Variable-stiffness variable-damping self-resetting viscous damper
By using a variable stiffness and variable damping self-resetting viscous damper, the problem of balancing comfort control and structural safety dynamic response controller is solved, achieving self-resetting after an earthquake, reducing engineering design complexity and construction costs, and avoiding residual deformation after an earthquake.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SOUTHEAST UNIV
- Filing Date
- 2026-01-22
- Publication Date
- 2026-04-28
AI Technical Summary
In existing building structure vibration control, the difference in output characteristics between comfort control dampers and structural safety dynamic response controllers makes it impossible to achieve both simultaneously, increasing the complexity of engineering design and construction costs. Furthermore, safety dynamic response controllers are prone to causing large residual deformations after earthquakes, making repair difficult and sometimes requiring demolition and reconstruction.
Design a variable stiffness variable damping self-resetting viscous damper. By combining a piston rod and a viscous damping mechanism with a self-resetting mechanism, the damping force can be adjusted according to the displacement of the building structure, taking into account both comfort control and structural safety dynamic response control, and self-resetting after an earthquake.
It reduced the complexity of engineering design and construction costs, avoided large residual deformation of building structures after earthquakes, and improved the overall vibration control effect.
Smart Images
Figure CN121932060A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of building structure technology and relates to a variable stiffness variable damping self-resetting viscous damper. Background Technology
[0002] Building structural vibration control uses active, passive, or hybrid control technologies to suppress the vibration response of a structure under environmental excitations such as earthquakes and wind loads, the operation of equipment such as elevators and fans, or human activities. It often includes comfort control and structural safety dynamic response control. Its core is to achieve the dissipation, transfer, or cancellation of vibration energy by optimizing structural design and deploying control devices such as dampers.
[0003] Currently, the dampers used in existing building structure vibration control for comfort control and structural safety dynamic response control are different. Comfort control dampers are mainly for small-amplitude vibrations in daily life, close to the human body's sensitive frequency, with the core goal of high sensitivity and precise vibration attenuation and reducing human discomfort. Structural safety dynamic response control dampers are mainly for large-amplitude, high-energy vibrations caused by extreme loads such as earthquakes and strong winds, with the core goal of dissipating vibration energy with large output and avoiding structural damage.
[0004] However, due to the significant differences in output characteristics between comfort control dampers and structural safety dynamic response control dampers, they cannot be used interchangeably. Each type of damper must be designed or selected separately for its own control requirements. This not only increases the complexity of engineering design and construction costs but may also cause interference between the two types of devices, affecting the overall vibration control effect. Furthermore, safety dynamic response control dampers are typically based on ductile seismic design, which can easily lead to significant residual deformation in building structures after an earthquake. This makes the repair of some buildings with large residual deformation difficult and costly, and may even render some buildings unrepairable, requiring demolition and reconstruction, resulting in a significant waste of resources. Summary of the Invention
[0005] The purpose of this invention is to provide a variable stiffness and variable damping self-resetting viscous damper that can balance comfort control and structural safety dynamic response control, reduce engineering design complexity and construction costs, and at the same time, can self-reset after an earthquake, avoiding large residual deformation of the building structure after an earthquake.
[0006] The objective of this invention can be achieved through the following technical solutions: A variable stiffness variable damping self-resetting viscous damper includes: Piston rod; The first viscous damping mechanism includes a first cylinder through which the piston rod passes, and a first piston that can move back and forth along the inner wall of the first cylinder. The first cylinder stores a viscous fluid. The first piston is connected to the piston rod, and a first damping hole is also provided on the first piston along the axial direction of the piston rod. The second viscous damping mechanism includes a second cylinder that is passed through by the piston rod and fixedly connected to the first cylinder, and a second piston that can move back and forth along the inner wall of the second cylinder. The second cylinder also stores viscous fluid. An annular groove is also provided on the inner wall of the middle region of the second cylinder. The length of the annular groove is greater than the length of the second piston. A second damping hole is provided on the second piston. A self-resetting mechanism is provided at the end of the second cylinder and connected to the piston rod, and is configured to reset the piston rod after it has moved.
[0007] Furthermore, the self-resetting mechanism includes: A first pressure plate, a second pressure plate, and a third pressure plate are arranged sequentially along the piston rod axis away from the second cylinder body. The piston rod also passes through the first pressure plate, the second pressure plate, and the third pressure plate in sequence and is slidably connected to them. A first drive nut and a second drive nut are detachably sleeved on the piston rod. The first drive nut can contact and abut against the first pressure plate from the outside, and the second drive nut can contact and abut against the second pressure plate from the outside. A first elastic element, sleeved on the piston rod, passes through the second pressure plate and is located between the first pressure plate and the third pressure plate; A second elastic element is fitted onto the first elastic element and located between the second pressure plate and the third pressure plate; And a third elastic element fitted on the first elastic element and located between the first pressure plate and the second pressure plate.
[0008] Furthermore, under normal conditions, both the first and second elastic elements are preloaded, while the third elastic element may or may not be preloaded. Additionally, when the third elastic element is not preloaded and its length is less than the distance between the first and second pressure plates, the entire damper can achieve three-stage variable stiffness.
[0009] Furthermore, several through rods are evenly arranged around the piston rod between the second cylinder and the third pressure plate. One end of each through rod is fixedly connected to the second cylinder, and the other end passes through the first pressure plate, the second pressure plate, and the third pressure plate in sequence. A first limiting nut that can abut against the first pressure plate is also threaded on the side of the through rod near the second cylinder, and a second limiting nut that can abut against the third pressure plate from the outside is also threaded on the other end away from the first cylinder.
[0010] More preferably, the piston rod is provided with a first connector at the end near the first cylinder, and the through rod is provided with a second connector at the end near the third pressure plate. The first connector and the second connector are configured to connect to the building structure.
[0011] Furthermore, several first limiting screws are evenly arranged around the through rod between the second and third pressure plates. One end of each first limiting screw passes through the second pressure plate and is then threaded to a third limiting nut, while the other end passes through the third pressure plate and is threaded to a fourth limiting nut.
[0012] Furthermore, a plurality of second limiting screws are provided between the first pressure plate and the second pressure plate. One end of the second limiting screw is fixedly connected to the second pressure plate, and the other end passes through the first pressure plate and is slidably connected to the first pressure plate. A fifth limiting nut is also threadedly connected to the second limiting screw at the position between the first pressure plate and the second pressure plate.
[0013] More preferably, the second piston is located in the middle of the annular groove under normal conditions, and the distance between the second piston and one end of the annular groove is the same as the distance between the first pressure plate and the fifth limiting nut.
[0014] More preferably, the maximum distance the first piston and the second piston can move is the same as the maximum compression of the first elastic element.
[0015] Furthermore, the ultimate compression of the second elastic element satisfies: d 2 = 1.2 × h × i i ×cos i d - d 1, d 1 =h × i e ×cos i d , in, d 1 represents the distance between the second piston and one end of the annular groove. h For the building's structural floor height, i e The limit value for the elastic displacement angle of the building structure. i d It is the angle between the damper and the building structure when they are arranged. i i The limit value for the plastic displacement angle of the building structure. d 2 represents the ultimate compression of the second elastic element.
[0016] Furthermore, the viscous fluid is silicone oil.
[0017] Compared with the prior art, the present invention utilizes the viscous fluid flowing through multiple second damping holes and annular grooves on the second piston to provide a smaller viscous damping force. After the second piston contacts the inner wall of the second cylinder through the annular groove, the viscous fluid only flows through multiple second damping holes to provide a larger viscous damping force. Combined with the viscous damping force provided by the first viscous damping mechanism, the magnitude of the viscous damping force can be varied according to the magnitude of the building structure displacement, taking into account both comfort control and structural safety dynamic response control, reducing the complexity of engineering design and construction costs. At the same time, the self-resetting mechanism enables the building structure to self-reset after an earthquake, avoiding large residual deformation of the building structure after an earthquake. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of the overall structure of the present invention.
[0019] Figure 2 This is a schematic diagram of the main structure of the present invention.
[0020] Figure 3 This is a schematic diagram of the equilibrium position in this invention.
[0021] Figure 4 This is a schematic diagram of the structure subjected to small displacement and pressure in this invention.
[0022] Figure 5 This is a schematic diagram of the structure subjected to large displacement and compression in this invention.
[0023] Figure 6 This is a schematic diagram of the structure subjected to tension with small displacement in this invention.
[0024] Figure 7 This is a schematic diagram of the structure subjected to large displacement tension in this invention.
[0025] Explanation of markings in the diagram: 1. First connector, 2. Piston rod, 3. First viscous damping mechanism, 4. Second viscous damping mechanism, 5. Self-resetting mechanism, 6. Second connector, 7. First cylinder body, 8. First piston, 81. First damping hole, 9. First end cap, 10. Second end cap, 11. Second cylinder body, 111. Annular groove, 12. Second piston, 121. Second damping hole, 13. Third end cap, 14. Fourth end cap, 15. First bolt, 16. First elastic element, 1 7. Second elastic element; 18. Third elastic element; 19. First pressure plate; 20. Second pressure plate; 21. Third pressure plate; 22. First driving nut; 23. Second driving nut; 24. First limiting screw; 25. Second limiting screw; 26. Through rod; 27. First limiting nut; 28. Second limiting nut; 29. Third limiting nut; 30. Fourth limiting nut; 31. Fifth limiting nut; 32. First fixing nut; 33. Second fixing nut. Detailed Implementation
[0026] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.
[0027] In the description of this invention, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. The "and / or" in the text is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of this invention, "multiple" means two or more.
[0028] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for 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. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0029] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" 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.
[0030] Unless otherwise specified, the functional components or structures in the following embodiments or examples are conventional components or structures used in the art to achieve the corresponding functions.
[0031] To balance comfort control with structural safety and dynamic response control, this invention provides a variable stiffness, variable damping, self-resetting viscous damper. Please refer to [link to relevant documentation]. Figure 1 As shown, including: Piston rod 2; The first viscous damping mechanism 3 includes a first cylinder 7 through which the piston rod 2 passes, and a first piston 8 that can move back and forth along the inner wall of the first cylinder 7. The first cylinder 7 stores viscous fluid. The first piston 8 is connected to the piston rod 2. A first damping hole 81 is also provided on the first piston 8 along the axial direction of the piston rod 2. The second viscous damping mechanism 4 includes a second cylinder 11 through which the piston rod 2 passes and is fixedly connected to the first cylinder 7, and a second piston 12 that can move back and forth along the inner wall of the second cylinder 11. The second cylinder 11 also stores viscous fluid. The inner wall of the middle region of the second cylinder 11 is also provided with an annular groove 111. The length of the annular groove 111 is greater than the length of the second piston 12. The second piston 12 is provided with a second damping hole 121. A self-resetting mechanism is provided at the end of the second cylinder 11 and connected to the piston rod 2, and is configured to reset the piston rod 2 after it has moved.
[0032] In this invention, due to the arrangement of the annular groove 111, different damping forces based on the stroke of the second piston 12 can be constructed within the second viscous damping mechanism 4. For example, in a certain area of the annular groove 111, due to the gap between the second piston 12 and the second cylinder 11, the viscous damping force generated by the viscous fluid is small within the range of the second piston 12's movement stroke. In other areas, since the second piston 12 and the second cylinder 11 are in contact, the viscous fluid can only pass through the second damping hole 121, thereby generating a larger viscous damping force. In this way, a small viscous damping force is provided when the viscous fluid flows through the multiple second damping holes 121 and the annular groove 111 on the second piston 12. After the second piston 12 contacts the inner wall of the second cylinder 1111 through the annular groove 111, a larger viscous damping force is provided by the viscous fluid only passing through the multiple second damping holes 121. Combined with the viscous damping force provided by the first viscous damping mechanism 3, the magnitude of the viscous damping force can be changed according to the magnitude of the building structure displacement, taking into account both comfort control and structural safety dynamic response control, reducing the complexity of engineering design and construction costs. At the same time, the self-resetting mechanism enables the building structure to self-reset after the earthquake, avoiding large residual deformation of the building structure after the earthquake.
[0033] For some specific implementation methods, please refer to [link / reference]. Figure 2 As shown, the first cylinder 7 has open ends. A first end cap 9 and a second end cap 10 are fixedly installed at the two ends of the first cylinder 7. The piston rod 2 passes through the first end cap 9 and the second end cap 10 and is slidably sealed to the first end cap 9 and the second end cap 10 respectively. The second cylinder 11 can also be set as an open structure at both ends. A third end cap 13 and a fourth end cap 14 are fixedly installed at the two ends of the second cylinder 11. The piston rod 2 passes through the third end cap 13 and the fourth end cap 14 and is slidably sealed to the third end cap 13 and the fourth end cap 14 respectively. The second end cap 10 contacts the third end cap 13 and is fixed by a plurality of first bolts 15. The plurality of first bolts 15 are evenly arranged along the circumference of the second end cap 10.
[0034] For some specific implementation methods, please refer to [link / reference]. Figure 2 As shown in the figure, the self-resetting mechanism includes: A first pressure plate 19, a second pressure plate 20, and a third pressure plate 21 are arranged sequentially along the axial direction of the piston rod 2 away from the second cylinder 11. The piston rod 2 also passes through the first pressure plate 19, the second pressure plate 20, and the third pressure plate 21 in sequence and is slidably connected to them. A first drive nut 22 and a second drive nut 23 are detachably sleeved on the piston rod 2. The first drive nut 22 can contact and abut against the first pressure plate 19 from the outside, and the second drive nut 23 can contact and abut against the second pressure plate 20 from the outside. The first elastic element 16, which is sleeved on the piston rod 2, passes through the second pressure plate 20 and is located between the first pressure plate 19 and the third pressure plate 21; A second elastic element 17 is sleeved on the first elastic element 16 and located between the second pressure plate 20 and the third pressure plate 21; And a third elastic element 18 sleeved on the first elastic element 16 and located between the first pressure plate 19 and the second pressure plate 20.
[0035] Here, the first elastic element 16 and the second elastic element 17 can be ring springs, and the third elastic element 18 can be a cylindrical spring, which can provide stiffness and frictional energy dissipation during compression.
[0036] For more detailed implementation methods, please refer to [link / reference]. Figure 2 As shown, a plurality of through rods 26 are evenly arranged around the piston rod 2 between the second cylinder 11 and the third pressure plate 21. One end of each through rod 26 is fixedly connected to the second cylinder 11, and the other end passes sequentially through the first pressure plate 19, the second pressure plate 20, and the third pressure plate 21. A first limiting nut 27, which can abut against the first pressure plate 19, is threadedly connected to the side of the through rod 26 near the second cylinder 11, and a second limiting nut 28, which can abut against the third pressure plate 21 from the outside, is threadedly connected to the other end of the through rod 26 away from the first cylinder 11. The distance between the first pressure plate 19 and the third pressure plate 21 is adjusted by the first limiting nut 27 and the second limiting nut 28, which facilitates the application of preload to the first elastic element 16. More preferably, a first connector 1 is provided at the end of the piston rod 2 near the first cylinder 7, and a second connector 6 is provided at the end of the through rod 26 near the third pressure plate 21. The first connector 1 and the second connector 6 are configured to connect to the building structure.
[0037] For more detailed implementation methods, please refer to [link / reference]. Figure 2 As shown, a plurality of first limiting screws 24 are evenly arranged around the through rod 26 between the second pressure plate 20 and the third pressure plate 21. One end of each first limiting screw 24 passes through the second pressure plate 20 and is threaded to a third limiting nut 29, while the other end passes through the third pressure plate 21 and is threaded to a fourth limiting nut 30. The distance between the second pressure plate 20 and the third pressure plate 21 is adjusted by the third limiting nut 29 and the fourth limiting nut 30, which facilitates the application of preload to the second elastic element 17.
[0038] In a more specific embodiment, a plurality of second limiting screws 25 are provided between the first pressure plate 19 and the second pressure plate 20. One end of the second limiting screw 25 is fixedly connected to the second pressure plate 20, and the other end passes through the first pressure plate 19 and is slidably connected to the first pressure plate 19. The second limiting screw 25 is also threadedly connected to a fifth limiting nut 31 at a position between the first pressure plate 19 and the second pressure plate 20. The stiffness of the second elastic member 17 is greater than that of the third elastic member 18. The fifth limiting nut 31 ensures that when the first pressure plate 19 slides along the second limiting screw 25 to the fifth limiting nut 31, the third elastic member 18 will not be further compressed. In addition, the stiffness of the second elastic member 17 is greater than that of the third elastic member 18, so that the stiffness can change with the magnitude of the displacement of the building structure, further taking into account both comfort control and structural safety dynamic response control.
[0039] More preferably, in the normal state, the second piston 12 is located in the middle position of the annular groove 111, and the distance between the second piston 12 and one end of the annular groove 111 is the same as the distance between the first pressure plate 19 and the fifth limiting nut 31. This distance is calculated using the following formula: d 1 =h × i e ×cos i d , In the formula, d 1 represents the distance between the second piston 12 and one end of the annular groove 111. h For the building's structural floor height, i e The limit value for the elastic displacement angle of the building structure. i d It is the angle between the damper and the building structure when the damper is arranged.
[0040] More preferably, the maximum distance that the first piston 8 and the second piston 12 can move is the same as the maximum compression of the first elastic element 16, and this distance is calculated using the following formula: d =1.2× h × i i ×cos i d .
[0041] In the formula, d This represents the maximum distance that the first piston 88 and the second piston 1212 can move. i i This refers to the limit value of the plastic displacement angle of the building structure.
[0042] In a more specific embodiment, the ultimate compression of the second elastic element 17 satisfies: d 2 = 1.2 × h × i i ×cos i d - d 1, d 1 =h × i e ×cos i d , in, d 1 represents the distance between the second piston 12 and one end of the annular groove 111. h For the building's structural floor height, i e The limit value for the elastic displacement angle of the building structure. i d It is the angle between the damper and the building structure when they are arranged. i i The limit value for the plastic displacement angle of the building structure. d 2 represents the ultimate compression of the second elastic element 17.
[0043] In addition, in some other specific embodiments, the diameter of the piston rod 2 should meet the strength requirements: d rod ≥( n s 4 F / ps s ) 0.5 .
[0044] In the formula, d rod The diameter of piston rod 2 is... F For the maximum output of the damper, n s For safety margin, it is usually taken as 1.5 to 2.0. s s The yield strength of the piston rod 2 material; The diameter of piston rod 2 should meet the stability requirements: d rod ≥(64 F × n st ×( μL ) 2 / π 3 E ) 1 / 4 , In the formula, L This is the maximum extension length of piston rod 2.E It is the elastic modulus of the piston rod 2 material. n st This is the stability safety factor, typically taken as 2.5 to 4. m This is a length coefficient, usually taken as 1 to 2, which determines the final diameter of piston rod 2. d rod The larger of the strength index calculation result and the stability index calculation result should be taken and rounded up to the standard size. The diameter of the first piston 8 is calculated in the same way as the diameter of the second piston 12, using the following formula: D piston =(4 F viscous / πP max + d rod 2 ) 0.5 .
[0045] In the formula, D piston The diameter is either the diameter of the first piston 8 or the diameter of the second piston 12. F viscous This refers to the maximum output force of the first viscous damping mechanism 3 when there is no gap between the first cylinder 7 and the first piston 8, or the maximum output force of the second viscous damping mechanism 4 when there is no gap between the second cylinder 11 and the second piston 12. P max为 The maximum working pressure is usually taken as 15MPa~35MPa.
[0046] The wall thicknesses of the first cylinder block 77 and the second cylinder block 11 should satisfy the following formula: t ≥ D piston ×(([ s ] / ([ s ]-3 P max )) 0.5 -1) and t ≥ P max × D piston / [ s ].
[0047] In the formula, t The wall thickness of the first cylinder block 7 or the wall thickness of the second cylinder block 11, [ s ]= s s / n sWhen determining the wall thickness of the first cylinder 7 or the second cylinder 11, the larger of the calculation results of the two formulas above should be taken and rounded up to the standard size. The calculation method for the number and diameter of the first damping orifice 81 and the second damping orifice 121 is the same, both using the following formula: F viscous =(3 α +1 / αn hole ) α ·(( D piston 2 - d rod 2 ) / 4) α ·( d hole / 2) -(3α+1) · πv k L hole ·( D piston 2 - d rod 2 - n hole · d hole 2 ) · V α .
[0048] In the formula, n hole The number of the first damping orifice 81 or the number of the second damping orifice 121. d hole The diameter of the first damping orifice 81 or the diameter of the second damping orifice 121. α The damping exponent is typically taken as 0.2 to 1. v k The dynamic viscosity of silicone oil, L hole The length of the first damping orifice 81 or the length of the second damping orifice 121. V The damper experiences the maximum speed.
[0049] The diameter of the annular groove 111 is calculated using the following formula: F gap ={2 πv k L hole ·((D piston 2 - d rod 2 ) / 4)·[ π (( D gap 2 - d rod 2 ) / 4)] α} / {(2 πα / ( α +1))·[(2 α +2 / 2 α +1)·( D piston / 2)·( D gap - D piston / 4) 2+1 / α +( D gap - D piston / 4) 3+1 / α ·(11 α 2+12 α +3) / ((2 α +1)(3 α +1))]+ παn / (3α+1)·( d hole / 2) 3+1 / α} α · V α .
[0050] In the formula, D gap The diameter of the annular groove 111 F gap This is the maximum output force of the second viscous damping mechanism 4 when the second piston 12 is in the annular groove 111.
[0051] In a more specific embodiment, the viscous fluid is silicone oil.
[0052] Each of the above implementation methods can be implemented individually, or in any combination of two or more without violating logic.
[0053] The above implementation methods will be described in more detail below with reference to specific embodiments.
[0054] Example 1: like Figure 1 , Figure 2As shown, this invention provides a variable stiffness variable damping self-resetting viscous damper, including a piston rod 2, a first viscous damping mechanism 3, a second viscous damping mechanism 4, and a self-resetting mechanism 5. The first viscous damping mechanism 3 includes a first cylinder 7 and a first piston 8 inside it. The diameter of the first piston 8 is the same as the inner diameter of the first cylinder 7. One end of the piston rod 2 passes through both ends of the first cylinder 7 and is connected to the first piston 8 in sequence. The piston rod 2 and the first cylinder 7 are coaxially arranged and slidably sealed. The piston rod 2 and the first piston 8 are fixedly connected. A plurality of first damping holes 81 are opened on the first piston 8 along the axial direction of the piston rod 2. The plurality of first damping holes 81 are evenly arranged along the circumference of the first piston 8. The first cylinder 7 stores a viscous fluid, which provides viscous damping force for the movement of the first piston 8. The second viscous damping mechanism 4 includes a second cylinder 11 and a second piston 12 inside it. The diameter of the second piston 12 is the same as the inner diameter of the second cylinder 11. One end of the second cylinder 11... The piston rod 2 is fixedly connected to one end of the first cylinder 7. The end of the piston rod 2 passes through both ends of the second cylinder 11 and is connected to the second piston 12. The piston rod 2 and the second cylinder 11 are coaxially arranged and slidably sealed. The piston rod 2 and the second piston 12 are fixedly connected. An annular groove 111 is provided on the inner wall of the second cylinder 11 near the second piston 12. The length of the annular groove 111 is greater than the length of the second piston 12, and the diameter of the annular groove 111 is greater than the diameter of the second piston 12. Multiple second damping holes 121 are provided on the second piston 12 along the axial direction of the piston rod 2. The multiple second damping holes 121 are evenly arranged along the circumference of the second piston 12. The second cylinder 11 stores viscous fluid. By using the viscous fluid to pass through different positions of the second piston 12, different magnitudes of viscous damping force are provided. The self-resetting mechanism 5 is located at the end of the second cylinder 11 away from the first cylinder 7. The self-resetting mechanism 5 is connected to the piston rod 2 and is used to reset the piston rod 2 after it has moved. This invention utilizes the viscous fluid flowing through multiple second damping holes 121 and annular grooves 111 on the second piston 12 to provide a small viscous damping force. After the second piston 12 contacts the inner wall of the second cylinder 11 through the annular grooves 111, the viscous fluid only flows through multiple second damping holes 121 to provide a larger viscous damping force. Combined with the viscous damping force provided by the first viscous damping mechanism 3, the magnitude of the viscous damping force can be varied according to the magnitude of the building structure displacement, taking into account both comfort control and structural safety dynamic response control, reducing the complexity of engineering design and construction costs. At the same time, the self-resetting mechanism 5 enables the building structure to self-reset after an earthquake, avoiding large residual deformation of the building structure after an earthquake.
[0055] like Figure 2As shown, the first cylinder 7 has open ends, and a first end cap 9 and a second end cap 10 are fixedly installed at the two ends of the first cylinder 7. The piston rod 2 passes through the first end cap 9 and the second end cap 10 and is slidably sealed to the first end cap 9 and the second end cap 10 respectively. The second cylinder 11 has open ends, and a third end cap 13 and a fourth end cap 14 are fixedly installed at the two ends of the second cylinder 11. The piston rod 2 passes through the third end cap 13 and the fourth end cap 14 and is slidably sealed to the third end cap 13 and the fourth end cap 14 respectively. The second end cap 10 contacts the third end cap 13 and is fixed by a plurality of first bolts 15. The plurality of first bolts 15 are evenly arranged along the circumference of the second end cap 10.
[0056] like Figure 2 As shown, the self-resetting mechanism 5 includes a first pressure plate 19, a second pressure plate 20, a third pressure plate 21, a first drive nut 22, a second drive nut 23, a first elastic element 16, a second elastic element 17, and a third elastic element 18. The first pressure plate 19, the second pressure plate 20, and the third pressure plate 21 are arranged sequentially along the axial direction of the piston rod 2 and in a direction away from the second cylinder 11. The piston rod 2 passes through the first pressure plate 19, the second pressure plate 20, and the third pressure plate 21 in sequence and is slidably connected to the first pressure plate 19, the second pressure plate 20, and the third pressure plate 21, respectively. The first driving nut 22 and the second driving nut 23 are detachably sleeved on the piston rod 2. The first pressure plate 19, the second pressure plate 20, and the third pressure plate 21 are located between the first driving nut 22 and the second driving nut 23. The first driving nut 22 is in contact with the first pressure plate 19, and the second driving nut 23 is in contact with the third pressure plate 21. The first elastic element 16 is sleeved on the piston rod 2 and is located between the first pressure plate 19 and the third pressure plate 21. The first elastic element 16 passes through the second pressure plate 20 and is slidably connected to the second pressure plate 20. The second elastic element 17 is sleeved on the first elastic element 16 and is located between the second pressure plate 20 and the third pressure plate 21. The third elastic element 18 is sleeved on the first elastic element 16 and is located between the second pressure plate 20 and the first pressure plate 19. The first elastic element 16, the second elastic element 17, and the third elastic element 18 provide a restoring force for the displacement of the piston rod 2.
[0057] Among them, the first elastic element 16 and the second elastic element 17 are ring springs, and the third elastic element 18 is a cylindrical spring, which can provide stiffness and frictional energy dissipation during compression.
[0058] like Figure 2As shown, a plurality of through rods 26 are provided between the second cylinder 11 and the third pressure plate 21. The plurality of through rods 26 are evenly arranged around the piston rod 2. One end of each through rod 26 is fixedly connected to the second cylinder 11 by a second fixing nut 33. The other end of each through rod 26 passes through the first pressure plate 19, the second pressure plate 20 and the third pressure plate 21 in sequence. A first limiting nut 27 is threadedly connected to the side of the first pressure plate 19 near the second cylinder 11 on each through rod 26. A second limiting nut 28 is threadedly connected to the side of the third pressure plate 21 away from the second cylinder 11 on each through rod 26. The distance between the first pressure plate 19 and the third pressure plate 21 is adjusted by the first limiting nut 27 and the second limiting nut 28 to facilitate the application of preload to the first elastic element 16.
[0059] like Figure 2 As shown, a plurality of first limiting screws 24 are provided between the second pressure plate 20 and the third pressure plate 21. The plurality of first limiting screws 24 are evenly arranged around the plurality of through rods 26. One end of each first limiting screw 24 passes through the second pressure plate 20 and is threadedly connected to a third limiting nut 29. The other end of each first limiting screw 24 passes through the third pressure plate 21 and is threadedly connected to a fourth limiting nut 30. The distance between the second pressure plate 20 and the third pressure plate 21 is adjusted by the third limiting nut 29 and the fourth limiting nut 30, so as to facilitate the application of preload to the second elastic element 17.
[0060] like Figure 2 As shown, a plurality of second limiting screws 25 are provided between the first pressure plate 19 and the second pressure plate 20. The plurality of second limiting screws 25 are located between a plurality of first limiting screws 24 and are evenly arranged around the piston rod 2. One end of each second limiting screw 25 is fixedly connected to the second pressure plate 20 by a first fixing nut 32. The other end of each second limiting screw 25 passes through the first pressure plate 19 and is slidably connected to the first pressure plate 19. A fifth limiting nut 31 is threadedly connected to each second limiting screw 25 at a position between the first pressure plate 19 and the second pressure plate 20. The stiffness of the second elastic element 17 is greater than that of the third elastic element 18. The fifth limiting nut 31 ensures that when the first pressure plate 19 slides along the plurality of second limiting screws 25 to the fifth limiting nut 31, the third elastic element 18 will not be further compressed. In addition, the stiffness of the second elastic element 17 is greater than that of the third elastic element 18, so that the stiffness can change with the magnitude of the displacement of the building structure, further taking into account both comfort control and structural safety dynamic response control.
[0061] like Figure 2As shown, each second limiting screw 25 passes through the second pressure plate 20, and there are two corresponding first fixing nuts 32. The two first fixing nuts 32 are located on both sides of each second limiting screw 25 near the second pressure plate 20. Each second limiting screw 25 is fixed to the second pressure plate 20 by the two first fixing nuts 32. One end of each through rod 26 passes through the fourth end cover 14, and there are two corresponding second fixing nuts 33. The two second fixing nuts 33 are located on both sides of each through rod 26 near the fourth end cover 14. Each through rod 26 is fixed to the fourth end cover 14 by the two second fixing nuts 33.
[0062] like Figure 2 As shown, the piston rod 2 is provided with a first connector 1 at the end near the first cylinder 7, and a plurality of through rods 26 are provided with a second connector 6 at the end near the third pressure plate 21. The first connector 1 and the second connector 6 are used to connect with the building structure.
[0063] The viscous fluid is silicone oil.
[0064] like Figure 2 As shown, the second piston 12 is located in the middle of the annular groove 111. The distance between the second piston 12 and one end of the annular groove 111 is the same as the distance between the first pressure plate 19 and the fifth limiting nut 31. This distance is calculated using the following formula: d 1 =h · i e cos i d .
[0065] In the formula, d 1 represents the distance between the second piston 12 and one end of the annular groove 111. h For the building's structural floor height, i e The limit value for the elastic displacement angle of the building structure. i d It is the angle between the damper and the building structure when the damper is arranged.
[0066] The maximum distance that the first piston 8 and the second piston 12 can move is the same as the maximum compression of the first elastic element 16. This distance is calculated using the following formula: d =1.2· h · i i cos i d .
[0067] In the formula, d This represents the maximum distance that the first piston 8 and the second piston 12 can move. ii This refers to the limit value of the plastic displacement angle of the building structure.
[0068] The ultimate compression of the second elastic element 17 is calculated using the following formula: d 2 = 1.2 h · i i cos i d - d 1.
[0069] In the formula, d 2 represents the ultimate compression of the two elastic elements 17.
[0070] The diameter of piston rod 2 should meet the strength requirements: d rod ≥( n s 4 F / ps s ) 0.5 .
[0071] In the formula, d rod The diameter of piston rod 2 is... F For the maximum output of the damper, n s For safety margin, it is usually taken as 1.5 to 2.0. s s Let be the yield strength of the piston rod 2 material.
[0072] The diameter of piston rod 2 should meet the stability requirements: d rod ≥(64 F ⋅ n st ⋅( μL ) 2 / π 3 E ) 1 / 4 .
[0073] In the formula, L This is the maximum extension length of piston rod 2. E It is the elastic modulus of the piston rod 2 material. n st This is the stability safety factor, typically taken as 2.5 to 4. m This is a length coefficient, usually taken as 1 to 2, which determines the final diameter of piston rod 2. d rod The larger of the strength index calculation result and the stability index calculation result should be taken and rounded up to the standard size.
[0074] The diameter of the first piston 8 is calculated in the same way as the diameter of the second piston 12, using the following formula: D piston =(4 F viscous / πP max + d rod 2 ) 0.5 .
[0075] In the formula, D piston The diameter is either the diameter of the first piston 8 or the diameter of the second piston 12. F viscous This refers to the maximum output force of the first viscous damping mechanism 3 when there is no gap between the first cylinder 7 and the first piston 8, or the maximum output force of the second viscous damping mechanism 4 when there is no gap between the second cylinder 11 and the second piston 12. P max为 The maximum working pressure is usually taken as 15MPa~35MPa.
[0076] The wall thicknesses of the first cylinder block 7 and the second cylinder block 11 should satisfy the following formula: t ≥ D piston ·(([ s ] / ([ s ]-3 P max )) 0.5 -1) and t ≥ P max · D piston / [ s ].
[0077] In the formula, t The wall thickness of the first cylinder block 7 or the wall thickness of the second cylinder block 11, [ s ]= s s / n s When determining the wall thickness of the first cylinder block 7 or the second cylinder block 11, the larger of the calculation results from the two formulas above should be taken and rounded up to the standard size.
[0078] The calculation methods for the number and diameter of the first damping orifice 81 and the second damping orifice 121 are the same, both using the following formula: Fviscous =(3 α +1 / αn hole ) α ·(( D piston 2 - d rod 2 ) / 4) α ·( d hole / 2) -(3α+1) · πv k L hole ·( D piston 2 - d rod 2 - n hole · d hole 2 )· V α .
[0079] In the formula, n hole The number of the first damping orifice 81 or the number of the second damping orifice 121. d hole The diameter of the first damping orifice 81 or the diameter of the second damping orifice 121. α The damping exponent is typically taken as 0.2 to 1. v k The dynamic viscosity of silicone oil, L hole The length of the first damping orifice 81 or the length of the second damping orifice 121. V The damper experiences the maximum speed.
[0080] The diameter of the annular groove 111 is calculated using the following formula: F gap ={2 πv k L hole ·(( D piston 2 - d rod 2 ) / 4)·[ π (( D gap 2 -d rod 2 ) / 4)] α} / {(2 πα / ( α +1))·[(2 α +2 / 2 α +1)·( D piston / 2)·( D gap - D piston / 4) 2+1 / α +( D gap - D piston / 4) 3+1 / α ·(11 α 2+12 α +3) / ((2 α +1)(3 α +1))]+ παn / (3α+1)·( d hole / 2) 3+1 / α} α · V α .
[0081] In the formula, D gap The diameter of the annular groove 111 F gap This is the maximum output force of the second viscous damping mechanism 4 when the second piston 12 is in the annular groove 111.
[0082] Working principle: Both the first elastic element 16 and the second elastic element 17 are preloaded. The stiffness of the third elastic element 18 is less than that of the second elastic element 17. The third elastic element 18 may or may not be preloaded, but it must be ensured that when the first pressure plate 19 moves to the fifth limit nut 31, the load on the third elastic element 18 is equal to the preload on the second elastic element 17. Therefore, it can be ensured that the load of the self-resetting mechanism 5 does not change abruptly when transitioning from small stiffness to large stiffness. When the third elastic element 18 is not preloaded and its length is less than the distance between the first pressure plate 19 and the second pressure plate 20, the damper can achieve three-stage variable stiffness.
[0083] like Figure 3 , Figure 4As shown, when the damper generates a small compressive displacement, the piston rod 2 drives the first piston 8 to move to the right in the first cylinder 7. Silicone oil dissipates energy by passing through multiple first damping holes 81 on the first piston 8. Simultaneously, the piston rod 2 drives the second piston 12 to move to the right in the middle part of the second cylinder 11. Silicone oil dissipates a small amount of energy by passing through multiple second damping holes 121 on the second piston 12 and the gap between the second piston 12 and the annular groove 111. At the same time, the piston rod 2 drives the first drive nut 22 to move to the right. The first drive nut 22 then drives the first pressure plate 19 to compress the first elastic element 16 and the third elastic element 18. Since the load on the third elastic element 18 is less than the preload on the second elastic element 17, the second elastic element 17 will not be compressed.
[0084] like Figure 3 , Figure 6 As shown, when the damper generates a small tensile displacement, the piston rod 2 drives the first piston 8 to move to the left in the first cylinder 7. Silicone oil passes through multiple first damping holes 81 on the first piston 8 to dissipate energy. At the same time, the piston rod 2 drives the second piston 12 to move to the left in the middle part of the second cylinder 11. Silicone oil passes through multiple second damping holes 121 on the second piston 12 and the gap between the second piston 12 and the annular groove 111 to dissipate a small amount of energy. At the same time, the piston rod 2 drives the second drive nut 23 to move to the left. The second drive nut 23 then drives the third pressure plate 21 to compress the first elastic element 16. The third pressure plate 21 will also compress the second elastic element 17. However, since the load on the third elastic element 18 is less than the preload on the second elastic element 17, the second elastic element 17 will not be compressed. But the second elastic element 17 will drive the second pressure plate 20 to compress the third elastic element 18.
[0085] like Figure 3 , Figure 5 As shown, when the damper generates a large compressive displacement, the piston rod 2 drives the first piston 8 to move to the right in the first cylinder 7. Silicon oil passes through multiple first damping holes 81 on the first piston 8 to dissipate energy. At the same time, the piston rod 2 drives the second piston 12 to pass over the right end of the annular groove 11 in the second cylinder 11 and continue to move to the right. Silicon oil passes through multiple second damping holes 121 on the second piston 12 to dissipate a large amount of energy. At the same time, the piston rod 2 drives the first drive nut 22 to move to the right. The first drive nut 22 then drives the first pressure plate 19 to compress the first elastic element 16. The first pressure plate 19 also moves to the fifth limit nut 31, which will drive the fifth limit nut 31 to move to the right, thereby driving the second pressure plate 20 to compress the second elastic element 17 to the right.
[0086] like Figure 3 , Figure 7As shown, when the damper generates a large tensile displacement, the piston rod 2 drives the first piston 8 to move to the left in the first cylinder 7. Silicon oil passes through multiple first damping holes 81 on the first piston 8 to dissipate energy. At the same time, the piston rod 2 drives the second piston 12 to pass over the left end of the annular groove 111 in the second cylinder 11 and continue to move to the left. Silicon oil passes through multiple second damping holes 121 on the second piston 12 to dissipate a large amount of energy. At the same time, the piston rod 2 drives the second drive nut 23 to move to the left. The second drive nut 23 then drives the third pressure plate 21 to compress the first elastic element 16. The first pressure plate 19 also moves to the fifth limit nut 31. Therefore, the third pressure plate 21 will also compress the second elastic element 17.
[0087] The first elastic element 16 and the second elastic element 17 can also dissipate energy during compression. Regardless of whether the damper is under compression or tension, the first elastic element 16 and the second elastic element 17 are always compressed.
[0088] Both the first limiting nut 27 and the second limiting nut 28 are adjustable, thus ensuring that the preload of the first elastic element 16 and the second elastic element 17 is adjustable. At small displacements, the damper utilizes the first viscous damping mechanism 3 to provide a large amount of viscous damping energy and the second viscous damping mechanism 4 to provide a small amount of viscous damping energy, while the first elastic element 16 provides frictional damping energy. Stiffness is provided by the first elastic element 16 and the third elastic element 18. At large displacements, the damper utilizes both the first viscous damping mechanism 3 and the second viscous damping mechanism 4 to provide a large amount of viscous damping energy, while the first elastic element 16 and the second elastic element 17 simultaneously provide frictional damping energy. Stiffness is also provided by the first elastic element 16 and the second elastic element 17. Therefore, this damper can achieve variable viscous damping, frictional damping, and variable stiffness.
[0089] The variable stiffness and variable damping self-resetting viscous damper of the present invention has the following other advantages: First, this invention enables dual vibration control. Traditional dampers used for comfort control are difficult to use directly for structural safety dynamic response control due to output issues. Similarly, dampers used for structural safety dynamic response control cannot be used directly for comfort control. However, the variable stiffness and variable damping dual vibration control damper used in this invention can be used for both comfort and other vibration control, as well as structural safety dynamic response control.
[0090] Secondly, the present invention can not only perform variable damping, but also achieve variable stiffness, frictional energy dissipation and reset capability. The second elastic element does not activate at small displacements, and the first elastic element provides frictional energy dissipation capability, stiffness and reset capability. At large displacements, the first elastic element and the second elastic element simultaneously provide greater frictional energy dissipation capability, stiffness and reset capability, thereby realizing the change of stiffness and the change of viscous energy dissipation and frictional energy dissipation according to different levels of vibration / vibration control requirements.
[0091] Third, the present invention can achieve a smooth transition of load and stiffness. Due to the provision of a third elastic element, it can be ensured that the load of the self-resetting mechanism does not change abruptly when transitioning from small stiffness to large stiffness. When the third elastic element is not preloaded and its length is less than the distance between the first pressure plate and the second pressure plate, three-stage variable stiffness can be achieved.
[0092] Fourth, this invention can dissipate energy over a wide frequency range. Traditional self-resetting devices often use only a single energy dissipation mode, either displacement-related or velocity-related. Velocity-related energy dissipation has low energy dissipation efficiency in low-frequency vibration scenarios, while displacement-related energy dissipation is difficult to fully utilize when the vibration displacement is small. This invention combines displacement-related and velocity-related energy dissipation, and the two energy dissipation mechanisms can effectively complement each other, thereby efficiently dissipating energy over a wide frequency range. It has a wider range of applications and can simultaneously control the peak displacement, residual displacement, and peak acceleration of the structure.
[0093] Fifth, the present invention has excellent reset performance. Regardless of whether the damper is under tension or compression, the first elastic element and the second elastic element can always maintain a further compressed working state, thereby continuously ensuring that the device has a stable and excellent reset capability.
[0094] Sixth, the preload of the present invention can be flexibly adjusted. The preload of traditional self-resetting energy-consuming devices cannot be adjusted. The present invention adopts a rod-type connection design, which can change the distance between the pressure plates by adjusting the limit nut according to actual needs. Ultimately, it can conveniently adjust the preload of the first elastic element and the second elastic element without disassembling the device, which greatly improves the flexibility and ease of operation of preload adjustment.
[0095] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.
Claims
1. A variable stiffness, variable damping, self-resetting viscous damper, characterized in that, include: Piston rod; The first viscous damping mechanism includes a first cylinder through which the piston rod passes, and a first piston that can move back and forth along the inner wall of the first cylinder. The first cylinder stores a viscous fluid. The first piston is connected to the piston rod, and a first damping hole is also provided on the first piston along the axial direction of the piston rod. The second viscous damping mechanism includes a second cylinder that is passed through by the piston rod and fixedly connected to the first cylinder, and a second piston that can move back and forth along the inner wall of the second cylinder. The second cylinder also stores viscous fluid. An annular groove is also provided on the inner wall of the middle region of the second cylinder. The length of the annular groove is greater than the length of the second piston. A second damping hole is provided on the second piston. A self-resetting mechanism is provided at the end of the second cylinder and connected to the piston rod, and is configured to reset the piston rod after it has moved.
2. The variable stiffness and variable damping self-resetting viscous damper according to claim 1, characterized in that, The self-resetting mechanism includes: A first pressure plate, a second pressure plate, and a third pressure plate are arranged sequentially along the piston rod axis away from the second cylinder body. The piston rod also passes through the first pressure plate, the second pressure plate, and the third pressure plate in sequence and is slidably connected to them. A first drive nut and a second drive nut are detachably sleeved on the piston rod. The first drive nut can contact and abut against the first pressure plate from the outside, and the second drive nut can contact and abut against the second pressure plate from the outside. A first elastic element, sleeved on the piston rod, passes through the second pressure plate and is located between the first pressure plate and the third pressure plate; A second elastic element is fitted onto the first elastic element and located between the second pressure plate and the third pressure plate; And a third elastic element fitted on the first elastic element and located between the first pressure plate and the second pressure plate.
3. A variable stiffness variable damping self-resetting viscous damper according to claim 2, characterized in that, Several through rods are evenly arranged around the piston rod between the second cylinder and the third pressure plate. One end of the through rod is fixedly connected to the second cylinder, and the other end passes through the first pressure plate, the second pressure plate and the third pressure plate in sequence. A first limiting nut that can abut against the first pressure plate is also threaded on the side of the through rod near the second cylinder, and a second limiting nut that can abut against the third pressure plate from the outside is also threaded on the other end away from the first cylinder.
4. A variable stiffness variable damping self-resetting viscous damper according to claim 3, characterized in that, The piston rod is provided with a first connector at the end near the first cylinder, and the through rod is provided with a second connector at the end near the third pressure plate. The first connector and the second connector are configured to connect the building structure.
5. A variable stiffness variable damping self-resetting viscous damper according to claim 2, characterized in that, Between the second pressure plate and the third pressure plate, a number of first limiting screws are evenly arranged around the through rod. One end of each first limiting screw passes through the second pressure plate and is then threaded to a third limiting nut, while the other end passes through the third pressure plate and is then threaded to a fourth limiting nut.
6. A variable stiffness variable damping self-resetting viscous damper according to claim 2, characterized in that, A plurality of second limiting screws are provided between the first pressure plate and the second pressure plate. One end of the second limiting screw is fixedly connected to the second pressure plate, and the other end passes through the first pressure plate and is slidably connected to the first pressure plate. A fifth limiting nut is also threadedly connected to the second limiting screw at the position between the first pressure plate and the second pressure plate. The stiffness of the second elastic element is greater than the stiffness of the third elastic element.
7. A variable stiffness variable damping self-resetting viscous damper according to claim 6, characterized in that, The second piston is located in the middle of the annular groove under normal conditions. The distance between the second piston and one end of the annular groove is the same as the distance between the first pressure plate and the fifth limiting nut.
8. A variable stiffness variable damping self-resetting viscous damper according to claim 6, characterized in that, The maximum distance that the first piston and the second piston can move is the same as the maximum compression of the first elastic element.
9. A variable stiffness variable damping self-resetting viscous damper according to claim 2, characterized in that, The ultimate compression of the second elastic element satisfies: d 2=1.2× h × θ i ×cos θ d - d 1, d 1 =h × θ e ×cos θ d , in, d 1 represents the distance between the second piston and one end of the annular groove. h For the building's structural floor height, θ e The limit value for the elastic displacement angle of the building structure. θ d It is the angle between the damper and the building structure when they are arranged. θ i The limit value for the plastic displacement angle of the building structure. d 2 represents the ultimate compression of the second elastic element.
10. A variable stiffness variable damping self-resetting viscous damper according to claim 2, characterized in that, The viscous fluid is silicone oil.