CN116753258A - Ultralow frequency vibration damper with three-way negative stiffness characteristic - Google Patents

Abstract

The application discloses an ultralow frequency vibration damper with three-way negative stiffness characteristics, which comprises a guide piece, a sliding plate, a first mounting plate and a second mounting plate, wherein the sliding plate is arranged on the guide piece in a sliding way; the permanent magnet assembly further comprises a first permanent magnet, a second permanent magnet and a third permanent magnet; the elastic piece realizes positive rigidity of the vibration damper in the Z direction, the first permanent magnet, the second permanent magnet and the third permanent magnet realize negative rigidity of the vibration damper in the Z direction, and the compression bar realizes positive and negative rigidity of the vibration damper in the X direction and the Y direction; thus, the vibration damping device has three-way negative stiffness; by introducing the three-way negative rigidity, the natural frequency of the vibration damper can be effectively reduced, so that the vibration damper has the total rigidity close to zero, and the vibration damper has further improved vibration damping performance.

Description

Ultralow frequency vibration damper with three-way negative stiffness characteristic

Technical Field

The application relates to the technical field of damping devices, in particular to an ultralow frequency damping device with three-way negative stiffness characteristics.

Background

In general, in order to provide a damper with a high-quality damping effect, the damper is designed to reduce the setting of stiffness, thereby achieving a lower natural frequency of the system and improving the damping performance of the damper.

In the design thought of some high-performance vibration absorbers, a mechanism with negative rigidity is introduced into a vibration absorber system, so that the natural frequency of the vibration absorber can be effectively reduced, and even the effect of quasi-zero rigidity can be realized.

However, most of the current shock absorber products with positive rigidity in the market generally have negative rigidity only in the vertical direction (one direction) even if a negative rigidity mechanism is introduced, and cannot achieve three-way (vertical direction, front-back direction, left-right direction) negative rigidity.

Disclosure of Invention

The application aims to overcome the defects in the prior art and provide an ultralow frequency vibration damper with three-way negative stiffness characteristic.

In order to achieve the technical purpose, the application provides an ultralow frequency vibration damper with three-way negative stiffness characteristics, which comprises the following components: the guide piece is arranged in an extending way along the Z direction; the sliding plate is arranged on the guide piece in a sliding way; the first mounting plate and the second mounting plate are arranged at intervals along the Z direction, and the sliding plate is arranged between the first mounting plate and the second mounting plate; the compression bar is connected with the first mounting plate and the sliding plate; the damping piece is connected with the first mounting plate and the second mounting plate; an elastic piece connecting the sliding plate and the second mounting plate; the first permanent magnet is arranged on the sliding plate; the first permanent magnet is arranged between the second permanent magnet and the third permanent magnet, and can be attracted by the second permanent magnet and the third permanent magnet; the first permanent magnet has an equilibrium position, and when the first permanent magnet is in the equilibrium position, the resultant force applied to the first permanent magnet is 0.

Further, the ultralow frequency vibration damping device with the three-way negative stiffness characteristic further comprises: the first buffer piece is arranged between the first permanent magnet and the second permanent magnet; and the second buffer piece is arranged between the first permanent magnet and the third permanent magnet.

Further, the second permanent magnet is arranged on the second mounting plate, and the third permanent magnet is arranged between the first mounting plate and the second mounting plate; the ultralow frequency vibration damper with the three-way negative stiffness characteristic further comprises a third buffer piece, and the third buffer piece is arranged between the third permanent magnet and the first mounting plate.

Further, a limiting groove is formed in one side, facing the second mounting plate, of the first mounting plate, and at least part of the third buffer piece is located in the limiting groove.

Further, a threaded hole is formed in the second mounting plate, and a threaded section is formed in the guide piece; the guide member is threadably connected to the second mounting plate by a threaded section and a threaded bore.

Further, the ultralow frequency vibration damping device with the three-way negative stiffness characteristic comprises four guide pieces, wherein the four guide pieces are arranged along the cross direction; the skateboard includes: a first mounting portion in which the first permanent magnet is disposed; the four second installation parts are arranged on the outer side of the first installation part along the cross direction, and any second installation part is sleeved on one guide piece.

Further, the ultralow frequency vibration damping device with the three-way negative stiffness characteristic comprises: four compression bars, any second installation part is connected with one compression bar; and/or four damping members, any damping member being located between two adjacent second mounting portions; and/or four elastic pieces, wherein any one of the second mounting parts is connected with one elastic piece.

Further, the ultralow frequency vibration damping device with the three-way negative stiffness characteristic further comprises: the fixed sleeve is arranged on the second mounting plate, and the second permanent magnet is arranged in the fixed sleeve; the third permanent magnet is arranged in the threaded sleeve; wherein, screw sleeve's outer wall is equipped with the external screw thread, and fixed sleeve's inner wall is equipped with the internal screw thread, screw sleeve and fixed sleeve can threaded connection.

Further, a holding groove is formed in the side edge of the first mounting plate and/or the side edge of the sliding plate, and a movable sheet is arranged on the outer side of the holding groove; the movable sheet is tightly pressed on the holding groove, and the movable sheet can fasten the compression bar in the holding groove.

Further, the damping piece is a steel wire rope; the ultralow frequency vibration damper with the three-way negative stiffness characteristic further comprises at least one pair of clamping plates, wherein the pair of clamping plates is used for fixing one steel wire rope; one of the clamping plates is used for fixing one end of the steel wire rope to the first mounting plate, and the other clamping plate is used for fixing the other end of the steel wire rope to the second mounting plate.

The application provides an ultralow frequency vibration damper with three-way negative stiffness characteristic, which comprises a guide piece, a sliding plate, a first mounting plate and a second mounting plate, wherein the sliding plate is arranged on the guide piece in a sliding way; the permanent magnet assembly comprises a first permanent magnet, a second permanent magnet and a third permanent magnet, wherein the first permanent magnet is arranged between the second permanent magnet and the third permanent magnet, and the first permanent magnet can be attracted by the second permanent magnet and the third permanent magnet; the elastic piece realizes positive rigidity of the vibration damper in the Z direction, the first permanent magnet, the second permanent magnet and the third permanent magnet realize negative rigidity of the vibration damper in the Z direction, when the vibration damper works near a balance point, the acting force of the negative rigidity spring on a load is almost zero, and the bearing capacity of the system is determined by a linear positive rigidity spring; once the load is slightly vibrated away from the balance position due to the transmission of foundation vibration, the system has lower dynamic stiffness due to the negative stiffness characteristic of the negative stiffness spring, so that the vibration isolation performance of the system is improved; the negative stiffness permanent magnet also has magnetic force with negative stiffness characteristic based on non-contact magnetic force, overcomes the mechanical friction defect of the mechanical negative stiffness spring, and has the characteristics of compact structure, adjustable stiffness and the like; in addition, the compression bar realizes positive and negative rigidity of the vibration damper in the X direction and the Y direction; the damping piece realizes the damping of the vibration damper in the X direction, the Y direction and the Z direction; thus, the vibration damping device has three-way negative stiffness; by introducing the three-way negative rigidity, the natural frequency of the vibration damper can be effectively reduced, so that the vibration damper has the total rigidity close to zero, and the vibration damper has further improved vibration damping performance.

Drawings

FIG. 1 is a graph showing the stiffness of an elastic member according to the present application;

FIG. 2 is a graph showing the stiffness of a first permanent magnet according to the present application;

FIG. 3 is a graph showing the stiffness of a vibration damping device according to the present application;

fig. 4 is an inverted pendulum structure according to the present application;

FIG. 5 is a schematic structural diagram of an ultralow frequency vibration damper with three-way negative stiffness characteristics according to the present application;

FIG. 6 is a cross-sectional view of the ultra-low frequency vibration damping device of FIG. 5 having a three-way negative stiffness characteristic;

fig. 7 is a cross-sectional view of the ultralow frequency vibration damping device having the three-way negative stiffness characteristic of fig. 5 when it receives a horizontal force.

Detailed Description

In order that the above objects, features and advantages of the application will be readily understood, a more particular description of the application will be rendered by reference to the appended drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. The present application may be embodied in many other forms than described herein and similarly modified by those skilled in the art without departing from the spirit of the application, whereby the application is not limited to the specific embodiments disclosed below.

The application provides an ultralow frequency vibration damper with three-way negative stiffness characteristics, which comprises: a guide 11 extending in the Z direction; a slide plate 12 slidably provided on the guide 11; the first mounting plate 13 and the second mounting plate 14 are arranged at intervals along the Z direction, and the sliding plate 12 is arranged between the first mounting plate 13 and the second mounting plate 14; a compression bar 15 connecting the first mounting plate 13 with the slide plate 12; a damper 16 connecting the first mounting plate 13 and the second mounting plate 14; an elastic member 17 connecting the slide plate 12 and the second mounting plate 14; a first permanent magnet 1 disposed on the slide plate 12; the second permanent magnet 2 and the third permanent magnet 3, the second permanent magnet 2 and the third permanent magnet 3 are arranged at intervals along the Z direction, the first permanent magnet 1 is arranged between the second permanent magnet 2 and the third permanent magnet 3, and the first permanent magnet 1 can be attracted by the second permanent magnet 2 and the third permanent magnet 3.

Wherein the first permanent magnet 1 has an equilibrium position, and when the first permanent magnet 1 is in the equilibrium position, the resultant force applied to the first permanent magnet 1 is 0.

First, it should be explained that stiffness is the ability of a member to resist deformation, generally producing the same displacement, the greater the load that needs to be applied, the greater the stiffness of the member. In general, the greater the displacement, the greater the force that needs to be applied, is the positive stiffness; the greater the displacement, the less force that needs to be applied, and is the negative stiffness.

In the vibration damping device provided by the application, the elastic member 17 is used for realizing positive rigidity in the Z direction.

Referring to fig. 1 in combination, a positive stiffness curve of the spring 17 is illustrated; wherein, the abscissa represents the deformation amount of the elastic member 17, the ordinate represents the elastic force of the elastic member 17, and the slope of the oblique line represents the rigidity of the elastic member 17.

Specifically, when the vibration damping device receives a Z-directional force, a load is transmitted between the first mounting plate 13, the compression bar 15, the slide plate 12, the elastic member 17, and the second mounting plate 14; the elastic member 17 is capable of deforming against an external force or stress.

Meanwhile, in the vibration damper provided by the application, the magnetic system formed by the first permanent magnet 1, the second permanent magnet 2 and the third permanent magnet 3 is used for realizing negative rigidity in the Z direction.

Referring specifically to fig. 5 and 6, in the illustrated embodiment, the first permanent magnet 1, the second permanent magnet 2 and the third permanent magnet 3 are arranged along the Z direction, and the magnetic directions of the three permanent magnets are the same (in the case shown in fig. 6, the three permanent magnets are all set to have the S pole up and the N pole down), so that the first permanent magnet 1 disposed in the middle can attract the second permanent magnet 2 opposite to each other, and attract the third permanent magnet 3 opposite to each other.

At this time, when the vibration damping device receives a Z-directional force, a load is transmitted to the first permanent magnet 1 through the first mounting plate 13, the pressing rod 15, and the slide plate 12. During the force transmission, if the first permanent magnet 1 leaves the equilibrium position, the attractive force from the second permanent magnet 2 received by the first permanent magnet 1 will be greater than the attractive force from the third permanent magnet 3, or the attractive force from the third permanent magnet 3 received by the first permanent magnet 1 will be greater than the attractive force from the second permanent magnet 2; thereby, the first permanent magnet 1 will exhibit a negative stiffness characteristic, such that the system has a lower dynamic stiffness.

Referring to fig. 2 in combination, a negative stiffness curve of a first permanent magnet 1 is illustrated; the abscissa is the displacement of the first permanent magnet 1, the ordinate is the resultant force applied to the first permanent magnet 1, and the slope of the curve is the magnetic negative stiffness of the first permanent magnet 1.

It is added that the guide 11 serves to define the direction of movement of the slide plate 12, and that the slide plate 12 can only move along the guide 11 in the Z-direction when force is transmitted to the slide plate 12, i.e. such that the movement of the first permanent magnet 1 exhibits a negative stiffness characteristic in the Z-direction but a positive stiffness characteristic in the X-direction and the Y-direction.

Referring to fig. 3 in combination, there is illustrated a stiffness curve of a vibration damping device provided by the present application (two dotted lines are the stiffness curves of the elastic member 17 and the first permanent magnet 1, respectively, and a solid line is the total stiffness curve of the vibration damping device); wherein, the abscissa is the displacement of the vibration damper, the ordinate is the resultant force applied to the vibration damper, and the slope of the solid line is the total rigidity of the vibration damper.

As can be seen from fig. 3, the stiffness of the damping device in the Z-direction can be reduced well by the mutual resistance or compensation of the positive and negative stiffness.

The vibration damper provided by the application realizes low dynamic stiffness near the working point by applying negative stiffness near the working position.

It is also necessary to supplement that the permanent magnet type negative stiffness is realized by adopting the first permanent magnet 1, the second permanent magnet 2 and the third permanent magnet 3, and though the stiffness nonlinear characteristic exists, the stiffness nonlinear is very weak and even negligible under the slight vibration by optimally designing the geometric parameters of the permanent magnets and reasonably selecting the distance between the permanent magnets, so that the permanent magnet type negative stiffness provided by the application can be processed linearly.

So that the negative stiffness is linear, and the vibration isolation system can be regarded as a linear system near the working point; in this way, the adverse effect of non-linear dynamics resulting from the low stiffness of the working point formed by the non-linear force displacement characteristics is avoided.

Further, since the negative stiffness permanent magnet has an unstable balance point, when the vibration damping device adopts a linear positive stiffness spring (such as the elastic piece 17) and the negative stiffness spring (such as a negative stiffness system formed by the first permanent magnet 1, the second permanent magnet 2 and the third permanent magnet 3) at the same time, the vibration damping device works near the balance point, the acting force of the negative stiffness spring to the load is almost zero, and the bearing capacity of the system is determined by the linear positive stiffness spring. Once the load is slightly vibrated away from the balance position due to the transmission of the foundation vibration, the negative stiffness characteristic of the negative stiffness spring can enable the system to have lower dynamic stiffness, so that the vibration isolation performance of the system is improved.

In addition, the negative-stiffness permanent magnet provided by the application has magnetic force with negative stiffness characteristic based on non-contact magnetic force, overcomes the mechanical friction defect of the mechanical negative-stiffness spring, and has the characteristics of compact structure, adjustable stiffness and the like.

In summary, the elastic member 17 and the magnetic system achieve positive and negative stiffness in the Z direction of the vibration damping device provided by the application.

In addition, in the vibration damping device provided by the application, the compression bar 15 is used for realizing positive and negative rigidity in the X direction and the Y direction.

Specifically, the pressing lever 15 is provided in an inverted pendulum structure. For convenience of explanation, referring first to fig. 4, a similar inverted pendulum structure is illustrated, in which one end of the swing link is fixedly disposed, and the other end is constrained by a load to remain horizontal (only to move in a horizontal plane) at all times. When the inverted pendulum is in a natural state without disturbance, the pendulum rod is in a stable state; once a disturbance level acts on the load, the load will produce a negative stiffness characteristic in the horizontal direction; under the condition of micro-amplitude vibration, according to the knowledge of engineering material mechanics, the expression of the horizontal total rigidity of the inverted pendulum is as follows:. It is known that the horizontal total stiffness expression of the inverted pendulum is composed of a positive stiffness portion and a negative stiffness portion. When the load mass exceeds a certain value, the inverted pendulum has negative rigidity characteristics, otherwise, the inverted pendulum is a positive rigidity system.

According to the application, the horizontal extremely low natural frequency can be realized by reasonably selecting the parameters of the swing rod and the load quality.

More specifically, in the vibration damping device provided by the present application, one end of the pressing rod 15 is connected to the slide plate 12, and the other end is connected to the first mounting plate 13, and since the slide plate 12 is restricted by the guide 11 and can be displaced only in the Z direction, the end of the pressing rod 15 connected to the slide plate 12 cannot be displaced in the X direction and the Y direction; and the other end of the pressing lever 15 connected to the first mounting plate 13 can be displaced in the X-direction and the Y-direction along with the first mounting plate 13.

Referring to fig. 5 to 7 in combination, in the illustrated embodiment, an external force acts on the first mounting plate 13, so that when the first mounting plate 13 is horizontally displaced relative to the second mounting plate 14, the other end of the compression bar 15 connected to the first mounting plate 13 is displaced, and the compression bar 15 is deformed; when the external force is removed, the compression bar 15 can be restored.

In the application, the compression bar 15 is arranged into an inverted pendulum structure, the compression bar 15 bears load force, and the Euler compression bar principle is utilized to realize negative rigidity characteristics, so that the compression bar is used as a horizontal negative rigidity system.

In summary, the positive and negative rigidity of the vibration damper provided by the application in the X direction and the Y direction is realized by the way of establishing the compression bar 15 with the first mounting plate 13 and the second mounting plate 14.

In the vibration damping device provided by the application, the damping piece 16 connected with the first mounting plate 13 and the second mounting plate 14 is used for realizing the damping of the vibration damping device in the X direction, the Y direction and the Z direction. The damping member 16 may be made of flexible material (such as rubber, plastic, etc.), elastic structures such as springs and elastic sheets, or hydraulic or pneumatic mechanisms. When the vibration damper is stressed to vibrate, the damping piece 16 can block the vibration and reduce the amplitude, so that the vibration damper is beneficial to vibration damping effect and can ensure the structural stability of the vibration damper.

In summary, according to the vibration damper provided by the application, the negative rigidity in the Z direction can be realized through the permanent magnet system formed by the first permanent magnet 1, the second permanent magnet 2 and the third permanent magnet 3; negative rigidity in the X direction and the Y direction can be realized by the inverted pendulum structure constituted by the compression bars 15; thus, the vibration damping device has three-way negative stiffness; by introducing the three-way negative rigidity, the natural frequency of the vibration damper can be effectively reduced, so that the vibration damper has the total rigidity close to zero, and the vibration damper has further improved vibration damping performance.

The guide 11 may be a guide member such as a guide rod or a rail. The present application is not limited to the mounting position, specific configuration and specific number of the guide members 11.

In one embodiment, referring to fig. 5, the guide 11 is a guide post, where the guide post extends along the Z direction, and the guide post is fixedly disposed on the second mounting plate 14.

In order to facilitate the connection of the guide piece 11 and the second mounting plate 14, the second mounting plate 14 is provided with a threaded hole, and the guide piece 11 is provided with a threaded section; the guide 11 can be screwed to the second mounting plate 14 by means of a threaded section and a threaded bore.

Referring to fig. 6 in combination, the end of the guide 11 has a thread; when the guide member 11 is mounted on the second mounting plate 14, the threaded section is screwed into the threaded hole, and the internal threads and the external threads are matched. Through setting up screw thread section and screw hole, both made things convenient for the installation of guide 11 (no longer need realize fixedly through steps such as welding) and made guide 11 possess detachable characteristic again to follow-up maintenance, the operation such as change of user.

Wherein the slide plate 12 is used for connecting the guide 11 and the first permanent magnet 3 so that the first permanent magnet 3 is located between the second permanent magnet 2 and the third permanent magnet 3 and is limited by the guide 11 to move only in the Z direction.

The application is not limited to the specific configuration of the slide plate 12. Wherein at least part of the slide plate 12 is arranged between the first mounting plate 13 and the second mounting plate 14 for facilitating the mounting of the compression bar 15 and the elastic member 17.

In some embodiments, the guide 11, the first permanent magnet 3, the second permanent magnet 2 and/or the third permanent magnet 3 are provided outside the first mounting plate 13 and the second mounting plate 14.

To protect the permanent magnet system, in another embodiment, the second permanent magnet 2 is arranged on the second mounting plate 14, and the first permanent magnet 3 and the third permanent magnet 3 are arranged between the first mounting plate 13 and the second mounting plate 14.

Referring specifically to fig. 5 and 6, in the illustrated embodiment, the other structures that make up the vibration damping device are located between the first mounting plate 13 and the second mounting plate 14. Thereby, the first mounting plate 13 and the second mounting plate 14 can protect other structures, and particularly, during the vibration reduction process, other structures can be prevented from interfering with the outside; meanwhile, each structure is tightly connected and mutually supported, which is beneficial to the structural stability and vibration reduction effect of the vibration reduction device.

The specific configuration and the specific number of the pressing lever 15, the damping member 16 and the elastic member 17 are also not limited to the present application.

In one embodiment, the compression bar 15 is made of a metal material; the damping piece 16 is a steel wire rope; the elastic member 17 is a spring.

In order to increase the structural stability of the vibration damping device, in one embodiment the vibration damping device comprises four guide elements 11, the four guide elements 11 being arranged in a cross-like direction. Meanwhile, the slide plate 12 includes: a first mounting portion 12a, the first permanent magnet 1 being provided in the first mounting portion 12 a; four second mounting portions 12b, the four second mounting portions 12b are arranged on the outer side of the first mounting portion 12a along the cross direction, and any one of the second mounting portions 12b is sleeved on one guide 11.

Referring specifically to fig. 5, in the illustrated embodiment, the sliding plate 12 has a cross-symmetrical structure, the first mounting portion 12a is located at the center of symmetry, and four second mounting portions 12b are equally spaced around the first mounting portion 12a, and any two adjacent second mounting portions 12b are perpendicular to each other; four guides 11 are also arranged at equal intervals around the first mounting portion 12 a.

With continued reference to fig. 5, the first mounting portion 12a is in the shape of a ring in which the first permanent magnet 1 is disposed; four second mounting portions 12b and four guides 11 are provided around the first permanent magnet 1. A guide hole is formed in any second mounting part 12b, and the second mounting part 12b is sleeved on the corresponding guide piece 11 through the guide hole; the four sets of guide systems (the guide 11 and the second mounting portion 12 b) cooperate to ensure the guide accuracy, and when an external force acts on the vibration damping device, the vibration damping performance can be improved by cooperation of multiple directions.

In order to improve the guiding precision, the vibration damping device also comprises a linear bearing; in the embodiment shown in fig. 6, a linear bearing is fixed in a guide hole by two retainers, and the slide plate 12 is slidably connected to the guide post by the linear bearing.

With continued reference to fig. 5 and 6, in the illustrated embodiment, the vibration damping device includes four struts 15, with either second mounting portion 12b being connected to one strut 15. One end of any one of the pressing rods 15 is connected to the second mounting portion 12b, and the other end is connected to the first mounting plate 13. The four compression bars 15 are matched, so that a more stable inverted pendulum structure can be formed; the four compression bars 15 are also able to jointly resist loads and adapt to deformations, contributing to the structural rigidity.

With continued reference to fig. 5 and 6, in the illustrated embodiment, the vibration damping device includes four damping members 16, with any damping member 16 being located between two adjacent second mounting portions 12 b. Therefore, gaps between the structures can be well utilized, and damping performance in all directions is guaranteed.

With continued reference to fig. 5 and 6, in the illustrated embodiment, the vibration damping device includes four elastic members 17, with either of the second mounting portions 12b being connected to one of the elastic members 17. The elastic member 17 can support the second mounting portion 12b to prevent the second mounting portion 12b from actively moving along the guide member 11; at the same time, the elastic member 17 provides a stable and reliable positive Z-direction stiffness for the vibration damper.

Further, in the embodiment shown in fig. 5, the elastic member 17 is sleeved on the guide member 11. At this time, the guide 11 can also define the deformation direction of the elastic member 17, ensuring that the elastic member 17 achieves elastic positive rigidity in the Z direction.

In order to facilitate the installation of the third permanent magnet 3, the vibration damping device further comprises a fixing sleeve 31, the fixing sleeve 31 is arranged on the second installation plate 14, and the second permanent magnet 2 and the third permanent magnet 3 are arranged in the fixing sleeve 31.

The second permanent magnet 2 may be fixed to the inner wall of the fixing sleeve 31 or to the second mounting plate 14. The positions of the second permanent magnet 2 and the third permanent magnet 3 in the Z direction are relatively fixed.

The fixing sleeve 31 can not only provide an installation position for the third permanent magnet 3, but also conceal and protect the three permanent magnets, and can also limit the movement direction of the first permanent magnet 1 to a certain extent.

In the embodiment shown in fig. 5, the fixing sleeve 31 is provided on the second mounting plate 14 between the four guides 11; four avoidance holes are formed in the fixing sleeve 31, and the Ren Yidi two mounting portions 12b extend out of one avoidance hole.

Further, the vibration damping device further comprises a threaded sleeve 32, and the third permanent magnet 3 is arranged in the threaded sleeve 32; the outer wall of the threaded sleeve 32 is provided with external threads, and the inner wall of the fixed sleeve 31 is provided with internal threads; the threaded sleeve 32 and the fixed sleeve 31 can be screwed by internal and external threads.

The third permanent magnet 3 can be quickly assembled and disassembled relative to the fixed sleeve 31 in a threaded connection mode; the distance between the second permanent magnet 2 and the third permanent magnet 3 can also be adjusted by adjusting the depth of the threaded connection, so that the rigidity is adjusted.

Optionally, the first permanent magnet 1 is glued to the slide plate 12.

Optionally, the second permanent magnet 2 is glued to the fixing sleeve 31 or the second mounting plate 14.

Optionally, the third permanent magnet 3 is glued in the fixed sleeve 31 or in the threaded sleeve 32.

Optionally, the vibration damping device provided by the application further comprises a first buffer piece 21 arranged between the first permanent magnet 1 and the second permanent magnet 2.

Optionally, the vibration damping device provided by the application further comprises a second buffer piece 22 arranged between the first permanent magnet 1 and the third permanent magnet 3.

Optionally, the vibration damping device provided by the application further comprises a third buffer member 23, wherein the third buffer member 23 is arranged between the third permanent magnet 3 and the first mounting plate 13.

Wherein the cushioning member (the first cushioning member 21, the second cushioning member 22 or the third cushioning member 23) is made of a flexible material such as rubber, plastic or the like. The buffer piece has certain elasticity and can be deformed under the stress.

By providing the buffer between the adjacent two permanent magnets, the adjacent two permanent magnets can be prevented from striking each other when they are close to each other. In some embodiments, the buffer member can also avoid the adjacent two permanent magnets from contacting each other, especially in special cases, can avoid the adjacent two permanent magnets from being closely adsorbed due to the excessive attraction force of each other, which is beneficial to the recovery and stable operation of the vibration damping device.

In the embodiment shown in fig. 6, the first buffer member 21 is provided on the side of the second permanent magnet 2 facing the first permanent magnet 1, and the first buffer member 21 is provided in a ring shape as a step wrapping the second permanent magnet 2. The second buffer member 22 is provided at a side of the third permanent magnet 3 facing the first permanent magnet 1, and the second buffer member 22 is provided in a ring shape as a step wrapping the third permanent magnet 3.

Optionally, the buffer is glued to the permanent magnet.

The buffer member is installed between the third permanent magnet 3 and the first mounting plate 13, so that the first mounting plate 13 can be prevented from striking the third permanent magnet 3, and the lower limit of the movement of the first mounting plate 13 in the Z direction can be limited, so that the first mounting plate 13 is prevented from being excessively close to the second mounting plate 14.

Referring to fig. 6, in the illustrated embodiment, the vibration damping device includes a fixed sleeve 31 and a threaded sleeve 32, and the third permanent magnet 3 and the third buffer 23 are both provided in the threaded sleeve 32; the third buffer member 23 is generally in a convex shape, the bottom large round table of the third buffer member 23 is arranged in the threaded sleeve 32, and the top small round table protrudes out of the threaded sleeve 32 and faces the first mounting plate 13.

Further, a limiting groove 13a is provided on a side of the first mounting plate 13 facing the second mounting plate 14, and at least part of the third buffer member 23 is located in the limiting groove 13 a.

With continued reference to fig. 6, in the illustrated embodiment, a cylindrical limiting groove 13a is provided on the lower surface of the first mounting plate 13; the third buffer piece 23 protrudes out of the small round platform of the threaded sleeve 32 and stretches into the limit groove 13a; as will be readily appreciated, the first mounting plate 13 will abut against the third buffer member 23 when approaching the second mounting plate 14 continuously in the Z direction, and the third buffer member 23 can hinder the approaching movement of the first mounting plate 13; when the first mounting plate 13 moves along the X direction and the Y direction, the groove wall of the limiting groove 13a contacts the third buffer member 23, and the third buffer member 23 can also prevent the horizontal movement of the first mounting plate 13; thereby, the arrangement of the limiting groove 13a and the third buffer 23 limits the movement range of the first mounting plate 13; the third damper 23 can also function to counteract vibrations by virtue of its flexible design.

Optionally, the first mounting plate 13 and the side edges of the sliding plate 12 are provided with holding grooves, and the outer sides of the holding grooves are provided with movable sheets 12c; the movable sheet 12c is pressed on the holding groove, and the movable sheet 12c can fasten the pressing rod 15 in the holding groove.

Referring to fig. 5, in the illustrated embodiment, four sides of the first mounting plate 13 are respectively provided with a holding groove, and an edge of each second mounting portion 12b is also provided with a holding groove. One end of the holding groove is opened so as to form a tablet 12c, and the other end of the holding groove is provided with a round hole for accommodating a cylindrical compression bar 15.

When the compression bar 15 is installed, the movable piece 12c is pulled outwards, so that the round hole is enlarged, and the compression bar 15 can extend into the round hole conveniently; after the compression bar 15 is in place, the flap 12c is pushed inward so that the flap 12c compresses the compression bar 15, thereby fixing the compression bar 15.

In order to ensure the fastening force of the movable plate 12c to the compression bar 15, in one embodiment, the groove wall of the holding groove and the movable plate 12c are provided with mounting holes, at least the mounting holes on the groove wall of the holding groove are threaded holes, so that the two mounting holes are opposite to each other, and screws are inserted into the two mounting holes, and the movable plate 12c can compress the compression bar 15 in the holding groove.

Or, the slot wall of the holding slot and the movable piece 12c are respectively provided with a slot and an insert block, so that the insert block is inserted into the slot, and the movable piece 12c and the holding slot can be fastened.

Or, the groove wall of the holding groove and the movable sheet 12c are respectively provided with a spring presser and a positioning hole; the spring presser is pressed so that the pin portion thereof is inserted into the positioning hole, thereby fastening the flap 12c and the holding groove.

The present application is not limited to the manner in which the flap 12c is fastened and moved relative to the holding groove.

In one embodiment, damping member 16 is a wire rope; in order to facilitate the installation of the steel wire rope, the damping device provided by the application further comprises at least one pair of clamping plates 32, wherein the pair of clamping plates 32 are used for fixing one steel wire rope;

one of the clamping plates 32 is used for fixing one end of the wire rope to the first mounting plate 13, and the other clamping plate 32 is used for fixing the other end of the wire rope to the second mounting plate 14.

Referring specifically to fig. 5, in the illustrated embodiment, a groove is formed on one side surface of the clamping plate 32 for accommodating the wire rope; the clamping plate 32 is provided with a penetrating mounting hole, and the first mounting plate 13 and the second mounting plate 14 are provided with threaded holes; so that the mounting holes on the clamping plate 32 are opposite to the threaded holes on the first mounting plate 13 or the second mounting plate 14, and bolts are used for fixing the clamping plate 32 on the first mounting plate 13 or the second mounting plate 14.

The foregoing examples illustrate only a few embodiments of the application, which are described in detail and are not to be construed as limiting the scope of the claims. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the application, which are all within the scope of the application. Accordingly, the scope of protection of the present application is to be determined by the appended claims.

Claims (10)

1. An ultralow frequency vibration damper with three-way negative stiffness characteristics, which is characterized by comprising:

a guide (11) extending in the Z direction;

a slide plate (12) slidably disposed on the guide member (11);

the sliding plate (12) is arranged between the first mounting plate (13) and the second mounting plate (14);

a compression bar (15) connecting the first mounting plate (13) with the slide plate (12);

a damper (16) connecting the first mounting plate (13) and the second mounting plate (14);

an elastic member (17) connecting the slide plate (12) and the second mounting plate (14);

a first permanent magnet (1) disposed on the slide plate (12);

the second permanent magnet (2) and the third permanent magnet (3), the second permanent magnet (2) and the third permanent magnet (3) are arranged at intervals along the Z direction, the first permanent magnet (1) is arranged between the second permanent magnet (2) and the third permanent magnet (3), and the first permanent magnet (1) can be attracted by the second permanent magnet (2) and the third permanent magnet (3);

wherein the first permanent magnet (1) has an equilibrium position, and when the first permanent magnet (1) is in the equilibrium position, the resultant force applied to the first permanent magnet (1) is 0.

2. The ultralow frequency vibration damping device having a three-way negative stiffness characteristic according to claim 1, further comprising:

a first buffer member (21) provided between the first permanent magnet (1) and the second permanent magnet (2);

and a second buffer member (22) arranged between the first permanent magnet (1) and the third permanent magnet (3).

3. The ultralow frequency vibration damping device with the three-way negative stiffness characteristic according to claim 1, characterized in that the second permanent magnet (2) is arranged on the second mounting plate (14), and the third permanent magnet (3) is arranged between the first mounting plate (13) and the second mounting plate (14);

the ultralow frequency vibration damper with the three-way negative stiffness characteristic further comprises a third buffer piece (23), and the third buffer piece (23) is arranged between the third permanent magnet (3) and the first mounting plate (13).

4. An ultralow frequency vibration-damping device with three-way negative stiffness characteristic according to claim 3, characterized in that the side of the first mounting plate (13) facing the second mounting plate (14) is provided with a limit groove (13 a), at least part of the third buffer member (23) being in the limit groove (13 a).

5. The ultralow frequency vibration damper with the three-way negative stiffness characteristic according to claim 1, characterized in that a threaded hole is arranged on the second mounting plate (14), and a threaded section is arranged on the guide piece (11);

the guide (11) can be screwed to the second mounting plate (14) via the threaded section and the threaded bore.

6. The ultralow frequency vibration damping device with three-way negative stiffness characteristic according to claim 1, characterized in that it comprises four of the guides (11), the four guides (11) being arranged in a cross direction;

the slide plate (12) comprises:

a first mounting portion (12 a), the first permanent magnet (1) being provided in the first mounting portion (12 a);

the four second installation parts (12 b) are arranged on the outer sides of the first installation parts (12 a) along the cross direction, and any one of the second installation parts (12 b) is sleeved on one guide piece (11).

7. The ultralow frequency vibration damping device having a three-way negative stiffness characteristic according to claim 6, characterized in that the ultralow frequency vibration damping device having a three-way negative stiffness characteristic comprises:

four compression bars (15), any one of the second installation parts (12 b) is connected with one compression bar (15);

and/or four said damping members (16), any one of said damping members (16) being located between two adjacent said second mounting portions (12 b);

and/or four elastic members (17), any one of the second mounting portions (12 b) being connected to one of the elastic members (17).

8. The ultralow frequency vibration damping device with three-way negative stiffness characteristic according to claim 1, characterized in that the ultralow frequency vibration damping device with three-way negative stiffness characteristic further comprises:

a fixed sleeve (31) arranged on the second mounting plate (14), and the second permanent magnet (2) is arranged in the fixed sleeve (31);

a threaded sleeve (32), the third permanent magnet (3) being arranged in the threaded sleeve (32);

the outer wall of the threaded sleeve (32) is provided with external threads, the inner wall of the fixed sleeve (31) is provided with internal threads, and the threaded sleeve (32) and the fixed sleeve (31) can be in threaded connection.

9. The ultralow frequency vibration damper with the three-way negative stiffness characteristic according to claim 1, wherein a holding groove is formed on the side edge of the first mounting plate (13) and/or the sliding plate (12), and a movable sheet (12 c) is arranged on the outer side of the holding groove;

the movable piece (12 c) is pressed on the holding groove, and the movable piece (12 c) can fasten the pressing rod (15) in the holding groove.

10. The ultralow frequency vibration damping device with three-way negative stiffness characteristic according to claim 1, characterized in that the damping member (16) is a wire rope;

the ultralow frequency vibration damper with the three-way negative stiffness characteristic further comprises at least one pair of clamping plates (32), wherein the clamping plates (32) are used for fixing one steel wire rope;

one (32) of the clamping plates (32) is used for fixing one end of the steel wire rope to the first mounting plate (13), and the other (32) of the clamping plates is used for fixing the other end of the steel wire rope to the second mounting plate (14).