Synthetic brake shoe

Abstract

The application discloses a synthetic brake shoe and relates to the technical field of brake shoes for trains, to solve the problems of poor heat conduction performance of the synthetic brake shoe and expansion extrusion and shrinkage cracks caused in the braking process. The synthetic brake shoe comprises a steel back and a friction body; the friction body is arranged on one side of the steel back; the friction body comprises an insert and a synthetic friction material part; heat dissipation grooves are formed between the insert and the synthetic friction material part; and the far side of the insert from the steel back and the far side of the synthetic friction material part from the steel back are coplanar to form a friction surface of the friction body. The synthetic brake shoe provided by the application improves the heat conduction performance of the synthetic brake shoe through the synergistic effect of the insert and the heat dissipation grooves, and can effectively avoid the problems of mutual extrusion of the synthetic friction material part and the insert and shrinkage cracks after cooling caused by the difference in thermal properties.

Description

Technical Field

[0001] This utility model relates to the field of brake shoes for trains, and in particular to a synthetic brake shoe. Background Technology

[0002] In the field of railway vehicle braking, brake shoes, as key friction components, are of paramount importance. Currently, widely used brake shoes are mainly divided into three categories: cast iron brake shoes, powder metallurgy brake shoes, and composite brake shoes. Cast iron brake shoes, as the traditional type, are not only very heavy but also have poor wear resistance and short service life, resulting in high maintenance costs. Powder metallurgy brake shoes have advantages such as high friction coefficient, good thermal conductivity, strong stability, low wear, and long service life; however, their manufacturing cost is extremely high, limiting their widespread application. Composite brake shoes are favored due to their lightweight advantage, but these brake shoes have insufficient heat resistance and are prone to thermal fade. More importantly, their poor thermal conductivity causes a large amount of heat generated by braking friction to accumulate on the wheel surface, causing changes in the microstructure of the wheel material, leading to serious damage such as thermal cracking, thermal crazing, and even thermal delamination. The delamination of wheel material can also embed into the composite brake shoe, forming a metal inlay, further deteriorating the braking effect. In addition, composite brake shoes may crack during braking, affecting the structural integrity of the brake shoe. Utility Model Content

[0003] The purpose of this invention is to provide a synthetic brake shoe to improve the thermal conductivity of the synthetic brake shoe and reduce the risk of cracking during braking.

[0004] To achieve the above objectives, this utility model provides the following technical solution: A synthetic brake shoe, comprising: Steel back; A friction body is disposed on one side of the steel back. The friction body includes an insert and a synthetic friction material portion. A heat dissipation groove is formed between the insert and the synthetic friction material portion. The side of the insert away from the steel back and the side of the synthetic friction material portion away from the steel back are coplanar to form the friction surface of the friction body.

[0005] Optionally, the number of inserts is at least one, the number of synthetic friction material portions is at least two, and each insert is located between two adjacent synthetic friction material portions.

[0006] Optionally, the inserts and the synthetic friction material portions are arranged alternately at intervals along the length and / or width direction of the steel back.

[0007] Optionally, the friction coefficients of the insert and the synthetic friction material are of the same friction level.

[0008] Optionally, the synthetic friction material is cold-pressed onto one side of the steel backing.

[0009] Optionally, the insert is welded and fixed to the steel backing.

[0010] Optionally, the width of the heat dissipation groove is 5mm-15mm.

[0011] Optionally, the friction area of ​​the insert is 10%-20% of the friction surface area.

[0012] Optionally, the insert is made of cast iron or powder metallurgy material.

[0013] Optionally, the cast iron is ductile iron, gray cast iron, or high-phosphorus cast iron.

[0014] Compared with the prior art, the beneficial effects of this utility model's technical solution are as follows: This invention provides a synthetic brake shoe that significantly enhances the heat dissipation capacity of the friction surface by spaced-apart inserts and synthetic friction material to form heat dissipation grooves. The inserts, with their excellent thermal conductivity, rapidly dissipate frictional heat, effectively improving the thermal conductivity of the friction body. Simultaneously, the heat dissipation grooves on the friction surface greatly increase the heat dissipation area. The synergistic effect of these two elements creates an efficient heat dissipation path, effectively dissipating the large amount of heat generated during braking. This effectively alleviates the thermal fade phenomenon of the synthetic brake shoe, reduces the concentrated heat transfer to the wheel, and prevents wheel failures such as thermal cracking, thermal crazing, and thermal peeling due to high temperatures. Furthermore, it prevents peeled wheel material from embedding into the synthetic brake shoe, forming metal embeddings. More importantly, the heat dissipation grooves separate the inserts and synthetic friction material, preventing them from contacting each other. This effectively avoids the mutual compression and shrinkage cracking problems caused by the difference in thermophysical properties between the synthetic friction material and the insert material during braking. This extends the service life of the brake shoe itself and improves the operational safety of the braking system. Attached Figure Description

[0015] The accompanying drawings, which are included to provide a further understanding of the present invention and constitute a part of this invention, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a schematic diagram of a synthetic brake shoe provided for an embodiment of the present invention.

[0016] Reference numerals: 1-Steel back; 2-Friction body; 201-Insert; 202-Synthetic friction material part; 203-Heat dissipation groove; 3-Hook. Detailed Implementation

[0017] To make the technical problems, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0018] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0019] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified. "Several" means one or more, unless otherwise explicitly specified.

[0020] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" 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; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0021] Please see Figure 1This utility model provides a synthetic brake shoe, comprising: a steel backing 1 and a friction body 2; wherein, the friction body 2 is disposed on one side of the steel backing 1, which is the side closest to the wheel tread when the train brakes. The friction body 2 includes an insert 201 and a synthetic friction material portion 202. The insert 201 can improve the thermal conductivity of the synthetic brake shoe and increase the heat dissipation efficiency; the main material of the synthetic friction material portion 202 is a composite material such as resin, rubber, ceramic or graphite, and can be the same material as the synthetic friction material of conventional synthetic brake shoes. The hardness of the insert 201 is greater than the hardness of the synthetic friction material portion 202. A heat dissipation groove 203 is formed between the insert 201 and the synthetic friction material portion 202. The insert 201 and the synthetic friction material portion 202 are not continuously disposed, but are spaced apart from each other, and the space between them is the heat dissipation groove 203. The side of the insert 201 away from the steel back 1 and the side of the synthetic friction material part 202 away from the steel back 1 are coplanar to form the friction surface of the friction body 2. The top of the insert 201 is coplanar with the top of the synthetic friction material part 202, forming a flat and uniform friction surface, which ensures that the wheel tread can smoothly slide over the brake shoe friction surface and ensures braking stability.

[0022] During train braking, the flat friction surface formed by the coplanar arrangement of the insert 201 and the synthetic friction material 202 contacts the wheel. The synthetic friction material 202 provides stable friction, while the insert 201, with its excellent thermal conductivity, quickly dissipates the heat generated by friction. The heat dissipation grooves 203 formed by the spaced insert 201 and the synthetic friction material 202 increase convective heat dissipation, effectively suppressing heat fade. The wheel tread can continuously and smoothly glide across the friction surface composed of the insert 201 and the synthetic friction material 202.

[0023] As can be seen from the above scheme and specific implementation process, the composite brake shoe provided by this utility model effectively alleviates the thermal fade phenomenon and ensures the safety of train braking through the combination of the insert 201 and the heat dissipation groove 203. The steel backing 1 is the structural foundation of the entire composite brake shoe, providing a supporting framework. The insert 201 can improve the thermal conductivity of the composite brake shoe and increase heat dissipation efficiency. The composite friction material part 202 is the main body of the friction function and the main source of braking force. The heat dissipation groove 203 increases the heat dissipation area. The insert 201 and the heat dissipation groove 203 work together to form a highly efficient heat dissipation system, effectively suppressing heat fade, reducing concentrated heat transfer to the wheel, and preventing wheel failures such as thermal cracking, thermal crazing, and thermal peeling due to high temperatures. This also prevents peeled wheel material from embedding into the synthetic brake shoe, forming a metal embedding. Debris generated during braking falls into the heat dissipation groove 203, effectively suppressing metal embedding in the synthetic brake shoe. Furthermore, the heat dissipation groove 203 forms a physical gap between the insert 201 and the synthetic friction material part 202, creating a buffer zone for differences in thermal properties. The heat dissipation groove 203 effectively avoids thermal stress concentration caused by the difference in thermal expansion coefficients between the insert 201 and the synthetic friction material part 202, significantly reducing the risk of interface cracking and shrinkage cracking. The insert 201 and the synthetic friction material part 202 are coplanar, jointly forming a stable and uniform friction surface.

[0024] like Figure 1 As shown, in some embodiments, the number of inserts 201 is at least one, specifically one, two, three, or more; the number of synthetic friction material portions 202 is at least two, specifically two, three, four, or more. Each insert 201 is located between two adjacent synthetic friction material portions 202. By placing the inserts 201 between two adjacent synthetic friction material portions 202, the highly thermally conductive inserts 201 are evenly distributed in the friction body 2, effectively improving the thermal conductivity of the friction body 2 and significantly enhancing its thermal stability, thereby effectively suppressing thermal fade during braking.

[0025] like Figure 1 As shown, in some embodiments, the insert 201 and the composite friction material portion 202 are arranged alternately along the length and / or width direction of the steel back 1. This arrangement forms a heat dissipation channel penetrating the friction body 2, which not only ensures that the highly thermally conductive insert 201 is evenly distributed within the friction body, achieving rapid heat diffusion, but also ensures the uniform distribution of braking pressure on the overall friction surface. This ensures that the composite friction material portion 202 and the insert 201 can achieve functional synergy in any region, guaranteeing the thermal stability of the composite brake shoe during braking.

[0026] For example, the number of inserts 201 can be one, and the number of synthetic friction material parts 202 can be two. The inserts 201 are located between the two synthetic friction material parts 202, and the inserts 201 and synthetic friction parts 202 are arranged alternately along the length direction of the steel back 1.

[0027] like Figure 1 As shown, in some embodiments, the friction coefficients of the insert 201 and the composite friction material 202 belong to the same friction grade. Specifically, a friction coefficient below 0.1 is classified as low friction grade, a friction coefficient between 0.1 and 0.3 as medium friction grade, and a friction coefficient above 0.3 as high friction grade. Having the insert 201 and the composite friction material 202 belong to the same friction grade ensures consistent frictional performance during braking.

[0028] like Figure 1 As shown, in some embodiments, the synthetic friction material portion 202 is cold-pressed onto one side of the steel backing 1. Cold pressing allows the synthetic friction material portion 202 to bond more evenly with the steel backing 1, effectively resisting the vibration and impact generated by friction during braking, reducing the risk of the synthetic friction material portion 202 falling off, and ensuring the stable performance of the synthetic brake shoe during braking.

[0029] like Figure 1 As shown, in some embodiments, the insert 201 is welded and fixed to the steel backing 1. Welding and fixing can make the connection between the steel backing 1 and the insert 201 more secure, which can effectively prevent the insert 201 from loosening, shifting, or even falling off. It can also make the frictional heat conducted by the insert 201 more quickly transferred to the steel backing 1, greatly improving the heat dissipation efficiency of the composite brake shoe, and effectively avoiding the risk of the insert 201 loosening.

[0030] like Figure 1 As shown, in some embodiments, the width of the heat dissipation groove 203 is 5mm-15mm, specifically 5mm, 7.5mm, 10mm, 12.5mm, or 15mm. If the width of the heat dissipation groove 203 is less than 5mm, it will restrict airflow and debris discharge, reducing heat dissipation efficiency; if the width of the heat dissipation groove 203 is greater than 15mm, it may reduce the effective contact area between the friction surface and the wheel tread, reducing braking force and affecting braking performance. Therefore, considering both heat dissipation efficiency and braking performance, the width of the heat dissipation groove 203 is selected to be 5mm-15mm.

[0031] like Figure 1As shown, in some embodiments, the friction area of ​​the insert 201 is 10%-20% of the friction surface area, specifically 10%, 12%, 15%, 17%, or 20%. If the friction area of ​​the insert 201 is less than 10% of the friction surface area, the effective heat conduction path formed by the insert 201 is too small, reducing heat dissipation efficiency. Furthermore, due to the poor heat resistance of the synthetic brake shoe, thermal decay occurs, and the heat generated by friction concentrates on the wheel, causing changes in the wheel's structure. In severe cases, thermal cracks, thermal crazing, and thermal peeling may occur. The peeled material will embed into the synthetic brake shoe, forming a metal inlay. The insert 201 can repair the peeled material on the wheel tread through friction and grinding. If the friction area of ​​the insert 201 is too small, it will affect the wheel repair effect. If the friction area of ​​the insert 201 is greater than 20% of the friction surface area, the excessively large insert 201 will directly aggravate wear, not only shortening its own lifespan but also increasing the abnormal wear of the synthetic brake shoe, thereby increasing maintenance costs. Therefore, considering the heat dissipation effect, wheel repair effect and wear and tear of the insert 201, the friction area of ​​the insert 201 can be 10%-20% of the friction surface area.

[0032] like Figure 1 As shown, in some embodiments, the steel backing 1 is provided with a brake shoe hook 3. The brake shoe hook 3 enables the rapid installation of the composite brake shoe and effectively limits the offset of the composite brake shoe, improving the efficiency of disassembly and assembly while ensuring the stability of the structural connection, and providing important structural protection for train safety.

[0033] like Figure 1 As shown, in some embodiments, the insert 201 is made of cast iron or powder metallurgy material. Both materials possess high wear resistance, excellent thermal conductivity, and good high-temperature stability, enabling them to effectively conduct frictional heat and resist wear under continuous braking conditions. This improves the heat dissipation efficiency of the composite brake shoe while extending its service life. The hardness of these materials is greater than that of the composite friction material part 202. For example, the cast iron can be ductile iron, gray cast iron, or high-phosphorus cast iron, which can meet the differentiated requirements for the mechanical and frictional properties of the insert 201 under different braking conditions.

[0034] It should be noted that the terms "embodiment," "example," "specific example," etc., used in this specification refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0035] It is understood that the above-described specific embodiments have provided a detailed explanation of the purpose, technical solution and beneficial effects of this utility model. It should be understood that the above description is only a specific embodiment of this utility model and is not intended to limit this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A synthetic brake shoe, characterized in that, include: Steel back (1); Friction body (2) is disposed on one side of the steel back (1). The friction body (2) includes an insert (201) and a synthetic friction material part (202). A heat dissipation groove (203) is formed between the insert (201) and the synthetic friction material part (202). The side of the insert (201) away from the steel back (1) and the side of the synthetic friction material part (202) away from the steel back (1) are coplanar to form the friction surface of the friction body (2).

2. The composite brake shoe according to claim 1, characterized in that, The number of the inserts (201) is at least one, and the number of the synthetic friction material parts (202) is at least two, with each insert (201) located between two adjacent synthetic friction material parts (202).

3. The composite brake shoe according to claim 1, characterized in that, The insert (201) and the synthetic friction material part (202) are arranged alternately along the length and / or width of the steel back (1).

4. The composite brake shoe according to claim 1, characterized in that, The friction coefficients of the insert (201) and the synthetic friction material (202) belong to the same friction level.

5. The composite brake shoe according to claim 1, characterized in that, The synthetic friction material part (202) is cold-pressed onto one side of the steel back (1).

6. The composite brake shoe according to claim 1, characterized in that, The insert (201) is welded and fixed to the steel back (1).

7. The composite brake shoe according to claim 1, characterized in that, The width of the heat dissipation groove (203) is 5mm-15mm.

8. The composite brake shoe according to claim 1, characterized in that, The friction area of ​​the insert (201) is 10%-20% of the friction surface area.

9. The composite brake shoe according to claim 1, characterized in that, The insert (201) is made of cast iron or powder metallurgy material.

10. The composite brake shoe according to claim 9, characterized in that, The cast iron is ductile iron, gray cast iron, or high-phosphorus cast iron.

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