Pressure regulating device of train emergency braking system

Abstract

The invention discloses a pressure regulating device for a train emergency braking system. The pressure regulating device comprises an empty and load valve, a plug-in type multi-proportion integrated pressure reducing valve, a four-position five-way electromagnetic valve, a pressure sensor, an emergency electromagnetic valve, a relay valve and the like. The rear end of an empty and load valve is matched with a plug-in type multi-proportion integrated pressure reducing valve to conduct specific proportion pressure reduction on VL pressure, a pressure sensor is combined to obtain a pressure value, finally, an EBCU controls a four-position five-way electromagnetic valve to select and output more accurate emergency braking pre-control pressure Pi, flow amplification is conducted through a relay valve, and the emergency braking pre-control pressure Pi is obtained. Accurate adjustment of emergency braking pressure is achieved. According to the device, the optimal brake pressure output selection is provided under the emergency condition, so that the device can more flexibly adapt to complex and changeable operation conditions, unnecessary wheel abrasion and slipping phenomena are avoided, and the response speed and reliability of emergency braking are improved.

Description

Technical Field

[0001] The invention relates to the technical field of rail transit braking, in particular to a pressure regulating device for a train emergency braking system. Background Art

[0002] Emergency braking is a braking method used to decelerate the train quickly and achieve an emergency stop in the shortest distance in an emergency situation. Domestic and foreign EMUs are divided into emergency braking EB (Emergency Brake) and emergency braking UB (Urgent Brake). Emergency braking EB is an emergency braking implemented under normal conditions of the braking control system equipment. Braking control is implemented according to the speed mode curve control method. Air-electric composite braking is used. When electric braking is not available, pure air braking controlled by a microcomputer is used. It is mainly used for alarm conditions triggered when the train is normal. Emergency braking UB is an emergency braking implemented when the emergency braking safety loop loses power. It uses pure air braking. It is mainly used for braking triggered when the train equipment is abnormal or in an emergency. Relief is not allowed before the train stops completely. The present invention will be explained with respect to emergency braking UB.

[0003] When the train performs emergency braking UB, the empty and loaded vehicle valve outputs the corresponding VL pressure to the relay valve for flow amplification according to the input empty spring pressure AS (i.e. vehicle load signal), so as to realize the function that the emergency braking pressure changes with the vehicle load. Figure 1 The Harmony EMU shown is Figure 2 The schematic diagram of the air circuit of the emergency brake system of the Fuxing EMU is shown in the figure. The Harmony EMU uses a single-stage empty and loaded valve, and its AS-AL curve diagram is shown in the figure. Figure 3 As shown; Fuxing EMU adopts a double-stage empty and loaded vehicle valve, and its AS-AL curve diagram is shown in Figure 4 As shown. Figure 3 and Figure 4 It can be seen that the emergency brake UB of Fuxing EMU has a speed graded control function compared to Harmony EMU. The EBCU will control the power-on and power-off of the high- and low-pressure switching solenoid valves of the empty and loaded vehicle valves at different speed levels. When the train is at low speed, the solenoid valve loses power and outputs a high-voltage curve; when the train is at high speed, the solenoid valve is energized and outputs a low-voltage curve.

[0004] The single-stage empty and loaded valve can change the VL pressure and adjustment ratio (slope) by rotating the adjustment bolt. The double-stage empty and loaded valve is adjusted for a specific ratio and the ratio cannot be adjusted. The VL pressure can only be adjusted by the screw. When the train speed changes and the vehicle weight is constant, the VL pressure output by the empty and loaded valve cannot be determined to be the optimal braking pressure. The reasons are as follows: For the single-stage empty and loaded valve, since it can only output braking pressure according to the vehicle weight and cannot be calculated according to the vehicle speed, there are certain limitations; for the double-stage empty and loaded valve, compared with the single-stage empty and loaded valve, it can output two pressure curves of high and low pressure according to the vehicle speed, but the output VL pressure is limited in refinement and can only be adjusted according to the set AS-VL curve, and more accurate pressure regulation cannot be achieved. Moreover, it is not convenient to adjust the output characteristics of the empty and loaded valve after loading, which has certain limitations. Summary of the invention

[0005] In response to the problems existing in the prior art, the present invention provides a device that provides optimal brake pressure output selection in emergency situations, so as to more flexibly adapt to complex and changeable operating conditions, avoid unnecessary wheel wear and slippage, and improve the response speed and reliability of emergency braking, thereby realizing a train emergency brake system pressure regulating device.

[0006] The purpose of the present invention is achieved through the following technical solutions.

[0007] A pressure regulating device for a train emergency brake system includes: an empty and loaded vehicle valve, a plug-in multi-proportional integrated pressure reducing valve, a four-position five-way solenoid valve, a pressure sensor, an emergency solenoid valve, and a relay valve. The plug-in multi-proportional integrated pressure reducing valve is used at the rear end of the empty and loaded vehicle valve to reduce the VL pressure by a specific proportion, and the pressure value is obtained by combining with the pressure sensor. Finally, the EBCU controls the four-position five-way solenoid valve to select and output a more accurate emergency brake pre-control pressure P. i , and then the flow is amplified through the relay valve to achieve precise adjustment of the emergency brake pressure.

[0008] The empty and loaded vehicle valve outputs a corresponding pre-control pressure VL in proportion to the total air input and the empty spring pressure AS value. The empty and loaded vehicle valve has the empty vehicle guarantee and empty and loaded vehicle adjustment functions and has an empty vehicle guarantee output pressure. The empty and loaded vehicle valve outputs two types of high and low pressure curves by adjusting the gain and loss of electricity of the emergency switching solenoid valve.

[0009] Optionally, the total air is provided by the SR (Supply Reservoir) air cylinder, and the air spring pressure refers to the AS (Air Spring) pressure.

[0010] The plug-in multi-proportional integrated pressure reducing valve is composed of four groups of proportional pressure reducing valves with different diaphragm areas, and outputs four pre-controlled pressures Pi (i=1, 2, 3, 4) after reducing the input VL pressure in different proportions.

[0011] The four groups of proportional pressure reducing valves with different diaphragm plate areas have different ratios of effective diaphragm plate areas between the inlet end and the outlet end of the valve stem of each group, so the pressure reducing ratios are different.

[0012] Preferably, VL represents the inlet pressure, Pi represents the outlet pressure, S1 represents the inlet effective area, and S2 represents the outlet effective area. When friction is ignored and the valve stem is under force balance, the pressure reduction ratio VL:Pi=S2:S1.

[0013] The pressure sensor is connected to the EBCU and is used to monitor the P1, P2, P3, and P4 pressures outputted from the rear end of the plug-in multi-proportional integrated pressure reducing valve.

[0014] Preferably, the pressure sensor transmits the collected pressure signal to the EBCU, and the EBCU obtains the optimal brake pressure according to the current vehicle speed matching, and outputs it to the emergency solenoid valve through the four-position five-way solenoid valve.

[0015] The four-position five-way solenoid valve has the main function of switching between four working positions, controlling the flow of four decompressed gases from the input end to the output end, and selecting to output a specific proportion of the decompressed pressure (one of P1, P2, P3, and P4).

[0016] The emergency solenoid valve is turned on when it loses power under the emergency braking UB condition, and inputs the Pi pressure output by the four-position five-way solenoid valve into the relay valve.

[0017] The relay valve is used to amplify the flow of the emergency brake pre-control pressure AC2 (ie Pi).

[0018] Compared with the prior art, the advantages of the present invention are as follows: With the continuous commissioning of EMU trains, ensuring the reliability and safety of trains when running at high speeds has always been a concern. In particular, when a train encounters an unexpected danger or equipment failure, it is necessary to ensure that the train can stop quickly and safely when running at high speed. When a train is running at high speed, if the braking force is too large, it may cause the wheels to slip, and in certain heavy load or high-speed conditions, insufficient braking force may affect the braking effect and safety. Therefore, EMU trains need a device that can provide the best brake pressure output selection in an emergency, so as to more flexibly adapt to complex and changeable operating conditions, avoid unnecessary wheel wear and slippage, and improve the response speed and reliability of emergency braking.

[0019] The present invention provides a pressure regulating device for a train emergency brake system with proportional output regulation, which can output corresponding Pi pressures at different vehicle weights and speed levels, that is, provide more accurate braking pressures to ensure emergency braking of the train, avoid safety risks caused by insufficient braking force, extended braking distance, and increased maintenance costs caused by brake pad wear. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is the gas circuit schematic diagram of the emergency brake system of the Harmony train;

[0021] Figure 2 This is the gas circuit schematic diagram of the emergency brake system of Fuxing train;

[0022] Figure 3 It is the single-stage empty and loaded vehicle valve AS-VL curve;

[0023] Figure 4 It is the AS-VL curve of the double-stage empty and loaded vehicle valve;

[0024] Figure 5 It is a schematic diagram of the structure of the present invention;

[0025] Figure 6 The AS-VL curves after four specific ratios of decompression in the present invention (taking the two-stage empty and loaded vehicle valve as an example);

[0026] Figure 7 This is the gas circuit schematic diagram of the new train emergency brake system;

[0027] Figure 8 It is a plug-in multi-proportional integrated pressure reducing valve;

[0028] Fig. 9 This is a schematic diagram of a certain proportional pressure reducing valve;

[0029] Fig.10 It is the graphic symbol of a four-position five-way solenoid valve;

[0030] Fig.11 This is the air path flow direction of the emergency brake UB of the present invention (taking P1 pressure as an example). DETAILED DESCRIPTION

[0031] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0032] Example

[0033] The brake pressure required by the train during emergency braking UB is provided by the empty-load valve. The current design of the single-stage and double-stage empty-load valves has certain limitations. The single-stage empty-load valve can only adjust the brake pressure according to the weight of the vehicle, and cannot be adjusted dynamically according to the speed of the vehicle, resulting in poor accuracy and adaptability of the output pressure. Although the double-stage empty-load valve can output two pressure curves according to the speed of the vehicle, its adjustment range and accuracy are limited. It can only rely on the preset AS-VL curve and cannot achieve more accurate pressure regulation.

[0034] In response to the above problems, the present invention proposes a new type of train emergency braking system pressure regulating device, taking a two-stage empty and loaded vehicle valve as an example, providing a plug-in multi-proportional integrated pressure reducing valve with convenient adjustment of output characteristics, aiming to output more types of braking pressures to ensure that the train braking process is safe, smooth and fast.

[0035] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the embodiments of the present application are further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0036] See also Figure 5 , which is a schematic diagram of the technical solution of a new type of train emergency brake system pressure regulating device provided in an embodiment of the present invention.

[0037] The pressure regulating device includes an empty and loaded vehicle valve, a plug-in multi-proportional integrated pressure reducing valve, a four-position five-way solenoid valve, a pressure sensor, an emergency solenoid valve, and a relay valve. Under the emergency braking UB condition of the EMU, the empty and loaded vehicle valve adjusts the output of the corresponding control pressure VL according to the vehicle weight under the action of the total air and empty spring pressure AS; the plug-in multi-proportional integrated pressure reducing valve reduces the pressure of VL by a specific proportion and outputs 4 pre-control pressures P of different proportions. i (i=1,2,3,4), the diaphragms with different pressure reduction ratios (different diaphragm areas) can be replaced to adjust the output pressure Pi, and the pressure value is obtained through the pressure sensor. The present invention takes P1=VL, P2=0.9VL, P3=0.8VL, P4=0.7VL as an example. Figure 6 As shown. The four-position five-way solenoid valve outputs the final emergency brake pre-control pressure AC2 under the control of EBCU; the emergency solenoid valve loses power and conducts during emergency braking UB; the relay valve amplifies the flow of AC2 and outputs the emergency brake pressure to the brake cylinder of each basic brake unit. The schematic diagram of the new emergency brake system is shown in Figure 7 shown.

[0038] The empty and loaded vehicle valve outputs the corresponding pre-control pressure VL in proportion to the total air input and the empty spring pressure AS. Even if the internal pressure of the spring disappears due to air spring leakage or other reasons, the empty and loaded vehicle valve still has a safety function of a certain braking pressure.

[0039] The empty and loaded vehicle valve includes a single-stage empty and loaded vehicle valve and a double-stage empty and loaded vehicle valve. The present invention is described by taking a double-stage empty and loaded vehicle valve as an example.

[0040] The dual-stage empty and loaded vehicle valve outputs two types of curves, high and low pressure, by adjusting the gain and loss of electricity of the emergency switching solenoid valve. The train outputs a low pressure curve at high speed and a high pressure curve at low speed.

[0041] The two-stage empty and loaded vehicle valve is adjusted in a fixed ratio and the ratio cannot be adjusted.

[0042] The empty and loaded vehicle valve can adjust the VL adjusting screw and the AS adjusting bolt to adjust the VL and AS force values.

[0043] The plug-in type multi-proportional integrated pressure reducing valve is composed of four groups of proportional pressure reducing valves with different diaphragm areas. Figure 8 shown.

[0044] The plug-in multi-proportional integrated pressure reducing valve outputs the pre-control pressure VL as four pre-control pressures Pi after reducing the pressure in specific proportions.

[0045] The proportional pressure reducing valve can realize different inlet and outlet pressure reducing ratios by replacing diaphragms of different areas, thereby realizing convenient and adjustable output characteristics.

[0046] The proportional pressure reducing valve comprises a valve body, a valve stem, an O-ring, a diaphragm plate, a return spring and other parts. Fig. 9 .

[0047] The working principle of the proportional pressure reducing valve is that when emergency braking is performed, the VL pressure output by the empty and loaded vehicle valve enters the proportional pressure reducing valve, and the VL pressure acts on the lower surface of the diaphragm, pushing the valve stem to overcome the force of the spring (reset spring) and move upward, and the supply valve port opens to connect the input and output chambers. At the same time, the VL pressure flows into the upper chamber through the internal air hole to form the secondary side outlet pressure Pi. When the Pi pressure reaches the set value, the feedback chamber pressure acts on the diaphragm, which generates a downward force on the valve stem, and the valve is in a balanced state. If the VL pressure drops, the pressure acting on the lower side of the diaphragm becomes smaller, the valve stem will move downward, causing the valve stem to separate from the valve seat, and the pressure Pi will be discharged to the atmosphere through the internal air hole of the valve stem. The pressure Pi continues to decrease until the force on the valve stem is balanced, the valve stem contacts the valve seat again, and the exhaust hole is closed.

[0048] VL represents the pressure at the inlet end, Pi represents the pressure at the outlet end, S1 represents the effective area at the inlet end, and S2 represents the effective area at the outlet end. When friction is ignored and the valve stem is under balanced force, the pressure reduction ratio VL:Pi=S2:S1.

[0049] The valve stem has diaphragms with proportional effective areas at both ends. The effective area ratio of the diaphragms at the inlet end and the outlet end of each set of valve stems is different, so the pressure reduction ratio is different.

[0050] The specific ratio pressure reduction means that a certain ratio is maintained between the input pressure and the output pressure.

[0051] The four pre-control pressures of different proportions, VL, 0.9VL, 0.8VL, and 0.7VL, are pre-control pressures after VL is reduced in a specific proportion. VL means that the specific proportion is 1:1, 0.9VL means that the specific proportion is 10:9, which is 0.9 times the VL pressure, and so on.

[0052] The pressure sensor is connected to the EBCU and is used to monitor the VL, 0.9VL, 0.8VL and 0.7VL pressures output from the rear end of the plug-in multi-proportional integrated pressure reducing valve.

[0053] The four-position five-way solenoid valve is used to select and output one of the pressures VL, 0.9VL, 0.8VL, and 0.7VL; the EBCU can select and output the optimal brake pressure Pi according to the vehicle speed based on the monitoring data of the pressure sensor.

[0054] The four-position five-way solenoid valve needs to accommodate four air inlets (P1, P2, P3, P4) and one air outlet (OUT). Fig.10 .

[0055] The four-position five-way solenoid valve adopts a dual electric control structure, that is, two electromagnetic coils (coil a and coil b) are used to achieve switching of four different working positions.

[0056] The valve core design of the four-position five-way solenoid valve uses a sliding valve core with four positions, and the movement of the valve core is controlled by the electromagnetic coil to achieve the selection of different air inlets.

[0057] The switching principle of the four-position five-way solenoid valve is to change the position of the valve core by controlling the power-on / power-off state of the control coil a and the coil b, thereby selecting different air inlets and outlets to connect.

[0058] The four-position five-way solenoid valve has four working states:

[0059] (1) State 1: a loses power, b loses power, and the valve core is in the initial position. Connection state: P1 → OUT, which is the default state and is used to output VL pressure.

[0060] (2) State 2: a is energized, b is de-energized, coil a is energized, pushing the valve core to the right. Connection state: P2 → OUT, used to output 0.9VL pressure.

[0061] (3) State 3: a loses power, b gains power, coil b is energized, pushing the valve core to the left. Connection state: P3 → OUT, used to output 0.8VL pressure.

[0062] (4) State 4: a is energized, b is energized, both coils are energized at the same time, and the valve core moves to the rightmost position. Connection state: P4→ OUT, used to output 0.7VL pressure.

[0063] When the emergency solenoid valve is in the emergency braking UB condition, the safety loop of the emergency solenoid valve loses power and the emergency gas circuit is connected. The pressure output by the four-position five-way solenoid valve is input into the relay valve.

[0064] The relay valve is used to amplify the flow of the output emergency brake pre-control pressure AC2.

[0065] The emergency brake UB gas path flow direction of the present invention (taking P1 pressure as an example) is shown in Fig.11 .

[0066] Through the above technical solution, it can be seen that the present application has the following beneficial effects:

[0067] The solution proposed in the present invention utilizes proportional regulation technology to dynamically optimize the output of emergency brake pressure according to actual needs under different vehicle weight conditions by accurately controlling the pre-control pressure in the train emergency brake system. Specifically, the system combines the perception of the empty spring pressure (AS value) by the empty-weight vehicle valve and the specific proportional pressure reduction function of the plug-in multi-proportional integrated pressure reducing valve to provide more precise pressure regulation under different working conditions to ensure accurate matching of the brake pressure. This technical solution significantly improves the adaptability and accuracy of the brake system, allowing the train to adjust the appropriate brake pressure according to factors such as vehicle weight and speed.

[0068] By precisely adjusting the pressure under emergency braking conditions, the system can optimize the pre-control pressure (VL) in real time to output the final brake pressure (AC2) according to the vehicle speed and the load information fed back by the empty spring. Compared with the traditional linear adjustment mode, the proportional adjustment scheme of the present invention overcomes the disadvantage of the coarse precision of the empty and loaded vehicle valve output pressure, and provides a more refined adjustment capability. This not only improves the braking performance of the train under different vehicle weights and speeds, but also can significantly shorten the braking distance, ensuring that the train can stop more quickly in an emergency.

[0069] In addition, since the control of impact force during emergency braking is very important, the present invention effectively reduces the impact force during braking through precise pressure regulation, thereby reducing the fluctuation of adhesion between the train and the track and reducing the wear on the train and the track. The implementation of this technical solution will greatly improve the safety and stability of the train in emergency braking situations and provide more reliable protection for train operation.

Claims

1. A pressure regulating device for a train emergency brake system, characterized in that include: Empty and loaded vehicle valve, plug-in multi-proportional integrated pressure reducing valve, four-position five-way solenoid valve, pressure sensor, emergency solenoid valve and relay valve. At the rear end of the empty and loaded vehicle valve, the plug-in multi-proportional integrated pressure reducing valve is used to reduce the VL pressure in a specific proportion, and the pressure sensor is used to obtain the pressure value. Finally, the EBCU controls the four-position five-way solenoid valve to select and output a more accurate emergency brake pre-control pressure P. i , and then the flow is amplified through the relay valve to achieve precise adjustment of the emergency brake pressure.

2. A train emergency brake system pressure regulating device according to claim 1, characterized in that The empty and loaded vehicle valve outputs a corresponding amount of pre-control pressure VL in proportion to the total air input and the empty spring pressure AS value. The empty and loaded vehicle valve outputs two types of high and low pressure curves by adjusting the gain and loss of electricity of the emergency switching solenoid valve.

3. A train emergency brake system pressure regulating device according to claim 1, characterized in that The plug-in multi-proportional integrated pressure reducing valve is composed of four groups of proportional pressure reducing valves with different diaphragm areas, and outputs four pre-controlled pressures Pi (i=1, 2, 3, 4) after reducing the input VL pressure in different proportions.

4. A train emergency brake system pressure regulating device according to claim 3, characterized in that The four groups of proportional pressure reducing valves with different diaphragm plate areas have different ratios of effective diaphragm plate areas between the inlet end and the outlet end of the valve stem of each group.

5. A train emergency brake system pressure regulating device according to claim 4, characterized in that VL represents the inlet pressure, Pi represents the outlet pressure, S1 represents the effective area of ​​the inlet, and S2 represents the effective area of ​​the outlet. When friction is ignored and the valve stem is under balanced force, the pressure reduction ratio VL:Pi=S2:S1.

6. A train emergency brake system pressure regulating device according to claim 3, characterized in that The pressure sensor is connected to the EBCU, and is used to monitor the P1, P2, P3, and P4 pressures outputted from the rear end of the plug-in multi-proportional integrated pressure reducing valve.

7. A train emergency brake system pressure regulating device according to claim 6, characterized in that The pressure sensor transmits the collected pressure signal to the EBCU, and the EBCU obtains the optimal brake pressure according to the current vehicle speed matching, and outputs it to the emergency solenoid valve through the four-position five-way solenoid valve.

8. A train emergency brake system pressure regulating device according to claim 7, characterized in that The four-position five-way solenoid valve has the main function of switching between four working positions, controlling the flow of four decompressed gases from the input end to the output end, and selecting to output a specific proportion of the decompressed pressure.

9. A train emergency brake system pressure regulating device according to claim 7, characterized in that The emergency solenoid valve is turned on when it loses power under the emergency braking UB condition, and inputs the Pi pressure output by the four-position five-way solenoid valve into the relay valve.

10. A train emergency brake system pressure regulating device according to claim 9, characterized in that The relay valve is used to amplify the flow of the emergency brake pre-control pressure AC2, ie, Pi.

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