Adjustable negative stiffness device and adjustment method for bearing-related friction force

Abstract

This invention provides a negative stiffness device and adjustment method with adjustable bearing-related friction force, relating to the technical field of negative stiffness energy dissipation and vibration reduction devices. It includes a self-balancing frame, a lever, and a preloaded spring structure. One end of the self-balancing frame is rotatably connected to one end of the preloaded spring structure via corresponding connectors and a bearing structure. The end of the lever facing away from the self-balancing frame is rotatably connected to the end of the preloaded spring structure facing away from the self-balancing frame via corresponding connectors and a bearing structure. The bearing structure includes a friction ring and a bearing body, with the friction ring detachably connected to the bearing body. The friction ring is used to rub against the bearing body, causing the bearing body to experience a related friction force during rotation. A friction ring with a suitable friction coefficient is selected using the proposed related friction force adjustment method. This invention alleviates the technical problem in the prior art where the performance of negative stiffness energy dissipation and vibration reduction devices is poor due to the mismatch in the magnitude of the related friction force within the negative stiffness device.

Description

Technical Field

[0001] This invention relates to the technical field of negative stiffness energy dissipation and vibration reduction devices, and in particular to a negative stiffness device and adjustment method with adjustable bearing-related friction force. Background Technology

[0002] Negative stiffness devices can generate forces in the same direction as structural displacement, thus assisting structural deformation. Therefore, the slope of their force-displacement curve is negative, hence the term "negative stiffness mechanism." When considering the connection support stiffness of the damper, connecting a negative stiffness device in parallel with the damper results in a larger displacement for the damper connected in parallel with the negative stiffness spring due to the characteristic of the negative stiffness mechanism promoting displacement development at both ends. This increases the hysteresis area of ​​the damper, achieving enhanced damping efficiency. This is the principle of negative stiffness damping efficiency enhancement.

[0003] The most common configuration for implementing negative stiffness mechanisms is the preloaded spring-lever type negative stiffness device. The working principle of the preloaded spring-lever type negative stiffness device is to utilize the elastic potential energy stored in the preloaded spring. During operation, the spring preload is released to provide thrust, and the output force is amplified by the lever mechanism, thereby improving the utilization efficiency of the spring preload.

[0004] However, existing lever-preloaded spring-type negative stiffness devices have the following problems: First, the force-displacement curves of lever-preloaded spring-type negative stiffness devices all exhibit obvious associated frictional hysteresis, meaning that the greater the output force of the lever-preloaded spring-type negative stiffness device, the greater the preload demand and the greater the friction between the bearing and the journal; Second, the existence of associated friction will negatively affect the performance of the lever-preloaded spring-type negative stiffness device, hindering the effect of the negative stiffness device in promoting the relative displacement development at both ends during the negative stiffness stage, thereby weakening the damping amplification effect of the negative stiffness device on the parallel damper. Moreover, associated friction has a certain hysteresis energy dissipation. If the influence of this additional hysteresis energy dissipation is not considered in the vibration reduction design, it will affect the overall vibration reduction effect of the negative stiffness energy dissipation vibration reduction device on the structure. Summary of the Invention

[0005] The purpose of this invention is to provide a negative stiffness device and adjustment method with adjustable bearing-related friction force, so as to alleviate the technical problem in the prior art that the performance of the negative stiffness energy dissipation and vibration reduction device is poor due to the mismatch of the magnitude of the related friction force inside the negative stiffness device.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a negative stiffness device with adjustable bearing-related friction force, comprising a self-balancing frame, a lever and a preloaded spring structure, wherein one end of the self-balancing frame is rotatably connected to one end of the lever via a corresponding connector and a bearing structure, and the other end of the self-balancing frame is rotatably connected to one end of the preloaded spring structure via a corresponding connector and a bearing structure. The end of the lever that is away from the self-balancing frame and the end of the pre-compression spring structure that is away from the self-balancing frame are rotatably connected by a corresponding connector and the bearing structure. The bearing structure includes a friction ring and a bearing body. The friction ring is detachably connected to the bearing body, and the friction ring is used to cause the bearing body to be subjected to an associated frictional force when rotating by rubbing against the bearing body.

[0007] Furthermore, the preloaded spring structure includes a left end plate assembly, a spring pad, a spring assembly, a guide tube, and a right end plate assembly. The left end plate assembly is connected to the self-balancing frame through corresponding connectors and the bearing structure, and the left end plate assembly is inserted into the right end plate assembly through the guide tube. The end of the right end plate assembly that is away from the left end plate assembly is connected to the self-balancing frame via a corresponding connector and the bearing structure. The spring assembly is connected to the left end plate assembly, and the spring assembly is located between the left end plate assembly and the right end plate assembly. The two ends of the spring assembly are respectively provided with corresponding spring pads.

[0008] Furthermore, the left end plate assembly includes a left ear plate, a left end plate, and an outer sleeve, with the left ear plate provided on one side of the left end plate and the outer sleeve provided on the other side of the left end plate; The left ear plate is connected to the lever via a corresponding connector and the bearing structure; The outer sleeve is connected to the right end plate assembly via the conduit.

[0009] Furthermore, the right end plate assembly includes a right ear plate, a right end plate, and an inner guide rod. The right ear plate is provided on one side of the right end plate, and the inner guide rod is provided on the other side of the right end plate. The right ear plate is connected to the self-balancing frame via corresponding connectors and the bearing structure; The inner guide rod is connected to the outer sleeve through the conduit.

[0010] Furthermore, the self-balancing frame has a portal frame structure, and one end of the self-balancing frame is provided with a first ear plate; The lever is provided in two sets, and one end of each set of levers is rotatably connected to the first ear plate through a second connector. The bearing structure is provided between the second connector, the lever, and the first ear plate.

[0011] Furthermore, the self-balancing frame has two second ear plates spaced apart side-by-side at one end opposite to the first ear plate; The two second ear plates are rotatably connected to the preloaded spring structure via the first connector, and the bearing structure is provided between the first connector, the preloaded spring structure, and the second ear plates.

[0012] Furthermore, the two sets of levers are connected by a third connector, and the third connector is rotatably connected to one end of the output rod so that the output rod is located between the two sets of levers.

[0013] Furthermore, both ends of the friction ring are folded outward by 90° to form a first end and a second end, respectively; One end of the bearing body is connected to the first end, and the other end is connected to the second end.

[0014] Furthermore, the bearing-associated frictional force adjustable negative stiffness device also includes a plurality of gaskets, which are disposed between adjacent bearing structures and connected to the corresponding first connector or second connector.

[0015] Secondly, the present invention provides a method for adjusting bearing-related friction force, comprising: The material of the friction ring will be selected and the coefficient of friction of the friction material will be determined. The maximum value of the associated friction force of the adjustable negative stiffness device for bearing associated friction force will be calculated. F fmax The maximum value of the associated friction force F fmax The calculation formula is: ; A controlled structural finite element model with negative stiffness spring elements, viscous damping elements, and friction elements is established, and... F fmax The friction element is introduced into the finite element model; The seismic responses of controlled structures with negative stiffness spring elements, viscous damped elements, and friction elements were calculated, as well as the seismic responses of controlled structures with negative stiffness spring elements and viscous damped elements, and the energy ratio E was obtained. d1 / E d2 E d1 For the first calculation case, E is related to the total energy dissipation of frictional force and viscous damping. d2 For the viscous damping energy dissipation in the second calculation case; Determine the energy ratio Ed1 / E d2 Is it greater than 1? Energy ratio E d1 / E d2 If the value is less than 1, the material of the friction ring needs to be replaced; Energy ratio E d1 / E d2 If the value is greater than 1, then the working efficiency coefficient γ of the adjustable negative stiffness device for bearing-related friction needs to be calculated. The formula for calculating the working efficiency coefficient γ is as follows: ; If the efficiency coefficient γ is less than 1, the material of the friction ring needs to be replaced.

[0016] The present invention can achieve the following beneficial effects: In a first aspect, the present invention provides a negative stiffness device with adjustable bearing-related friction force, comprising a self-balancing frame, a lever, and a preloaded spring structure. One end of the self-balancing frame is rotatably connected to one end of the lever via a corresponding connector and a bearing structure, and the other end of the self-balancing frame is rotatably connected to one end of the preloaded spring structure via a corresponding connector and a bearing structure. The end of the lever opposite to the self-balancing frame is rotatably connected to the end of the preloaded spring structure opposite to the self-balancing frame via a corresponding connector and a bearing structure. The bearing structure includes a friction ring and a bearing body, the friction ring being detachably connected to the bearing body, and the friction ring being used to cause the bearing body to be subjected to associated friction force during rotation by rubbing against the bearing body.

[0017] In this invention, the self-balancing frame can be a portal frame, and a lever and a preload spring structure are provided between the two columns of the self-balancing frame. Specifically, one end of the lever is rotatably connected to one end of the self-balancing frame, and the other end of the lever is rotatably connected to the preload spring structure; the other end of the preload spring structure is rotatably connected to the self-balancing frame, and a bearing structure is provided at the connection of the three. Each bearing structure is connected to the bearing body through a friction ring, and the appropriate associated friction force of the bearing can be adjusted by selecting the appropriate friction ring according to actual needs.

[0018] Compared with the prior art, the bearing-related friction force adjustable negative stiffness device provided by the present invention sets a corresponding number of bearing structures at the rotational connection of the self-balancing frame, lever and preload spring structure, and selects a friction ring with a corresponding friction coefficient according to the actual use requirements and the proposed related friction force adjustment method, so as to avoid the problem of mismatch of related friction force inside the negative stiffness device, and thus effectively avoid the technical problem of the adverse effect of related friction force on the negative stiffness energy dissipation and vibration reduction device.

[0019] In summary, the present invention at least alleviates the technical problem in the prior art where the performance of the negative stiffness energy dissipation and vibration reduction device is poor due to the mismatch of the associated frictional forces inside the negative stiffness device. Attached Figure Description

[0020] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 A top view of the negative stiffness device with adjustable bearing-related friction force provided in an embodiment of the present invention; Figure 2 A schematic front view of the negative stiffness device with adjustable bearing-related friction force provided in an embodiment of the present invention; Figure 3 An exploded view of the preload spring of the bearing-associated frictional adjustable negative stiffness device provided in an embodiment of the present invention; Figure 4 A top view of the self-balancing frame of the bearing-associated frictional force adjustable negative stiffness device provided in an embodiment of the present invention; Figure 5 for Figure 4 Schematic diagram of the AA section structure; Figure 6 for Figure 4 Schematic diagram of the BB section structure; Figure 7 A top view of the lever structure of the bearing-associated frictional adjustable negative stiffness device provided in an embodiment of the present invention; Figure 8 A schematic diagram of the main structure of the lever of the bearing-associated frictional adjustable negative stiffness device provided in an embodiment of the present invention; Figure 9 A side view of the lever structure of the bearing-associated frictional adjustable negative stiffness device provided in an embodiment of the present invention; Figure 10 A top view of the output rod of the bearing-associated frictional force adjustable negative stiffness device provided in an embodiment of the present invention; Figure 11 This is a front view schematic diagram of the output rod of the bearing-associated frictional adjustable negative stiffness device provided in an embodiment of the present invention; Figure 12 A side view of the output rod of the bearing-associated frictional force adjustable negative stiffness device provided in an embodiment of the present invention; Figure 13 A schematic diagram of the main structure of the left end of the preload spring of the bearing-associated frictional adjustable negative stiffness device provided in an embodiment of the present invention; Figure 14 A top view of the left end of the preload spring of the negative stiffness device with adjustable bearing-related friction force provided in an embodiment of the present invention; Figure 15 A side view of the left end of the preload spring of the negative stiffness device with adjustable bearing-related friction force provided in an embodiment of the present invention; Figure 16 A schematic front view of the right end of the preload spring of the negative stiffness device with adjustable bearing-related friction force provided in an embodiment of the present invention; Figure 17 A top view of the right end of the preload spring of the negative stiffness device with adjustable bearing-related friction force provided in an embodiment of the present invention; Figure 18 A side view of the right end of the preload spring of the negative stiffness device with adjustable bearing-related friction force provided in an embodiment of the present invention; Figure 19 This is a front view of the conduit portion of the bearing-associated frictional force adjustable negative stiffness device provided in an embodiment of the present invention. Figure 20 A side view of the conduit portion of the bearing-associated frictional force adjustable negative stiffness device provided in an embodiment of the present invention; Figure 21 A front view schematic diagram of the spring assembly of the bearing-associated frictional force adjustable negative stiffness device provided in an embodiment of the present invention; Figure 22 A side view of the spring assembly of the bearing-associated frictional force adjustable negative stiffness device provided in an embodiment of the present invention; Figure 23 A schematic front view of the spring pad structure of the bearing-associated frictional force adjustable negative stiffness device provided in an embodiment of the present invention; Figure 24 A side view of the spring pad of the bearing-associated frictional force adjustable negative stiffness device provided in an embodiment of the present invention; Figure 25 A top view of the spring pad of the bearing-associated frictional force adjustable negative stiffness device provided in an embodiment of the present invention; Figure 26 A schematic diagram of the bearing structure of the bearing with adjustable negative stiffness device for bearing-related friction force provided in an embodiment of the present invention; Figure 27 for Figure 9 Schematic diagram of the AA section structure; Figure 28 A top view of the friction ring of the bearing-associated frictional force adjustable negative stiffness device provided in an embodiment of the present invention; Figure 29A cross-sectional view of the bearing-associated frictional force adjustable negative stiffness device provided in an embodiment of the present invention before the friction ring is locked; Figure 30 A cross-sectional view of the friction ring of the bearing-associated frictional force adjustable negative stiffness device provided in an embodiment of the present invention after locking. Figure 31 A schematic front view of the shim structure of the bearing-associated frictional force adjustable negative stiffness device provided in an embodiment of the present invention; Figure 32 A top view of the shim structure of the bearing-associated frictional force adjustable negative stiffness device provided in an embodiment of the present invention; Figure 33 Geometric diagram of the bearing-associated frictional force adjustable negative stiffness device provided in an embodiment of the present invention; Figure 34 A logic diagram of the bearing-related friction force adjustment method provided in an embodiment of the present invention.

[0022] Icons: 1-Self-balancing frame; 11-First ear plate; 12-Second ear plate; 13-First connector; 2-Lever; 21-Second connector; 22-Third connector; 3-Output rod; 4-Preload spring structure; 41-Left end plate assembly; 411-Left ear plate; 412-Left end plate; 413-Outer sleeve; 42-Spring pad; 43-Spring assembly; 44-Conduit; 45-Right end plate assembly; 451-Right ear plate; 452-Right end plate; 453-Inner guide rod; 5-Bearing structure; 51-Friction ring; 511-First end; 512-Second end; 52-Bearing body; 6-Washer. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and adjusted in various different configurations.

[0024] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0025] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0026] In the description of this invention, it should be noted that the terms "upper," "lower," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0027] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0028] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0029] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0030] Example 1 This embodiment provides a negative stiffness device with adjustable bearing-related friction force, referring to... Figure 1 and Figure 2 The adjustable negative stiffness device for bearing-related friction includes a self-balancing frame 1, a lever 2, and a preloaded spring structure 4. One end of the self-balancing frame 1 is rotatably connected to one end of the lever 2 via a corresponding connector and a bearing structure 5, and the other end of the self-balancing frame 1 is rotatably connected to one end of the preloaded spring structure 4 via a corresponding connector and a bearing structure 5. The end of the lever 2 away from the self-balancing frame 1 is rotatably connected to the end of the preloaded spring structure 4 away from the self-balancing frame 1 via a corresponding connector and a bearing structure 5. The bearing structure 5 includes a friction ring 51 and a bearing body 52. ​​The friction ring 51 is detachably connected to the bearing body 52, and the friction ring 51 is used to rub against the bearing body 52 so that the bearing body 52 is subjected to related friction force when rotating.

[0031] The embodiments of the present invention at least alleviate the technical problem in the prior art that the performance of negative stiffness energy dissipation and vibration reduction devices is poor due to the mismatch in the magnitude of the associated frictional forces inside the negative stiffness device.

[0032] In this embodiment of the invention, the self-balancing frame 1 can be a portal frame and can be made of channel steel. A lever 2 and a preloaded spring structure 4 are provided between the two columns of the self-balancing frame 1. Specifically, one end of the lever 2 is rotatably connected to one end of the self-balancing frame 1, and the other end of the lever 2 is rotatably connected to the preloaded spring structure 4. The other end of the preloaded spring structure 4 is rotatably connected to the self-balancing frame 1. A bearing structure 5 is provided at the connection of the three. Each bearing structure 5 is connected to a bearing body 52 by a friction ring 51. The appropriate friction force of the bearing can be adjusted by selecting the appropriate friction ring 51 according to actual needs.

[0033] Compared with the prior art, the bearing-related friction force adjustable negative stiffness device provided in this embodiment of the invention sets a corresponding number of bearing structures 5 at the rotational connection of the self-balancing frame 1, lever 2 and preloaded spring structure 4, and selects the corresponding friction ring 51 according to actual use requirements and the proposed related friction force adjustment method, so as to avoid the problem of mismatch in the magnitude of related friction force inside the negative stiffness device, thereby effectively avoiding the technical problem of related friction hysteresis affecting the performance of the negative stiffness energy dissipation and vibration reduction device.

[0034] In an optional implementation of this embodiment, refer to Figure 3 , Figure 19 , Figure 20 , Figure 21 , Figure 22 , Figure 23 , Figure 24 and Figure 25 The preloaded spring structure 4 includes a left end plate assembly 41, spring pads 42, a spring group 43, a conduit 44, and a right end plate assembly 45. The left end plate assembly 41 is connected to the self-balancing frame 1 through corresponding connectors and bearing structures 5, and the left end plate assembly 41 is inserted into the right end plate assembly 45 through the conduit 44. The end of the right end plate assembly 45 facing away from the left end plate assembly 41 is connected to the self-balancing frame 1 through corresponding connectors and bearing structures 5. The spring group 43 is connected to the left end plate assembly 41 and is located between the left end plate assembly 41 and the right end plate assembly 45. The two ends of the spring group 43 are respectively provided with corresponding spring pads 42.

[0035] Specifically: one end of the left end plate assembly 41 is rotatably connected to one end of the lever 2, while the other end of the left end plate assembly 41 passes through two sets of spring pads 42 and the spring assembly 43 between the two sets of spring pads 42 before being inserted into the right end plate assembly 45. A guide tube 44 is also provided between the left end plate assembly 41 and the right end plate assembly 45, and the other end of the right end plate assembly 45 is rotatably connected to the self-balancing frame 1. The ends of both the left end plate assembly 41 and the right end plate assembly 45 are connected to the lever 2 and the self-balancing frame 1 respectively through bearing structures 5. Specifically, the left end plate assembly 41 is rotatably connected to the second connecting member 21 through the bearing structure 5, and this second connecting member 21 is rotatably connected to the two levers 2 through two sets of bearing structures 5; correspondingly, the right end plate assembly 45 is rotatably connected to the first connecting member 13 through the bearing structure 5, and this first connecting member 13 is rotatably connected to the self-balancing frame 1 through two sets of bearing structures 5. The spring pads 42 have through holes, and the radius of the through holes is more than 5 mm larger than the outer diameter of the outer sleeve 413. The spring assembly 43 can be a disc spring. The guide tube 44 is a hollow cylinder, and its outer radius is the same as the inner diameter of the outer sleeve 413, and its inner radius is the same as the radius of the inner guide rod 453. The machining error is within ±0.3mm.

[0036] Furthermore, referring to Figure 13 , Figure 14 and Figure 15 The left end plate assembly 41 includes a left ear plate 411, a left end plate 412, and an outer sleeve 413. The left ear plate 411 is provided on one side of the left end plate 412, and the outer sleeve 413 is provided on the other side of the left end plate 412. The left ear plate 411 is connected to the lever 2 through a corresponding connector and bearing structure 5. The outer sleeve 413 is connected to the right end plate assembly 45 through a conduit 44.

[0037] Specifically: the left ear plate 411 has a through hole, and the left ear plate 411 is connected to the corresponding bearing structure 5 through this through hole, while the inner wall of the bearing structure 5 is connected to the corresponding second connecting member 21; the other end of the left end plate 412 is provided with an outer sleeve 413, which is connected to the right end plate assembly 45 through a conduit 44, and a spring assembly 43 and two sets of spring pads 42 are provided between the left end plate 412 and the right end plate assembly 45.

[0038] Furthermore, referring to Figure 16 , Figure 17 and Figure 18 The right end plate assembly 45 includes a right ear plate 451, a right end plate 452, and an inner guide rod 453. The right end plate 452 has a right ear plate 451 on one side and an inner guide rod 453 on the other side. The right ear plate 451 is connected to the self-balancing frame 1 through corresponding connectors and bearing structures 5. The inner guide rod 453 is connected to the outer sleeve 413 through a conduit 44.

[0039] Specifically: the right ear plate 451 has a through hole, through which it connects to the corresponding bearing structure 5, and the inner wall of the bearing structure 5 is connected to the corresponding first connecting member 13; the other end of the right end plate 452 has an inner guide rod 453, which connects to the outer sleeve 413 via a conduit 44; and a spring assembly 43 and two sets of spring pads 42 are provided between the left end plate 412 and the right end plate 452. The conduit 44 can be made of polytetrafluoroethylene. It should be noted that the holes in the left ear plate 411 and the right ear plate 451 need to be precision machined, and the machining error is within ±0.3mm.

[0040] In an optional implementation of this embodiment, refer to Figure 2 , Figure 4 , Figure 5 and Figure 6 The self-balancing frame 1 has a gate-shaped structure, and one end of the self-balancing frame 1 is provided with a first ear plate 11; the lever 2 is provided in two sets, and one end of each set of levers 2 is rotatably connected to the first ear plate 11 through the second connector 21, and a bearing structure 5 is provided between the second connector 21, the lever 2, and the first ear plate 11.

[0041] Specifically: A first ear plate 11 is provided on the inner wall of one end of the self-balancing frame 1, and a second ear plate 12 is provided on the inner wall of the other end of the self-balancing frame 1. The first ear plate 11 and the second ear plate 12 are distributed opposite to each other. Among them, a corresponding bearing structure 5 is provided in the circular hole of the first ear plate 11, and this bearing structure 5 is used to rotatably connect with the corresponding second connecting member 21, so as to realize the rotatable connection with one end of the lever 2 through the second connecting member 21.

[0042] Furthermore, referring to Figure 2 , Figure 4 , Figure 5 and Figure 6 Two second ear plates 12 are arranged side by side at intervals at one end of the self-balancing frame 1 away from the first ear plate 11; the two second ear plates 12 are rotatably connected to the preload spring structure 4 through the first connector 13, and a bearing structure 5 is provided between the first connector 13, the preload spring structure 4, and the second ear plates 12.

[0043] Specifically: the first ear plate 11 and the second ear plate 12 are distributed opposite to each other, and the second ear plate 12 is provided with a corresponding bearing structure 5, which is rotatably connected to the first connecting member 13, so as to realize the rotatable connection between the right ear plate 451 of the preloaded spring structure 4 through the first connecting member 13.

[0044] In an optional implementation of this embodiment, refer to Figure 2 , Figure 7 , Figure 8 , Figure 9 , Figure 10 , Figure 11 and Figure 12 The two sets of levers 2 are connected by a third connector 22, and the third connector 22 is rotatably connected to one end of the output rod 3 so that the output rod 3 is located between the two sets of levers 2.

[0045] Specifically: one end of the third connecting piece 22 passes through the two levers 2 and the output rod 3 in sequence, so that the output rod 3 can be rotatably connected to the two levers 2 through the third connecting piece 22. It should be noted that the third connecting piece 22, the second connecting piece 21, and the first connecting piece 13 are all bolt and nut connection structures. The lever 2 has a left hole, a middle hole, and a right hole. The left and right holes have circular holes with the same radius as the outer circle radius of the bearing structure 5, and they need to be precision machined, with a machining error within ±0.3mm. The middle hole is a circular hole with the same radius as the outer circle radius of the third connecting piece 22, and the machining error is within ±0.3mm. The shaft of the third connecting piece 22 has threads at the end and is equipped with a nut. The middle part of the third connecting piece 22 of the anti-reverse bolt is a smooth rod, and the rod cross-section radius is the same as the inner circle radius of the friction ring 51, with the error controlled within ±0.3mm.

[0046] The output rod 3 has two bolt holes, the left hole and the right hole. The radii of the two holes are the same as the outer radius of the third connector 22, and the machining error is within ±0.3mm.

[0047] In an optional implementation of this embodiment, refer to Figure 26 , Figure 27 , Figure 28 , Figure 29 and Figure 30 Both ends of the friction ring 51 are folded outward by 90° to form a first end 511 and a second end 512, respectively; one end of the bearing body 52 is connected to the first end 511 and the other end is connected to the second end 512.

[0048] Specifically, the two ends of the friction ring 51 are folded outward to form a first end 511 and a second end 512. The first end 511 and the second end 512 are preferably snap-fit ​​structures. After the snap-fit ​​is bent, it undergoes plastic deformation to maintain the bent state, thus fixing it to the bearing body 52 without lateral displacement. The coefficient of friction of the friction ring 51 is changed by altering the material of the specially designed friction ring 51. For example, if low friction is required, tetrafluoroethylene (PTFE) can be used; if high friction is required, copper can be used. If a coefficient of friction close to 0 is needed, a needle roller bearing can be used directly instead of a variable coefficient of friction bearing.

[0049] In an optional implementation of this embodiment, refer to Figure 2 , Figure 31 and Figure 32The negative stiffness device with adjustable bearing-related friction also includes multiple gaskets 6, which are disposed between adjacent bearing structures 5 and connected to the corresponding first connector 13 or second connector 21.

[0050] Specifically: the gasket 6 can be a polytetrafluoroethylene gasket, which is used to be placed between adjacent bearing structures 5, and the gasket 6 can also be connected to the corresponding first connector 13 or second connector 21. The inner radius of the gasket 6 is the same as the radius of the third connector 22, and it is placed between the lugs of all the connection nodes.

[0051] This embodiment provides a method for adjusting bearing-related friction force, referring to... Figure 33 and Figure 34 ,include: The material of friction ring 51 will be selected and the coefficient of friction of the friction material will be determined. The maximum value of the associated friction force of the adjustable negative stiffness device for bearing associated friction force will be calculated. F fmax The maximum value of the associated friction force F fmax The calculation formula is: Establish a controlled structural finite element model with negative stiffness spring elements, viscous damping elements, and friction elements, and then... F fmax Friction elements are introduced into the finite element model; the seismic response of the controlled structure with negative stiffness spring elements, viscous damping elements, and friction elements are calculated respectively, as well as the seismic response of the controlled structure with negative stiffness spring elements and viscous damping elements, and the energy ratio E is obtained. d1 / E d2 E d1 For the first calculation case, E is related to the total energy dissipation of frictional force and viscous damping. d2 For the viscous damping energy dissipation in the second calculation case; determine the energy ratio E. d1 / E d2 Is it greater than 1? Energy ratio E d1 / E d2 If the value is less than 1, the material of friction ring 51 needs to be replaced; energy ratio E d1 / E d2 If the value is greater than 1, then the working efficiency coefficient γ of the adjustable negative stiffness device for bearing-related friction needs to be calculated. The formula for calculating the working efficiency coefficient γ is as follows: If the efficiency coefficient γ is less than 1, the material of friction ring 51 needs to be replaced.

[0052] Specifically: The maximum associated frictional force of the negative stiffness device is as shown in Formula 1:

[0053] in, =1 -Lp / L , β=1+L 1 / L 2, ρ=f v r , f v The friction coefficient of the bearing friction ring material. r The journal radius of the third connector 22. k NS This represents the negative stiffness value of the negative stiffness device, and the displacement q of the negative stiffness device that needs to be extracted from the finite element results.

[0054] The efficiency coefficient of the adjustable friction lever-preloaded spring negative stiffness device is shown in Formula 2:

[0055] When calculating the bearing-related friction force, first select the material of the friction ring 51 and determine the friction coefficient of the friction material. Then, calculate the maximum value of the related friction force of the adjustable related friction force lever-preload spring negative stiffness device according to Formula 1. F fmax The damping structure can be simulated using finite element software capable of simulating negative stiffness springs. In this embodiment, ETABS, OPENSEES, or SAP2000 can be used. A controlled structural finite element model with negative stiffness spring elements, viscous damping elements, and friction elements is established, and... F fmax Friction elements are introduced into the finite element model. The seismic responses of the controlled structures with negative stiffness spring elements + viscous damping elements + friction elements and with negative stiffness spring elements + viscous damping elements are calculated respectively, and the energy ratio E is obtained. d1 / E d2 , when E d1 / E d2 If E is greater than 1, then the associated frictional force plays a positive role; when E... d1 / E d2 If E is less than 1, then the associated frictional force has a negative effect. d1 / E d2 If E is less than 1, the material of friction ring 51 should be reselected. d1 / E d2 If the value is greater than 1, then the working efficiency coefficient γ of the adjustable associated friction lever-preloaded spring negative stiffness device should be further determined. Calculating γ requires obtaining the negative stiffness spring displacement q from the finite element results and substituting it into Formula 2 to calculate γ. γ must be greater than 1; otherwise, the material of friction ring 51 should be reselected.

[0056] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. The above embodiments in this specification are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A negative stiffness device with adjustable bearing-related friction force, characterized in that, It includes a self-balancing frame (1), a lever (2) and a preloaded spring structure (4). One end of the self-balancing frame (1) is rotatably connected to one end of the lever (2) through a corresponding connector and a bearing structure (5), and the other end of the self-balancing frame (1) is rotatably connected to one end of the preloaded spring structure (4) through a corresponding connector and a bearing structure (5). The lever (2) is rotatably connected to the end of the self-balancing frame (1) away from the lever (2) and the end of the preloaded spring structure (4) away from the self-balancing frame (1) through a corresponding connector and the bearing structure (5). The bearing structure (5) includes a friction ring (51) and a bearing body (52), the friction ring (51) being detachably connected to the bearing body (52), and the friction ring (51) being used to cause the bearing body (52) to be subjected to associated frictional force when rotating by rubbing against the bearing body (52).

2. The bearing-associated frictional force adjustable negative stiffness device according to claim 1, characterized in that, The preloaded spring structure (4) includes a left end plate assembly (41), a spring pad (42), a spring group (43), a conduit (44), and a right end plate assembly (45). The left end plate assembly (41) is connected to the self-balancing frame (1) through a corresponding connector and the bearing structure (5), and the left end plate assembly (41) is inserted into the right end plate assembly (45) through the conduit (44). The right end plate assembly (45) is connected to the self-balancing frame (1) at the end opposite to the left end plate assembly (41) via a corresponding connector and the bearing structure (5); The spring assembly (43) is connected to the left end plate assembly (41). The spring assembly (43) is located between the left end plate assembly (41) and the right end plate assembly (45), and the two ends of the spring assembly (43) are respectively provided with the corresponding spring pads (42).

3. The bearing-associated frictional force adjustable negative stiffness device according to claim 2, characterized in that, The left end plate assembly (41) includes a left ear plate (411), a left end plate (412) and an outer sleeve (413). The left ear plate (411) is provided on one side of the left end plate (412), and the outer sleeve (413) is provided on the other side of the left end plate (412). The left ear plate (411) is connected to the lever (2) via a corresponding connector and the bearing structure (5); The outer sleeve (413) is connected to the right end plate assembly (45) via the conduit (44).

4. The negative stiffness device with adjustable bearing-related friction force according to claim 3, characterized in that, The right end plate assembly (45) includes a right ear plate (451), a right end plate (452) and an inner guide rod (453). The right ear plate (451) is provided on one side of the right end plate (452), and the inner guide rod (453) is provided on the other side of the right end plate (452). The right ear plate (451) is connected to the self-balancing frame (1) through a corresponding connector and the bearing structure (5); The inner guide rod (453) is connected to the outer sleeve (413) through the conduit (44).

5. The negative stiffness device with adjustable bearing-related friction force according to claim 1, characterized in that, The self-balancing frame (1) has a gate-shaped structure, and one end of the self-balancing frame (1) is provided with a first ear plate (11). The lever (2) is provided in two sets, and one end of each set of levers (2) is rotatably connected to the first ear plate (11) through the second connector (21), and the bearing structure (5) is provided between the second connector (21), the lever (2) and the first ear plate (11).

6. The negative stiffness device with adjustable bearing-related friction force according to claim 5, characterized in that, The self-balancing frame (1) has two second ear plates (12) spaced apart side by side at one end away from the first ear plate (11). The two second ear plates (12) are rotatably connected to the preload spring structure (4) through the first connector (13), and the bearing structure (5) is provided between the first connector (13), the preload spring structure (4), and the second ear plates (12).

7. The bearing-associated frictional force adjustable negative stiffness device according to claim 5, characterized in that, The two sets of levers (2) are connected by a third connector (22), and the third connector (22) is rotatably connected to one end of the output rod (3) so that the output rod (3) is located between the two sets of levers (2).

8. The negative stiffness device with adjustable bearing-related friction force according to claim 1, characterized in that, Both ends of the friction ring (51) are folded outward by 90° to form a first end (511) and a second end (512) respectively. One end of the bearing body (52) is connected to the first end (511), and the other end is connected to the second end (512).

9. The negative stiffness device with adjustable bearing-related friction force according to claim 6, characterized in that, The bearing-associated frictional adjustable negative stiffness device also includes a plurality of gaskets (6), which are disposed between adjacent bearing structures (5) and are connected to the corresponding first connector (13) or second connector (21).

10. A method for adjusting a negative stiffness device with adjustable bearing-related friction force, characterized in that, include: The material of the friction ring (51) will be selected and the coefficient of friction of the friction material will be determined. The maximum value of the associated friction force of the bearing-associated friction force adjustable negative stiffness device will be calculated. F fmax The maximum value of the associated friction force F fmax The calculation formula is ; A controlled structural finite element model with negative stiffness spring elements, viscous damping elements, and friction elements is established, and... F fmax The friction element is introduced into the finite element model; The seismic responses of controlled structures with negative stiffness spring elements, viscous damped elements, and friction elements were calculated, as well as the seismic responses of controlled structures with negative stiffness spring elements and viscous damped elements, and the energy ratio E was obtained. d1 / E d2 E d1 For the first calculation case, E is related to the total energy dissipation of frictional force and viscous damping. d2 For the viscous damping energy dissipation in the second calculation case; Determine the energy ratio E d1 / E d2 Is it greater than 1? Energy ratio E d1 / E d2 If the value is less than 1, the material of the friction ring (51) needs to be replaced; Energy ratio E d1 / E d2 If the value is greater than 1, then the working efficiency coefficient γ of the adjustable negative stiffness device for bearing-related friction needs to be calculated. The formula for calculating the working efficiency coefficient γ is as follows: ; If the efficiency coefficient γ is less than 1, the material of the friction ring (51) needs to be replaced.

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