Train brake pad friction block texture structure testing device

Abstract

The utility model provides a testing device for a train brake pad friction block texture structure, belongs to the technical field of brake pad friction blocks, and aims to solve the stick-slip vibration phenomenon occurring when a high-speed train is braked. In the prior art, a large number of tests and debugging are needed and wide popularization is difficult to realize when the stick-slip vibration is inhibited by integrally changing the property of a friction block or installing a viscoelastic damper and the like. In the utility model, different textures are designed on the surface of the brake pad friction block; the surface texture design based on the friction blocks is adopted to restrain the stick-slip vibration phenomenon of the train braking system, the method is a method for actively restraining the stick-slip vibration from the source, the structure of the braking system does not need to be modified or increased or decreased, and therefore the operation and maintenance cost of a train is not increased, and popularization is easier to achieve.

Description

Technical Field

[0001] The utility model belongs to the technical field of brake pad friction blocks, and in particular relates to a testing device for the texture structure of a train brake pad friction block. Background Art

[0002] High-speed trains achieve train braking and speed control through the friction between the brake pad friction block and the brake disc. However, at low speeds (<5 km / h), disc / block friction braking can easily cause stick-slip vibration in the braking system. Stick-slip vibration not only causes abnormal wear and rupture of the friction block, threatening the braking safety of the train, but also produces braking noise, affecting the riding experience and the normal life of residents along the way, thus causing many complaints. Therefore, taking measures to reduce or suppress stick-slip vibration under friction braking is of great significance to improving the safe operation of trains. Existing methods such as changing the shape, material, and installation direction of the brake pad friction block, or adding viscoelastic dampers to the friction block to suppress the stick-slip vibration of the braking system often require a lot of testing and debugging, and for different train types and operating conditions, different system structures and parameter settings need to be considered for matching, which is costly and difficult to promote widely. Utility Model Content

[0003] In view of this, the utility model provides a testing device for the texture structure of the friction block of a train brake pad to solve the problem that the existing method of changing the properties of the friction block as a whole or installing a viscoelastic damper often requires a large amount of testing and debugging, and for different train types and operating conditions, different system structures and parameter settings need to be considered, which results in high cost and is difficult to promote widely.

[0004] The technical solution adopted by the utility model is as follows:

[0005] A train brake pad friction block texture structure, wherein the brake pad friction block surface is provided with a texture texture.

[0006] Preferably, the texture is a rectangular groove texture, a trapezoidal groove texture or a V-shaped groove texture.

[0007] Preferably, the texture is a radial rectangular groove texture, a grid-like rectangular groove texture or a corrugated rectangular groove texture.

[0008] A testing device for a train brake pad friction block texture structure, comprising a fixture, a friction block, a brake disc and a driving device;

[0009] The brake disc is arranged on a driving device, and the driving device is used to drive the brake disc to rotate;

[0010] The friction block is installed on the fixture, and a gasket is installed between the fixture and the friction block. The fixture clamps or loosens the brake disc through the friction block.

[0011] Preferably, the driving device includes an electric motor, an output end of the electric motor is connected to a clutch, an output end of the clutch is connected to a flywheel device, an output end of the flywheel device is connected to a torque sensor, and an output end of the torque sensor is connected to a brake disc.

[0012] Preferably, the clamp includes a bracket and a rotating assembly located on both sides of the bracket, the rotating assembly includes a caliper and a brake pad back plate, the middle part of the caliper is hinged to the bracket, the brake pad back plate is arranged at one end of the caliper, and a fixed back plate is installed on the brake pad back plate through a retaining spring and a fixing pin, a friction block is installed at the end of the fixed back plate, and the gasket is sleeved on the fixing pin; the rotating assembly also includes a power assembly for driving the caliper to move; the power assembly includes a cylinder, the bottom of the cylinder is hinged to the ground, and the output end of the cylinder is hinged to the end of the caliper.

[0013] In this technical solution, the brake disc is located between the friction blocks on both sides, and the power assembly includes a cylinder. When the brake disc needs to be clamped, the cylinder is started to drive the two calipers on the bracket to rotate around the hinge point with the bracket until the friction blocks on the back plate of the brake pad are close to clamp the brake disc.

[0014] Preferably, the brake pad friction block gasket material is manganese-copper damping alloy, cast iron, nitrile rubber, silicone rubber, 304 stainless steel, 60SiMnA or 51CRV4.

[0015] Preferably, the brake pad friction block shim thickness is determined according to the friction block size.

[0016] In summary, due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0017] 1. The utility model suppresses stick-slip vibration by texturing the surface of the friction block and improving the connection method of the brake pad friction block. It is a method that actively suppresses stick-slip vibration from the source, and does not require modification or addition or subtraction of the structure of the braking system. Therefore, it does not increase the operation and maintenance cost of the train and is easier to promote.

[0018] 2. In the present utility model, the advantages of using surface texture to suppress stick-slip vibration during braking are mainly as follows: first, the surface texture morphology is controllable, and a variety of processing methods can be used to prepare texture morphologies of different shapes and arrangements. Second, the surface texture can collect wear debris during the friction process to avoid the accumulation of wear debris on the friction interface, thereby improving the interface friction vibration behavior. Third, the surface texture can change the interface contact state and stress distribution, and its periodic changes will affect the stick-slip vibration behavior. Fourth, the designed surface texture can improve the friction and wear characteristics between the friction pairs to a certain extent, thereby reducing the intensity of stick-slip vibration.

[0019] 3. In the present invention, changing the material of the gasket can optimize the contact pressure distribution between the friction block and the brake disc and extend the service life of the friction block. Second, the appropriate gasket material can absorb part of the impact force and enhance driving stability. Third, changing the gasket thickness can optimize the distance between the friction block and the brake disc, greatly suppressing the unstable vibration caused by friction self-excited vibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be described by way of examples with reference to the accompanying drawings, in which:

[0021] Figure 1.1 It is a structural schematic diagram of the first embodiment of the utility model.

[0022] Figure 1.2 yes Figure 1.1 AA section enlarged view.

[0023] Figure 1.3 It is a schematic diagram of the installation of a friction block with a rectangular groove texture on the surface on a brake pad.

[0024] Figure 2.1 It is a structural schematic diagram of the second embodiment of the present utility model.

[0025] Figure 2.2 yes Figure 2.1 AA section enlarged view.

[0026] Figure 2.3 It is a schematic diagram of the installation of a friction block with a trapezoidal groove texture on the brake pad.

[0027] Figure 3.1 It is a structural schematic diagram of the third embodiment of the present utility model.

[0028] Figure 3.2 yes Figure 3.1 AA section enlarged view.

[0029] Figure 3.3 It is a schematic diagram of the installation of a friction block with a V-shaped groove texture on the surface on a brake pad.

[0030] Figure 4.1It is a structural schematic diagram of the fourth embodiment of the present utility model.

[0031] Figure 4.2 yes Figure 4.1 AA section enlarged view.

[0032] Figure 4.3 It is a schematic diagram of the installation of a friction block with a radial groove texture on the surface on a brake pad.

[0033] Figure 5.1 It is a structural schematic diagram of the fifth embodiment of the present utility model.

[0034] Figure 5.2 yes Figure 5.1 AA section enlarged view.

[0035] Figure 5.3 It is a schematic diagram of the installation of a friction block with a grid-like groove texture on the surface on a brake pad.

[0036] Figure 6.1 It is a structural schematic diagram of embodiment 6 of the present utility model.

[0037] Figure 6.2 yes Figure 6.1 AA section enlarged view.

[0038] Figure 6.3 It is a schematic diagram of the installation of a friction block with a corrugated groove texture on the brake pad.

[0039] Figure 7.1 It is a schematic diagram of the electric spark cutting machine in the utility model.

[0040] Figure 8.1 It is a schematic diagram of the overall device of the utility model.

[0041] Figure 9.1 It is a schematic diagram of the structure of the gasket in Example 11 of the utility model.

[0042] Figure 10.1 It is the time domain curve of the vibration signal of the friction block with original shape.

[0043] Figure 10.2 It is the time domain curve of the vibration signal of the friction block on the textured surface.

[0044] Figure 11.1 It is the time domain curve of the vibration signal of the friction system of the cast iron gasket.

[0045] Figure 11.2 It is the time domain curve of the vibration signal of the friction system of the silicone material gasket.

[0046] Figure 12.1 It is the time domain curve of the vibration signal of the friction system with a gasket thickness of 1 mm.

[0047] Figure 12.2 It is the time domain curve of the vibration signal of the friction system with a gasket thickness of 1.25 mm.

[0048] Attached photos

[0049] 1-control system, 2-frequency conversion motor, 3-clutch, 4-flywheel device, 5-torque sensor, 6-laser vibrometer, 7-bracket, 8-caliper, 9-friction block, 10-brake pad back plate, 11-brake disc, 12-three-axis vibration acceleration sensor, 13-signal acquisition system, 14-fixed back plate, 15-gasket, 16-circlip, 17-fixing pin, 18-cylinder, 19-reel, 20-guide wheel, 21-molybdenum wire, 22-cutting table, 23-processing fixture. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0051] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0052] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features thereof may be combined with each other.

[0053] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0054] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0055] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features thereof may be combined with each other. Example 1

[0056] Figure 1.1 , Figure 1.2 , Figure 1.3 The first embodiment of the utility model is shown, in which the surface of the hexagonal brake pad friction block 9 for suppressing the stick-slip vibration of the high-speed train braking system is processed with a uniformly arranged rectangular groove texture. α 0°~90°; groove width w 0.1~6.0 mm, depth h 0.1~4.0mm; groove spacing i 3.0~15.0 mm; Number of grooves n By groove spacing i Determined together with the size of the friction block 9.

[0057] Figure 10.1 , Figure 10.2 These are the stick-slip vibration signals of the friction block with the original morphology and the friction block 9 with the textured surface in the stable stage. Compared with the friction block without micro-texture, the vibration signal of the friction system of the friction block 9 with groove texture on the surface fluctuates more smoothly overall, without violent fluctuations, and its vibration is significantly reduced, the vibration amplitude is reduced by more than 70%, and the proportion of adhesion time is reduced by more than 5%. Example 2

[0058] Figure 2.1 , Figure 2.2 , Figure 2.3 The second embodiment of the utility model is shown, in which the surface of the hexagonal brake pad friction block 9 for suppressing the stick-slip vibration of the high-speed train braking system is processed with a uniformly arranged trapezoidal groove texture. α 0°~90°; groove width w 0.1~6.0 mm, depth h0.1~4.0mm; the angle of the trapezoidal groove θ 1 0°~180°; groove spacing i 3.0~15.0 mm; Number of grooves n By groove spacing i Determined together with the size of the friction block 9. Example 3

[0059] Figure 3.1 , Figure 3.2 , Figure 3.3 The third embodiment of the utility model is shown, in which the surface of the hexagonal brake pad friction block for suppressing the stick-slip vibration of the high-speed train braking system is processed with a uniformly arranged V-shaped groove texture. α 0°~90°; Width w 0.1~6.0 mm, depth h 0.1~4.0mm; the angle of the V-shaped groove θ 2 0°~90°; groove spacing i 3.0~15.0 mm; Number of grooves n By groove spacing i Determined together with the size of the friction block 9. Example 4

[0060] Figure 4.1 , Figure 4.2 , Figure 4.3 The fourth embodiment of the utility model is shown, in which the surface of the hexagonal brake pad friction block 9 used to suppress the stick-slip vibration of the high-speed train braking system is processed with a radial rectangular groove texture. w 0.1~6.0 mm, depth h 0.2~4.0 mm; spacing arc δ is the groove width w 2 to 5 times of. Example 5

[0061] Figure 5.1 , Figure 5.2 , Figure 5.3 The fifth embodiment of the utility model is shown, in which the surface of the hexagonal brake pad friction block 9 for suppressing the stick-slip vibration of the high-speed train braking system is processed with a grid-like rectangular groove texture. The grid is formed by the intersection of two groups of parallel rectangular grooves; in each group of structures, the groove width is w 0.1~6.0 mm, depth h 0.1~4.0 mm; groove spacing i 3.0~15.0 mm; the number of grooves in each group n By groove spacingi and the size of the friction block 9; the angle between the two sets of grooves γ It is 0°~90°. Example 6

[0062] refer to Figure 6.1 , Figure 6.2 , Figure 6.3 The sixth embodiment of the utility model is that the surface of the hexagonal brake pad friction block 9 used to suppress the stick-slip vibration of the high-speed train braking system is processed with a corrugated rectangular groove texture. The texture is centered on the center of the friction block 9 and is spaced at a distance of i Processing is performed layer by layer outward; Groove width w 0.1~6.0 mm, depth h 0.1~4.0mm; groove spacing i 3.0~15.0 mm; Number of grooves n By groove spacing i Determined together with the size of the friction block 9. Example 7

[0063] This embodiment provides a method for processing a train brake pad friction block texture structure, comprising:

[0064] Step A: fix the friction block 9, and process the surface of the friction block 9 according to a preset texture structure by an electric spark cutting machine;

[0065] Step B: Clean the surface of the friction block 9 after processing to eliminate the influence of friction interface contaminants on the test results;

[0066] Step C: grinding the cleaned surface of the friction block 9 to ensure that the surface of the friction block 9 has a similar surface roughness value;

[0067] Step D: ultrasonically cleaning the surface of the ground friction block 9 to remove surface impurities;

[0068] Step E: drying the friction block 9 in an oven for 15 minutes.

[0069] In this embodiment, Figure 7.1 As shown, the electric spark cutting machine specifically includes a reel 19, a guide wheel 20, a molybdenum wire 21, a cutting table 22 and a processing fixture 23. The molybdenum wire 21 has a wire diameter of 200 μm. The molybdenum wire 21 is stored by the reel 19 and guided by the guide wheel 20. The fixture is used to clamp the friction block 9. During processing, the friction block 9 is cut by the molybdenum wire 21, and different textures are processed by moving the cutting table 22. Example 8

[0070] In this embodiment, reference Figure 1.3, is a three-dimensional structural diagram of the installation method of the friction block 9 with groove texture on the surface on the brake pad. The method adopted is floating installation. First, it has strong stability and reduces the possibility of the friction block 9 falling off or shifting due to vibration or impact. In addition, the floating installation has a good braking effect and can reduce noise. Finally, the floating installation can also reduce the problems of cracks, ruptures and defects of the friction block 9, thereby extending the service life of the friction block 9 and the entire brake pad. Example 9

[0071] like Figure 8.1 As shown, this embodiment proposes a testing device for a train brake pad friction block, including a fixture, a friction block 9, a brake disc 11 and a driving device; the friction block is installed on the fixture, and a gasket is installed between the fixture and the friction block, and the fixture clamps or loosens the brake disc 11 through the friction block 9.

[0072] In this embodiment, the brake pad friction block structure includes a friction block 9, a fixed back plate 14, a gasket 15, a retaining spring 16 and a fixing pin 17; the friction block 9 is fixedly connected to the fixed back plate 14, a gasket 15 and a retaining spring 16 are installed under the fixed back plate 14, the fixed back plate 14 is connected to the fixing pin 17, and is fixed to the brake pad back plate by the retaining spring 16.

[0073] In this embodiment, the driving device includes a variable frequency motor 2, the output end of the variable frequency motor 2 is connected to a clutch 3, the output end of the clutch 3 is connected to a flywheel device 4, the output end of the flywheel device 4 is connected to a torque sensor 5, and the output end of the torque sensor 5 is connected to the brake disc 11.

[0074] In this embodiment, the clamp includes a bracket 7 and two rotating components on both sides, the bracket 7 fixes the two rotating components on both sides, the rotating components include a caliper 8 and a brake pad back plate 10, and the brake pad back plate 10 is mounted with a friction block 9 through a retaining spring 16; the rotating component also includes a power component for driving the caliper 8 to move; the power component includes a cylinder 18, the bottom of the cylinder 18 is hinged to the ground, and the output end of the cylinder 18 is hinged to the caliper 8. When it is necessary to clamp the brake disc 11 located between the friction blocks 9 on both sides, the cylinder 18 can be started to drive the caliper 8 on the bracket 7 to rotate around the hinge point with the bracket as the center until the friction blocks 9 on the brake pad back plate 10 are close to clamp the brake disc 11. Example 10

[0075] This embodiment proposes a method for testing the texture structure of a brake pad friction block based on embodiment 9, including:

[0076] Step 1: Clamp the brake disc 11 by a clamp so that the friction blocks 9 on the brake pad back plates 10 on both sides are in contact with the brake disc 11;

[0077] Step 2: Start the variable frequency motor 2 through the control system 1, and the variable frequency motor 2 drives the flywheel device 4 through the clutch 3 to make the brake disc 11 reach the test set speed, then the clutch 3 is disconnected, and the brake disc 11 completes braking under the action of the brake pad friction block;

[0078] In step 2, during the braking process of the brake disc 11, a three-axis vibration acceleration sensor 12 installed on the caliper 8 and a non-contact laser vibrometer 6 are used to collect the tangential vibration velocity signal of the friction block during the friction process, and the data is collected and stored through the signal acquisition system 13. Embodiment 11

[0079] like Figure 9.1 As shown, this embodiment proposes a method for improving the connection structure of the brake pad friction block on the basis of embodiment 9, and achieves the effect of suppressing stick-slip vibration by changing the gasket 15 installed between the fixture and the friction block 9 (the friction block in embodiment 1 is used) during the test. The gasket 15 includes manganese copper damping alloy, cast iron, nitrile rubber, silicone rubber, 304 stainless steel, 60SiMnA, 51CRV4; the gasket 15 has a thickness of T Determined to be 0.5-5.0 mm according to the size of the friction block.

[0080] Figure 11.1 , Figure 11.2 These are the stick-slip vibration signals of the two friction systems, cast iron gasket (original material) and silicone gasket, in the stable stage. Compared with the original cast iron gasket, the unstable vibration signal of the silicone gasket friction system gradually weakened or even disappeared in the adhesion stage, and the unstable vibration in the sliding stage was significantly weakened, with its vibration amplitude significantly reduced by about 68%, and the adhesion time reduced by about 50%.

[0081] Figure 12.1 , Figure 12.2 They are the stick-slip vibration signals of two friction systems in the stable stage, one is a silicone gasket with a thickness of 1 mm (original thickness) and the other is a gasket with a thickness of 1.25 mm. Compared with the gasket with a thickness of 1 mm, the vibration amplitude of the friction system with a gasket thickness of 1.25 mm is significantly reduced, by about 53%, and the proportion of adhesion time is significantly reduced, by about 47%.

[0082] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A testing device for the texture structure of a train brake pad friction block, characterized in that: It comprises a clamp, a friction block (9), a brake disc (11) and a driving device; The surface of the brake pad friction block is provided with a texture; The brake disc (11) is arranged on a driving device, and the driving device is used to drive the brake disc (11) to rotate; The friction block (9) is mounted on a fixture, and a gasket (15) is installed between the fixture and the friction block (9), and the fixture clamps or loosens the brake disc (11) through the friction block (9); The clamp comprises a bracket (7) and a rotating assembly located on both sides of the bracket (7), the rotating assembly comprises a caliper (8) and a brake pad back plate (10), the middle part of the caliper (8) is hinged to the bracket (7), the brake pad back plate (10) is arranged at one end of the caliper (8), and a fixed back plate (14) is installed on the brake pad back plate (10) through a retaining spring (16) and a fixing pin (17), a friction block (9) is installed at the end of the fixed back plate (14), and the gasket (15) is sleeved on the fixing pin (17); The rotating assembly also includes a power assembly for driving the caliper (8) to move; The power assembly comprises a cylinder (18), the bottom of the cylinder (18) is hinged to the ground, and the output end of the cylinder (18) is hinged to the end of the caliper (8).

2. A testing device for the texture structure of a train brake pad friction block according to claim 1, characterized in that: The drive device comprises a variable frequency motor (2), the output end of the variable frequency motor (2) is connected to a clutch (3), the output end of the clutch (3) is connected to a flywheel device (4), the output end of the flywheel device (4) is connected to a torque sensor (5), and the output end of the torque sensor (5) is connected to a brake disc (11).

3. A testing device for the texture structure of a train brake pad friction block according to claim 1, characterized in that: The texture is a rectangular groove texture, a trapezoidal groove texture or a V-shaped groove texture.

4. A testing device for the texture structure of a train brake pad friction block according to claim 1, characterized in that: The texture is a radial rectangular groove texture, a grid-like rectangular groove texture or a corrugated rectangular groove texture.

Images