Multifunctional gasket for rails

Abstract

The utility model discloses a kind of multifunctional gaskets for track, applied to railway fastener system, including gasket body and its internal elastic structure, gasket body has continuous closed boundary, the elastic structure includes the multilayer buffer cell layer stacked, each layer buffer cell layer includes the structural cell of periodic arrangement, the structural cell includes the basic unit formed by connecting according to central symmetry topological configuration, the basic unit surface is equipped with central hole area and edge hole area.The utility model has the following advantages high-efficiency energy absorption shock absorption: by setting multilayer buffer cell layer evenly disperses pressure, reduces local stress concentration, improves overall stability;Lightweight high strength: by central symmetry topological configuration integration basic unit to realize maximum rigidity and strength with minimum material consumption;Excellent durability: gasket body combines multilayer buffer cell layer design, elastic recovery ability is strong, prolongs service life;Economical: reduce maintenance cost, convenient transportation and replacement.

Description

Technical Field

[0001] This utility model relates to the field of rail transit equipment technology, and in particular to a multifunctional pad for rail tracks. Background Technology

[0002] Rail transit refers to a type of transportation vehicle or system that requires operating vehicles to run on specific tracks. The national standard "Common Terminology of Urban Public Transportation" defines urban rail transit as "a general term for rapid, high-capacity public transportation that is usually powered by electricity and operates in a wheel-rail mode." With the diversified development of train and railway technology, rail transit has shown more and more types, not only spreading to long-distance land transportation, but also widely used in medium and short-distance urban public transportation. With the rapid development of railway transportation, railway track mileage is increasing year by year. As a key component of the railway track system, track pads directly affect the stability and safety of train operation. In existing technologies, elastic track pads are mainly used to buffer vibrations and impacts during train operation, but they generally suffer from the following problems: (1) Material aging problem: Traditional rubber gaskets are prone to aging, which leads to increased hardness, reduced elasticity, and a significant decrease in shock absorption effect; (2) Insufficient durability: Existing gaskets need to be replaced frequently, which increases maintenance costs; (3) Material limitations: Rubber materials have poor oil and solvent resistance and large compression set; thermoplastic elastic materials have limited high temperature resistance and insufficient elastic recovery ability; microporous foam materials have low mechanical properties and poor weather resistance and flame retardancy. Utility Model Content

[0003] This utility model discloses a multifunctional track shim, which improves upon existing structures and shortcomings to provide a multifunctional track shim with better practical value. To achieve the above objectives, the present invention adopts the following technical solution: A multifunctional track shim, used in railway fastening systems, includes a shim body and its interior. The elastic structure includes a gasket body with a continuous closed boundary. The elastic structure comprises multiple layers of stacked buffer cells, each layer of buffer cells including periodically arranged structural cells. The structural cells include basic units connected in a centrally symmetric topological configuration. The surface of the basic unit is provided with a central hole region and an edge hole region. In some embodiments, the centrally symmetric topological configuration is one of a regular hexagon, a square, or a circular rotationally symmetric configuration. In some embodiments, the edge hole region includes edge cut-out holes located in the middle of the basic unit edge line and corner cut-out holes at the corners. In some embodiments, the total area of ​​the edge cutting holes and the corner cutting holes accounts for 30%-70% of the surface area of ​​the basic unit. In some embodiments, the number of stacked layers of the multilayer buffer cell layer is 2-20, and the adjacent structural cells are rotated and misaligned by 0°-60°. In some embodiments, the width W of the continuous closed boundary satisfies: 3mm≤W≤15mm, and the relationship between the width W of the continuous closed boundary and the length L of the gasket is: 0.03L≤W≤0.1L. In some embodiments, bolt mounting holes are provided on the continuous closed boundary, and the diameter of the bolt mounting holes is clearance-fitted with the track spikes. In some embodiments, the minimum width Lm of the connection area between the basic units satisfies: 0.1mm≤Lm≤0.5mm. In some embodiments, the gasket body is made of a polymer elastic material and is integrally molded. The multifunctional track pad provided by this utility model has the following advantages: 1. High-efficiency energy absorption and vibration reduction: By setting up multiple layers of buffer cells to evenly distribute pressure, local stress concentration is reduced and overall stability is improved; 2. Lightweight and high strength: The basic unit is integrated through a centrally symmetric topological configuration to achieve maximum stiffness and strength with minimal material usage; 3. Excellent durability: The gasket body incorporates a multi-layered buffer cell design, resulting in strong elastic recovery capability. Extend service life; 4. Economic efficiency: Reduces maintenance costs and facilitates transportation and replacement. Attached Figure Description

[0004] Figure 1 A three-dimensional structural diagram of a railway fastening system; Figure 2 for Figure 1 The diagram shows a cross-sectional view of the railway fastening system. Figure 3 This utility model proposes a structural schematic diagram of the basic unit of a multifunctional track pad; Figure 4 Another structural schematic diagram of the basic unit of a multifunctional track pad proposed in this utility model; Figure 5 This is a structural diagram of the structural cell of a multifunctional track pad proposed in this utility model; Figure 6 This is a schematic diagram of the structure of a multifunctional track pad proposed in this utility model; Figure 7This is a cross-sectional schematic diagram of a multifunctional track pad proposed in this utility model. In the attached diagram: 11. Continuous closed boundary; 12. Multi-layer buffer cell layer; 13. Structural cell; 14. Basic unit; 15. Central cavity region; 16. Edge cavity region; 161. Edge cut-out hole; 162. Corner cut-out hole; 2. Track baffle; 3. Threaded rail spike; 4. Rail; 5. Elastic clip; 6. Rail pad; 7. Concrete pillows. Detailed Implementation

[0005] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and marked in the accompanying drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application. Reference Figures 1 to 7 In a preferred embodiment, a multifunctional track pad, applied to a railway fastening system, includes a pad body and its internal elastic structure. The pad body has a continuous closed boundary 11. The elastic structure includes stacked multi-layered buffer cell layers 12. Each buffer cell layer includes periodically arranged structural cells 13. Each structural cell 13 includes at least three perforated basic units 14 connected in a centrally symmetric topological configuration. The surface of each basic unit 14 has a central perforated region 15 and an edge perforated region 16. Figure 1 and Figure 2 As shown, in some embodiments, the railway fastening system includes a multi-functional track pad, threaded spikes 2, rails 3, elastic clips 4, rail pads 5, track guards 6, and a concrete sleeper 7. The multi-functional track pad is mounted on the top of the concrete sleeper 7. The multi-functional track pad has track guards 6 at both ends, which are respectively interference-fitted with the track guards 6. Elastic clips 4 are provided above both track guards 6. The threaded spikes 2 pass through the elastic clips 4, track guards 6, and multi-functional track pads in sequence to set the multi-functional track pad on the concrete sleeper 7. Rails 3 are provided on the multi-functional track pads. Rails 3 are positioned between the two track guards 6, and both ends of rails 3 are respectively interference-fitted with the two track guards 6. A rail pad 5 is provided between rails 3 and the multi-functional track pad for cushioning. Specifically, such as Figure 3 and Figure 4As shown, the basic unit 14 is a polygonal sheet. In this embodiment, the basic unit 14 is a square sheet with a side length H = 2 mm. The central hole region 15 includes a central main hole and a through hole located at the geometric center of the basic unit 14. The shape of the through hole includes ellipse / circle / polygon. In some embodiments, the edge hole region 16 includes an edge cut-out hole 161 located in the middle of the edge of the basic unit and a corner cut-out hole 162 located at the corner. The total area of ​​the edge cut-out hole 161 and the corner cut-out hole 162 accounts for 30%-70% of the surface area of ​​the basic unit 14. The corner cut-out hole 162 is 1 / 4-1 / 2 of the complete hole. The minimum solid connection width between adjacent units is 0.1-0.5 mm. In some embodiments, the gasket body is made of a polymer elastic material, and the gasket body is integrally molded. Specifically, such as Figure 7 As shown, the gasket body has a perforated hexagonal honeycomb structure inside, which is integrally formed using additive manufacturing technology. The material selected is thermoplastic polyurethane, rubber, or polymer composite material with a Shore hardness of 60A-95A. The overall dimensions of the gasket body are 160mm × 145mm × 8mm, and the boundaries and connecting pores are dense. It is equipped with φ25mm bolt holes to accommodate fastener anchoring. There are 53 / 51 structural cells arranged in 13 alternating rows along the length direction, and a total of 41 rows in the width direction (21 rows of 53 cells, 20 rows of 51 cells). Furthermore, at the level of basic unit 14, polygonal sheets are used as the basic load-bearing units. The central main hole on its surface serves to release vertical stress, while the secondary holes distributed in the middle and corners of the edges are dedicated to shear stress conduction. Taking a preferred square unit as an example, when the side length is set in the range of 1-5mm, the major axis of the central elliptical hole maintains a ratio of 0.4-0.6 times to the side length of the unit, ensuring that the hole wall has sufficient buckling resistance. The corner cut-out holes adopt an optimized design with a radius of curvature of not less than 0.2 times the minor axis, which can effectively suppress stress concentration in the 45° direction. The units are connected by a 0.1-0.5mm wide connecting area to form an elastic hinge. This key dimension ensures structural continuity and provides controllable rotational flexibility. In some embodiments, the minimum width Lm of the connecting area between basic units 14 satisfies: 0.1mm≤Lm≤0.5mm. like Figure 5As shown, structural cell 13, as a secondary functional carrier, integrates basic unit 14 through a centrally symmetric topological configuration. In the preferred hexagonal configuration, six basic units 14 are hinged circumferentially to form a regular hexagonal frustum cell with a side length of 1.5-3 mm. Its unique 120° connection angle keeps the vertical stiffness fluctuation within 5%, completely eliminating the anisotropic defects of traditional quadrilateral meshes. For special working conditions, it can be switched to a quadrilateral or circular configuration: the cross-connected quadrilateral cell can increase axial stiffness by 20%, suitable for bridge expansion joint sections; while the tangentially arranged circular cell significantly enhances the ability to resist the penetration of corrosive media, especially suitable for the humid environment of tunnels. In some embodiments, the centrally symmetric topological configuration is a regular hexagonal, One of the rotationally symmetric configurations of a square or a circle. like Figure 6 As shown, in some embodiments, the multi-layer buffer cell layer 12 has 2-20 stacked layers, with adjacent structural cells exhibiting a rotational misalignment of 0°-60°. Specifically, the construction of the multi-layer buffer cell layer 12 embodies system-level innovation. In the planar extension dimension, an alternating row arrangement pattern is adopted to achieve seamless cell tiling—alternating between rows of 53 and 51 cells in the length direction to form a self-balancing stress grid. In the thickness direction, 2-20 cell layers are stacked along the Z-axis, with a controllable rotational misalignment of 0°-60° applied between layers. The selection of this misalignment angle has a clear functional orientation: a 30° misalignment is preferred for high-speed passenger dedicated lines. To suppress 300Hz wheel-rail resonance, heavy-load lines employ a 15° offset to enhance axial stability, while small-radius curves use a 45° offset to compensate for lateral deformation. The number of layers is precisely calculated based on dynamic load requirements, following the formula n=Fmax / （ 25. kunit ） Where Fmax is the design maximum wheel load, and kunit represents the single-layer stiffness. For example, in a heavy-load condition with an axle load of 30t, when the single-layer stiffness is 15kN / mm, a safe distribution of the 170kN load can be achieved by stacking six layers. In some embodiments, the width W of the continuous closed boundary 11 satisfies: 3mm ≤ W ≤ 15mm, and the relationship between the width W of the continuous closed boundary 11 and the length L of the shim is: 0.03L ≤ W ≤ 0.1L. In some embodiments, bolt mounting holes are provided on the continuous closed boundary 11, and the diameter of the bolt mounting holes is clearance-fitted with the road spike, with a diameter tolerance of ±0.5mm. Specifically, the boundary reinforcement structure, as a key engineering adaptation, includes two major elements: the continuous closed boundary 11 and the bolt mounting holes. The width of the compacted boundary is determined according to the triple constraint principle: the maximum value among 0.5 times the bolt hole diameter, 0.03 times the shim length, and the lower limit of 3mm. This design enables the road spike anchorage zone to form a stress diffusion angle of ≥45°. Finite element analysis shows that when the boundary width is 5mm, the maximum stress in the anchorage zone is reduced to 2.1MPa. The bolt mounting holes are subject to precise tolerance control, with the hole diameter designed to be 0.8-1.0mm larger than the road spike diameter, and with a machining error of ±0.3mm, ensuring both smooth installation and maintaining a 98% pull-out resistance retention rate. A special variant embodiment was developed for extreme environmental conditions. The cold-resistant gasket compensates for low-temperature embrittlement of the material by thickening the basic unit 14 to 0.35 mm, while simultaneously increasing the curvature of the corner cut-out holes to 0.8 mm. This utilizes the negative correlation between the radius of curvature and the stress concentration factor (αt = α0 . e__0.02). ( τ+40 ） This reduces the corner stress concentration factor by 40% under -40℃ operating conditions. The high flame-retardant gasket adopts a composite modification scheme: 25% aluminum hydroxide and 5% carbon nanotubes are added to the thermoplastic polyurethane matrix, and the pore area ratio is compressed to 35% to reduce the flame penetration path, and the boundary width is expanded to 8mm to form a stable carbonization barrier. In the additive manufacturing stage, a laser sintering layer thickness of 0.1-0.15mm is used to ensure the forming accuracy of a 0.25mm thin-walled structure, and the hole contour error is strictly controlled within ±0.05mm to prevent stress concentration point shift. During interlayer fusion, an ambient temperature of 10-15℃ above the material's glass transition temperature is maintained, along with a compaction pressure of 0.3-0.5MPa, ensuring both layer... Intermolecular diffusion bonding prevents cellular structure collapse. In the post-treatment stage, vibration aging at a frequency of 50 Hz is performed to eliminate residual stress, and a hydrophobic coating with a contact angle >110° is applied to improve weather resistance. The working principle is as follows: When the wheel load is transmitted to the pad body through the rail, the first-order energy dissipation occurs at the level of the basic unit 14: the vertical load forces the thin wall of the basic unit 14 to elastically bend towards the central hole region 15, forming a ring-shaped stress diffusion field at the edge of the hole, converting the point impact into distributed stress; at the same time, the shear load drives the corner cut-out hole 162 of the edge hole region 16 to undergo directional deformation, absorbing the lateral vibration energy through the torsional deformation of the thin wall at a 45° angle. In the second-order energy conversion stage, the centrally symmetric topological configuration of the structural cell 13 plays a core role. The hinged connection area (Lm=0.25mm) of the six basic units in the hexagonal structural cell 13 forms an elastic axis of rotation, converting the vertical pressure into the overall contraction deformation of the cell—during the synchronous inward inclination of the six side walls, the included angle between the units elastically changes from 120° to the range of 100°-110°, and this geometric deformation stores 60% of the impact kinetic energy as structural strain energy. For lateral loads, the hexagonal topology, through the tension-compression coupling effect of the cell diagonals, transforms the shear force into the coordinated deformation of three sets of opposing sidewalls, achieving isotropic energy dissipation. The third-order broadband modulation is achieved by a multi-layer buffer cell layer 12. When the vibration frequency is <100Hz, each cell layer deforms in phase, mainly relying on the bending of the thin wall of the unit to dissipate energy; when the frequency rises to the 100-300Hz range, the 30° misalignment design excites interlayer interface sliding friction, converting vibration energy into heat energy; when the frequency is >300Hz, the misaligned stacking forms a phonon bandgap, and high-frequency waves undergo Bragg scattering in the cell-gap alternating structure, with measured transmission loss exceeding 15dB. All content not described in detail in this specification belongs to the prior art known to those skilled in the art. The above description is merely a preferred embodiment of this utility model, but the protection scope of this utility model is not limited thereto. The substitutions may be replacements for some structures, devices, or method steps, or they may be complete technical solutions. Equivalent substitutions or modifications made based on the technical solution and inventive concept of this utility model should all be covered within the protection scope of this utility model.

Claims

1. A multifunctional track shim, applied in railway fastening systems, comprising a shim body and its internal elastic structure, characterized in that, The gasket body has a continuous closed boundary (11), and the elastic structure includes a multi-layer buffer cell layer (12) stacked together. Each buffer cell layer includes periodically arranged structural cells (13). The structural cells (13) include basic units (14) connected in a centrally symmetric topological configuration. The surface of the basic unit (14) is provided with a central hole region (15) and an edge hole region (16).

2. The multifunctional track pad according to claim 1, characterized in that, The centrally symmetric topological configuration is one of the following: a regular hexagon, a square, or a circular rotationally symmetric configuration.

3. The multifunctional track pad according to claim 1, characterized in that, The edge hole region (16) includes an edge cut-out hole (161) located in the middle of the basic unit edge line and a corner cut-out hole (162) at the corner.

4. The multifunctional track pad according to claim 3, characterized in that, The total area of ​​the edge cutting hole (161) and the corner cutting hole (162) accounts for 30%-70% of the surface area of ​​the basic unit (14).

5. The multifunctional track pad according to claim 1, characterized in that, The number of stacked layers of the multilayer buffer cell layer (12) is 2-20, and the adjacent structural cells are rotated and misaligned by 0°-60°.

6. The multifunctional track pad according to claim 1, characterized in that, The width W of the continuous closed boundary (11) satisfies: 3mm ≤ W ≤ 15mm, and the relationship between the width W of the continuous closed boundary (11) and the length L of the gasket is: 0.03L ≤ W ≤ 0.1L.

7. The multifunctional track pad according to claim 1, characterized in that, The continuous closed boundary (11) is provided with bolt mounting holes, the diameter of which is matched with the clearance of the road spike.

8. The multifunctional track pad according to claim 1, characterized in that, The minimum width Lm of the connection area between the basic units (14) satisfies: 0.1mm ≤ Lm ≤ 0.5mm.

9. The multifunctional track pad according to claim 1, characterized in that, The gasket body is made of a high-molecular elastic material and is integrally molded.

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