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CN101446325A - Large-tonnage composite-structure magnetorheological damper - Google Patents

Large-tonnage composite-structure magnetorheological damper Download PDF

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Publication number
CN101446325A
CN101446325A CNA2008102429529A CN200810242952A CN101446325A CN 101446325 A CN101446325 A CN 101446325A CN A2008102429529 A CNA2008102429529 A CN A2008102429529A CN 200810242952 A CN200810242952 A CN 200810242952A CN 101446325 A CN101446325 A CN 101446325A
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China
Prior art keywords
damping
damper
magnetorheological
clay
cylinder
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杜成斌
于国军
李志全
孙立国
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Nanjing Hehai Technology Co Ltd
Hohai University HHU
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Nanjing Hehai Technology Co Ltd
Hohai University HHU
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Priority to CNA2008102429529A priority Critical patent/CN101446325A/en
Publication of CN101446325A publication Critical patent/CN101446325A/en
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Abstract

本发明公开了一种用于大型土木工程结构振动控制的大吨位复合结构磁流变阻尼器,它包括磁流变阻尼缸(9)、两个胶泥阻尼缸(5)、活塞(6)、活塞杆(17)、阻尼通道(16)、缸盖(3)、球形铰支关节(13)。在磁流变阻尼缸内充有磁流变液(11),并设置有可产生磁场的励磁线圈(8)。磁流变阻尼缸两侧设置了两个胶泥阻尼缸,其内腔充有弹性胶泥(7),可保证电源失效或能源不足时阻尼器能提供足够大阻尼力。解耦装置(18)的设置使磁流变阻尼器在低频域内具有高刚度、大阻尼,而在高频域内具有低刚度、小阻尼的特性。该阻尼器的最大出力较同尺寸传统磁流变阻尼器提高一倍以上,对大型土木工程结构的振动控制更为有效。

Figure 200810242952

The invention discloses a magneto-rheological damper with a large tonnage composite structure for vibration control of large-scale civil engineering structures, which comprises a magnetorheological damping cylinder (9), two clay damping cylinders (5), a piston (6), Piston rod (17), damping channel (16), cylinder head (3), spherical hinged joint (13). The magnetorheological damping cylinder is filled with magnetorheological fluid (11), and is provided with an excitation coil (8) capable of generating a magnetic field. Two clay damping cylinders are arranged on both sides of the magnetorheological damping cylinder, and the inner cavity thereof is filled with elastic clay (7), which can ensure that the damper can provide sufficient damping force when the power supply fails or the energy is insufficient. The setting of the decoupling device (18) enables the magneto-rheological damper to have high stiffness and large damping in the low frequency range, and low stiffness and small damping in the high frequency range. The maximum output of the damper is more than double that of the traditional magnetorheological damper of the same size, and it is more effective in controlling the vibration of large civil engineering structures.

Figure 200810242952

Description

Large-tonnage composite-structure magnetorheological damper
Technical field
The present invention relates generally to the damper field, is a kind of damper that is used for large scale civil engineering structure antidetonation (shaking), large-tonnage composite-structure magnetorheological damper especially a kind of highly energy-consuming of exerting oneself greatly and that damping-force adjustable can be provided.
Background technique
Strong earthquake has caused huge disaster to the people of other countries.In the earthquake considerable damage of building with collapse, be the immediate cause that causes earthquake disaster.China is one of country that earthquake disaster is the most serious in the world, and in about 450 cities, the whole nation, what be positioned at the seismic region accounts for 74.5%.In the big city of 28 1,000,000 above populations, have 85.7% to be positioned at the seismic region.And development along with national economy, the application of large scale civil engineering structure (mainly concentrating on important structure forms such as high building structure, towering construction structure, large span spatial structure, bridge structure, dam) is increasing at present, the material trend high-strength light that is adopted, this just makes, and the structure flexibility increases, damping descends, and is more responsive to wind-force and geological process.Be the integrity that guarantees structure and other requirement (as the travelling comfort of people in the building etc.), often will control carry the response that (as wind, earthquake etc.) cause outward by environment.So the antidetonation of relevant large scale civil engineering structure and vibration damping problem are more apparent outstanding, and by control mechanism is set on civil engineering structure, resist dynamic loads such as earthquake motion jointly by control mechanism and structure, the research of the structural vibration control that the dynamic response of structure reduces is had important practical significance.
Magnetic flow liquid (Magneto-rheological Fluid, be called for short MRF) be a kind of intellectual material of excellent performance, be called " controlled fluid " again, characteristics such as have the intensity height, viscosity is low, energy requirement is little, temperature stability is good, adding under the action of a magnetic field and can become shear yield stress higher Bingham plastomer or viscoelastic body by Newtonian fluid, and this transformation is continuous, reversible in the moment of Millisecond.Magnetic rheological liquid damper according to the magnetic rheology effect design is a kind of a new generation's half active drive device that is applicable to structural vibration control, have compact structure, low in energy consumption, advantage such as damping force is big, dynamic range is wide, speed of response is fast, its damping force can be controlled by the magnetic field size that adjusting adds, if cooperate certain control strategy, can make control structure reach vibration control effect preferably.
Viscoelasticity clay material is that a kind of high viscosity, organo-silicon compound flowable, uncured are the composite of matrix, has advantages of higher stability in-80 ℃ of-250 ℃ of temperature ranges, and odorless, nontoxic, and is pollution-free to environment and personnel.It is between the solid, liquid two states, utilize the damper of these characteristics design of clay material can not need return spring, utilize itself high elasticity characteristic just can realize the recovery backhaul of damper, its good flowability makes damper have big capacity, Low ESR ability simultaneously.The needs that the big I of the kinematic viscosity of clay material is used according to reality are adjusted, big dozens or even hundreds of times of its kinematic viscosity ratio normal hydraulic oil, and the damper sealing problem is simpler than hydraulic damper like this.The clay motion is continuously gapless, be little damping characteristic during little displacement, and show big damping characteristic during big displacement, so can guarantee in the vibration control process, can not influence the control efficiency of control system because of damping is excessive, having guaranteed simultaneously has enough dampings to absorb impact energy when generation is impacted in big displacement.These performances make it become the excellent materials of energy-dissipating and shock-absorbing.
The damper (energy comsuming device) of exploitation is to utilize single energy consume mechanism mostly both at home and abroad at present, and damping force that these dampers can provide and initial stiffness are all limited.Initial viscosity as magneto-rheological fluid is low, when the control system of magnetic rheological liquid damper breaks down and can not provide electric energy, the magnetic rheological liquid damper does not possess the damping regulatory function of common passive oil pressure damper, this moment, the magnetic rheological liquid damper did not just have due energy-dissipating and shock-absorbing effect for large scale civil engineering structure, its Security reduces greatly, and conventional MR damper is similar with common hydraulic damper, when dither, the rigidity hardening phenomenon can occur, be unfavorable for vibration damping control.And the damper that the energy dissipation behavior that utilizes the clay material is made singlely only possesses passive power consumption effect, can not realize real-time damping force control, and this vibration control effect for large scale civil engineering structure is limited.If arrange the vibration control that more damper (energy comsuming device) comes implementation structure in large scale structure, this can make troubles to construction, and improves engineering cost, and the usage space of influence building.
Summary of the invention
Technical problem:, the invention provides and a kind ofly can bring into play clay and two kinds of materials with different properties of magnetic flow liquid function admirable, cheap, simplicity of design, processing-installation-convenient disassembly, the large-tonnage composite-structure magnetorheological damper of damping performance brilliance of advantage separately at the technical problem that prior art exists.
Technological scheme: large-tonnage composite-structure magnetorheological damper of the present invention, comprise magnetorheological damping cylinder, two clay damped cylinders, sealing baffle, field coil, magnetic flow liquid, elastic cement, decoupling zero baffle plate, it is characterized in that magnetorheological damping cylinder two ends are respectively equipped with two clay damped cylinders, constitute the combination of three cylinders; Be filled with elastic cement in the clay damped cylinder, and be provided with elasticity decoupling zero device, this device is combined into by the elastic cement in piston, decoupling zero baffle plate and the two space.
Large scale civil engineering structure is when meeting with earthquake or wind load, structure can produce distortion, and be installed in large-tonnage composite-structure magnetorheological damper in the structure under suitable vibration control strategy, change magnetic intensity in the magnetorheological damping passage by the electric current that changes field coil, thereby change the damping force in the magnetorheological passage, form a kind of continuously adjustable semi-automatic control device.Meanwhile, relative displacement between the damper bearing makes the elastic cement in the clay damped cylinder produce the distortion of extruding hysteresis, the energy thereby consumption earthquake or wind shake, both collaborative works, structural vibration response is reduced, guarantee the safety of agent structure, and the safety guarantee mechanism of this clay damped cylinder damper when can be used as power-fail or energy deficiency.The setting of decoupling mechanism, improved the receptance of damper to energizing frequency and amplitude, and realized under different frequencies and amplitude, having distinct rigidity and damping characteristic, decoupling mechanism works when low frequency, large amplitude hardly, its performance is the clay damper and the combining of MR damper, and has big damping characteristic; And when high frequency, little amplitude, decoupling mechanism is in approximate decoupling zero state, and damper has the characteristic of little damping, low dynamic stiffness, can reduce the high frequency transmissibility.Rational Match by MR damper and clay damper be connected, the exploitation large-tonnage composite-structure magnetorheological damper can satisfy the antidetonation wind resistance needs of large scale civil engineering structure, damping effect is remarkable.
Compared with prior art, the present invention has the following advantages:
1, the present invention adopts magnetorheological half ACTIVE CONTROL and two kinds of machine-processed synergistic combination vibration dampings of the passive power consumption of clay, have that damping performance is good, cheap, the advantage of simplicity of design, processing-installation-convenient disassembly, and the size of each main member, gap can freely be adjusted according to actual requirement of engineering;
2, when identical damping force is provided, large-tonnage composite-structure magnetorheological damper of the present invention is compared with simple MR damper, the shortcoming that damper forfeiture regulatory function, controlled safety of structure reduce when having overcome power-fail or energy deficiency, and has an energy saving, improve damping force, reduce the advantage of damper cost of production; Compare with simple clay damper, it has, and damping force is adjustable continuously, adaptability strong, the even more ideal advantage of control effect; Compare with the MR damper of common permanent magnetism+coil magnetization combination, its structural type is more simple, and rate of fault is low, price is also cheaper;
3, the elastic cement of Cai Yonging is a kind of known high-compressibility, high viscosity, flowable semisolid viscous medium, viscosity can reach 500,000 centipoises, compressibility can reach 30%, in than large-temperature range, be suitable for and performance constant substantially, to have a volume little for the clay damper of Zhi Zuoing thus, damping force is big, the advantage that S. E. A. is high;
4, the present invention has decoupling-structure, rigidity hardening phenomenon when having overcome dither, it is all very sensitive to energizing frequency and amplitude, under different frequencies and amplitude, have distinct rigidity and damping characteristic, in lower frequency region, have high rigidity, big damping, and in high-frequency domain, have the characteristic of low rigidity, little damping;
5, the two ends of magnetorheological damping cylinder are provided with the clay damped cylinder, can effectively prevent the seepage of magnetic flow liquid, and durability is good.
Utilize two kinds of machine-processed combined shock absorptions of magnetic current and liquid flow variation characteristic and clay shear extrusion hysteresis distortion, brought into play the advantage of two kinds of shock absorbing mechanisms, both had very high energy dissipation capacity, can provide continuously adjustable damping force again.Being provided with of its decoupling-structure improved the ability of structure opposing external force, more helps improving the effect of large scale structure vibration control.This damper can be widely used in the wind resistance earthquake proof construction of large scale civil engineering structure.
Description of drawings
Fig. 1 is a structural representation of the present invention;
Fig. 2 is the decoupling-structure schematic representation.
Among the figure:
1-bearing 12-fixing bolt
The spherical hinged joint of 2-lead 13-
3-cylinder cap 14-lead channels
4-sealing guiding device 15-O RunddichtringO
5-clay damped cylinder 16-magnetorheological damping passage
6-piston 17-piston rod
7-elastic cement 18-decoupling zero baffle plate
The secondary cylinder of 8-field coil 19-
9-magnetorheological damping cylinder 20-sealing baffle
10-is every magnetic sheath 21-liquid filling hole
11-magnetic flow liquid 22-injecting glue mud hole
Embodiment
Below in conjunction with accompanying drawing the present invention is described in further details.
Large-tonnage composite-structure magnetorheological damper of the present invention as shown in Figure 1, it comprises magnetorheological damping cylinder (9), two clay damped cylinders (5), sealing baffle (20), field coil (8), magnetic flow liquid (11), elastic cement (7), decoupling zero baffle plate (18).It is characterized in that this device is connected with clay damped cylinder (5) respectively at the two ends of magnetorheological damping cylinder, in MR damper clutch release slave cylinder (9), be full of magnetic flow liquid (11), arrange field coil (8) on this piston, field coil (8) outer wrapping is every magnetic sheath (10), and piston told three magnetic poles, lead (2) connects field coil and external power supply by lead channels (14); Two clay damped cylinders (5) lay respectively at magnetorheological damping cylinder (9) two ends, in clay damped cylinder (5), be full of elastic cement (7), clay damped cylinder (5) two ends are respectively sealing baffle (20) and sealing guiding device (4), be provided with decoupling zero device (18) between this piston (6) and the piston rod (17), its space is filled with elastic cement (7), and left and right sides two-part of piston (6) connect by fixing bolt (12); Piston rod (17) left end in the magnetorheological damping cylinder (9) passes sealing baffle (20), clay damped cylinder (5), sealing guiding device (4) and is connected with spherical hinged joint (13), and freedom was overhanging in secondary cylinder (19) after piston rod (17) right-hand member in the magnetorheological damping cylinder (9) passed sealing baffle (20), clay damped cylinder (5), sealing guiding device (4); The right-hand member cylinder cap is connected with the spherical hinged joint of right-hand member (13), and the spherical hinged joint (13) at two ends is wrapped up by bearing (1) respectively.On magnetorheological damping cylinder (9), be provided with magnetic flow liquid liquid filling hole (21), on clay damped cylinder (5), be provided with injecting glue mud hole (22).Sealing baffle (20), sealing guiding device (4), every between magnetic sheath (10) and the magnetic conduction piston, piston rod (17) and have between the piston of field coil and be equipped with O RunddichtringO (15).
Between magnetorheological damping cylinder and field coil, there is the damper passage, be generally 0.6~2mm, the magnetic flow liquid that can push during back and forth movement in clutch release slave cylinder in the magnetorheological damping cylinder when piston flows in damp channel, when field coil feeds electric current, with the magnetic field that produces perpendicular to fluid flow direction, the magnetic flow liquid semi-solid preparation, the resistance of fluid increases, and realizes the suitable continuously contrary adjustable of magnetorheological damping power by changing size of current.In the clay damper, there is damp channel between clay damped cylinder and the piston, be generally 2~9mm, elastic cement in the back and forth movement meeting squeezed air-damping cylinder of piston in the clay damped cylinder, make its volume shrinkage, and in the damping gap, flow, thereby produce bigger damping force, consume vibrational energy.Decoupling mechanism is to have the gap between decoupling zero baffle plate on the piston rod and the piston on the piston rod in the clay damped cylinder, and in the gap, be full of elastic cement, elastic cement is volume-diminished by compression the time, when not being subjected to external force, automatically reset again, such decoupling zero device works when low frequency, large amplitude hardly, its performance is the clay damper and the combining of MR damper, and has big damping characteristic; And when high frequency, little amplitude, decoupling mechanism is in approximate decoupling zero state, and damper has the characteristic of little damping, low rigidity, can reduce the high frequency transmissibility.
The damping force of large-tonnage composite-structure magnetorheological damper of the present invention is that the damping force two-part by MR damper and clay damper combine, can select the different values of exerting oneself according to the concrete structure actual demand, the damping force of MR damper is generally 0~500kN, input current is generally 0~5A, and the damping force of clay damper is generally 0~2000kN.In concrete large-scale civil structure engineering, take all factors into consideration structural seismic demand and the characteristic of itself, the structural type (comprising clay kind, piston diameter, piston thickness, damping gap, stroke etc.) of structural type of appropriate design MR damper (comprising the diameter of magnetorheological maximum shear yield strength, coil turn, magnet case material, NULL, magnetic pole number, damp channel effective length, damping gap, stroke, piston and piston rod etc.) and clay damper is to reach desirable vibration control effect.

Claims (3)

1、一种大吨位复合结构磁流变阻尼器,它包括磁流变阻尼缸(9)、两个胶泥阻尼缸(5)、密封挡板(20)、励磁线圈(8)、磁流变液(11)、弹性胶泥(7)、解耦挡板(18),其特征在于磁流变阻尼缸(9)与两个胶泥阻尼缸(5)构成三缸组合,在胶泥阻尼缸(5)内设有弹性解耦装置。1. A magnetorheological damper with a large tonnage composite structure, which includes a magnetorheological damping cylinder (9), two cement damping cylinders (5), a sealing baffle (20), an excitation coil (8), a magnetorheological Liquid (11), elastic clay (7), decoupling baffle (18), characterized in that the magnetorheological damping cylinder (9) and two clay damping cylinders (5) form a three-cylinder combination, and the clay damping cylinder (5 ) is equipped with an elastic decoupling device. 2、根据权利要求1所述的大吨位复合结构磁流变阻尼器,其特征在于:两个胶泥阻尼缸(5)分别位于磁流变阻尼缸(9)的两侧。2. The magnetorheological damper with large tonnage composite structure according to claim 1, characterized in that: two cement damping cylinders (5) are respectively located on both sides of the magnetorheological damping cylinder (9). 3、根据权利要求1所述的大吨位复合结构磁流变阻尼器,其特征在于:弹性解耦装置由活塞(6)、解耦挡板(18)与二者空隙中的弹性胶泥(7)组合成。3. The magnetorheological damper with large tonnage composite structure according to claim 1, characterized in that: the elastic decoupling device is composed of the piston (6), the decoupling baffle (18) and the elastic cement (7) in the gap between the two )combined to.
CNA2008102429529A 2008-12-30 2008-12-30 Large-tonnage composite-structure magnetorheological damper Pending CN101446325A (en)

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101793302A (en) * 2010-03-18 2010-08-04 河海大学 Three-cylinder type large-capacity magneto-rheological damper
CN102278409A (en) * 2011-05-20 2011-12-14 宁波大学 Piston-type double-coil magnetorheological damper
CN103290943A (en) * 2013-05-30 2013-09-11 河海大学 Multipurpose initiative controllable large-output vibration insulating and damping device
CN104832587A (en) * 2015-05-20 2015-08-12 武汉理工大学 Container crane magneto-rheological intelligent damping device
CN106286686A (en) * 2016-10-28 2017-01-04 合肥工业大学 A kind of automotive self-adaptive collision energy-absorbing system
CN106402254A (en) * 2016-11-18 2017-02-15 合肥工业大学 Inner by-pass valve type magnetorheological fluid suspension
CN106594159A (en) * 2016-12-16 2017-04-26 合肥工业大学 Magnetorheological composite suspension capable of achieving three-direction vibration isolation
CN111042367A (en) * 2019-11-21 2020-04-21 河海大学 A composite magnetron squeeze damper with double special-shaped pistons
CN111973405A (en) * 2020-07-09 2020-11-24 中国科学院深圳先进技术研究院 Leg exoskeleton device and control method thereof

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101793302A (en) * 2010-03-18 2010-08-04 河海大学 Three-cylinder type large-capacity magneto-rheological damper
CN102278409A (en) * 2011-05-20 2011-12-14 宁波大学 Piston-type double-coil magnetorheological damper
CN103290943A (en) * 2013-05-30 2013-09-11 河海大学 Multipurpose initiative controllable large-output vibration insulating and damping device
CN103290943B (en) * 2013-05-30 2015-06-17 河海大学 Multipurpose initiative controllable large-output vibration insulating and damping device
CN104832587A (en) * 2015-05-20 2015-08-12 武汉理工大学 Container crane magneto-rheological intelligent damping device
CN106286686A (en) * 2016-10-28 2017-01-04 合肥工业大学 A kind of automotive self-adaptive collision energy-absorbing system
CN106402254A (en) * 2016-11-18 2017-02-15 合肥工业大学 Inner by-pass valve type magnetorheological fluid suspension
CN106402254B (en) * 2016-11-18 2018-05-01 合肥工业大学 A kind of valve type magneto-rheological fluid suspension of internal bypass road
CN106594159A (en) * 2016-12-16 2017-04-26 合肥工业大学 Magnetorheological composite suspension capable of achieving three-direction vibration isolation
CN106594159B (en) * 2016-12-16 2019-05-31 合肥工业大学 A kind of magneto-rheological combined suspension for realizing three-dimensional vibration isolation
CN111042367A (en) * 2019-11-21 2020-04-21 河海大学 A composite magnetron squeeze damper with double special-shaped pistons
CN111973405A (en) * 2020-07-09 2020-11-24 中国科学院深圳先进技术研究院 Leg exoskeleton device and control method thereof

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