Vibration isolation device and vibration isolation system based on the positive and negative stiffness of cosine curved beam
By connecting a laminated cosine curved beam in parallel within the laminated rubber bearing, the problem of poor vertical vibration isolation performance of the laminated rubber bearing under low-frequency excitation is solved, achieving the effect of improving vertical vibration isolation capability without affecting horizontal vibration isolation performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HARBIN INST OF TECH
- Filing Date
- 2023-11-17
- Publication Date
- 2026-05-26
AI Technical Summary
Existing laminated rubber bearings have poor vertical vibration isolation performance under low-frequency excitation, and increasing the thickness of the rubber layer to reduce the bearing stiffness will affect the horizontal vibration isolation capability.
A positive and negative stiffness parallel vibration isolation device based on a cosine curved beam is adopted. By setting up a laminated cosine curved beam in parallel in a laminated rubber support, and connecting it with the upper connecting plate through a joint, and fixing the limiting column on the lower connecting plate, the laminated cosine curved beam buckles into the negative stiffness section under its own weight, thereby enhancing the vertical vibration isolation capability.
Without affecting the horizontal vibration isolation performance, the vertical vibration isolation capability is improved. The structure is simple, does not yield in the elastic stage, reduces stiffness, and enhances the vibration isolation effect.
Smart Images
Figure CN117605791B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of vibration isolation device technology, specifically to a vibration isolation device and system based on a cosine curved beam with parallel positive and negative stiffness. Background Technology
[0002] Currently, the laminated rubber bearing, a commonly used vertical vibration isolation device for buildings along rail transit lines, has been widely applied due to its certain vertical vibration isolation performance and excellent horizontal vibration isolation performance. However, in the research of many scholars, the vibration isolation effect of laminated rubber bearing under low-frequency excitation still needs to be improved.
[0003] According to general practical requirements, in order to ensure horizontal seismic isolation capability, the thickness of the rubber layer of the laminated rubber bearing cannot be too large. Therefore, increasing the thickness of the rubber layer to form a thick rubber bearing will reduce the bearing stiffness and reduce the horizontal seismic isolation capability. On the premise of not affecting the horizontal seismic isolation performance, a solution to improve the vertical vibration isolation capability still needs to be studied. Summary of the Invention
[0004] Therefore, the technical problem to be solved by the present invention is to overcome the problem that while thick rubber bearings improve vertical vibration isolation capacity, they reduce horizontal vibration isolation capacity, thereby providing a vibration isolation device and vibration isolation system based on a cosine curved beam with parallel positive and negative stiffness.
[0005] To address the aforementioned technical problems, this invention provides a parallel vibration isolation device based on a cosine curved beam with positive and negative stiffness, comprising: a laminated rubber bearing, including an upper connecting plate and a lower connecting plate, wherein a rubber layer and a steel plate layer are disposed between the upper and lower connecting plates and the bearing is located at the center of the upper and lower connecting plates; a fixing structure, disposed on the upper and lower connecting plates and connected in parallel to the outer periphery of the rubber layer and the steel plate layer; a laminated cosine curved beam, comprising multiple pieces, disposed on the fixing structure, wherein the laminated cosine curved beam has a joint, the joint being connected to the upper connecting plate; and a limiting post, disposed on the lower connecting plate, the limiting post being located at the bottom of the laminated cosine curved beam.
[0006] Furthermore, the stacked cosine-shaped curved beam is an elastic element.
[0007] Furthermore, the stacked cosine curved beam includes: a single-layer cosine curved beam having multiple layers stacked together, the single-layer cosine curved beam having a predetermined curvature; and a flat beam disposed at both ends of the single-layer cosine curved beam, the flat beam being connected to the fixed structure.
[0008] Furthermore, the stacked cosine curved beam also includes a metal sheet disposed between two connected single-layer cosine curved beams, and the curvature of the metal sheet is the same as the curvature of the single-layer cosine curved beam.
[0009] Furthermore, the limiting post is located at 1 / 4 of the span of the laminated cosine curved beam.
[0010] Furthermore, the joint includes a metal layer and polytetrafluoroethylene (PTFE), the metal layer being in contact with the upper connecting plate, and the PTFE being in contact with the laminated cosine curved beam.
[0011] Furthermore, the fixing structure includes: a plurality of fixed baffles, wherein a predetermined gap is provided between the plurality of fixed baffles, and the flat beam is disposed within the predetermined gap; and a movable baffle disposed on the fixed baffles, wherein the movable baffle is connected to the lower connecting plate by a fixing member.
[0012] Furthermore, there are two fixing members, which are symmetrically arranged, pass through the movable baffle, and are connected to the lower connecting plate.
[0013] Furthermore, the steel plate layer has multiple layers, and the rubber layer is located between two adjacent steel plate layers.
[0014] The present invention also provides a parallel vibration isolation system based on a cosine curved beam with positive and negative stiffness, including a parallel vibration isolation device based on a cosine curved beam with positive and negative stiffness.
[0015] The technical solution of this invention has the following advantages:
[0016] 1. The present invention provides a parallel vibration isolation device based on a cosine curved beam with positive and negative stiffness, comprising: a laminated rubber support, including an upper connecting plate and a lower connecting plate, wherein a rubber layer and a steel plate layer are provided between the upper connecting plate and the lower connecting plate, and the support is located at the center of the upper connecting plate and the lower connecting plate; a fixing structure, disposed on the upper connecting plate and the lower connecting plate, and disposed in parallel on the outer periphery of the rubber layer and the steel plate layer; a laminated cosine curved beam having multiple pieces, disposed on the fixing structure, wherein a joint is provided on the laminated cosine curved beam, and the joint is connected to the upper connecting plate; and a limiting post, disposed on the lower connecting plate, wherein the limiting post is located at the bottom of the laminated cosine curved beam.
[0017] By setting a rubber layer and a steel plate layer between the upper and lower connecting plates, and the rubber layer, steel plate layer, and lower connecting plate forming a laminated rubber bearing, the first shape factor S1 of the laminated rubber bearing should be greater than 15, thereby ensuring horizontal vibration resistance. Multiple laminated cosine curved beams are fixed to the lower connecting plate by the fixing structure. The upper end of the joint is connected to the upper connecting plate and contacts it through pressure. That is, when a heavy object is placed in the parallel vibration isolation device based on the positive and negative stiffness of the cosine curved beam, the lower end of the joint contacts the laminated cosine curved beam. At the same time, a limiting post is fixed to the lower connecting plate to limit the position of the laminated cosine curved beam.
[0018] In practical applications, appropriate measures should be taken to pre-compress the laminated cosine curved beam so that the laminated cosine curved beam buckles at the static equilibrium position under the action of the superstructure and enters the negative stiffness section. That is, when the positive and negative stiffness parallel vibration isolation device based on the cosine curved beam is placed with heavy objects, the positive and negative stiffness parallel vibration isolation device based on the cosine curved beam is under its own weight so as to play its role.
[0019] The structure of the positive and negative stiffness parallel vibration isolation device based on cosine curved beam is simple. By setting the laminated cosine curved beam in parallel on the outer periphery of the laminated rubber support, the stiffness of the positive and negative stiffness parallel vibration isolation device based on cosine curved beam is reduced while the bearing capacity remains unchanged, thereby increasing the vibration isolation capacity. It also improves the vertical vibration isolation capacity without affecting the horizontal vibration isolation performance.
[0020] 2. The positive and negative stiffness parallel vibration isolation device based on a cosine curved beam provided by the present invention, wherein the stacked cosine curved beam is an elastic element. The elastic element is made of elastic material, and the setting of the elastic element can ensure that the positive and negative stiffness parallel vibration isolation device based on the cosine curved beam is in the elastic stage and does not yield.
[0021] 3. The positive and negative stiffness parallel vibration isolation device based on a cosine curved beam provided by the present invention further includes a metal sheet in the stacked cosine curved beam. The metal sheet is disposed between two connected single-layer cosine curved beams, and the curvature of the metal sheet is the same as that of the single-layer cosine curved beam. Placing a thin metal sheet with the same curvature as the single-layer cosine curved beam at the midpoint between two adjacent single-layer cosine curved beams can effectively reduce interlayer frictional contact.
[0022] The summary section is provided to present the chosen concepts in a simplified form, which will be further described in the detailed description below. The summary section is not intended to identify essential or necessary features of this disclosure, nor is it intended to limit the scope of this disclosure. Attached Figure Description
[0023] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0024] Figure 1 A schematic diagram of the structure of the positive and negative stiffness parallel vibration isolation device based on a cosine curved beam provided by the present invention;
[0025] Figure 2 The front view of the positive and negative stiffness parallel vibration isolation device based on a cosine curved beam provided by the present invention;
[0026] Figure 3 A front view of the positive and negative stiffness parallel vibration isolation device based on a cosine curved beam provided by the present invention during use;
[0027] Figure 4 A schematic diagram of the structure of the stacked cosine curved beam, which is based on the positive and negative stiffness parallel vibration isolation device of the cosine curved beam provided by the present invention;
[0028] Figure 5 This is a schematic diagram of the fixed structure of the positive and negative stiffness parallel vibration isolation device based on a cosine curved beam provided by the present invention.
[0029] Explanation of reference numerals in the attached figures:
[0030] 1. Laminated rubber bearing; 2. Upper connecting plate; 3. Lower connecting plate; 4. Rubber layer; 5. Steel plate layer; 6. Fixing structure; 7. Laminated cosine curved beam; 8. Joint; 9. Limiting column; 10. Single-layer cosine curved beam; 11. Flat beam; 12. Metal sheet; 13. Metal layer; 14. Polytetrafluoroethylene; 15. Fixed baffle; 16. Movable baffle; 17. Fixture. Detailed Implementation
[0031] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of this disclosure. Therefore, the drawings and description are to be considered exemplary in nature and not restrictive.
[0032] In the description of this disclosure, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing this disclosure 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, and therefore should not be construed as a limitation of this disclosure. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this disclosure, "a plurality of" means two or more, unless otherwise explicitly specified.
[0033] In the description of this disclosure, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joint" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections, electrical connections, or connections that allow for communication; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.
[0034] In this disclosure, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0035] The following disclosure provides numerous different embodiments or examples for implementing various structures of this disclosure. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of this disclosure. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, various specific examples of processes and materials are provided in this disclosure, but those skilled in the art will recognize the application of other processes and / or the use of other materials.
[0036] The preferred embodiments of this disclosure are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.
[0037] Please see Figures 1 to 5As shown, the present invention provides a positive and negative stiffness parallel vibration isolation device based on a cosine curved beam, comprising: a laminated rubber support 1 including an upper connecting plate 2 and a lower connecting plate 3, wherein a rubber layer 4 and a steel plate layer 5 are disposed between the upper connecting plate 2 and the lower connecting plate 3 and are located at the center of the upper connecting plate 2 and the lower connecting plate 3, the upper connecting plate 2 and the lower connecting plate 3, the rubber layer 4 and the steel plate layer 5 constituting the laminated rubber support 1; a fixing structure 6 disposed on the upper connecting plate 2 and the lower connecting plate 3 and disposed in parallel on the outer periphery of the rubber layer 4 and the steel plate layer 5; a laminated cosine curved beam 7 having multiple pieces disposed on the fixing structure 6, wherein the laminated cosine curved beam 7 is provided with a joint 8, the joint 8 being connected to the upper connecting plate 2; and a limiting post 9 disposed on the lower connecting plate 3, the limiting post 9 being located at the bottom of the laminated cosine curved beam 7.
[0038] A rubber layer 4 and a steel plate layer 5 are provided between the upper connecting plate 2 and the lower connecting plate 3. The rubber layer 4, the steel plate layer 5, and the lower connecting plate 3 can form a laminated rubber support 1. The first shape factor S1 of the laminated rubber support 1 should be greater than 15, thereby ensuring horizontal vibration isolation capability. Multiple laminated cosine curved beams are fixed to the lower connecting plate 3 by the fixing structure 6. The upper end of the joint 8 is connected to the upper connecting plate 2 and contacts it through pressure. That is, when a heavy object is placed in the parallel vibration isolation device based on the positive and negative stiffness of the cosine curved beam, the lower end of the joint 8 contacts the laminated cosine curved beam 7. At the same time, the limiting post 9 is fixed on the lower connecting plate 3 to limit the position of the laminated cosine curved beam 7.
[0039] In practical applications, appropriate measures should be taken to pre-compress the laminated cosine curved beam so that the laminated cosine curved beam buckles at the static equilibrium position under the action of the superstructure and enters the negative stiffness section. That is, when the positive and negative stiffness parallel vibration isolation device based on the cosine curved beam is placed with heavy objects, the positive and negative stiffness parallel vibration isolation device based on the cosine curved beam is under its own weight so as to play its role.
[0040] The structure of the positive and negative stiffness parallel vibration isolation device based on the cosine curved beam is simple. By setting the laminated cosine curved beam 7 in parallel on the outer periphery of the laminated rubber support 1, the stiffness of the positive and negative stiffness parallel vibration isolation device based on the cosine curved beam is reduced while the bearing capacity remains unchanged, thus increasing the vibration isolation capacity. It also improves the vertical vibration isolation capacity without affecting the horizontal vibration isolation performance.
[0041] The stacked cosine-shaped curved beam is an elastic element. Made of elastic material, this element ensures that the parallel vibration isolation device based on the cosine-shaped curved beam, with both positive and negative stiffnesses, remains in an elastic state and does not yield.
[0042] In some optional embodiments, the stacked cosine curved beam 7 includes: a single-layer cosine curved beam 10 having multiple layers stacked together, the single-layer cosine curved beam 10 having a predetermined curvature; and a flat beam 11 disposed at both ends of the single-layer cosine curved beam 10, the flat beam 11 being connected to the fixed structure 6.
[0043] By setting the flat beam 11, the flat beam 11 on the single-layer cosine curved beam 10 can be inserted into the fixed structure 6. The fixed structure 6 is used to fix the flat beam 11, thereby fixing the single-layer cosine curved beam 10 and the entire stacked cosine curved beam 7. At the same time, the flat beam 11 and the fixed structure 6 must fit tightly to ensure the fixed connection effect. The interlayer surfaces of the multi-layer single-layer cosine curved beam 10 should be smoothed and lubricated to ensure that the negative stiffness of the stacked cosine curved beam has the characteristic of linear superposition, preventing the structural effect from causing an increase in the damping ratio and making it difficult to control the negative stiffness through design.
[0044] In some optional embodiments, the stacked cosine curved beam 7 further includes a metal sheet 12 disposed between two connected single-layer cosine curved beams 10, and the curvature of the metal sheet 12 is the same as that of the single-layer cosine curved beam 10. Placing a thin metal sheet with the same curvature as the single-layer cosine curved beam at the midpoint between two adjacent single-layer cosine curved beams can effectively reduce interlayer frictional contact.
[0045] In some optional embodiments, the limiting post 9 is located at the midpoint of the span of the laminated cosine curved beam. This arrangement effectively limits the laminated cosine curved beam to undergo only third-mode deformation, such as... Figure 3 As shown, by leveraging the characteristics of the third-order modal linear negative stiffness of the cosine curved beam, and based on the principle of positive and negative stiffness, the parallel connection of positive and negative stiffness structures can reduce the dynamic stiffness without changing the static stiffness, thereby improving the vibration isolation frequency domain. At the same time, since the positive stiffness of the laminated rubber support 1 remains unchanged, and the negative stiffness of the laminated cosine curved beam remains unchanged after buckling, the device still exhibits the characteristics of single-degree-of-freedom linear vibration under vibration excitation, and the vibration reduction effect is easy to design and control.
[0046] In some alternative embodiments, the joint 8 includes a metal layer 13 and polytetrafluoroethylene (PTFE) 14, the metal layer 13 contacting the upper connecting plate 2, and the PTFE 14 contacting the laminated cosine curved beam 7. The PTFE 14 layer has high strength and a low coefficient of friction, therefore its horizontal stiffness is only the same as that of the laminated rubber support 1.
[0047] In some optional embodiments, the fixed structure 6 includes: a plurality of fixed baffles 15, wherein a predetermined gap is provided between the plurality of fixed baffles 15, and the flat beam 11 is disposed within the predetermined gap; and a movable baffle 16 disposed on the fixed baffles 15, wherein the movable baffle 16 is connected to the lower connecting plate 3 by a fixing member 17.
[0048] By setting fixed baffles 15 and providing a predetermined gap between multiple fixed baffles 15, it is convenient to place the flat beam 11 within the predetermined gap. Then, a movable baffle 16 is placed on the multiple fixed baffles 15. Finally, the movable baffle 16, the fixed baffles 15, and the flat beam 11 are fixed by the fastener 17, thereby driving the laminated cosine curved beam 7 and achieving end-fixed constraint of the laminated cosine curved beam 7. Before the flat beam 11 is inserted into the predetermined gap, the surface of the single-layer cosine curved beam 10 needs to be polished smooth and lubricated.
[0049] In some optional embodiments, there are two fixing members 17, which are symmetrically arranged and pass through the movable baffle 16 and are connected to the lower connecting plate 3. The fixing members 17 can fix the movable baffle 16, the fixed baffle 15, and the flat beam 11, thereby driving the laminated cosine curved beam 7 and achieving end-fixed constraint of the laminated cosine curved beam 7.
[0050] Among them, fastener 17 is a bolt.
[0051] In some optional embodiments, the steel plate layer 5 has multiple layers, and the rubber layer 4 is located between two adjacent steel plate layers 5. The number of rubber layers 4 and steel plate layers 5 can be set according to actual conditions.
[0052] The present invention also provides a parallel vibration isolation system based on a cosine curved beam with positive and negative stiffness, including the aforementioned parallel vibration isolation device based on a cosine curved beam with positive and negative stiffness.
[0053] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.
Claims
1. A positive and negative stiffness parallel vibration isolation device based on a cosine-shaped curved beam, characterized in that, include: The laminated rubber bearing (1) includes an upper connecting plate (2) and a lower connecting plate (3), with multiple rubber layers (4) and steel plate layers (5) provided between the upper connecting plate (2) and the lower connecting plate (3), and located at the center of the upper connecting plate (2) and the lower connecting plate (3); A fixing structure (6) is provided on the lower connecting plate (3) and is provided in parallel on the outer periphery of the rubber layer (4) and the steel plate layer (5); The laminated cosine curved beam (7) has multiple pieces, which are disposed on the fixed structure (6) and positioned between the two fixed structures (6). The laminated cosine curved beam (7) is provided with a joint (8), which is connected to the upper connecting plate (2). A limiting post (9) is provided on the lower connecting plate (3), and the limiting post (9) is located at the bottom of the stacked cosine curved beam (7).
2. The parallel vibration isolation device with positive and negative stiffness based on a cosine-shaped curved beam according to claim 1, wherein The laminated cosine curved beam (7) is an elastic element.
3. The parallel vibration isolation device with positive and negative stiffness based on a cosine-shaped curved beam according to claim 2, wherein The laminated cosine curved beam (7) includes: A single-layer cosine curved beam (10) has multiple layers, which are stacked together, and the single-layer cosine curved beam (10) has a predetermined curvature; A flat beam (11) is provided at both ends of the single-layer cosine curved beam (10), and the flat beam (11) is connected to the fixed structure (6).
4. The parallel positive and negative stiffness vibration isolation device based on a cosine-shaped curved beam according to claim 3, characterized in that, The stacked cosine curved beam (7) also includes a metal sheet (12), which is disposed between two connected single-layer cosine curved beams (10), and the curvature of the metal sheet (12) is the same as that of the single-layer cosine curved beam (10).
5. The parallel vibration isolation device with positive and negative stiffness based on a cosine-shaped curved beam according to claim 3 or 4, characterized in that The limiting column (9) is located at 1 / 4 of the span of the laminated cosine curved beam.
6. The parallel vibration isolation device with positive and negative stiffness based on a cosine-shaped curved beam according to claim 5, wherein The connector (8) includes a metal layer (13) and polytetrafluoroethylene (14), the metal layer (13) being in contact with the upper connecting plate (2) and the polytetrafluoroethylene (14) being in contact with the laminated cosine curved beam (7).
7. The parallel vibration isolation device with positive and negative stiffness based on a cosine-shaped curved beam according to claim 6, characterized in that, The fixing structure (6) includes: The fixed baffle (15) has multiple fixed baffles (15) and a predetermined gap is provided between the multiple fixed baffles (15), and the flat beam (11) is provided in the predetermined gap; A movable baffle (16) is disposed on the fixed baffle (15), and the movable baffle (16) is connected to the lower connecting plate (3) through a fixing member (17).
8. The parallel positive and negative stiffness vibration isolation device based on a cosine-shaped curved beam according to claim 7, characterized in that, There are two fixing members (17), which are symmetrically arranged and pass through the movable baffle (16) and are connected to the lower connecting plate (3).
9. The parallel positive and negative stiffness vibration isolation device based on a cosine-shaped curved beam according to any one of claims 6-8, wherein The steel plate layer (5) has multiple layers, and the rubber layer (4) is located between two adjacent steel plate layers (5).
10. A parallel vibration isolation system with positive and negative stiffness based on a cosine curved beam, characterized in that, The invention includes the positive and negative stiffness parallel vibration isolation device based on a cosine curved beam as described in any one of claims 1-9.