Braking system with leak monitoring and emergency parking relief function

Abstract

The application provides a brake system with leakage monitoring and emergency parking relief function, comprising a brake control device provided with a normal brake pressure sensor and a parking pressure sensor, which respectively collect the total air pressure of a relay valve input pipeline and the parking brake pressure output by an emergency parking relief execution unit, and an electronic control unit obtains pressure data of each vehicle in a train set through a train network and identifies pipeline leakage and locates a fault vehicle in combination with two detection values. A gas source distribution unit accesses total air and divides a brake branch and a parking branch. The emergency parking relief execution unit is provided with an isolation plug valve, a double-position air control valve, an electric control relief electromagnetic valve and an electric contact side exhaust plug valve. The isolation plug valve is used for cutting off the parking air path of the fault vehicle to realize single vehicle isolation. An emergency air cylinder is connected to the second air inlet of the air control valve through a pressure maintaining one-way valve.

Description

Technical Field

[0001] This application relates to the field of braking control technology for rail transit vehicles, and more particularly to a braking system with leakage monitoring and emergency parking relief functions. Background Technology

[0002] Parking braking is achieved by the spring in the parking cylinder of the brake caliper outputting braking force and pressing the friction pair together; it is a pure spring brake. Whether it's the service brake or the parking brake, an air pipeline needs to be installed under the train to input pressurized air from upstream into the brake cylinder and parking cylinder to achieve normal brake release function.

[0003] When the undercarriage piping leaks severely due to impacts from foreign objects, the total air pressure will drop rapidly, causing the regular brakes to fail to apply and the parking brakes to fail to release quickly. In this situation, if a forced rescue is attempted without interrupting power, the inability to release the brakes on the vehicle while it is parked will result in smoke and odors, causing greater panic among passengers. If a power outage is requested before rescue, it will prolong the rescue time and significantly impact the restoration of normal operations. If the malfunction occurs in a narrow underground section or tunnel, the situation becomes even more challenging, as there may not be enough space to manually release the brakes under each bogie even after a power outage.

[0004] Currently, mainstream train braking systems are equipped with some pressure sensors, whose collected values ​​serve as the basis for common braking calculations or corrections. However, to address the aforementioned issues, the braking system needs to have single-car air leakage monitoring and single-car isolation capabilities. Parking brakes require a dedicated module to handle emergency parking situations, necessitating a redesign of the braking system's air circuitry and the addition of leakage warning logic. This invention can proactively locate and warn faulty vehicles in advance of pipe leaks, enabling timely single-car isolation. Onboard, it allows for both automatic and manual emergency parking of single cars or the entire train, automatically towing them to safety without the need for rescue. Summary of the Invention

[0005] The purpose of this application is to provide a braking system with leakage monitoring and emergency parking relief functions, in order to solve the problems of existing braking systems that cannot monitor the leakage location in real time when leakage occurs in the under-vehicle pipeline, cannot quickly isolate the leaking vehicle, and cannot quickly relieve parking brakes on the vehicle, thus requiring external assistance.

[0006] To achieve the above objectives, the braking system with leakage monitoring and emergency parking relief functions provided in this application is applied to locomotives and rolling stock equipped with spring parking cylinders. Specifically, it includes a braking control device, an air supply distribution unit, an emergency parking relief execution unit, and an emergency air cylinder. The braking control device includes a relay valve, an electronic control unit, a service brake pressure sensor, and a parking pressure sensor. The detection end of the service brake pressure sensor is connected to the input pipeline of the relay valve, and the detection end of the parking pressure sensor is connected to the output pipeline of the emergency parking relief execution unit via a pressure-sensing pipeline. The signal output ends of both the service brake pressure sensor and the parking pressure sensor are electrically connected to the electronic control unit. The electronic control unit acquires pressure data of each car in the train formation through the train network, and combines the detection values ​​of the service brake pressure sensor and the parking pressure sensor to identify pipeline leaks and locate faulty vehicles. The air supply distribution unit connects to the main air supply and branches out a braking branch and a parking branch. The braking branch connects to the input end of the relay valve, and the parking branch connects to the first air intake of the emergency parking relief execution unit. The emergency parking relief actuator's outlet is connected to the parking cylinder. Internally, it is equipped with an isolation plug, a dual-position pneumatic control valve, an electrically controlled relief solenoid valve for switching positions, and an exhaust plug on the live contact side, all connected in series with the emergency parking branch input path. The isolation plug is connected in series with the emergency parking branch input path. The output of the electrically controlled relief solenoid valve is connected to the pre-control terminal of the dual-position pneumatic control valve, used to drive the dual-position pneumatic control valve to switch positions. The first air inlet of the dual-position pneumatic control valve is connected to the parking branch, and the second air inlet of the dual-position pneumatic control valve is connected to the pressure holding point. The pipeline between the one-way valve and the emergency air cylinder; the emergency parking branch downstream of the isolation plug is connected to the emergency air cylinder through an inflation pipeline with a pressure-holding one-way valve, with the pressure-holding one-way valve's conduction direction facing the emergency air cylinder; the energized contact side exhaust plug is connected in series downstream of the dual-position pneumatic control valve's output port, and its side exhaust port is connected to the pipeline between the pressure-holding one-way valve and the emergency air cylinder, used for manual operation of the plug to relieve parking braking in an emergency; the energized contact end of the energized contact side exhaust plug is connected to the driver's cab display terminal through a vehicle hardwire, used to provide feedback on the plug's position status.

[0007] In the aforementioned braking system with leakage monitoring and emergency parking release functions, optionally, the braking control device further includes an air charging solenoid valve, an air exhaust solenoid valve, and a pre-control pressure sensor; the air charging solenoid valve, the air exhaust solenoid valve, and the pre-control pressure sensor are all electrically connected to the electronic control unit; the air charging solenoid valve and the air exhaust solenoid valve are connected in series in the pre-control air path of the relay valve, and the detection end of the pre-control pressure sensor is connected to the pre-control interface of the relay valve; the electronic control unit calculates the target brake cylinder pressure according to the vehicle load, charges air into the pre-control interface of the relay valve through the air charging solenoid valve, collects the pre-control pressure through the pre-control pressure sensor and forms a closed-loop control, and outputs the corresponding pressure to the vehicle brake cylinder through the relay valve; and, when the brake is released, the electronic control unit controls the air exhaust solenoid valve to open to the atmosphere, so that the pressurized air in the brake cylinder is discharged through the relay valve.

[0008] In the aforementioned braking system with leakage monitoring and emergency parking relief functions, optionally, the braking control device further includes a parking pressure acquisition board and matching internal and external wiring harnesses; the parking pressure sensor is connected to the signal input terminal of the electronic control unit through the parking pressure acquisition board, and the common braking pressure sensor is connected to the braking pressure acquisition channel of the braking control device.

[0009] In the aforementioned braking system with leakage monitoring and emergency parking relief functions, optionally, the electronic control unit has a built-in leakage judgment logic unit; the leakage judgment logic unit identifies leakage faults and locates the corresponding vehicles by comparing the parking pressure values ​​of each vehicle in the group with the total air pressure value and the pressure deviation and pressure drop status; based on the identification results, it generates a warning signal and outputs it to the display terminal in the vehicle driver's cab.

[0010] In the aforementioned braking system with leakage monitoring and emergency parking relief functions, optionally, the leakage judgment logic unit is configured to: receive real-time data on the total air pressure and parking pressure of the train, and synchronously acquire the corresponding pressure data of other cars in the train formation through the train network; based on the second highest pressure value of the same type in the train formation, filter out abnormal cars whose pressure value deviation exceeds a preset threshold; compare the pressure drop time difference between the total air pressure and parking pressure of the abnormal cars, and combine the pressure drop rate per unit time to determine whether the leakage occurs in the total air branch, parking branch, or parking cylinder side pipeline; generate a corresponding level of early warning signal according to the leakage location and pressure drop level and output it to the driver's cab display terminal.

[0011] In the aforementioned braking system with leakage monitoring and emergency parking release functions, optionally, the braking control device further includes an air-load valve, an emergency solenoid valve, a forced release solenoid valve, and a forced release pneumatic control valve; the input end of the air-load valve is connected to the air spring pressure, and the output end of the air-load valve is connected to the emergency pre-control interface of the relay valve; the emergency solenoid valve is controlled by the electronic control unit, and when it is turned on, the relay valve outputs emergency braking pressure to the brake cylinder; the forced release solenoid valve is controlled by the electronic control unit; the pre-control end of the forced release pneumatic control valve is connected to the output end of the forced release solenoid valve, and when it is turned on, it cuts off the upstream of the braking branch and connects the brake cylinder side passage to the atmosphere.

[0012] In the aforementioned braking system with leakage monitoring and emergency parking relief functions, optionally, the air source distribution unit is equipped with a filter with a one-way valve. After the main air passes through the filter, it is divided into a braking branch and a parking branch. A pressure reducing valve and a dual-pulse solenoid valve are connected in series on the parking branch. The outlet pressure of the pressure reducing valve is adjusted to be higher than the outlet pressure of a conventional pressure reducing valve, so as to cooperate with the parking pressure sensor to realize leakage monitoring in advance in the high-pressure range.

[0013] In the aforementioned braking system with leakage monitoring and emergency parking relief functions, optionally, the emergency parking relief actuator adopts an integrated air circuit board structure, wherein the isolation plug, the dual-position air control valve, the electrically controlled relief solenoid valve, and the energized contact side exhaust plug are all plate-type valves and are integrated and installed on the integrated air circuit board; the emergency parking relief actuator is installed inside the vehicle passenger compartment, and each vehicle is separately configured.

[0014] In the aforementioned braking system with leakage monitoring and emergency parking relief functions, optionally, the control end of the electronically controlled relief solenoid valve is extended to the control knob of the driver's cab electrical cabinet. By operating the control knob, the electronically controlled relief solenoid valve is energized or de-energized, thereby driving the dual-position pneumatic control valve to switch the conduction position.

[0015] In the aforementioned braking system with leakage monitoring and emergency parking relief functions, optionally, the dual-position pneumatic control valve is a two-position three-way pneumatic control valve; under normal operating conditions, the electrically controlled relief solenoid valve is de-energized, and the dual-position pneumatic control valve is in the first position, with the first air inlet and outlet connected and the second air inlet closed; under emergency operating conditions, the electrically controlled relief solenoid valve is energized, and the dual-position pneumatic control valve switches to the second position, with the second air inlet and outlet connected and the first air inlet closed.

[0016] In the aforementioned braking system with leakage monitoring and emergency parking relief functions, optionally, the energized contact side exhaust valve serves as a channel for the air path under normal operating conditions, connecting the upstream and downstream air paths; under emergency operating conditions, the energized contact side exhaust valve cuts off the upstream air path and connects the downstream and side exhaust vents.

[0017] The beneficial technical effects of this application are as follows: By adding a parking pressure sensor to the braking control device and comparing it with the pressure data of commonly used braking pressure sensors and train network formation, real-time monitoring of pipeline leakage and accurate location of faulty vehicles are achieved, solving the problem that existing systems cannot provide early warning of leakage faults; by setting an isolation valve connected in series with the emergency parking branch, the parking air circuit of the faulty vehicle can be cut off in time when leakage occurs, preventing leakage from continuously affecting the total air pressure of the entire vehicle; by setting a dual-position air control valve and an emergency air cylinder, and configuring a pressure-holding one-way valve, the emergency air cylinder can still maintain a pressure-storing state when the total air pressure drops. It can achieve remote electronic emergency relief of the entire train or a single car through the driver's cab via an electronically controlled solenoid valve, and can also achieve manual mechanical relief through the side exhaust air valve. The dual redundancy design ensures that the parking brake can still be quickly released after the total air pressure is lost, so that the faulty train can be towed to a safe handling area without the need for external rescue vehicles, which greatly improves the efficiency of handling leakage faults and the safety of train operation. Attached Figure Description

[0018] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the overall air circuit structure of a braking system with leakage monitoring and emergency parking relief functions provided in an embodiment of this application; Figure 2 A detailed pneumatic circuit diagram of an emergency parking mitigation unit provided in an embodiment of this application; Figure 3 This is a block diagram of the braking system leakage monitoring and emergency mitigation control logic provided in an embodiment of this application. Detailed Implementation

[0019] The following will describe in detail the implementation methods of this application with reference to the accompanying drawings and embodiments, so as to fully understand how this application uses technical means to solve technical problems and achieve technical effects, and to implement it accordingly. It should be noted that, as long as there is no conflict, the various embodiments and features in each embodiment of this application can be combined with each other, and the resulting technical solutions are all within the protection scope of this application.

[0020] Furthermore, the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0021] In the description of this application, the terms "upstream" and "downstream" are relative to the direction of compressed air flow; the side closer to the air source (main air inlet) is upstream, and the side farther from the air source is downstream. The term "open" means that the air path is in a connected state, allowing compressed air to flow in the pipeline; the term "closed" means that the air path is in a closed state, preventing compressed air from passing through. The term "pre-control end" refers to the interface on the pneumatic control valve or relay valve used to connect the pilot control pressure. The control pressure introduced through this interface can drive the valve core to actuate, thereby switching the operating state of the main air path of the valve body.

[0022] In one embodiment of this application, a braking system with leakage monitoring and emergency parking relief functions is provided, which is applied to locomotives and rolling stock equipped with spring parking cylinders. The system includes a braking control device, an air source distribution unit, an emergency parking relief execution unit, and an emergency air cylinder. The braking control device includes a relay valve, an electronic control unit, a common brake pressure sensor, and a parking pressure sensor. The detection end of the service brake pressure sensor is connected to the input pipeline of the relay valve, and the detection end of the parking pressure sensor is connected to the output pipeline of the emergency parking relief actuator via the pressure tapping pipeline. The signal output ends of both the service brake pressure sensor and the parking pressure sensor are electrically connected to the electronic control unit. The electronic control unit obtains the pressure data of each car in the train formation through the train network, and combines the detection values ​​of the service brake pressure sensor and the parking pressure sensor to identify pipeline leaks and locate the faulty car. The air source distribution unit is connected to the main air supply and splits into a braking branch and a parking branch. The braking branch is connected to the input terminal of the relay valve, and the parking branch is connected to the first air inlet of the emergency parking relief execution unit. The emergency parking relief execution unit has an air outlet connected to the parking cylinder and is internally equipped with an isolation plug, a dual-position pneumatic valve, an electrically controlled relief solenoid valve that drives the switching position, and an exhaust plug with live contacts connected in series with the input path of the emergency parking branch. The isolation plug is connected in series to the input path of the emergency parking branch; the output end of the electrically controlled solenoid valve is connected to the pre-control end of the dual-position pneumatic valve to drive the dual-position pneumatic valve to switch positions; the first air inlet of the dual-position pneumatic valve is connected to the parking branch, and the second air inlet of the dual-position pneumatic valve is connected to the pipeline between the pressure-holding check valve and the emergency air cylinder; the parking branch downstream of the isolation plug is connected to the emergency air cylinder through an air-filling pipeline with a pressure-holding check valve, and the pressure-holding check valve is directed towards the emergency air cylinder; The live contact side exhaust valve is connected in series downstream of the output port of the dual-position pneumatic control valve. Its side exhaust port is connected to the pipeline between the pressure-holding check valve and the emergency air cylinder, which is used to manually operate the valve to relieve parking braking in an emergency. The live contact end of the live contact side exhaust valve is connected to the driver's cab display terminal through a vehicle hardwire to provide feedback on the valve's position status.

[0023] The energized contact side exhaust damper has a built-in mechanical auxiliary electrical contact. The on / off state of the electrical contact corresponds one-to-one with the two working positions of the damper: the electrical contact is in the first on / off state when the working position is open, and switches to the second on / off state when the working position is closed. The output of the electrical contact is connected to the driver's cab display terminal via a hardwired connection. The driver can obtain the current working position status of each vehicle's damper in real time through the terminal without on-site confirmation.

[0024] In practical applications, this system is primarily used in locomotives and rolling stock equipped with spring-loaded parking cylinders. A spring-loaded parking cylinder refers to a type of brake cylinder where the braking force is output from a spring inside the cylinder; that is, the parking brake is a pure spring brake. When there is no pressurized air inside the parking cylinder, the spring force is output and presses against the friction pair to achieve parking braking; when pressurized air is introduced into the parking cylinder, the pressurized air overcomes the spring force, releasing the parking brake. This braking method is widely used in urban rail vehicles, EMUs, and locomotives.

[0025] Please see Figure 1 , Figure 1 This is a schematic diagram of the overall air circuit principle of the braking system of this application. The braking system of this embodiment mainly includes a brake control device 2, an air source distribution unit 3, an emergency parking release actuator 1, and an emergency air cylinder. The brake control device 2 and the air source distribution unit 3 are both installed under the vehicle, as is the emergency air cylinder, while the emergency parking release actuator 1 is installed under the seat on the vehicle. Each vehicle is equipped with a complete set of the above system.

[0026] The brake control device 2 is the core component for implementing service brake control and leakage monitoring in this application. The brake control device 2 includes a relay valve, an electronic control unit (hereinafter referred to as EBCU), a service brake pressure sensor, and a parking pressure sensor.

[0027] The relay valve is the core actuator in the brake control device 2 that realizes the brake cylinder pressure output. The relay valve is a pneumatic proportional control valve that works by controlling a larger output pressure using a smaller pre-control pressure signal. Specifically, the relay valve has a pre-control interface, an input end, and an output end. The input end connects to pressurized air from the air source distribution unit, and the pre-control interface connects to the pre-control pressure controlled by the EBCU. Internally, the relay valve proportionally adjusts the amount of pressurized air flowing from the input end to the output end according to the magnitude of the pre-control pressure, ultimately outputting the brake cylinder pressure corresponding to the pre-control pressure at the output end. Because of the relay valve, the EBCU only needs to control the smaller pre-control pressure to achieve precise regulation of the large flow of pressurized air in the brake cylinder, thereby reducing the power requirement of the solenoid valve and improving control accuracy.

[0028] The detection end of a commonly used brake pressure sensor is connected to the input line of a relay valve to collect the total air pressure value in real time. The signal output end of the sensor is electrically connected to the EBCU, transmitting the collected total air pressure signal to the EBCU. Based on the specific pressure value of this feedback signal, the EBCU displays fault information such as "brakes have been cut off" on the driver's cab screen.

[0029] The detection end of the parking pressure sensor is connected to the output end of the emergency parking relief actuator via a pressure tapping pipeline to collect the pressure value of the parking cylinder in real time. The signal output end of the sensor is electrically connected to the EBCU, transmitting the collected parking branch pressure signal to the EBCU. The pressure tapping point of the parking pressure sensor is located on the output pipe section of the emergency parking relief actuator, upstream of the parking cylinder, which accurately reflects the parking pressure value entering the parking cylinder.

[0030] The EBCU obtains pressure data from each car in the train formation through the train network. Specifically, the EBCU receives not only the total air pressure sensor and parking pressure sensor readings from its own car, but also the corresponding pressure readings from other cars in the same formation via train network communication. The EBCU combines its own total air pressure readings, parking pressure readings, and pressure data from other cars acquired through the network to make a comprehensive judgment: when the deviation between the total air pressure and parking pressure of a car exceeds the normal range, or when the pressure drop rate (pressure decrease per unit time) of a car is significantly greater than that of other cars in the formation, the EBCU identifies a pipeline leak in that car and locates the faulty car.

[0031] Air source distribution unit 3 is the component responsible for distributing and regulating the total air volume in this application. The input end of air source distribution unit 3 is connected to the main air duct (i.e., the train's main air duct, MR pipe), and the total air volume is compressed air with a certain pressure generated by the train's air compressor. The output end of air source distribution unit 3 branches into two lines: one is a braking line, which is connected to the input end of the relay valve in the braking control device 2, used to provide pressurized air for service braking; the other is a parking line, which is connected to the first air inlet of the emergency parking release actuator 1, used to provide pressurized air for releasing the parking brake.

[0032] Emergency parking mitigation unit 1 is the core component of this application for realizing leakage isolation and emergency parking mitigation functions. Its detailed internal gas path connections are as follows: Figure 2 As shown. The air outlet of the emergency parking relief execution unit 1 is connected to the parking cylinder. Inside, along the main air path, there are an isolation plug, a dual-position pneumatic control valve, and an exhaust plug with an electric contact side connected in series. It is also equipped with an electrically controlled relief solenoid valve for driving the dual-position pneumatic control valve to switch positions, and a pressure-holding check valve for unidirectionally charging the emergency air cylinder. All of the above valves are integrated on the same integrated air circuit board. The dashed box in the figure represents the coverage area of ​​the integrated air circuit board.

[0033] An isolation valve is connected in series to the input path of the emergency parking branch. The valve is a manually or remotely controlled pneumatic switch valve with both on and off operating states. In this embodiment, the isolation valve is used to switch to the off state when a pipeline leak is detected in a certain car, controlled by an operator or automatic control command. This cuts off the main air supply to the faulty car, preventing the leak from consuming the total air supply of the entire train and avoiding affecting the normal parking and braking release states of other cars. The isolation valve is located at the upstream position of the emergency parking release execution unit 1, meaning that the main air supply enters the emergency parking release execution unit 1 and first passes through the isolation valve before proceeding to other valves.

[0034] Combination Figure 2 The pneumatic control valve 12, a two-position three-way valve, has four ports: a first inlet 121, a second inlet 122, an outlet 123, and a pre-control terminal 124. This dual-position pneumatic control valve is a key component in this application for switching between normal and emergency operating conditions. The pneumatic control valve is a pneumatic valve controlled by a pressurized air signal; its operating state is determined by the presence of control pressure at its pre-control terminal. The dual-position pneumatic control valve has three ports: a first inlet, a second inlet, and an outlet. The first inlet connects to the parking branch, i.e., to the downstream pipeline of the isolation plug; the outlet connects to the parking cylinder; and the second inlet connects to the pipeline between the pressure-holding check valve and the emergency air cylinder. Under normal operating conditions, the dual-position pneumatic control valve is in the first position, with its first air inlet and outlet connected, while the second air inlet is closed. At this time, pressurized air from the parking branch can flow through the dual-position pneumatic control valve to the parking cylinder, maintaining sufficient pressure within the parking cylinder to overcome the spring force and maintain the released parking brake state. In emergency operating conditions, the dual-position pneumatic control valve switches to the second position, with its second air inlet and outlet connected, while the first air inlet is closed. At this time, the parking branch is cut off, and pressurized air from the emergency air cylinder can flow through the second air inlet to the outlet and then into the parking cylinder, thereby maintaining the released state of the parking cylinder.

[0035] The electrically controlled solenoid valve is used to drive the dual-position pneumatic control valve to switch positions. A solenoid valve is a valve controlled by an electrical signal; its operating state is determined by whether its solenoid coil is energized. The output of the electrically controlled solenoid valve is connected to the pre-control terminal of the dual-position pneumatic control valve. When the electrically controlled solenoid valve is energized, its output terminal outputs pressurized air to the pre-control terminal of the dual-position pneumatic control valve. This pressurized air actuates the valve core inside the dual-position pneumatic control valve, causing the valve to switch from the first position to the second position. When the electrically controlled solenoid valve is de-energized, its output terminal opens to the atmosphere, and the pressurized air at the pre-control terminal of the dual-position pneumatic control valve is discharged into the atmosphere through the electrically controlled solenoid valve. The dual-position pneumatic control valve returns to the first position under the action of the internal spring force. The control terminal of the electrically controlled solenoid valve extends to the control knob in the driver's cab electrical cabinet. The driver can control the energization or de-energization state of the electrically controlled solenoid valve by operating the control knob.

[0036] Combination Figure 2 It is known that the emergency air cylinder 4 is located downstream of the pressure-holding check valve 15, and the pressure-holding check valve 15 and the emergency air cylinder 4 are sequentially arranged in the main air passage downstream of the isolation plug 11. The emergency air cylinder is the energy storage component for emergency parking relief in this application. The emergency air cylinder is connected to the emergency parking relief execution unit 1 through an inflation pipeline. Specifically, the emergency parking branch downstream of the isolation plug is connected to the emergency air cylinder through an inflation pipeline with a pressure-holding check valve. The pressure-holding check valve is directed towards the emergency air cylinder, meaning that pressurized air can only flow from the emergency parking branch through the pressure-holding check valve to the emergency air cylinder, and cannot flow in the opposite direction. The function of the pressure-holding check valve is as follows: When the train's total air pressure is normal, the pressurized air in the parking branch line is supplied to the emergency air cylinder through the pressure-holding check valve, so that the emergency air cylinder stores compressed air with a certain pressure. When the pressure of the train's total air pressure drops due to pipeline leaks or other reasons, the pressure-holding check valve is in the closed state, preventing the pressurized air in the emergency air cylinder from flowing back into the main air pipe, thereby ensuring that the emergency air cylinder always maintains sufficient pressurized air for emergency relief. The second air inlet of the dual-position pneumatic control valve is connected to the pipeline between the pressure-holding check valve and the emergency air cylinder, that is, the air intake point of this second air inlet is located downstream of the pressure-holding check valve, closer to the emergency air cylinder. This setting ensures that in emergency conditions, when the total air pressure has dropped or even been lost, the pressurized air in the emergency air cylinder can still reach the second air inlet of the dual-position pneumatic control valve through this pipeline, and flow to the parking cylinder after the dual-position pneumatic control valve switches to the second position, realizing the emergency relief of parking braking.

[0037] Combination Figure 2It is known that the live contact side exhaust valve is normally in the conductive state, serving only as a conduit between the outlet of the dual-position pneumatic control valve and the parking cylinder. The side exhaust port is connected to the emergency air cylinder and is in the closed state with the live contact side exhaust valve conduit. When emergency release of the parking brake is required, as a mechanical redundancy, the live contact side exhaust valve can also be switched to the closed position. At this time, the air pressure from the outlet of the upstream dual-position pneumatic control valve is cut off inside the valve, while the side exhaust port and the downstream parking cylinder are connected inside the valve. In this way, the pressurized air from the emergency air cylinder is input into the parking cylinder through the side exhaust port and the outlet of the live contact side exhaust valve, which can also achieve emergency release of the parking brake.

[0038] The working principle of the braking system in this embodiment is as follows: Under normal operating conditions, the main air supply is divided into a braking branch and a parking branch by the air source distribution unit. The pressurized air in the parking branch flows directly to the parking cylinder through a dual-position pneumatic control valve (in the first position, with the first inlet and outlet connected), maintaining sufficient pressure within the parking cylinder to overcome the spring force and maintain the released parking brake. Simultaneously, pressurized air from the main air duct is supplied to the emergency air cylinder via an isolation plug and a pressure-holding check valve, storing pressurized air for later use. During this process, the EBCU acquires real-time readings from the main air pressure sensor and the parking pressure sensor, and obtains corresponding pressure data from each car in the train formation through the train network, continuously monitoring for pipeline leaks.

[0039] When a leak occurs in the train's piping due to impact from a foreign object or other reasons, the EBCU identifies and locates the leaking vehicle by comparing pressure data from all cars in the train set. Simultaneously, it outputs a warning signal to the driver's cab display terminal, prompting the driver to respond promptly. The driver manually operates the isolation valves of the faulty vehicle and adjacent downstream vehicles to switch to the cut-off state, disconnecting the main air duct of the faulty vehicle to prevent the leak from continuing to affect the overall air pressure of the entire train.

[0040] If leakage causes the total air pressure to drop to a point where the parking cylinder can no longer maintain its released state (i.e., the parking branch pressure falls below the release maintenance threshold), the parking brake is unexpectedly applied (spring force output). At this time, the driver can operate the control knob in the driver's cab electrical cabinet to energize the electronically controlled release solenoid valve. The solenoid valve outputs pressurized air to the pre-control terminal of the dual-position pneumatic valve, driving it to switch from the first position to the second position, thus opening the air passage between the emergency air cylinder and the parking cylinder. The pressurized air stored in the emergency air cylinder flows to the parking cylinder through the second inlet and outlet, causing the pressure in the parking cylinder to rise again, overcoming the spring force and releasing the parking brake. As a mechanical redundancy, the energized contact side exhaust valve can also be switched to the cut-off position. In this position, the valve cuts off the air pressure from the outlet of the upstream dual-position pneumatic control valve, while simultaneously connecting the side exhaust port to the downstream parking cylinder. This allows pressurized air from the emergency air cylinder to be input into the parking cylinder via the side exhaust port of the energized contact side exhaust valve and the valve outlet, thus achieving emergency release of the parking brake. Since this operation can be completed entirely on board, the driver does not need to manually operate the release device at the bogies, and no external rescue vehicle is required for air supply. The disabled train can rely on its own traction system to travel to a safe handling area.

[0041] In one embodiment of this application, the braking control device further includes an air charging solenoid valve, an air exhaust solenoid valve, and a pre-control pressure sensor; The air-filling solenoid valve, the air-exhausting solenoid valve, and the pre-controlled pressure sensor are all electrically connected to the electronic control unit. The air-filling solenoid valve and the air-exhausting solenoid valve are connected in series in the pre-control air path of the relay valve, and the detection end of the pre-control pressure sensor is connected to the pre-control interface of the relay valve. The electronic control unit calculates the target brake cylinder pressure based on the vehicle load, charges air into the relay valve pre-control interface through the air charging solenoid valve, collects the pre-control pressure through the pre-control pressure sensor and forms a closed-loop control, and outputs the corresponding pressure to the vehicle brake cylinder through the relay valve; and when the brake is released, the electronic control unit controls the exhaust solenoid valve to open to the atmosphere, so that the pressurized air in the brake cylinder is discharged through the relay valve.

[0042] Specifically, in actual operation, the braking control device 2 also includes an air charging solenoid valve, an air exhaust solenoid valve, and a pre-control pressure sensor. Both the air charging solenoid valve and the air exhaust solenoid valve are electrically controlled two-position three-way solenoid valves, that is, solenoid valves with two working positions and three interfaces. The switching of working positions is achieved by controlling the energization or de-energization of their solenoid coils by the EBCU.

[0043] The charging solenoid valve and the exhaust solenoid valve are connected in series in the pre-control air path of the relay valve. The pre-control air path refers to the air path through which the EBCU controls the output pressure of the relay valve. Specifically, the charging solenoid valve is connected in series between the pressurized air source and the pre-control interface of the relay valve. When the charging solenoid valve is energized, it opens the air path between the pressurized air source and the pre-control interface of the relay valve, allowing pressurized air to enter the pre-control interface of the relay valve; when the charging solenoid valve is de-energized, it cuts off this air path. The exhaust solenoid valve is connected in series between the pre-control interface of the relay valve and the atmosphere. When the exhaust solenoid valve is energized, it opens the passage between the pre-control interface of the relay valve and the atmosphere, allowing the pressurized air in the pre-control interface to be discharged into the atmosphere; when the exhaust solenoid valve is de-energized, it cuts off this passage.

[0044] The detection end of the pre-control pressure sensor is connected to the pre-control interface of the relay valve to collect the pressure value at the pre-control interface of the relay valve in real time. The signal output end of the sensor is electrically connected to the EBCU to transmit the collected pre-control pressure signal to the EBCU.

[0045] The EBCU calculates the target brake cylinder pressure based on the vehicle load. Specifically, the braking force required by the vehicle varies under different loads. The EBCU obtains the current load status of the vehicle by collecting values ​​from the air spring pressure sensor and calculates the target brake cylinder pressure value corresponding to each braking level under the current load according to a preset braking control algorithm. When the driver operates the corresponding braking level, the EBCU initiates the braking application control process: the EBCU charges air into the pre-control interface of the relay valve through the air charging solenoid valve, while simultaneously collecting the actual pressure value of the pre-control interface in real time through the pre-control pressure sensor and feeding it back to the EBCU. The EBCU compares the actual pre-control pressure value with the target pre-control pressure value and adjusts the conduction state of the air charging solenoid valve according to the deviation, so that the pre-control pressure accurately tracks the target value, forming a closed-loop control. The relay valve outputs the corresponding brake cylinder pressure to the vehicle brake cylinder proportionally according to the pre-control pressure value at its pre-control interface, realizing the application of service braking.

[0046] During braking control, the electronic control unit (ECU) collects the total air pressure of the brake branch at the relay valve input in real time through a common brake pressure sensor. This, combined with the closed-loop control results of the pre-controlled pressure, assists in determining the air supply status of the braking system. When the total air pressure falls below a set threshold, an insufficient air supply fault warning is generated and output to the driver's cab display terminal. Simultaneously, this total air pressure data serves as one of the two core bases for leakage monitoring, working together with parking pressure data and pressure data from other vehicles in the train to identify and locate leakage faults.

[0047] When brake release is required, the EBCU energizes the exhaust solenoid valve, opening the passage between the relay valve's pre-control interface and the atmosphere. This allows the pressurized air in the pre-control interface to be discharged, reducing the pre-control pressure. The relay valve reduces its output in response to the decrease in pre-control pressure. Simultaneously, the pressurized air in the brake cylinder flows through the internal passage of the relay valve to the exhaust solenoid valve and is discharged into the atmosphere, further reducing the brake cylinder pressure and releasing the brakes.

[0048] Through the cooperation of the aforementioned air-charging solenoid valve, air-draining solenoid valve, and pre-control pressure sensor, the EBCU achieves precise closed-loop control of commonly used braking pressure, ensuring that the brake cylinder pressure can quickly and accurately follow the driver's operating commands, thereby improving the response speed and accuracy of braking control.

[0049] In one embodiment of this application, the braking control device further includes a parking pressure acquisition board and matching internal and external wiring harnesses; The parking pressure sensor is connected to the signal input terminal of the electronic control unit via a parking pressure acquisition board, and the common brake pressure sensor is connected to the brake pressure acquisition channel of the brake control device.

[0050] In practical operation, the braking control device 2 also includes a parking pressure acquisition board and matching internal and external wiring harnesses. The parking pressure acquisition board is a dedicated hardware module in the EBCU used to process the parking pressure sensor signal. It internally contains signal conditioning circuits (such as filtering and amplification) and analog-to-digital conversion circuits to convert the analog signal output by the parking pressure sensor into a digital signal that the EBCU can process. The matching internal and external wiring harnesses include cables connecting the parking pressure sensor and the parking pressure acquisition board, as well as internal communication lines connecting the parking pressure acquisition board and the EBCU main processor.

[0051] The parking pressure sensor is connected to the signal input terminal of the EBCU via a parking pressure acquisition board. Specifically, the signal output terminal of the parking pressure sensor is connected to the input terminal of the parking pressure acquisition board via a wiring harness. After processing the signal, the parking pressure acquisition board transmits the digitized pressure value to the processor of the EBCU through an internal bus.

[0052] The total air pressure sensor for the service brake branch is connected to the brake pressure acquisition channel of the brake control device 2. This total air pressure acquisition channel is an existing hardware channel in the EBCU used to process the total air pressure sensor signal input to the service brake, and it already exists in the existing brake control device. This application makes full use of this existing hardware resource, without requiring any modification to the signal acquisition path of the total air pressure sensor connected to the brake control device 2.

[0053] The pressure tap of the parking pressure sensor is located on the output pipe of the emergency parking relief actuator. This location is downstream of the dual-position pneumatic control valve and upstream of the parking cylinder, accurately reflecting the actual parking pressure entering the parking cylinder, which is beneficial for subsequent leak monitoring and judgment. Furthermore, this pressure tap does not require modification of the internal pneumatic circuit board of the emergency parking relief actuator; only an additional pressure tap on the external pipeline is needed, reducing the difficulty and cost of modification.

[0054] In one embodiment of this application, the electronic control unit has a built-in leakage detection logic unit; The leakage judgment logic unit identifies leakage faults and locates the corresponding vehicles by comparing the parking pressure values ​​of each vehicle in the group with the total wind pressure value of the input common brake. Based on the identification results, it generates a warning signal and outputs it to the display terminal in the vehicle driver's cab.

[0055] Furthermore, the leakage judgment logic unit is configured to: receive the collected data of the total air pressure and parking pressure of the train in real time, and synchronously obtain the corresponding pressure data of the other cars in the train group through the train network; based on the second highest pressure of the same type in the train group, filter out abnormal cars whose pressure value deviation exceeds a preset threshold; compare the pressure drop time difference between the total air pressure and parking pressure of the abnormal cars, and combine the pressure drop rate per unit time to determine whether the leakage occurs in the pipeline between the air source distribution unit 3 and the braking control device 2, the parking branch, or the parking cylinder side pipeline; generate a corresponding level of warning signal according to the leakage location and pressure drop level and output it to the driver's cab display terminal.

[0056] Specifically, in practical applications, the leakage monitoring and emergency mitigation control logic framework of electronic control units is as follows: Figure 3 As shown. The leakage detection logic unit built into the electronic control unit is a program module implemented by software or firmware, used to perform leakage monitoring and fault location judgment; this unit completes comprehensive analysis by collecting the vehicle's own pressure signal and interactively grouping vehicle data to identify pipeline leaks and locate the faulty vehicle.

[0057] The leakage detection logic unit identifies leakage faults and locates the corresponding vehicles by comparing the parking pressure values ​​of each vehicle in the group with the total air pressure value of the input commonly used brakes, as well as the pressure deviation and pressure drop status. Specifically, corresponding to the signal transmission link in Figure 3, the leakage detection logic unit's judgment method includes the following steps: First, the EBCU obtains the parking branch pressure value of the train through the parking pressure sensor, obtains the total air pressure value of the train's common braking system through the total air pressure sensor, and obtains the parking pressure value and total air pressure value of other cars in the train formation through the train network.

[0058] Second, the leakage detection logic unit compares the parking pressure value of this vehicle with the parking pressure values ​​of other vehicles in the same train. Under normal operating conditions, the parking branch pressure of each vehicle in the same train should be basically the same (because the parking branches of each vehicle are supplied by the same main air source). If the parking pressure value of a certain vehicle is significantly lower than the benchmark value (the second highest pressure value), it is determined that the vehicle may have a parking branch leakage.

[0059] Third, the leakage detection logic unit compares the total air pressure value of this vehicle with the total air pressure values ​​of other vehicles in the same train. Under normal operating conditions, the total air pressure of each vehicle in the same train should be basically the same (at the same braking level). If the total air pressure value of a certain vehicle is significantly lower than the reference value (the second highest pressure value), it is determined that there may be a leakage upstream of the braking control device 2 of that vehicle.

[0060] Fourth, the leakage detection logic unit also monitors the rate of change of pressure values ​​of each vehicle over time (i.e., pressure drop rate). If the pressure drop rate of a certain vehicle is significantly faster than that of other vehicles in the group, even if the current pressure value is not yet significantly low, it can provide an early warning that the vehicle may be leaking, thereby achieving early detection of leakage.

[0061] Fifth, the leakage judgment logic unit integrates the above multiple judgment results, eliminates false alarms that may occur from a single judgment (such as sensor failure), and finally determines whether a pipeline leak has occurred and the specific vehicle involved in the leak.

[0062] When all cars in the train lose total air pressure synchronously without braking or major station transfers and there is no significant deviation between cars, the leakage judgment logic unit determines that the main air duct is leaking and outputs a total air leakage warning for the entire train. When the pressure value of a single car or a few cars deviates significantly from the average value of the train, it is determined that the corresponding car is leaking from a branch line, thus locating the faulty car.

[0063] Based on the identification results, the EBCU generates a warning signal and outputs it to the display terminal in the driver's cab. The display terminal can be a screen or alarm light in the driver's cab. The warning signal includes a notification of the leak, the vehicle number or location information of the faulty vehicle, and suggested handling measures (such as recommending isolation of the vehicle). Based on the information displayed on the terminal, the driver can promptly understand the specific details of the leak and take appropriate countermeasures.

[0064] In one embodiment of this application, the braking control device further includes an empty / load valve, an emergency solenoid valve, a forced release solenoid valve, and a forced release pneumatic control valve; The input end of the empty-load valve is connected to the air spring pressure, and the output end of the empty-load valve is connected to the emergency pre-control interface of the relay valve. The emergency solenoid valve is controlled by the electronic control unit. When it is turned on, the relay valve outputs emergency braking pressure to the brake cylinder. The forced release solenoid valve is controlled by the electronic control unit; the pre-control terminal of the forced release pneumatic control valve is connected to the output terminal of the forced release solenoid valve, and when it is turned on, it cuts off the upstream of the brake branch and turns the brake cylinder side passage to the atmosphere.

[0065] In actual operation, the braking control device 2 also includes an empty / load valve, an emergency solenoid valve, a forced release solenoid valve, and a forced release pneumatic control valve.

[0066] The air spring / air spring valve is a mechanical pressure regulating valve whose function is to automatically adjust the braking pressure according to the vehicle's load condition. The input of the air spring / air spring valve is connected to the air spring pressure. Air spring pressure refers to the internal pressure of the air spring, an important component of the vehicle's suspension system. Its internal pressure is positively correlated with the vehicle's load—the greater the load, the higher the air spring pressure. After the air spring pressure is connected to the input of the air spring / air spring valve, the internal mechanical mechanism of the air spring / air spring valve adjusts its output pressure according to the magnitude of the air spring pressure. The output of the air spring / air spring valve is connected to the emergency pre-control interface of the relay valve, providing a regulated pressure signal to the relay valve's emergency pre-control interface as the pre-control pressure for emergency braking. When the vehicle load is heavy, the air spring pressure is high, and the emergency pre-control pressure output by the air spring / air spring valve is correspondingly high, as is the emergency braking pressure output by the relay valve, thus providing greater braking force. Conversely, when the vehicle load is light, the air spring pressure is low, and the emergency pre-control pressure output by the air spring / air spring valve is low, as is the emergency braking pressure output by the relay valve, preventing excessive braking force from causing wheel slippage. The empty / load valve is a purely mechanical structure that does not rely on electrical control, thus offering advantages such as high reliability and fast response.

[0067] An emergency solenoid valve is connected in series in the pneumatic path between the output of the empty / loaded valve and the emergency pre-control interface of the relay valve. The control terminal is connected to the driver's cab via a hardwired connection. When emergency braking is applied (e.g., the emergency brake position on the driver's controller is triggered, or the train safety circuit is interrupted), the emergency solenoid valve is energized, opening the pneumatic path between the empty / loaded valve and the emergency pre-control interface of the relay valve. The emergency pre-control pressure output from the empty / loaded valve reaches the emergency pre-control interface of the relay valve via the emergency solenoid valve. The relay valve outputs the corresponding emergency braking pressure to the brake cylinder based on this emergency pre-control pressure, achieving emergency braking. The emergency braking pressure is typically higher than the maximum pressure of the service brake to ensure maximum braking force in emergencies. When the emergency solenoid valve is de-energized, it switches to the off state, simultaneously opening the passage between the emergency pre-control interface of the relay valve and the atmosphere, allowing the emergency pre-control pressure to be released. The brake cylinder pressure is then released via the relay valve, achieving emergency relief.

[0068] Forced release solenoid valves and forced release pneumatic valves are backup release methods used when normal braking fails to release the brakes. "Forced release" refers to the operation method where, when the brake control system malfunctions and the normal exhaust release function fails, pressurized air in the brake cylinder is forcibly expelled through a backup air circuit to release the brakes.

[0069] The forced release solenoid valve is controlled by the EBCU. When the driver issues a forced release command, the EBCU energizes the forced release solenoid valve, and the output of the forced release solenoid valve outputs pressurized air to the pre-control terminal of the forced release pneumatic control valve.

[0070] The pre-control terminal of the forced release air control valve is connected to the output terminal of the forced release solenoid valve. When the pre-control terminal of the forced release air control valve receives pressurized air from the forced release solenoid valve, the forced release air control valve switches its operating state: the valve switches to cut off the upstream of the brake branch (i.e., cut off the passage between the output terminal of the relay valve and the brake cylinder) and opens the passage on the brake cylinder side to the atmosphere (i.e., open the passage between the brake cylinder and the atmosphere). In this state, regardless of whether the relay valve continues to output pressure, the pressurized air in the brake cylinder is discharged into the atmosphere through the forced release air control valve, thereby achieving forced release of the brake cylinder. The forced release air control valve provides a backup release path in addition to the commonly used brake venting release, improving the safety of the braking system.

[0071] In one embodiment of this application, the air source distribution unit is equipped with a filter with a one-way valve, and the main air is divided into a braking branch and a parking branch after passing through the filter; A pressure reducing valve and a dual-pulse solenoid valve are connected in series on the parking branch. The outlet pressure of the pressure reducing valve is adjusted to be higher than that of a conventional pressure reducing valve, so as to cooperate with the parking pressure sensor to realize leakage detection in advance in the high-pressure range.

[0072] Specifically, in actual operation, the air source distribution unit 3 is equipped with a filter with a one-way valve. A filter is a component in a pneumatic system used to remove impurities (such as dust, moisture, oil mist, etc.) from compressed air. Its function is to remove solid particles, condensate, oil mist, and other contaminants that may be present in the total airflow, thereby protecting downstream pneumatic valves and actuators. The filter in this embodiment is a filter with a one-way valve. "With one-way valve" means that a one-way valve structure is integrated inside or outside the filter. The function of this one-way valve is to prevent a drop in air pressure in downstream components due to a decrease in total air pressure. Specifically, when the total air pressure is normal, compressed air flows through the one-way valve to the downstream pipeline of the filter; when the total air pressure drops due to leakage or other reasons, the one-way valve closes, preventing compressed air in the downstream pipeline from flowing back into the main air duct, thereby slowing down the rate of pressure drop in the downstream pipeline. After passing through the filter, the main airflow branches into a braking branch and a parking branch.

[0073] A pressure reducing valve and a dual-pulse solenoid valve are connected in series on the parking branch. The pressure reducing valve is a pressure regulating valve used to reduce the input pressure to the required output pressure and maintain stability. In this embodiment, the pressure reducing valve is installed on the parking branch, with its input end connected to the parking branch pressure output from the filter, and its output end connected to the dual-pulse solenoid valve. The pressure reducing valve's outlet pressure value can be set by adjusting the preload of its internal spring. In this embodiment, the outlet pressure of the pressure reducing valve is adjusted to be higher than that of a conventional pressure reducing valve. The outlet pressure of a conventional pressure reducing valve refers to the output pressure after pressure reduction by the pressure reducing valve, which in existing vehicles is generally slightly higher than the normal operating pressure required to maintain the parking cylinder's relaxed state. By increasing the outlet pressure of the pressure reducing valve in this embodiment, the parking branch operates at a higher pressure range. The advantage of this is that when a minor leak occurs in the parking branch, the higher operating pressure results in a more significant rate and magnitude of pressure drop, making it easier for the parking pressure sensor to detect. This achieves the goal of early detection of leaks in the high-pressure range, improving the sensitivity of leak detection and facilitating early warning and countermeasures. The dual-pulse solenoid valve is an electrically controlled valve installed on the parking branch. Its key feature is that it has two independent solenoid coils, which control the application and release of the parking brake separately. The output of the dual-pulse solenoid valve is connected to the first air inlet of the emergency parking release actuator 1. When the parking brake needs to be released, the release solenoid of the dual-pulse solenoid valve is energized via a button in the driver's cab, allowing pressurized air from the parking branch to enter the emergency parking release actuator 1 through the dual-pulse solenoid valve and then reach the parking cylinder. When the parking brake needs to be applied, the application solenoid of the dual-pulse solenoid valve is energized via a button in the driver's cab, allowing pressurized air in the parking cylinder to be discharged into the atmosphere through the exhaust port of the dual-pulse solenoid valve.

[0074] In one embodiment of this application, the emergency parking relief execution unit adopts an integrated pneumatic circuit board structure, and the isolation plug, the dual-position pneumatic control valve, the electrically controlled relief solenoid valve, and the energized contact side exhaust plug are all plate-type valves and are integrated and installed on the integrated pneumatic circuit board; The emergency parking mitigation unit is installed inside the passenger compartment of the vehicle, and each vehicle is equipped with one.

[0075] Specifically, in practical operation, the emergency parking mitigation unit 1 adopts an integrated pneumatic circuit board structure. An integrated pneumatic circuit board refers to a structure in which multiple pneumatic valves are integrated and mounted on the same base plate. This base plate has internally machined pneumatic channels corresponding to the interfaces of each valve, allowing the valves to communicate with each other through these internal channels, eliminating the need for extensive external piping. The integrated pneumatic circuit board structure has the following advantages: firstly, it reduces the number of piping connection points, lowering the risk of leakage; secondly, it has a compact structure, saving installation space; and thirdly, it facilitates mass production and maintenance / replacement.

[0076] The isolation plug, dual-position pneumatic control valve, electrically controlled solenoid valve, and energized contact side exhaust plug are all plate-type valves integrated into the integrated air manifold. Plate-type valves refer to valves with a flat mounting surface and interfaces directly mounted on it. These valves can be directly installed on the corresponding interfaces of the integrated air manifold, secured with bolts, and sealed with O-rings between the mounting surfaces. The positions of each plate-type valve on the integrated air manifold are optimized to minimize the internal air passages between valves, reducing pressure loss.

[0077] The emergency parking mitigation unit 1 is installed inside the passenger compartment, specifically under the seats. Compared to installing it under the vehicle, installing the emergency parking mitigation unit 1 inside the passenger compartment offers the following advantages: First, the passenger compartment environment is relatively clean and dry, which helps extend the service life of the valves; second, the passenger compartment facilitates maintenance personnel's inspection and operation; third, when manual operation of the isolation valve and the exhaust valve on the side with live contacts is required, operators do not need to get off the vehicle, improving operational safety and convenience. Each car is equipped with one set of emergency parking mitigation unit 1, meaning each car has an independent set of emergency parking mitigation unit 1. Each car's emergency parking mitigation unit 1 can be independently controlled and is redundantly operated both electrically and manually, thus achieving single-car isolation and single-car emergency mitigation functions.

[0078] In one embodiment of this application, the control terminal of the electrically controlled solenoid valve extends to the control knob of the driver's cab electrical cabinet. By operating the control knob, the electrically controlled solenoid valve is energized or de-energized, thereby driving the dual-position pneumatic control valve to switch the conduction position.

[0079] In practical operation, the control terminal of the electrically controlled solenoid valve extends to the control knob of the driver's cab electrical cabinet. The control knob is an operating element located on the panel of the driver's cab electrical cabinet, which the driver can rotate or press to issue control commands. The control knob contains electrical contacts; when the knob is operated to a specific position, the contacts close or open, thereby controlling the power supply status of the electrically controlled solenoid valve.

[0080] The driver operates a control knob to energize or de-energize the electrically controlled solenoid valve, which in turn switches the dual-position pneumatic control valve between its operating positions. Specifically, when the driver turns the control knob to the "emergency release" position, the power supply circuit of the electrically controlled solenoid valve is connected, energizing the solenoid valve. Its output terminal outputs pressurized air to the pre-control terminal of the dual-position pneumatic control valve, which switches from the first position to the second position. The emergency air cylinder and the parking cylinder are connected, realizing the emergency release of the parking brake.

[0081] The control knob can be set to single-car control mode or whole-train control mode. In single-car control mode, operating the control knob only controls the electrically controlled release solenoid valve of the car (i.e., the car where the driver is located), realizing emergency release of a single car. In whole-train control mode, operating the control knob simultaneously controls the electrically controlled release solenoid valves of all cars in the train, realizing emergency release of the entire train. The control mode can be set via another selection switch.

[0082] Since the control end of the electronically controlled solenoid valve has been extended to the driver's cab, the driver can complete the emergency relief operation without leaving the cab, which greatly improves the efficiency and safety of emergency response.

[0083] In one embodiment of this application, the emergency parking relief execution unit is further provided with a live contact side exhaust valve. The live contact side exhaust valve is connected in series to the pipeline on the parking cylinder side. The operating end of the side exhaust valve is located on the passenger compartment side of the vehicle, serving as a mechanical redundancy means for emergency parking relief.

[0084] In practical operation, the emergency parking relief actuator 1 is also equipped with a live-contact side exhaust valve. Normally, the live-contact side exhaust valve is in the conductive state, serving only as a conduit between the outlet of the dual-position pneumatic control valve and the parking cylinder. The side exhaust port is connected to the emergency air cylinder, but the conduit between the live-contact side exhaust valve and the side exhaust valve is in the closed state. When emergency parking brake relief is required, as a mechanical redundancy, the live-contact side exhaust valve can be switched to the closed position. At this time, the valve cuts off the air pressure from the outlet of the upstream dual-position pneumatic control valve, while simultaneously connecting the side exhaust port to the downstream parking cylinder. This allows the pressurized air from the emergency air cylinder to enter the parking cylinder through the side exhaust port and the valve outlet, thus achieving emergency parking brake relief. The live-contact side exhaust valve is connected in series to the pipeline on the parking cylinder side, specifically in the pipeline between the outlet of the dual-position pneumatic control valve and the parking cylinder. The operating end of the energized contact side exhaust damper is located on the passenger compartment side of the vehicle, meaning that the operator can manually operate the damper from inside the passenger compartment without having to go outside the vehicle.

[0085] The energized contact side exhaust plug serves as a mechanical backup for emergency parking relief. Together with the electrically controlled relief solenoid valve, it forms a dual-redundant emergency parking relief mechanism. Even if the electrical system fails completely, operators can still manually apply emergency parking relief, further improving the system's reliability and safety.

[0086] In one embodiment of this application, the dual-position pneumatic control valve is a two-position three-way pneumatic control valve; the two-position three-way means that the valve has two working positions and three interfaces (a first air inlet, a second air inlet, and an air outlet), and the switching of its working positions is controlled by the pressure signal of the pre-control end.

[0087] Under normal operating conditions, the electrically controlled solenoid valve is de-energized, and there is no pressurized air input to the pre-control end of the dual-position pneumatic control valve. The dual-position pneumatic control valve is in its first position under the action of its internal return spring. In the first position, the first air inlet and outlet are connected, while the second air inlet is blocked. At this time, pressurized air from the parking branch flows through the first air inlet to the outlet, and then through the side exhaust plug (in the open state) to the parking cylinder, maintaining the parking cylinder's release state.

[0088] In emergency situations, the electrically controlled solenoid valve is energized, and the pre-control terminal of the dual-position pneumatic control valve receives the pressurized air output from the solenoid valve. This pressurized air pushes the valve core inside the dual-position pneumatic control valve to overcome the force of the return spring, causing the dual-position pneumatic control valve to switch to the second position. In the second position, the second air inlet and outlet are connected, while the first air inlet is closed. At this time, pressurized air from the emergency air cylinder (via the pipeline between the pressure-holding check valve and the emergency air cylinder) flows from the second air inlet to the outlet, and then flows through the side exhaust plug (in the open state) to the parking cylinder, maintaining the released state of the parking cylinder. Simultaneously, because the first air inlet is closed, the parking branch is cut off; even if there is still leakage in the parking branch, it will not affect the pressure of the parking cylinder.

[0089] The dual-position pneumatic control valve achieves seamless switching between the normal air supply source (parking branch) and the emergency air supply source (emergency air cylinder). During the switching process, the air outlet remains connected to at least one air inlet, ensuring the continuity of air supply to the parking cylinder and preventing pressure interruptions that could lead to accidental application of the parking brake.

[0090] Based on the braking system described in the above embodiments, the working principle of this application will be fully explained below; those skilled in the art will understand that this explanation does not limit this application in any way.

[0091] Under normal operating conditions, the main air supply enters through the input terminal of the air source distribution unit 3. It first passes through a filter with a one-way valve to remove impurities, and then splits into two branches: a braking branch and a parking branch. The braking branch connects to the relay valve input terminal of the braking control device 2 to provide pressurized air for the service brake. The parking branch passes through a pressure reducing valve for pressure adjustment and a dual-pulse solenoid valve for control before entering the first air inlet of the emergency parking release actuator 1. Inside the emergency parking release actuator 1, the pressurized air from the parking branch passes through a dual-position pneumatic control valve (first position, with the first air inlet and outlet connected) and a side exhaust plug (conducting state) to reach the parking cylinder, maintaining sufficient pressure within the parking cylinder to overcome the spring force and maintain the released parking brake state. Simultaneously, the pressurized air from the emergency parking branch is supplied to the emergency air cylinder via a pressure-holding one-way valve, allowing the emergency air cylinder to store pressurized air for later use.

[0092] During the above process, the EBCU of the braking control device 2 receives the total air pressure in real time from the total air pressure sensor, collects the parking branch pressure in real time from the parking pressure sensor, and obtains the corresponding pressure data of each car in the train formation through the train network. The leakage judgment logic unit built into the EBCU analyzes and compares these data to continuously monitor the pipeline leakage status.

[0093] When a leak occurs in the train's piping, the EBCU's leak detection logic unit identifies and locates the leaking vehicle by comparing the pressure deviation and pressure drop status of each car in the train set, and generates a warning signal that is output to the display terminal in the driver's cab. Based on the warning, the driver manually operates the isolation valves of the faulty vehicle and its downstream vehicles to switch to the cut-off state, cutting off the main air supply to the faulty vehicle and achieving single-vehicle leak isolation.

[0094] When leakage causes a continuous drop in total air pressure and the parking branch pressure falls below the release and maintenance threshold, the parking brake is accidentally applied due to spring force. At this time, the driver can operate the control knob in the driver's cab electrical cabinet to energize the electrically controlled release solenoid valve. The solenoid valve outputs pressurized air to the pre-control terminal of the dual-position pneumatic control valve, driving it to switch from the first position to the second position. In the second position, the air passages between the emergency air cylinder and the parking cylinder are connected. The pressurized air stored in the emergency air cylinder (unaffected by the drop in total air pressure due to the pressure-holding check valve) flows to the parking cylinder through the second air inlet, outlet, and side exhaust plug, causing the pressure in the parking cylinder to rise again, overcoming the spring force and releasing the parking brake. Afterward, the disabled train can rely on its own traction system to travel to a safe disposal area.

[0095] In the extreme case of electronic relief failure, the operator can manually operate the live contact side exhaust valve to the cut-off position inside the vehicle's passenger compartment. At this time, the valve will cut off the air pressure from the outlet of the upstream dual-position pneumatic valve. At the same time, the valve will connect the side exhaust port and the downstream parking cylinder. In this way, the pressurized air of the emergency air cylinder will be input into the parking cylinder through the side exhaust port of the live contact side exhaust valve and the valve outlet, which can also realize the emergency relief of the parking brake. The beneficial technical effects of this application are as follows: By adding a parking pressure sensor to the braking control device and comparing it with the total air pressure sensor in the braking control device and the train network formation pressure data, real-time monitoring of pipeline leakage and accurate location of faulty vehicles are achieved, solving the problem that the existing system cannot provide early warning of leakage faults; by setting an isolation plug connected in series with the parking branch, the total air path of the faulty vehicle can be cut off in time when leakage occurs, preventing the leakage from continuously affecting the total air pressure of the entire vehicle; by setting a dual-position pneumatic control valve and an emergency air cylinder, and configuring a pressure-holding one-way valve, the emergency air cylinder can still maintain a pressure-storing state when the total air pressure drops. It can remotely control the emergency parking brake of the entire train or a single car through the electrically controlled solenoid valve in the driver's cab, and manually mechanically release the parking brake through the exhaust plug on the live contact side. The dual redundancy design ensures that the parking brake can still be quickly released after the total air pressure is lost, so that the faulty train can be towed to a safe handling area without the need for external rescue vehicles, which greatly improves the efficiency of handling leakage faults and the safety of train operation.

[0096] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In the description of this specification, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the embodiments in this specification. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0097] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above descriptions are merely specific embodiments of this application and are not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A braking system with leakage monitoring and emergency parking relief functions, applied to locomotives and rolling stock equipped with spring-loaded parking cylinders, characterized in that, The system includes a braking control device, an air supply distribution unit, an emergency parking relief execution unit, and an emergency air cylinder; The braking control device includes a relay valve, an electronic control unit, a common brake pressure sensor, and a parking pressure sensor. The detection end of the service brake pressure sensor is connected to the input pipeline of the relay valve, and the detection end of the parking pressure sensor is connected to the output pipeline of the emergency parking relief actuator via the pressure tapping pipeline. The signal output ends of both the service brake pressure sensor and the parking pressure sensor are electrically connected to the electronic control unit. The electronic control unit obtains the pressure data of each car in the train formation through the train network, and combines the detection values ​​of the service brake pressure sensor and the parking pressure sensor to identify pipeline leaks and locate the faulty car. The air source distribution unit is connected to the main air supply and splits into a braking branch and a parking branch. The braking branch is connected to the input terminal of the relay valve, and the parking branch is connected to the first air inlet of the emergency parking relief execution unit. The emergency parking relief execution unit has an air outlet connected to the parking cylinder and is internally equipped with an isolation plug, a dual-position pneumatic valve, an electrically controlled relief solenoid valve that drives the switching position, and an exhaust plug with live contacts connected in series with the input path of the emergency parking branch. The isolation plug is connected in series to the input path of the emergency parking branch; the output end of the electrically controlled solenoid valve is connected to the pre-control end of the dual-position pneumatic valve to drive the dual-position pneumatic valve to switch positions; the first air inlet of the dual-position pneumatic valve is connected to the parking branch, and the second air inlet of the dual-position pneumatic valve is connected to the pipeline between the pressure-holding check valve and the emergency air cylinder; the emergency parking branch downstream of the isolation plug is connected to the emergency air cylinder through an air-filling pipeline with a pressure-holding check valve, and the pressure-holding check valve is directed towards the emergency air cylinder; The live contact side exhaust valve is connected in series downstream of the output port of the dual-position pneumatic control valve. Its side exhaust port is connected to the pipeline between the pressure-holding check valve and the emergency air cylinder, which is used to manually operate the valve to relieve parking braking in an emergency. The live contact end of the live contact side exhaust valve is connected to the driver's cab display terminal through a vehicle hardwire to provide feedback on the valve's position status.

2. The braking system with leakage monitoring and emergency parking relief functions according to claim 1, characterized in that, The braking control device also includes an air charging solenoid valve, an air exhaust solenoid valve, and a pre-control pressure sensor. The air-filling solenoid valve, the air-exhausting solenoid valve, and the pre-controlled pressure sensor are all electrically connected to the electronic control unit. The air-filling solenoid valve and the air-exhausting solenoid valve are connected in series in the pre-control air path of the relay valve, and the detection end of the pre-control pressure sensor is connected to the pre-control interface of the relay valve. The electronic control unit calculates the target brake cylinder pressure based on the vehicle load, charges air into the relay valve pre-control interface through the air charging solenoid valve, collects the pre-control pressure through the pre-control pressure sensor and forms a closed-loop control, and outputs the corresponding pressure to the vehicle brake cylinder through the relay valve; and when the brake is released, the electronic control unit controls the exhaust solenoid valve to open to the atmosphere, so that the pressurized air in the brake cylinder is discharged through the relay valve.

3. The braking system with leakage monitoring and emergency parking relief functions according to claim 2, characterized in that, The braking control device also includes a parking pressure acquisition board and matching internal and external wiring harnesses; The parking pressure sensor is connected to the signal input terminal of the electronic control unit via a parking pressure acquisition board, and the common brake pressure sensor is connected to the brake pressure acquisition channel of the brake control device.

4. The braking system with leakage monitoring and emergency parking relief functions according to claim 3, characterized in that, The electronic control unit has a built-in leakage detection logic unit; The leakage judgment logic unit identifies leakage faults and locates the corresponding vehicles by comparing the parking pressure values ​​of each vehicle in the group with the total air pressure value and the pressure drop status; based on the identification results, it generates a warning signal and outputs it to the display terminal in the vehicle driver's cab.

5. The braking system with leakage monitoring and emergency parking relief functions according to claim 4, characterized in that, The leakage detection logic unit is configured as follows: It receives real-time data on the total air pressure and parking pressure of the train and synchronously obtains the corresponding pressure data of the other cars in the train formation through the train network. Based on the second highest pressure value of the same type of group, abnormal vehicles whose pressure value deviation exceeds the preset threshold are screened out. By comparing the pressure drop sequence differences between the total air pressure and the parking pressure of the abnormal vehicle, and combining the pressure drop rate per unit time, it can be determined whether the leakage occurred in the main air branch, the parking branch, or the parking cylinder side pipeline. Based on the location of the leak and the pressure drop level, a corresponding warning signal is generated and output to the display terminal in the driver's cab.

6. The braking system with leakage monitoring and emergency parking relief functions according to claim 2, characterized in that, The braking control device also includes an empty / load valve, an emergency solenoid valve, a forced release solenoid valve, and a forced release pneumatic valve. The input end of the empty-load valve is connected to the air spring pressure, and the output end of the empty-load valve is connected to the emergency pre-control interface of the relay valve. The emergency solenoid valve is controlled by the electronic control unit. When it is turned on, the relay valve outputs emergency braking pressure to the brake cylinder. The forced release solenoid valve is controlled by the electronic control unit; the pre-control terminal of the forced release pneumatic control valve is connected to the output terminal of the forced release solenoid valve, and when it is turned on, it cuts off the upstream of the brake branch and turns the brake cylinder side passage to the atmosphere.

7. The braking system with leakage monitoring and emergency parking relief functions according to claim 1, characterized in that, The air source distribution unit is equipped with a filter with a one-way valve. After the main air passes through the filter, it is divided into a braking branch and a parking branch. A pressure reducing valve and a dual-pulse solenoid valve are connected in series on the parking branch. The outlet pressure of the pressure reducing valve is adjusted to be higher than that of a conventional pressure reducing valve, so as to cooperate with the parking pressure sensor to realize leakage detection in advance in the high-pressure range.

8. The braking system with leakage monitoring and emergency parking relief functions according to claim 1, characterized in that, The emergency parking relief execution unit adopts an integrated air circuit board structure. The isolation plug, the dual-position air control valve, the electrically controlled relief solenoid valve, and the energized contact side exhaust plug are all plate-type valves and are integrated and installed on the integrated air circuit board. The emergency parking mitigation unit is installed inside the passenger compartment of the vehicle, and each vehicle is equipped with one.

9. The braking system with leakage monitoring and emergency parking relief functions according to claim 1, characterized in that, The control terminal of the electrically controlled solenoid valve extends to the control knob of the driver's cab electrical cabinet. By operating the control knob, the electrically controlled solenoid valve is energized or de-energized, thereby driving the dual-position pneumatic control valve to switch the operating position.

10. The braking system with leakage monitoring and emergency parking relief functions according to claim 1, characterized in that, The dual-position pneumatic control valve is a two-position three-way pneumatic control valve; Under normal operating conditions, the solenoid valve loses power and the dual-position pneumatic valve is in the first position, with the first air inlet and outlet connected and the second air inlet cut off. In emergency situations, the electrically controlled solenoid valve is energized, and the dual-position pneumatic valve switches to the second position, connecting the second air inlet and outlet while cutting off the first air inlet.

11. The braking system with leakage monitoring and emergency parking relief functions according to claim 1, characterized in that, The exhaust plug door on the side with live contacts; Under normal operating conditions, the live contact side exhaust plug serves as a channel for the air path, connecting the upstream and downstream air paths; under emergency operating conditions, the live contact side exhaust plug cuts off the upstream air path and connects the downstream and side exhaust vents.

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