Friction damper

Abstract

The friction damper comprises an outer cylinder, a split piston assembly sleeved in the outer cylinder, a mounting block arranged above the outer cylinder, a connecting plate connected with the split piston assembly and the mounting block and arranged axially along the outer cylinder, and an axial spring sleeved outside the connecting plate and compressed between the mounting block and the split piston assembly, characterized in that the split piston assembly comprises two piston half-rings, a radial spring compressed between the two piston half-rings, and detachable friction plates arranged on the piston half-rings and in friction fit with the inner wall of the outer cylinder, the cross section of the piston half-ring is semicircular, the piston half-ring is provided with two friction plates, and the two friction plates are symmetrically arranged on the two sides of the radial spring. The utility model ensures that the two friction plates are uniformly stressed and rubbed during the damping process, the friction plates can be uniformly attached to the inner wall of the outer cylinder, the reliability of the friction vibration absorption is improved, the friction plates are detachably arranged on the piston half-rings, the piston half-rings and the friction plates are not integrally replaced, the maintenance cost is reduced, and the practicality is improved.

Description

Technical Field

[0001] This utility model relates to a friction damper, belonging to the technical field of dampers for railway locomotives and rolling stock. Background Technology

[0002] The wheelsets of locomotives and rolling stock have a steel-to-steel contact with the rail surface. Irregularities on the wheel surface and unevenness in the rail are directly transmitted to the suspension components, causing high-frequency and low-frequency vibrations in various parts of the locomotive and rolling stock. Therefore, the suspension components need to be equipped with shock absorbers to dampen vibrations. Friction shock absorbers utilize friction to dissipate vibration energy and dampen vibrations. They mainly consist of a metal cylinder, a two-lobed piston, and friction plates fixed on the piston. The friction plates are pressed against the inner wall of the metal cylinder by springs between the two piston lobes. Friction is generated between the non-metallic friction plates and the metal cylinder, converting the mechanical energy of the vibration into frictional heat energy that is dissipated outwards. To ensure that the friction plates are effectively clamped between the piston and the metal cylinder, the friction plates are generally vulcanized onto the piston. Uneven force on the friction plates or uneven contact between the friction plates and the cylinder wall during the friction process will cause uneven friction, affecting the damping effect. Moreover, as the friction plates become thinner, the entire piston assembly needs to be replaced during use, resulting in piston waste and increased maintenance costs. Utility Model Content

[0003] The friction damper provided by this utility model ensures that the two friction plates are subjected to uniform force and friction during the damping process, and that the friction plates can be evenly attached to the inner wall of the outer cylinder, thereby improving the reliability of friction vibration absorption. The friction plates are detachably mounted on the piston half-ring, which facilitates the individual replacement of the friction plates during maintenance and inspection, avoiding the need to replace the piston half-ring and friction plates together, reducing maintenance costs and improving practicality.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows: A friction damper includes an outer cylinder, a split piston assembly sleeved inside the outer cylinder, a mounting block positioned directly above the outer cylinder, a connecting plate connecting the split piston assembly and the mounting block and arranged axially along the outer cylinder, and an axial spring sleeved outside the connecting plate and compressed between the mounting block and the split piston assembly. The split piston assembly comprises two piston half-rings, a radial spring compressed between the two piston half-rings, and detachable friction plates mounted on the piston half-rings and in frictional engagement with the inner wall of the outer cylinder. The piston half-rings have a semi-circular cross-section and two friction plates symmetrically arranged on both sides of the radial spring.

[0005] Preferably, the outer wall of the piston semi-ring has a mounting plane that contacts the friction plate. The inner surface of the friction plate is a plane that fits with the mounting plane, and the outer surface is an arc surface with a diameter equal to the inner diameter of the outer cylinder. The friction plate has a radial countersunk through hole at the mounting plane position. The piston semi-ring has a riveting hole corresponding to the countersunk through hole. The rivet passes through the riveting hole and extends into the countersunk through hole to fix the friction plate to the piston semi-ring.

[0006] Preferably, a circular groove corresponding to the radial spring is formed on the inner wall of the piston half-ring, and the end of the radial spring extends into the circular groove.

[0007] Preferably, an inner connecting block is welded to the inner wall of the piston half-ring. The inner connecting block is located above the radial spring. The inner connecting blocks of the two piston half-rings are spaced apart from each other. The lower end of the axial spring abuts against the inner connecting block. The lower end of the connecting plate is connected to the inner connecting block.

[0008] Preferably, the lower end of the connecting plate extends between the two inner connecting blocks and is separated from and does not contact the inner connecting blocks. An inclined hole is opened on the inner connecting block, and the inclined hole extends to the piston half ring. A circular hole corresponding to the inclined hole is opened on the connecting plate. An upwardly protruding arc-shaped connecting pin passes through the circular hole and its end is spaced and inserted into the inclined hole. The upper end of the connecting plate is connected to the mounting block by a pin.

[0009] The beneficial effects of this utility model are: This utility model discloses a friction damper connected between the axle box and the bogie or between the bogie and the car body. The connecting plate reciprocates up and down to transmit vibration force to the split piston assembly. The axial spring and the split piston assembly jointly participate in vibration damping. Two friction plates are mounted on the piston half-ring, and the two friction plates are symmetrically arranged on both sides of the radial spring. This allows the two friction plates to evenly bear the pressure transmitted by the piston half-ring and press against the inner wall of the outer cylinder, ensuring that the two friction plates are evenly subjected to friction during vibration damping, thereby improving the reliability of friction vibration absorption. The friction plates are detachably mounted on the piston half-ring, which facilitates the individual replacement of the friction plates during maintenance, avoiding the need to replace the piston half-ring and friction plates together, reducing maintenance costs and improving practicality.

[0010] An mounting plane is set on the piston half-ring, the inner surface of the friction plate fits into the mounting plane, and the outer surface is an arc surface with a diameter equal to the inner diameter of the outer cylinder, ensuring that the friction plate can fit evenly against the inner wall of the outer cylinder and improve the vibration reduction effect. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the friction damper of this utility model.

[0012] Figure 2 for Figure 1 Sectional view along the BB direction.

[0013] Figure 3 This is a schematic diagram of a split piston assembly with the radial spring in a free-relaxed state. Detailed Implementation

[0014] The following is combined Figures 1-3 The embodiments of this utility model will be described in detail below.

[0015] A friction damper includes an outer cylinder 1, a split piston assembly 2 sleeved inside the outer cylinder 1, a mounting block 3 positioned directly above the outer cylinder 1, a connecting plate 4 connecting the split piston assembly 2 and the mounting block 3 and arranged axially along the outer cylinder 1, and an axial spring 5 sleeved outside the connecting plate 4 and compressed between the mounting block 3 and the split piston assembly 2. The split piston assembly 2 comprises two piston half-rings 6, a radial spring 7 compressed between the two piston half-rings 6, and detachable friction plates 8 mounted on the piston half-rings 6 and in frictional engagement with the inner wall of the outer cylinder 1. The piston half-rings 6 have a semi-circular cross-section, and the piston half-rings 6 have two friction plates 8, which are symmetrically arranged on both sides of the radial spring 7.

[0016] The friction damper described above is connected between the axle box and the bogie or between the bogie and the car body. The connecting plate 4 reciprocates up and down to transmit vibration force to the split piston assembly 2. The axial spring 5 and the split piston assembly 2 jointly participate in vibration damping. Two friction plates 8 are mounted on the piston half ring 6, and the two friction plates 8 are symmetrically arranged on both sides of the radial spring 7, so that the two friction plates 8 are evenly subjected to the pressure transmitted by the piston half ring 6 and pressed against the inner wall of the outer cylinder 1. This ensures that the two friction plates 8 are evenly subjected to friction during vibration damping, thereby improving the reliability of friction vibration absorption. The friction plates 8 are detachably mounted on the piston half ring 6, which facilitates the individual replacement of the friction plates during maintenance and inspection, avoiding the replacement of the piston half ring and friction plates as a whole, reducing maintenance costs and improving practicality.

[0017] The piston half-ring 6 has an outer wall with a mounting plane 61 that contacts the friction plate 8. The inner surface of the friction plate 8 is a plane that fits with the mounting plane 61, and the outer surface is an arc surface with a diameter equal to the inner diameter of the outer cylinder 1. The friction plate 8 has a radial countersunk through hole 81 at the mounting plane position. The piston half-ring 6 has a riveting hole 62 corresponding to the countersunk through hole 81. The rivet 9 passes through the riveting hole 62 and extends into the countersunk through hole 81 to fix the friction plate 8 on the piston half-ring 6. As shown in the attached diagram, the inner surface of the friction plate 8 is in contact with the mounting plane 61, and the outer surface is an arc surface with a diameter equal to the inner diameter of the outer cylinder 1, ensuring that the friction plate 8 can fit evenly against the inner wall of the outer cylinder and improve the vibration damping effect. The inner end of the rivet is pressed against the end face of the rivet hole 62, and the outer end is pressed against the countersunk surface of the countersunk through hole 81, thus fastening the friction plate to the piston half ring 6. When the friction plate 8 needs to be replaced, the rivet is removed first, and then a new rivet is used to fix the new friction plate to the piston half ring 6. The positioning structure of the friction plate 8 on the piston half ring 6 is simple and easy to replace. The friction plate 8 can be made of a high wear-resistant polymer material to extend its service life.

[0018] The inner wall of the piston half-ring 6 has a circular groove 63 corresponding to the radial spring, and the end of the radial spring 7 extends into the circular groove 63. The circular groove 63 positions the radial spring 7, preventing it from shifting on the piston half-ring 6 during vibration damping, and further improving the uniformity of force on the two friction plates 8 on the piston half-ring 6.

[0019] In this design, an inner connecting block 10 is welded to the inner wall of the piston half-ring 6. The inner connecting block 10 is located above the radial spring 7. The inner connecting blocks 10 of the two piston half-rings 6 are spaced apart from each other. The lower end of the axial spring 5 abuts against the inner connecting block 10, and the lower end of the connecting plate 4 is connected to the inner connecting block 10. When the friction damper is installed on the primary suspension of the locomotive, the mounting block 3 is connected to the bogie, and the lower end of the outer cylinder 1 is connected to the axle box. When it is installed on the secondary suspension of the locomotive, the mounting block 3 is connected to the car body, and the lower end of the outer cylinder 1 is connected to the bogie. The setting of the inner connecting block 10 compresses the axial spring 5 between the mounting block 3 and the inner connecting block 10, and together with the split piston assembly 2, it participates in vibration damping, improving the installation convenience of the axial spring 5.

[0020] The lower end of the connecting plate 4 extends between the two inner connecting blocks 10 and is separated from and does not contact the inner connecting blocks 10. An inclined hole 11 is formed on the inner connecting block 10, extending to the piston half-ring 6. A circular hole 41 corresponding to the inclined hole is formed on the connecting plate 4. An upwardly protruding arc-shaped connecting pin 12 passes through the circular hole 41 and extends into the inclined hole 11 with its end spaced apart. The upper end of the connecting plate 4 is connected to the mounting block 3 via a pin 13. The arc-shaped connecting pin, passing through the circular hole 41 and extending into the inclined hole 11, connects the lower end of the connecting plate 4 to the inner connecting block 10. During use, as the friction plate 8 thins, the arc-shaped connecting pin 12 will also deform downwards to ensure that even when the gap between the two inner connecting blocks 10 increases, the arc-shaped connecting pin 12 can still maintain its fit with the inclined hole 11, preventing the gap between the arc-shaped connecting pin 12 and the inclined hole 11 from increasing due to the thinning of the friction plate 8, thus ensuring the reliable connection between the connecting plate 4 and the piston half-ring 6.

[0021] The technical solutions of the embodiments of this utility model have been fully described above with reference to the accompanying drawings. It should be noted that the described embodiments are only a part of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

Claims

1. A friction damper, comprising an outer cylinder, a split piston assembly sleeved within the outer cylinder, a mounting block positioned directly above the outer cylinder, a connecting plate connecting the split piston assembly and the mounting block and axially arranged along the outer cylinder, and an axial spring sleeved outside the connecting plate and compressed between the mounting block and the split piston assembly, characterized in that: The split piston assembly includes two piston half-rings, a radial spring compressed between the two piston half-rings, and detachable friction plates mounted on the piston half-rings and in frictional engagement with the inner wall of the outer cylinder. The piston half-rings have a semi-circular cross-section and two friction plates on each piston half-ring, which are symmetrically arranged on both sides of the radial spring.

2. The friction damper according to claim 1, characterized in that: The outer wall of the piston half-ring has a mounting plane that contacts the friction plate. The inner surface of the friction plate is a plane that fits with the mounting plane, and the outer surface is an arc surface with a diameter equal to the inner diameter of the outer cylinder. The friction plate has a radial countersunk through hole at the mounting plane position. The piston half-ring has a riveting hole corresponding to the countersunk through hole. The rivet passes through the riveting hole and extends into the countersunk through hole to fix the friction plate on the piston half-ring.

3. The friction damper according to claim 2, characterized in that: A circular groove corresponding to the radial spring is formed on the inner wall of the piston half-ring, and the end of the radial spring extends into the circular groove.

4. The friction damper according to claim 1, characterized in that: An inner connecting block is welded to the inner wall of the piston half-ring. The inner connecting block is located above the radial spring. The inner connecting blocks of the two piston half-rings are spaced apart from each other. The lower end of the axial spring abuts against the inner connecting block. The lower end of the connecting plate is connected to the inner connecting block.

5. The friction damper according to claim 4, characterized in that: The lower end of the connecting plate extends between the two inner connecting blocks and is separated from and does not contact the inner connecting blocks. An inclined hole is opened on the inner connecting block, and the inclined hole extends to the piston half ring. A circular hole corresponding to the inclined hole is opened on the connecting plate. An upwardly protruding arc-shaped connecting pin passes through the circular hole and its end is spaced and inserted into the inclined hole. The upper end of the connecting plate is connected to the mounting block through a pin.

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