Broadband energy consumption type rail fastener

Abstract

The present application relates to a kind of broadband energy consumption type rail fastener, the fastener includes track under composite sandwich leaf spring assembly and steel rail elastic restraint component, track under composite sandwich leaf spring assembly and steel rail elastic restraint component are fixed on sleeper, track under composite sandwich leaf spring assembly is located below steel rail, steel rail elastic restraint component is used to provide steel rail elastic restraint.Track under composite sandwich leaf spring assembly is composed of rail support, viscoelastic layer, damping alloy layer, leaf spring support, first anchoring bolt and positioning clamp, leaf spring support is fixed on sleeper by first anchoring bolt;Rail support, viscoelastic layer, damping alloy layer, leaf spring support are constrained by positioning clamp so that not large relative slip occurs, leading to track under composite sandwich leaf spring assembly overall structure eccentric failure.The present application can change the thickness, width or layer number of viscoelastic layer and damping alloy layer and the material of damping alloy layer to change carrying capacity and effective stroke, and it has good applicability for heavy load and light load railway.

Description

Technical Field

[0001] This invention belongs to the field of rail fastener technology, and in particular relates to a broadband energy-dissipating rail fastener. Background Technology

[0002] In recent years, as my country's urban rail transit has developed towards high speed, heavy load, and high density, the tense situation of urban traffic congestion has been alleviated. However, at the same time, the vibration and noise pollution generated has also increased significantly. Although the problem of vibration and noise pollution in urban rail transit has been effectively controlled through structures such as steel spring floating plates, rail dampers, sound barriers, and fasteners, especially the widespread application of high-grade vibration isolation fasteners, which effectively isolates most of the medium and high frequency vibration energy and greatly improves the vibration and noise problem along the track; however, most of the existing vibration isolation fasteners use rubber-based viscoelastic materials as the main elastic element, and the entire fastener system plays a role in vibration isolation rather than energy dissipation.

[0003] From the perspective of vibration isolation, vibration energy in the vibration isolation frequency range can only be more effectively isolated when the material damping is limited. However, the dynamic-static stiffness ratio of existing fasteners has an upper limit, and the vibration energy that is effectively isolated cannot be dissipated in a timely and effective manner. Meanwhile, the low-frequency vibration energy in the non-vibration isolation frequency range is amplified and transmitted to the area below the fastener node and even to the vibration environment along the line.

[0004] From an energy dissipation perspective, the limited material damping designed to ensure mid-to-high frequency vibration isolation inherently limits the energy dissipation efficiency of the fastening system. Furthermore, when vibrations with a high frequency component are transmitted from the wheel-rail coupling system to the fastening nodes, existing fasteners often exhibit excessive frequency-dependent dynamic stiffness, resulting in only a small dynamic response amplitude under high-frequency excitation, thus leading to poor energy dissipation.

[0005] In summary, existing fasteners all suffer from insufficient energy dissipation despite adequate vibration isolation, easily leading to a series of vibration and noise problems in the track substructure, the surrounding environment, and various track subsystems and the vehicle body. The main load-bearing components of rail transit are constantly subjected to a broadband forced vibration environment, dominated by low frequencies with a significant presence of mid-to-high frequency components. Matching the static stiffness, dynamic stiffness, or rebound characteristics (i.e., damping characteristics) of rubber-based elastic elements has become a design challenge. Therefore, designing a high-performance broadband energy-dissipating track fastener is a problem urgently needing to be solved by those skilled in the art. Summary of the Invention

[0006] Given that existing fasteners often suffer from insufficient energy dissipation despite adequate vibration isolation, this invention provides a wideband energy-dissipating track fastener.

[0007] The objective of this invention can be achieved through the following technical solutions:

[0008] This invention provides a broadband energy-dissipating track fastener, which includes a rail-mounted composite sandwich leaf spring assembly and a rail elastic constraint assembly. Both the rail-mounted composite sandwich leaf spring assembly and the rail elastic constraint assembly are fixed on the sleeper. The rail-mounted composite sandwich leaf spring assembly is located below the rail, and the rail elastic constraint assembly is used to provide elastic constraint for the rail.

[0009] In some embodiments of the present invention, the rail-mounted composite sandwich leaf spring assembly consists of a rail support, a viscoelastic layer, a damping alloy layer, a leaf spring support, a first anchor bolt, and a positioning clamp, wherein the leaf spring support is fixed to the sleeper by the first anchor bolt.

[0010] The rail support, viscoelastic layer, damping alloy layer, and leaf spring support are constrained by positioning clamps to prevent large relative slippage that could lead to eccentric failure of the overall structure of the composite sandwich leaf spring assembly under the rail.

[0011] In some embodiments of the present invention, the viscoelastic layer and the damping alloy layer are arranged in a layer-by-layer manner, i.e., in the form of "viscoelastic layer-damping alloy layer-viscoelastic layer-damping alloy layer...", and the length of each "viscoelastic layer-damping alloy layer" structure decreases from top to bottom.

[0012] In some embodiments of the present invention, the rail support, leaf spring support, and positioning clamp are all made of spring steel.

[0013] In some embodiments of the present invention, the overall material of the viscoelastic layer is a high molecular polymer; each viscoelastic layer and damping alloy layer has a very small thickness ratio and the bending curvature is consistent, all being an upwardly curved U-shaped configuration.

[0014] In some embodiments of the present invention, the damping alloy layer is made of alloy materials with different damping and energy dissipation mechanisms, such as high-manganese-based damping alloys, multiphase damping alloys, dislocation damping alloys, ferromagnetic damping alloys, or Fe-Mn-based damping alloys. The material, thickness, width, or number of layers of the damping alloy layer is matched and designed according to different train operating conditions, making it highly applicable to effective load bearing, vibration isolation, and energy dissipation under various complex operating conditions such as high-speed, heavy-load, high-density, and small-radius curved tracks.

[0015] In some embodiments of the present invention, the rail support, viscoelastic layer, damping alloy layer, and leaf spring support are constrained by a number of pairs of positioning clamps; the joints of each pair of positioning clamps are connected by welding.

[0016] In some embodiments of the present invention, the first anchor bolt consists of a first bolt, a first spring washer, and a first flat washer.

[0017] In some embodiments of the present invention, the rail elastic constraint assembly consists of an elastic bar, a constraint support, an insulating gauge block, and a second anchor bolt, wherein the constraint support is fixed to the sleeper by the second anchor bolt.

[0018] The elastic bar has an initial upward elastic deformation at the end that contacts the insulated gauge block to ensure sufficient clamping force on the rail when the train passes.

[0019] In some embodiments of the present invention, the second anchor bolt consists of a second bolt, a second spring washer, and a second flat washer.

[0020] The broadband energy-consuming track fastener provided by this invention has two operating states under different working conditions:

[0021] When no train is passing, the two ends of the rail support are in a state of natural downward slight bending under the influence of the clamping pressure and the weight of the rail, and are in contact with the lower surface of the rail.

[0022] When a train passes, the rails generate broadband vibrations. These vibrations cause the composite sandwich leaf spring assembly beneath the rails to undergo repeated vertical bending motions. This causes the damping alloy layer to repeatedly bend and deform under alternating loads, thus dissipating energy. Although the energy dissipation mechanisms of different damping alloys are not entirely the same (e.g., twinned, ferromagnetic, dislocation-type, Fe-Mn based damping alloys), they generally possess advantages such as high strength, good resilience, and a high loss factor within the elastic range. The viscoelastic layer undergoes repeated compression deformation under alternating loads, dissipating energy due to the internal friction effect of the material. Furthermore, under alternating loads, external friction occurs between the viscoelastic layer and the damping alloy layer, further dissipating energy. The combined effect of these three energy dissipation mechanisms ensures that the broadband vibrations generated by the rails are dissipated in a timely manner.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] 1. Wideband energy dissipation capability: Due to the use of a composite sandwich leaf spring assembly with alternating layers of viscoelastic and damping alloy layers under the rail, which replaces the traditional rail rubber pad (viscoelastic material) of fasteners, the dynamic stiffness does not increase significantly with frequency under high-frequency loads or high-frequency excitation conditions, solving the problem of untimely rebound of traditional fasteners, thus providing a more effective wideband energy dissipation effect.

[0025] II. Combining vibration isolation and wide-frequency energy dissipation effects: Through the design of the viscoelastic layer material and thickness, as well as the geometric design of the entire composite sandwich leaf spring assembly, this new type of fastener has similar static stiffness, ensuring the vibration isolation level; the damping alloy layer dissipates the vibration energy in a wide frequency range, including rails, car bodies, etc., improving or solving the technical status quo of existing products that are sufficient for vibration isolation but insufficient for energy dissipation.

[0026] III. Safety and Reliability: Due to the high stiffness of the composite sandwich leaf spring assembly under the rail, and the maximum downward bending deformation being much smaller than the effective stroke of the leaf spring, the entire rail system is guaranteed not to fail under extreme environments.

[0027] IV. Wide range of applications: The load-bearing capacity and effective stroke can be changed by altering the thickness, width, or number of viscoelastic and damping alloy layers, as well as the material of the damping alloy layer, making it highly applicable to both heavy-load and light-load railways. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the broadband energy-dissipating track fastener in Embodiment 1 of the present invention;

[0029] Figure 2 This is a schematic diagram of the structure of the composite sandwich leaf spring assembly under the rail in Embodiment 1 of the present invention;

[0030] Figure 3 This is a front view of the composite sandwich leaf spring assembly under the rail in Embodiment 1 of the present invention.

[0031] Figure 4 This is a schematic diagram of the installation of the composite sandwich leaf spring assembly under the rail in Embodiment 1 of the present invention;

[0032] Figure 5 This is a schematic diagram of the elastic constraint component for the rail in Embodiment 1 of the present invention.

[0033] The numbers in the diagram are as follows:

[0034] 1. Rail-mounted composite sandwich leaf spring assembly; 2. Rail elastic constraint assembly; 1-1. Rail support; 1-2. Viscoelastic layer; 1-3. Damping alloy layer; 1-4. Leaf spring support; 1-5. First anchor bolt; 1-6. Positioning clamp; 1-5-1. First bolt; 1-5-2. First spring washer; 1-5-3. First flat washer; 2-1. Elastic strip; 2-2. Constraint support; 2-3. Insulated gauge block; 2-4. Second bolt; 2-5. Second spring washer; 2-6. Second flat washer. Detailed Implementation

[0035] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0036] Example 1

[0037] refer to Figures 1-5 This embodiment provides a broadband energy-consuming track fastener, which includes a rail-mounted composite sandwich leaf spring assembly 1 and a rail elastic constraint assembly 2. Both the rail-mounted composite sandwich leaf spring assembly 1 and the rail elastic constraint assembly 2 are fixed on the sleeper. The rail-mounted composite sandwich leaf spring assembly 1 is located below the rail, and the rail elastic constraint assembly 2 is used to provide elastic constraint for the rail.

[0038] In this embodiment, the rail-supported composite sandwich leaf spring assembly 1 consists of a rail support 1-1, a viscoelastic layer 1-2, a damping alloy layer 1-3, a leaf spring support 1-4, a first anchor bolt 1-5, and a positioning clamp 1-6. The leaf spring support 1-4 is fixed to the sleeper by the first anchor bolt 1-5. The rail support 1-1, viscoelastic layer 1-2, damping alloy layer 1-3, and leaf spring support 1-4 are constrained by the positioning clamp 1-6 to prevent large relative slippage that could lead to eccentric failure of the overall structure of the rail-supported composite sandwich leaf spring assembly. The viscoelastic layer 1-2 and the damping alloy layer 1-3 are arranged in an alternating layer configuration, i.e., a "viscoelastic layer-damping alloy layer-viscoelastic layer-damping alloy layer..." pattern, with the length of each "viscoelastic layer-damping alloy layer" structure decreasing from top to bottom. The rail support 1-1, leaf spring support 1-4, and positioning clamp 1-6 are all made of spring steel. The viscoelastic layer 1-2 is made of a high molecular polymer. Each viscoelastic layer 1-2 and damping alloy layer 1-3 has a very small thickness ratio and the bending curvature is consistent, both being U-shaped with upward bending.

[0039] In this embodiment, the damping alloy layers 1-3 are made of high-manganese-based damping alloys. In other embodiments, alloy materials with different damping and energy dissipation mechanisms, such as multiphase damping alloys, dislocation damping alloys, ferromagnetic damping alloys, or Fe-Mn-based damping alloys, can also be selected. The material, thickness, width, or number of layers of the damping alloy layers is matched according to different train operating conditions, making it highly applicable to effective load bearing, vibration isolation, and energy dissipation under various complex conditions such as high-speed, heavy-load, high-density, and small-radius curved tracks.

[0040] In this embodiment, the rail support 1-1, viscoelastic layer 1-2, damping alloy layer 1-3, and leaf spring support 1-4 are constrained by several pairs of positioning clamps 1-6; the joints of each pair of positioning clamps 1-6 are connected by welding. The first anchor bolt 1-5 consists of a first bolt 1-5-1, a first spring washer 1-5-2, and a first flat washer 1-5-3.

[0041] In this embodiment, the rail elastic constraint assembly 2 consists of a spring clip 2-1, a constraint support 2-2, an insulating gauge block 2-3, and a second anchor bolt. The constraint support 2-2 is fixed to the sleeper by the second anchor bolt. The end of the spring clip 2-1 that contacts the insulating gauge block 2-3 has an initial upward elastic deformation to ensure sufficient clamping force on the rail when the train passes. The second anchor bolt consists of a second bolt 2-4, a second spring washer 2-5, and a second flat washer 2-6.

[0042] The effective vertical deformation stroke of the under-rail composite sandwich leaf spring assembly 1 is much greater than the maximum downward bending deformation of the under-rail composite sandwich leaf spring assembly. The rail support 1-1 is in contact with the lower surface of the rail. When the train passes, the under-rail composite sandwich leaf spring assembly 1 generates broadband vibration. The vibration causes the under-rail composite sandwich leaf spring assembly 1 to undergo repeated vertical bending motion. This causes the damping alloy layer to repeatedly bend and deform under alternating loads, thereby dissipating energy. Although the energy dissipation mechanisms of different damping alloys are not entirely consistent, such as twinned, ferromagnetic, dislocation, and Fe-Mn based damping alloys, they generally have advantages such as high strength, good resilience, and high loss factor within the elastic range. The viscoelastic layer undergoes repeated compression deformation under alternating loads, dissipating energy due to the internal friction effect of the material. Under alternating loads, an external friction effect (Coulomb friction generated during the relative motion of the joint surface) is generated between the viscoelastic layer and the damping alloy layer. The external friction converts the mechanical energy of the vibration into heat energy, which is dissipated into the medium, thus dissipating energy. Due to the combined effect of the above three energy dissipation methods, the broadband vibration generated by the rail can be dissipated in a timely manner, ensuring the smooth operation of the train.

[0043] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A broadband energy-dissipating track fastener, characterized in that, The fastener includes a rail-mounted composite sandwich leaf spring assembly (1) and a rail elastic constraint assembly (2). Both the rail-mounted composite sandwich leaf spring assembly (1) and the rail elastic constraint assembly (2) are fixed on the sleeper. The rail-mounted composite sandwich leaf spring assembly (1) is located below the rail, and the rail elastic constraint assembly (2) is used to provide elastic constraint for the rail. The rail-mounted composite sandwich leaf spring assembly (1) consists of a rail support (1-1), a viscoelastic layer (1-2), a damping alloy layer (1-3), a leaf spring support (1-4), a first anchor bolt (1-5), and a positioning clamp (1-6). The leaf spring support (1-4) is fixed to the sleeper by the first anchor bolt (1-5). The rail support (1-1), viscoelastic layer (1-2), damping alloy layer (1-3), and leaf spring support (1-4) are constrained by positioning clamps (1-6) to prevent large relative slippage that could lead to eccentric failure of the overall structure of the composite sandwich leaf spring assembly under the rail. The viscoelastic layer (1-2) and the damping alloy layer (1-3) are arranged in a layer-by-layer manner, and the length of each "viscoelastic layer-damping alloy layer" structure decreases from top to bottom. The rail elastic constraint assembly (2) consists of an elastic bar (2-1), a constraint support (2-2), an insulating gauge block (2-3), and a second anchor bolt. The constraint support (2-2) is fixed to the sleeper by the second anchor bolt. The elastic bar (2-1) has an initial upward elastic deformation at the end that contacts the insulated gauge block (2-3) to ensure sufficient clamping force on the rail when the train passes.

2. The broadband energy-dissipating track fastener according to claim 1, characterized in that, The rail support (1-1), leaf spring support (1-4), and positioning clamp (1-6) are all made of spring steel.

3. A broadband energy-dissipating track fastener according to claim 1, characterized in that, The damping alloy layer (1-3) is made of high manganese-based damping alloy, multiphase damping alloy or dislocation damping alloy.

4. A broadband energy-dissipating track fastener according to claim 1, characterized in that, The rail support (1-1), viscoelastic layer (1-2), damping alloy layer (1-3), and leaf spring support (1-4) are constrained by several pairs of positioning clamps (1-6); the joints of each pair of positioning clamps (1-6) are connected by welding.

5. A broadband energy-dissipating track fastener according to claim 1, characterized in that, The first anchor bolt (1-5) consists of a first bolt (1-5-1), a first spring washer (1-5-2), and a first flat washer (1-5-3).

6. A broadband energy-dissipating track fastener according to claim 1, characterized in that, The second anchor bolt consists of a second bolt (2-4), a second spring washer (2-5), and a second flat washer (2-6).

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