CN216786795U

CN216786795U - Vertical nonlinear eddy current tuned mass damper with damping amplification characteristic

Info

Publication number: CN216786795U
Application number: CN202123153642.XU
Authority: CN
Inventors: 欧阳郁汀; 施竹珺
Original assignee: Shanghai Rb Vibration Science And Technology Co ltd
Current assignee: Shanghai Rb Vibration Science And Technology Co ltd
Priority date: 2021-12-07
Filing date: 2021-12-07
Publication date: 2022-06-21
Anticipated expiration: 2031-12-07

Abstract

The utility model relates to a vertical nonlinear eddy current tuned mass damper with damping amplification characteristics, which comprises a steel plate base, wherein a plurality of groups of square stiffness nonlinear springs are fixed above the steel plate base, mass blocks are arranged on the springs, and two eddy current damping devices are fixed in front of and behind the mass blocks. The eddy current damping device comprises an コ -shaped shell and a lever structure, wherein two parallel magnets are fixed on the inner wall of the コ -shaped shell, a copper plate is fixed at the left end of the lever structure and inserted into a gap between the two magnets, and the copper plate is enabled to do motion of cutting magnetic lines along with the up-and-down swing of the lever structure. In the utility model, an eddy current energy consumption mechanism is realized by utilizing an electromagnetic induction principle, a damping device of a permanent magnet-conductor plate is adopted to provide damping force, and external energy supply is not needed; the eddy current energy dissipation damping force is amplified through the lever structure, and under the condition that damping parameters are determined, a small magnet and a small copper plate can be selected to meet design requirements.

Description

Vertical nonlinear eddy current tuned mass damper with damping amplification characteristic

Technical Field

The utility model relates to the technical field of civil engineering structure control, in particular to a vertical nonlinear eddy current tuned mass damper with damping amplification characteristics.

Background

In order to meet the increasing architectural aesthetic design requirements and functional use requirements, the modern civil engineering structure design trend gradually develops towards large span, softness, high rise and the like. The light structure model reduces the structural rigidity, so that the structure generates larger structural vibration under the low-frequency excitation action of wind load or pedestrian load and the like.

In daily life, a common structure is a pedestrian overpass, and because the structure system is flexible, the natural vibration frequency is generally close to the walking step frequency of people, about 0.5Hz to 2.8Hz, and therefore vibration control in the vertical direction and the horizontal direction of the cross section of the overpass structure is needed. The dynamic vibration absorption technology is an effective means for vibration control, and in order to realize vibration control on a soft structure, the traditional technical means is to structurally mount a tuned mass damping vibration attenuation device.

Currently, common tuned mass damping vibration dampers include support dampers and pendulum dampers: the supporting type damper supports the mass block through the vertical spring to realize the vibration suppression of the controlled structure; the pendulum damper realizes the vibration suppression of a controlled structure by suspending a mass block on a suspension rod. However, in both the support type damper and the pendulum type damper, the eddy current damper has a relatively low damping coefficient, and thus it is difficult to satisfy the damping force required by the large civil engineering structure.

SUMMERY OF THE UTILITY MODEL

In order to overcome the problems, the utility model provides a vertical nonlinear eddy current tuned mass damper with damping amplification characteristics.

The technical scheme adopted by the utility model for solving the technical problems is as follows:

the tuned mass damper comprises a steel plate base, wherein a plurality of groups of square stiffness nonlinear springs are fixed above the steel plate base, mass blocks are arranged on the square stiffness nonlinear springs, and two eddy current damping devices which are symmetrical with respect to the center of gravity of the mass blocks are fixed in the front and at the back of the mass blocks. The eddy current damping device comprises an コ -shaped shell and a lever structure which are fixed on the side surface of the mass block, wherein two parallel magnets with gaps left in the middle are fixed on the inner wall of the コ -shaped shell, a copper plate is fixed at the left end of the lever structure through a fixing piece, the copper plate is inserted into the gaps of the two magnets, the polarities of the magnets on the two sides of the copper plate are opposite, and the copper plate is made to move along with the upward and downward swinging of the lever structure to cut magnetic lines of force.

Furthermore, the lever structure comprises a positioning pin with one end fixed on the mass block and a lever rotatably connected with the other end of the positioning pin.

Further, the copper plate with the lever passes through mounting fixed connection, just the copper plate is located the lever is kept away from the one end of dowel.

Furthermore, a rolling bearing is embedded in a lever of the lever structure, and two ends of the positioning pin are respectively tightly matched with the rolling bearing and the mass block, so that the lever rotates by taking the positioning pin as a fulcrum.

Furthermore, a positioning support is additionally arranged on the steel plate base, and a baffle is fixed at the top end of the positioning support.

Preferably, the locating support is a steel bar with a circular cross section, the steel plate base and the baffle are both provided with round holes, and the upper end and the lower end of the locating support are fixed with the baffle and the steel plate base respectively in a perforation plug welding mode.

Preferably, the lower surface of the baffle plate is in contact with the upper surface of the right end of the lever so as to ensure that the copper plate is always in the magnetic field.

Furthermore, the cubic stiffness nonlinear spring, the mass block and the steel plate base are connected in a fastener mode.

Preferably, the number of the cubic stiffness nonlinear springs is four.

Compared with the prior art, the beneficial effect of adopting the above technical scheme is:

(1) an eddy current energy consumption mechanism is realized by utilizing an electromagnetic induction principle, and meanwhile, a damping device of a permanent magnet-conductor plate is adopted to provide damping force without externally providing energy;

(2) the cubic stiffness nonlinear spring is adopted, so that the tuned mass damper has different frequencies under different spring deformations, and the problem of poor low damping robustness is solved;

(3) the amplification of eddy current energy dissipation damping force is realized through a lever structure, and under the condition that the damping parameters of the tuned mass damper are determined, a smaller magnet and a smaller copper plate can be selected to meet the design requirements;

(4) simple structure, easy installation and good durability.

Drawings

The drawings, in which like reference numerals refer to like parts, are for the purpose of illustrating particular embodiments only and are not to be construed as limiting the utility model.

Fig. 1 is a front view of the present invention.

Fig. 2 is a top view of the present invention.

In the figure:

1-mass block, 2-cubic stiffness nonlinear spring, 3-steel plate base and 4-eddy current damping device;

41- "コ" type shell, 42-magnet, 43-copper plate, 44-fastener, 45-lever structure; 451-lever, 452-rolling bearing, 453-locating pin, 454-baffle, 455-locating support.

Detailed Description

The technical solution of the present invention is further described in detail with specific embodiments in the following with reference to the accompanying drawings. It should be understood that the following examples are illustrative only and are not intended to limit the scope of the present invention.

In the embodiment of the utility model, the fixing mode can adopt welding and bolt connection according to the design, processing or construction requirements, and can be direct connection or indirect connection through an intermediate conversion device. The fixing means given here are only examples and the meaning of the fixing means in the present invention can be understood by those skilled in the art as the case may be.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on those shown in fig. 1, and are only for convenience of description and simplicity of description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.

Referring to fig. 1 and 2, the tuned mass damper with damping amplification characteristic for vertical nonlinear eddy currents according to the present invention includes a steel plate base 3, a plurality of sets of cubic stiffness nonlinear springs 2 are fixed above the steel plate base 3, a mass block 1 is disposed on the cubic stiffness nonlinear springs 2, and two eddy current damping devices 4 are fixed to the front and back of the mass block 1 and are symmetric with respect to the center of gravity of the mass block 1. The eddy current damping device 4 comprises an コ -shaped shell 41 fixed on the side surface of the mass block 1 and a lever structure 45, wherein two parallel magnets 42 with enough gap are fixed on the inner wall of the コ -shaped shell 41, and the lever structure 45 comprises a positioning pin 453 fixed on the mass block 1 at one end and a lever 451 rotatably connected with the other end of the positioning pin 453. The left end of the lever structure 45 is fixed with a copper plate 43 through a fixing member 44, such as a bolt, the copper plate 43 is inserted into the gap between the two magnets 42, and the polarities of the magnets on the two sides of the copper plate 43 are opposite, so that the copper plate 43 can perform magnetic line cutting motion along with the up-and-down swing of the lever structure 45, and thus an eddy current is generated and eddy current damping is generated.

Further, the number of the cubic stiffness nonlinear springs 2 is preferably four.

Further, the copper plate 43 is fixedly connected to the lever 451 by the fixing member 44, such as a bolt, and the copper plate 43 is located at an end of the lever 451 away from the positioning pin 453.

Furthermore, a rolling bearing 452 is embedded in the lever 451, and two ends of the positioning pin 453 are respectively tightly matched with the rolling bearing 452 and the mass block 1, so that the lever 451 rotates by taking the positioning pin 453 as a fulcrum.

Furthermore, a positioning support 455 may be added to the steel plate base 3, and a baffle 454 is fixed to the top end of the positioning support 455.

Preferably, the positioning support 455 is a steel bar with a circular cross section, the steel plate base 3 and the baffle 454 are both provided with round holes (not shown in the figure), and the upper end and the lower end of the positioning support 455 are fixed to the baffle 454 and the steel plate base 3 by means of through-hole plug welding.

Preferably, the lower surface of the baffle 454 contacts the upper surface of the right end of the lever 451, thereby limiting the rotation amplitude of the lever 451 to ensure that the copper plate 43 is always within the magnetic field.

Further, the cubic stiffness nonlinear spring 2, the mass block 1 and the steel plate base 3 are connected by fasteners.

The working principle is as follows: when the non-magnetic conductor, i.e. the copper plate 43, makes a magnetic line-cutting motion in the magnetic field formed by the two magnets 42, the magnetic flux passing through the copper plate 43 continuously changes, and according to the faraday's law of electromagnetic induction, a corresponding induced electromotive force is generated in the copper plate 43, thereby forming a current similar to a vortex, i.e. a so-called eddy current. According to lenz's law, the eddy current will simultaneously generate a new magnetic field opposite to the original magnetic field, so as to form a damping force for preventing the copper plate 43 from cutting the magnetic lines of force in the magnetic field, and the structure circulated in this way finally results in that the vibration energy is consumed by the resistance thermal effect of the conductor, which is called eddy current damping.

In the embodiment of the utility model, when the structure vibrates, the vibration is transmitted to the mass block 1 through the steel plate base 3 and the cubic stiffness nonlinear spring 2, and the mass block 1 is in a resonance or quasi-resonance state. The maximum stroke of the mass block 1 is determined according to design parameters of the tuned mass damper and the allowable design vibration amplitude of the structure, the amplification factor of the lever 451 in the damping system is determined by designing the distance between the axis of the positioning pin 453 and the left end and the right end of the lever 451, the amplification ratio of the lever 451 is recorded as mu, and then the maximum speed of the copper plate 43 at the left end of the lever 451 is mu times of the maximum movement speed of the mass block. Under the condition that the damping parameters of the tuned mass damper are determined, a smaller magnet and a smaller copper plate can be selected to meet the design requirements. In addition, the nonlinear spring with cubic stiffness enables the tuned mass damper to have different frequencies under different spring deformations, and the design also solves the problem of poor low damping robustness, so that the tuned mass damper can well control the vertical vibration of a broadband.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and amendments can be made without departing from the principle of the present invention, and these modifications and amendments should also be considered as the protection scope of the present invention.

Claims

1. A vertical nonlinear eddy current tuned mass damper with damping amplification characteristics comprises a steel plate base (3), wherein a plurality of groups of square stiffness nonlinear springs (2) are fixed above the steel plate base (3), and a mass block (1) is arranged on each of the square stiffness nonlinear springs (2), and is characterized in that two eddy current damping devices (4) which are symmetrical with respect to the center of gravity of the mass block (1) are fixed to the front and the back of the mass block (1), and each eddy current damping device (4) comprises an コ -shaped shell (41) and a lever structure (45) which are fixed on the side surface of the mass block (1); the inner wall of the コ -shaped shell (41) is fixed with two parallel magnets (42) with a gap in the middle, the left end of the lever structure (45) is fixed with a copper plate (43) through a fixing piece (44), the copper plate (43) is inserted into the gap between the two magnets (42), and the polarities of the magnets on the two sides of the copper plate (43) are opposite, so that the copper plate (43) can do magnetic line cutting motion along with the up-and-down swinging of the lever structure (45).

2. The eddy current tuned mass damper according to claim 1, characterized in that the lever structure (45) comprises a dowel pin (453) fixed at one end to the mass (1) and a lever (451) rotatably connected to the other end of the dowel pin (453).

3. The eddy current tuned mass damper according to claim 2, characterized in that the copper plate (43) is fixedly connected with the lever (451) by means of the fixing element (44), and the copper plate (43) is located at the end of the lever (451) remote from the locating pin (453).

4. The tuned mass damper of eddy current according to claim 2, characterized in that a rolling bearing (452) is embedded in the lever (451) of the lever structure (45), and the two ends of the positioning pin (453) are respectively tightly fitted with the rolling bearing (452) and the mass block (1) so that the lever (451) rotates around the positioning pin (453) as a fulcrum.

5. The tuned mass damper of eddy currents according to claim 2, characterized in that a positioning support (455) is added to said steel plate base (3), and a baffle (454) is fixed to the top end of said positioning support (455).

6. The tuned mass damper of eddy current according to claim 5, wherein the positioning support (455) is a steel bar with a circular cross section, the steel plate base (3) and the baffle plate (454) are both provided with circular holes, and the upper end and the lower end of the positioning support (455) are respectively fixed with the baffle plate (454) and the steel plate base (3) by means of plug welding through holes.

7. The eddy current tuned mass damper according to claim 5, characterized in that the lower surface of the baffle (454) is in contact with the upper surface of the right end of the lever (451) to ensure that the copper plate (43) is always within the magnetic field.

8. The tuned mass damper according to claim 1, wherein the cubic stiffness nonlinear spring (2) and the mass (1) are connected to the steel plate base (3) by means of fasteners.

9. The eddy current tuned mass damper according to claim 1, characterized in that the number of cubic stiffness nonlinear springs (2) is four groups.