All-carbon ceramic wheel-mounted brake disc and vehicle using same

Abstract

The invention provides an all-carbon ceramic wheel-mounted brake disc and a vehicle using the same, and relates to the technical field of railway vehicle braking, and the all-carbon ceramic wheel-mounted brake disc comprises at least two all-carbon ceramic brake disc bodies and fasteners; the all-carbon ceramic brake disc body is fixed to the two sides of a wheel through the fasteners to clamp the wheel. The all-carbon ceramic brake disc body comprises a friction ring and a plurality of radiating ribs; the heat dissipation ribs are arranged on the supporting face of the friction ring, each heat dissipation rib is provided with at least two circumferential air mixing channels, and radial air mixing channels are arranged between the heat dissipation ribs. According to the all-carbon ceramic wheel-mounted brake disc and the vehicle using the all-carbon ceramic wheel-mounted brake disc, the characteristics of light weight, high heat capacity, low wind resistance and the like are achieved, reliable fastening connection is ensured, maintenance is facilitated, replacement and verification on an existing vehicle are facilitated, and the overall performance and safety are improved.

Description

Technical Field

[0001] The present application relates to the technical field of rail vehicle braking, and in particular to a full carbon ceramic wheel mounted brake disc and a vehicle using the same. Background Art

[0002] The brake disc is a key component of the basic brake system of high-speed EMUs. During the braking process of the train, the friction between the brake disc and the brake pad generates a braking torque to achieve the effect of slowing down and stopping the train. At the same time, during the braking process, the kinetic energy of the train is converted into heat energy, which is mainly absorbed by the brake disc and finally dissipated into the air through the convection heat exchange between the brake disc and the air. According to the different installation locations, the brake disc can be divided into two types: wheel-mounted brake disc and axle-mounted brake disc.

[0003] The 400 km / h high-speed EMU requires that the basic braking device ensures the braking safety of 400 km / h while also putting forward new requirements for the lightweight of the train.

[0004] Due to the difference in braking energy, different brake disc materials are suitable for different speed levels. The 350km / h EMU uses alloy steel brake discs, which have the advantages of high strength, easy processing and high temperature resistance, and have been widely used. However, the disadvantages of this material are high density, heavy weight, and increased unsprung weight of the train. Carbon ceramic material has the advantages of low density, light weight and high temperature resistance. While meeting the braking performance requirements, it greatly reduces the unsprung weight, improves the energy consumption and dynamic performance of the train, and is one of the most promising brake disc materials for high-speed EMUs with a speed of 400 kilometers per hour.

[0005] In order to enhance the convective heat exchange between the brake disc and the air, the brake disc of high-speed trains usually adopts a ventilation structure design. The wheel-mounted brake disc consists of two parts: a friction ring and a heat dissipation rib. The friction ring mainly plays the role of friction and heat storage, while the heat dissipation rib can increase air convection and improve the heat dissipation capacity of the brake disc. The total thickness of the brake disc, the thickness of the friction ring and the thickness of the heat dissipation rib constitute the basic dimension chain of the brake disc. When the total thickness of the brake disc remains unchanged as the interface dimension, the thickness of the heat dissipation rib is increased, and the thickness of the friction ring is reduced. The effect is that the ventilation and heat dissipation capacity of the brake disc is increased, and the heat storage capacity of the brake disc is reduced; conversely, the heat storage capacity of the brake disc is increased, and the ventilation and heat dissipation capacity is reduced. The existing 350km / h EMU steel wheel-mounted brake disc body thickness dimension chain is as follows Figure 1 As shown, the thickness of the friction ring is between 18-22 mm, and the thickness of the heat dissipation rib is between 24.5-28.5.

[0006] In addition, the cooling ribs of the brake disc with ventilation structure have a pumping effect. The drive of the brake disc needs to be powered by the vehicle's drive device, which is a loss of traction power. The ventilated brake disc not only converts energy during braking, but also consumes some power when not braking due to the pumping effect of the brake disc, resulting in energy waste. The pumping power is mainly related to the thickness and shape distribution of the brake disc cooling ribs.

[0007] From the above content, it can be seen that the application of carbon ceramic materials in wheel-mounted brake discs of high-speed EMUs with a speed of 400 kilometers per hour has the following technical difficulties:

[0008] 1. Although carbon ceramic materials are resistant to high temperatures, their volume specific heat capacity is lower than that of steel materials. If the heat dissipation rib / friction ring thickness ratio of steel brake discs is used, the heat capacity will be insufficient, resulting in excessively high extreme temperatures during braking, causing a series of problems such as thermal decay of the brake pads. At the same time, a larger heat dissipation rib thickness brings a greater pumping power, resulting in a loss of traction power.

[0009] 2. The geometric shape of the heat dissipation ribs has a great influence on the heat dissipation capacity. At the same time, due to the difficult processing and poor mechanical properties of carbon-ceramic materials, the heat dissipation rib form of the original steel disc is no longer suitable for carbon-ceramic composite brake discs.

[0010] 3. Carbon ceramic material is an anisotropic material with a layered structure. The SiC microscopic distribution is uneven, and the carbon fiber material is easily oxidized and corroded. When it is directly used as a friction interface to match the brake pad, the friction coefficient fluctuates greatly and the brake pad wear is large.

[0011] 4. In the existing fastener solution for steel brake discs, the fasteners and clamped parts are made of steel, and the thermal expansion coefficients are similar. During the braking temperature rise process, the thermal expansion and deformation are coordinated with each other, and there will be no problem of axial force attenuation. However, the thermal expansion coefficient of carbon ceramic materials is very low, about 1 / 2 of that of steel materials. The existing steel brake disc fastener solution causes the problem of bolt axial force attenuation during braking.

[0012] 5. The braking energy of high-speed trains is huge. The braking energy absorbed by the brake disc is transmitted to the locating pin, causing the locating pin to expand and deform due to heat, and it is easy to expand and tighten in the locating pin installation hole. Summary of the invention

[0013] In response to the problems in the prior art, the embodiments of the present application provide a full carbon-ceramic wheel-mounted brake disc and a vehicle using the same, which can solve the technical difficulties in applying carbon-ceramic materials to high-speed EMU wheel-mounted brake discs and meet the requirements of high-speed EMUs for brake safety, maintenance friendliness, energy saving and lightweight of brake discs.

[0014] In a first aspect, the present application provides a full carbon ceramic wheel mounted brake disc, comprising: at least two full carbon ceramic brake disc bodies;

[0015] The full carbon ceramic brake disc body is fixed to both sides of the wheel by the fasteners to clamp the wheel;

[0016] The full carbon ceramic brake disc body includes a friction ring and a plurality of heat dissipation ribs; the heat dissipation ribs are arranged on the supporting surface of the friction ring, each of the heat dissipation ribs is provided with at least two circumferential air flow channels, and radial air flow channels are provided between each of the heat dissipation ribs.

[0017] Furthermore, the full carbon ceramic brake disc body comprises: a first brake disc body and a second brake disc body; the first brake disc body and the second brake disc body are fixed to both sides of the wheel by a fastener; the fastener comprises a bolt, a bolt sleeve, a gasket and a nut;

[0018] The bolt passes through the bolt sleeve, the first brake disc body, the wheel, the second brake disc body and the gasket in sequence, and is fastened to the nut.

[0019] Furthermore, the material of the bolt is martensitic stainless steel or alloy steel with a low thermal expansion coefficient; the material of the bolt sleeve and the gasket is austenitic steel with a high thermal expansion coefficient.

[0020] Furthermore, the thickness of the friction ring is 31 mm to 37 mm, and the thickness of the heat dissipation rib is 15.5 mm to 9.5 mm.

[0021] Furthermore, the thickness of the friction ring and the thickness of the heat dissipation rib are calculated by a single-variable multi-objective optimization model.

[0022] Furthermore, a wear-resistant ceramic coating is prepared on the friction surface of the friction ring.

[0023] Furthermore, the wear-resistant ceramic coating is prepared by adopting a retreat design.

[0024] Further, it also includes: a positioning pin;

[0025] The full carbon ceramic brake disc body is provided with a positioning groove, and the positioning pin passes through the mounting hole of the wheel and is inserted into the positioning groove to fix the full carbon ceramic brake disc body on both sides of the wheel.

[0026] Furthermore, the body of the positioning pin includes two positioning parts; a through hole is provided at the central axis of the positioning part, and a slit-shaped opening communicating with the through hole is provided on the side of the body.

[0027] Furthermore, the heat dissipation rib has a mallet shape when viewed from above.

[0028] In a second aspect, the present application provides a vehicle having a full-carbon ceramic wheel-mounted brake disc as described in any of the above embodiments, wherein the full-carbon ceramic wheel-mounted brake disc is arranged on a wheel to brake the wheel.

[0029] The full-carbon ceramic wheel-mounted brake disc and the vehicle using the same provided by the present application are provided with at least two full-carbon ceramic brake disc bodies and fasteners; the full-carbon ceramic brake disc bodies are fixed to both sides of the wheel by the fasteners to clamp the wheel; the full-carbon ceramic brake disc body includes a friction ring and a plurality of heat dissipation ribs; the heat dissipation ribs are arranged on the supporting surface of the friction ring, each of the heat dissipation ribs is provided with at least two circumferential air-flowing channels, and radial air-flowing channels are provided between each of the heat dissipation ribs, thereby achieving the characteristics of lightweight, high heat capacity and low wind resistance, ensuring a reliable fastening connection, facilitating maintenance and facilitating replacement and verification on existing vehicles, and improving overall performance and safety.

[0030] Among them, the wheel-mounted brake disc body is made of all-carbon-ceramic composite material, which reduces weight by more than 50% compared with traditional steel brake discs, and reduces weight by more than 20% compared with carbon-ceramic brake discs with steel support structures; the wheel-mounted brake disc body is designed based on a multi-objective optimization of aerodynamics and multi-physics field coupling simulation, including "hammer-shaped" heat dissipation ribs and unique friction ring / heat dissipation rib thickness, so that the wheel-mounted brake disc body has the characteristics of high heat capacity and low pumping power, effectively reducing continuous braking temperature rise and energy loss caused by pumping power; the friction surface of the wheel-mounted brake disc body adopts a wear-resistant ceramic coating design with identifiable thickness, and the wear-resistant functional coating thickness is used as the wear limit structure, which can ensure the wear and tear condition of the brake disc. It can be easily identified with the naked eye, and while maintaining the same maintenance habits as existing brake discs, the friction and wear of the brake discs can be guaranteed to remain stable during their service life; the fasteners have thermal deformation coordination capabilities, which can effectively prevent the attenuation of the fastening connection preload caused by the low thermal expansion coefficient of the carbon ceramic material due to high braking temperature, thereby ensuring the reliability of the fastening connection; the locating pin adopts an elastic opening structure, which can prevent the locating pin from expanding and deforming in the wheel mounting hole due to braking heat, which is conducive to disassembly and replacement during maintenance; the full carbon ceramic wheel-mounted brake disc has the same interface size as the existing high-speed EMU wheel-mounted brake disc, which can realize the replacement of existing steel brake discs, and facilitate the use of existing vehicle resources to replace and verify the full carbon ceramic wheel-mounted brake disc. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present application 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 only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 This is a schematic diagram of the thickness dimension chain of the existing 350km / h EMU steel wheel-mounted brake disc body;

[0033] Figure 2This is a schematic diagram of the structure of a full carbon-ceramic wheel-shaped brake disc provided in one embodiment of the present application;

[0034] Figure 3 It is a schematic diagram of airflow flowing through a radial air flow channel and a circumferential air flow channel provided by an embodiment of the present application;

[0035] Figure 4 This is a schematic diagram of the structural relationship between a full carbon-ceramic wheel-shaped brake disc, a fastener, and a wheel provided in one embodiment of the present application;

[0036] Figure 5 is a schematic diagram of the structure and materials of a fastener provided in one embodiment of the present application;

[0037] Figure 6 is a schematic diagram of the structure and materials of a fastener provided in one embodiment of the present application;

[0038] Figure 7 is a schematic diagram of the structure and materials of a fastener provided in one embodiment of the present application;

[0039] Figure 8 is a schematic cross-sectional view of the thickness of the friction ring and the heat dissipation ribs provided in one embodiment of the present application;

[0040] Fig. 9 It is a comparison chart of the temperature rise curves of the full carbon-ceramic wheel-mounted brake disc provided in one embodiment of the present application and the existing wheel-mounted brake disc during two consecutive emergency braking processes at 400 km / h;

[0041] Fig.10 2 is a schematic structural diagram of a wear-resistant ceramic coating of a full-carbon ceramic wheel-shaped brake disc provided in an embodiment of the present application;

[0042] Fig.11 It is an exploded view of the assembly relationship of a full carbon-ceramic wheel-shaped brake disc provided in one embodiment of the present application;

[0043] Fig.12 It is an assembly relationship diagram of a positioning pin, a first brake disc body, a second brake disc body and a wheel provided in an embodiment of the present application;

[0044] Fig.13 It is a schematic diagram of the structure of a positioning pin provided in one embodiment of the present application. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the embodiments of the present application are further described in detail below in conjunction with the accompanying drawings. Here, the illustrative embodiments of the present application and their descriptions are used to explain the present application, but are not intended to limit the present application. It should be noted that, in the absence of conflict, the embodiments in the present application and the features in the embodiments can be combined arbitrarily with each other.

[0046] Figure 2 is a schematic diagram of the structure of a full carbon-ceramic wheel-shaped brake disc provided in an embodiment of the present application, such as Figure 2 As shown, the full carbon ceramic wheel-shaped brake disc provided by the present application comprises: at least two full carbon ceramic brake disc bodies 1;

[0047] The full carbon ceramic brake disc body 1 is fixed on both sides of the wheel to clamp the wheel;

[0048] The full carbon ceramic brake disc body 1 includes a friction ring 12 and a plurality of heat dissipation ribs 11 ; the heat dissipation ribs 11 are arranged on the supporting surface of the friction ring 12 , each of the heat dissipation ribs 11 is provided with at least two circumferential air flow channels 16 , and radial air flow channels 13 are provided between each of the heat dissipation ribs 11 .

[0049] Specifically, the all-carbon-ceramic wheel-shaped brake disc provided in the present application can solve the technical problems of insufficient thermal capacity, large pump air loss, unstable friction and wear performance, difficult identification of wear life, high-temperature relaxation and failure of fasteners, and thermal expansion and jamming of locating pins that make disassembly and assembly difficult when carbon-ceramic brake discs are used in high-speed EMUs with a speed of 400 kilometers per hour.

[0050] The mechanical properties of carbon-ceramic composite materials are lower than those of steel materials, and the molding process is difficult. The slender strip-shaped heat dissipation ribs 11 used in the original steel brake disc are not suitable for carbon-ceramic composite brake discs. The heat dissipation ribs 11 of the full carbon-ceramic wheel-mounted brake disc body are designed based on the mechanical properties of the carbon-ceramic composite material and the aerodynamic principle. The upper and lower surfaces of the substrate of the friction ring 12 are the friction surface and the support surface respectively. A plurality of heat dissipation ribs 11 are evenly distributed along the circumference on the support surface of the friction ring 12. The use of evenly distributed heat dissipation ribs 11 is conducive to the uniform distribution of the temperature field and reduces the thermal stress caused by the temperature gradient. A radial series air duct is left between two adjacent heat dissipation ribs 11, which can achieve the effect of enhancing convective heat transfer. At the same time, at least two annular circumferential series air ducts are arranged on the heat dissipation ribs 11 along the circumferential direction. The circumferential series air duct can effectively reduce the pumping resistance of the brake disc, while ensuring the convective heat transfer capacity of the brake disc, reducing the consumption of traction power caused by the pumping resistance of the brake disc. The shape and arrangement of the heat dissipation ribs 11 provided in the present application are significantly different from the shape and non-uniform arrangement of the slat ribs of the existing steel brake disc.

[0051] In one embodiment, if Figure 2 As shown, the heat dissipation rib 11 is in the shape of a mallet when viewed from above.

[0052] Specifically, the basic shape of the heat dissipation ribs 11 is a mallet shape with a large end and a narrow end. A plurality of heat dissipation ribs 11 with the same outer profile are evenly distributed on the friction ring 12, so that a radial air flow channel 13 with a wide inlet and a narrow outlet is left between the heat dissipation ribs 11. Figure 2As shown, the air duct inlet 15 is relatively wide and then gradually narrows, the airflow is accelerated in the channel and flows out from the air outlet 14, thus enhancing the convective heat transfer effect of the full carbon ceramic wheel mounted brake disc. Figure 3 The figure shows a schematic diagram of airflow passing through the radial air flow channel 13 and the circumferential air flow channel 16 .

[0053] In one embodiment, if Figure 2 As shown, the number of the heat dissipation ribs 11 is 24, but the present application is not limited thereto.

[0054] Figure 4 FIG. 1 is a schematic diagram of the structural relationship between a full carbon-ceramic wheel-shaped brake disc, a fastener, and a wheel provided in an embodiment of the present application. Figure 4 As shown, the full carbon ceramic brake disc body 1 includes: a first brake disc body 101 and a second brake disc body 102; the first brake disc body 101 and the second brake disc body 102 are fixed to both sides of the wheel 100 by a fastener 2; the fastener 2 includes a bolt 21, a bolt sleeve 22, a gasket 23 and a nut 24;

[0055] The bolt 21 passes through the bolt sleeve 22 , the first brake disc body 101 , the wheel 100 , the second brake disc body 102 , and the washer 23 in sequence, and is fastened to the nut 24 .

[0056] Specifically, the wheel-mounted brake disc is clamped on both sides of the spoke plate of the wheel 100 by the fasteners 2 during installation. In order to solve the problem of failure of the fastening connection due to relaxation of the pre-tightening force caused by high-temperature thermal expansion because the thermal expansion coefficient of carbon ceramic material is lower than that of steel in the carbon-ceramic wheel-mounted brake disc of the high-speed EMU, the fasteners 2 adopt a high-temperature self-tensioning design.

[0057] The first brake disc body 101 and the second brake disc body 102 are provided with mounting holes for connection with the fastener 2. The bolt 21 passes through the mounting holes of the first brake disc body 101 and the second brake disc body 102 to fix them to the wheel 100. The head of the bolt 21 is located on the outside of the first brake disc body 101. The bolt sleeve 22 is used to strengthen the connection between the bolt 21 and the first brake disc body 101 and the second brake disc body 102, to ensure that the bolt 21 is not damaged during installation, and to provide additional support. The gasket 23 is located between the nut 24 and the second brake disc body 102, and plays a role in evenly distributing pressure and reducing friction. The nut 24 cooperates with the bolt 21, and after tightening, it ensures that the bolt 21 is stable, and the first brake disc body 101 and the second brake disc body 102 are kept in a fastened state with the wheel 100.

[0058] In one embodiment, the material of the bolt 21 is martensitic stainless steel or alloy steel with a low thermal expansion coefficient; the material of the bolt sleeve 22 and the gasket 23 is austenitic steel with a high thermal expansion coefficient.

[0059] Specifically, the high temperature generated during the braking process of the carbon ceramic brake disc will cause thermal expansion of the parts connected by the bolt 21. Since the thermal expansion coefficient of the carbon ceramic material is relatively small, more than twice that of the steel material, if the existing steel brake disc fastener solution is used, the expansion of the parts connected by the bolt 21 during the braking process will be different, which will cause the pre-tightening force of the bolt 21 to be seriously attenuated. Based on the theory of thermal expansion and deformation coordination, the clamping structure and material of the fastener 2 are as follows: Figure 5 As shown, the fastener 2 has a self-tensioning function at high temperatures, effectively solving the attenuation of the preload force caused by thermal expansion mismatch when the fastening connection is at high temperatures, thereby ensuring the reliability of the fastening connection. An austenitic steel bolt sleeve 22 and a gasket 23 with a high thermal expansion coefficient are added between the bolt 21 and the clamped part to play a tensioning role during the braking temperature rise process. The material of the bolt 21 is selected from martensitic stainless steel or alloy steel with a lower thermal expansion coefficient to reduce the relaxation of the fastener 2 during the braking temperature rise process.

[0060] In one embodiment, the specific material of the fastener 2 is as follows: Figure 6 As shown, the bolt is X19CrMoNbVN11 or other high-temperature resistant alloy steel with a low thermal expansion coefficient, the bolt sleeve and gasket are GH2132 or other austenitic stainless steel, and the nut is 21CrMoV5-7, but the present application is not limited thereto.

[0061] In another embodiment, the specific material of the fastener 2 is as follows: Figure 7 As shown, the bolt is 40CrMoV4-6 or other high-temperature resistant alloy steel with a low thermal expansion coefficient, the bolt sleeve and gasket are GH2132 or other austenitic stainless steel, and the nut is 21CrMoV5-7, but the present application is not limited thereto.

[0062] Figure 8 is a schematic cross-sectional view of the thickness of the friction ring 12 and the heat dissipation rib 11 provided in one embodiment of the present application, such as Figure 8 As shown, the thickness of the friction ring is 31 mm to 37 mm, and the thickness of the heat dissipation rib is 15.5 mm to 9.5 mm.

[0063] Specifically, the total thickness of the existing steel wheel-mounted brake disc for high-speed trains with a speed rating of 350km / h and above is fixed at 46.5mm, of which the friction ring 12 of the brake disc has a thickness of 18mm to 22mm, and the corresponding heat dissipation rib 11 has a thickness of 28.5mm to 24.5mm. The volumetric specific heat capacity of carbon ceramic materials is relatively low compared to steel. If the friction ring 12 thickness / heat dissipation rib 11 thickness ratio design of the steel brake disc is adopted, it will lead to a series of problems such as insufficient heat capacity of the brake disc, excessive temperature rise during continuous emergency braking, and brake thermal decay. Therefore, it is necessary to redesign the thickness of the friction ring 12 / heat dissipation rib 11 of the carbon ceramic brake disc while keeping the brake disc interface size, i.e., the total thickness of 46.5mm unchanged.

[0064] After redesign, the thickness of the friction ring 12 of the full carbon ceramic wheel brake disc for high-speed trains was determined to be 31mm-37mm, and the thickness of the heat dissipation rib was determined to be 15.5mm-9.5mm. The thickness of the friction ring 12 / heat dissipation rib 11 of the full carbon ceramic wheel brake disc is 31mm-37mm / 15.5mm-9.5mm. Under this thickness, the heat capacity and heat dissipation capacity of the brake disc are balanced, and the wind resistance is small, which can meet the heat capacity requirements of two consecutive emergency brakes at 400km / h for EMUs, such as Fig. 9 The figure shows the temperature rise curve comparison between the full carbon ceramic wheel-mounted brake disc provided by the present application and the existing wheel-mounted brake disc during two consecutive emergency braking processes at 400 km / h. The thickness range of the existing steel brake disc ring is obviously different from 18mm to 22mm. The new structural carbon ceramic disc body has a higher heat capacity while still reducing weight by more than 50% compared with the same specification steel brake disc.

[0065] In one embodiment, the preferred thickness of the friction ring 12 of the full carbon ceramic wheel mounted brake disc is 34 mm, the preferred thickness of the heat dissipation rib is 34 mm, and the preferred thickness of the friction ring 12 / heat dissipation rib 11 is 34 mm / 12.5 mm.

[0066] In one embodiment, the thickness of the friction ring and the thickness of the heat dissipation rib are calculated by a single-variable multi-objective optimization model.

[0067] Specifically, since the thickness of the friction ring 12 / heat dissipation rib 11 affects the performance of the brake disc such as heat capacity, heat dissipation capacity, air pumping power, and weight, the thickness of the friction ring 12 is taken as a single variable, and the optimization value range is 22 mm (existing technical solution) to 46.5 mm (solid disc). The optimization objectives are to maximize heat capacity, maximize heat dissipation capacity, minimize air pumping power, and minimize weight. The thickness of the friction ring 12 and the thickness of the heat dissipation rib 11 are calculated using the single variable multi-objective optimization model shown below:

[0068]

[0069] In the formula, E i is the evaluation score, b i Take the value of the variable, y j (b i ) is the objective function value, w j % is the objective function value weight, i=1~n, j=1~k.

[0070] Fig.10 is a schematic diagram of the structure of the wear-resistant ceramic coating of the full carbon ceramic wheel-shaped brake disc provided by an embodiment of the present application, such as Fig.10 As shown, a wear-resistant ceramic coating is prepared on the friction surface of the friction ring 12 .

[0071] Specifically, carbon-ceramic composite materials are anisotropic materials, and the wear properties such as friction coefficient and wear rate are different from the surface to different depths, which causes the instability of vehicle braking performance and hinders the application of carbon-ceramic brake discs in rail transportation. The full carbon-ceramic brake disc body involved in this application has a base material of carbon-ceramic composite material and a wear-resistant ceramic coating prepared on the surface.

[0072] In one embodiment, the material of the wear-resistant ceramic coating is SiC, and the thickness is 1.5-2.5 mm.

[0073] In one embodiment, if Fig.10 As shown, the wear-resistant ceramic coating adopts a retreat design during preparation.

[0074] Specifically, the wear-resistant ceramic coating does not completely cover the friction surface of the disc body, but adopts a retreat design. The remaining thickness of the ceramic coating can be visually identified, and the thickness of the ceramic coating is used as the wear limit of the brake disc. The ceramic coating has the function of stabilizing the friction coefficient and reducing the wear of the brake pad. The design using the coating thickness as the wear limit can ensure the stability of the friction and wear performance during the service life of the brake disc. The existing carbon-ceramic composite brake disc with ceramic coating has a ceramic coating that completely covers the friction surface of the disc body. The remaining thickness of the ceramic coating is difficult to identify and there is no obvious wear limit marking. From the perspective of the stability of the brake disc's performance and the operability of overhaul and maintenance, this application can achieve that the friction and wear performance of the brake disc remains stable within the wear limit, and the remaining wear life of the brake disc can be easily identified during maintenance.

[0075] Fig.11 FIG. 1 is an exploded view of the assembly relationship of a full carbon-ceramic wheel-shaped brake disc provided in an embodiment of the present application. Fig.11 As shown, the full carbon ceramic wheel mounted brake disc also includes: a positioning pin 3;

[0076] The full carbon ceramic brake disc body 1 is provided with a positioning groove, and the positioning pin 3 passes through the mounting hole of the wheel 100 and is inserted into the positioning groove to fix the full carbon ceramic brake disc body 1 on both sides of the wheel 100. The assembly relationship of the positioning pin 3, the first brake disc body 101, the second brake disc body 102 and the wheel 100 is as shown in FIG. Fig.12 shown.

[0077] Specifically, the positioning pin 3 passes through the positioning pin installation hole on the spoke plate of the wheel 100, and both ends are inserted into the positioning grooves of the disc body to realize the positioning of the disc body on the wheel 100.

[0078] Fig.13 : is a schematic diagram of the structure of the positioning pin 3 provided in an embodiment of the present application. Fig.13As shown, the body of the positioning pin 3 includes two positioning parts; a through hole 31 is provided at the central axis of the positioning part, and a slit-shaped opening 32 communicating with the through hole 31 is provided on the side of the body.

[0079] Specifically, since the high temperature generated by braking is transmitted to the locating pin 3 through the disc body, the existing locating pin 3 structure will cause the locating pin 3 to undergo thermal expansion deformation and expand in the locating pin 3 mounting hole of the wheel 100, making the locating pin 3 difficult to remove during disassembly and maintenance.

[0080] In order to solve the above problem, a through hole 31 is processed at the central axis of the two locating parts of the locating pin 3, and a slit-shaped opening 32 is processed in one direction between the through hole 31 and the outer shell of the locating part, realizing the elastic design of center drilling and single-sided opening, so that the locating pin 3 has a certain elasticity, so that the brake disc locating pin 3 can be smoothly removed during disassembly and maintenance.

[0081] In addition, the present application also provides a vehicle having a full-carbon ceramic wheel-mounted brake disc provided by any of the above embodiments, wherein the full-carbon ceramic wheel-mounted brake disc is arranged on a wheel 100 to brake the wheel 100.

[0082] The present application provides a full-carbon-ceramic wheel-mounted brake disc and a vehicle using the same, which comprises at least two full-carbon-ceramic brake disc bodies and fasteners; the full-carbon-ceramic brake disc bodies are fixed to both sides of the wheel by the fasteners to clamp the wheel; the full-carbon-ceramic brake disc body comprises a friction ring and a plurality of heat dissipation ribs; the heat dissipation ribs are arranged on the supporting surface of the friction ring, each of the heat dissipation ribs is provided with at least two circumferential air-flow passages, and radial air-flow passages are provided between each of the heat dissipation ribs, thereby achieving the characteristics of lightweight, high heat capacity and low wind resistance, ensuring a reliable fastening connection, facilitating maintenance and facilitating replacement and verification on existing vehicles, and improving overall performance and safety.

[0083] Among them, the wheel-mounted brake disc body is made of all-carbon-ceramic composite material, which reduces weight by more than 50% compared with traditional steel brake discs, and reduces weight by more than 20% compared with carbon-ceramic brake discs with steel support structures; the wheel-mounted brake disc body is designed based on a multi-objective optimization of aerodynamics and multi-physics field coupling simulation, including "hammer-shaped" heat dissipation ribs and unique friction ring / heat dissipation rib thickness, so that the wheel-mounted brake disc body has the characteristics of high heat capacity and low pumping power, effectively reducing continuous braking temperature rise and energy loss caused by pumping power; the friction surface of the wheel-mounted brake disc body adopts a wear-resistant ceramic coating design with identifiable thickness, and the wear-resistant functional coating thickness is used as the wear limit structure, which can ensure the wear and tear condition of the brake disc. It can be easily identified with the naked eye, and while maintaining the same maintenance habits as existing brake discs, the friction and wear of the brake discs can be guaranteed to remain stable during their service life; the fasteners have thermal deformation coordination capabilities, which can effectively prevent the attenuation of the fastening connection preload caused by the low thermal expansion coefficient of the carbon ceramic material due to high braking temperature, thereby ensuring the reliability of the fastening connection; the locating pin adopts an elastic opening structure, which can prevent the locating pin from expanding and deforming in the wheel mounting hole due to braking heat, which is conducive to disassembly and replacement during maintenance; the full carbon ceramic wheel-mounted brake disc has the same interface size as the existing high-speed EMU wheel-mounted brake disc, which can realize the replacement of existing steel brake discs, and facilitate the use of existing vehicle resources to replace and verify the full carbon ceramic wheel-mounted brake disc.

[0084] In the description of this specification, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", etc. are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, "multiple" means two or more.

[0085] The descriptions with reference to the terms "one embodiment", "a specific embodiment", "some embodiments", "for example", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. The order of steps involved in each embodiment is used to schematically illustrate the implementation of the present application, and the order of steps therein is not limited and may be appropriately adjusted as needed.

[0086] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood by specific circumstances.

[0087] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present application. It should be understood that the above description is only a specific embodiment of the present application and is not intended to limit the scope of protection of the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A full carbon ceramic wheel mounted brake disc, characterized in that: include: At least two full carbon-ceramic brake discs; The full carbon ceramic brake disc body is fixed on both sides of the wheel to clamp the wheel; The full carbon ceramic brake disc body includes a friction ring and a plurality of heat dissipation ribs; the heat dissipation ribs are arranged on the supporting surface of the friction ring, each of the heat dissipation ribs is provided with at least two circumferential air flow channels, and radial air flow channels are provided between each of the heat dissipation ribs.

2. The full carbon ceramic wheel mounted brake disc according to claim 1, characterized in that: The full carbon ceramic brake disc body comprises: a first brake disc body and a second brake disc body; the first brake disc body and the second brake disc body are fixed to both sides of the wheel by a fastener; the fastener comprises a bolt, a bolt sleeve, a gasket and a nut; The bolt passes through the bolt sleeve, the first brake disc body, the wheel, the second brake disc body and the gasket in sequence, and is fastened to the nut.

3. The full carbon ceramic wheel mounted brake disc according to claim 2, characterized in that: The material of the bolt is martensitic stainless steel or alloy steel with a low thermal expansion coefficient; the material of the bolt sleeve and the gasket is austenitic steel with a high thermal expansion coefficient.

4. The full carbon ceramic wheel mounted brake disc according to claim 1, characterized in that: The thickness of the friction ring is 31 mm to 37 mm, and the thickness of the heat dissipation rib is 15.5 mm to 9.5 mm.

5. The full carbon ceramic wheel mounted brake disc according to claim 4, characterized in that: The thickness of the friction ring and the thickness of the heat dissipation rib are calculated by a single-variable multi-objective optimization model.

6. The full carbon ceramic wheel mounted brake disc according to claim 1, characterized in that: A wear-resistant ceramic coating is prepared on the friction surface of the friction ring.

7. The full carbon ceramic wheel mounted brake disc according to claim 6, characterized in that: The wear-resistant ceramic coating is prepared by adopting a retreat design.

8. The full carbon ceramic wheel mounted brake disc according to claim 1, characterized in that: Also includes: Positioning pins; The full carbon ceramic brake disc body is provided with a positioning groove, and the positioning pin passes through the mounting hole of the wheel and is inserted into the positioning groove to fix the full carbon ceramic brake disc body on both sides of the wheel.

9. The full carbon ceramic wheel mounted brake disc according to claim 8, characterized in that: The body of the positioning pin comprises two positioning parts; a through hole is arranged at the central axis of the positioning part, and a slit-shaped opening communicating with the through hole is arranged at the side of the body.

10. The full carbon ceramic wheel mounted brake disc according to claim 1, characterized in that: The top view of the heat dissipation rib is in the shape of a mallet.

11. A vehicle, characterized in that: The vehicle has a full-carbon ceramic wheel-mounted brake disc according to any one of claims 1 to 10, and the full-carbon ceramic wheel-mounted brake disc is arranged on a wheel to brake the wheel.

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