CN111810582A

CN111810582A - Electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber

Info

Publication number: CN111810582A
Application number: CN202010706076.1A
Authority: CN
Inventors: 李鹏涛; 张彦峰; 代海; 玉昊昕; 宁晓峰; 刘玲
Original assignee: Xi'an Acoustic Technology Co ltd
Current assignee: Xi'an Acoustic Technology Co ltd
Priority date: 2020-07-21
Filing date: 2020-07-21
Publication date: 2020-10-23
Anticipated expiration: 2040-07-21
Also published as: CN111810582B

Abstract

The invention belongs to the field of vibration absorption, in particular to an electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber which comprises a magnetic conduction shell and is characterized in that two cavity clapboards are symmetrically and fixedly arranged in the magnetic conduction shell, the two cavity clapboards are arranged along the vertical direction, two first square cavities are symmetrically arranged between one end, away from each other, of the two cavity clapboards and the inner wall of the magnetic conduction shell, the two first square cavities are arranged along the vertical direction, a magnetic conduction pressing block is positioned at the middle position of the inner sides of the cavity clapboards and the inner wall of the magnetic conduction shell, one end, close to each other, of the two cavity clapboards is provided with a second square cavity, the second square cavity is positioned at the middle position between the two cavity clapboards, and the second square cavity is arranged along the front-back direction, the invention has the advantages of good vibration absorption effect, higher control precision and good control effect.

Description

Electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber

Technical Field

The invention relates to the technical field of vibration absorption, in particular to an electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber.

Background

The magnitude of mechanical vibration is an important factor influencing the performance of mechanical equipment, how to efficiently reduce the vibration of the mechanical equipment is always one of the hot problems of research in the mechanical field, and generally, the control measures for the vibration mainly comprise the technologies of vibration absorption, vibration isolation, vibration absorption, vibration resistance and the like. The dynamic vibration absorption technology is characterized in that a dynamic vibration absorber is added on a controlled object, the rigidity of an elastic element of the dynamic vibration absorber or the mass of an inertia element is adjusted on line by identifying the difference between an external excitation frequency and the natural frequency of the dynamic vibration absorber, so that the natural frequency of the dynamic vibration absorber is always consistent with the external excitation frequency, the movement direction is opposite, and the movement frequency is in a tunable state at any moment.

The conventional dynamic vibration absorbers can be roughly classified into: passive, semi-active, active. The passive vibration absorber has a relatively simple structure, is convenient to install and has stable performance, but because the structural parameters of the passive vibration absorber are relatively fixed, the passive vibration absorber can only realize the vibration reduction task in a narrow-band range near the natural frequency of the passive vibration absorber, and has poor effect of inhibiting the excitation vibration in a wide-band range; in order to solve the problem of poor vibration absorption function in a wide frequency range, semi-active and active vibration absorbers with tunable frequency are provided. The vibration absorber achieves the purpose of absorbing vibration by changing the dynamic parameters of the vibration absorber such as rigidity, damping, mass and the like to enable the natural frequency of the vibration absorber to track the change of external excitation frequency.

The conventional CN108155773B is a tunable two-degree-of-freedom electromagnetic vibration absorber, which comprises a shell, a resonance device, a natural frequency adjusting device, an energy consumption device and the like. Wherein the resonance device comprises a permanent magnet, a magnet and a flexible connecting rod for connecting the permanent magnet and the magnet; the natural frequency adjusting device comprises a stepping motor, a bidirectional ball sliding screw, a movable supporting beam and the like.

In the resonance device, the permanent magnet is arranged inside the shell through the flexible connecting piece, one end of the flexible connecting piece is connected with the left side of the shell, the other end of the flexible connecting piece penetrates through the right side of the shell to be connected with the tensioning device, the two magnets are arranged on the left side and the right side of the permanent magnet respectively and are arranged on the left surface and the right surface inside the shell, the magnetic pole of the magnet on the left side is the same as the magnetic pole on the left side of the permanent magnet, and the magnetic.

In CN108155773B, the natural frequency adjusting device receives a real-time signal from an acceleration sensor in the unit, and after calculation processing by an internal DSP, the stepping motor rotates to drive the sliding lead screw to adjust the length of the flexible connecting rod participating in vibration, so as to achieve the purpose of changing the natural frequency. Specifically, the acceleration sensor of the whole vibration damping system measures the frequency and the magnitude of the exciting force of an external environment in real time, the DSP chip performs FFT (fast Fourier transform) in real time according to a measured vibration signal to obtain a main frequency f of vibration damping, and adjusts the rotating speed of the stepping motor in real time according to the f, so that the length of the flexible rod connecting piece participating in vibration is changed, the natural frequency of the vibration damper is changed in real time, and the purpose of damping a controlled object is achieved.

In summary, the main problems of the prior art are: (1) the natural frequency adjusting device of the system belongs to a mechanical adjusting device, a plurality of mechanical components are provided, and an actuating mechanism is relatively complex, so that the uncontrollable performance and the nonlinear degree of a transfer function of the whole system are greatly increased, and the control difficulty and the control precision of the system are increased; (2) due to the influence of various factors such as deformation, part processing precision, rotation precision control of a stepping motor and the like in the movement process of the bidirectional ball sliding screw, the control precision of the whole self-tuning two-degree-of-freedom electromagnetic vibration absorber system is also influenced, and the control precision is unfavorable for the precise control of micro vibration. Further provides an electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber.

Disclosure of Invention

The invention provides an electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber, which solves the problems of poor vibration absorbing effect and complex and troublesome operation of the conventional vibration absorber.

In order to achieve the purpose, the invention adopts the following technical scheme:

an electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber comprises a magnetic conduction shell and is characterized in that two cavity partition plates are symmetrically and fixedly installed inside the magnetic conduction shell, the two cavity partition plates are arranged in the vertical direction, two first square cavities are symmetrically installed between one end, away from each other, of each cavity partition plate and the inner wall of the magnetic conduction shell, the two first square cavities are arranged in the vertical direction, a magnetic conduction pressing block is located in the middle position of the inner sides of the cavity partition plates and the inner wall of the magnetic conduction shell, a second square cavity is installed at one end, close to each other, of each cavity partition plate, the second square cavity is located in the middle position between the two cavity partition plates, the second square cavity is arranged in the front-back direction, magnetic conduction pressing irons are installed inside the two first square cavities and the second square cavities in the vertical direction and the front, and the magnetic conduction iron weight is fixedly provided with a permanent magnet, and the two first square chamber inner walls and the second square chamber inner walls are respectively provided with three coils at equal intervals in the vertical direction and the front-back direction.

Preferably, two the inside wall of the first square chamber and the second square chamber is respectively provided with a smooth guide rail along the vertical direction and the front-back direction through fixing bolts in a detachable fixed manner, the rear end of the magnetic conduction iron weight is fixedly provided with a smooth guide block, and the smooth guide block is slidably arranged on the smooth guide rail.

Preferably, the upper end and the lower end of each magnetic conductive weight in the first square chamber are fixedly connected with the inner wall of the first square chamber through springs, and the front end and the rear end of each magnetic conductive weight in the second square chamber are fixedly connected with the inner wall of the second square chamber through springs.

Preferably, the magnetic conduction shell is internally and symmetrically arranged at the front side and the rear side of the first square cavity and is provided with bottom fixing bolts.

Preferably, the inner walls of the first square chamber and the second square chamber are fixedly connected with the coil through coil holders.

Preferably, the magnetic conduction shell and the chamber partition plate are made of low-carbon steel.

The invention has the beneficial effects that: the invention can realize real-time accurate control on the magnitude, direction and frequency of the output force by receiving the control signal of the peripheral digital circuit of the system; the invention has wide frequency band range, higher control precision and good control effect, is particularly suitable for the vibration suppression of the traditional passive vibration absorber which cannot be controlled and is caused by variable excitation and has wider frequency band, solves the defects that the effective vibration absorption frequency band of the traditional passive dynamic vibration absorber is narrower and the vibration reduction requirement under the working condition of real-time variable external excitation force cannot be met, and can adjust the self frequency and phase in real time according to the change of the external excitation force to realize the suppression of variable frequency excitation vibration; compared with the traditional vibration absorber, the vibration absorber is mostly unidirectional no matter a fixed frequency or tunable vibration absorber; the electromagnetic coupling tunable dynamic vibration absorber designed in the invention has two degrees of freedom, and can simultaneously inhibit the vibration in the directions of the two degrees of freedom, thereby greatly reducing the cost of vibration inhibition; the internal structure of the invention is composed of independent chambers which are mutually shielded, the structural design has less magnetic leakage effect, and the utilization rate of magnetic flux is improved; the peripheral auxiliary digital control system comprises a DSP part, an AD part, a DA part and the like, can be integrated and modularized, is convenient for the accurate control of the whole system, and has high efficiency-cost ratio.

Drawings

Fig. 1 is a schematic structural diagram of an electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber according to the present invention.

Fig. 2 is a left side view of an electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber according to the present invention.

Fig. 3 is a top view of an electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber according to the present invention.

Fig. 4 shows a left side view of an electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber according to the present invention.

Reference numbers in the figures: 1 magnetic conduction weight, 2 permanent magnets, 3 magnetic conduction shells, 4 coils, 5 coil retainers, 6 springs, 7 smooth guide blocks, 8 chamber partition plates, 9 fixing bolts, 10 smooth guide rails, 11 bottom fixing bolts, 12 first square chambers and 13 second square chambers.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.

Referring to fig. 1-4, an electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber comprises a magnetic conduction shell 3, two cavity partition plates 8 are symmetrically and fixedly installed inside the magnetic conduction shell 3, the two cavity partition plates 8 are arranged in the vertical direction, two first square cavities 12 are symmetrically installed between one ends, away from each other, of the two cavity partition plates 8 and the inner wall of the magnetic conduction shell 3, the two first square cavities 12 are arranged in the vertical direction, a magnetic conduction pressing block is located at the middle position of the inner sides of the cavity partition plates 8 and the inner wall of the magnetic conduction shell 3, a second square cavity 13 is installed at one end, close to each other, of the two cavity partition plates 8, the second square cavity 13 is located at the middle position between the two cavity partition plates 8, the second square cavity 13 is arranged in the front-back direction, magnetic conduction pressing irons 1 are installed inside the two first square cavities 12 and the second square cavity 13 in the, and permanent magnets are fixedly mounted on the magnetic conduction iron weight 1, and two coils 4 are respectively mounted on the inner wall of the first square cavity 12 and the inner wall of the second square cavity 13 at equal intervals in the vertical direction and the front-back direction.

In this embodiment, the inner walls of the two first square chambers 12 and the second square chambers 13 are respectively and fixedly provided with a smooth guide rail 10 along the vertical direction and the front-back direction through fixing bolts 9 in a detachable manner, the rear end of the magnetic conductive press 1 is fixedly provided with a smooth guide block 7, the smooth guide block 7 is slidably mounted on the smooth guide rail 10, the upper and lower ends of the magnetic conductive press 1 in the two first square chambers 12 are fixedly connected with the inner wall of the first square chamber 12 through springs 6, the front and back ends of the magnetic conductive press 1 in the second square chamber 13 are fixedly connected with the inner wall of the second square chamber 13 through springs 6, bottom fixing bolts 11 are respectively mounted inside the magnetic conductive casing 3 and symmetrically arranged on the front and back sides of the first square chamber 12, the inner walls of the first square chamber 12 and the second square chamber 13 are fixedly connected with the coil 4 through a coil retainer 5, the magnetic conduction shell 3 and the chamber partition plate 8 are made of low-carbon steel.

Example (b): as shown in fig. 1 and 3, the magnetic conductive housing 3 of the tunable dynamic vibration absorber is a rectangular parallelepiped structure, the internal structure of the tunable dynamic vibration absorber can be divided into three rows, i.e., a left row, a middle row and a right row, the two rows of structures on two sides can be divided into three chambers, i.e., an upper chamber, a middle chamber and a lower chamber, along the front-to-back direction, and the middle row can be divided into three layers, i.e., an upper layer, a middle layer and a lower layer, along the upper-to-back direction, so that the total number of the whole structure is nine chambers, which are separated by chamber partitions 8, to form independent magnetic cavity closed structures, the middle position of each row of structures is designed into a large square-section chamber, i.e., a first square chamber 12 and a second square chamber 13, a smooth guide rail 10 is arranged at the center positions of the first square chamber 12 and the second square chamber 13 along the upper-to-down direction of, The mass of the middle inertia mass unit is 2 times of that of the two side inertia mass units. As shown in fig. 2 to 4, the coil 4 provided on the inner walls of the first square chamber 12 and the second square chamber 13 is concentric with the smooth rail 10 of the slidable inertial mass unit, and the coil 4 is fixed on the upper surface of the coil holder 5, and then the magnetic field and the movable mass unit are formed in the first square chamber 12 and the second square chamber 13 in three directions perpendicular to each other. Because the chamber partition plate 8 is made of low-carbon steel which is a magnetic conductive material, magnetic fields generated inside the first square chamber 12 and the second square chamber 13 are absorbed by the chamber partition plate 8 and rarely leak, and independent magnetic field loops are formed in the first square chamber 12 and the second square chamber 13, so that the mutual influence of the magnetic fields between the first square chamber 12 and the second square chamber 13 is small. As shown in fig. 2 to 4, the coils 4 in the first square chamber 12 and the second square chamber 13 are respectively located in the independent magnetic field loops generated by the permanent magnet 2, so that the sub-chamber design has the advantage of solving the problems of magnetic leakage and mutual magnetic field interference between different chambers. According to the faraday's law of electromagnetic induction, f, bil, the coil 4 is subject to an ampere force in the magnetic field, the magnitude of the ampere force is related to the magnitude of the current, the strength of the magnetic field, the effective length of the coil 4, etc., and the direction thereof can be determined according to the left-hand rule. By adjusting and varying the magnitude and direction of the current in the coil 4, the coil 4 is subjected to a varying, controllable force in the magnetic field. As shown in fig. 1, according to the faraday's law of electromagnetic induction, each set of coils 4 in the two first square chambers 12 is in the permanent magnetic field loop formed by the inertial mass unit, when the coil 4 passes through the current with the changing magnitude and direction, the coil 4 will be acted by the alternating ampere force, but because the coil 4 is always in the fixed state and can not move, according to the newton's law of first, the inertial mass unit part of the permanent magnet 2 and the magnetic conductive iron weight 11, etc. in the magnetic field will be acted by the reaction force of the ampere force to generate the reciprocating motion along the smooth guide rail 10. By providing the springs 6 at both end positions of the smooth guide rail 10, i.e., at both ends of the inertial mass unit, the force generated by the reciprocating motion of the inertial mass unit can be damped, thus forming a vibration effect in the up-down direction. In fig. 3, the same principle is applied, in which the coil 4 in the second square chamber 13 is in the magnetic field generated by the intermediate inertial mass unit, and the coil 4 is energized, the coil 4 is acted by a ampere-multiple force, and with the coil 4 fixed, the inertial mass unit generates a reaction force to move along the intermediate smooth rail 10, and by changing the magnitude and direction of the current of the coil 4, the acceleration and direction of the movement of the inertial mass unit can be changed, thus generating a vibration effect in the front-back direction. Because the smooth guide rails 10 in the front and back direction and the up and down direction are perpendicular to each other, the invention can output the force action in the two directions to the outside, which is the technical principle of the invention. In order to control the magnitude, direction and frequency of the output force, the current input into the vibration absorber is adjusted by a digital circuit control system. It should be noted here that in fig. 1, the smooth guide rails 10 of a single inertial mass unit in the two first square chambers 12 are symmetrically arranged on both sides of the middle inertial mass, and the mass of the middle inertial mass unit is 2 times that of the two side inertial mass units, and the two side inertial mass units adopt a synchronous and equidirectional movement mode. The advantages of this design are: when the invention is in a working state, the motion of the two inertial mass units at the two sides always keeps the synchronization and the direction in the size and the direction, and the motion is on the same plane, the eccentric moments generated by the two inertial mass units at the two sides relative to the mass center of the invention are equal in size and opposite in direction, so that the two inertial mass units are mutually offset, and for the invention, only the action of external output force is realized, and no eccentric moment exists. Because the mass of the middle inertia mass unit is 2 times of that of the two side inertia mass units, the linear relation is convenient for real-time control of the output force and the direction of the invention under the working state. In fig. 3 and 4, four bolts 9 are arranged at the vacant positions of the four corners of the internal cavity of the whole structure for mounting and fixing the invention on the controlled object. The invention can realize real-time accurate control on the magnitude, direction and frequency of the output force by receiving the control signal of the peripheral digital circuit of the system; the vibration suppression device has the advantages of wide frequency band range, high control precision and good control effect, and is particularly suitable for the vibration suppression of the traditional passive vibration absorber which cannot be controlled, is caused by variable excitation and has a wider frequency band; compared with the traditional vibration absorber, the vibration absorber is mostly unidirectional no matter a fixed frequency or tunable vibration absorber; the electromagnetic coupling tunable dynamic vibration absorber designed in the invention has two degrees of freedom, and can simultaneously inhibit the vibration in the directions of the two degrees of freedom, thereby greatly reducing the cost of vibration inhibition; the internal structure of the invention is composed of independent chambers which are mutually shielded, the structural design has less magnetic leakage effect, and the utilization rate of magnetic flux is improved; the peripheral auxiliary digital control system comprises a DSP part, an AD part, a DA part and the like, can be integrated and modularized, is convenient for the accurate control of the whole system, and has high efficiency-cost ratio.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the equipment or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.

Claims

1. The electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber comprises a magnetic conduction shell (3) and is characterized in that two cavity partition plates (8) are symmetrically and fixedly mounted inside the magnetic conduction shell (3), the two cavity partition plates (8) are arranged in the vertical direction, two first square cavities (12) are symmetrically mounted between one ends, away from each other, of the two cavity partition plates (8) and the inner wall of the magnetic conduction shell (3), the two first square cavities (12) are arranged in the vertical direction, a magnetic conduction pressing block is located in the middle positions of the inner sides of the cavity partition plates (8) and the inner wall of the magnetic conduction shell (3), one ends, close to each other, of the two cavity partition plates (8) are provided with second square cavities (13), the second square cavities (13) are located in the middle positions between the two cavity partition plates (8), and the second square cavities (13) are arranged in the front-back direction, two magnetic conduction weights (1) are installed along vertical direction and fore-and-aft direction respectively to first square cavity (12) and second square cavity (13) inside, fixed mounting has the permanent magnet on magnetic conduction weights (1), two equal equidistance in vertical direction and the fore-and-aft direction is installed respectively to first square cavity (12) inner wall and second square cavity (13) inner wall three coil (4).

2. The electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber according to claim 1, wherein the inner walls of the first square chamber (12) and the second square chamber (13) are detachably and fixedly provided with smooth guide rails (10) by fixing bolts (9) along the vertical direction and the front-back direction, respectively, the rear end of the magnetic conductive weight (1) is fixedly provided with a smooth guide block (7), and the smooth guide block (7) is slidably arranged on the smooth guide rails (10).

3. The electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber according to claim 1, wherein the upper and lower ends of the magnetic conductive weights (1) in the first square chamber (12) are fixedly connected with the inner wall of the first square chamber (12) through springs (6), and the front and rear ends of the magnetic conductive weights (1) in the second square chamber (13) are fixedly connected with the inner wall of the second square chamber (13) through springs (6).

4. The electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber according to claim 1, wherein bottom fixing bolts (11) are installed inside the magnetic conductive housing (3) and symmetrically arranged on the front side and the rear side of the first square chamber (12).

5. The electromagnetic coupling tunable two-degree-of-freedom dynamic vibration absorber of claim 1, wherein the inner walls of the first square chamber (12) and the second square chamber (13) are fixedly connected with the coil (4) through a coil holder (5).