A method for sharing vertical load of a train air spring rubber air bag

Abstract

The application discloses a method for sharing vertical load of a train air spring rubber air bag, which is characterized in that: a magnetic repulsion force is generated on an upper cover plate of the air spring when the upper cover plate is subjected to a vertical overload impact, so as to reduce the air pressure in the rubber air bag under the overload condition. The method is characterized in that: an upper magnet and a lower magnet are arranged on the upper cover plate and below the upper cover plate respectively, and the upper magnet and the lower magnet have the same polarity at adjacent ends to generate the magnetic repulsion force. Meanwhile, the upper cover plate with the upper magnet is allowed to freely slide relative to the lower magnet in a horizontal direction. The method has the advantages that: the rubber air bag can keep good elasticity for a long time, and the air spring can keep good supporting and damping performance for a long time; and the rubber air bag can avoid high-pressure burst.

Description

Technical Field

[0001] This invention relates to train air springs, specifically to a method for distributing vertical loads to the rubber air bladders of train air springs, belonging to the field of rail transit technology. Background Technology

[0002] An air spring mainly consists of a lower auxiliary spring and an upper rubber air bladder.

[0003] The auxiliary spring has a rigid spindle, and the outer periphery of the spindle is a stack of rubber piles that are vulcanized together with the spindle and stacked outward and upward. The rubber piles have multiple layers of metal spacers that are vulcanized together with the rubber piles from the inside out. The outer periphery of the rubber piles is a metal outer jacket that is vulcanized together with the rubber piles. The top of the metal outer jacket is a support plate.

[0004] The top of the rubber airbag is a cover plate, and the outer periphery of the bottom surface of the cover plate and the outer periphery of the metal jacket are sealed by an annular rubber bladder to form a rubber airbag.

[0005] The support plate is equipped with a wear plate, which is used to catch the sinking top cover plate when the rubber airbag is suddenly depressurized, and to allow the top cover plate to slide on the wear plate.

[0006] The bottom of the spindle is the mounting base for the air spring.

[0007] Air springs are installed on the bogies to support the train carriages and to provide multi-directional vibration damping during operation.

[0008] Because the auxiliary spring is located at the bottom of the rubber air bladder, it bears the entire load above the rubber air bladder, while the spindle is the support for the entire air spring.

[0009] Rubber airbags play a primary role in vibration damping within air springs, and the internal air pressure increases with the vertical load. As the air pressure changes, the airbag's outer layer continuously expands and contracts. This repeated expansion and contraction, especially under overload conditions caused by uneven road surfaces and high-speed vertical overload impacts, can lead to fatigue of the rubber outer layer, reducing its elasticity and severely impacting the train's vibration damping effect, thus shortening the airbag's lifespan.

[0010] The rubber body used to manufacture rubber stacks can recover its deformation under load impact, a property utilized for vibration damping in various components. However, when applied to trains as rubber stacks supporting airbags, the rubber stacks undergo irreversible creep due to long-term heavy pressure and vertical impact. This creep is accelerated by repeated overload impacts, causing the auxiliary spring height to gradually decrease, resulting in a lower overall height of the air spring. To compensate for the reduced height due to the auxiliary spring's creep, a differential pressure inflation device is activated to inflate the airbag and increase its height. However, this method of compensating for height by inflating the airbag further increases the expansion pressure on the rubber bladder, making it more susceptible to fatigue and aging.

[0011] In addition, the rubber airbag is subjected to repeated overload impacts under high pressure for a long time. A direct threat is that the rubber bladder itself and the joint between the rubber bladder and the top cover plate and metal jacket are prone to bursting, which can lead to operational failures.

[0012] To address the aforementioned issues, our company has conducted a series of studies. Furthermore, through a search of relevant research in this field, we have found no studies specifically addressing these problems. Our company believes that effectively resolving the issue of increased air pressure in rubber airbags due to overload impacts is of great significance for maintaining good vibration reduction performance in trains over the long term and extending the service life of air springs. Summary of the Invention

[0013] The technical problem to be solved by this invention is: how to distribute the vertical load to the rubber airbag without affecting the horizontal stiffness of the air spring, at least to reduce the air pressure under overload impact, so as to maintain the good vibration damping performance of the air spring and extend its service life in the long term.

[0014] To address the above problems, the technical solution proposed by this invention is as follows:

[0015] One method for sharing the vertical load on the rubber airbag of a train air spring is to ensure that the upper cover plate of the air spring, which bears the pressure of the carriage, is subjected to an upward magnetic repulsive force that gradually increases in strength when it is subjected to a vertical overload impact and descends, thereby reducing the air pressure inside the lower rubber airbag.

[0016] Furthermore, an upper magnet and a lower magnet are respectively installed on the upper cover plate and below the upper cover plate, so that the polarities of the adjacent ends of the upper magnet and the lower magnet are the same, thus generating a repulsive force.

[0017] Furthermore, the upper cover plate on which the upper magnet is mounted can slide freely in the horizontal direction relative to the lower magnet.

[0018] Furthermore, the lower magnet is placed on the rubber stack of the auxiliary spring, so that at least when the upper cover plate is subjected to a vertical overload impact, part of the impact force acts directly on the rubber stack of the auxiliary spring through the repulsive force formed between the upper and lower magnets.

[0019] Furthermore, the lower magnet is placed on the mandrel, so that at least when the upper cover plate is subjected to a vertical overload impact, a portion of the impact force acts directly on the mandrel through the repulsive force formed between the upper and lower magnets.

[0020] Furthermore, the lower magnet is mounted on a support plate under the wear plate.

[0021] Furthermore, the upper magnet and the lower magnet are respectively an upper permanent magnet and a lower permanent magnet; or, the upper magnet and the lower magnet are respectively an upper electromagnet and a lower electromagnet.

[0022] Furthermore, when the upper magnet and the lower magnet are respectively the upper electromagnet and the lower electromagnet, an induction control system is set up to acquire the distance information between the upper cover plate and the wear plate and convert the information into an electronic control command. The upper electromagnet and the lower electromagnet are controlled to only be energized and magnetized when the distance between the upper cover plate and the wear plate is compressed to the overload distance range.

[0023] Furthermore, a vertically extendable compression spring is provided between the lower magnet and the spindle, so that the vertical height of the lower magnet can be changed when it is subjected to varying repulsive forces.

[0024] Furthermore, the upper magnet and the lower magnet are respectively an upper permanent magnet and a lower permanent magnet; the maximum stiffness of the compression spring is limited so that there is always a gap between the upper cover plate and the lower permanent magnet and its mounting parts and the upper cover plate; and the height of the upper end face of the lower permanent magnet is higher than the height of the wear plate.

[0025] Beneficial effects: This invention utilizes magnetic repulsion to distribute the load and impact applied to the upper cover plate of the rubber air bladder on the air spring. At least in cases of overload and overload impact, it can reduce the pressure and vertical impact force borne by the rubber air bladder, making the peak pressure inside the rubber air bladder much lower than that of traditional rubber air bladders. The rubber air bladder skin will not bear the ultimate expansion pressure, effectively avoiding or delaying rubber skin fatigue. Therefore, the following results are achieved:

[0026] 1. To ensure that the rubber airbag maintains good elasticity over a long period of time, thereby enabling the air spring to maintain good support and vibration damping performance over a long period of time;

[0027] 2. It can prevent the rubber airbag from bursting under high pressure. Attached Figure Description

[0028] Figure 1 This is a cross-sectional schematic diagram of the air spring in Example 1;

[0029] Figure 2This is a cross-sectional schematic diagram of the air spring in Example 2;

[0030] Figure 3 This is a cross-sectional schematic diagram of the air spring in Example 3;

[0031] Figure 4 This is a cross-sectional schematic diagram of the air spring in Example 4;

[0032] Figure 5 This is a cross-sectional schematic diagram of the air spring in Example 5.

[0033] In the diagram: 1. Rubber airbag; 101. Upper cover plate; 102. Airbag skin; 2. Rubber stack; 201. Support plate; 202. Wear plate; 203. Metal jacket; 3. Upper magnet; 301. Upper electromagnet; 302. Upper permanent magnet; 4. Lower magnet; 401. Lower electromagnet; 402. Lower permanent magnet; 5. Mandrel; 6. Compression spring; 7. Sensor. Detailed Implementation

[0034] The present invention will be further described below with reference to embodiments and accompanying drawings:

[0035] like Figure 1 As shown, for ease of explanation, the load borne by the air spring cover plate 101 of the train car is divided into normal load below a certain pressure and overload load exceeding a certain pressure. Hereinafter, normal load is simply referred to as constant load, and overload load is simply referred to as overload. Furthermore, the vertical impact encountered by the cover plate 101 due to road irregularities while the train is running under constant load is called constant load impact, and the vertical impact encountered by the cover plate 101 due to road irregularities while the train is running under overload conditions is called overload impact. The maximum overload impact encountered by the cover plate 101 is called ultimate load impact.

[0036] Example 1

[0037] like Figure 1 As shown, a method for sharing vertical loads on the rubber airbags of train air springs involves ensuring that the upper cover plate 101, which bears the pressure of the carriage, experiences an upward, gradually increasing magnetic repulsive force, at least when subjected to a vertical overload impact. This reduces the ultimate pressure of the air inside the rubber airbag 1 during an overload impact. In this way, the magnetic repulsive force partially shares the pressure on the upper cover plate 101 when it is under overload and experiences an overload impact, reducing the pressure on the rubber airbag 1. This, in turn, reduces the fluctuation range of the air pressure inside the rubber airbag 1 during an overload impact. This not only significantly reduces the expansion pressure on the airbag skin 102 of the rubber airbag 1 but also reduces the amplitude of the expansion pressure change, thereby maintaining the good elasticity of the rubber airbag 1 for a longer period and reducing the risk of sudden rupture of the rubber airbag 1.

[0038] The reduction in the increase of air pressure inside the rubber airbag 1 during overload impact refers to the fact that the closer the two magnets that generate magnetic repulsion are, the greater the repulsion force becomes. In other words, as the upper cover plate 101 descends, the upward magnetic repulsion force it receives rapidly increases from weak to strong, and the pressure shared by the rubber airbag 1 also increases rapidly, preventing the rubber airbag 1 from being compressed significantly. This can prevent the air pressure inside the rubber airbag 1 from rising linearly, which will be reflected in the following further implementation.

[0039] The upper cover 101, which enables the air spring to bear the pressure of the carriage, to be subjected to an upward magnetic repulsive force that increases from weak to strong when subjected to a vertical overload impact, as described here means that the upper cover 101 can also be subjected to an upward magnetic repulsive force under normal load and overload conditions; and the upper cover 101 can also be subjected to an upward magnetic repulsive force that increases from weak to strong when subjected to a normal load impact.

[0040] The above method involves setting an upper magnet 3 and a lower magnet 4 on the upper cover plate 101 and below the upper cover plate 101 respectively, so that the adjacent ends of the upper magnet 3 and the lower magnet 4 have the same polarity and generate a repulsive force. The phrase "the adjacent ends of the upper magnet 3 and the lower magnet 4 have the same polarity" means that the adjacent ends of the upper magnet 3 and the lower magnet 4 have the same polarity as either N pole or S pole.

[0041] When implementing the above method, it is necessary to consider not affecting the stiffness of the air spring in the horizontal direction. Therefore, the upper cover plate 101 on which the upper magnet 3 is mounted is designed to slide freely in the horizontal direction relative to the lower magnet 4. Preferably, there is always a gap between the upper cover plate 101 and the lower magnet 4 and the mounting component on which the lower magnet 4 is mounted.

[0042] The above method involves placing the lower magnet 4 on the rubber stack 2 of the auxiliary spring. At least when the upper cover plate 101 experiences a vertical overload impact, a portion of the impact force acts directly on the rubber stack 2 of the auxiliary spring through the repulsive force formed between the upper magnet 3 and the lower magnet 4, thereby reducing the pressure on the rubber airbag. Specifically, the lower magnet 4 is installed on the support plate 201 under the wear plate 202, and the support plate 201 is fixed to the top of the metal jacket 203 of the rubber stack 2.

[0043] As an option, in this embodiment, both the upper magnet 3 and the lower magnet 4 are made as electromagnets, namely upper electromagnet 301 and lower electromagnet 401. Specifically, an inductive control system is set up to acquire the distance information between the upper cover plate 101 and the wear plate 202 and convert this information into electronic control commands. The upper electromagnet 301 and lower electromagnet 401 are only energized and magnetized when the distance between the upper cover plate 101 and the wear plate 202 is compressed to an overload range. The inductive control system includes a sensor 7. This setup eliminates the need for energization under constant load, thus saving electricity. The advantage of using electromagnets is that the required magnetic field strength can be obtained, and a sufficiently large magnetic repulsive force can be obtained when encountering extreme load impacts.

[0044] This method allows for the elimination of the need to energize the upper electromagnet 301 and lower electromagnet 401 under normal load conditions. However, under overload conditions, the upper cover 101 descends to a set height. At this height, the induction control system energizes the upper and lower electromagnets 301 and 401, creating a magnetic repulsion between them. This helps to alleviate the pressure exerted on the carriage by the rubber airbag 1 under overload conditions. When the train travels on uneven roads, and the upper cover 101 experiences a vertical overload impact causing it to continue sinking, the upper and lower electromagnets 301 and 401 will move closer together, generating an increasingly stronger magnetic repulsion. This further alleviates the overload impact force on the rubber airbag 1, which is far greater than the pressure exerted on the carriage under overload conditions. The pressure and impact force thus distributed act on the rubber stack 2, thereby maintaining the good elasticity of the rubber airbag 1 for a long time and reducing the risk of sudden rupture.

[0045] Example 2

[0046] like Figure 2 As shown, the difference from Embodiment 1 is that in this embodiment, both the upper magnet 3 and the lower magnet 4 are permanent magnets, namely the upper permanent magnet 302 and the lower permanent magnet 402. Using permanent magnets as the upper magnet 3 and the lower magnet 4 can eliminate the dependence on electricity and has a simple structure. More importantly, it can also share the load of the rubber airbag 1 under no-load and constant-load conditions.

[0047] Example 3

[0048] like Figure 3 As shown, the difference from Embodiment 1 is that the lower magnet 4 is mounted on the mandrel 5, so that at least when the upper cover plate 101 experiences a vertical overload impact, a portion of the impact force acts directly on the mandrel 5 through the repulsive force formed between the upper magnet 3 and the lower magnet 4. The upper magnet 3 and the lower magnet 4 are respectively an upper permanent magnet 302 and a lower permanent magnet 402, or they can be an upper electromagnet 301 and a lower electromagnet 401. The advantage of this arrangement is that it not only shares the vertical load for the rubber airbag but also shares the vertical load for the rubber stack 2, delaying the creep process of the rubber stack 2, which is more conducive to achieving the purpose of this invention (the problem solved and the effect obtained).

[0049] Example 4

[0050] like Figure 4As shown, this embodiment is a further measure of Embodiment 3, which involves installing a vertically extendable compression spring 6 between the lower magnet 4 and the spindle 5, allowing the lower magnet 4 to change its vertical height when subjected to varying repulsive forces. Compared to the rigid force applied to the lower magnet 4 in Embodiments 1, 2, and 3, this embodiment makes the lower magnet 4 subject to flexible force, thus enabling the combined adjustment of the vertical stiffness of the air spring with the rubber airbag, ensuring the air spring's vertical stiffness is at its optimal state. The upper magnet 3 and the lower magnet 4 can be electromagnets or permanent magnets.

[0051] Example 5

[0052] like Figure 5 As shown, this embodiment is a further measure of embodiment four. The upper magnet 3 and the lower magnet 4 are the upper permanent magnet 302 and the lower permanent magnet 402, respectively. The maximum stiffness of the compression spring 6 is limited so that there is always a gap between the upper cover plate 101 and the lower permanent magnet 402 and its mounting parts and the upper cover plate 101. The height of the upper end face of the lower permanent magnet 402 is higher than the height of the wear plate 202. In this way, the lower permanent magnet 402 can be closer to the upper permanent magnet 302, maximizing the repulsive force between the upper permanent magnet 302 and the lower permanent magnet 402, which have limited magnetic field strength. However, after the upper permanent magnet 302 and the lower permanent magnet 402 are close together, if the stiffness of the compression spring 6 is too large and the magnetic field strength of the upper permanent magnet 302 and the lower permanent magnet 402 is limited, then when the upper cover plate 101 encounters an extreme impact, the upper cover plate 101 and the lower permanent magnet 402 and its mounting parts will touch, affecting the horizontal stiffness of the rubber airbag 1. This embodiment can maximize the magnetic repulsion force by relying on permanent magnets without using electromagnets, and can keep the vertical stiffness of the air spring in the optimal state.

[0053] In the embodiments involving the lower electromagnet described above, the specific exit position of the power supply line of the lower electromagnet is not shown in the figure. It is mainly considered to lead out through the opening in the upper cover plate 101, or through the opening in the metal jacket 203, but both require high-pressure resistant sealing at the opening.

[0054] The above embodiments are only used to describe the present invention more clearly, and should not be regarded as limiting the scope of protection covered by the present invention. Any equivalent modifications should be regarded as falling within the scope of protection covered by the present invention.

Claims

1. A method for distributing vertical loads for rubber airbags in train air springs, characterized in that... The upper cover plate (101) that bears the pressure of the car body is subjected to an upward magnetic repulsive force, which gradually increases in strength, at least when it is subjected to a vertical overload impact, so as to reduce the air pressure in the rubber airbag (1); an upper magnet (3) and a lower magnet (4) are respectively installed on the upper cover plate (101) and below the upper cover plate (101), so that the polarities of the adjacent ends of the upper magnet (3) and the lower magnet (4) are the same and generate a repulsive force; the upper cover plate (101) with the upper magnet (3) installed can slide freely in the horizontal direction relative to the lower magnet (4); the lower magnet (4) is set on the rubber stack (2) of the auxiliary spring, so that at least when the upper cover plate (101) encounters a vertical impact, it can be subjected to an upward magnetic repulsive force, which gradually increases in strength, so as to reduce the air pressure in the rubber airbag (1); an upper magnet (3) and a lower magnet (4) are respectively installed on the upper cover plate (101) and below the upper cover plate (101), so that the upper cover plate (101) can slide freely in the horizontal direction relative to the lower magnet (4); the lower magnet (4) is set on the rubber stack (2) of the auxiliary spring, so that at least when the upper cover plate (101) encounters a vertical overload impact, it can be subjected to an upward magnetic repulsive force, which gradually increases in strength, so as to reduce the air pressure in the rubber airbag (1). When an overload impact occurs, a portion of the impact force is directly applied to the rubber stack (2) of the auxiliary spring through the repulsive force formed between the upper magnet (3) and the lower magnet (4); the lower magnet (4) is placed on the spindle (5), so that at least when the upper cover plate (101) encounters a vertical overload impact, a portion of the impact force is directly applied to the spindle (5) through the repulsive force formed between the upper magnet (3) and the lower magnet (4); the lower magnet (4) is mounted on the support plate (201) under the wear plate (202); a vertically extendable compression spring (6) is provided between the lower magnet (4) and the spindle (5) so that the lower magnet (4) can change its vertical height when subjected to a changing repulsive force.

2. The method for distributing vertical loads for train air spring rubber airbags as described in claim 1, characterized in that: The upper magnet (3) and the lower magnet (4) are respectively an upper permanent magnet (302) and a lower permanent magnet (402); or, the upper magnet (3) and the lower magnet (4) are respectively an upper electromagnet (301) and a lower electromagnet (401).

3. The method for distributing vertical loads to the rubber airbags of train air springs as described in claim 2, characterized in that: When the upper magnet (3) and the lower magnet (4) are the upper electromagnet (301) and the lower electromagnet (401) respectively, an induction control system is set up to acquire the distance information between the upper cover plate (101) and the wear plate (202) and convert the information into an electronic control command. The upper electromagnet (301) and the lower electromagnet (401) are controlled to only be energized and magnetized when the distance between the upper cover plate (101) and the wear plate (202) is compressed to the overload distance range.

4. The method for distributing vertical loads for train air spring rubber airbags as described in claim 1, characterized in that: The upper magnet (3) and the lower magnet (4) are respectively the upper permanent magnet (302) and the lower permanent magnet (402); the maximum stiffness of the compression spring (6) is limited so that there is always a gap between the upper cover plate (101) and the lower permanent magnet (402) and their mounting parts and the upper cover plate (101); the height of the upper end face of the lower permanent magnet (402) is higher than the height of the wear plate (202).

Images