Multidirectional two-stage buckling beam type quasi-zero stiffness vibration isolator and use method

Abstract

The invention discloses a multidirectional two-stage buckling beam type quasi-zero stiffness vibration isolator which comprises multiple layers of support assemblies, a buckling beam type connecting structure is arranged between the multiple layers of support assemblies, and the buckling beam type connecting structure comprises a plurality of first-stage buckling beams, a plurality of second-stage buckling beams and a plurality of third-stage buckling beams. The plurality of first-stage buckling beams are connected between the upper supporting seat and the connecting seat and are used for providing first-stage bearing and quasi-zero stiffness effect; the buckling beam type connecting structure further comprises a plurality of second-stage buckling beams, the second-stage buckling beams are connected between the connecting base and the lower base and are arranged in different directions, through two-stage series connection and a spatial multi-direction buckling beam structure, the high static bearing capacity and the unbalance loading resistance are guaranteed, and meanwhile the buckling beam type connecting structure has the advantages that the buckling beam type connecting structure is simple in structure, convenient to operate and high in practicability. A wider quasi-zero stiffness interval and excellent ultra-low frequency and multi-dimensional vibration isolation performance are achieved, the stable and reliable structure is ensured through the controllable buckling design, and accurate optimization and productization are facilitated through parameterized geometric configuration.

Description

Technical Field

[0001] This invention relates to the field of low-frequency vibration isolation technology, and in particular to a multi-directional two-stage buckling beam quasi-zero stiffness vibration isolator and its usage method. Background Technology

[0002] Despite significant research achievements in the current quasi-zero stiffness vibration isolator research and market, issues such as a narrow quasi-zero stiffness range and insufficient load-bearing capacity remain. Because quasi-zero stiffness vibration isolation systems possess excellent low-frequency vibration isolation performance, while traditional vibration isolation methods have significant limitations in low-frequency isolation, several important fields have an urgent need for low-frequency and ultra-low-frequency vibration isolation. Summary of the Invention

[0003] This invention aims to address the shortcomings of existing technologies by providing a multi-directional secondary buckling beam quasi-zero stiffness vibration isolator and its usage method. This addresses the technical problems commonly found in existing quasi-zero stiffness vibration isolators, such as narrow low stiffness range, contradiction between load-bearing and vibration isolation performance, weak multi-dimensional vibration isolation capability, and insufficient structural stability and compactness.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a multi-directional two-stage buckling beam quasi-zero stiffness vibration isolator, comprising a multi-layer support assembly, wherein the multi-layer support assembly has at least three layers, including an upper support, a connecting seat, and a lower base from top to bottom. A buckling beam connection structure is provided between the multi-layer support assemblies. The buckling beam connection structure includes a plurality of first-stage buckling beams, which are connected between the upper support and the connecting seat and arranged in different directions to provide first-stage load-bearing and quasi-zero stiffness effects. The buckling beam connection structure also includes a plurality of second-stage buckling beams, which are connected between the connecting seat and the lower base and arranged in different directions to provide second-stage load-bearing and quasi-zero stiffness effects.

[0005] Preferably, the number of first-stage buckling beams is at least six, and the first-stage buckling beams are evenly distributed around the central axis of the upper support and the connecting seat.

[0006] Preferably, the number of second-stage buckling beams is at least eight, and the second-stage buckling beams are evenly distributed around the central axis of the connecting seat and the lower base.

[0007] Preferably, both the first-stage buckling beam and the second-stage buckling beam are elastic beams with specific geometric configurations, which include a smooth cosine-curved beam structure and a circular arc beam structure.

[0008] Preferably, the upper support, connecting seat, and lower base are rigid structures used to constrain the lateral displacement range of the ends of the first-stage buckling beam and the second-stage buckling beam.

[0009] Preferably, both the first-stage buckling beam and the second-stage buckling beam are elastic beams.

[0010] Preferably, the circular arc beam structure and the cosine curved beam structure are integrally formed, and the cosine curved beam structure and the circular arc beam structure of the first-stage buckling beam are respectively connected to the upper support and the connecting seat; the cosine curved beam structure and the circular arc beam structure of the second-stage buckling beam are respectively connected to the connecting seat and the lower base.

[0011] Preferably, the buckling beam connection structure is made of spring steel.

[0012] Preferably, the multi-layer support assembly and the buckling beam connection structure are made of metallic materials.

[0013] Preferably, the present invention also relates to a method of using a multi-directional two-stage buckling beam quasi-zero stiffness vibration isolator, comprising the following steps: S1: When the upper support is subjected to external pressure, it tends to displace downwards. At this time, the buckling beam undergoes bending deformation under vertical pressure, and its internal stress gradually increases. When the critical buckling load is reached, six buckling beams begin to buckle and produce lateral displacement. The connecting seat and the lower base work together to limit the expansion range of this lateral displacement, so that the buckling beam undergoes controllable buckling deformation only within a preset space, thereby consuming external excitation energy and achieving the first-level load-bearing and vibration reduction effect. S2: When the connecting seat is subjected to the pressure of the first-level buckling, the upper support and the connecting seat tend to displace downwards. At this time, the buckling beam undergoes bending deformation under vertical pressure, and its internal stress gradually increases. When the critical buckling load is reached, eight buckling beams begin to buckle and produce lateral displacement. The connecting seat and the lower base work together to limit the expansion range of this lateral displacement, so that the buckling beam undergoes controllable buckling deformation only within a preset space, thereby consuming external excitation energy and achieving the second-level load-bearing and vibration reduction effect.

[0014] Beneficial effects of this invention: 1. It broadens the effective vibration isolation frequency band and improves the low-frequency vibration isolation performance: Through the "two-stage series" design, it achieves a two-stage or wider quasi-zero stiffness range, enabling the vibration isolator to maintain extremely low dynamic stiffness in a larger range of load changes or vibration amplitude, thereby more effectively isolating ultra-low frequency vibrations. 2. Significantly improved load-bearing capacity and load adaptability: The "multi-level" structure distributes the total load, and the "multi-directional" (14 beams) layout greatly enhances the static load-bearing capacity and resistance to eccentric loads of the structure, enabling it to support heavier equipment and maintain stable operation under unbalanced pressure. 3. Excellent multi-dimensional vibration isolation effect is achieved: The 6+8 spatial multi-directional arrangement enables the vibration isolator to not only effectively isolate vertical vibration, but also isolate horizontal and all-directional coupled vibration, making it suitable for complex actual vibration environments. 4. Enhanced structural stability and reliability: The constraint design of the connecting seat and base ensures that buckling deformation is controllable and recoverable, avoiding structural instability and failure. The two-stage structure also provides a redundant safety mechanism; even if the first stage fails, the second stage can still provide basic functions. 5. It provides a technical approach for precise design and optimization: the shape of the buckling beam is precisely defined by mathematical formulas (cosine function and circle equation), which enables the performance prediction and optimization of the design through theoretical calculation and finite element analysis, improving the scientific nature and repeatability of the design and facilitating productization. Attached Figure Description

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0016] Figure 1 Schematic diagram of a multi-directional buckling beam quasi-zero stiffness vibration isolator Figure 1 ; Figure 2 Schematic diagram of a multi-directional buckling beam quasi-zero stiffness vibration isolator Figure 2 ; Figure 3 Schematic diagram of a buckling beam structure; Figure 4 Static performance verification diagram of buckling beam structural element; In the figure: upper support 10, connecting seat 30, lower base 50, first-stage buckling beam 20, second-stage buckling beam 40, circular arc beam structure 210, cosine curved beam structure 220; The number of first-order buckling beams is six, ranging from 201 to 206; the number of second-order buckling beams is eight, ranging from 401 to 408. Detailed Implementation

[0017] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0018] like Figure 1-4As shown, a multi-directional two-stage buckling beam quasi-zero stiffness vibration isolator includes a multi-layer support assembly. The multi-layer support assembly has at least three layers, from top to bottom including an upper support 10, a connecting seat 30, and a lower base 50. A buckling beam connection structure is provided between the multi-layer support assemblies. The buckling beam connection structure includes several first-stage buckling beams 20, which are connected between the upper support 10 and the connecting seat 30 and arranged in different directions to provide first-stage load-bearing and quasi-zero stiffness effects. The buckling beam connection structure also includes several second-stage buckling beams 40, which are connected between the connecting seat 30 and the lower base 50 and arranged in different directions to provide second-stage load-bearing and quasi-zero stiffness effects. In this embodiment, the invention decomposes the vibration isolation system into a multi-layer structure through an innovative "two-stage series" architecture, preferably a three-layer structure. The upper support 10, connecting seat, and lower base 50 are connected in series. The first-stage buckling beam constitutes the primary load-bearing and initial vibration isolation layer, while the connecting seat-lower base-second-stage buckling beam constitutes the secondary load-bearing and extended vibration isolation layer. This design provides high static stiffness through the parallel connection of two elastic beams to stably support the load in a static state. Under dynamic excitation, the two-stage buckling beams can enter a controlled buckling state sequentially or collaboratively, generating a negative stiffness effect. This allows the total dynamic stiffness of the system to approach zero (i.e., quasi-zero stiffness) over a wider displacement range, greatly expanding the effective working range of traditional quasi-zero stiffness vibration isolators and improving multi-directional vibration suppression capabilities. Specifically, when the upper support 10 is compressed, the load-bearing capacity and quasi-zero stiffness characteristics provided by the six buckling beams 20 in different directions between the upper support 10 and the connecting seat 30 achieve the first-stage load-bearing and vibration reduction effect; then, the load-bearing capacity and quasi-zero stiffness characteristics provided by the eight buckling beams 40 in different directions between the connecting seat 30 and the lower base 50 achieve the second-stage load-bearing and vibration reduction effect. The specific connection relationship in this embodiment is as follows: First, as shown in the diagram... Figure 1 The support base 10 shown in this application is a hexagonal support base. The connecting base 30 is a connecting frame with an octagonal outer side and a hexagonal inner side. The lower base 50 is a frame with a dodecagonal outer side and an octagonal inner side. Therefore, during installation, there are six first-stage buckling beams 20. The cosine-shaped curved beam segments 220 of the first-stage buckling beams 20 are connected to the six outer sides of the support base 10, specifically to the center position of the outer side of the support base 10. At the same time, the arc segment structure 210 of the first-stage buckling beams 20 is connected to the six inner sides of the connecting base 30. The cosine-shaped curved beam segments 220 of the eight second-stage buckling beams 40 are connected to the eight outer sides of the connecting base 30, while the second-stage buckling beams 40 are connected to the eight inner sides of the lower base 50. In this embodiment, the connection between the first-stage buckling beams 20 and the second-stage buckling beams 40 is a conventional technical means in the art, and a fixed connection can be achieved by welding or slotted insertion.

[0019] Preferably, the number of first-stage buckling beams 20 is at least six, and the first-stage buckling beams 20 are evenly distributed around the central axis of the upper support seat 10 and the connecting seat 30. In this embodiment, setting at least six first-stage buckling beams and distributing them evenly around the circumference is mainly to ensure the symmetry of the load distribution, avoid local buckling beam overload failure caused by eccentric loading, thereby improving the load-bearing stability and reliability of the entire first-stage subsystem. Six directions are the minimum preferred number that can provide stable and symmetrical support. At the same time, this application can also use eight or ten vertical beams that simultaneously adjust the second-stage buckling beams.

[0020] Preferably, the number of second-stage buckling beams 40 is at least eight, and the second-stage buckling beams 40 are evenly distributed around the central axis of the connecting seat 30 and the lower base 50; in this embodiment, the second-stage buckling beams are set to at least eight and evenly distributed circumferentially, such as... Figure 1 , 2 As shown, the second-stage buckling beams, which are more numerous than the first-stage beams, primarily enhance overall stability and redundancy. More support points allow for a more even distribution of the load transferred from the first stage, reducing localized stress in the connecting seats and lower base. Furthermore, the greater number of second-stage buckling beams provides finer stiffness adjustment. By fine-tuning their geometric or material parameters, the increased number of buckling beams can more precisely shape the force-displacement curve of the second-stage subsystem, ensuring a smooth transition with the first-stage subsystem and together forming a continuous and broad low-stiffness plateau region.

[0021] Preferably, both the first-stage buckling beam 20 and the second-stage buckling beam 40 are elastic beams with specific geometric configurations, including a smooth cosine-curved beam structure 220 and a circular arc beam structure 210; as in this application... Figure 3 As shown, the cosine curved beam structure 220 is longer than the circular arc beam structure 210. The cosine curved beam structure 220 in the first-stage buckling beam 20 is fixedly connected to the upper support seat 10, and the circular arc beam structure 210 in the first-stage buckling beam 20 is fixedly connected to the top of the connecting seat 30. The cosine curved beam structure 220 in the second-stage buckling beam 40 is fixedly connected to the connecting seat 30, and the circular arc beam structure 210 in the second-stage buckling beam 40 is fixedly connected to the top of the lower base 50.

[0022] Preferably, the upper support 10, connecting seat 30, and lower base 50 are rigid structures used to constrain the lateral displacement range of the ends of the first-stage buckling beam 20 and the second-stage buckling beam 40. In this embodiment, the core functions of the upper support, connecting seat, and lower base, in addition to connection, also include providing precise boundary constraints. Their "rigidity" means that within the working range of the vibration isolator, their own deformation is much smaller than the deformation of the buckling beam. They constrain the ends of the buckling beam through well-designed installation interfaces (this installation method belongs to conventional technical means such as grooves, slots, bolt holes, etc.), limiting the limit range of lateral displacement of the ends of the buckling beam, thereby controlling the instability deformation of the buckling beam within the scope of "controllable buckling" and preventing it from undergoing unlimited large-scale instability that may cause structural damage.

[0023] Preferably, both the first-stage buckling beam 20 and the second-stage buckling beam 40 are elastic beams; the "elasticity" of the elastic beam described in this application means that after undergoing repeated, large-amplitude bending deformation (buckling) within the design load range, the beam can completely recover its initial geometry without permanent plastic deformation when the load is removed. This characteristic is the basis for the long-term, stable operation of the vibration isolator. In terms of materials, various types of spring steel, high-performance alloy steel, titanium alloys, or specially treated elastic alloys are typically used.

[0024] Preferably, the profile curve of the cosine curved beam structure 220 is determined by a function. Where x and y are coordinates on the contour curve, this is a preferred and parameterizable implementation of the present invention. In the formula, the amplitude parameter 3 determines the maximum lateral offset of the beam, which directly affects the amplitude of the buckling mode and negative stiffness; the spatial frequency parameter (π / 20) determines the density of the waveform, which directly affects the axial equivalent stiffness and buckling trigger displacement of the beam.

[0025] Preferably, the circular arc beam structure 210 and the cosine curved beam structure 220 are integrally formed, and the cosine curved beam structure 220 and the circular arc beam structure 210 of the first-stage buckling beam 20 are respectively connected to the upper support seat 10 and the connecting seat 30; the cosine curved beam structure 220 and the circular arc beam structure 210 of the second-stage buckling beam 40 are respectively connected to the connecting seat 30 and the lower base 50.

[0026] Preferably, the buckling beam connection structure is made of spring steel.

[0027] Preferably, the multi-layer support assembly and the buckling beam connection structure are made of metallic materials. In this application, for the multi-layer support assembly (upper support, connecting support, lower base), high-strength aluminum alloy, structural steel, or stainless steel are typically selected to meet the high stiffness requirements. For the buckling beam connection structure (buckling beams at each level), special materials with excellent elasticity and fatigue properties need to be further selected from the metallic materials, such as various types of spring steel, beryllium copper alloy, precipitation hardening stainless steel, or titanium alloy.

[0028] Preferably, the present invention also relates to a method of using a multi-directional two-stage buckling beam quasi-zero stiffness vibration isolator, comprising the following steps: S1: When the upper support 10 is subjected to external pressure, it tends to displace downwards. At this time, the buckling beam 20 undergoes bending deformation under vertical pressure, and its internal stress gradually increases. When the critical buckling load is reached, the six buckling beams 20 begin to buckle and generate lateral displacement. The connecting seat 30 and the lower base 50 work together to limit the expansion range of this lateral displacement, so that the buckling beam 20 only undergoes controllable buckling deformation within a preset space, thereby consuming external excitation energy and achieving the first-level load-bearing and vibration reduction effect. S2: When the connecting seat 30 is subjected to the pressure of the first-level buckling 20, the upper support 10 and the connecting seat 30 tend to displace downwards. At this time, the buckling beam 40 undergoes bending deformation under vertical pressure, and its internal stress gradually increases. When the critical buckling load is reached, the eight buckling beams 40 begin to buckle and generate lateral displacement. The connecting seat 30 and the lower base 50 work together to limit the expansion range of this lateral displacement, so that the buckling beam 40 only undergoes controllable buckling deformation within a preset space, thereby consuming external excitation energy and achieving the second-level load-bearing and vibration reduction effect.

[0029] The above embodiments are merely preferred technical solutions of the present invention and should not be considered as limitations on the present invention. The scope of protection of the present invention should be limited to the technical solutions described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. A multi-directional two-stage buckling beam quasi-zero stiffness vibration isolator, characterized in that, The system includes a multi-layer support assembly, which has at least three layers, including an upper support (10), a connecting seat (30), and a lower base (50) from top to bottom. A buckling beam connection structure is provided between the multi-layer support assemblies. The buckling beam connection structure includes several first-level buckling beams (20), which are connected between the upper support (10) and the connecting seat (30) and are arranged in a ring along different directions to provide first-level load-bearing and quasi-zero stiffness effects. The buckling beam connection structure also includes several second-level buckling beams (40), which are connected between the connecting seat (30) and the lower base (50) and are arranged along different directions to provide second-level load-bearing and quasi-zero stiffness effects.

2. The multi-directional two-stage buckling beam quasi-zero stiffness vibration isolator according to claim 1, characterized in that: The number of first-stage buckling beams (20) is at least six, and the first-stage buckling beams (20) are evenly distributed around the central axis of the upper support (10) and the connecting seat (30).

3. The multi-directional two-stage buckling beam quasi-zero stiffness vibration isolator according to claim 1, characterized in that: The number of the second-stage buckling beams (40) is at least eight, and the second-stage buckling beams (40) are evenly distributed around the central axis of the connecting seat (30) and the lower base (50).

4. A multi-directional two-stage buckling beam quasi-zero stiffness vibration isolator according to claim 3, characterized in that: Both the first-stage buckling beam (20) and the second-stage buckling beam (40) are elastic beams with specific geometric configurations, which include a smooth cosine bending beam structure (220) and a circular arc beam structure (210).

5. A multi-directional two-stage buckling beam quasi-zero stiffness vibration isolator according to claim 1, characterized in that: The upper support (10), connecting seat (30) and lower base (50) are rigid structures used to constrain the lateral displacement range of the ends of the first-stage buckling beam (20) and the second-stage buckling beam (40).

6. A multi-directional two-stage buckling beam quasi-zero stiffness vibration isolator according to claim 5, characterized in that: Both the first-stage buckling beam (20) and the second-stage buckling beam (40) are elastic beams.

7. A multi-directional two-stage buckling beam quasi-zero stiffness vibration isolator according to claim 4, characterized in that: The circular arc beam structure (210) and the cosine curved beam structure (220) are integrally formed. The cosine curved beam structure (220) and the circular arc beam structure (210) of the first-stage buckling beam (20) are connected to the upper support seat (10) and the connecting seat (30) respectively. The cosine curved beam structure (220) and the circular arc beam structure (210) of the second-stage buckling beam (40) are connected to the connecting seat (30) and the lower base (50) respectively.

8. A multi-directional two-stage buckling beam quasi-zero stiffness vibration isolator according to claim 1, characterized in that: The buckling beam connection structure is made of spring steel.

9. A multi-directional two-stage buckling beam quasi-zero stiffness vibration isolator according to claim 1, characterized in that: The multi-layer support assembly is made of structural steel, stainless steel, or aluminum alloy.

10. The method of using the multi-directional two-stage buckling beam quasi-zero stiffness vibration isolator according to any one of claims 1-9, characterized in that, Includes the following steps: S1: When the upper support is subjected to external pressure, it tends to displace downwards. At this time, the buckling beam undergoes bending deformation under vertical pressure, and its internal stress gradually increases. When the critical buckling load is reached, six buckling beams begin to buckle and produce lateral displacement. The connecting seat and the lower base work together to limit the expansion range of this lateral displacement, so that the buckling beam undergoes controllable buckling deformation only within a preset space, thereby consuming external excitation energy and achieving the first-level load-bearing and vibration reduction effect. S2: When the connecting seat is subjected to the pressure of the first-level buckling, the upper support and the connecting seat tend to displace downwards. At this time, the buckling beam undergoes bending deformation under vertical pressure, and its internal stress gradually increases. When the critical buckling load is reached, eight buckling beams begin to buckle and produce lateral displacement. The connecting seat and the lower base work together to limit the expansion range of this lateral displacement, so that the buckling beam undergoes controllable buckling deformation only within a preset space, thereby consuming external excitation energy and achieving the second-level load-bearing and vibration reduction effect.

Images