CN115978131A - A Parameter Continuously Adjustable Self-resetting Eddy Current Inertial Mass Damper for Model Stayed Cable Vibration Test - Google Patents

Abstract

The invention provides a parameter continuously adjustable self-resetting electric eddy current inertial mass damper for the model cable-stayed cable vibration-reduction test, which is applied to the model cable-stayed cable vibration-reduction test, including a damper frame, a ball screw mechanism, a mass Flywheel and conductor plate, one end of the ball screw mechanism is connected with the model stay cable, and the other end is connected with the conductor plate. The ball screw mechanism and the conductor plate are respectively arranged inside the damper frame, and the upper side of the damper frame is provided with a linear bearing and a supporting spring, and the supporting spring realizes the self-resetting function of the damper. The ball nut of the ball screw mechanism is equipped with a mass flywheel to adjust the inertial mass; the damper frame is equipped with an electromagnet to generate an electromagnetic field; the conductor plate moves between the electromagnets and then cuts the electromagnetic field to generate equivalent damping force, changing the power supply current of the electromagnet Used to adjust the damping coefficient. The invention can continuously adjust the inertial mass and the damping coefficient with high precision, and alleviates the technical problems existing in the existing model cable-stayed vibration damping test.

Description

A Parameter Continuously Adjustable Self-resetting Eddy Current Inertial Mass Damper for Model Stayed Cable Vibration Test

technical field

The invention relates to the technical field of building vibrations such as civil engineering and transportation, and in particular to a parameter-continuously adjustable self-resetting eddy current inertial mass damper for model cable-stayed vibration reduction tests.

Background technique

A damper is a device that provides motion resistance and dissipates motion energy. Because of its energy-absorbing and vibration-reducing effects, it is widely used in industries such as aerospace, aviation, military industry, guns and automobiles. Since the 1970s, researchers have gradually applied dampers to structural engineering fields such as buildings, bridges, and railways. For example, it is a common way to use external dampers in cable-stayed vibration control projects.

As a commonly used support structure in the field of civil and transportation structural engineering, cables have the disadvantages of large flexibility, small damping, and low frequency. Therefore, they are prone to large vibrations under external excitation, such as wind and rain vibration, vortex induced vibration, etc. Moreover, with the increase of the design length of the cable stay, the traditional passive viscous damper can no longer meet the current vibration control requirements of the cable stay. The passive damper with negative stiffness characteristics has attracted extensive attention and research from scholars because of its high-efficiency damping effect. Among them, the inertial mass damper is a new type of passive damper with negative stiffness characteristics. Research shows that its energy dissipation capacity far exceeds that of traditional viscous dampers. However, most of the current research on inertial mass dampers is in the stage of theoretical simulation. Therefore, whether the damping effect of stay cables is efficient remains to be verified by experiments.

The scale test is an important research method to verify the theoretical hypothesis, and it can effectively verify whether the vibration reduction effect of the inertial mass damper on the stay cable is consistent with the theory. In the scale test, it is often necessary to perform high-precision testing of the damper parameters. Continuous adjustment, otherwise the experimental results obtained will easily have large errors with the theoretical results, and it will also make it difficult to analyze the cause of the errors. At present, the adjustment method of the inertial mass of the scale test inertial mass damper is mainly to replace the mass flywheel with different mass or size, such as the patent literature "an electric eddy current inertial mass damper" (application publication number: CN111321820A) and "a Parameter-adjustable inertial mass damper for model cable-stayed vibration reduction test" (application publication number: CN108662072A), etc. The adjustment method of the damping coefficient of the inertial mass damper includes changing the number, size, air gap and arrangement of the permanent magnets, such as the patent document "A Rack and Pinion Type Inertia Eddy Current Damper" (CN115539545A); Viscous damping fluids with different viscosity coefficients, such as the patent document "A Parameter-Adjustable Inertial Mass Damper for Vibration Reduction Tests of Model Stayed Cables" (Application Publication No.: CN108662072A) and the like.

However, none of the above damper parameter adjustment methods can truly achieve high-precision continuous adjustment. Changing the mass or size of the mass flywheel cannot guarantee the continuity of the inertial mass test parameters; changing the size, quantity and arrangement of permanent magnets, or using viscous damping fluids with different viscosity coefficients not only cannot guarantee the continuity of the damping coefficient test parameters, It will also bring complicated operation procedures to the test and there are hidden dangers of test accidents.

Contents of the invention

In order to solve the above problems, the present invention provides a dual-parameter continuous adjustable self-resetting eddy current inertial mass damper for inertial mass and damping coefficient used in model cable-stayed vibration damping tests, which can be used for models of multiple working conditions The cable vibration damping test solves the problem that the existing parameters cannot be adjusted continuously with high precision, and provides an effective means for verifying the vibration damping effect of the inertial mass damper. For this reason, the present invention adopts following technical scheme:

A parameter-continuously adjustable self-resetting electric eddy current inertial mass damper for vibration reduction tests of model cables, characterized in that it includes a damper frame, a ball screw mechanism, a quality flywheel, a conductor plate, an electromagnet and a linear bearing ;

One end of the screw rod in the ball screw mechanism is connected with the model cable, and the other end is connected with the conductor plate; the ball nut in the ball screw mechanism and the conductor plate are arranged in the damper frame, and the The ball nut is positioned axially;

The electromagnet is fixed on both sides of the damper frame, the conductor plate is located in the magnetic field generated by the electromagnet, and the reciprocating motion of the conductor plate can cut the magnetic field lines; the linear bearing is arranged on the upper side of the damper frame;

The mass flywheel includes a drum, spokes and counterweights; the spokes are equally spaced on the drum; the counterweights are arranged on the spokes in a detachable or/and adjustable axial position ; The quality flywheel is set on the outside of the ball nut.

Further, the ball screw mechanism includes a screw, a ball nut and a thrust bearing for axially positioning the roller nut.

Further, the counterweight can slide axially along the spokes, so as to change the moment of inertia of the mass flywheel, so as to achieve the purpose of adjusting the inertial mass; in the ball screw mechanism, only the screw follows The vibration of the model stay cable produces axial linear motion and drives the conductor plate to linear motion, and both the ball nut and the mass flywheel undergo rotational motion.

Further, the upper end of the conductor plate is equipped with a linear optical axis, and the lower end is connected to the screw; the linear optical axis passes through the linear bearing; the part of the linear optical axis passing through the linear bearing is covered with a support Spring; the end of the linear optical axis is equipped with a spring baffle; the support spring is limited on the linear optical axis by the spring baffle; the conductor plate is only limited by the screw and the linear bearing In-plane linear motion occurs; the conductor plate cannot undergo out-of-plane rotational motion under the restriction of the support spring and the spring baffle.

Further, its movable part includes the screw rod, the conductor plate, the optical axis and the spring baffle, and the weight of the movable part is borne by the supporting spring; under the action of the supporting spring Next, the model stay cable will not produce initial deformation due to the weight of the movable part of the damper, which reduces the experimental error of the model stay cable vibration test; under the action of the support spring, each time the model is inclined After the cable vibration test, the model cable and the movable part will return to the initial equilibrium position to realize the self-resetting function.

Further, electromagnets are arranged on opposite sides of the damper frame; the north and south poles of the electromagnets are arranged opposite to each other; the electromagnets generate an electromagnetic field through external power supply; the strength of the electromagnetic field can be adjusted by adjusting the magnitude of the power supply current; the The movement of the conductor in the electromagnetic field produces an equivalent viscous damping force, and the damping coefficient can be adjusted by changing the supply current of the electromagnet.

The present invention can continuously adjust the inertial mass and damping coefficient with high precision, can be used in multi-working condition model cable vibration damping tests, solves the problem that the existing parameters cannot be adjusted continuously with high precision, and provides a means for verifying the vibration damping effect of the inertial mass damper effective means.

Description of drawings

Fig. 1 is an overall schematic diagram of an embodiment of the present invention.

Fig. 2 is a schematic diagram of the frame of the damper according to the embodiment of the present invention.

Fig. 3 is a schematic diagram of a ball screw mechanism according to an embodiment of the present invention.

Fig. 4 is a schematic diagram of a mass flywheel according to an embodiment of the present invention.

Fig. 5 is a schematic diagram of a conductor plate according to an embodiment of the present invention.

Fig. 6 is a schematic diagram of a model cable-stayed vibration damping test.

Explanation of main component labels: 1: Damper frame frame 1; 2: Damper frame frame 2; 3: Electromagnet; 4: Electromagnet fixing chamber; 5: Damper frame; 6: Linear bearing; 7: Support spring ;8: spring baffle; 9: ball screw; 10: thrust bearing; 11: ball nut; 12: drum; 13: spoke; 14: counterweight; 15: conductor plate; 16: linear optical axis, model Stay cable 17, damper 18.

Detailed ways

The technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Apparently, the described embodiments are some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "inside", "outside", "upper side", "lower side", "both sides", "straight line" and so on are based on the drawings The orientations or positional relationships shown are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as an important aspect of the present invention. limits. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and should not be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "connection", "connection" and "setting" should be understood in a broad sense, for example, it can be a fixed connection, or It can be a detachable connection or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediary, and it can be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention in specific situations.

It should be noted that like numerals and letters denote similar items in the following figures, therefore, once an item is defined in one figure, it does not require further definition and explanation in subsequent figures.

The present invention provides a parameter continuously adjustable self-resetting eddy current inertial mass damper for the model cable-stayed vibration reduction test, as shown in Figures 1 to 5, comprising an electromagnet 3, an electromagnet fixing chamber 4, a damping Device frame 5, linear bearing 6, support spring 7, spring baffle 8, ball screw 9, thrust bearing 10, ball nut 11, wheel drum 12, spoke 13, counterweight 14, conductor plate 15, linear optical axis 16 , model stay cable 17, damper 18.

Damper frame 5 is made up of frame body one 1 that is positioned at frame body two 2 and frame body two 2 lower ends.

As shown in the figure, the lower end of the damper 18 provided by the present invention is connected with the model stay cable 17 through the ball screw 9; sensors can also be added between the ball screw 9 and the model stay cable 17 to test data such as damping force, damper displacement To measure and record; the upper end of the ball screw 9 is connected to the conductor plate 15; the drum 12 of the mass flywheel is set outside the ball nut 11; the spokes 13 of the mass flywheel are installed outside the drum 12; the counterweight 14 of the mass flywheel is arranged on the spokes 13; the ball nut 11 is placed inside the frame body 1 of the damper frame; the upper and lower sides of the ball nut 11 are respectively provided with thrust bearings 10; the electromagnet 3 is fixed to the two sides of the frame body 2 of the damper frame by bolts The electromagnet fixed bin 4 is used to generate an electromagnetic field; the conductor plate 15 is arranged inside the frame body 2 of the damper frame; the upper and lower ends of the conductor plate 15 are respectively connected with the ball screw 9 and the linear optical axis 16; the upper end of the damper frame 5 is installed with The linear bearing 6; the linear optical axis 16 passes through the linear bearing 6; the linear optical axis 16 is covered with a support spring 7 on the outer section of the linear bearing 6, and a spring baffle 8 is arranged at the other end of the support spring 7, and the spring baffle 8 and the linear light The shaft 16 is connected or limited on the linear optical axis 16; the support spring 7 is fixed between the linear bearing 6 and the spring baffle 8 to support the mass of the movable part of the damper.

In the test, the vibration of the model cable 17 drives the ball screw 9 to move in a straight line in the axial direction; due to the limitation of the thrust bearing 10, the movement of the ball screw 9 only causes the ball nut 11 to rotate in the frame body 1 of the damper frame . The ball nut 11 drives the mass flywheel to rotate and generate inertial mass, so that the damper has obvious negative stiffness characteristics.

Further, by changing the mass of the counterweight 14 or the lead of the ball screw 9, the inertial mass provided by the mass flywheel can be adjusted globally; and by changing the position of the counterweight 14 on the spokes 13, it can achieve The purpose of high-precision continuous adjustment of inertial mass in a local range.

The movement of the ball screw 9 drives the conductor plate 15 to move in the electromagnetic field generated by the electromagnet 3 . Due to the limitation of the linear bearing 6, the support spring 7 and the spring fastener 8, the conductor plate 15 only moves in-plane along the axial direction of the ball screw 9 in the magnetic field; There is no rotational movement along the conductor plate axis.

The movement of the conductor plate 15 in the magnetic field causes the phenomenon of electromagnetic induction, so that eddy currents are generated in the conductor plate 15 . Because of the existence of eddy currents, the conductor plate 15 moving in the magnetic field is affected by the Ampere force. According to Ampere’s theorem, the magnitude of the Ampere force is proportional to the speed of the conductor plate 15. Therefore, the Ampere force can be regarded as an equivalent viscosity The proportional coefficient of the hysteresis damping force is the equivalent viscous damping coefficient.

Further, changing the size of the electromagnet 3, the coil winding density of the electromagnet 3, and the material or size of the conductor plate 15 can greatly adjust the equivalent viscous damping coefficient globally; and changing the supply current of the electromagnet 3 can achieve The purpose of high-precision continuous adjustment of the damping coefficient in a local range.

Preferably, the conductor plate 15 is suggested to use a copper plate.

The weight of the ball screw 9, the spring baffle 8, the conductor plate 15 and the linear optical axis 16 are all supported by the support spring 7, which can reduce the influence of the weight of the above-mentioned movable parts on the model cable, so that the model cable does not have an initial Deformation, realize self-resetting function, can effectively improve the accuracy of test results.

Claims (6)

1. A parameter continuously adjustable self-resetting electric eddy current inertial mass damper for model stay cable vibration damping test is characterized in that, comprises damper frame, ball screw mechanism, quality flywheel, conductor plate, electromagnet and Linear Bearings; One end of the screw rod in the ball screw mechanism is connected with the model cable, and the other end is connected with the conductor plate; the ball nut in the ball screw mechanism and the conductor plate are arranged in the damper frame, and the The ball nut is positioned axially; The electromagnet is fixed on both sides of the damper frame, the conductor plate is located in the magnetic field generated by the electromagnet, and the reciprocating motion of the conductor plate can cut the magnetic field lines; the linear bearing is arranged on the upper side of the damper frame; The mass flywheel includes a drum, spokes and counterweights; the spokes are equally spaced on the drum; the counterweights are arranged on the spokes in a detachable or/and adjustable axial position ; The quality flywheel is set on the outside of the ball nut. 2. a kind of parameter continuously adjustable type self-resetting eddy current inertial mass damper for model cable-stayed vibration damping test according to claim 1, is characterized in that, described ball screw mechanism comprises screw rod, ball nut and Thrust bearings for axial positioning of roller nuts. 3. A kind of parameter continuously adjustable self-resetting electric eddy current inertial mass damper for model cable-stayed vibration damping test according to claim 1, it is characterized in that, described counterweight can be along described spoke axis sliding to change the moment of inertia of the mass flywheel, so as to achieve the purpose of adjusting the inertial mass; in the ball screw mechanism, only the screw moves axially and linearly with the vibration of the model stay cable and drives the conductor The plate moves linearly, and both the ball nut and the mass flywheel undergo rotational motion. 4. A kind of parameter continuously adjustable self-resetting eddy current inertial mass damper for model cable-stayed vibration damping test according to claim 1, it is characterized in that, described conductor plate upper end is equipped with linear optical axis, lower end Connected with the screw; the linear optical axis passes through the linear bearing; the part of the linear optical axis passing through the linear bearing is covered with a support spring; the end of the linear optical axis is equipped with a spring baffle; The support spring is limited on the linear optical axis by the spring baffle; the conductor plate only moves linearly in the plane under the restriction of the screw and the linear bearing; No out-of-plane rotational motion can occur under the restriction of the spring baffle. 5. A kind of parameter continuously adjustable self-resetting eddy current inertial mass damper for model cable-stayed vibration damping test according to claim 4, is characterized in that, its movable part comprises described screw rod, described conductor Plate, the optical axis and the spring baffle, the weight of the movable part is borne by the support spring; under the action of the support spring, the model cable will not be affected by the damper The weight of the moving part produces initial deformation, which reduces the experimental error of the model cable-stayed vibration test; under the action of the support spring, after each model cable-stayed vibration test, the model cable and the movable All parts will return to the initial balance position to realize the self-resetting function. 6. A kind of parameter continuous adjustable self-resetting eddy current inertial mass damper for model cable-stayed vibration damping test according to claim 1, it is characterized in that, the relative both sides of described damper frame are all set Electromagnet; the north and south poles of the electromagnet are arranged opposite to each other; the electromagnet generates an electromagnetic field through an external power supply; the strength of the electromagnetic field can be adjusted by adjusting the magnitude of the supply current; the conductor moves in the electromagnetic field to generate an equivalent viscous damping force, changing the electromagnetic field Iron supply current can adjust the damping coefficient.

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