Quasi-zero stiffness component and compact annular low-frequency vibration isolation device using quasi-zero stiffness component

Abstract

The invention relates to a quasi-zero stiffness component and a compact annular low-frequency vibration isolation device using the same, and belongs to the field of vibration isolators. The quasi-zero stiffness component comprises a seat body, a connecting rod, a positive stiffness mechanism and a negative stiffness mechanism; a mounting cavity is formed in the inner side of the seat body; the connecting rod is arranged in the mounting cavity in a reciprocating motion mode in the first direction, and one end of the connecting rod extends to the outer side of the seat body to form a first connecting end; the positive stiffness mechanism is located in the mounting cavity and comprises a planar elastic piece, and the planar elastic piece is connected with the connecting rod and the inner side wall of the mounting cavity at the same time; the negative stiffness mechanism is located in the mounting cavity and comprises an inner magnetic ring and an outer magnetic ring, the axes of the inner magnetic ring and the outer magnetic ring coincide with the connecting rod, the inner magnetic ring is configured to be located on the inner side of the outer magnetic ring, the inner magnetic ring and the outer magnetic ring are magnetized in the axial direction, the magnetizing directions are the same, the inner magnetic ring fixedly sleeves the connecting rod, and the outer magnetic ring is fixedly embedded in the inner side wall of the mounting cavity. According to the invention, low-frequency vibration suppression in the circumferential direction is realized, and the installation requirements of narrow space and high integration level can be met.

Description

Technical Field

[0001] This invention relates to the field of vibration isolators, and particularly to a quasi-zero stiffness member and a compact circumferential low-frequency vibration isolation device using the same. Background Technology

[0002] Impacts and vibrations are inevitable during the operation of mechanical equipment. They can easily lead to structural fatigue and performance degradation, and may even cause the failure of precision components, seriously affecting the reliability of the equipment. As modern industry develops towards higher precision and higher reliability, the power devices such as motors and shaft systems of precision instruments, medical equipment, aerospace equipment, and underwater vehicles have placed more stringent requirements on vibration reduction and noise reduction. These devices not only face the core challenges of low-frequency vibration energy concentration, which can easily lead to structural resonance and a decline in acoustic stealth performance, but are also constrained by their large weight and compact installation space. Traditional linear vibration isolation devices can no longer meet their usage requirements because they cannot simultaneously achieve high load-bearing capacity and low initial vibration isolation frequency. Quasi-zero stiffness vibration isolators, with their unique characteristics of "high static stiffness supporting the load and low dynamic stiffness achieving low-frequency vibration isolation," provide an effective technical path to solve the aforementioned problems. They possess advantages such as large load-bearing capacity, low dynamic stiffness, no significant resonance phenomenon, and significantly better low-frequency vibration isolation performance than linear isolation systems, and have received widespread attention in the field of vibration reduction and noise reduction in recent years. With the gradual improvement of quasi-zero stiffness theory, related structural designs are constantly emerging. Based on the differences in the vibration direction of the isolated object, existing quasi-zero stiffness vibration isolators can mostly be divided into two categories: unidirectional and multidirectional. However, both types of structures have significant technical shortcomings. Unidirectional quasi-zero stiffness vibration isolators possess "high static and low dynamic" stiffness characteristics only in a single degree of freedom, with motion in other directions being completely constrained. However, in practical engineering applications, rotating machinery and other equipment are prone to vibration transmission in any circumferential direction due to factors such as imbalance and asymmetry. The vibration source is not limited to a single degree of freedom, which greatly reduces the vibration isolation effect of such vibration isolators. While multi-directional quasi-zero stiffness vibration isolators can cover the needs of multi-degree-of-freedom vibration suppression and to some extent overcome the limitation of unidirectional vibration isolators that can only cope with vibration in one direction, such vibration isolators require the installation of many quasi-zero stiffness functional components, and the corresponding overall structure occupies a large space. This makes them difficult to adapt to scenarios with compact installation space requirements, such as precision equipment and underwater vehicle power units, thus limiting their application in narrow spaces and highly integrated equipment.

[0003] Based on this, the present invention provides a quasi-zero stiffness component and a compact circumferential low-frequency vibration isolation device using the same. The vibration isolation device constructs a circumferential multi-directional vibration isolation structure based on a ring-distributed quasi-zero stiffness functional component, which can achieve uniform distribution and efficient attenuation of vibration energy in any circumferential direction, and can solve the problem of circumferential multi-degree-of-freedom vibration transmission in rotating machinery and other equipment. At the same time, through the miniaturization and compact design of the quasi-zero stiffness functional component, the volume of the overall structure of the vibration isolation device can be significantly reduced, making it suitable for use in narrow-space, highly integrated equipment such as precision instruments and power devices. Summary of the Invention

[0004] Based on this, the present invention provides a quasi-zero stiffness component, including a base, a connecting rod, a positive stiffness mechanism, and a negative stiffness mechanism; an installation cavity is formed inside the base; the connecting rod is reciprocally movably disposed in the installation cavity along a first direction, and one end of the connecting rod extends to the outside of the base to form a first connection end for connection with a load; the positive stiffness mechanism is located in the installation cavity and includes a planar elastic element, the plane of which is perpendicular to the first direction, and the planar elastic element is simultaneously connected to the connecting rod and the inner sidewall of the installation cavity; the negative stiffness mechanism is located in the installation cavity and includes an inner magnetic ring and an outer magnetic ring whose axes coincide with the connecting rod, and the inner magnetic ring is configured to be located inside the outer magnetic ring, both the inner and outer magnetic rings are magnetized along the axial direction and in the same direction, the inner magnetic ring is fixedly sleeved on the connecting rod, and the outer magnetic ring is fixedly embedded in the inner sidewall of the installation cavity.

[0005] Furthermore, a second connecting end is formed at the end of the seat that is opposite to the first connecting end.

[0006] Furthermore, a first mounting hole is provided in the second connecting end, the first mounting hole communicates with the mounting cavity, and the end of the connecting rod away from the first connecting end extends into the first mounting hole and is slidably connected to the first mounting hole through a linear bearing.

[0007] Furthermore, the mounting cavity has a closed structure, and the mounting cavity has a second mounting hole for the connecting rod to pass through. The connecting rod is slidably connected to the second mounting hole through a linear bearing.

[0008] Furthermore, the inner wall of the mounting cavity is provided with an annular mounting groove, the middle of the side wall of the annular mounting groove is recessed to form an annular embedding groove, the outer magnetic ring is fixedly embedded in the embedding groove, and the inner wall of the outer magnetic ring is flush with the side wall of the annular mounting groove to form a contact surface; the planar elastic element is a planar spiral spring, the inner end of the planar spiral spring is fixedly provided with a first connecting ring, and is fixedly sleeved on the connecting rod through the first connecting ring; the outer section of the planar spiral spring is fixedly provided with a second connecting ring, the second connecting ring extends into the annular mounting groove and fits against the contact surface; there is a gap between the second connecting ring and the axial ends of the annular mounting groove, and the gap is filled with a plurality of stacked annular gaskets.

[0009] Furthermore, the base is assembled from a first component and a second component, which are detachably connected to each other, and the interface between the first component and the second component passes through the embedding groove.

[0010] In addition, the present invention also provides a compact circumferential low-frequency vibration isolation device, which includes the aforementioned quasi-zero stiffness member.

[0011] Furthermore, the vibration isolation device includes an inner ring and an outer ring that are circular and coaxially arranged, and a plurality of quasi-zero stiffness members are connected between the inner ring and the outer ring; the end of the quasi-zero stiffness member opposite to the first connecting end forms a second connecting end that protrudes outward, the first connecting end and the second connecting end of the quasi-zero stiffness member are respectively pivotally connected to the inner ring and the outer ring, and the direction of the connecting rod of the quasi-zero stiffness member coincides with the radial direction of the inner ring.

[0012] Furthermore, the outer ring includes an inner part and an outer part arranged inside and outside, both of which are circular and coaxially arranged. A rubber pad is provided between the inner part and the outer part, and the rubber pad is fixedly connected to both the inner part and the outer part. The second connecting end of the quasi-zero stiffness member is hinged to the inner part.

[0013] Furthermore, the number of the quasi-zero stiffness components is even and not less than 4, and the quasi-zero stiffness components are evenly arranged around the axis of the inner ring.

[0014] The principles and effects of the present invention will be further explained below with reference to the above technical solutions and accompanying drawings: The positive stiffness mechanism in this invention innovatively employs a planar elastic element, such as a planar spiral spring, while existing quasi-zero stiffness components mostly use cylindrical helical springs as their positive stiffness element. Compared to traditional cylindrical helical springs, the planar elastic element of this invention can significantly compress the axial dimension while providing the same stiffness, significantly reducing the space occupied by the quasi-zero stiffness component in the first direction. This flattened and compact design can reduce the overall volume of the vibration isolation device, thereby enabling the vibration isolation device using this component to adapt to narrow and compact installation environments. Furthermore, the preload adjustment mechanism formed by the annular gasket allows the quasi-zero stiffness component to adapt to different load deviations, always operating within the optimal quasi-zero stiffness range.

[0015] Furthermore, the vibration isolation device of the present invention constructs a circumferential radial structure of an inner ring, a quasi-zero stiffness member, and an outer ring. When the inner ring vibrates in any radial direction, the vibration vector is geometrically decomposed into components of each quasi-zero stiffness member along its radial axis. Since the quasi-zero stiffness member is installed with a pivot structure at both ends, the quasi-zero stiffness member only bears axial tensile and compressive loads, thereby triggering the internal quasi-zero stiffness system to attenuate vibration. This layout not only achieves vibration suppression in the circumferential direction, but also utilizes the compact characteristics of the quasi-zero stiffness member to make the gap between the inner and outer rings, i.e., the radial thickness of the device, very small, adapting to the installation requirements of narrow spaces and high integration. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the quasi-zero stiffness component described in an embodiment of the present invention; Figure 2 This is a schematic cross-sectional view of the quasi-zero stiffness component described in an embodiment of the present invention; Figure 3 This is a schematic diagram of the compact circumferential low-frequency vibration isolation device according to an embodiment of the present invention; Figure 4 This is a schematic cross-sectional view of the compact circumferential low-frequency vibration isolation device described in an embodiment of the present invention.

[0017] 1-Base, 11-First split body, 111-First connecting seat, 12-Second split body, 121-Second connecting seat, 13-Second connecting end, 131-First mounting hole, 14-Linear bearing, 15-Mounting cavity, 2-Connecting rod, 21-First connecting end, 22-Limiting ring, 23-Nut, 31-Planar spiral spring, 32-Second connecting ring, 33-First connecting ring, 24-Annular washer, 41-Inner magnetic ring, 42-Outer magnet, 51-Outer ring, 511-Outer side, 512-Inner side, 5121-Second mounting seat, 513-Rubber pad, 52-Inner ring, 521-First mounting seat. Detailed Implementation

[0018] To facilitate understanding by those skilled in the art, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments: A quasi-zero stiffness member, such as Figure 1-2 The system includes a base 1, a connecting rod 2, a positive stiffness mechanism, and a negative stiffness mechanism. A mounting cavity 15 is formed inside the base 1. The connecting rod 2 is reciprocally movable within the mounting cavity 15 along a first direction, and one end of the connecting rod 2 extends to the outside of the base 1, forming a first connecting end 21 for connection with a load. The positive stiffness mechanism is located within the mounting cavity 15 and includes a planar elastic element. The plane of the planar elastic element is perpendicular to the first direction, and the planar elastic element... Simultaneously connected to the connecting rod 2 and the inner wall of the mounting cavity 15; the negative stiffness mechanism is located within the mounting cavity 15, including an inner magnetic ring 41 and an outer magnetic ring 42 whose axes coincide with those of the connecting rod 2, and the inner magnetic ring 41 is configured to be located inside the outer magnetic ring 42. Both the inner magnetic ring 41 and the outer magnetic ring 42 are magnetized along the axial direction and in the same direction. The inner magnetic ring 41 is fixedly sleeved on the connecting rod 2, and the outer magnetic ring 42 is fixedly embedded in the inner wall of the mounting cavity 15. Wherein, the inner magnetic ring 41 being located inside the outer magnetic ring 42 means that the inner magnetic ring 41 is at least partially located inside the outer magnetic ring 42. Thus, after the inner magnetic ring 41 and the outer magnetic ring 42 are offset from each other (the center planes in the axial direction do not coincide), a repulsive force is generated between them along the first direction.

[0019] In this invention, a quasi-zero stiffness component is installed on a vibration isolation device as a core mechanical unit to provide the vibration isolation device with efficient suppression capability for low-frequency and ultra-low-frequency vibrations. The first direction is the vibration isolation direction of the quasi-zero stiffness component.

[0020] In this system, both the positive stiffness mechanism and the negative stiffness mechanism of the quasi-zero stiffness component use the connecting rod 2 and the inner wall of the mounting cavity 15 as common connecting carriers, thus constructing a quasi-zero stiffness system with parallel positive and negative stiffness. Specifically, the positive stiffness mechanism provides linear support stiffness using a planar elastic element arranged perpendicular to the first direction, while the negative stiffness mechanism provides nonlinear negative stiffness through a specific axial positional cooperation using an inner magnetic ring 41 and an outer magnetic ring 42 arranged coaxially and with the same magnetization direction. Based on this, when the load vibrates along the first direction, the connecting rod 2 connected to the load will reciprocate under the drive. The positive stiffness mechanism and the negative stiffness mechanism respond synchronously: the planar elastic element undergoes elastic deformation as the connecting rod 2 moves, generating a restoring force that resists movement, i.e., the positive stiffness force. At the same time, the inner magnetic ring 41, which moves synchronously with the connecting rod 2, undergoes axial misalignment relative to the outer magnetic ring 42, generating a repulsive force along the direction of motion under the action of the magnetic field, i.e., the negative stiffness force. By reasonably matching the elastic parameters of the planar elastic element with the magnetic parameters of the inner and outer magnetic rings 42, the positive stiffness force and the negative stiffness force are approximately equal in magnitude and opposite in direction near the preset equilibrium position, thus canceling each other out. As a result, the quasi-zero stiffness component as a whole exhibits the quasi-zero stiffness characteristics of "high static stiffness and low dynamic stiffness", which can significantly reduce the natural frequency of the system, effectively block the transmission of vibration energy, and has excellent low-frequency and ultra-low-frequency vibration isolation effects.

[0021] In this invention, the positive stiffness mechanism innovatively adopts a planar elastic element, such as a planar spiral spring 31. In contrast, the positive stiffness elements of existing quasi-zero stiffness components are mostly cylindrical helical springs. Compared with traditional cylindrical helical springs, the planar elastic element of this invention can greatly compress the axial dimension while providing the same stiffness, significantly reducing the space occupied by the quasi-zero stiffness component in the first direction. This flattened and compact design can reduce the overall volume of the vibration isolation device, thereby enabling the vibration isolation device using this component to adapt to narrow and compact installation environments.

[0022] In one embodiment, the end of the base 1 opposite to the first connecting end 21 is formed with a second connecting end 13.

[0023] The mounting cavity 15 is located away from the first connecting end 21, and is partially protruding away from the first connecting end 21 to form a second connecting end 13 at the end of the base body 1. The setting of the second connecting end 13 enables the quasi-zero stiffness component to form a double-end connection structure. The second connecting end 13 is used to firmly install the base body 1 on the mounting foundation. Together with the connection between the first connecting end 21 and the load, a complete vibration transmission and load-bearing path is constructed, which can ensure that the quasi-zero stiffness component can stably play a low-frequency vibration isolation role in the vibration isolation device.

[0024] In one embodiment, a first mounting hole 131 is provided in the second connecting end 13, the first mounting hole 131 communicates with the mounting cavity 15, and the end of the connecting rod 2 away from the first connecting end 21 extends into the first mounting hole 131 and is slidably connected to the first mounting hole 131 through a linear bearing 14.

[0025] By installing a linear bearing 14 inside the second connecting end 13, the frictional resistance of the connecting rod 2 when it moves along the first direction is effectively reduced, avoiding jamming caused by mechanical friction and ensuring vibration isolation performance under minor vibrations. On the other hand, the linear bearing 14 can also guide the movement of the connecting rod 2, preventing it from radially shifting or tilting during dynamic processes, ensuring that the inner magnetic ring 41 and the outer magnetic ring 42 always maintain a high-precision coaxial state, thereby maintaining the stability of the negative stiffness characteristics.

[0026] Furthermore, by utilizing the internal space of the second connecting end 13 to accommodate the tail end of the connecting rod 2, the structural dead zone is further utilized, which can achieve the purpose of continuing to compress the axial dimension of the quasi-zero stiffness component. Correspondingly, the overall volume of the vibration isolation device using it can be further reduced.

[0027] In one embodiment, the mounting cavity 15 is a closed structure, and the mounting cavity 15 has a second mounting hole through which the connecting rod 2 passes. The connecting rod 2 is slidably connected to the second mounting hole through a linear bearing 14.

[0028] The enclosed mounting cavity 15 provides a dustproof and impurity-proof sealed environment for the internal precision positive and negative stiffness mechanisms, effectively preventing performance failures caused by iron filings or foreign object jamming, thereby extending the service life of the quasi-zero stiffness component. Simultaneously, the linear bearing 14 at the second mounting hole and the linear bearing 14 at the first mounting hole 131 form a double-point support structure, further improving the smoothness and alignment of the connecting rod 2's movement.

[0029] In one embodiment, the outer wall of the connecting rod 2 is also provided with two protruding limiting rings 22. These two limiting rings 22 are located on both sides of the connection between the planar elastic element and the connecting rod 2, and are used to abut against the linear bearing 14, thereby limiting the displacement distance of the connecting rod 2. This ensures that during the reciprocating movement of the connecting rod 2, the inner magnetic ring 41 will not be completely misaligned with the outer magnetic ring 42, and will always maintain partial overlap to maintain a stable axial repulsive force between them, i.e., negative stiffness force, and avoid failure of the quasi-zero stiffness system.

[0030] In one embodiment, the inner wall of the mounting cavity 15 is provided with an annular mounting groove, the middle of the side wall of the annular mounting groove is recessed to form an annular embedding groove, the outer magnetic ring 42 is fixedly embedded in the embedding groove, and the inner wall of the outer magnetic ring 42 is flush with the side wall of the annular mounting groove to form an abutment surface; the planar elastic element is a planar spiral spring 31, the inner end of the planar spiral spring 31 is fixedly provided with a first connecting ring 33, and is fixedly sleeved on the connecting rod 2 through the first connecting ring 33; the outer section of the planar spiral spring 31 is fixedly provided with a second connecting ring 32, the second connecting ring 32 extends into the annular mounting groove and fits against the abutment surface; there is a gap between the second connecting ring 32 and the two axial ends of the annular mounting groove, and the gap is filled with a plurality of stacked annular gaskets 24.

[0031] The annular mounting groove and the embedded groove are located in the same axial position and form a nested structure. The outer magnetic ring 42 is embedded in the embedded groove, which not only fixes it firmly, but also provides an installation reference for the planar spiral spring 31 by forming an abutment surface on its inner sidewall. This realizes the overlapping and reuse of the inner magnetic ring 41, the outer magnetic ring 42 and the planar spiral spring 31 in the axial space, which can further compress the axial dimension of the quasi-zero stiffness component and make the structure of the quasi-zero stiffness component more compact.

[0032] Furthermore, by using a planar spiral spring 31 in conjunction with an annular washer 24, the stiffness of the quasi-zero stiffness component can be adjusted. Specifically, by increasing or decreasing the number of annular 52-shaped washer 24 in the gap between the two sides of the second connecting ring 32, the axial position of the second connecting ring 32, i.e., the outer end of the planar spiral spring 31, in the annular mounting groove can be finely adjusted. This fine adjustment can change the preload state of the planar spiral spring 31, thereby achieving fine adjustment of the positive stiffness parameter, so as to match the optimal quasi-zero stiffness effect according to the vibration characteristics of different loads, and improve the versatility and adaptability of the component.

[0033] In one embodiment, the positive stiffness mechanism includes two planar spiral springs 31, with first connecting rings 33 on each spring sleeved at the middle position of the connecting rod 2. The middle position of the connecting rod 2 has an external thread forming a threaded segment. By fitting a nut 23 onto the threaded segment and abutting against the first connecting ring 33, the first connecting ring 33 can be fixedly installed on the connecting rod 2. An inner magnetic ring 41 is sleeved on the connecting rod 2 and abutted against by the two first connecting rings 33 on the connecting rod 2, thereby achieving a fixed connection between the inner magnetic ring 41 and the connecting rod 2. The inner magnetic ring 41 is located between the two first connecting rings 33. The inner magnetic ring 41 between the connecting rings 33 allows the two first connecting rings 33 to separate from each other. Correspondingly, it can increase the distance between the two planar spiral springs 31, thereby avoiding interference between the two planar spiral springs 31 during operation. It is worth noting that the dimensions of the first connecting ring 33 and the second connecting ring 32 connected to the planar spiral springs 31 need to match the dimensions of the inner magnetic ring 41 so that when the inner magnetic ring 41 is clamped between the two first connecting rings 33, the second connecting rings 32 of the two planar spiral springs 31 still abut against each other.

[0034] In this planar spiral spring 31, the inner and outer ends of the spiral arm are connected to the first connecting ring 33 and the second connecting ring 32, respectively. To ensure a smooth transition when the spiral arm of the planar spiral spring 31 connects to the first connecting ring 33 and the second connecting ring 32, and to reduce stress concentration at the spring ends, the planar spiral spring 31 is designed with an involute cross-section. The load-bearing capacity of this planar spiral spring 31 can be increased by increasing the cross-sectional area of ​​its spiral arm or by increasing the amount of material used in its spiral arm.

[0035] In one embodiment, the base 1 is assembled from a first part 11 and a second part 12, the first part 11 and the second part 12 being detachably connected to each other, and the interface between the first part 11 and the second part 12 passing through the embedding groove.

[0036] The split-type design of the base 1 facilitates the assembly of its internal embedded structure. Specifically, the interface between the first split 11 and the second split 12 is set at the position passing through the embedding groove. When the base 1 is disassembled, the embedding groove and the annular mounting groove will be separated, and the operator can easily insert the outer magnetic ring 42 and the planar spiral spring 31. It can be seen that the split-type base 1 structure not only ensures the compactness of the structure, but also takes into account the convenience of manufacturing, assembly and subsequent maintenance.

[0037] In one embodiment, a plurality of first connecting seats 111 are provided on the outer side wall of the first segment 11 near the edge of the second segment 12, and a second connecting seat 121 is provided on the outer side wall of the second segment 12 near the edge of the first segment 11, corresponding to the first connecting seats 111. Both the first connecting seats 111 and the second connecting seats 121 are provided with threaded holes and are detachably connected to each other by a bolt connection structure, thereby realizing the detachable connection of the first segment 11 and the second segment 12.

[0038] Furthermore, based on the compact characteristics and quasi-zero stiffness mechanical properties of the aforementioned quasi-zero stiffness components, this invention also provides a compact circumferential low-frequency vibration isolation device, such as... Figure 3-4 It includes the aforementioned quasi-zero stiffness components.

[0039] In this invention, the vibration isolation device utilizes the volume advantage and mechanical properties of the aforementioned quasi-zero stiffness component to suppress low-frequency circumferential multi-degree-of-freedom vibrations in scenarios such as precision instruments and power devices, while also being adaptable to their narrow space and highly integrated installation environments.

[0040] In one embodiment, the vibration isolation device includes an inner ring 52 and an outer ring 51 that are circular and coaxially arranged, and a plurality of quasi-zero stiffness members are connected between the inner ring 52 and the outer ring 51; the end of the quasi-zero stiffness member opposite to the first connecting end 21 forms a second connecting end 13 that protrudes outward, the first connecting end 21 and the second connecting end 13 of the quasi-zero stiffness member are respectively pivotally connected to the inner ring 52 and the outer ring 51, and the direction of the connecting rod 2 of the quasi-zero stiffness member coincides with the radial direction of the inner ring 52.

[0041] The inner ring 52 is used to connect the vibration source, such as a power device. It can be connected to the vibration source through a sleeve connection structure, a bolt connection structure, etc. The outer ring 51 is used to install on the mounting base, such as on a frame. It can be installed through a bolt connection structure. This creates a circumferential radial structure of inner ring 52-quasi-zero stiffness component-outer ring 51. When the inner ring 52 vibrates in any radial direction, the vibration vector is geometrically decomposed into components of each quasi-zero stiffness component along its radial axis. Since the quasi-zero stiffness component is installed with a pivot structure at both ends, the quasi-zero stiffness component only bears axial tensile and compressive loads, which can trigger the internal quasi-zero stiffness system to attenuate vibration. This layout not only achieves vibration suppression in the circumferential direction, but also utilizes the compact characteristics of the quasi-zero stiffness component to make the gap between the inner ring 52 and the outer ring 51, i.e., the radial thickness of the device, very small, which is suitable for installation requirements with narrow space and high integration.

[0042] In one embodiment, the outer ring 51 includes an inner portion 512 and an outer portion 511 disposed inside and outside the outer ring. The inner portion 512 and the outer portion 511 are both annular and coaxially arranged. A rubber pad 513 is disposed between the inner portion 512 and the outer portion 511, and the rubber pad 513 is fixedly connected to both the inner portion 512 and the outer portion 511. The second connecting end 13 of the quasi-zero stiffness member is hinged to the inner portion 512.

[0043] The rubber pad 513, located between the inner side 512 and the outer side 511 of the outer ring 51, utilizes its material elasticity to provide high-frequency vibration isolation capability for the vibration isolation device, compensating for the attenuation of the vibration isolation effect of the quasi-zero stiffness component in the high-frequency range. Furthermore, the flexibility of the rubber layer can compensate for the machining and assembly tolerances and installation stresses between the inner ring 52 and the outer ring 51, improving the overall robustness of the device.

[0044] The working process of the vibration isolation device is as follows: When the vibration isolation equipment is running, it generates circumferential multidimensional vibration. The vibration wave is first transmitted to the inner ring 52. The vibration of the inner ring 52 drives the first connecting end 21 of each quasi-zero stiffness component to move, causing the connecting rod 2 to move back and forth relative to the seat 1. At this time, the planar spiral spring 31 inside the quasi-zero stiffness component works in conjunction with the magnetic negative stiffness mechanism, exhibiting extremely low dynamic stiffness near the equilibrium position, cutting off most of the low-frequency vibration energy. Only a very small part is transmitted to the outer ring 51, while the residual vibration transmitted to the outer ring 51, especially the high-frequency harmonics, will be further absorbed and attenuated by the rubber pad layer 513, ultimately achieving the vibration isolation effect on the installation foundation.

[0045] In one embodiment, a first mounting base 521 is provided on the outer side wall of the inner ring 52 corresponding to the first connecting end 21. A first rivet rod is rotatably provided on the first mounting base 521. The first rivet rod is arranged along the axial direction of the inner ring 52 and is fixedly connected to the first connecting end 21, thereby realizing the pivot connection between the first connecting end 21 and the inner ring 52. A second mounting base 5121 is provided on the inner side wall of the outer ring 51 corresponding to the second connecting end 13. A second rivet rod is rotatably provided on the second mounting base 5121. The second rivet rod is arranged along the axial direction of the outer ring 51 and is fixedly connected to the second connecting end 13, thereby realizing the pivot connection between the second connecting end 13 and the outer ring 51.

[0046] In one embodiment, the number of quasi-zero stiffness members is even and not less than four, and the quasi-zero stiffness members are evenly arranged around the axis of the inner ring 52.

[0047] Among them, the quasi-zero stiffness components adopt an even number and a centrally symmetrical uniform layout. The symmetrically distributed quasi-zero stiffness components can cancel each other out the static preload and prevent the inner ring 52 from becoming statically eccentric. The redundant configuration of no less than 4 components can ensure that there are enough quasi-zero stiffness components to participate in the work regardless of the direction of vibration, thereby achieving uniform distribution and efficient attenuation of vibration energy, which can significantly improve the stability and load-bearing capacity of the system.

[0048] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A quasi-zero stiffness component, characterized in that, include: The base has an installation cavity formed on its inner side; A connecting rod is reciprocally disposed within the mounting cavity along a first direction, and one end of the connecting rod extends to the outside of the base body to form a first connecting end; A positive stiffness mechanism, located within the mounting cavity, includes a planar elastic element. The plane of the planar elastic element is perpendicular to the first direction, and the planar elastic element is simultaneously connected to the connecting rod and the inner sidewall of the mounting cavity. A negative stiffness mechanism, located within the mounting cavity, includes an inner magnetic ring and an outer magnetic ring whose axes coincide with the connecting rod. The inner magnetic ring is configured to be located inside the outer magnetic ring. Both the inner and outer magnetic rings are magnetized along the axial direction and in the same direction. The inner magnetic ring is fixedly sleeved on the connecting rod, and the outer magnetic ring is fixedly embedded in the inner wall of the mounting cavity.

2. The quasi-zero stiffness member according to claim 1, characterized in that, The end of the seat opposite to the first connecting end has a second connecting end.

3. The quasi-zero stiffness member according to claim 2, characterized in that, The second connecting end has a first mounting hole, which communicates with the mounting cavity. The end of the connecting rod away from the first connecting end extends into the first mounting hole and is slidably connected to the first mounting hole via a linear bearing.

4. The quasi-zero stiffness member according to claim 1 or 3, characterized in that, The mounting cavity is a closed structure, and the mounting cavity has a second mounting hole for the connecting rod to pass through. The connecting rod is slidably connected to the second mounting hole through a linear bearing.

5. The quasi-zero stiffness member according to claim 1, characterized in that, The inner wall of the mounting cavity is provided with an annular mounting groove. The middle part of the side wall of the annular mounting groove is recessed to form an annular embedding groove. The outer magnetic ring is fixedly embedded in the embedding groove, and the inner wall of the outer magnetic ring is flush with the side wall of the annular mounting groove to form a contact surface. The planar elastic element is a planar spiral spring. The inner end of the planar spiral spring is fixedly provided with a first connecting ring, and is fixedly sleeved on the connecting rod through the first connecting ring. The outer section of the planar spiral spring is fixedly provided with a second connecting ring. The second connecting ring extends into the annular mounting groove and fits against the contact surface. There is a gap between the second connecting ring and the two axial ends of the annular mounting groove. Each gap is filled with a plurality of stacked annular gaskets.

6. The quasi-zero stiffness member according to claim 5, characterized in that, The base is composed of a first part and a second part, which are detachably connected to each other, and the interface between the first part and the second part passes through the embedding groove.

7. A compact circumferential low-frequency vibration isolation device, characterized in that, Includes the quasi-zero stiffness member as described in any one of claims 1-6.

8. The compact circumferential low-frequency vibration isolation device according to claim 7, characterized in that, The vibration isolation device includes an inner ring and an outer ring that are circular and coaxially arranged. A plurality of quasi-zero stiffness members are connected between the inner ring and the outer ring. The end of the quasi-zero stiffness member opposite to the first connecting end forms a second connecting end that protrudes outward. The first connecting end and the second connecting end of the quasi-zero stiffness member are respectively pivotally connected to the inner ring and the outer ring, and the direction of the connecting rod of the quasi-zero stiffness member coincides with the radial direction of the inner ring.

9. The compact circumferential low-frequency vibration isolation device according to claim 8, characterized in that, The outer ring includes an inner part and an outer part, both of which are circular and coaxial. A rubber pad is provided between the inner part and the outer part, and the rubber pad is fixedly connected to both the inner part and the outer part. The second connecting end of the quasi-zero stiffness member is hinged to the inner part.

10. The compact circumferential low-frequency vibration isolation device according to claim 8 or 9, characterized in that, The number of quasi-zero stiffness components is even and not less than 4, and the quasi-zero stiffness components are evenly arranged around the axis of the inner ring.

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