A SMA-based torsional amplification damper and its working method

Abstract

The present invention relates to a torsion amplification damper based on SMA and its working method. The torsion amplification damper based on SMA includes a damper outer wall, a slit torsion member, a large gear, a small gear, a steel rod, a steel sheet, a connecting rod, and a heating device. Under the action of horizontal wind and / or earthquake, inter-story deformation occurs in the building. Through the amplification effect of the gear combination, the torsional deformation of the slit torsion member is aggravated, the energy dissipation of the building is increased, and the energy dissipation efficiency is significantly improved, effectively reducing the damage to the building structure. At the same time, the slit torsion member uses shape memory alloy material (SMA), and its unique property can restore the original shape after deformation, realizing the reuse of the member. Compared with the prior art, the present invention has no pollution, low noise, can be reused, and has excellent energy dissipation performance.

Description

Technical Field

[0001] The present invention relates to the technical field of civil structure vibration control, and particularly relates to a torsion amplification damper based on SMA and its working method. Background Art

[0002] In recent years, passive control technologies such as base isolation, energy dissipation shock absorption, and tuned shock absorption control have been widely used in civil engineering at home and abroad due to their simple concepts, clear mechanisms, low costs, and remarkable shock absorption effects.

[0003] However, the existing dampers still have certain deficiencies. For example, dampers that use impact collision energy dissipation will generate noise and discomfort during operation; dampers that use metal deformation energy dissipation need to be replaced in time after metal deformation; viscous liquid dampers may leak and pollute the environment; torsion dampers are less used in the construction field and have limited torsional deformation ability, etc. Therefore, it is necessary to improve on the existing damping technology to obtain a damper that is pollution-free, low-noise, reusable, and has excellent energy dissipation ability.

[0004] CN112459586A discloses a displacement amplification damper that uses large and small gears to connect the buckling-restrained SMA rod and the rigid rod. The large gear meshes with the rigid rod welded with a rack, and the small gear meshes with the rigid rod welded with a rack. By designing different radii of the large and small gears, the displacement amplification coefficient is controlled. A set of concentric circle gears are fixed in the steel plate by a steel shaft. The large gear meshes tightly with the rack welded on the lower rigid rod. The buckling-restrained SMA rod is fixed in the steel plate by high-strength nuts. A section of rack is welded on the rigid rod between the two buckling-restrained SMA rods and meshes tightly with the small gear. The energy dissipation ability of the damper mainly comes from the deformation energy dissipation of the SMA rod. At the same time, by changing the radius ratio of the large and small dampers during design, the amplification of displacement is achieved. However, the energy dissipation ability of this displacement amplification damper is limited by the lengths of the upper and lower racks. In the case where large inter-story displacements may occur, to ensure sufficient displacement, a larger rack length is required; at the same time, to ensure that as much energy as possible is dissipated by buckling, a larger longitudinal movement space is required for the damper, which may limit its application in some buildings; in addition, under the repeated action of cyclic loads, the possibility of damage is greater at the section shape change.

[0005] To achieve the above objectives, there is an urgent need for a torsion amplification damper based on SMA to solve problems such as high noise during use, limited energy dissipation ability, and non-reusability of components of traditional dampers. Summary of the Invention

[0006] The object of the present invention is to overcome the defects of the above-mentioned existing technologies and provide a SMA-based torsional amplification damper and its working method. This torsional amplification damper utilizes the plastic deformation generated during the torsion of the slit to consume energy. The arrangement of the large and small gears amplifies the torsion of the component, increasing the energy dissipation, and the use of SMA material makes it possible to be reused. Specifically: by using the rotation between the gears to amplify the torsion of the slit torsion component, it improves the defect that the torsional effect of the traditional torsional damper is not obvious, enhances the energy dissipation capacity, and at the same time, applying SMA as the material of the slit torsion device realizes the reuse of the energy dissipation component. It is a damper with no pollution, low noise, reusable, and excellent energy dissipation performance.

[0007] The object of the present invention can be achieved through the following technical solutions:

[0008] The first object of the present invention is to provide a SMA-based torsional amplification damper, including a damper outer wall, a slit torsion component, a large gear, a small gear, a steel rod, a steel sheet, and a connecting rod; the damper outer wall is fixedly connected to the main structure of the building; one side of the slit torsion component is connected to the small gear, and the other side is connected to the damper outer wall; the large gear meshes with the small gear; the steel sheet is rigidly connected to the steel rod; the steel sheet is connected to the connecting rod; the steel rod is connected to the large gear; the SMA-based torsional amplification damper further includes a heating device; the heating device is connected to the slit torsion component.

[0009] Further, the heating device includes an AC power supply, an overheat protection device, and a coil; the AC power supply, the overheat protection device, and the coil are connected in series.

[0010] Further, the coil is wound on the surface of the slit torsion component and there is a certain space reserved between the coil and the surface of the slit torsion component.

[0011] Further, the material of the coil is copper tube.

[0012] Further, the SMA-based torsional amplification damper further includes bolts; one side of the slit torsion component is connected to the small gear through bolts, and the other side is connected to the damper outer wall through bolts.

[0013] Further, the material of the slit torsion component is shape memory alloy (SMA). This material can restore its original shape at high temperature. Using this property, the slit torsion component that has undergone plastic deformation can be heated by the heating device to restore its original shape and achieve reuse.

[0014] Further, the damper outer wall is a cuboid or cylindrical cavity welded by steel plates.

[0015] Furthermore, the outer wall of the damper is a cuboid or cylindrical cavity welded by steel plates with a thickness of 5 mm - 10 mm.

[0016] Furthermore, the outer walls of the damper are arranged individually or in multiple numbers horizontally and / or vertically.

[0017] Furthermore, the rotation of the large gear drives the rotation of the small gear. According to the geometric relationship, the rotation of the small gear increases significantly compared to the large gear, causing an increase in the plastic deformation of the slit torsion member, that is, amplifying the torsional deformation of the slit torsion member and improving the energy dissipation capacity.

[0018] Furthermore, parameters such as the slit width and slit height of the slit torsion member can be adjusted to obtain the optimal parameters matching the building.

[0019] Furthermore, parameters such as the radius and number of teeth of the large gear and the small gear can be adjusted, and the transmission ratio can be selected according to different situations.

[0020] The above SMA-based torsional amplification damper is applied to the field of vibration control of civil structures (including high-rise buildings, high-rise structures, bridge structures, etc.).

[0021] The second object of the present invention is to provide a working method of the above SMA-based torsional amplification damper. When inter-story deformation occurs in a building, the displacement of the main structure of the building drives the connecting rod connected thereto, and the connecting rod causes the steel sheet to rotate. Through the rigid connection between the steel sheet and the steel rod, the large gear is driven to rotate, and the large gear drives the small gear to rotate. During the rotation of the small gear, the slit torsion member is driven to twist.

[0022] Furthermore, the heating device raises the temperature of the slit torsion member, and the slit torsion member returns to its initial state when reaching the transformation temperature, realizing the reuse of the slit torsion member.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1) Under the action of horizontal wind or / and earthquake, when inter-story deformation occurs in a building, the SMA-based torsional amplification damper of the present invention, through the amplification effect of the gear combination, intensifies the torsional deformation of the slit torsion member, increases the energy dissipation of the building, significantly improves the energy dissipation efficiency, and effectively reduces the damage to the building structure.

[0025] 2) The present invention uses the metal torsional plastic deformation of the slit torsion member to consume energy. The slit torsion member is made of a shape memory alloy material, and the inherent characteristics of this material can be restored to its original state after heating after deformation, realizing the reuse of the member and reducing the cost of multiple replacements of the member.

[0026] 3) In the present invention, the torsion is driven by a gear set. The large gear rotates first to drive the small gear to rotate. According to the geometric relationship, l = θR. When rotating the same radian, the gear with a smaller radius rotates through a larger angle. That is, the rotation of the small gear is amplified, increasing the torsional deformation of the energy-consuming component and making up for the defect that the energy dissipation capacity of the damper is limited under small deformations, thus improving the energy dissipation capacity.

[0027] 4) In the present invention, by adjusting parameters such as the width and height of the slit in the slit torsion member, it can fully adapt to different buildings, find the optimal parameters suitable for different buildings, and at the same time, the number of small gears can be selected and set according to needs, with high applicability.

[0028] 5) The energy dissipation of the present invention is through plastic deformation, reducing the noise during the operation of the device and the discomfort of people in the building. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is the front view of a SMA-based torsion amplification damper of the present invention.

[0030] Figure 2 is the side view of a SMA-based torsion amplification damper of the present invention.

[0031] Figure 3 is the schematic diagram of the slit torsion member and the heating device of a SMA-based torsion amplification damper of the present invention.

[0032] Figure 4 is Figure 3 the sectional view in the a-a direction of

[0033] Figure 5 is the schematic diagram of the heating device circuit of a SMA-based torsion amplification damper of the present invention.

[0034] The reference numerals in the figures indicate:

[0035] 1 is the outer wall of the damper, 2 is the slit torsion member, 3 is the large gear, 4 is the small gear, 5 is the steel rod, 6 is the steel sheet, 7 is the bolt, 8 is the connecting rod, 9 is the heating device;

[0036] 901 is the coil, 902 is the overheat protection device, 903 is the AC power supply. DETAILED DESCRIPTION OF THE INVENTION

[0037] The present invention will be described in detail below with reference to the drawings and specific embodiments. Features such as component models, material names, connection structures, control methods, etc. that are not clearly described in the present technical solution are all regarded as common technical features disclosed in the prior art.

[0038] A SMA-based torsional amplification damper of the present invention includes: a damper outer wall 1, a slit torsion member 2, a large gear 3, a small gear 4, a steel rod 5, a steel sheet 6, a bolt 7, a connecting rod 8, and a heating device 9. It is characterized in that: the damper outer wall 1 is in a cuboid or cylinder structure, which can be single or multiple horizontally and / or vertically arranged; the main internal components are a gear set composed of the large gear 3 and the small gear 4 and the slit torsion member 2 rigidly connected to the small gear 4; when inter-story deformation occurs in a building, the displacement of the main structure of the building drives the connecting rod 8 connected thereto, and the connecting rod 8 causes the steel sheet 6 to rotate. Through the rigid connection between the steel sheet 6 and the steel rod 5, the large gear 3 and the small gear 4 are driven to rotate. During the rotation of the gears, the slit torsion member 2 will be driven to undergo torsional deformation and consume energy; one side of the slit torsion member 2 is connected to the small gear 4 through the bolt 7, and the other side is connected to the damper outer wall 1 through the bolt 7.

[0039] In the present invention, the rotation of the large gear 3 drives the rotation of the small gear 4. According to the geometric relationship, the rotation of the small gear 4 is significantly increased compared with that of the large gear 3, so that the plastic deformation of the slit torsion member 2 is increased, that is, the torsional deformation of the slit torsion member 2 is amplified, and the energy dissipation capacity is improved.

[0040] In the present invention, the material of the slit torsion member 2 is shape memory alloy (SMA). This material can restore its original shape at high temperature. Using this property, the plastically deformed slit torsion member 2 can be heated by the heating device 9 to restore its original shape and achieve reuse.

[0041] In the present invention, parameters such as the slit width and slit height of the slit torsion member 2 can be adjusted to obtain the optimal parameters matching the building. Parameters such as the radius and number of teeth of the large gear 3 and the small gear 4 can be adjusted, and the transmission ratio can be selected according to different situations.

[0042] Embodiment

[0043] As Figures 1 to 5 shown, this embodiment provides a SMA-based torsional amplification damper, including a damper outer wall 1, a slit torsion member 2, a large gear 3, a small gear 4, a steel rod 5, a steel sheet 6, a bolt 7, a connecting rod 8, and a heating device 9.

[0044] The damper outer wall 1 is a cuboid or cylinder cavity welded by steel plates with a thickness of 5 mm - 10 mm. The damper outer wall 1 is fixedly connected to the main structure of the building in a certain way; one side of the slit torsion member 2 is connected to the small gear 4 through the bolt 7, and the other side is connected to the damper outer wall 1 through the bolt 7; the large gear 3 meshes with the small gear 4; the steel sheet 6 is rigidly connected to the steel rod 5; the steel sheet 6 is connected to the connecting rod 8; the steel rod 5 is connected to the large gear 3; the heating device 9 is connected to the slit torsion member 2.

[0045] The heating device 9 includes an AC power supply 903, an overheat protection device 902, and a coil 901; the AC power supply 903, the overheat protection device 902, and the coil 901 are connected in series; the coil 901 is wound around the surface of the slit torsion member 2 and there is a certain space reserved from the surface of the slit torsion member 2.

[0046] The material of the coil 901 is red copper tube.

[0047] The slit torsion member 2 is made of shape memory alloy material (SMA). According to the one-way memory effect of the shape memory alloy: the shape memory alloy deforms at a lower temperature and can recover its shape before deformation after heating and cooling. Due to this property, the deformed slit torsion member 2 can be heated to the transformation temperature to reach the austenite state, and the slit torsion member 2 will return to its initial undeformed state.

[0048] The outer wall 1 of the damper is provided singly or multiple times horizontally and / or vertically.

[0049] The working method of the above-mentioned SMA-based torsional amplification damper is as follows: under the action of horizontal wind or / and earthquake, when the building undergoes inter-story deformation, the displacement of the main structure of the building drives the connecting rod 8 connected thereto. The connecting rod 8 causes the steel sheet 6 to rotate. Through the rigid connection between the steel sheet 6 and the steel rod 5, the large gear 3 is driven to rotate. The large gear 3 drives three small gears 4 to rotate. During the rotation of the small gears 4, the slit torsion member 2 will be driven to twist; the heating device 9 causes the temperature of the slit torsion member 2 to rise rapidly. When the slit torsion member 2 reaches the transformation temperature and returns to its initial state, the reuse of the slit torsion member 2 can be easily realized.

[0050] The specific heating implementation is as follows: a heating coil 901 is wound around the surface of the slit torsion member 2 and there is a certain space reserved from the surface of the slit torsion member 2. The circuit is connected to form a heating device 9, which can be made of red copper tube. Through high-frequency large current, a strong magnetic flux will be generated inside the coil 901 to penetrate the entire slit torsion member 2, causing the temperature of the slit torsion member 2 to rise rapidly. When the slit torsion member 2 reaches the transformation temperature and returns to its initial state, the reuse of the slit torsion member 2 can be easily realized. At the same time, to prevent high temperature from affecting the performance of other components, heat-insulating asbestos (not shown) can be placed on the surface of the components that do not need to be heated but may be affected by the heating device to isolate the high temperature.

[0051] The above description of the embodiments is for the convenience of those of ordinary skill in the art to understand and use the invention. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative labor. Therefore, the present invention is not limited to the above embodiments, and the improvements and modifications made by those skilled in the art without departing from the scope of the present invention should be within the protection scope of the present invention.

Claims

1. An SMA-based torsional amplification damper, characterized in that, it includes a damper outer wall (1), a slit torsional member (2), a large gear (3), a small gear (4), a steel rod (5), a steel sheet (6), and a connecting rod (8); the damper outer wall (1) is fixedly connected to the main structure of the building; one side of the slit torsional member (2) is connected to the small gear (4), and the other side is connected to the damper outer wall (1); the large gear (3) meshes with the small gear (4); the steel sheet (6) is rigidly connected to the steel rod (5); the steel sheet (6) is connected to the connecting rod (8); the steel rod (5) is connected to the large gear (3); the SMA-based torsional amplification damper further includes a heating device (9); the heating device (9) is connected to the slit torsional member (2); the slit torsional member (2) is made of a shape memory alloy material; the heating device (9) includes an AC power supply (903), an overheat protection device (902), and a coil (901); the AC power supply (903), the overheat protection device (902), and the coil (901) are connected in series; the coil (901) is wound around the surface of the slit torsional member (2) and leaves a space on the surface of the slit torsional member (2); When inter-story deformation occurs in the building, the displacement of the main structure of the building drives the connecting rod (8) connected thereto. The connecting rod (8) causes the steel sheet (6) to rotate. Through the rigid connection between the steel sheet (6) and the steel rod (5), the large gear (3) is driven to rotate. The large gear (3) drives the small gear (4) to rotate. During the rotation of the small gear (4), the slit torsional member (2) is driven to twist; the heating device (9) causes the temperature of the slit torsional member (2) to rise. When the slit torsional member (2) reaches the jump temperature, it returns to its initial state, realizing the reuse of the slit torsional member (2).

2. The SMA-based torsional amplification damper according to claim 1, characterized in that, the material of the coil (901) is copper pipe.

3. The SMA-based torsional amplification damper according to claim 1, characterized in that, the SMA-based torsional amplification damper further includes a bolt (7); one side of the slit torsional member (2) is connected to the small gear (4) through the bolt (7), and the other side is connected to the damper outer wall (1) through the bolt (7).

4. The SMA-based torsional amplification damper according to claim 1, characterized in that, the damper outer wall (1) is a cuboid or cylindrical cavity welded by steel plates.

5. The SMA-based torsional amplification damper according to claim 4, characterized in that, the damper outer wall (1) is provided singly or multiple ones are provided horizontally and / or vertically.

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