A nonlinear anti-sway damper related to an amount of displacement
By designing a variable cross-section oil groove and a damping valve in the shock absorber, the damping force of the shock absorber can be dynamically adjusted under different displacement conditions. This solves the problem of insufficient damping force of traditional shock absorbers when running on straight lines and curves, ensuring the stability and passability of the vehicle.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SOUTHWEST JIAOTONG UNIV
- Filing Date
- 2023-10-26
- Publication Date
- 2026-07-21
AI Technical Summary
Existing shock absorbers cannot adjust the damping force under different displacement conditions, which makes it impossible to meet the vehicle's stability and passability requirements when running on straight lines and curves.
A nonlinear anti-hunting vibration damper is designed. By setting a variable cross-section oil groove and a damping valve in the pressure cylinder, the damping force is adjusted according to the displacement change. The dynamic adjustment of the damping force is achieved by utilizing the change in the area of the variable cross-section oil groove and the cooperation of the damping valve.
When driving on straight lines and curves, the shock absorber can automatically adjust the damping force according to the displacement, ensuring the stability and passability of the vehicle, and solving the problem of damping force contradictions in traditional shock absorbers under different working conditions.
Smart Images
Figure CN117345799B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of vibration damper technology, specifically to a nonlinear anti-hunting vibration damper related to displacement. Background Technology
[0002] Existing vibration dampers maintain a constant damping force at constant speeds as displacement changes. However, in practical engineering and equipment applications, the required damping force often varies under different displacement conditions. For example, in the railway vehicle industry, anti-hunting vibration dampers typically maintain a small amplitude vibration at their installation length when the vehicle is traveling on a straight track, requiring a larger damping force to ensure vehicle stability. Conversely, when the vehicle traverses a curved track, the anti-hunting vibration damper typically maintains a large amplitude vibration under tension or compression, requiring a smaller damping force to ensure smooth passage through the curve. Traditional vibration dampers cannot achieve different damping force magnitudes under different displacements; in most commonly used vibration damper solutions, the damping force remains essentially constant with displacement. It mainly consists of a piston, piston rod, pressure cylinder, oil reservoir, and damping valve. The piston moves back and forth in the pressure cylinder, forcing the viscous medium inside the shock absorber through the piston and the damping valve at the bottom of the pressure cylinder. The molecules of the viscous medium and the viscous medium and the pressure cylinder generate intense friction. The damping valve also has a huge throttling effect on the viscous medium. These internal factors make the shock absorber generate damping force, so as to achieve damping and energy dissipation for vibration reduction. Since the damping effect of the damping valve is not related to the displacement of the shock absorber, the damping force of the traditional shock absorber basically does not change with the displacement. Summary of the Invention
[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a nonlinear anti-hunting vibration damper that is related to the displacement amount. By changing the cross-sectional area of the variable cross-section oil groove on the pressure cylinder under different displacement amounts, the vibration damper can generate different amounts of damping force under different displacement amounts.
[0004] The objective of this invention is achieved through the following technical solution: a nonlinear anti-hunting vibration damper related to displacement, comprising a pressure cylinder and an oil reservoir. The pressure cylinder is fixedly disposed within the oil reservoir, and an oil cavity is formed between the outer wall of the pressure cylinder and the inner wall of the oil reservoir. A piston mechanism is disposed within the pressure cylinder. A variable cross-section oil groove is formed on one inner side wall of the pressure cylinder. The variable cross-section oil groove includes a parallel groove section, a left-inclined groove section, and a right-inclined groove section. The two ends of the parallel groove section are respectively connected to the left-inclined groove section and the right-inclined groove section. The groove depth of the left-inclined groove section gradually decreases along the direction approaching the parallel groove section, and the groove depth of the right-inclined groove section gradually increases along the direction away from the parallel groove section. A damping valve is disposed on the pressure cylinder.
[0005] In some embodiments, an adjusting oil cavity is formed between the outer wall of the pressure cylinder and the inner wall of the variable cross-section oil groove. The left inclined groove section has a left slot opening along its own inclined direction, and the right inclined groove section has a right slot opening along its own inclined direction. Both the left and right slot openings communicate with the adjusting oil cavity. An arc-shaped spring is fixed in both the left and right slot openings. The concave arc surface of the arc-shaped spring is located close to the piston mechanism.
[0006] In some embodiments, a pressure cylinder is provided outside the oil storage tank. One end of the pressure cylinder is connected to the regulating oil chamber through a pressure pipe. A pressure piston is slidably provided on the pressure cylinder, and the pressure piston moves along the axial direction of the pressure cylinder.
[0007] In some embodiments, a lead screw is rotatably installed inside the pressurizing cylinder, and a threaded hole is opened at the end of the pressurizing piston away from the oil storage tank. The lead screw thread is adapted to fit into the threaded hole, and a small motor is installed at the end of the pressurizing cylinder away from the oil storage tank. The output shaft of the small motor is connected to the lead screw.
[0008] In some embodiments, the piston mechanism includes a piston rod and a piston, the piston being slidably disposed within the piston chamber of the pressure cylinder, the piston dividing the piston chamber into a left piston chamber and a right piston chamber, the piston rod being coaxially fixed to one end of the piston, and the end of the piston rod away from the piston extending out of the pressure cylinder.
[0009] In some embodiments, a dust cover is slidably fitted onto the protruding end of the piston rod of the oil storage tank, and the dust cover is fixedly connected to the end of the piston rod away from the piston.
[0010] In some embodiments, rubber joints are fixed to the ends of the dust cover and the oil storage tank.
[0011] In some embodiments, the damping force of the shock absorber is calculated using the following formula: ; in, , These are the cross-sectional area of the oil groove and the effective area of the piston, respectively. The hydraulic radius of the oil tank. The dynamic viscosity of the oil. The length of the hydraulic channel. The damping coefficient is... The piston's speed.
[0012] The beneficial effects of this invention are: 1. Unlike traditional shock absorbers, the pressure cylinder is equipped with damping valves in the tension and compression directions. The displacement-related anti-hunting shock absorber has a variable cross-section oil groove on the inner side of the pressure cylinder, which changes with the displacement. Through the high-precision fit between the piston and the inner surface of the pressure cylinder, the oil can pass through the oil groove with different cross-sectional dimensions under different displacements during tension or compression, thereby generating different magnitudes of damping force.
[0013] 2. When a vehicle is traveling in a straight line, the anti-hunting damper typically vibrates at a small amplitude (within ±5mm) near its installation length. At this point, the oil groove cross-sectional area is at its minimum, and the damping force remains stable with displacement at a constant speed. This relatively large damping force effectively ensures vehicle stability and prevents serpentine instability. When the vehicle is traveling on a curved track, the anti-hunting damper vibrates at a large amplitude near a greater tension or compression position. At this point, the oil groove cross-sectional area increases, the damping force decreases, and the vehicle can smoothly pass through the curve, ensuring its curve clearance. Therefore, displacement-dependent anti-hunting dampers can effectively solve the contradiction in damping force between traditional dampers in straight and curved driving conditions, and can be effectively applied in the rail transit field. Attached Figure Description
[0014] Figure 1 This is a schematic diagram of the internal structure of a nonlinear anti-hunting vibration damper related to displacement according to the present invention; Figure 2 for Figure 1 Sectional view along line AA; Figure 3 for Figure 1 Sectional view along the BB direction; Figure 4 for Figure 1 C-axis sectional view; Figure 5 This is a schematic diagram of the internal structure of the pressure cylinder in a nonlinear anti-hunting vibration damper related to displacement according to the present invention; Figure 6 The diagram shows the relationship between the diameter of the right groove of the variable cross-section oil groove and the displacement. Figure 7 A comparative experimental diagram showing the damping forces of traditional vibration dampers and displacement-dependent vibration dampers; In the diagram, 1-pressure cylinder, 2-oil reservoir, 3-oil chamber, 4-variable cross-section oil groove, 5-parallel groove section, 6-left inclined groove section, 7-right inclined groove section, 8-damping valve, 9-adjusting oil chamber, 10-arc-shaped spring, 11-pressurizing cylinder, 12-pressurizing piston, 13-lead screw, 14-threaded hole, 15-small motor, 16-piston rod, 17-piston, 18-piston left chamber, 19-piston right chamber, 20-dust cover, 21-rubber joint. Detailed Implementation
[0015] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the following description.
[0016] like Figures 1 to 5As shown, a nonlinear anti-hunting vibration damper related to displacement includes a pressure cylinder 1 and an oil reservoir 2. The pressure cylinder 1 is fixedly installed inside the oil reservoir 2. An oil cavity 3 is formed between the outer wall of the pressure cylinder 1 and the inner wall of the oil reservoir 2. A piston mechanism is installed inside the pressure cylinder 1. A variable cross-section oil groove 4 is opened on one inner side wall of the pressure cylinder 1. The variable cross-section oil groove 4 includes a parallel groove section 5, a left-inclined groove section 6, and a right-inclined groove section 7. The two ends of the parallel groove section 5 are respectively connected to the left-inclined groove section 6 and the right-inclined groove section 7. The groove depth of the left-inclined groove section 6 gradually decreases along the direction close to the parallel groove section 5, and the groove depth of the right-inclined groove section 7 gradually increases along the direction away from the parallel groove section 5. A damping valve 8 is installed on the pressure cylinder 1. Two damping valves 8 are provided. One damping valve 8 allows the oil in the oil cavity 3 to enter the pressure cylinder 1, and the other damping valve 8 allows the oil in the pressure cylinder 1 to enter the oil cavity 3. The piston mechanism includes a piston rod. Piston 16 and piston 17 are slidably disposed in the piston chamber of pressure cylinder 1. Piston 17 divides the piston chamber into piston left chamber 18 and piston right chamber 19. Piston rod 16 is coaxially fixed to one end of piston 17. The end of piston rod 16 away from piston 17 passes out of pressure cylinder 1. When piston 17 moves in the stretching direction (i.e., to the left), oil flows from piston left chamber 18 of pressure cylinder 1 into piston right chamber 19 through variable cross-section oil groove 4. Due to the different areas of the left and right sides of piston 17, the amount of oil flowing from piston left chamber 18 into piston right chamber 19 is insufficient. Therefore, a certain amount of oil enters piston right chamber 19 from inside oil storage tank 2 through damping valve 8. When piston 17 moves in the compression direction (i.e., to the right), oil flows from piston right chamber 19 of pressure cylinder 1 into piston left chamber 18 through variable cross-section oil groove 4, and a certain amount of oil enters oil storage tank 2 from piston right chamber 19 through damping valve 8. Because the oil needs to pass quickly through the narrow gap created by the variable cross-section oil groove 4 and the damping valve, the damper will generate a damping force when stretched or compressed. As the piston 17 travels at different strokes, the cross-sectional area of the variable cross-section oil groove 4 changes continuously, and the smoothness of the oil passing through the variable cross-section oil groove 4 varies. Consequently, the damping force of the damper at the same speed can change with the displacement. Preferably, the parallel groove section 5 is set within ±5mm of the damper installation length. Since the damping force requirements of the anti-hunting damper for railway vehicles under straight and curved conditions are different, the variable cross-section oil groove 4 is specially designed with the limit position of the damper piston 17 in the tensile direction as the zero displacement point. As the damper piston 17 moves in the compression direction, the diameter of the variable cross-section oil groove 4 first shows a linear decreasing trend; when the damper piston 17 moves to within ±5mm of the damper installation length, the diameter of the variable cross-section oil groove 4 decreases to the limit value, and the diameter of the variable cross-section oil groove 4 remains unchanged within this range; when the damper piston moves further in the compression direction, the diameter of the variable cross-section oil groove 4 shows a linear increasing trend. The formula for calculating the damping force of a shock absorber can be approximated as follows: in, , These are the cross-sectional area of the oil groove and the effective area of piston 17, respectively. The hydraulic radius of the oil tank. The dynamic viscosity of the oil. The length of the hydraulic channel. The damping coefficient is... The piston's speed.
[0017] As can be seen from the above formula, the damping force of the shock absorber decreases rapidly with the increase of the cross-sectional diameter of the oil groove. Therefore, after the oil groove of the displacement-dependent nonlinear anti-hunting damper is set as described above, when the vehicle is running in a straight line, the anti-hunting shock absorber usually vibrates at a small amplitude (within ±5mm) near the installation length. At this time, the cross-sectional area of the oil groove is the smallest, and the damping force of the shock absorber remains stable with displacement at a constant speed. At this time, the damping force is relatively large, which can effectively ensure the stability of vehicle operation and prevent serpentine instability. When the vehicle is running on a curved track, the anti-hunting shock absorber vibrates at a large amplitude near a larger tension or compression position. At this time, the cross-sectional area of the oil groove becomes larger, the damping force is smaller, and the vehicle can pass through the curve smoothly, ensuring the vehicle's curve passability.
[0018] In some embodiments, such as Figure 1 and Figure 5As shown, an adjusting oil chamber 9 is formed between the outer wall of the pressure cylinder 1 and the inner wall of the variable cross-section oil tank 4. A left inclined groove section 6 has a left opening along its own inclined direction, and a right inclined groove section 7 has a right opening along its own inclined direction. Both the left and right openings communicate with the adjusting oil chamber 9. An arc-shaped spring piece 10 is fixed inside both the left and right openings. The concave arc surface of the arc-shaped spring piece 10 is positioned close to the piston mechanism. A pressure cylinder 11 is installed outside the oil storage tank 2. One end of the pressure cylinder 11 is connected to the adjusting oil chamber 9 via a pressure pipe. A pressure piston 12 is slidably installed on the pressure cylinder 11. The pressure piston 12 moves along the axial direction of the pressure cylinder 11. A lead screw 13 is rotatably installed inside the pressure cylinder 11. A threaded hole 14 is opened at the end of the pressure piston 12 away from the oil storage tank 2. The thread of the lead screw 13 is fitted into the threaded hole 14. A... A small motor 15 is connected to a lead screw 13 via its output shaft. The cross-sectional areas of the left inclined groove section 6 and the right inclined groove section 7 can be adjusted by changing the deformation of the arc-shaped spring 10, thereby changing the initial value of the damping force. Specifically, the small motor 15 drives the lead screw 13 to rotate, causing the pressure piston 12 to move axially along the pressure cylinder 11, thereby pressurizing the oil in the regulating oil chamber 9. Under the action of pressure, the deformation of the arc-shaped spring 10 is changed, thereby achieving the effect of the cover plate value. The threaded connection between the pressure piston 12 and the lead screw 13 locks the position of the pressure piston 12, ensuring the stability of the deformation of the arc-shaped spring 10. Thus, by moving the pressure piston 12 back and forth, the oil pressure in the regulating oil chamber 9 is controlled, thereby changing the deformation of the arc-shaped spring 10, and thus achieving the effect of adjusting the value.
[0019] In some embodiments, such as Figure 1 As shown, a dust cover 20 is slidably fitted onto the protruding end of the piston rod 16 in the oil storage tank 2. The end of the piston rod 16 away from the piston 17 is fixedly connected to the dust cover 20. The dust cover 20 is used to prevent dust, sand, and foreign objects from damaging or impacting the piston rod 16. Rubber nodes 21 are fixed to the ends of the dust cover 20 and the ends of the oil storage tank 2 to provide a buffering effect.
[0020] like Figure 6 and Figure 7As shown, when a vehicle is traveling in a straight line, the anti-hunting damper typically vibrates at a small amplitude (within ±5mm) near its installation length. At this point, the oil groove cross-sectional area is at its minimum, and the damping force remains stable with displacement at a constant speed. This relatively large damping force effectively ensures vehicle stability and prevents serpentine instability. When the vehicle is traveling on a curved track, the anti-hunting damper vibrates at a large amplitude near a larger tension or compression position. At this point, the oil groove cross-sectional area increases, the damping force decreases, and the vehicle can smoothly pass through the curve, ensuring its curve clearance. Therefore, displacement-dependent anti-hunting dampers can effectively solve the contradiction in damping force between traditional dampers in straight and curved driving conditions, and can be effectively applied in the rail transit field.
[0021] In the description of this invention, it should be understood that the terms "coaxial," "bottom," "one end," "top," "middle," "other end," "upper," "side," "top," "inner," "front," "center," and "both ends," 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 this invention and simplifying the description, 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 this invention. Furthermore, those skilled in the art will understand that the beneficial effects to be achieved by this invention are merely to achieve better beneficial effects compared with the current embodiments in the prior art under specific conditions, rather than to directly achieve the best use effect in the industry.
[0022] The above description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the concept described herein through the above teachings or related technologies or knowledge. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.
Claims
1. A nonlinear anti-hunting vibration damper related to displacement, characterized in that, The device includes a pressure cylinder (1) and an oil storage tank (2). The pressure cylinder (1) is fixedly installed inside the oil storage tank (2). An oil cavity (3) is formed between the outer wall of the pressure cylinder (1) and the inner wall of the oil storage tank (2). A piston mechanism is installed inside the pressure cylinder (1). A variable cross-section oil groove (4) is opened on one inner side wall of the pressure cylinder (1). The variable cross-section oil groove (4) includes a parallel groove section (5), a left inclined groove section (6), and a right inclined groove section (7). The two ends of the parallel groove section (5) are respectively connected to the left inclined groove section (6) and the right inclined groove section (7). The groove depth of the left inclined groove section (6) gradually decreases along the direction close to the parallel groove section (5). The right inclined groove (7) has a groove depth that gradually increases in the direction away from the parallel groove (5). The pressure cylinder (1) is equipped with a damping valve (8). An adjustment oil chamber (9) is formed between the outer wall of the pressure cylinder (1) and the inner wall of the variable cross-section oil groove (4). The left inclined groove (6) has a left groove opening along its own inclined direction. The right inclined groove (7) has a right groove opening along its own inclined direction. The left groove opening and the right groove opening are both connected to the adjustment oil chamber (9). An arc-shaped spring piece (10) is fixed in the left groove opening and the right groove opening. The concave arc surface of the arc-shaped spring piece (10) is located close to the piston mechanism.
2. The nonlinear anti-hunting vibration damper related to displacement as described in claim 1, characterized in that, A pressure cylinder (11) is provided on the outside of the oil storage tank (2). One end of the pressure cylinder (11) is connected to the regulating oil chamber (9) through a pressure pipe. A pressure piston (12) is slidably provided on the pressure cylinder (11). The pressure piston (12) moves along the axial direction of the pressure cylinder (11).
3. A nonlinear anti-hunting vibration damper related to displacement as described in claim 2, characterized in that, A lead screw (13) is rotatably installed inside the pressurizing cylinder (11). A threaded hole (14) is opened at one end of the pressurizing piston (12) away from the oil storage tank (2). The lead screw (13) is threaded into the threaded hole (14). A small motor (15) is installed at one end of the pressurizing cylinder (11) away from the oil storage tank (2). The output shaft of the small motor (15) is connected to the lead screw (13).
4. A nonlinear anti-hunting vibration damper related to displacement as described in claim 1, characterized in that, The piston mechanism includes a piston rod (16) and a piston (17). The piston (17) is slidably disposed in the piston chamber of the pressure cylinder (1). The piston (17) divides the piston chamber into a left piston chamber (18) and a right piston chamber (19). The piston rod (16) is coaxially fixed to one end of the piston (17). The end of the piston rod (16) away from the piston (17) passes through the pressure cylinder (1).
5. A nonlinear anti-hunting vibration damper related to displacement as described in claim 4, characterized in that, The oil storage tank (2) is slidably fitted with a dust cover (20) at the protruding end of the piston rod (16), and the end of the piston rod (16) away from the piston (17) is fixedly connected to the dust cover (20).
6. A nonlinear anti-hunting vibration damper related to displacement as described in claim 5, characterized in that, Rubber nodes (21) are fixed to the ends of the dust cover (20) and the oil storage tank (2).
7. A nonlinear anti-hunting vibration damper related to displacement as described in claim 4, characterized in that, The formula for calculating the damping force of a shock absorber is: ； in, These are the cross-sectional area of the oil tank and the effective area of the piston (17), respectively. The hydraulic radius of the oil tank. The dynamic viscosity of the oil. The length of the hydraulic channel. The damping coefficient is... The piston's speed.