A longitudinally high dynamic-static ratio liquid composite rubber stack

Abstract

A liquid composite rubber stack with high dynamic-static ratio in longitudinal direction, comprising a top plate, a partition plate and a bottom plate stacked in sequence, an upper rubber layer connected between the top plate and the partition plate, a lower rubber layer connected between the partition plate and the bottom plate, an upper hydraulic chamber and a lower hydraulic chamber with hollows in the upper rubber layer and the lower rubber layer respectively, and a liquid passage communicated between the upper hydraulic chamber and the lower hydraulic chamber, the upper hydraulic chamber and the lower hydraulic chamber extending along the longitudinal direction. The liquid composite rubber stack proposed by the application can stretch on one side and compress on the other side when loaded in the longitudinal direction, fluid exchange occurs to generate damping, low static stiffness and high dynamic stiffness in the longitudinal direction are realized, and the dynamic-static ratio has little influence on the vertical and lateral stiffness.

Description

Technical Field

[0001] This invention relates to the field of vibration reduction devices for rail transit vehicles, specifically a longitudinal liquid composite rubber stack with a high dynamic-to-static ratio. Background Technology

[0002] Rubber stacks are used in the primary traction systems of subway and low-floor urban rail vehicles to transmit vehicle starting and braking forces, as well as lateral and vertical forces. Existing rubber stack structures include... Figure 1 The current structure employs a traditional laminated rubber stack structure, bearing longitudinal traction loads in the compression direction and vertical and lateral loads in the shear direction. The matching of stiffness in these three directions is subject to certain limitations. The shear direction needs to be as small as possible to provide high flexibility, while the longitudinal traction (i.e., the compression direction of the rubber stack) requires the rubber stack to provide low static stiffness and high dynamic stiffness, with lower stiffness at low frequencies and higher stiffness at high frequencies. The existing structure must ensure high longitudinal and low vertical / lateral static stiffness, and the number of layers should not be excessive (5-6 layers) to avoid the risk of instability due to excessive layers. The current structure suffers from poor matching of longitudinal and vertical / lateral stiffness, and the rubber used has relatively low hardness, posing certain application risks.

[0003] A search revealed existing technical documents related to rubber stacks. For example, the invention patent publication number "CN113294483A" entitled "Rubber Stack Built-in Longitudinal Hydraulic Vibration Damping Device and Method" discloses a rubber stack built-in longitudinal hydraulic vibration damping device, belonging to the field of train vibration damping technology. It includes a rubber stack, a top plate and a bottom plate respectively disposed on the top and bottom surfaces of the rubber stack; it also includes a hydraulic damping mechanism disposed within the top plate, a movable cavity disposed within the rubber stack, and a lever mechanism connecting the bottom plate and the damping mechanism through the movable cavity; the damping mechanism includes a piston, a flexible front liquid chamber and a rear liquid chamber filled with damping fluid, the piston being located between the front and rear liquid chambers, and a damping hole on the piston connecting the front and rear liquid chambers. This prior art document solves the technical problem of poor vibration damping effect due to excessive elastic stiffness and weak restoring force attenuation in traditional rubber stacks, but it does not propose a technical solution for the high dynamic-to-static ratio of longitudinal stiffness.

[0004] For example, the invention patent publication document with publication number "CN116951029A" entitled "A Method for Adjusting the Oriented Stiffness and Reducing Vibration of a Rubber Stack" discloses a method for adjusting the directional stiffness of a rubber stack. This method involves vertically arranging longitudinal holes with rectangular cross-sections affecting both lateral and vertical stiffness, with the length direction of the rectangle aligned with the running direction, and vertically arranging transverse holes with rectangular cross-sections affecting both longitudinal and vertical stiffness, with the length direction of the rectangle perpendicular to the running direction. Elastic fillers, set as needed, are inserted into the longitudinal and transverse holes to adjust the stiffness of the rubber stack in a specified direction. This prior art document allows for convenient adjustment of the stiffness of the rubber stack in a specified direction by replacing the elastic fillers, but it does not yet achieve a high dynamic-to-static ratio of longitudinal stiffness.

[0005] Therefore, it is of great significance to propose a liquid composite rubber stack with high dynamic-to-static ratio in longitudinal stiffness in this field. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a longitudinally high dynamic-to-static ratio liquid composite rubber stack, comprising a top plate, a partition plate, and a bottom plate stacked sequentially, an upper rubber layer connecting the top plate and the partition plate, and a lower rubber layer connecting the partition plate and the bottom plate. The upper and lower rubber layers each have a hollow upper hydraulic chamber and a lower hydraulic chamber, respectively, and a liquid channel connects the upper and lower hydraulic chambers. The upper and lower hydraulic chambers extend longitudinally.

[0007] Furthermore, the upper opening of the upper hydraulic chamber is adjacent to the top plate and extends longitudinally into the interior of the upper rubber layer, and the lower opening of the lower hydraulic chamber is adjacent to the bottom plate and extends longitudinally into the interior of the lower rubber layer. The upper hydraulic chamber and the lower hydraulic chamber are mirror-symmetrical with respect to the partition.

[0008] Furthermore, the upper hydraulic chamber and the lower hydraulic chamber are conical, with the inner diameter of the upper hydraulic chamber gradually decreasing from the top plate to the partition, and the inner diameter of the lower hydraulic chamber gradually decreasing from the bottom plate to the partition.

[0009] Furthermore, the sidewalls of both the upper and lower hydraulic chambers are arc-shaped concave surfaces.

[0010] Furthermore, the concave surface of the arc is formed by the transition between arc segment one and arc segment two, wherein the radius relationship between arc segment one and arc segment two is 5R2≥R1≥4R2.

[0011] Furthermore, both the upper and lower hydraulic chambers contain stop members, which can contact the top plate, partition, or bottom plate when the upper and lower rubber layers are longitudinally compressed.

[0012] Furthermore, the stop is a hollow stop rod that penetrates the partition and extends into the upper and lower hydraulic chambers. The hollow stop rod has an external thread in the middle and is assembled and connected to the partition through the external thread. The hollow column in the center of the hollow stop rod forms a liquid channel.

[0013] Furthermore, the side wall of the hollow stop bar has a through groove or through hole that communicates with the hollow column.

[0014] Alternatively, the stop member is a hollow stop post connected to the partition plate, the partition plate has a through hole, and the hollow post in the center of the hollow stop post is connected to the through hole to form a liquid channel; the side wall of the hollow stop post has a through groove or through hole connected to the hollow post.

[0015] Alternatively, the bottom surfaces of both the upper and lower hydraulic chambers are adjacent to the partition plate, and the stop is a stop block connected to the top plate or the bottom plate.

[0016] Compared with the prior art, the technical solution of this application has the following beneficial effects: The liquid composite rubber stack proposed in this invention, when subjected to longitudinal load, has one side of the hydraulic cavity stretched and the other side compressed, resulting in fluid exchange and damping, thus achieving the effect of low static stiffness and high dynamic stiffness in the longitudinal direction; the hydraulic cavity occupies part of the rubber space, which can weaken the longitudinal stiffness, vertical stiffness and lateral stiffness of the original solid structure rubber stack, thus providing a larger space for the adjustment of rubber hardness, and can improve the rubber hardness to reach its optimal functional hardness range; due to the synchronous movement of the rubber stack, the liquid does not flow and exchange in the two shear-dominated loading forms of vertical and lateral directions, that is, the liquid does not produce a damping effect in the vertical and lateral directions, thus achieving a high dynamic-to-static ratio of longitudinal stiffness while having a small impact on the dynamic-to-static ratio of vertical and lateral stiffness. Attached Figure Description

[0017] Figure 1 Schematic diagram of the rubber stack structure Figure 1 ; Figure 2 Schematic diagram of the rubber stack structure Figure 2 ; Figure 3 : A partial structural diagram of the hydraulic chamber; Figure 4 Schematic diagram of the stop component Figure 1 ; Figure 5 Schematic diagram of the stop component Figure 2 ; Figure 6 Schematic diagram of the stop component Figure 3 ; Figure 7 Schematic diagram of the stop component Figure 4 ; Figure 8 Schematic diagram of the stop component Figure 5 . Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] like Figure 2 As shown, a longitudinally high dynamic-to-static ratio liquid composite rubber stack includes a top plate 1, a partition plate 2, and a bottom plate 8 stacked sequentially. An upper rubber layer 31 is connected between the top plate 1 and the partition plate 2, and a lower rubber layer 32 is connected between the partition plate 2 and the bottom plate 8. The upper rubber layer 31 and the lower rubber layer 32 each have a hollow upper hydraulic chamber 51 and a lower hydraulic chamber 52, respectively. A liquid channel 6 connects the upper hydraulic chamber 51 and the lower hydraulic chamber 52, and the upper hydraulic chamber 51 and the lower hydraulic chamber 52 extend longitudinally.

[0020] In this embodiment, the rubber layer is formed by multiple layers of rubber-spaced metal plates, with four layers arranged in pairs. When the product is loaded longitudinally after installation, the upper hydraulic chamber 51 and the lower hydraulic chamber 52 deform in a compression-tension manner, with the liquid inside undergoing flow exchange through the liquid channel 6, generating damping. Therefore, the rubber stack has low static stiffness under longitudinal static load. However, when subjected to longitudinal dynamic load at a high frequency, the upper hydraulic chamber 51 and the lower hydraulic chamber 52 do not have enough time for flow exchange. Due to the incompressibility of the liquid, the dynamic longitudinal stiffness is high under dynamic load, thus achieving a high dynamic-to-static ratio of longitudinal stiffness. When subjected to lateral or vertical loads, the upper rubber layer 31 and the lower rubber layer 32 undergo shear deformation synchronously, so no liquid flow damping is generated internally, resulting in minimal impact on stiffness in the lateral or vertical directions.

[0021] In a typical implementation, the upper opening 53 of the upper hydraulic chamber 51 is adjacent to the top plate 1 and extends longitudinally into the interior of the upper rubber layer 31, and the lower opening 54 of the lower hydraulic chamber 52 is adjacent to the bottom plate 8 and extends longitudinally into the interior of the lower rubber layer 32. The upper hydraulic chamber 51 and the lower hydraulic chamber 52 are mirror-symmetrical with respect to the partition 2.

[0022] In a more preferred embodiment, the upper hydraulic chamber 51 and the lower hydraulic chamber 52 are conical. The inner diameter of the upper hydraulic chamber 51 gradually decreases from the top plate 1 to the partition 2, and the inner diameter of the lower hydraulic chamber 52 gradually decreases from the bottom plate 8 to the partition 2. The conical shape of the hydraulic chambers results in a larger deformation in the initial stage when subjected to longitudinal loads, leading to greater fluid flow and exchange, and thus lower static longitudinal stiffness.

[0023] In a more preferred embodiment, the sidewalls of both the upper hydraulic chamber 51 and the lower hydraulic chamber 52 are arc-shaped concave surfaces. The arc-shaped concave surfaces provide better compression deformation space when the upper rubber layer 31 or the lower rubber layer 32 is compressed and deformed due to longitudinal loads. The volume changes of the upper hydraulic chamber 51 and the lower hydraulic chamber 52 are relatively large, thus the relatively simple straight or inclined surfaces have lower static longitudinal stiffness.

[0024] like Figure 3 As shown, in a more preferred embodiment, the concave arc-shaped surface is formed by a transition between arc segment one and arc segment two, wherein the radii of arc segment one and arc segment two are related as 5R2≥R1≥4R2. That is, the internal surface of the hydraulic chamber is a transition between a large circular arc surface and a small circular arc surface. In the initial stage of longitudinal loading, arc segment one has a larger radius, so its surface angle is relatively gentle. At this time, the compression deformation of the rubber layer has sufficient release space, and the internal volume change of the hydraulic chamber is therefore large, resulting in very small longitudinal static stiffness. After the compression deformation of arc segment one is completed, the subsequent arc segment two, due to its smaller radius, is relatively steep. Similarly, the longitudinal static stiffness is relatively large at this time, thus achieving a nonlinear change in longitudinal static stiffness. In the above embodiment, based on the hysteresis of liquid flow under dynamic longitudinal load and the incompressibility of the liquid, the impact on dynamic stiffness is small, and it still has a large dynamic longitudinal stiffness.

[0025] Based on the above-described implementation method, both the upper hydraulic chamber 51 and the lower hydraulic chamber 52 include stop members. These stop members can contact the top plate 1, the partition 2, or the bottom plate 8 when the upper rubber layer 31 and the lower rubber layer 32 are longitudinally compressed. The purpose of the stop members is to achieve hard contact between the stop members and the top plate 1, the partition 2, or the bottom plate 8 when subjected to large longitudinal loads, thereby realizing a non-linear increase in longitudinal stiffness and preventing damage to the liquid composite rubber stack under large longitudinal loads.

[0026] One implementation method can be as follows: Figures 5-7As shown. The stop component is a hollow stop rod 7 that penetrates the partition 2 and extends into the upper hydraulic chamber 51 and the lower hydraulic chamber 52. The hollow stop rod 7 has an external thread 73 in its middle. The hollow stop rod 7 is assembled and connected to the partition 2 through the external thread 73. The hollow column 71 in the center of the hollow stop rod 7 forms a liquid channel 6. When the upper hydraulic chamber 51 and the lower hydraulic chamber 52 are subjected to excessive longitudinal load and deformation, the end face of the hollow stop rod 7 can contact the top plate 1 or the bottom plate 8, achieving a non-linear increase in longitudinal stiffness. Under normal longitudinal load, the hollow column 71 in the center of the hollow stop rod 7 can act as a liquid channel 6 to allow liquid exchange between the upper hydraulic chamber 51 and the lower hydraulic chamber 52. The hollow stop rod 7 is connected to the partition 2 through the external thread 73, which is simple and convenient to assemble and can prevent the hollow stop rod 7 from loosening.

[0027] To further reduce the damping of the liquid flow inside the hollow stop rod 7, a through groove 72 or through hole 74 communicating with the hollow column 71 is provided on the side wall of the hollow stop rod 7. Liquid exchange between the upper hydraulic chamber 51 and the lower hydraulic chamber 52 can enter the hollow column 71 through the through groove 72 or through hole 74, resulting in even lower liquid flow damping.

[0028] Similar to the above implementation methods, such as Figure 8 As shown. The stop component is a hollow stop post 9 connected to the partition plate 2. The partition plate 2 has a through hole 21. The hollow post 92 in the center of the hollow stop post 9 communicates with the through hole 21 to form a liquid channel 6. The side wall of the hollow stop post 9 has a through groove 91 or a through hole 93 communicating with the hollow post 92. Compared with the hollow stop rod 7, the hollow stop post 9 is split and is respectively set in the upper hydraulic chamber 51 and the lower hydraulic chamber 52, and its bottom surface is connected to the partition plate 2.

[0029] Another implementation of the stop is as follows: Figure 4 As shown, the bottom surfaces of the upper hydraulic chamber 51 and the lower hydraulic chamber 52 are adjacent to the partition plate 2, and the stop is a stop block 11 connected to the top plate 1 or the bottom plate 8. When the longitudinal load is too large, the end face of the stop block 11 can contact the partition plate (2) to achieve a nonlinear increase in longitudinal stiffness.

[0030] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0031] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A longitudinally high dynamic-to-static ratio liquid composite rubber stack, comprising a top plate (1), a partition plate (2), and a bottom plate (8) stacked sequentially, wherein an upper rubber layer (31) is connected between the top plate (1) and the partition plate (2), and a lower rubber layer (32) is connected between the partition plate (2) and the bottom plate (8), characterized in that, The upper rubber layer (31) and the lower rubber layer (32) have hollow upper hydraulic chambers (51) and lower hydraulic chambers (52) respectively, and a liquid channel (6) is connected between the upper hydraulic chambers (51) and the lower hydraulic chambers (52). The upper hydraulic chambers (51) and the lower hydraulic chambers (52) extend longitudinally. When the longitudinal dynamic load is high, the upper hydraulic chambers (51) and the lower hydraulic chambers (52) do not have time to exchange flow. Due to the incompressibility of the liquid, the dynamic longitudinal stiffness is high under the dynamic load, thereby achieving a high dynamic-to-static ratio of longitudinal stiffness.

2. The longitudinally high dynamic-to-static ratio liquid composite rubber stack as described in claim 1, characterized in that, The upper opening (53) of the upper hydraulic chamber (51) is adjacent to the top plate (1) and extends longitudinally into the interior of the upper rubber layer (31). The lower opening (54) of the lower hydraulic chamber (52) is adjacent to the bottom plate (8) and extends longitudinally into the interior of the lower rubber layer (32). The upper hydraulic chamber (51) and the lower hydraulic chamber (52) are mirror-symmetrical relative to the partition (2).

3. The longitudinally high dynamic-to-static ratio liquid composite rubber stack as described in claim 2, characterized in that, The upper hydraulic chamber (51) and the lower hydraulic chamber (52) are conical. The inner diameter of the upper hydraulic chamber (51) gradually decreases from the top plate (1) to the partition plate (2), and the inner diameter of the lower hydraulic chamber (52) gradually decreases from the bottom plate (8) to the partition plate (2).

4. The longitudinally high dynamic-to-static ratio liquid composite rubber stack as described in claim 3, characterized in that, The sidewalls of the upper hydraulic chamber (51) and the lower hydraulic chamber (52) are both arc-shaped concave surfaces.

5. The longitudinally high dynamic-to-static ratio liquid composite rubber stack as described in claim 4, characterized in that, The concave arc-shaped surface is formed by the transition between arc segment one and arc segment two, wherein the radius relationship between arc segment one and arc segment two is 5R2≥R1≥4R2.

6. The longitudinally high dynamic-to-static ratio liquid composite rubber stack as described in any one of claims 1 to 5, characterized in that, Both the upper hydraulic chamber (51) and the lower hydraulic chamber (52) contain stop members. When the upper rubber layer (31) and the lower rubber layer (32) are longitudinally compressed, the stop members can contact the top plate (1), the partition (2), or the bottom plate (8).

7. The longitudinally high dynamic-to-static ratio liquid composite rubber stack as described in claim 6, characterized in that, The stop is a hollow stop rod (7) that passes through the partition (2) and extends into the upper hydraulic chamber (51) and the lower hydraulic chamber (52). The hollow stop rod (7) has an external thread (73) in the middle. The hollow stop rod (7) is assembled and connected to the partition (2) through the external thread (73). The hollow column (71) in the center of the hollow stop rod (7) forms a liquid channel (6).

8. The longitudinally high dynamic-to-static ratio liquid composite rubber stack as described in claim 7, characterized in that, The hollow stop bar (7) has a through groove (72) or through hole (74) on its side wall that communicates with the hollow column (71).

9. The longitudinally high dynamic-to-static ratio liquid composite rubber stack as described in claim 6, characterized in that, The stop is a hollow stop post (9) connected to the partition (2). The partition (2) has a through hole (21). The hollow post (9) in the center of the hollow stop post (9) and the through hole (21) are connected to form a liquid channel (6). The side wall of the hollow stop post (9) has a through groove (91) or a through hole (93) connected to the hollow post (92).

10. The longitudinally high dynamic-to-static ratio liquid composite rubber stack as described in claim 6, characterized in that, The bottom surfaces of the upper hydraulic chamber (51) and the lower hydraulic chamber (52) are adjacent to the partition plate (2), and the stop is a stop block (11) connected to the top plate (1) or the bottom plate (8).

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