the device also includes a hysteresis module configured to: compare the value of the first electrical signal to a predetermined threshold representing a limit before overpressure within said caliper, and in case of exceeding said threshold, generate a pressure release order, which takes priority over the forced regulation command, and is sent to said pair of solenoid valves.

[0022] In addition to its advantages, the device also includes a fourth acquisition module configured to: receive a signal representative of the absence of pressure in an indirect cylinder when the brake caliper is a parking brake caliper comprising two brake cylinders: a direct cylinder dedicated to braking outside parking and an indirect cylinder dedicated to parking braking of railway rolling stock; generate a pressure release order, which has priority over the forced regulation command, and is intended for said pair of solenoid valves.

[0023] According to an advantageous aspect, the electronic command issued by default to said pair of solenoid valves is a pressure admission command, when the brake caliper includes a direct cylinder dedicated to service braking and emergency braking, or a pressure release command, when the brake caliper is a parking brake caliper comprising only an indirect cylinder dedicated to both service braking, emergency braking and / or the parking brake.

[0024] According to an advantageous aspect, the device further includes a timer module configured to establish a minimum transition time between two distinct states of the pair of solenoid valves, said two distinct states being associated with the application of two separate electronic commands.

[0025] According to an advantageous aspect, the device further includes a self-test module configured to automatically launch a self-test of said device, and / or a self-test of the pair of solenoid valves, and / or of said brake caliper.

[0026] According to an advantageous aspect, the device further includes a fault monitoring module configured to at least monitor the device's own internal power supply.

[0027] Accordingly, one advantageous aspect of the device also includes an accelerometer configured to measure the longitudinal acceleration of said railway rolling stock, a combination module configured to combine said longitudinal acceleration with a speed of said railway rolling stock provided by an external electronic brake control unit and generate a consolidated speed suitable for use at least by said load compensation module.

[0028] The invention also relates to a system for regulating the pressure supplied to a pneumatic cylinder brake caliper of railway rolling stock, via a pair of solenoid valves comprising an upper solenoid valve for pressure increase and a lower solenoid valve for pressure release, the system comprising at least: an electronic device as described above; said pair of solenoid valves.

[0029] According to an advantageous aspect, the system further includes a relay valve having a 1:1 regulation ratio, said relay valve being located between the pair of solenoid valves and the pneumatic cylinder brake caliper, the pair of solenoid valves being configured to generate a pilot pressure for said relay valve itself configured to then amplify the output flow, according to a predetermined amplification, for the pneumatic cylinder brake caliper.

[0030] The invention also relates to railway rolling stock comprising the aforementioned regulation system.

[0031] These features and advantages of the invention will become clearer upon reading the following description, given solely by way of non-limiting example, and made with reference to the accompanying drawings, in which: [ Fig 1 ] there figure 1 is a schematic representation of an electronic device for regulating the pressure supplied to a pneumatic cylinder brake caliper of railway rolling stock according to a simplified embodiment of the present invention, [ Fig 2 ] there figure 2 is a schematic representation of an electronic pressure regulation device according to different variants of the present invention.

[0032] There figure 1 is a schematic representation of a system for regulating the pressure supplied to a pneumatic cylinder brake caliper E of railway rolling stock, via a pair of solenoid valves (i.e. solenoid valves) comprising an upper inlet solenoid valve EV 1 for increasing pressure and an exhaust solenoid valve, lower, EV 2 for releasing pressure according to a simplified embodiment.

[0033] More specifically, according to the present invention such a pressure regulation system includes an electronic device 10 for regulating the pressure supplied to the pneumatic cylinder brake caliper E, said electronic device 10 including an electronic pressure regulator 12.

[0034] Such an electronic pressure regulator 12 is configured to control said pair of solenoid valves EV 1 and EV 2 via at least one electronic control by continuously comparing a first electrical signal PE, representative of said pressure within said yoke E, to a second electrical signal, representative of a reference pressure. It should be noted that the first electrical signal PE, representative of said pressure within said yoke E, is obtained by direct measurement at the output of the pressure regulation system 12 after the pair of solenoid valves EV 1 and EV 2, as shown in the diagram. figure 1 (all connected by piping).

[0035] Furthermore, the electronic pressure regulator 12 is configured to control, via command C 1, the opening of the upper solenoid valve EV 1 when the value of the first electrical signal is less than that of the second electrical signal, or, via command C 2, the lower solenoid valve EV 2 when the value of the first electrical signal is greater than that of the second electrical signal. This is based on the understanding that, in the presence of an emergency braking FU request, the second electrical signal represents a reference pressure corresponding to an electrical signal representing the pressure value required for the emergency braking of the railway rolling stock, and that, in the absence of an emergency braking FU request, the second electrical signal represents a reference pressure corresponding to an electrical signal (i.e.analog or digital) RFs obtained from at least one service braking input of said device 10 supplied by at least one external electronic control unit of said electronic device 10 and / or supplied by a TCMS train control and monitoring system (from English . Train Control and Monitoring System).

[0036] According to an architectural example illustrated by the figure 1 The electronic control device 10 also includes a first electronic acquisition module 14. The first electronic acquisition module 14 is configured to receive said first electrical signal representative of said measured pressure, said first electrical signal being provided by a pressure transducer T P1 external to said electronic device 10, said first pressure transducer T P1 being suitable for transforming the measured pressure, within said yoke E, into said first electrical signal PE, and for providing said first electrical signal PE as input to said electronic regulator 12.

[0037] The electronic device 10 further includes a reconfigurable memory space PD. Such a reconfigurable memory space PD is configured to store said electrical signal representing the pressure value required for emergency braking of said railway rolling stock, and configured to provide said electrical signal representing the pressure value required for emergency braking as input to said electronic controller 12, in the presence of an emergency braking FU request.

[0038] According to the simplified implementation of the figure 1 , the electronic device 10 further includes at least one second acquisition module 16 configured to receive said electrical signal from an input 15 supplied by external control electronics to said electronic device 10 or supplied by a train control and monitoring system, and to supply said electrical signal as input to said electronic regulator 12, in the absence of an emergency braking request.

[0039] In other words, the electronic pressure regulator 12 controls the two solenoid valves EV1 and EV2. If the pressure in the brake caliper cylinder is too low, the electronic pressure regulator 12 transmits an electrical command C4, for example, a bit with a value of zero (or conversely, a value of one), to the upper solenoid valve EV1, in order to admit air from a pressure source (typically a brake reservoir RF followed by a pressure reducer RP as illustrated by the figure 1 ).

[0040] Conversely, when the pressure is too high in the brake caliper cylinder, the electronic pressure regulator 12 transmits a command C 2 for example a bit with a value of one (or conversely with a value of zero) to the upper solenoid valve EV 2, in order to release the pressure into the atmosphere A.

[0041] To do this, the electronic pressure regulator 12 continuously compares the reference pressure with the actual pressure of the brake caliper cylinder, the actual pressure being measured via the external pressure transducer T P1 of the electronic device 10. The external pressure transducer T P1 is designed to provide the first electrical signal PE representative of the said pressure measured within the said caliper E to the first electronic acquisition module 14 of the regulation device 10.

[0042] By default, the reference pressure stored in the reconfigurable memory space PD is that required for emergency braking to ensure system safety. If emergency braking is not required, then the reference pressure corresponds to an RF electrical signal obtained from at least one service braking input, via said second acquisition module 16 of said device 10, provided by at least one external electronic control unit of said electronic device 10 and / or provided by a TCMS (Train Control and Monitoring System). Train Control and Monitoring Systems).

[0043] In other words, the emergency braking request acts as a switch to enforce the reference pressure stored within the reconfigurable PD memory space when emergency braking is required.

[0044] It should be noted that the architecture of device 10 according to the present invention is innovative insofar as all the functions implemented within device 10 via elements 12, 14, 16, and PD are implemented electronically and not by means of a pneumatic circuit as conventionally used, including for emergency braking management, and advantageously using a single pair of solenoid valves. Thus, the present invention reduces the number of pneumatic components, the cost, the mass, and the volume required for pressure regulation, while also allowing for better integration.

[0045] According to an alternative embodiment, not shown, the electronic pressure regulation device 10 is and / or includes a secure electronic card and includes an information processing unit formed for example of a memory including in particular the reconfigurable memory space PD, and a processor associated with the memory.

[0046] According to this embodiment, the electronic pressure regulator 12, the first acquisition module 14, and the second acquisition module 16 are each implemented as a programmable logic component, such as an FPGA (from the English Field Programmable Gate Array ) an FPGA not being considered as software but as hardware, or in the form of an integrated circuit, such as an ASIC (from the English Application Specific Integrated Circuit).

[0047] According to another embodiment, to achieve the required level of safety in emergency braking, a duplication of critical functions is necessary and for example implemented using a processor (integrating software, the electronic pressure regulator 12, the first acquisition module 14, the second acquisition module 16, each then being implemented in the form of software) redundanted by an FPGA as described above.

[0048] Advantageously, by its fully electronic nature, the electronic pressure regulation device 10 is factory configurable, in particular to reconfigure it (i.e. adapt it) to each specific application of the rolling stock in which it is intended to be installed.

[0049] It should be noted that according to a first variant of the simplified implementation of the figure 1 The two solenoid valves for air intake and exhaust (i.e., release) are implemented as a single component with two electrical inputs: one for intake control (C1) and one for exhaust control (C2). This variant thus presents a more compact pair of solenoid valves, allowing for better integration.

[0050] According to a second optional variant of the simplified embodiment of the figure 1 The pressure regulation system supplied to a caliper E further includes a relay valve having, for example, a 1:1 regulation ratio (i.e., a 1:1 ratio indicating that the output pressure is equal to the pilot pressure received at the inlet from the pair of solenoid valves EV1 and EV2, while providing a higher output flow rate than that received at the inlet, the output flow rate being limited only by the characteristics of the downstream circuit; alternatively, the output pressure is not necessarily equal to, but proportional to, the pilot pressure received at the inlet). This relay valve is located between the pair of solenoid valves EV1 and EV2 and the pneumatic cylinder brake caliper E, the pair of solenoid valves EV1 and EV2 being configured to generate a pilot pressure for said relay valve, which is itself configured to then amplify the output flow rate (i.e.via the generation of a higher airflow) according to a predetermined amplification to the pneumatic cylinder brake caliper E. In other words, the relay valve is itself configured to fill the pneumatic cylinder of caliper E to a pressure equal to the pilot pressure, and with a higher flow rate than that supplied at the inlet by the pair of solenoid valves EV 1 and EV 2. The relay valve is therefore a pressure source that imposes pressure on the circuit and thus reduces the airflow to the upstream pair of solenoid valves EV 1 and EV 2. The size, cost, and power consumption of the solenoid valves EV 1 and EV 2 are advantageously reduced.

[0051] There figure 2 is a schematic representation of an electronic pressure regulation device according to different variants of the present invention, the different variants being represented cumulatively on the embodiment of the figure 2 As an alternative, each variant described below can be added independently and optionally to the simplified embodiment of the figure 1 described previously.

[0052] According to a first optional variant, the electronic control device 10 further includes a third acquisition module 18 configured to receive a third electrical signal PS representative of the pressure measured within a suspension S associated with said brake caliper E, said third electrical signal being provided by a second external pressure transducer TP2 of said electronic device 10. Said second pressure transducer TP2 is suitable for transforming the pressure measured, within said suspension S, into said third electrical signal, and providing this third electrical signal as input to at least one load compensation module 20.

[0053] Furthermore, according to this first variant described in relation to the figure 2 , the electronic control device 10 further includes said at least one load compensation module 20 configured to determine the pressure value required for emergency braking of said railway rolling stock as a function of the load of said railway rolling stock of which the third electrical signal is representative.

[0054] In other words, according to this first variant, the default pressure reference used in case of emergency braking is compensated by the load (i.e., the pressure reference is a linear function of the load, the parameters of the linear function also being stored in memory and configurable according to the application), and not constant and stored in a memory space as illustrated in the figure 1 In practice, the pressure inside the suspension bellows S, this pressure being a reflection of the load on the railway rolling stock (i.e., train), is measured with the pressure transducer T P2. The output signal of the pressure transducer T P2 is then acquired by the third acquisition module 18 of the secure electronic board of the control device 10 and used as input for a load compensation function implemented by the load compensation module 20, which defines the pressure reference in the event of emergency braking.

[0055] It should nevertheless be noted that aberrant pressure measurements in the suspension S (too high or too low, for example because the pressure transducer T P2 is faulty or because the suspension cushion is punctured) are ignored (i.e. the linear function is then clipped).

[0056] Such load compensation in emergency braking makes it advantageous to always obtain the same deceleration, and therefore the same braking distance, regardless of the load of the railway rolling stock (i.e. train), as required in particular in certain markets.

[0057] According to a second optional variant, which can be combined with the previous variant or only combined with the simplified implementation of the figure 1 The electronic control device 10 further includes a forced control module 22, configured to acquire at least two distinct types of commands I1 and I2, enabling: to force the inlet solenoid valve EV 1 to the closed state I 1, and / or to force the exhaust solenoid valve EV 2 to the open state I 2, said at least two commands being issued by an external electronic brake control unit 24 to said electronic device 10, said electronic brake control unit 24 being capable of detecting wheel slippage of said railway rolling stock, and of controlling said slippage by means of said forcing commands of solenoid valves EV 1 and EV 2, for example, capable of: in the presence of said slippage, issuing said command I 1 and I 2 to force the decrease of the brake force, once said slippage has stabilized, issuing said command to lock the brake force at its current value (I 1 and not I 2), in the absence of said slippage, issuing said command (not I 1 and not I 2) to force the increase of the brake force up to the value corresponding to the pressure regulator reference 12.

[0058] The forced regulation module 22 is further configured to transform said acquired order into a forced regulation command which takes priority over the electronic command supplied at the output by the electronic pressure regulator 12 and is intended for said pair of solenoid valves EV 1 and EV 2.

[0059] As an alternative not shown, the forced regulation module 22 is further configured to transform said acquired order into a forced regulation command supplied as input to the electronic pressure regulator 12. In other words, according to this variant not shown on the figure 2 It is also possible to have the outputs of module 22 act directly on the reference pressure (input of module 12) and not on the output of module 12.

[0060] In other words, according to this second optional variant, the secure electronic control device 10 has two additional inputs, namely the separate commands I 1 and I 2 to prevent admission, or to force exhaust.

[0061] These inputs I1 and I2 are typically used during the implementation of a WSP wheel slip protection algorithm (from English Wheel Slide Protection) by the external electronic brake control unit 24 (also called the brake electronic control equipment set (BCE)) in order to force the release of the brake (i.e., the release of air) when slippage is detected, which bypasses (overrides by taking priority over) the output of the pressure regulator 12 as illustrated by the figure 2 where the outputs of the forced regulation module 22 are capable of modifying downstream the outputs of the pressure regulator 12.

[0062] When the slip has disappeared, the WSP wheel slip protection algorithm then allows the regulator 12 to quickly restore the braking pressure in the brake caliper cylinder E.

[0063] To ensure safety, the command to force the inlet solenoid valve EV 1 to the closed state is ignored if it lasts, for example, more than fifteen seconds, in accordance with the standard requirement of EN15595. This duration can be configured, for example, by means of a threshold value well below fifteen seconds, and a "watchdog fault" W (from English watchdog fault) is generated and transmitted by the electronic safety card of the electronic device 10, to be used, for example, by the TCMS train control and monitoring system (from English Train Control and Monitoring System). Optionally, the same applies if the command to force the exhaust solenoid valve EV 2 to the open state lasts longer than ten seconds. Furthermore, if a command to force the exhaust solenoid valve EV 2 to the open state (I 2) is received without a command to force the intake solenoid valve EV 1 to the closed state (I 2 and not I 1), which would risk emptying the brake fluid reservoir to the atmosphere, then these commands will be ignored.

[0064] Such a second optional variant makes it possible to remove the solenoid valve classically called a "dump valve" (in English "dump valve") traditionally used for protection against wheel slippage in WSP.

[0065] According to a third optional variant that complements the previous variant, the control device 10 further includes a hysteresis module 26 configured to: compare the value of the first electrical signal to a predetermined threshold representing a limit before overpressure within said caliper, and in case of exceeding said threshold, generate a pressure release order, which takes priority over the forced regulation command, and is sent to said pair of solenoid valves.

[0066] In other words, according to this third variant, an additional electronic function is implemented in the safety electronic board of the control device 10. This electronic function, implemented via the hysteresis module 26, will force the release of air if the measured pressure exceeds a given threshold with a predetermined hysteresis. This optional third variant protects the caliper E against overpressure in the brake cylinder, which could damage it. This function provides additional safety and can also replace the pressure reducer RP, which is usually mounted after the brake reservoir RF.

[0067] A fourth optional complementary variant is offered in particular for railway rolling stock, some of whose brake calipers are called "parking brake calipers", because they incorporate additional features to keep the railway rolling stock stationary even when there is no more pressure available on the railway rolling stock, i.e. when the railway rolling stock is parked for a long time, for example several hours.

[0068] Generally, about half of all brake calipers are parking brake calipers. Standard brake calipers have only one brake cylinder, a direct type, with the braking force proportional to the pressure applied. Parking brake calipers have two brake cylinders: one direct (like standard brake calipers) and one indirect, with the braking force inversely proportional to the pressure, thanks to an additional spring.

[0069] When railway rolling stock is parked for an extended period, all pneumatic circuits are at atmospheric pressure, and the braking force is provided by the spring, thus preventing any movement of the rolling stock (i.e., the train). During the movement of the rolling stock (e.g., the train), the indirect cylinder is pressurized to counteract the spring force, and the brake is controlled solely by the direct cylinder, as with standard brake calipers. With this design, there is a risk that both cylinders could generate force simultaneously, potentially damaging the caliper. To prevent this, an anti-compounding valve is typically added to prevent pressure from being applied to the direct cylinder when there is no pressure in the indirect cylinder.

[0070] The fourth optional variant proposed here aims to eliminate the "anti-compound" valve by replacing it with an additional function in the electronic safety board. To achieve this, the control device 10 further includes, connected to an external pressure switch 28 (i.e., pressure switch 28), a fourth acquisition module 30 configured to: receive a signal, emitted by the external switch 28, representative of the absence of pressure in an indirect cylinder when the brake caliper is a parking brake caliper comprising two brake cylinders: a direct cylinder dedicated to braking outside parking and an indirect cylinder dedicated to parking braking of railway rolling stock; generate a pressure release order, which has priority over the forced regulation command, and is intended for said pair of solenoid valves.

[0071] In other words, thanks to the pressure switch 28 indicating the absence of pressure in the indirect cylinder, the electronic safety board of the regulating device 10 will force the air to escape into the direct cylinder to avoid the superposition of forces.

[0072] As an alternative, not shown, the pressure switch 28 of the system illustrated by the figure 2 is replaced by another pressure transducer.

[0073] As illustrated on the figure 2 , according to a particular aspect the electronic safety card of the regulation device 10 further includes a module 32 corresponding to a logical OR to generate a release order 34, which has priority over the forced regulation command, issued by the hysteresis module 26 or by the fourth acquisition module 30.

[0074] As an alternative to the aforementioned fourth supplementary optional variant, according to a fifth supplementary optional variant, not shown, the electronic command issued by default to said pair of solenoid valves is a pressure admission command, when the brake caliper includes a direct cylinder dedicated to service braking and emergency braking, or a pressure release command, when the brake caliper is a parking brake caliper comprising only an indirect cylinder dedicated to both service braking, emergency braking and / or the parking brake.

[0075] This fifth variant of the electronic device 10 allows for a further simplification of the parking brake caliper by removing the direct cylinder of the parking brake caliper, the indirect brake cylinder then being used for both the service brake and the emergency brake.

[0076] According to this fifth variant, the aforementioned operation of the regulation device 10 remains the same except that it requires that the default state of the solenoid valves EV 1 and EV 2 must be exhaust to the atmosphere, and an inversion of the binary logic values ​​(zero and one) of the commands C 1 and C 2, with in particular the value one for air intake and the value zero for exhaust, so that the result of the electronic command issued by default results in an application of force by the caliper.

[0077] This fifth variant also allows the removal of the "anti-compound" valve and reduces the cost of the parking brake caliper, which then only includes a single brake caliper.

[0078] According to a sixth optional complementary variant, the control device 10 further includes a timer module 36 configured to establish a minimum transition time between two distinct states of the pair of solenoid valves, said two distinct states being associated with the application of two separate electronic commands.

[0079] In other words, according to this sixth optional variant, an additional electronic function is added to the electronic safety board of the control device 10 to ensure that the solenoid valves EV 1 and EV 2 are not activated and deactivated too rapidly, specifically by verifying a minimum activation time and a minimum deactivation time. This sixth optional variant also ensures that a minimum transition time is maintained between the intake and exhaust of air, and vice versa.

[0080] More specifically, module 36 uses at least three parameters, for example: t_off_min corresponds to the minimum time during which the solenoid valve remains closed (i.e., the solenoid valve command must remain at zero for at least t_off_min); t_on_min corresponds to the minimum time during which the solenoid valve remains open (i.e., the solenoid valve command must remain at one for at least t_on_min); t_dead corresponds to the minimum time between the closing of EV1 (respectively EV2) and the opening of EV2 (respectively EV1) => we can never open the two solenoid valves simultaneously, therefore we pass through a minimum time (t_dead) during which the two solenoid valves are closed.

[0081] This sixth optional complementary variant thus optimizes the lifespan of the EV 1 and EV 2 solenoid valves, as well as reducing the need for maintenance.

[0082] According to a seventh optional variant, the control device 10 further includes a duplicated emergency braking input and a second load compensation module 38 associated with said duplicated emergency braking input. Such a seventh optional variant is suitable for use in certain markets (high-speed trains, for example) requiring two levels of effort because adhesion varies with speed (braking is less forceful at high speed), hence the duplication of the "emergency braking" inputs: the first will be applied first, then the second once the speed has dropped below a certain threshold.

[0083] As with the load compensation module 20, if the pressure in the suspension (measured by TP2) is outside the design range, default pressures are applied, which may differ between modules 20 and 38. This can occur, for example, if the TP2 sensor is faulty or if the air spring is punctured. In other words, the linear load pressure compensation function is clipped at its upper and lower limits to guard against an aberrant suspension pressure measurement.

[0084] Such a seventh optional complementary variant is also suitable for use in obtaining an FP (Fixed Position Braking) function (i.e., a safety-holding function). holding brake) Used to hold railway rolling stock (e.g., a train) at a standstill for a short period, usually in stations. Typically, the parking brake is achieved by applying the service brake and cutting off traction (for safety reasons). Thanks to the safety provided by the electronic safety card 10, the level of safety required for cutting off traction can be reduced.

[0085] According to an eighth optional variant, the input and acquisition of the signal for the service brake pressure reference are duplicated and represented by input 40 and the acquisition module 42. The second input 40 corresponds, for example, to the backup service brake pressure reference provided by another set of electronic brake control equipment (EBC) or provided by the pressure in the main brake line (as defined in EN 14478). Such an input 40 is suitable for use, according to this variant, for example, in the event of a failure of the control electronics 24 that generates input 15, to increase the overall availability of the system, which is particularly required in the Indian railway market today.

[0086] Input 40 can also be used to emulate (i.e., replace) the traditional brake distributor by adding a pressure transducer that measures the pressure in the main brake line, as found on conventional trains, which comply with UIC or AAR braking standards, for example. This pressure is distributed throughout the train. The pressure in the main brake line is inversely proportional to the braking force applied by the driver. The distributor's role is to generate the pressure for the brake caliper cylinder from the pressure in the main brake line. Distributors are generally heavy and expensive components. This eighth optional variant allows the distributor to be replaced by a simple pressure transducer connected to the secure electronic control board.

[0087] It should be noted that the electronic safety card 10 aims to give priority to emergency braking over the rest, (i.e. FU has priority over FP which itself has priority over the aforementioned inputs 15 and 40), and to do this also includes a comparator 44 configured to determine the input with the maximum value among the inputs 15 and 40, the output of comparator 44 then being connected to two switches connected respectively to the outputs of the load compensation modules 20 and / or 38 in order to use FU as a priority when emergency braking is required, then in order of priority the parking brake FP (in the absence of emergency braking required) then the input with the maximum value among the inputs 15 and 40 (in the absence of emergency braking FU or parking braking FP) to define the reference pressure to be used.

[0088] As an alternative not shown, comparator 44 is located after (i.e., downstream of) the two switches. The effect is similar to the upstream location represented by the figure 2 , since the effort in emergency braking is greater than the effort in service braking.

[0089] According to a ninth optional variant, the control device 10 further includes a self-test module 46 configured to automatically initiate a self-test of said device, and / or a self-test of the solenoid valve pair EV 1 and EV 2, and / or of said brake caliper E. In other words, according to this ninth optional variant, an additional electronic function is added to the safety electronic board to perform a self-test of the board, the solenoid valves EV 1 and EV 2, and the brake caliper E. This further increases the level of safety integrity of the electronic board 10 constituting the control device. The self-test is initiated automatically each time the safety electronic board 10 is powered on or can be initiated by external control electronics 24 as illustrated by order 45 on the figure 2 .

[0090] According to a tenth optional supplementary variant, the electronic control device 10 further includes a fault monitoring module 48 configured to at least monitor the device's own internal power supply, and to transmit 50 of this monitoring result to an external control electronic 24 to be consolidated with other information on the health status of the railway rolling stock (i.e. train) braking system.

[0091] In other words, according to this tenth optional variant, the secure electronic card 10 includes an additional fault monitoring function, such as monitoring its internal power supply. This function helps diagnose problems during testing and / or during commercial service (i.e., operation with passengers).

[0092] According to an eleventh optional supplementary variant, the electronic control device 10 further comprises an accelerometer 52 configured to measure the longitudinal acceleration of said railway rolling stock, and a combination module 54 configured to combine said longitudinal acceleration with a speed of said railway rolling stock provided by the external electronic brake control unit 24 of said electronic device 10 and generate a consolidated speed suitable for use at least by said load compensation module 20.

[0093] In other words, according to this eleventh optional variant, the accelerometer 52 is optionally added to the safety electronic board 10. The integration of the longitudinal acceleration delivered by the accelerometer, combined with the speed 53 provided by the BCE brake control electronics 24 (or directly from a speed transducer not shown), is used to generate, via the combination module 54, a reliable speed reference. This reliable speed reference is then used by the load compensation module 20 to adapt the pressure reference in the emergency brake according to the speed. A variable brake pressure reference is advantageously suited for use in obtaining a variable braking force in the emergency brake in order to cope with the wheel-rail adhesion coefficient, which changes with speed, as required by the technical specifications for TSI interoperability. Technical Specifications for Interoperability). Such a variable brake pressure reference can also be used to compensate for the coefficient of friction, for example between the brake disc and pad, which also depends on speed.

[0094] According to a twelfth optional variant, the secure electronic card constituting the electronic control device 10 refers to another control electronic, for example to the BCE brake control electronic 24, with data such as those listed below by way of non-limiting example: the pressure measured in the brake caliper cylinder E, the control of the solenoid valves EV 1 and EV 2, the pressure in the suspension bellows S, particularly when the first optional variant of the figure 2 is implemented; the state of the parking brake caliper (also called parking brake) if the fourth supplementary optional variant is used, or the pressure in the indirect cylinder of the parking brake caliper if the pressure switch 28 of the system according to this variant is replaced by a pressure transducer; the accelerations in the three directions x, y, z of a predetermined frame of reference in particular when the eleventh supplementary optional variant is used; various monitoring data if the tenth supplementary optional variant is used.

[0095] Such feedback implemented by the electronic control device 10 allows the development of all kinds of more complex functions in the control electronics, such as protection against traction slip (from English slip), or in braking against wheel lock or slippage (from English) slide ) of the wheels, in particular according to standard EN14478, load compensation for the service brake, condition-based maintenance, predictive maintenance, brake coupling, slope compensation, etc. In other words, such feedback allows the development of any type of function not related to safety, or with a lower level of safety integrity, without redesign / recertification of the secure electronic board of the electronic device 10.

[0096] As an alternative, according to such a twelfth optional variant, the exchange of data, including the pressure reference for the service brake, between the safety electronic board 10 and the control electronics 24 is carried out via a network, for example a CAN network from English Controller Area Network, which reduces the wiring.

[0097] According to a thirteenth optional supplementary variant, said first pressure transducer TP 1 and / or said second pressure transducer TP 2, and / or the external pressure switch 28 (i.e. pressure switch 28) are directly integrated into said electronic device using a pneumatic tube connected directly between said device and respectively said caliper E and / or said suspension S.

[0098] In other words, the pressure transducers described earlier are directly integrated into the secure electronic board 10. Specifically, a pneumatic tube is connected directly between the secure electronic board 10 and the pressure to be measured. This simplifies mechanical integration on the component side, while minimizing additional complexity on the secure electronic board itself. It also allows the pressure transducers to be removed from areas highly susceptible to electromagnetic interference, thus facilitating the demonstration of EMC compatibility.

[0099] The secure electronic card 10 according to the present invention makes it possible to implement the redundancies necessary to guarantee the level of safety integrity required for emergency braking by redundantly associating a secure electronic card 10 (i.e. a pressure regulation device according to the present invention) with each brake caliper or group of brake calipers.

[0100] According to an aspect not shown, it should be noted that the secure electronic card 10 (i.e., a pressure regulating device according to the present invention) is designed in such a way that any failure, or most of them, such as a failure of the power supply, systematically leads to the admission of air into the brake cylinder (or to the exhaust if it is an indirect brake cylinder as in the fifth variant), controlled for example by an electronic signal of zero binary value (i.e., a bit with a value of zero), and resulting in the application of a braking force.

[0101] Furthermore, in a safe manner, the secure electronic boards 10 (i.e. a pressure regulating device according to the present invention) associated with each brake caliper or group of brake calipers do not have a common mode of failure (i.e. are independent), in other words the pressure regulating device is designed so that a failure in one device does not cause a failure in another device.

[0102] One of the classic common modes, particularly for the pneumatic brake control system, is the emergency brake control FU. To avoid this, when the emergency brake line drops to zero (its most probable failure mode), the secure electronic board 10 is configured to systematically apply the emergency brake.

[0103] Another common and classic cause is the design of the circuit board itself. Because the design of the secure electronic circuit board is the same for all boards, a design flaw can lead to the same failure on all boards simultaneously. This pitfall is avoided through standardized testing and the application of norms, as is typically done for air brake control systems.

[0104] To guarantee a level of security integrity (SIL) safety integrity levelThe regulation system according to the present invention is designed so that for solenoid valves EV 1 and EV 2, if there is no command, i.e., a zero command, which occurs, for example, in the event of a power failure to the safety electronic board, the upper solenoid valve EV 1 will be open by default, and the lower solenoid valve EV 2 will be closed. In other words, the (direct) brake cylinder will be directly connected to the reservoir, thus resulting in braking. In the fifth variant, the opposite occurs: the (indirect) brake cylinder is vented to atmosphere, which also results in braking.

[0105] It should be noted that it is possible to achieve the highest level of security (SIL4) by means of redundant and diversified software or of software redundant by an FPGA, which amounts to software control but control of the result via another device (i.e. non-software).

[0106] The pressure regulator 12 is also designed so that in the event of a component failure, the air intake will be the default control (respectively the exhaust in the case of the fifth variant).

[0107] If the train line "Emergency Brake" FU falls to zero, its most probable failure case, the pressure regulator 12 is configured to regulate the default pressure reference required for emergency braking.

[0108] The pressure transducer T P1 normally delivers an electrical signal with a current between 4 and 20mA. An abnormal current (typically 0mA) is likely to be detected by the safety electronic board 10, and interpreted as insufficient pressure, which will force the upper solenoid valve EV 1 to admit more air.

[0109] The optional load compensation module 20 (and consequently the acquisition module 18, the accelerometer 52 and the combination module 54 which provide it with input data) is designed so that in the event of a failure, a default pressure (corresponding to the maximum braking pressure, for example) is generated and used as a reference by the pressure regulator 12.

[0110] The optional forced regulation module 22 ensures that the WSP algorithm cannot prevent air intake or force air exhaust (which would reduce braking force) for more than 10 seconds (as required by standards). The optional forced regulation module 22 is designed so that in the event of a failure, the output of the pressure regulator 12 is used by default to control solenoid valves EV 1 and EV 2.

[0111] Failure modes of other modules not having a direct impact on safety such as acquisition module 16 used only for service braking, which is not safety-related, are also analyzed to ensure that they cannot negatively affect the other aforementioned modules ensuring the safety of railway rolling stock.

[0112] A person skilled in the art will understand that the invention is not limited to the embodiments described, nor to the particular examples of the description, the embodiments and variants mentioned above being capable of being combined with each other to generate new embodiments of the invention, which is defined in the claims.

[0113] Thus, the present invention proposes an electropneumatic architecture for brake control, which allows most of the pneumatic components of the brake control to be replaced by equivalent electronic components, even for safety functions such as emergency braking. In the invention, all pneumatic components are used for both service braking and emergency braking, which makes it possible to limit the pressure regulation to a pair of solenoid valves, and the level of safety integrity required for emergency braking is ensured by a secure electronic board constituting the proposed electronic control device 10.

Claims

1. Electronic device (10) for regulating the pressure supplied to a pneumatic cylinder brake calliper (E) of a railway rolling stock via a pair of solenoid valves comprising an upper solenoid valve (EV1) for increasing pressure and a lower solenoid valve (EV2) for relieving pressure, the said electronic device comprising an electronic pressure regulator (12) configured for: - checking the said pair of solenoid valves via at least one electronic control by continuously comparing a first electrical signal representative of the pressure measured within the said calliper with a second electrical signal representative of a reference pressure, and - controlling the opening of: - the upper intake solenoid valve (EV1) when the value of the first electrical signal is lower than that of the second electrical signal, or - the lower exhaust solenoid valve (EV2) when the value of the first electrical signal is greater than that of the second electrical signal; the said electronic device (10) being characterised in that: in the presence of an emergency braking request, the said second electrical signal representative of a reference pressure corresponding to an electrical signal representative of the pressure value needed for the emergency braking of the said rolling stock, in the absence of an emergency braking request, the said second electrical signal representative of a reference pressure corresponding to an electrical signal obtained from at least one service braking input of the said device (10) supplied by at least one electronic control unit external to the said electronic device (10) and / or supplied by a train control and monitoring system.

2. Electronic device (10) according to Claim 1, wherein the said electronic device further comprises: - a first acquisition module (14) configured for: - receiving the said first electrical signal representative of the said measured pressure, the said first electrical signal being supplied by a first pressure transducer external to the said electronic device (10), the said first pressure transducer being capable of transforming the pressure measured within the said calliper into the said first electrical signal, and - supplying the said first electrical signal to the input of the said electronic regulator (12), - a reconfigurable memory space (PD) configured for: - storing the said electrical signal representative of the pressure value needed for the emergency braking of the said railway rolling stock, - supplying the said electrical signal representative of the pressure value needed for the emergency braking to the input of the said electronic regulator (12) in the presence of an emergency braking request, - at least one second acquisition module (16, 42) configured for: - receiving and / or generating the said electrical signal obtained from at least one service braking input of the said device (10) supplied by at least one electronic control unit external to the said electronic device (10) and / or supplied by a train control and monitoring system, and - supplying the said electrical signal obtained to the input of the said electronic regulator (12) in the absence of an emergency braking request.

3. Electronic device (10) according to any one of Claims 1 or 2, further comprising: - a third acquisition module (18) configured for: - receiving a third electrical signal representative of the pressure measured within a suspension (S) associated with the said brake calliper (E), the said third electrical signal being supplied by a second pressure transducer external to the said electronic device (10), the said second pressure transducer being capable of transforming the pressure measured within the said suspension (S) into the said third electrical signal, and - supplying the said third electrical signal to the input of at least one load compensation module (20, 38), - at least one load compensation module (20, 38) configured for determining the pressure value needed for emergency braking, or needed for immobilisation braking of the said railway rolling stock, depending on the load of the said railway rolling stock of which the third electrical signal is representative.

4. Electronic device (10) according to Claim 2 or Claim 3, wherein the said first pressure transducer and / or the said second pressure transducer are integrated directly into the said electronic device using a pneumatic tube connected directly between the said device and respectively the said calliper and / or the said suspension (S).

5. Electronic device (10) according to any one of Claims 2 to 4, further comprising a forced regulation module (22) configured for acquiring at least two distinct types of commands for: - forcing the intake solenoid valve (EV1) into the closed state, or - forcing the exhaust solenoid valve (EV2) into the open state, the said at least two commands being issued by an electronic brake control unit (24) external to the said electronic device (10), the said electronic brake control unit (24) being capable of detecting a sliding of the wheels of the said rolling stock, and of controlling the said sliding by means of the said forcing commands for the solenoid valves (EV1 and EV2), the said forced regulation module (22) being further configured for transform the said acquired command into a forced regulation command which has priority with respect to the electronic command supplied as output by the electronic pressure regulator (12) and is intended for the said pair of solenoid valves.

6. Electronic device (10) according to Claim 5, further comprising a hysteresis module (26) configured for: - comparing the value of the first electrical signal with a predetermined threshold representative of a limit before overpressure within the said calliper, and - if the said threshold is exceeded, generating a pressure relief command which has priority over the forced regulation command and is intended for the said pair of solenoid valves.

7. Electronic device (10) according to Claim 5 or 6, further comprising a fourth acquisition module (30) configured for: - receiving a signal representative of the absence of pressure in an indirect cylinder when the brake calliper is a parking brake calliper comprising two brake cylinders: a direct cylinder dedicated to non-parking braking and an indirect cylinder dedicated to parking braking of the railway rolling stock; - generating a pressure relief command, which has priority over the forced regulation command and is intended for the said pair of solenoid valves.

8. System for regulating the pressure supplied to a pneumatic cylinder brake calliper (E) of a railway rolling stock via a pair of solenoid valves comprising an upper solenoid valve (EV1) for increasing pressure and a lower solenoid valve (EV2) for relieving pressure, the system comprising at least: - an electronic device (10) according to any one of the preceding claims; - the said pair of solenoid valves.

9. Electronic system according to the preceding claim, further comprising a relay valve having a 1:1 regulation ratio, the said relay valve being located between the pair of solenoid valves and the pneumatic cylinder brake calliper, the pair of solenoid valves being configured for generating a pilot pressure intended for the said relay valve, which is in turn configured for then amplifying the output flow rate, according to a predetermined amplification, for the pneumatic cylinder brake calliper (E).

10. Railway rolling stock comprising a system according to one of the preceding Claims 8 and 9.