Dual displacement amplification damping system based on rope and lever

Abstract

A dual-displacement amplification damping system based on a rope and a lever comprises fixed rolling wheels symmetrically arranged at the column end of a frame column, an upper suspension wall fixedly suspended below a frame beam and a viscous damper fixedly connected with the frame beam and transversely arranged, piston rods at the two ends of the viscous damper are connected with one ends of two steel strands respectively, and the other ends of the two steel strands are connected with the other ends of the two steel strands respectively. The other ends of the two steel strands respectively penetrate through symmetrically arranged fixed rollers, then bypass a lever free wheel mounted at the top end of a displacement amplification rod connected between the upper suspension wall and the lower vertical wall, then are connected with the lower vertical wall and are well anchored; when the structure vibrates, interlayer displacement is transmitted through the upper suspension wall and the lower vertical wall which are connected with the upper frame beam and the lower frame beam, and the interlayer displacement is amplified through the arrangement of the displacement amplification rods; through movement of the free end of the displacement amplification rod, the steel strand is stretched and amplified in a multiplied mode, the piston rod of the viscous damper is stretched, and the displacement of the viscous damper is amplified; according to the utility model, the large-multiple displacement amplification requirement and the displacement controllable requirement are realized.

Description

Technical Field

[0001] The utility model belongs to the technical field of building structure damper shock absorption, in particular to a double displacement amplification shock absorption system based on ropes and levers. Background Art

[0002] Damper shock absorption systems have been developed and widely used in new building construction and building renovation and reinforcement. Their inherent energy dissipation and shock absorption capabilities can effectively protect structures from earthquakes. However, in actual engineering applications, there is still the problem that the damper displacement is too small or it cannot be activated under small earthquakes, rendering the damper arrangement ineffective. Many scholars have also conducted research on displacement amplification shock absorption systems, but the results of amplification systems such as herringbone braces and toggle braces that amplify the damper displacement are less than ideal. Summary of the Invention

[0003] In order to overcome the deficiencies of the above-mentioned prior art, the purpose of the present invention is to provide a dual displacement amplification and shock absorption system based on ropes and levers, which is mainly composed of a displacement amplification rod part and a steel strand winding part. The displacement amplification rod is arranged between the upper cantilever wall and the lower vertical wall. The displacement amplification rod can control the proportion of inter-story displacement amplification, and the steel strand connected to the viscous damper can multiply the displacement of the viscous damper by winding between fixed rollers. These two parts are connected in series to achieve a dual amplification effect of the viscous damper displacement, so that the displacement of the viscous damper is amplified to a considerable effect. In addition, the displacement amplification factor requirement can be controlled according to the actual engineering conditions and the specifications of the viscous damper, thereby achieving the requirements of large-multiple displacement amplification and controllable displacement.

[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0005] A dual displacement amplification and shock absorption system based on ropes and levers includes symmetrically arranged fixed rollers 7 on the ends of frame columns 1 near frame beams 2, an upper cantilever wall 4 suspended under the frame beams 2, and a transversely arranged viscous damper 3 located in the middle of the upper cantilever wall 4 and fixed to the frame beams 2. The piston rods at both ends of the viscous damper 3 are respectively connected to one end of two steel strands 8. The other ends of the two steel strands 8 pass through the symmetrically arranged fixed rollers 7 and then pass around the lever free wheel 10 installed at the top of the displacement amplification rod 6 connected between the upper cantilever wall 4 and the lower vertical wall 5, and then are connected to the lower vertical wall 5 and anchored.

[0006] The top end of the displacement amplification rod 6 is a free end, and an upper end hole 18 is opened at the top end of the displacement amplification rod 6. The lever free wheel 10 is inserted into the upper end hole 18 through the free wheel pin 22 therein. An intermediate hole 17 is opened at the middle and lower part of the displacement amplification rod 6, and a movable pin 9 is provided in the intermediate hole 17. The displacement amplification rod 6 is connected to the upper hanging wall 4 through the movable pin 9. The bottom end of the displacement amplification rod 6 is opened at the lower end hole 16, and a pin is provided in the lower end hole 16. The bottom end of the displacement amplification rod 6 is connected to the lower vertical wall 5 through the pin.

[0007] The upper cantilever wall 4 is in an inverted triangle shape, the upper end of the inverted triangle is suspended on the frame beam 2 for transmitting inter-story displacement, and the lower end of the inverted triangle is connected to the displacement amplification rod 6 for transmitting the inter-story displacement to the contact point with the displacement amplification rod 6;

[0008] The upper end of the upper hanging wall 4 in an inverted triangle shape is horizontally provided with an upper hanging wall first groove 11, and the viscous damper 3 is arranged in the upper hanging wall first groove 11. The piston rods at both ends of the viscous damper 3 can move freely left and right in the upper hanging wall first groove 11;

[0009] The upper cantilever wall 4, which is in an inverted triangle shape, has symmetrically formed third cantilever wall grooves 14 at both ends of its upper portion. The viscous damper 3 is arranged on the upper cantilever wall plate 25 formed within the first cantilever wall groove 11. The two steel strands 8 connecting the piston rods at both ends of the viscous damper 3 are freely stretched within the third cantilever wall groove 14.

[0010] The upper hanging wall 4 is provided with upper hanging wall second grooves 12 on the two oblique sides of the upper hanging wall 4 in an inverted triangle shape, for the steel strand 8 to pass through the upper hanging wall second grooves 12;

[0011] The bottom end of the upper hanging wall 4 in the shape of an inverted triangle is provided with an upper hanging wall fourth groove 24 for passing the displacement amplification rod 6. The width of the upper hanging wall fourth groove 24 is the same as the width of the displacement amplification rod 6. An upper hanging wall fifth groove 26 is provided in the upper hanging wall fourth groove 24. The upper hanging wall fifth groove 26 is elliptical, and the horizontal dimension of the ellipse is equal to the middle hole 17 of the displacement amplification rod 6.

[0012] The fixed roller 7 is symmetrically fixed to the column end of the frame column 1 near the upper frame beam 2 through a base. The fixed roller 7 includes a fixed roller support 19 and a roller 21. The roller 21 is connected to the fixed roller support 19 through a fixed roller pin 20. A fixed roller groove 13 is provided on the roller 21 for placing the steel strand 8.

[0013] The lever free wheel 10 includes two free wheels 23 , which are connected to the displacement amplification rod 6 via a free wheel stopper 22 . Both free wheels 23 are provided with a free wheel groove 15 for placing the steel strand 8 .

[0014] The upper cantilever wall 4 , the lower vertical wall 5 , the displacement amplifying rod 6 , the lever free wheel 10 and the viscous damper 3 are all arranged along the axis of the center of the frame 2 .

[0015] The two steel strands 8 and the fixed roller 7 are symmetrically arranged along the axis of the center of the frame 2 .

[0016] Compared with the prior art, the beneficial effects of the present invention are:

[0017] 1. Compared with the existing BRB steel support type reinforcement method, the present invention uses the steel strand 8 to drive the viscous damper 3 to work, which is economical, lightweight and simple to construct.

[0018] 2. The present invention utilizes the flexibility of the steel strand 8, winds it between two fixed rollers 7 and a lever free wheel 10, and utilizes the movable pulley law to multiply the displacement amplification efficiency of the viscous damper 3.

[0019] 3. The present invention fixes the displacement amplification rod 6 between the lower vertical wall 5 and the upper cantilever wall 4, which not only can proportionally amplify the inter-story displacement, but also allows the steel strand 8 to be directly wound around the lever free wheel 10, saving space on both sides of the frame and increasing space utilization.

[0020] In summary, the present invention utilizes the characteristics of the steel strand 8 being light, economical and flexible. By winding the steel strand 8 in series with the displacement amplification rod 6, it has the purpose of dual displacement amplification of the viscous damper 3, and the displacement amplification multiple of the viscous damper 3 can be controlled by adjusting the height of the displacement amplification rod 6 and the number of wound strands of the steel strand 8. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a front view of the overall structure of the utility model.

[0022] Figure 2 This is a schematic diagram of the structure of the upper hanging wall 4 of the utility model; wherein, Figure 2 (a) is a front view of the upper hanging wall 4. Figure 2 (b) is a side structural diagram of the upper cantilever wall 4, Figure 2 (c) is a top view of the upper cantilever wall 4.

[0023] Figure 3 This is a schematic diagram of the structure of the fixed roller 7 of the utility model, wherein: Figure 3 (a) is a front view of the fixed roller 7, Figure 3 (b) is a side view of the fixed roller 7.

[0024] Figure 4 This is a schematic diagram of the structure of the lever free wheel 10 of the utility model, wherein: Figure 4(a) is a front view of the lever free wheel 10, Figure 4 (a) is a side view of the lever freewheel 10.

[0025] Figure 5 It is a structural schematic diagram of the displacement amplifying rod 6 of the present utility model.

[0026] In the figure: 1 is a frame column, 2 is a frame beam, 3 is a viscous damper, 4 is an upper hanging wall, 5 is a lower vertical wall, 6 is a displacement amplification rod, 7 is a fixed roller, 8 is a steel strand, 9 is a movable pin, 10 is a lever freewheel, 11 is a first groove of the upper hanging wall, 12 is a second groove of the upper hanging wall, 13 is a fixed roller groove, 14 is a third groove of the upper hanging wall, 15 is a freewheel groove, 16 is a lower end hole, 17 is a middle hole, 18 is an upper end hole, 19 is a fixed roller support, 20 is a fixed roller pin, 21 is a roller, 22 is a freewheel pin, 23 is a freewheel, 24 is a fourth groove of the upper hanging wall, 25 is an upper hanging wall plate, and 26 is a fifth groove of the upper hanging wall. DETAILED DESCRIPTION

[0027] The technical solution adopted by the utility model will be further introduced below with reference to the accompanying drawings.

[0028] like Figure 1 As shown, a dual displacement amplification and shock absorption system based on ropes and levers is shown, and the shock absorption system is composed of two displacement amplification parts in series; the first part is the lever amplification part, in which the upper hanging wall 4 is welded to the upper frame beam 2, and the lower vertical wall 5 is welded to the lower frame beam 2, the lower end hole 16 of the displacement amplification rod 6 is hinged to the lower vertical wall 5, and the displacement amplification rod 6 is entirely embedded in the fourth groove 24 of the upper hanging wall, and the middle hole 17 of the displacement amplification rod 6 is connected to the fifth groove 26 of the upper hanging wall through a pin; the second part is the steel strand movable pulley amplification part, the fixed end of the steel strand 8 is anchored on the lower vertical wall 5, and the steel strand 8 is connected to the lower vertical wall 5. The other end passes through the freewheel 23 on the free end of the displacement amplification rod 6 and winds around the roller 21 on the fixed roller 7. The free end of the displacement amplification rod 6 is equipped with a lever freewheel 10, which is provided with a freewheel groove 15 for winding the steel strand 8. The bottom support of the fixed roller 7 is welded to the end of the frame column 1, and the roller is provided with a fixed roller groove 13 for winding the steel strand 8. After winding, the steel strand 8 is ultimately anchored to the piston rod of the viscous damper 3. The middle tube of the viscous damper 3 is fixed in the first groove 11 of the upper cantilever wall. The piston rod of the viscous damper 3 can move under the tension of the steel strand 8.

[0029] like Figure 1As shown, a dual displacement amplification and shock absorption system based on ropes and levers is shown. The upper cantilever wall 4 and the lower vertical wall 5 are located between the frame column 1 and the frame beam 2. The upper cantilever wall 4 and the lower vertical wall 5 are both composed of assembled steel plates and are welded to the upper and lower parts of the frame beam 2, respectively. The displacement amplification rod 6 is arranged between the upper cantilever wall 4 and the lower vertical wall 5. Fixed rollers 7 are symmetrically arranged at the column ends of the frame beam 2 near the upper part. The viscous damper 3 is fixedly installed on the upper cantilever wall plate 25 of the upper cantilever wall 4. A first upper cantilever wall groove 11 is opened on the upper cantilever wall 4. The piston rods at both ends of the viscous damper 3 can move freely left and right in the first upper cantilever wall groove 11 and move parallel to the frame beam 2. The piston rods at both ends of the viscous damper 3 are connected to the lower vertical wall 5 through two steel strands 8 through the fixed rollers 7 and the lever free wheel 10 on the displacement amplification rod 6.

[0030] like Figure 2 As shown, the upper cantilever wall 4 is in an inverted triangle shape, the upper end of the inverted triangle is suspended on the frame beam 2 for transmitting inter-story displacement, and the lower end of the inverted triangle is connected to the displacement amplification rod 6 for transmitting the inter-story displacement to the contact point with the displacement amplification rod 6;

[0031] A first upper hanging wall groove 11 is horizontally opened at the upper end of the upper hanging wall 4 in an inverted triangle shape. The viscous damper 3 can be placed on the upper hanging wall plate 25 in the first upper hanging wall groove 11. The two steel strands 8 connecting the piston rods at both ends of the viscous damper 3 are freely stretched in the upper hanging wall third groove 14 symmetrically opened at both ends of the upper part of the upper hanging wall 4. The two steel strands 8 can pass through the upper hanging wall second groove 12 opened on the oblique sides of the lower end of the upper hanging wall 4. The bottom end of the upper hanging wall 4 in an inverted triangle shape is opened with an upper hanging wall fourth groove 24 for passing the displacement amplification rod 6. The width of the upper hanging wall fourth groove 24 is the same as the width of the displacement amplification rod 6. In order to meet the rotation of the displacement amplification rod 6 in the upper hanging wall fourth groove 24, an upper hanging wall fifth groove 26 is opened in the upper hanging wall fourth groove 24 to control the rotation of the displacement amplification rod 6 under increasing or decreasing displacement. The upper hanging wall fifth groove 26 is elliptical, and the horizontal dimension of the ellipse is equal to the middle hole 17 of the displacement amplification rod 6.

[0032] The overall upper cantilever wall 4 is in the shape of an inverted triangle. The surface area of ​​the upper cantilever wall 4 in contact with the frame beam 2 is large, namely the upper end of the inverted triangle, which is used to transfer inter-story displacement and avoid stress concentration in one place; the area of ​​the part in contact with the displacement amplification rod 6 is small, namely the lower end of the inverted triangle, which is used to transfer the inter-story displacement to the contact point with the displacement amplification rod 6. Compared with the rectangular upper cantilever wall, this shape design saves steel while fully transferring the inter-story displacement.

[0033] The displacement amplification rod 6 needs to pass through the fourth upper hanging wall groove 24 reserved on the upper hanging wall 4, and the fourth upper hanging wall groove 24 can limit the out-of-plane rotation of the displacement amplification rod 6 and ensure that the displacement amplification rod 6 will not touch the fourth upper hanging wall groove 24 during rotation.

[0034] The viscous damper 3 needs to be a double-rod damper.

[0035] like Figure 5 As shown, the middle hole 17 of the displacement amplification rod 6 is mounted on the upper cantilever wall 4 via a movable pin 9. The lower hole 16 is hinged to the lower vertical wall 5, while the upper hole 18 remains free. This installation method ensures that the displacement amplification rod 6 can rotate along the lower hinge under external loads. A movable pin hole is provided at the movable pin 9 of the displacement amplification rod 6, and an elliptical pin hole is provided in the upper cantilever wall 4 to which it is connected, allowing the displacement amplification rod 6 to rotate accordingly.

[0036] A lever free wheel 10 is installed at the upper free end of the displacement amplification rod 6 so that the steel strand 8 can be wound around the lever free wheel 10 .

[0037] On the fixed roller 7 , the steel strand 8 is also continuously wound on the fixed roller 7 and the lever free wheel 10 .

[0038] The contact surface between the fixed roller 7 and the free end of the displacement amplification rod 6 is oiled and smoothed, and the roller 21 in the fixed roller 7 and the fixed roller pin 20 to which it is connected are also oiled and smoothed to keep the friction coefficient small, so that during the stretching process of the steel strand 8, the fixed roller 7 can roll with it, reducing the influence of its friction force.

[0039] like Figure 3 As shown, the fixed roller 7 is symmetrically fixed to the column end of the frame column 1 near the upper frame beam 2 via a base. The fixed roller 7 includes a fixed roller support 19 and a roller 21. The roller 21 is connected to the fixed roller support 19 via a fixed roller pin 20. The roller 21 is provided with a fixed roller groove 13 for accommodating the steel strand 8. The steel strand 8 can slide in the fixed roller groove 13, and the fixed roller 7 can rotate as the steel strand 8 is stretched.

[0040] like Figure 4 As shown, the lever freewheel 10 includes two freewheels 23, which are connected to the displacement amplification rod 6 via a freewheel stopper 22. Both freewheels 23 are provided with a freewheel groove 15 for mounting two steel strands 8. Due to the pin connection of the lever freewheel 10, the free end of the displacement amplification rod 6 can roll during the stretching process of the steel strand 8.

[0041] One end of the steel strand 8 is anchored on the lower vertical wall 5, and the other end is finally anchored on the piston rod of the viscous damper 3 through the lever free wheel 10 and the fixed roller 7; during the stretching process of the steel strand 8, one end remains stationary, while the other end drives the piston rod of the viscous damper 3 to move.

[0042] The two steel strands 8 can be wound into the freewheel groove 15 on the lever freewheel 10 and into the first roller groove 13 of the fixed roller 7 .

[0043] In the present invention, the displacement amplification is mainly composed of two parts. One is the displacement amplification rod 6. By setting the lever component, the inter-layer displacement can be amplified in the same proportion under the action of external load. Figure 1 As shown, the displacement amplification rod 6 has a 2:1 ratio of up to down, thus doubling the amplification effect. The other part is the steel strand 8 wound around the two free wheels 23 of the lever free wheel 10 provided on the free end of the displacement amplification rod 6 and the rollers 21 of the fixed rollers 7 fixed to the ends of the two frame columns 1. Based on the principle of movable pulleys, during the movement of the free end of the displacement amplification rod 6, the steel strand 8 is stretched and the stretched length of the steel strand 8 is amplified. The stretched length of the steel strand 8 is determined by the number of steel strands between the two ends of the winding (actually, one strand is wound). Figure 1 The number of strands wound between the central fixed roller 7 and the lever freewheel 10 is 5, resulting in a displacement amplification factor of 5. However, due to factors such as the elastic deformation of the steel strands 8, some pin friction, and inter-story displacement of the frame structure itself, the actual amplification factor can be controlled to approximately 4. Since the two components are connected in series, the viscous damper 3 is subjected to dual displacement amplification, with an amplification factor of approximately 8. This amplification factor can be adjusted according to actual conditions, providing a certain degree of adjustability.

[0044] The utility model solves the problem that the energy dissipation effect of some damper structures used for building shock absorption in the above-mentioned background technology cannot fully exert their energy dissipation capacity due to the small deformation displacement, and that the general damper amplification system consumes more amplified displacement at low displacement levels by the structure itself and cannot fully act on the damper itself.

[0045] The working principle of this utility model is:

[0046] When the structure is subjected to external loads, the frame undergoes lateral deformation, generating an inter-story drift angle between the frame columns 1 and the frame beams 2. This ultimately leads to relative inter-story drift between the upper and lower frame beams 2, which in turn translates into relative displacement between the upper cantilever wall 4 and the lower vertical wall 5. When this relative displacement occurs, the displacement amplification rod 6, due to its installation and proportional relationship, converts the relative displacement between the upper cantilever wall 4 and the lower vertical wall 5 into a linear displacement at the upper end of the displacement amplification rod 6. This linear displacement is amplified by the proportional relationship of the displacement amplification rod 6. As the displacement amplification rod 6 rotates along its lower hinge, the lever freewheel 10 at its top moves, stretching the steel strand 8. The stretching length is primarily related to the number of turns between the lever freewheel 10 and the fixed roller 7. This displacement amplification mechanism is similar to that of a fixed pulley, thereby pulling the piston rod of the viscous damper 3 to move.

[0047] Displacement amplification efficiency

[0048] Assuming that the inter-story displacement of the frame is f, the displacement of the viscous damper is δ, the angle between the strands of the steel strand connected to the lower vertical wall and the free end of the displacement amplification rod is θ1, and the angle between the displacement amplification rod and the fixed pulley support is θ2, the displacement amplification coefficient n1 is calculated as follows:

[0049]

[0050] The displacement amplification efficiency is derived from the design of this vibration reduction system and is the theoretical displacement amplification factor.

Claims

1. A double displacement amplification and shock absorption system based on ropes and levers, characterized in that: The invention comprises fixed rollers (7) symmetrically arranged on the ends of frame columns (1) close to the frame beam (2), an upper hanging wall (4) suspended below the frame beam (2), a viscous damper (3) arranged transversely in the middle of the upper hanging wall (4) and fixed to the frame beam (2), piston rods at both ends of the viscous damper (3) are respectively connected to one end of two steel strands (8), and the other ends of the two steel strands (8) respectively pass through the symmetrically arranged fixed rollers (7) and then pass around a lever free wheel (10) installed at the top of a displacement amplification rod (6) connected between the upper hanging wall (4) and the lower vertical wall (5), and then are connected to the lower vertical wall (5) and anchored.

2. The double displacement amplification and shock absorption system based on ropes and levers according to claim 1, characterized in that: The top end of the displacement amplifying rod (6) is a free end. The top end of the displacement amplifying rod (6) is provided with an upper end hole (18). The lever free wheel (10) is inserted into the upper end hole (18) through the free wheel pin (22) therein. The middle and lower part of the displacement amplifying rod (6) is provided with an intermediate hole (17). A movable pin (9) is provided in the intermediate hole (17). The displacement amplifying rod (6) is connected to the upper hanging wall (4) through the movable pin (9). The bottom end of the displacement amplifying rod (6) is provided with a lower end hole (16). A pin is provided in the lower end hole (16). The bottom end of the displacement amplifying rod (6) is connected to the lower vertical wall (5) through the pin.

3. The double displacement amplification and shock absorption system based on ropes and levers according to claim 1, characterized in that: The upper hanging wall (4) is in an inverted triangle shape, the upper end of the inverted triangle shape is suspended on the frame beam (2) and is used to transmit inter-story displacement, and the lower end of the inverted triangle shape is connected to the displacement amplification rod (6) and is used to transmit the inter-story displacement to the contact point with the displacement amplification rod (6); A first upper hanging wall groove (11) is transversely provided at the upper end of the upper hanging wall (4) in an inverted triangle shape, a viscous damper (3) is provided in the first upper hanging wall groove (11), and piston rods at both ends of the viscous damper (3) can freely move left and right in the first upper hanging wall groove (11); The upper ends of the upper hanging wall (4) in an inverted triangle shape are symmetrically provided with upper hanging wall third grooves (14); the viscous damper (3) is arranged on the upper hanging wall plate (25) formed inside the upper hanging wall first groove (11); and two steel strands (8) connecting the piston rods at both ends of the viscous damper (3) are freely stretched in the upper hanging wall third groove (14); The upper hanging wall (4) is provided with upper hanging wall second grooves (12) on two oblique sides of the upper hanging wall (4) in an inverted triangle shape, for the steel strand (8) to pass through the upper hanging wall second grooves (12); The bottom end of the upper hanging wall (4) in an inverted triangle shape is provided with an upper hanging wall fourth groove (24) for passing the displacement amplifying rod (6), the width of the upper hanging wall fourth groove (24) is the same as the width of the displacement amplifying rod (6), and an upper hanging wall fifth groove (26) is provided in the upper hanging wall fourth groove (24), the upper hanging wall fifth groove (26) is elliptical, and the horizontal dimension of the elliptical shape is equal to the middle hole (17) of the displacement amplifying rod (6).

4. The double displacement amplification and shock absorption system based on ropes and levers according to claim 1, characterized in that: The fixed roller (7) is symmetrically fixed to the column end of the frame column (1) close to the upper frame beam (2) through a base. The fixed roller (7) includes a fixed roller support (19) and a roller (21). The roller (21) is connected to the fixed roller support (19) through a fixed roller pin (20). The roller (21) is provided with a fixed roller groove (13) for placing the steel strand (8).

5. The double displacement amplification and shock absorption system based on ropes and levers according to claim 1, characterized in that: The lever free wheel (10) comprises two free wheels (23), which are connected to the displacement amplification rod (6) via a free wheel pin (22). Both free wheels (23) are provided with a free wheel groove (15) for placing the steel strand (8).

6. The double displacement amplification and shock absorption system based on ropes and levers according to claim 1, characterized in that: The upper hanging wall (4), the lower vertical wall (5), the displacement amplifying rod (6), the lever free wheel (10) and the viscous damper (3) are all arranged along the axis of the center of the frame beam (2).

7. The double displacement amplification and shock absorption system based on ropes and levers according to claim 1, characterized in that: The two steel strands (8) and the fixed roller (7) are symmetrically arranged along the axis of the center of the frame beam (2).

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