An irregular rubber spring and its stiffness adjustment method

Abstract

An abnormal-shaped rubber spring and its stiffness adjustment method. The rubber spring includes a core shaft in the innermost layer, a jacket in the outermost layer, and a rubber body vulcanized between the core shaft and the jacket. The core shaft, the rubber body, and the jacket are all waist-shaped cylinders with one end larger and the other end smaller. The lateral width of the rubber spring is 140 - 220 mm. The vertical stiffness of the rubber spring can be adjusted by adjusting the proportion of each section of rubber in the vertical direction of the rubber body, and the vertical stiffness of the rubber spring can also be adjusted by adjusting the angle between each section of rubber in the vertical direction of the rubber body. The rubber spring of the present invention adopts a waist-shaped cylinder structure, which greatly reduces the lateral width and fully meets the narrow installation space environment in the inner support type bogie structure. At the same time, it can also be used in the outer support type bogie and other vibration damping places. Its vertical stiffness can be adjusted within a wide range, broadening the scope of use and being applicable to various different occasions.

Description

Technical Field

[0001] The present invention relates to a rubber spring and a method for adjusting its stiffness, and more particularly to a special-shaped rubber spring suitable for an inner-supported bogie and a method for adjusting its stiffness, belonging to the technical field of vibration reduction. Background Art

[0002] In the new generation of high-speed trains, due to higher speeds, higher adaptability requirements are put forward for vehicle vibration, noise and energy consumption. Therefore, it is required that the vehicle be lighter in weight and better in vibration reduction effect. For the bogie frame connecting the wheelset and the car body, it is required to have a compact layout and stronger curve passing ability. Compared with the traditional externally-mounted axle box bogie, the use of an internally-mounted axle box bogie can significantly reduce the weight of the entire bogie frame. Currently, the rubber springs at the bogies of rail vehicles are basically annular conical springs to transmit vertical loads, lateral loads and torques, absorb vertical and horizontal vibrations, provide horizontal restoring forces, etc. For example, the invention patent application with the application number 201811318203.X and the name of "Conical Spring and Its Variable Stiffness and Installation Adjustment Method", the invention patent application with the application number 201510115752.7 and the name of "Upper End Face of Conical Spring Rubber Body and Method and Product for Preventing Wrinkles and Cracks", and the invention patent application with the application number 201910624501.X and the name of "A Method and Structure for Adjusting the Stiffness of a Conical Spring" can all be installed between the axle box and the frame to play a role in support, shock absorption and noise reduction. However, the above structures all require a large installation space and are not very suitable for the inner-supported bogie frame with a very narrow lateral installation space. Summary of the Invention

[0003] Aiming at the problem that the current conical spring at the axle box requires a large installation space and cannot be applied to the compact inner-supported bogie structure, the present invention proposes a special-shaped rubber spring and a method for adjusting its stiffness, which greatly reduces the width of its narrow side. When installed, the narrow side direction is placed in the vehicle lateral direction, which can greatly release the lateral space.

[0004] The technical means adopted by the present invention to solve the above problems is: a special-shaped rubber spring, including a core shaft at the innermost layer, an outer sleeve at the outermost layer, and a rubber body vulcanized between the core shaft and the outer sleeve. The core shaft, the rubber body and the outer sleeve are all waist-shaped cylinders with one end large and one end small. The lateral width of the rubber spring is 140 - 220 mm, which greatly reduces the lateral installation space.

[0005] Further, the lateral width at the small end of the rubber spring is 40 - 120 mm, and the lateral width at the large end is 160 - 180 mm.

[0006] Further, the core shaft is a hollow structure inside, which can reduce the weight of the rubber spring and meet the weight reduction requirements.

[0007] Further, the connecting line of the contact surfaces between the rubber body and the mandrel and the outer sleeve in the longitudinal sectional view is composed of more than two straight line segments, realizing the non-linear change of the rubber spring stiffness.

[0008] Further, when the connecting line is composed of two straight line segments, the included angle between the two straight line segments is 150 - 180 o . Avoid occupying too much lateral space when the included angle is too small.

[0009] Further, when the connecting line is composed of more than three straight line segments, the included angle between two adjacent straight line segments near the small end is greater than the included angle between two adjacent straight line segments near the large end. Realize the multiple non-linear change of the rubber spring stiffness.

[0010] Further, a spacer sleeve is arranged vertically inside the rubber body, and both sides of the spacer sleeve are vulcanized and connected to the rubber. Adjust the stiffness by adding or subtracting the spacer sleeve.

[0011] Further, the spacer sleeve is also a waist-shaped cylinder with one end large and one end small, and the number of spacer sleeves is set to more than one according to the stiffness requirement.

[0012] Further, a retaining ring protruding from the outer circumference of the bottom of the mandrel is provided. Variable stiffness can be realized again at the retaining ring, and it plays a role of stopping.

[0013] Further, the mandrel, the spacer sleeve and the outer sleeve are all higher than the rubber surface at their joints at both ends.

[0014] The beneficial effects of the present invention are as follows:

[0015] 1. The rubber spring of the present invention adopts a waist-shaped cylinder structure, greatly reducing the lateral width, fully meeting the narrow installation space environment in the inner support type bogie structure. Of course, it can also be used in the outer support type bogie and other vibration damping places, broadening the scope of use and being applicable to various different occasions.

[0016] 2. The rubber spring of the present invention is designed to have a structure with a large end and a small end, realizing variable stiffness at the connection between the large end and the small end, meeting the variable stiffness requirements; moreover, it can also be designed into a structure with multiple joints at different angles to realize multiple variable stiffness. Thus, the non-linear change of the vertical stiffness is realized, and the non-linear inflection point can be adjusted within a large range.

[0017] 3. The present invention can adjust the stiffness not only by changing the subtle shapes of the mandrel and the outer sleeve, but also by increasing or decreasing the spacer sleeve, improving the adjustment range of the stiffness, making the stiffness adjustable within a large range, and being able to meet different stiffness requirements.

[0018] 4. The present invention adopts arc smooth connection at both ends in the longitudinal direction, which is beneficial to improving the longitudinal load-bearing uniformity, reducing the rubber strain and increasing the service life.

[0019] 5. The present invention has low creep characteristics, and the creep can be controlled within ≤5 mm.

[0020] 6. The bonding area between the rubber and the metal in the present invention is large, which is beneficial to improving its reliability as a rubber spring.

[0021] 7. The rubber spring of the present invention is simple and flexible to install, and can adopt a variety of assembly structures. Especially at the large end of the bottom, the internal cavity of the mandrel can be designed as a positioning hole with very high precision, and a positioning pin can be set on the axle box for accurate positioning and installation. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is an overall schematic diagram of the rubber spring in Embodiment 1 from a top view angle;

[0023] Figure 2 It is an overall schematic diagram of the rubber spring in Embodiment 1 from a bottom view angle;

[0024] Figure 3 It is Figure 1 a schematic cross-sectional view taken along the line A-A;

[0025] Figure 4 It is Figure 3 a schematic diagram of the rubber body in

[0026] Figure 5 It is an overall schematic diagram of the mandrel in Embodiment 1;

[0027] Figure 6 It is Figure 5 a side view schematic diagram;

[0028] Figure 7 It is an overall schematic diagram of the outer sleeve in Embodiment 1;

[0029] Figure 8 It is Figure 7 a side view schematic diagram;

[0030] Figure 9 It is an overall schematic diagram of the spacer sleeve in Embodiment 1;

[0031] Figure 10 It is Figure 9 a side view schematic diagram;

[0032] Figure 11 It is a schematic cross-sectional view of the rubber spring structure in Embodiment 2;

[0033] Figure 12 It is Figure 11 a schematic diagram of the mandrel structure in

[0034] In the figure: 1. Mandrel, 2. Rubber body, 3. Outer sleeve, 4. Spacer sleeve, 5. Socket, 6. Retaining ring. Detailed implementation mode

[0035] The present invention will be further described below with reference to the accompanying drawings. Among them, the accompanying drawings are only for illustrative purposes, showing only schematic diagrams, not physical diagrams, and should not be construed as a limitation of this patent; in order to better illustrate the embodiments of the present invention, some components in the accompanying drawings will be omitted, enlarged or reduced, which does not represent the size of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the accompanying drawings may be omitted.

[0036] Embodiment 1

[0037] This embodiment is a preferred embodiment. A special-shaped rubber spring, as shown in Figure 1 and Figure 2 , from the inside to the outside, includes a mandrel 1, a rubber body 2 and an outer sleeve 3, and a spacer sleeve 4 is also vulcanized in the rubber body 2 to form a structure in which metal-rubber-metal-rubber-metal is vulcanized into one body. As shown in Figures 3 - 10 , the mandrel 1, the rubber body 2, the spacer sleeve 4 and the outer sleeve 3 are all waist-shaped cylinders with large ends and small ends, and the rubber spring as a whole is also a waist-shaped cylinder with a large end and a small end. Among them, the mandrel 1 has a cavity structure inside, which reduces the weight of the mandrel 1 while ensuring strength, and the cavity is also a waist-shaped cylinder with a large end and a small end. During assembly, the small end is on the upper side and is connected to the bogie through the outer sleeve 3, and the large end is on the lower side and is connected to the axle box through the mandrel 1. As shown in Figure 2 , the direction of the line connecting the large end and the small end of the special-shaped spring is called the vertical direction, the direction with a larger width in the waist-shaped cylinder is called the longitudinal direction, and the direction with a smaller width in the waist-shaped cylinder is called the transverse direction.

[0038] As shown in Figure 4 , in the longitudinal cross-section of the rubber body 2, its edge line is two broken lines a and b (where each broken line a is parallel to each other), and an angle A is formed between the broken line a and the broken line b. Correspondingly, angles will also be formed on the vertical planes of the mandrel 1, the spacer sleeve 4 and the outer sleeve 3. In this embodiment, the thickness of the rubber body 1 is the same everywhere, and the broken lines a on both sides of the mandrel 1 are parallel to each other. Therefore, when carrying in the vertical direction, the load borne by the bogie is transmitted to the rubber body 2 in the vertical direction through the outer sleeve 3, and the part at the small end of the mandrel 1 does not provide vertical support for the rubber body 2. When the rubber is squeezed and deformed to a certain extent, the large end of the mandrel 1 provides vertical support for the rubber body 2, realizing variable stiffness. By adjusting the length ratio between the broken line a and the broken line b, the conditions required for variable stiffness to occur can be adjusted. For example, when shortening the length of the broken line a and increasing the length of the broken line b, the amount by which the rubber can be compressed before variable stiffness occurs will be reduced, so as to realize variable stiffness earlier; on the contrary, if the length of the broken line a is increased and the length of the broken line b is shortened, the amount by which the rubber can be compressed before variable stiffness occurs can be increased, thereby delaying the realization of variable stiffness.

[0039] In addition, as shown in Figure 4As shown, the included angle A is set to be 150 - 180 o , the larger the angle, the smaller the vertical stiffness that the mandrel 1 can provide; the smaller the angle, the larger the vertical stiffness that the mandrel 1 can provide. However, if it is set too small, the width of the large end of the rubber spring in the transverse direction will increase, occupying the transverse space and reducing the space utilization rate. Therefore, by adjusting the size of the angle A and coordinating with the adjustment of the length ratio between the broken line a and the broken line b, a large range of changes in the vertical stiffness (0.5 kN / mm - 10 kN / mm) can be achieved, while matching a large longitudinal stiffness or a large transverse stiffness (5 kN / mm - 100 kN / mm). For example, when increasing the length of the broken line a and simultaneously increasing the size of the angle A, so that the rubber is under more shear loading conditions, the vertical stiffness of the rubber spring can be significantly reduced; conversely, if the length of the broken line a is reduced and the size of the angle B is reduced simultaneously, so that the rubber receives more vertical support provided by the large end of the mandrel 1, the vertical stiffness of the rubber spring can be significantly increased. For trains, different vehicles with different functions have different load requirements, so there will be requirements for the vertical stiffness. Therefore, a structure that can be flexibly adjusted in a large range is very necessary. Moreover, by increasing or decreasing the number of partitions and increasing or decreasing the thickness of the rubber body 2, the range of stiffness in all directions can also be adjusted. Of course, the mandrel 1, the rubber body 2, the spacer sleeve 4, and the outer sleeve 3 can adopt a structure with the same thickness everywhere, or a structure with unequal thicknesses everywhere. When the thicknesses are different everywhere, the size of the angle A at each place is adjusted according to needs. Whether it is a structure with equal thicknesses everywhere or a structure with unequal thicknesses everywhere, the vertex of the included angle A formed between the broken line a and the broken line b of the mandrel 1, the rubber body 2, the spacer sleeve 4, and the outer sleeve 3 at the joint surface should be set according to the situation of the rubber deformation corresponding to the load with the highest occurrence frequency. When the rubber is deformed under the load with the highest occurrence frequency, all the vertices can be on the same line perpendicular to the load direction. This is an ideal structure. At this time, the load-bearing state of the rubber is the best, and the service life of the rubber can be extended.

[0040] Of course, the thicknesses of the mandrel 1, the rubber body 2, the spacer sleeve 4, and the outer sleeve 3 can be set according to production and assembly requirements. For example, the rubber body 2 and the spacer sleeve 4 can be set to have the same thickness everywhere to simplify the design and processing, while the mandrel 1 and the outer sleeve 3 can be set to have different thicknesses everywhere to meet installation and other requirements. For example, the thicknesses of the mandrel 1 and the outer sleeve 3 are mainly designed according to stiffness and strength, and generally the minimum thickness is above 5 mm; while the thickness of the rubber body 2 is generally designed according to stiffness performance and taking into account reliability, and its total thickness should generally not be less than 3 times the maximum fatigue deformation.

[0041] In addition, the mandrel 1, the spacer sleeve 4, and the outer sleeve 3 at both ends of the rubber spring all extend beyond the rubber body 2 at the joint with them, which is for the convenience of installation and can also prevent the bulging amount of the rubber after being loaded and deformed from exceeding the metal and causing folding, thereby improving the reliability of the rubber spring.

[0042] Meanwhile, as Figure 3 shown, an annular retaining ring 6 is provided on the outer circumference at the bottom of the large end of the mandrel 1, which not only improves the stiffness of the rubber spring but also realizes variable stiffness again, and has a stop function to a certain extent.

[0043] During assembly, the simplest positioning and installation method for the bottom of the rubber spring is to use pin positioning. The bottom of the cavity of the mandrel 1 can be machined into a jack 5 with very high precision, and the jack 5 is in the shape of a horn with a smaller upper part and a larger lower part, and a pin with a smaller upper part and a larger lower part can be set on the axle box to match it. In addition, a threaded hole can be provided at the bottom end of the mandrel 1 or an installation structure can be provided on the outer circumference at the bottom end of the mandrel 1. Of course, it can also be the simultaneous use of pin positioning of the jack 5 and fixing with the threaded hole at the bottom end or fixing with the installation structure on the outer circumference at the bottom end. The fixing of the top of the rubber spring can also be achieved by providing a threaded hole at the top end of the outer sleeve 3 or providing other installation structures on the outer circumference at the top end of the outer sleeve 3. Of course, if the assembly and fixing are carried out by using the method of providing a threaded hole at the end, the thickness at the bottom of the mandrel 1 or the top of the outer sleeve 3 must be able to meet the strength requirements.

[0044] Embodiment 2

[0045] The rubber spring of this embodiment is as Figure 11 shown, and its rubber consists of three sections in the vertical direction. The situation at the joint surface is illustrated by the mandrel 1 in Figure 11 . In the longitudinal sectional view of the joint surface, it consists of three line segments L1, L2, and L3, forming two included angles with two vertices A1 and A2. Similarly, according to the situation of the rubber deformation corresponding to the load with the highest frequency of occurrence, the two vertices A1 and A2 of the mandrel 1, the rubber body 2, the spacer sleeve 4, and the outer sleeve 3 at the joint surface need to be set. When the rubber deforms corresponding to the load with the highest frequency of occurrence, all the vertices A1 and A2 can be respectively on the same line perpendicular to the load direction. If the L1 section of the mandrel 1 is in a vertical state, when vertically loaded, after the rubber body 2 is extruded and deformed to a certain extent, the L3 section of the mandrel 1 provides the vertical stiffness and the first variable stiffness occurs; when the load continues to increase, the rubber body 2 continues to deform, and the L2 section of the mandrel 1 provides the vertical stiffness and the second variable stiffness occurs; when the rubber body 2 continues to deform and presses down to the retaining ring 6 at the bottom end of the mandrel, the L4 section on the upper surface of the retaining ring 6 provides the vertical stiffness and serves as a stop, and the variable stiffness occurs again.

[0046] Similarly, when more variable stiffnesses need to be realized, the mandrel 1, the rubber body 2, the spacer sleeve 4, and the outer sleeve 3 can be set into a structure composed of more sections.

[0047] Embodiment 3

[0048] This embodiment is an improvement on the above embodiments. When the stiffness requirement is not high, the spacer sleeve 4 in Embodiment 1 and Embodiment 2 can be cancelled to form a structure of outer sleeve 3 - rubber body 2 - mandrel 1.

[0049] The above embodiments are only for illustrating the present invention, rather than limiting the present invention. Those skilled in the relevant technical fields can also make various changes or transformations without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions should also fall within the protection scope of the present invention, and the protection scope of the present invention should be defined by each claim.

Claims

1. A special-shaped rubber spring, comprising an inner core shaft, an outer jacket, and a rubber body vulcanized between the core shaft and the jacket, characterized in that: The mandrel, the rubber body and the outer sleeve are all waist-shaped cylinders with one end larger and the other end smaller. The mandrel has a cavity inside, and the cavity of the mandrel is also a waist-shaped cylinder with a large end and a small end. During assembly, the small end is on the top and is connected to the bogie through the outer sleeve, and the large end is on the bottom and is connected to the axle box through the mandrel; the connecting lines of the contact surfaces between the rubber body and the mandrel and the outer sleeve in the longitudinal sectional view are more than two straight line segments, and the connecting lines of the contact surfaces between the rubber body and the mandrel and the outer sleeve at the small end in the longitudinal sectional view are parallel lines; the lateral width of the rubber spring is 140 - 220 mm; A spacer sleeve is arranged vertically inside the rubber body, and both sides of the spacer sleeve are vulcanized and connected to the rubber.

2. The special-shaped rubber spring according to claim 1, wherein: The lateral width of the rubber spring at the small end is 40 - 120 mm, and the lateral width at the large end is 160 - 180 mm.

3. The special-shaped rubber spring according to claim 1, characterized in that: The connecting line consists of two straight line segments, and the included angle between the two straight line segments is 150 - 180 o .

4. The special-shaped rubber spring according to claim 1, wherein: The connecting lines are more than three straight line segments, and the angle between adjacent two straight line segments near the small end is greater than the angle between adjacent two straight line segments near the large end.

5. The special-shaped rubber spring according to claim 4, characterized in that: The spacer sleeve is also a waist-shaped cylinder with one end larger and the other end smaller, and the number of spacer sleeves is set to be more than one according to the stiffness requirement.

6. The special-shaped rubber spring according to claim 1, characterized in that: A retaining ring protruding from the outer circumference at the bottom of the mandrel is provided.

7. A method for adjusting the stiffness of the special-shaped rubber spring according to claim 1, characterized in that: By adjusting the proportion of each section of rubber in the vertical direction of the rubber body, the vertical stiffness of the rubber spring is adjusted.

8. The method for adjusting the stiffness of the special-shaped rubber spring according to claim 7, characterized in that: By adjusting the angle between each section of rubber in the vertical direction of the rubber body, the vertical stiffness of the rubber spring is adjusted.

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