Spherical floating brake pad for motor train unit

Abstract

A kind of spherical floating type EMU brake shoe, including left brake shoe and right brake shoe, left brake shoe and right brake shoe are left-right symmetrical structure;Left, right brake shoe includes left, right steel back, friction block and spring buckle respectively;Friction surface of friction block is octagonal shape, and friction block is installed on left steel back and right steel back by spring buckle respectively;Adjusting support is arranged between each friction block and left steel back or right steel back;Friction block and adjusting support, adjusting support and left steel back or right steel back are spherical surface cooperation between each other.The utility model discloses through spherical floating structure and the elasticity of spring buckle, let friction block can self-adapting adjustment, has guaranteed that friction surface and brake disc surface fully adhere, effectively reduce the occurrence of eccentric wear phenomenon;By adopting the way of spherical floating cooperation, can effectively solve the problem of dished spring edge to the scratch of backplate surface, ensure that the sustained and effective of floating design.

Description

Technical Field

[0001] This utility model relates to a brake pad for high-speed trains, and more particularly to a spherical floating brake pad for high-speed trains. Background Technology

[0002] Current high-speed trains generally employ disc braking systems, which convert the train's enormous kinetic energy into heat energy through friction between the brake pads and the brake disc, reducing the train's speed and ensuring that the train can stop within a safe distance. The brake pads are the most critical actuator in the high-speed train's braking system. They not only require a stable coefficient of friction, wear resistance, and high-temperature resistance, but also must ensure an effective friction area between the pads and the brake disc to reduce braking instability, abnormal wear, chipping, and other phenomena caused by uneven wear, thereby improving the braking efficiency and service life of the brake pads.

[0003] Existing high-speed train brake pads mostly use an elastic floating structure with disc springs as the elastic element and a two-stage spherical floating structure with triangular supports as rigid levers.

[0004] CN104455105A discloses a floating brake pad, including a back plate; a plurality of friction blocks disposed on the back plate; a disc spring disposed between the friction blocks and the back plate; and a retaining spring for buoyantly connecting the friction blocks to the first back plate; the back plate is formed with a positioning groove, and the disc spring is disposed in the positioning groove.

[0005] Disc springs effectively absorb the impact and vibration during braking, using their elasticity to press the friction blocks firmly against the brake disc during low-speed or initial high-speed braking. However, during high-speed braking, as the braking process continues and the temperature of the friction surface rises, a significant amount of heat is transferred to other structural components through heat conduction. Disc springs are thin-plate structures, typically fitting with other components in a line-surface manner. When a large amount of heat is transferred through the disc spring, the poor heat dissipation path leads to heat accumulation within the spring. Typically, as temperature increases, the tensile strength and yield strength of the material decrease significantly. The combined effects of pressure and high temperature cause disc springs to undergo plastic deformation, resulting in reduced elasticity or even failure, preventing the friction blocks from effectively adhering to the brake disc. The hardness of disc springs is higher than other structural components; during braking, their sharp edges continuously scrape the surfaces of other components, especially the spherical part of the backing plate, easily forming grooves. This causes the friction blocks to lose their elastic floating function, affecting the braking performance of the brake pads and reducing their service life due to uneven wear of the friction blocks.

[0006] CN221990819U discloses a high-speed train braking technology, aiming to provide a high-speed train brake pad. The key technical point is that it includes a large steel backing, which is composed of a large steel backing L and a large steel backing R. A friction unit is provided on the large steel backing and connected to the large steel backing through a triangular bracket. The friction unit is fixedly connected to the large steel backing through a snap ring. The friction unit is formed by sintering a small steel backing and a powder metallurgy sintered layer in a high-temperature sintering furnace.

[0007] In the two-stage spherical floating structure, each set of friction blocks simultaneously rotates and oscillates around the center of the triangular support spherical surface assembled within that set. One or two friction blocks will contact the brake disc surface first, and the stress distribution on the friction surface after engagement is not very uniform, which can easily cause uneven wear of the brake pads and reduce the service life of the brake pads. Utility Model Content

[0008] The technical problem to be solved by this utility model is to overcome the above-mentioned deficiencies of the prior art and provide a spherical floating EMU brake pad that can effectively solve the problem of scratching the back plate surface by the edge of the disc spring and can effectively reduce the phenomenon of uneven wear.

[0009] The technical solution adopted by this utility model to solve its technical problem is as follows: a spherical floating EMU brake pad, including a left brake pad and a right brake pad, the left brake pad and the right brake pad having a left-right symmetrical structure; the left brake pad includes a left steel back, a friction block and a spring clip; the right brake pad includes a right steel back, a friction block and a spring clip; the friction block includes a back plate and a friction body, the friction surface of the friction block is octagonal, and the friction block is installed on the left steel back and the right steel back through the spring clip; an adjustment bracket is provided between each friction block and the left steel back or the right steel back; the friction block and the adjustment bracket are spherically fitted to form a primary spherical floating structure; the adjustment bracket and the left steel back or the right steel back are spherically fitted to form a secondary spherical floating structure.

[0010] Furthermore, the front side of the adjustment bracket is provided with a concave spherical surface A and a limiting boss, and the back side of the adjustment bracket is provided with a convex spherical surface B and an anti-rotation pin.

[0011] Furthermore, the number of the limiting bosses is two, and the shape of the limiting bosses is rectangular.

[0012] Furthermore, a convex spherical surface C and a pin are provided at the center of the back plate.

[0013] Furthermore, the concave spherical surface A mates with the convex spherical surface C, the limiting boss is in clearance fit with the edge of the back plate, the convex spherical surface B mates with the concave spherical surface D of the left steel back or the right steel back, and the anti-rotation pin is in clearance fit with the anti-rotation hole of the left steel back or the right steel back.

[0014] Furthermore, an annular groove is provided at the top of the pin; the inner ring surface of the spring buckle mates with the annular groove, and the outer ring surface of the spring buckle mates with the buckle countersunk hole of the left steel back or the right steel back.

[0015] Furthermore, nine friction blocks are installed on the left brake plate and nine friction blocks are installed on the right brake plate.

[0016] Furthermore, the nine friction blocks on the left or right brake plate are arranged in four rows along the radial direction of the left or right steel backing, with a spacing of 7-12mm between rows. This forms a good and unobstructed channel for chip removal, ventilation, and heat dissipation.

[0017] Furthermore, the friction block is formed by sintering the back plate and the friction body together using powder metallurgy.

[0018] Furthermore, the dovetail of the left or right steel back is integrally cast with the steel back, and the left and right steel backs have a symmetrical structure.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] (1) The structure of this utility model utilizes the double-layer spherical floating structure formed by the cooperation of the convex spherical surface C of the friction block back plate and the concave spherical surface A of the adjustment bracket and the cooperation of the convex spherical surface B of the adjustment bracket and the concave spherical surface D of the steel back plate, as well as the elasticity of the spring buckle, to realize the adaptive floating of the friction body, which fits tightly against the brake disc surface and can achieve a good braking effect.

[0021] (2) The structure of this utility model replaces the disc spring with an adjustment bracket, and changes the line-to-surface fit to a surface-to-surface fit. The heat transfer path is smoother, the heat dissipation performance is more efficient, and the parts will not fail due to heat accumulation, thus ensuring the continuous effectiveness of the floating mechanism.

[0022] (3) Each friction block of this utility model is matched with an adjustment bracket to eliminate the deviation generated by the friction blocks during the sway adjustment. According to the finite element software simulation comparison, the stress distribution of the friction surface is more uniform than that of the triangular support structure. The maximum stress value is only 30%-40% of the stress value of the friction surface of the triangular support structure, which reduces the wear phenomenon of the brake pad and improves the service life of the brake pad. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of the spherical floating EMU brake pad of this utility model;

[0024] Figure 2 for Figure 1 The figure shown is a partial cross-sectional view of Embodiment 1 of this utility model;

[0025] Figure 3 for Figure 1The diagram shows the front structural diagram of the steel backing of Embodiment 1 of this utility model;

[0026] Figure 4 for Figure 1 The diagram shows the reverse side structure of the steel backing in Embodiment 1 of this utility model.

[0027] Figure 5 for Figure 1 The diagram shown is a schematic diagram of the friction block structure of Embodiment 1 of this utility model;

[0028] Figure 6 for Figure 1 The diagram shown is a schematic diagram of the spring buckle structure of Embodiment 1 of this utility model;

[0029] Figure 7 for Figure 1 The diagram shown is a schematic diagram of the front and side structure of the adjustment bracket in Embodiment 1 of this utility model;

[0030] Figure 8 for Figure 1 The diagram shows the back side structure of the adjustment bracket in Embodiment 1 of this utility model. Detailed Implementation

[0031] In the description of this utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the structure of this utility model, 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 limiting the structure of this utility model.

[0032] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0033] Example 1

[0034] See attached document Figure 1-8 This embodiment discloses a spherical floating EMU brake pad, including a left brake pad and a right brake pad, which are symmetrically arranged. The left brake pad includes a left steel back 5, a friction block 4, and a spring clip 2. The right brake pad includes a right steel back 1, a friction block 4, and a spring clip 2. The friction block 4 includes a back plate 41 and a friction body 42. The friction surface of the friction block 4 is octagonal. The friction block 4 is mounted on the left steel back 5 and the right steel back 1 via the spring clip 2. An adjustment bracket 3 is provided between each friction block 4 and the left steel back 5 or the right steel back 1. The friction block 4 and the adjustment bracket 3 are spherically fitted to form a primary spherical floating structure. The adjustment bracket 3 and the left steel back 5 or the right steel back 1 are spherically fitted to form a secondary spherical floating structure.

[0035] The front side of the adjustment bracket 3 is provided with a concave spherical surface A31 and a limiting boss 32, and the back side of the adjustment bracket 3 is provided with a convex spherical surface B33 and an anti-rotation pin 34.

[0036] The number of limiting protrusions 32 is two, and the shape of the limiting protrusions 32 is rectangular.

[0037] The back plate 41 has a convex spherical surface C411 and a pin 412 at its center.

[0038] The concave spherical surface A31 mates with the convex spherical surface C411, the limiting boss 32 is in clearance fit with the edge of the back plate 41, the convex spherical surface B33 mates with the concave spherical surface D11 of the left steel back 5 or the right steel back 1, and the anti-rotation pin 34 is in clearance fit with the anti-rotation hole 12 of the left steel back 5 or the right steel back 1.

[0039] The top of the pin 412 is provided with an annular groove 413; the inner ring surface 21 of the spring buckle 2 cooperates with the annular groove 413, and the outer ring surface 22 of the spring buckle 2 cooperates with the buckle countersunk hole 6 of the left steel back 5 or the right steel back 1.

[0040] Nine friction blocks 4 are installed on the left brake plate, and nine friction blocks 4 are installed on the right brake plate. The nine friction blocks 4 on the left or right brake plate are arranged in four rows along the radial direction of the left steel backing 5 or the right steel backing 1, with a spacing of 7-12mm between the rows. This forms a good and unobstructed channel for chip removal, ventilation, and heat dissipation.

[0041] The friction block 4 is formed by sintering the back plate 41 and the friction body 42 together using powder metallurgy.

[0042] The dovetail of the left steel back 5 or the right steel back 1 is integrally cast with the steel back, and the left steel back 5 and the right steel back 1 have a symmetrical structure.

[0043] This embodiment of the brake pad structure utilizes a double-layer spherical floating structure formed by the cooperation of the convex spherical surface C of the friction block back plate and the concave spherical surface A of the adjusting bracket, and the cooperation of the convex spherical surface B of the adjusting bracket and the concave spherical surface D of the steel back plate, along with the elasticity of the spring clip, to achieve adaptive floating of the friction body, keeping it close to the brake disc surface and achieving good braking effect. This embodiment of the brake pad structure replaces the disc spring with an adjusting bracket, changing the line-to-surface fit to a surface-to-surface fit, resulting in a smoother heat transfer path, more efficient heat dissipation, and preventing component failure due to heat accumulation, thus ensuring the continuous effectiveness of the floating mechanism. Each friction block in this embodiment of the brake pad structure is matched with an adjusting bracket, eliminating deviations caused by the sway adjustment of each friction block. Finite element simulation comparison shows that the stress distribution on the friction surface is more uniform than that of the triangular support structure, with the maximum stress value only 30%-40% of the friction surface stress value of the triangular support structure, reducing brake pad wear from 5mm to 2.5mm and improving the service life of the brake pad.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the specific implementation of the present utility model, so as to facilitate those skilled in the art to reproduce and more fully understand the present utility model, rather than to limit the protection scope of the present utility model; those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present utility model.

Claims

1. A spherical floating type EMU brake pad, comprising a left brake pad and a right brake pad, wherein the left brake pad and the right brake pad are symmetrically arranged; characterized in that, The left brake pad includes a left steel back (5), a friction block (4), and a spring clip (2); the right brake pad includes a right steel back (1), a friction block (4), and a spring clip (2); the friction block (4) includes a back plate (41) and a friction body (42), the friction surface of the friction block (4) is octagonal, and the friction block (4) is installed on the left steel back (5) and the right steel back (1) through the spring clip (2); an adjustment bracket (3) is provided between each friction block (4) and the left steel back (5) or the right steel back (1); the friction block (4) and the adjustment bracket (3) are spherically fitted to form a first-level spherical floating structure; the adjustment bracket (3) and the left steel back (5) or the right steel back (1) are spherically fitted to form a second-level spherical floating structure.

2. The spherical floating EMU brake pad according to claim 1, characterized in that, The front side of the adjustment bracket (3) is provided with a concave spherical surface A (31) and a limiting boss (32), and the back side of the adjustment bracket (3) is provided with a convex spherical surface B (33) and an anti-rotation pin (34).

3. The spherical floating EMU brake pad according to claim 2, characterized in that, The number of the limiting bosses (32) is 2, and the shape of the limiting bosses (32) is rectangular.

4. The spherical floating EMU brake pad according to claim 2 or 3, characterized in that, The back plate (41) is provided with a convex spherical surface C (411) and a pin (412) at the center.

5. The spherical floating EMU brake pad according to claim 4, characterized in that, The concave spherical surface A (31) is fitted with the convex spherical surface C (411), the limiting boss (32) is fitted with the edge of the back plate (41) with a clearance, the convex spherical surface B (33) is fitted with the concave spherical surface D (11) of the left steel back (5) or the right steel back (1), and the anti-rotation pin (34) is fitted with the anti-rotation hole (12) of the left steel back (5) or the right steel back (1) with a clearance.

6. The spherical floating EMU brake pad according to claim 4, characterized in that, The top of the pin (412) is provided with an annular groove (413); the inner ring surface (21) of the spring buckle (2) cooperates with the annular groove (413), and the outer ring surface (22) of the spring buckle (2) cooperates with the buckle countersunk hole (6) of the left steel back (5) or the right steel back (1).

7. The spherical floating EMU brake pad according to any one of claims 1-3, characterized in that, Nine friction blocks (4) are installed on the left brake plate and nine friction blocks (4) are installed on the right brake plate.

8. The spherical floating EMU brake pad according to claim 7, characterized in that, The nine friction blocks (4) on the left or right brake pad are arranged in four columns along the radial direction of the left steel back (5) or the right steel back (1), with a column gap of 7-12 mm.

9. The spherical floating EMU brake pad according to any one of claims 1-3, characterized in that, The friction block (4) is formed by sintering the back plate (41) and the friction body (42) together using powder metallurgy.

10. The spherical floating EMU brake pad according to any one of claims 1-3, characterized in that, The dovetail of the left steel back (5) or the right steel back (1) is integrally cast with the steel back, and the left steel back (5) and the right steel back (1) have a left-right symmetrical structure.

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