Low-floor train side bearing and manufacturing method thereof

Abstract

A low-floor train side bearing sequentially comprises a friction body, an upper metal plate, a first rubber body, a metal partition plate, a second rubber body, a lower metal plate and a plug pin from top to bottom. Two friction bodies are arranged on the upper metal plate, mounting grooves are formed in the positions, corresponding to the friction bodies, of the top face of the upper metal plate, the lower portions of the friction bodies are fixed in the mounting grooves in an interference fit mode, the upper portions of the friction bodies are higher than the surface of the upper metal plate, a gap is formed between the two friction bodies, and chip grooves are formed in the surfaces of the friction bodies. The friction body is made of a polytetrafluoroethylene material; the first rubber body and the second rubber body are formed through rubber vulcanization. The noise generated when the vehicle turns is eliminated, and the riding comfort of passengers is improved; the side bearing local replacement function is achieved, and the side bearing has the advantages of being lower in replacement cost and more convenient to use.

Description

Technical Field

[0001] The invention relates to a low-floor train, in particular to a side bearing of a low-floor train and a manufacturing method thereof. Background Art

[0002] 70% of low-floor trams use side bearings. The function of the side bearings is mainly to bear the vertical load imposed on the bogie by the weight of the car body, provide a certain rotational torque for the car body, and prevent excessive tilting and shaking of the car body and the bogie.

[0003] The existing side bearing device mainly consists of an upper side bearing assembly and a lower side bearing assembly. The lower side bearing assembly consists of a side bearing mounting box and a side bearing. The side bearing is embedded in the side bearing mounting box through a lower plate latch. The side bearing mounting box is mounted on the bolster, and the bolster is mounted on the bogie frame. The friction body of the side bearing is integrally processed with nylon plate material, and two layers of rubber bodies are vulcanized at the bottom of the friction body to play a shock-absorbing role. The two layers of rubber body brackets are connected with a 5mm thick metal partition to play a reinforcing role. Two latches are designed on the lower plate, and the installation of the side bearing in the side bearing mounting box relies on the two latches for positioning. The upper side bearing assembly is mainly a metal side bearing wear plate, which is mounted on the vehicle body chassis by bolts and forms a friction pair with the side bearing.

[0004] The lower side bearing assembly and the upper side bearing assembly can provide the vehicle body and the bogie with vertical load-bearing capacity and a certain rotational torque when the vehicle turns. After a period of use, the existing side bearings have two main disadvantages: one is that the vehicle makes an obvious "squeaking" noise when turning, affecting the comfort of the passengers; the other is that when the side bearing is worn to the limit and needs to be replaced, the side bearing must be replaced as a whole, which has a high replacement cost.

[0005] After analysis and verification, it was found that the existing side bearing friction material is nylon, and the side bearing wear plate is made of stainless steel metal plate 06Cr19Ni10. The friction pair composed of the two has poor self-lubricating performance. When the vehicle turns, the side bearing nylon block and the side bearing wear plate rub and generate heat, causing the fine nylon material to peel off, adhere, sinter and aggregate. The material accumulates on the side bearing wear plate, destroying the smoothness of the side bearing wear plate surface. When the vehicle turns, friction occurs, and the high-frequency vibration of the accumulated material causes noise. Summary of the invention

[0006] The technical problem to be solved by the present invention is a low-floor train side bearing and a manufacturing method thereof, which eliminates the noise generated when the vehicle turns and improves the riding comfort of passengers; the partial replacement function of the side bearing is realized, and has the characteristics of lower replacement cost and greater convenience.

[0007] In order to solve the above technical problems, the technical solution of the present invention is: a low-floor train side bearing, which includes a friction body, a metal upper plate, a first rubber body, a metal partition, a second rubber body, a metal lower plate and a latch from top to bottom; two friction bodies are arranged on the metal upper plate, and a mounting groove is arranged on the top surface of the metal upper plate corresponding to the friction body, the lower part of the friction body is fixed in the mounting groove by interference fit, the upper part of the friction body is higher than the surface of the metal upper plate, a gap is arranged between the two friction bodies, and a chip removal groove is arranged on the surface of the friction body, and the friction body is made of polytetrafluoroethylene material; the first rubber body and the second rubber body are formed by rubber vulcanization. The principle of the present invention is: cancel the whole-piece design of the friction body, divide the friction body into two pieces, and design a chip groove on the friction body, so that the wear debris generated after friction can be discharged from the chip groove and the gap between the two friction bodies to the contact surface, avoiding the accumulation of materials on the contact surface; improve the material of the friction body, enhance the self-lubricating property and high-temperature resistant bonding property of the friction pair, use polytetrafluoroethylene (PTFE) as the side bearing friction material, and stainless steel metal plate as the friction pair composed of the side bearing wear plate material. Polytetrafluoroethylene has the characteristics of high temperature resistance, corrosion resistance, non-stickiness, self-lubrication, etc., and can meet the requirements of lower friction coefficient when combined with stainless steel. Moreover, the friction pair obtained by the combination has a self-lubricating effect and polytetrafluoroethylene has high temperature resistance. After friction with the side bearing wear plate, no material peeling will occur. Because polytetrafluoroethylene itself is non-sticky, the generated wear debris will not accumulate. Therefore, when the vehicle turns, no high-frequency friction vibration noise will be generated. The split friction body is press-assembled. When the side bearing is manufactured, only the metal upper plate, metal partition plate and metal lower plate are vulcanized together by rubber. The two split friction bodies are installed in the installation groove by cold pressing, which makes it convenient to replace the friction body and reduces the overall replacement cost of the side bearing.

[0008] As an improvement, the metal upper plate is rectangular, the friction bodies are distributed at both ends of the metal upper plate, the mounting groove is circular, and the shape of the friction body is similar to that of the mounting groove.

[0009] As an improvement, the metal upper plate, the metal partition plate and the metal lower plate are all stainless steel metal plates.

[0010] As an improvement, a process hole is provided at the center of the friction body.

[0011] As an improvement, the friction body is provided with two chip removal grooves that intersect and pass through the process hole.

[0012] As an improvement, the width of the chip groove is 4 mm, the depth is 2 mm, and both ends of the chip groove are through.

[0013] As an improvement, the side bearing is fixed to the bolster of the bogie through a side bearing mounting box, and the friction body and the side bearing wear plate mounted on the car body form a friction pair.

[0014] The manufacturing method of the low-floor train side bearing of the present invention comprises the following steps:

[0015] (1) Parts processing: Use polytetrafluoroethylene plate to complete the processing of the friction body, and use stainless steel plate to complete the processing of the metal upper plate, metal lower plate and metal partition;

[0016] (2) Metal plate vulcanization: Use rubber material to vulcanize and bond the finished metal upper plate, metal lower plate and metal partition together to form an integrated structure;

[0017] (3) Pressing the friction body: Use a press machine to press the friction body into the mounting groove of the metal upper plate;

[0018] (4) Marking: After the side bearing is manufactured, the corresponding mark is marked on the visible position of the metal lower plate.

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

[0020] 1. The whole-piece design of the friction body is cancelled, and the friction body is divided into two pieces. A chip groove is designed on the friction body, so that the grinding chips generated after friction can be discharged from the chip groove and the gap between the two friction bodies to the contact surface, avoiding the accumulation of materials on the contact surface; the material of the friction body is improved, and the self-lubrication and high-temperature resistance of the friction pair are improved;

[0021] 2. The friction pair is composed of polytetrafluoroethylene (PTFE) as the side bearing friction material and stainless steel metal plate as the side bearing wear plate material. Polytetrafluoroethylene has the characteristics of high temperature resistance, corrosion resistance, non-stickiness, self-lubrication, etc., and can meet the requirements of lower friction coefficient when combined with stainless steel. In addition, the friction pair obtained by the combination has a self-lubricating effect and polytetrafluoroethylene has high temperature resistance. After friction with the side bearing wear plate, no material will peel off. Since polytetrafluoroethylene itself is non-sticky, the generated wear debris will not accumulate;

[0022] 3. The split friction body is used for press-fit assembly. When the side bearing is manufactured, only the metal upper plate, metal partition plate and metal lower plate are vulcanized together by rubber. The two split friction bodies are installed in the installation groove by cold pressing, which makes it convenient to replace the friction body and reduces the overall replacement cost of the side bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a partial cross-sectional view of the side bearing.

[0024] Figure 2 This is a top view of the side bearing. DETAILED DESCRIPTION

[0025] The present invention will be further described below in conjunction with the accompanying drawings.

[0026] like Figure 1 , 2 As shown, a low-floor train side bearing includes, from top to bottom, a friction body 1, a metal upper plate 2, a first rubber body 3, a metal partition 4, a second rubber body 5, a metal lower plate 6 and a latch 7; the metal upper plate 2, the metal partition 4 and the metal lower plate 6 are all stainless steel metal plates, the first rubber body 3 and the second rubber body 5 are formed by rubber vulcanization, and the metal upper plate 2, the metal partition 4 and the metal lower plate 6 are bonded together. The side bearing is fixed in the side bearing installation box through the latch 7 at the bottom, and finally the side bearing is fixed to the bolster of the bogie through the side bearing installation box, and the friction body 1 and the side bearing wear plate installed on the car body form a friction pair.

[0027] like Figure 1 , 2 As shown, the metal upper plate 2 is rectangular, and two friction bodies 1 are arranged on the metal upper plate 2. The friction bodies 1 are distributed at both ends of the metal upper plate 2, so that the two friction bodies 1 are evenly stressed on the upper metal plate; a mounting groove 13 is arranged on the top surface of the metal upper plate 2 corresponding to the friction body 1, and the mounting groove 13 is circular. The shape of the friction body 1 is similar to that of the mounting groove 13. The lower part of the friction body 1 is fixed in the mounting groove 13 by interference fit, and the upper part of the friction body 1 is higher than the surface of the metal upper plate 2, and a gap is provided between the two friction bodies 1, which can be used for chip removal.

[0028] like Figure 1 , 2 As shown, the side bearing is designed with an M10 process hole 11 at the center of the friction body 1. When the thickness of the side bearing is worn to a limit, the old friction body 1 can be easily pushed out by using a process bolt through the process hole 11, so as to realize the convenient replacement of the friction body 1 and reduce the overall replacement cost of the side bearing. The friction body 1 is provided with two chip grooves 12 that cross and pass through the process hole. The width of the chip groove 12 is 4mm and the depth is 2mm. Both ends of the chip groove 12 are through. The thickness of the friction body 1 affects the life and replacement cycle of the side bearing, and the dynamics affect the safety of vehicle operation. After experimental tracking and verification, the new side bearing was installed on the vehicle and used for 150,000 kilometers. The new side bearing was only worn by 1mm. The mileage of the 70% tram vehicle frame repair is 600,000 kilometers. The wearable thickness of the side bearing should not be less than 4mm. The wearable thickness of the side bearing friction body 1 designed in this embodiment is 5mm, which is feasible. The friction body 1 is made of polytetrafluoroethylene material. By calculating and evaluating the stability of the bogie, the curve passing performance and the wheel running safety under crosswind conditions, the results show that using polytetrafluoroethylene plates as the side bearings of the bogie has little effect on the stability of vehicle operation, but has a certain improvement in safety; for the curve passing performance, the side bearing friction coefficient is smaller, the curve passing performance of the vehicle is better, especially the axle lateral force and the wheel-rail lateral force, both of which are significantly reduced.

[0029] The manufacturing method of the low-floor train side bearing of the present invention comprises the following steps:

[0030] (1) Parts processing: The friction body 1 is processed using a polytetrafluoroethylene plate, and the metal upper plate 2, the metal lower plate 6 and the metal partition plate 4 are processed using a stainless steel plate;

[0031] (2) Metal plate vulcanization: The metal upper plate 2, the metal lower plate 6 and the metal partition plate 4 are vulcanized and bonded together using rubber material to form an integrated structure;

[0032] (3) Pressing the friction body 1: Pressing the friction body 1 into the mounting groove 13 of the metal upper plate 2 by using a press machine;

[0033] (4) Marking: After the side bearing is manufactured, the corresponding mark, including the manufacturing year and month and the drawing number, is marked on the visible position of the metal lower plate 6.

[0034] The principle of the present invention is: cancel the whole block design of the friction body 1, divide the friction body 1 into two pieces, and design a chip groove 12 on the friction body 1, so that the wear debris generated after friction can be discharged from the chip groove 12 and the gap between the two friction bodies 1 to the contact surface, avoiding the accumulation of materials on the contact surface; improve the material of the friction body 1, enhance the self-lubricating property and high temperature resistance of the friction pair, use polytetrafluoroethylene (PTFE) as the side bearing friction material, and stainless steel metal plate as the friction pair composed of the side bearing wear plate material. Polytetrafluoroethylene has the characteristics of high temperature resistance, corrosion resistance, non-stickiness, self-lubrication, etc., and can meet the requirements of lower friction coefficient when combined with stainless steel. Moreover, since the friction pair obtained by the combination has a self-lubricating effect and polytetrafluoroethylene has high temperature resistance, there will be no material peeling after friction with the side bearing wear plate. Since polytetrafluoroethylene itself is non-sticky, the generated wear debris will not accumulate. Therefore, when the vehicle turns, no high-frequency friction vibration noise will be generated. The split friction body 1 is press-assembled and when the side bearing is manufactured, only the metal upper plate 2, the metal partition plate 4 and the metal lower plate 6 are vulcanized together by rubber. The two split friction bodies 1 are installed in the installation groove 13 by cold pressing, so that the friction body 1 can be conveniently replaced and the overall replacement cost of the side bearing is reduced.

[0035] Appendix: Calculate vehicle dynamics after installing the new side bearing structure to evaluate the stability of the bogie, curve passing performance and wheel running safety under crosswind conditions. (Note: 0.3 is the calculation result of the old side bearing, and 0.1 is the calculation result of the new side bearing.)

[0036] Maximum value of wheel-rail lateral force Q on each axle under AW0 condition (unit: kN)

[0037]

[0038] Maximum value of the lateral force H of each axle under AW0 condition (unit: kN)

[0039] R(m) Ax1e1(0.3) Ax1e1(0.1) Ax1e2(0.3) Axle2(0.1) Axle3(0.3) Axle3(0.1) Axle4(0.3) Axle4(0.1) Ax1e5(0.3) Axle5(0.1) Axle6(0.3) Axle6(0.1) 30 27.668 19.784 21.886 11.862 19.77 18.935 10.352 8.595 29.884 20.614 20.151 11.71 50 25.516 18.034 21.145 10.978 17.271 16.476 8.165 7.52 28.471 18.704 18.239 10.216 70 20.574 15.255 16.799 9.963 13.09 13.617 7.079 7.526 21.565 15.354 15.689 10.208 105 16.56 13.421 11.981 8.332 11.609 12.248 5.605 5.795 20.471 14.334 13.633 8.045 200 15.369 12.602 11.205 9.945 9.709 9.279 7.758 8.61 11.228 10.676 10.482 8.353 350 10.925 6.802 11.055 9.547 5.119 4.187 10.354 8.848 8.24 7.58 11.02 11.561 520 7.346 6.109 10.517 10.272 4.11 4.557 10.082 9.533 6.985 5.698 10.369 10.806 600 7.096 5.699 10.868 10.663 4.076 4.127 10.783 10.177 6.345 5.3 11.336 12.329

[0040]

[0041]

[0042]

[0043]

[0044] The results show that using polytetrafluoroethylene plates as the side bearings of the bogies has little effect on the stability of vehicle operation, but has a certain improvement in safety. For curve passing performance, the friction coefficient of the side bearings is smaller, and the curve passing performance of the vehicle is better.

Claims

1. A low-floor train side bearing, characterized in that: From top to bottom, it includes a friction body, a metal upper plate, a first rubber body, a metal partition, a second rubber body, a metal lower plate and a latch; two friction bodies are arranged on the metal upper plate, a mounting groove is arranged on the top surface of the metal upper plate corresponding to the friction body, the lower part of the friction body is fixed in the mounting groove by interference fit, the upper part of the friction body is higher than the surface of the metal upper plate, a gap is arranged between the two friction bodies, the surface of the friction body is arranged with a chip removal groove, and the friction body is made of polytetrafluoroethylene material; the first rubber body and the second rubber body are formed by rubber vulcanization.

2. A low-floor train side bearing according to claim 1, characterized in that: The metal upper plate is rectangular, the friction bodies are distributed at two ends of the metal upper plate, the mounting groove is circular, and the shape of the friction bodies is similar to that of the mounting groove.

3. A low-floor train side bearing according to claim 1, characterized in that: The metal upper plate, metal partition plate and metal lower plate are all stainless steel metal plates.

4. A low-floor train side bearing according to claim 1, characterized in that: A process hole is arranged at the center of the friction body.

5. A low-floor train side bearing according to claim 4, characterized in that: The friction body is provided with two chip removal grooves which intersect and pass through the process hole.

6. The low-floor train side bearing according to claim 1, characterized in that: The width of the chip removal groove is 4 mm, the depth is 2 mm, and both ends of the chip removal groove are through.

7. The low-floor train side bearing according to claim 1, characterized in that: The side bearing is fixed on the bolster of the bogie through a side bearing mounting box, and the friction body and the side bearing wear plate mounted on the car body form a friction pair.

8. A method for manufacturing a low-floor train side bearing as claimed in claim 1, characterized in that: The following steps are involved: (1) Parts processing: Use polytetrafluoroethylene plate to complete the processing of the friction body, and use stainless steel plate to complete the processing of the metal upper plate, metal lower plate and metal partition; (2) Metal plate vulcanization: Use rubber material to vulcanize and bond the finished metal upper plate, metal lower plate and metal partition together to form an integrated structure; (3) Pressing the friction body: Use a press machine to press the friction body into the mounting groove of the metal upper plate; (4) Marking: After the side bearing is manufactured, the corresponding mark is marked on the visible position of the metal lower plate.

Images