An under-track pad for a railway track

Abstract

The present application relates to the technical field of rail pad, and discloses a rail pad for rail, which comprises a plate body, a positioning edge for clamping on both sides of a sleeper and a buffer edge perpendicular to the positioning edge are arranged on the plate body, and the plate body is divided into a first contact surface close to a rail and a second contact surface close to the sleeper in the installed state; the buffer edge is an integral structure with the plate body, the buffer edge is located above the sleeper, the bottom of the buffer edge is parallel to the bottom of the plate body, the top of the buffer edge is provided with an inclined edge, and the inclined edge is in a rising trend from the side far away from the plate body to the side close to the plate body; and the pad is attached to the first contact surface of the plate body. In the present application, the buffer edge and the acute angle edge form a stress buffering effect at the contact position of the pad and the sleeper, the concentrated shear stress is dispersed through the buffer edge and the acute angle edge at the position where the concentrated shear stress is easily generated, the clear stress boundary where the shear is easily generated is blurred, the gnawing of the pad on the sleeper is reduced, and the service life of the sleeper is improved.

Description

Technical Field

[0001] This invention relates to the technical field of rail pads, and more specifically to a rail pad for railway tracks. Background Technology

[0002] Rail pads are a key component in railway track structures, and their core function is to provide elasticity to the rails. The existing rail pads are mainly of two types: ordinary rubber pads and thermosetting pads. Rubber pads are low in cost and have mature manufacturing processes, but their short service life has led to their gradual replacement by thermosetting pads with more stable performance.

[0003] Thermosetting pads effectively solve the problems of frequent replacements and short service life in harsh environments caused by the failure of rubber pads. Thermosetting elastomer pads, made from elastomeric materials, have higher elasticity. Furthermore, structural features such as grooves on the thermosetting elastomer pads not only reduce the weight and material consumption of the pads but also further enhance their elasticity. The grooves also further strengthen the friction between the pad and the sleeper / rail, preventing the pad from slipping off the sleeper.

[0004] However, grooved thermosetting elastomer pads can exacerbate the erosion of the sleepers by the pads, easily damaging the sleepers. Summary of the Invention

[0005] The purpose of this invention is to provide a rail pad for railway tracks, which can effectively improve the service life of the rail pad and reduce the wear of the pad on the sleepers.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following solution: A rail pad for railway tracks is provided, comprising a plate body, a positioning edge on the plate body for engaging with both sides of a sleeper, and a buffer edge perpendicular to the positioning edge. In the installed state, the plate body is divided into a first contact surface near the rail side and a second contact surface near the sleeper side. The buffer edge is an integral structure with the plate body, located above the sleeper, with its bottom parallel to the bottom of the plate body and its top having an inclined edge that rises from the side away from the plate body to the side near the plate body. It also includes a gasket attached to the first contact surface on the plate body.

[0007] The area most prone to friction and sleeper wear between the pad and the sleeper is located at the edge of the pad. When a train passes over the pad, the train's weight compresses the rail, and the rail transfers the force to the pad. In traditional designs, the side plane of the pad is perpendicular to the upper surface of the sleeper, resulting in a direct vertical transmission of the force from the train to the pad. This direct vertical transmission creates a shearing effect at the edge, exacerbating wear. This design incorporates a buffer edge at the contact point between the pad and the sleeper. The buffer edge disperses the force at the contact point, preventing excessive load on the sleeper and thus reducing sleeper wear.

[0008] As a preferred embodiment of the present invention, the second contact surface is provided with a plurality of bottom annular grooves of different diameters, the plurality of bottom annular grooves being concentric circles, the edge of the bottom annular groove being an acute-angled side structure facing the center of the groove, the bottom of the acute-angled side being parallel to the bottom of the plate, and the top of the acute-angled side being a bevel.

[0009] As a preferred embodiment of the present invention, the positioning edge is a trapezoidal prism structure protruding on both sides of the plate, which can quickly engage with the sleeper to complete the installation and positioning of the pad during installation.

[0010] As a preferred embodiment of the present invention, an assembly groove is provided on the plate near the two positioning edges, and an assembly edge is fixed on the side of the gasket near the assembly groove.

[0011] As a preferred embodiment of the present invention, the second contact surface is provided with a plurality of bottom annular grooves of different diameters, and the plurality of bottom annular grooves are concentric circles.

[0012] As a preferred embodiment of the present invention, the first contact surface is provided with a first top annular groove and a second top annular groove, the first top annular groove and the second top annular groove are concentric, and at the same time, the bottom annular groove provided at the position of the second contact surface is offset from the first top annular groove and the second top annular groove on the entire plate.

[0013] As a preferred embodiment of the present invention, the contact edge between the bottom annular groove and the sleeper is an acute-angled edge structure facing the center of the groove, the bottom of the acute-angled edge is parallel to the bottom of the plate, and the top of the acute-angled edge is a bevel.

[0014] As a preferred embodiment of the present invention, both the first and second top annular grooves are provided with rubber damping rings. The rubber damping rings include an arc-shaped extrusion side that protrudes from the top annular groove under normal conditions, and the arc-shaped extrusion side is located on the side of the pad closer to the rail.

[0015] As a preferred embodiment of the present invention, the plate is made of polyurethane as the pad material, the gasket is made of aluminum alloy, and the first contact surface of the pad is provided with a plurality of recessed holes. The walls of the recessed holes are uniformly arranged with a plurality of arc-shaped protrusions. On the gasket, a plurality of round bosses that fit the recessed holes are distributed on the side near the pad. After the pad and the gasket are attached, the round bosses are located in the recessed holes, and the sidewalls of the round bosses are in close contact with the arc-shaped protrusions.

[0016] By utilizing the material properties of the gasket and the pad, metal materials have a small coefficient of thermal deformation, while polyurethane plastics have a significantly larger coefficient of thermal deformation than metals. At low temperatures, the pad not only loses elasticity but also shrinks. In cold conditions, the shrinkage rate of metal is significantly less than that of plastic. After the plastic pad shrinks, the shrinkage force is transferred to the pad through the cooperation of the concave holes and the round bosses. The rubber damping ring supports the middle position of the pad, giving the pad a certain tendency to bend towards the rail side. This creates a prestress on the pad that bulges towards the rail side. This prestress can, to some extent, compensate for the elasticity loss of the pad caused by the temperature drop, ensuring the normal use of the pad in cold winters.

[0017] As a preferred embodiment of the present invention, the thickness of the gasket is in the range of 2-4 mm.

[0018] The beneficial effects of this invention are as follows: In this invention, at the contact point between the pad and the sleeper, a buffering effect is formed by the structure of the buffer edge and the acute angle edge. In the location where concentrated shear force is likely to occur, the concentrated shear force is dispersed by the buffer edge and the acute angle edge, blurring the clear force boundary that is prone to shear, reducing the wear of the pad on the sleeper, and improving the service life of the sleeper. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the present invention in use; Figure 2 This is a schematic diagram of the structure of the present invention; Figure 3 This is a structural diagram showing the pad and gasket in their unfolded state. Figure 4 This is a schematic diagram of the plate structure in this invention; Figure 5 This is a top view of the present invention; Figure 6 for Figure 5 Sectional view at point AA; Figure 7 for Figure 5 Sectional view at point BB; Figure 8 for Figure 5 Sectional view at CC; Figure 9 for Figure 7 Enlarged view of point D in the middle.

[0020] Reference numerals: 1-pad, 101-plate body, 102-positioning edge, 103-buffer edge, 104-bottom annular groove, 105-first top annular groove, 106-second top annular groove, 107-cavity, 108-hole, 109-arc-shaped protrusion, 1010-acute-angle edge, 2-shield, 201-sheet body, 202-locking edge, 203-circular boss, 3-rubber shock absorber ring. Detailed Implementation

[0021] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0022] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "longitudinal," "lateral," "horizontal," "inner," "outer," "front," "rear," "top," and "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0023] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set up," "have," "install," "connect," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0024] Example, reference Figure 1-9A rail pad for railway tracks includes a pad 1 and a pad 2. The pad 1 includes a plate body 101, with positioning edges 102 that engage with both sides of a sleeper and buffer edges 103 perpendicular to the positioning edges 102. In the installed state, the plate body 101 has a first contact surface near the rail side and a second contact surface near the sleeper side. The positioning edges 102 are trapezoidal prismatic structures protruding on both sides of the plate body 101, which can quickly engage with the sleeper to complete the installation and positioning of the pad 1. Buffer edges 103 are provided on the other two sides of the plate body 101. The buffer edges 103 are integral with the plate body 101 and are located above the sleeper. Parallel to the bottom of the plate 101, the top is provided with a sloping edge. This sloping edge rises from the side away from the plate 101 to the side closer to the plate 101. When the train runs over the pad 1, the rail is squeezed by the weight of the train. The closer the buffer edge 103 is to the plate 101, the greater the downward pressure on the sleeper. Traditional pads have a clear linear decreasing trend in pressure on the sleeper on the buffer edge 103. Through the structural design of the buffer edge 103, the force on the contact edge between the edge of the pad 1 and the sleeper is blurred. Thus, when the train runs over the area above the pad 1, the clear boundary features that are prone to shearing are blurred, reducing the wear of the pad 1 on the sleeper and increasing the service life of the sleeper.

[0025] The gasket 2 includes a sheet body 201, which is attached to the first contact surface on the plate body 101. In the installation state, it is placed between the rail and the rail pad 1. On the plate body 101, an assembly groove is provided on the side near the two positioning edges 102. The gasket 2 is fixedly provided with an assembly edge on the side near the assembly groove, which facilitates the quick assembly between the pad 1 and the gasket 2 when the rail pad 1 is installed under the rail.

[0026] In this embodiment, the second contact surface is provided with a plurality of bottom annular grooves 104 of different diameters. The plurality of bottom annular grooves 104 are concentric circles. The contact edge between the bottom annular groove 104 and the sleeper is an acute-angled edge 1010 structure facing the center of the groove. The bottom of the acute-angled edge 1010 is parallel to the bottom of the plate 101, and the top of the acute-angled edge 1010 is a bevel. The contact between the bottom annular groove 104 and the sleeper increases the friction between the sleeper and the bottom annular groove 104. At the same time, the structure of the acute-angled edge 1010 also changes the contact state between the edge of the annular groove and the sleeper from a clear boundary force contact to a vague force contact state. Thus, there is no longer a clear force shear edge at the contact position between the plate 101 and the sleeper, which greatly reduces the biting effect of the pad 1 on the sleeper.

[0027] In this embodiment, a first top annular groove 105 and a second top annular groove 106 are provided on the first contact surface. The first top annular groove 105 and the second top annular groove 106 are concentric. Meanwhile, the bottom annular groove 104 provided at the position of the second contact surface is staggered with the first top annular groove 105 and the second top annular groove 106 on the entire plate 101. The structure of the annular groove improves the elastic performance of the plate 101.

[0028] Furthermore, both the first top annular groove 105 and the second top annular groove 106 are provided with rubber shock-absorbing rings 3. The rubber shock-absorbing ring 3 includes an arc-shaped extrusion side that protrudes from the top annular groove under normal conditions. This arc-shaped extrusion side is located on the side of the pad 1 closest to the rail. The shock-absorbing effect of the pad 1 is further enhanced by the cooperation of the pad 2 and the rubber shock-absorbing ring 3. A cavity 107 is provided in the middle area of ​​the second top annular groove 106. The cavity 107 cooperates with the pad 2. After some of the gas in the cavity 107 is squeezed out, the cavity 107 can make the pad 1 and the pad 2 tightly adhered, increasing the tight connection between the pad 1 and the pad 2.

[0029] It should be noted that after the temperature drops in winter, the elastic properties of the pad 1 will decrease and its brittleness will increase due to thermal expansion and contraction and the brittleness of the pad 1 in the cold environment. This problem exists for both rubber pad 1 and thermosetting pad 1.

[0030] In this embodiment, to reduce the aforementioned impact, the plate 101 is made of a thermosetting material, preferably polyurethane, and the gasket 2 is made of aluminum alloy. The first contact surface of the plate 1 has multiple recesses 108, and the walls of the recesses 108 are uniformly arranged with multiple arc-shaped protrusions 109. On the sheet 201 of the gasket 2, near the side of the plate 1, multiple round bosses 203 adapted to the recesses 108 are distributed. After the plate 1 and gasket 2 are attached, the round bosses 203 are located within the recesses 108, and the sidewalls of the round bosses 203 are in close contact with the arc-shaped protrusions 109. At low temperatures, the deformation of the plastic plate 1 during cold contraction is significantly greater than that of the metal gasket 2. (Refer to...) Figure 8 At low temperatures, the shrinkage of plate 101 in the vertical direction is significantly greater than that of sheet 201. The compressed rubber damping ring 3 provides a rightward thrust to sheet 201. At low temperatures, the pad 2 is affected by the low temperature of pad 1 and tends to arch towards the rail side, thus creating a prestress effect. After the pad 1 is cooled, it shrinks as a whole. The volume of the first top annular groove 105 and the second top annular groove 106 where the rubber damping ring 3 is installed will also shrink to a certain extent, causing the rubber damping ring 3 to be squeezed. This increases the support force on the pad 2, which can compensate for the elastic loss and reduced damping performance caused by the shrinkage of the pad 1 due to low temperature, and reduce the elastic loss in cold environments.

[0031] Furthermore, the thickness of the shim 2 ranges from 2 to 4 mm, specifically including various specifications such as 2 mm, 3 mm, and 4 mm. When used in the sunken area of ​​the sleeper or on some sleepers that have been worn to a certain extent, the height of the rail can be leveled by replacing the shim 2 with a thicker one. The shim 2 can be replaced according to different degrees of wear, so that the sleeper can be used for a longer period of time.

[0032] Furthermore, regularly distributed mesh holes are formed on the pad plate, utilizing the deformation space of the perforated structure to compensate for the increased stiffness of the material at low temperatures. The mesh structure allows the pad plate to maintain a certain deformation capacity at low temperatures, mitigating the tendency for dynamic stiffness and damping coefficient to increase sharply with decreasing temperature. Together with the bottom annular groove 104, the first top annular groove 105, and the second top annular groove 106, it forms a spatially interwoven elastic compensation network. The grooves on the upper and lower surfaces, along with the internal mesh holes, constitute a multi-dimensional deformation space.

[0033] Advantageously, a stiffness gradient is established along the thickness direction of the pad, with a lower stiffness material layer used near the rail and a higher stiffness material layer used near the sleeper. At low temperatures, the lower stiffness layer maintains relatively good elasticity, while the higher stiffness layer provides structural support.

[0034] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Based on the technical essence of the present invention, any simple modifications, equivalent substitutions, and improvements made to the above embodiments within the spirit and principles of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A rail pad for railway tracks, comprising a pad (1) and a shim (2), characterized in that, The pad (1) includes a plate body (101), and the plate body (101) is provided with a positioning edge (102) that engages with both sides of the sleeper and a buffer edge (103) perpendicular to the positioning edge (102). In the installed state, the plate body (101) is divided into a first contact surface near the rail side and a second contact surface near the sleeper side. The buffer edge (103) and the plate (101) are an integral structure. The buffer edge (103) is located above the sleeper. The bottom of the buffer edge (103) is parallel to the bottom of the plate (101). The top is provided with an inclined edge. The inclined edge rises from the side away from the plate (101) to the side close to the plate (101). The gasket (2) is attached to the first contact surface of the plate (101).

2. A rail pad for railway tracks according to claim 1, characterized in that, The second contact surface is provided with a plurality of bottom annular grooves (104) of different diameters. The plurality of bottom annular grooves (104) are concentric circles. The edge of the bottom annular groove (104) is an acute angle edge (1010) structure facing the center of the groove. The bottom of the acute angle edge (1010) is parallel to the bottom of the plate (101), and the top of the acute angle edge (1010) is a bevel.

3. A rail pad for railway tracks according to claim 1, characterized in that, The positioning edge (102) is a trapezoidal prism structure protruding on both sides of the plate (101), which can quickly engage with the sleeper to complete the installation and positioning of the pad (1) when installing the pad (1).

4. A rail pad for railway tracks according to claim 1, characterized in that, On the plate (101), there is an assembly groove near the two positioning edges (102), and the gasket (2) is fixed with an assembly edge near the side of the assembly groove.

5. A rail pad for railway tracks according to claim 1, characterized in that, The second contact surface is provided with multiple bottom annular grooves (104) of different diameters, and the multiple bottom annular grooves (104) are concentric circles.

6. A rail pad for railway tracks according to claim 5, characterized in that, The first contact surface is provided with a first top annular groove (105) and a second top annular groove (106), the first top annular groove (105) and the second top annular groove (106) are concentric, and the bottom annular groove (104) provided at the position of the second contact surface is offset from the first top annular groove (105) and the second top annular groove (106) on the entire plate (101).

7. A rail pad for railway tracks according to claim 5, characterized in that, The contact edge between the bottom annular groove (104) and the sleeper is an acute-angled edge (1010) structure facing the center of the groove. The bottom of the acute-angled edge (1010) is parallel to the bottom of the plate (101), and the top of the acute-angled edge (1010) is a bevel.

8. A rail pad for railway tracks according to claim 6, characterized in that, Both the first top annular groove (105) and the second top annular groove (106) are provided with rubber damping rings (3). The rubber damping rings (3) include an arc-shaped extrusion side that protrudes from the top annular groove under normal conditions. The arc-shaped extrusion side is located on the pad (1) on the side closer to the rail.

9. A rail pad for railway tracks according to claim 1, characterized in that, The plate (101) is made of polyurethane as the material of the pad (1), and the gasket (2) is made of aluminum alloy. The first contact surface of the pad (1) is provided with a plurality of recesses (108). The walls of the recesses (108) are uniformly arranged with a plurality of arc-shaped protrusions (109). On the plate (201) of the gasket (2), a plurality of round bosses (203) that are adapted to the recesses (108) are distributed on the side near the pad (1). After the pad (1) and the gasket (2) are attached, the round bosses (203) are located in the recesses (108), and the sidewalls of the round bosses (203) are in close contact with the arc-shaped protrusions (109).

10. A rail pad for railway tracks according to claim 1 or 9, characterized in that, The thickness of the gasket (2) ranges from 2 to 4 mm.

Images