An elastic pad

Abstract

The present invention discloses an elastic pad, including an upper end face in contact with a rail and a lower end face in contact with a sleeper, characterized in that first bearing bosses are arranged around the upper end face, a plurality of second bearing bosses are arranged between the first bearing bosses, a plurality of third bearing bosses are also arranged on the upper end face, the bearing areas of the first bearing bosses, the second bearing bosses and the third bearing bosses become smaller in sequence, and the heights of the first bearing bosses, the second bearing bosses and the third bearing bosses increase in sequence. In the present invention, a structural design is carried out for the elastic pad, and by optimizing the upper end face and combining the first bearing bosses, the second bearing bosses and the third bearing bosses of different heights and bearing areas, a free conversion between high stiffness and low stiffness can be achieved, and special working conditions such as no-load, half-load, full-load, heavy-load and eccentric load can be met.

Description

Technical Field

[0001] The invention belongs to the field of railway tracks, and in particular relates to an elastic pad. Background Art

[0002] Railway track engineering transportation has attracted the attention of railway transportation departments around the world due to its low pollution, low energy consumption, large transportation capacity, high efficiency and low transportation cost, especially in some countries with vast territory, rich resources, and a large proportion of bulk cargo transportation such as coal, oil and ore, such as Canada, the United States, Brazil and South Africa. Railway track engineering has developed rapidly around the world and has been internationally recognized as the development direction of railway freight. my country has a vast territory, uneven distribution of resources, and many resources need to be transported over long distances. Therefore, railway track engineering has a lot of development space and very broad application prospects in my country.

[0003] Under the long-term action of high-speed heavy-load trains or repeated motion loads, the roadbed or infrastructure of railway track engineering is prone to excessive powdering rate, whitening of the roadbed, severe compaction, and even liquefaction of the gate, which greatly increases the workload and cost of maintenance and repair, and seriously affects the safety and stability of driving. Although the sleepers have undergone innovations from wooden sleepers, concrete sleepers to steel sleepers, the wear on the sleeper rail surface when concrete sleepers are used in heavy-load lines with large axle weights is relatively serious. Steel sleepers have obvious advantages in reducing clearance and maintaining track gauge, but their teeth with the roadbed are quite difficult, and the cost is relatively high. The technical countermeasures of elastic pads to reduce track vibration and noise generated by heavy-load trains during operation and reduce track stiffness are recognized by the world as the simplest, most feasible and economical method. At present, due to the development of the rail transportation industry, the comprehensive performance of the traditional flat-plate elastic pads can no longer meet the requirements of the increase in the total weight and axle weight of heavy-load transport trains in the world and the continuous improvement of traction. Therefore, the development of new elastic pads with good comprehensive performance brings an effective solution to this problem.

[0004] Nowadays, more and more rubber elastic pads are used for shock absorption support of railway track projects. Nowadays, rubber pads for track projects are mostly made of styrene-butadiene rubber materials. The elastic pads for domestic railway track projects are mainly vulcanized and molded by styrene-butadiene rubber, and the upper and lower surfaces are designed with groove structures, which are formed by hot vulcanization of molds. Usually, manufacturers will open right-angle or arc grooves on the two surfaces that are combined with the track and the roadbed, and finally vulcanize them as a whole. The simplest groove, trapezoidal groove, and wavy shape structural design in structural design have the following problems: (1) Ordinary structural design, such as groove and wave design, is not very ideal and cannot meet the requirements of harsh surface conditions. (2) The structural design of the bottom surface of the product is simple and easy to slide sideways, resulting in product failure. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies and defects mentioned in the above background technology and provide an elastic pad with a long service life, which can meet the harsh environment and various complex working conditions. In order to solve the above technical problems, the technical solution proposed by the present invention is:

[0006] An elastic pad comprises an upper end face in contact with a rail and a lower end face in contact with a sleeper, characterized in that a first bearing boss is arranged around the upper end face (the position of the first bearing boss is based on ensuring full support of the edge of the rail), a plurality of second bearing bosses are arranged between the first bearing bosses, and a plurality of third bearing bosses are also arranged on the upper end face, the bearing areas of the first bearing boss, the second bearing boss and the third bearing boss become smaller in sequence, and the heights of the first bearing boss, the second bearing boss and the third bearing boss increase in sequence.

[0007] In the above-mentioned elastic pad, preferably, the cross-section of the first bearing boss is an ellipse or a rounded rectangle (the shape of the rectangle after rounding is similar to a circle or an ellipse), and the longitudinal sections relative to the long axis of the first bearing boss are parallel to each other. More preferably, considering the elasticity of the structure, the characteristics of the track and the anti-climbing performance, the cross-section of the above-mentioned first bearing boss is an ellipse. The above-mentioned cross-section is parallel to the upper end face. When the cross-section of the first bearing boss is an ellipse, the long axis longitudinal section refers to the longitudinal section at the long axis of the ellipse, and the longitudinal section is perpendicular to the upper end face. When the cross-section of the first bearing boss is a rounded rectangle, the long axis longitudinal section refers to the longitudinal section parallel to the long side of the rounded rectangle, and the longitudinal section is perpendicular to the upper end face and parallel to the long side of the rounded rectangle. In the present invention, the meanings of the cross section and the long axis longitudinal section in this article are the same as here.

[0008] In the above-mentioned elastic pad, preferably, the cross-section of the second bearing boss is an ellipse or a rounded rectangle (the shape of the rectangle after rounding is similar to a circle or an ellipse), the long-axis longitudinal sections of the plurality of the second bearing bosses are parallel to each other, and the long-axis longitudinal sections of the second bearing bosses are perpendicular to the direction of travel of the rail. More preferably, considering the elasticity of the structure, the characteristics of the track and the anti-climbing performance, the cross-section of the above-mentioned second bearing boss is an ellipse. In addition, the long-axis longitudinal section of the above-mentioned second bearing boss is perpendicular to the direction of travel of the rail, which can resist the impact of braking and starting of the train and uphill and downhill, and the design is more reasonable.

[0009] In the above elastic pad, preferably, the cross-section of the third bearing boss is circular, elliptical or square with rounded corners.

[0010] In the elastic pad, preferably, the lower end surface is provided with a plurality of concave holes of different sizes. The area of ​​the plurality of concave holes is adjusted according to the size of each bearing boss, mainly to ensure that elastic deformation can be generated under the bearing stiffness.

[0011] In the above-mentioned elastic pad, preferably, a row of concave circular holes are provided on the intersection line of the long axis longitudinal section and the lower end face of the first bearing boss and the second bearing boss. More preferably, the concave circular hole corresponding to the center bottom of the first bearing boss is the largest, and the concave circular holes on both sides of the largest concave circular hole gradually become smaller in sequence (here refers to the distribution of a row of concave circular holes at the bottom of the first bearing boss); the concave circular hole corresponding to the center bottom of the second bearing boss is the largest, and the concave circular holes on both sides of the largest concave circular hole gradually become smaller in sequence (here refers to the distribution of a row of concave circular holes at the bottom of the second bearing boss). The concave circular holes on the lower end face of the elastic pad are related to the diameter and size of the corresponding bosses. This setting can make the product cross-section produce an equal structural thickness, so that the stiffness presents a stepped elastic deformation and compression. In addition, the above-mentioned design has the anti-climbing property of a bionic suction cup.

[0012] In the above elastic pad, preferably, the first bearing boss occupies 35-43% of the area of ​​the upper end surface, the second bearing boss occupies 25-30% of the area of ​​the upper end surface, and the third bearing boss occupies 15-20% of the area of ​​the upper end surface. The load size determines the size and range of the bearing boss. The greater the load, the more contact surfaces and the greater the stiffness. The above bearing areas can provide different stiffness ranges to suit different load conditions.

[0013] In the above elastic pad, preferably, the height difference between the first bearing boss and the second bearing boss is 0.2-2mm, and the height difference between the second bearing boss and the third bearing boss is 0.2-2mm. The above height difference has a very important influence on the function of the elastic pad of the present invention. If the height difference is too large, the transition time of the structural stiffness is long, which cannot meet the heavy load of the railway and the road conditions and operation changes of the track. If the height difference is too small, it is difficult to meet the requirements of multi-level bearing.

[0014] The raw materials of the elastic pad include TPE, anti-ultraviolet sunscreen, chain extender, antioxidant, reinforcing agent, etc. It is prepared by injection molding, and the specific steps include the following steps: filling, pressure holding, cooling, and demoulding. The mold in the above preparation process adopts a hemp pattern design to avoid the shrinkage of the product from having a greater impact on the size.

[0015] In the above preparation method, the crystallization temperature of the mixed material before filling is 150-155°C, the softening degree is 185°C, the melting point is 210°C, the baking temperature is 130°C, and it is maintained for 130-200 minutes. The process temperature during filling is 210-240°C, the injection pressure during the holding stage is 120-130MPa, the holding time is 28±2s, and the holding pressure is 110-120MPa.

[0016] In the present invention, the elastic pad is structurally designed. By optimizing the upper end surface and combining the first bearing boss, the second bearing boss and the third bearing boss of different heights and different bearing areas, the free conversion between large stiffness and small stiffness can be realized to meet the special working conditions such as no-load, half-load, full load, heavy load and eccentric load. The impacts on the rail and the pad caused by serpentine turning, tilting, uphill and downhill, start and stop, etc., the large impact under heavy load is jointly carried out by the first bearing boss, the second bearing boss and the third bearing boss for bearing and shock absorption, and the third bearing boss (and the second bearing boss) is used for bearing and shock absorption under small stiffness. By optimizing the lower end surface and adopting the design of concave circular holes of different sizes, the contact surface with the sleeper is a large plane, which avoids gnawing on the sleeper and realizes the elastic deformation of the elastomer at the same time. The suction cup design is adopted based on the concept of animal bionics, which can well adsorb the sleeper and prevent the elastic pad from sliding out, so as to achieve good shock absorption and support effects.

[0017] Compared with the prior art, the advantages of the present invention are:

[0018] 1. The present invention carries out structural design on the upper end surface of the elastic pad. The upper end surface adopts a combination of the first bearing boss, the second bearing boss and the third bearing boss, and the lower end surface adopts a concave circular hole design. When unloaded, it is mainly supported by the third bearing boss. When starting and stopping, going up and down slopes, etc., it is mainly supported by the front and rear first bearing bosses. When the train turns and is overloaded, it is mainly supported by the second bearing boss and the first bearing bosses on both sides. The requirements of various complex working conditions are met, and the shock absorption and support effects are good. It can be applied to the shock absorption and heavy load resistant elastic shock absorption support required for high-speed railways, track projects or various projects.

[0019] 2. The lower end surface of the present invention adopts a concave circular hole design of varying sizes, and adopts the concept of animal bionics to carry out a suction cup design to prevent the elastic pad from sliding out, thereby achieving a good effect of shock absorption and support. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 This is a schematic diagram of the front structure of the elastic pad in Example 1.

[0022] Figure 2 This is a schematic diagram of the back structure of the elastic pad in Example 1.

[0023] Figure 3This is a top view of the elastic pad in Example 1.

[0024] Figure 4 This is a bottom view of the elastic pad in Example 1.

[0025] Figure 5 This is a schematic diagram of the front structure of the elastic pad in Example 2.

[0026] Legend:

[0027] 1. Upper end surface; 2. Lower end surface; 3. First bearing boss; 4. Second bearing boss; 5. Third bearing boss; 6. Concave circular hole. DETAILED DESCRIPTION

[0028] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively and meticulously below in conjunction with the accompanying drawings and preferred embodiments of the present invention, but the protection scope of the present invention is not limited to the following specific embodiments.

[0029] Unless otherwise defined, all the professional terms used below have the same meanings as those generally understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention.

[0030] Embodiment 1:

[0031] like Figure 1-Figure 4 As shown, the elastic pad of this embodiment includes an upper end face 1 in contact with the rail and a lower end face 2 in contact with the sleeper, four first bearing bosses 3 are provided at the four edges of the upper end face 1, four second bearing bosses 4 are provided between the first bearing bosses 3, and a plurality of third bearing bosses 5 are also provided on the upper end face 1, the bearing areas of the first bearing boss 3, the second bearing boss 4 and the third bearing boss 5 become smaller in sequence, and the heights of the first bearing boss 3, the second bearing boss 4 and the third bearing boss 5 increase in sequence.

[0032] In this embodiment, the cross section of the first bearing boss 3 is elliptical, and the longitudinal sections relative to the long axis of the first bearing boss 3 are parallel to each other.

[0033] In this embodiment, the cross section of the second bearing boss 4 is elliptical, the long axis longitudinal sections of the four second bearing bosses 4 are parallel to each other, and the long axis longitudinal sections of the second bearing boss 4 are perpendicular to the travel direction of the rail.

[0034] In this embodiment, the cross section of the third bearing boss 5 is circular.

[0035] In this embodiment, a plurality of concave circular holes 6 are disposed on the lower end surface 2 , and the concave circular holes 6 are of different sizes.

[0036] In this embodiment, a row of concave circular holes 6 are provided on the intersection line of the long axis longitudinal section and the lower end surface 2 of the first bearing boss 3 and the second bearing boss 4. The concave circular hole 6 corresponding to the center bottom of the first bearing boss 3 is the largest, and the concave circular holes 6 on both sides of the largest concave circular hole 6 gradually become smaller; the concave circular hole 6 corresponding to the center bottom of the second bearing boss 4 is the largest, and the concave circular holes 6 on both sides of the largest concave circular hole 6 gradually become smaller.

[0037] In this embodiment, the first bearing boss 3 occupies 35-43% of the area of ​​the upper end surface (any of the above ranges, such as 40%), the second bearing boss 4 occupies 25-30% of the area of ​​the upper end surface (any of the above ranges, such as 30%), and the third bearing boss 5 occupies 15-20% of the area of ​​the upper end surface (any of the above ranges, such as 20%).

[0038] In this embodiment, the height difference between the first bearing boss 3 and the second bearing boss 4 is 0.2-2 mm (any of the above ranges), and the height difference between the second bearing boss 4 and the third bearing boss 5 is 0.2-2 mm (any of the above ranges).

[0039] In this embodiment, the elastic pad is structurally designed. By optimizing the upper end surface 1 and combining the first bearing boss 3, the second bearing boss 4 and the third bearing boss 5 of different heights and different bearing areas, free conversion between high stiffness and low stiffness can be achieved to meet special working conditions such as no-load, half-load, full-load, heavy load and off-center load.

[0040] Embodiment 2:

[0041] like Figure 5 FIG. 2 is another schematic diagram of the structure of the elastic pad in this embodiment. Compared with the elastic pad in embodiment 1, the elastic pad in this embodiment is different in shape from the first bearing boss 3 and the second bearing boss 4. In this embodiment, the cross-section of the first bearing boss 3 and the second bearing boss 4 is a rounded rectangle.

[0042] The number and shape of the first bearing boss 3 , the second bearing boss 4 and the third bearing boss 5 in the above embodiment are only for reference and are not limited to the number and shape specified above.

Claims

1. An elastic pad, comprising an upper end surface (1) in contact with a rail and a lower end surface (2) in contact with a sleeper, characterized in that: The upper end surface (1) is provided with first bearing bosses (3) on all sides, a plurality of second bearing bosses (4) are provided between the first bearing bosses (3), and a plurality of third bearing bosses (5) are also provided on the upper end surface (1), the bearing areas of the first bearing bosses (3), the second bearing bosses (4) and the third bearing bosses (5) decrease in sequence, and the heights of the first bearing bosses (3), the second bearing bosses (4) and the third bearing bosses (5) increase in sequence; The cross section of the first bearing boss (3) is an ellipse or a rounded rectangle, and the longitudinal sections relative to the long axis of the first bearing boss (3) are parallel to each other; The cross section of the second bearing boss (4) is an ellipse or a rounded rectangle, the long axis longitudinal sections of a plurality of the second bearing bosses (4) are parallel to each other, and the long axis longitudinal sections of the second bearing bosses (4) are perpendicular to the travel direction of the rail; The cross section of the third bearing boss (5) is circular, elliptical or square with rounded corners; The lower end surface (2) is provided with a plurality of concave circular holes (6), and the concave circular holes (6) are of different sizes; A row of concave circular holes (6) are provided on the intersection line between the long axis longitudinal section and the lower end surface (2) of the first bearing boss (3) and the second bearing boss (4); The concave circular hole (6) corresponding to the center bottom of the first bearing boss (3) is the largest, and the concave circular holes (6) on both sides of the largest concave circular hole (6) gradually become smaller; the concave circular hole (6) corresponding to the center bottom of the second bearing boss (4) is the largest, and the concave circular holes (6) on both sides of the largest concave circular hole (6) gradually become smaller.

2. The elastic pad according to claim 1, characterized in that: The first bearing boss (3) occupies 35-43% of the area of ​​the upper end surface (1), the second bearing boss (4) occupies 25-30% of the area of ​​the upper end surface (1), and the third bearing boss (5) occupies 15-20% of the area of ​​the upper end surface (1).

3. The elastic pad according to claim 1, characterized in that: The height difference between the first bearing boss (3) and the second bearing boss (4) is 0.2-2 mm, and the height difference between the second bearing boss (4) and the third bearing boss (5) is 0.2-2 mm.

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