CN116044943A

CN116044943A - Series-parallel nonlinear absorber cell

Info

Publication number: CN116044943A
Application number: CN202310014516.0A
Authority: CN
Inventors: 丁虎; 曾佑成; 邓天昌; 毛晓晔; 陈立群
Original assignee: University of Shanghai for Science and Technology
Current assignee: University of Shanghai for Science and Technology
Priority date: 2023-01-05
Filing date: 2023-01-05
Publication date: 2023-05-02

Abstract

The invention discloses a series-parallel nonlinear absorber cell which consists of a mass block, a steel wire rope, a linear bearing, a linear guide rod, a guide rod bracket, a magnet fixing block, a ring magnet, a steel wire rope fixing frame, a linear guide rod fixing frame, a linear slider, a linear guide rail and an outer frame. The invention realizes the serial connection and parallel connection of the nonlinear absorber cells by using different connection modes. The magnetic force between the ring magnets can limit the large vibration of the nonlinear absorber cell, and the reliability of the nonlinear absorber cell is improved. The universality of the nonlinear absorber for suppressing the vibration of different main systems is improved by adjusting the number of cells of the nonlinear absorber connected in series and in parallel. The device has simple structure, easy realization and wide application range.

Description

Series-parallel nonlinear absorber cell

Technical Field

The invention relates to the technical field of passive vibration control, in particular to a series-parallel nonlinear absorber cell.

Background

Vibration is common in engineering practice. Vibration is detrimental in many areas. For example, vibrations may cause an abnormal operation of the work machine, thereby causing a malfunction; wind-induced vibration effects can lead to collapse of high-rise buildings and bridges; vibration of the aircraft wing caused by airflow can affect the stability of the flight; the slight vibration is a main cause of deterioration of the imaging quality of the satellite. Therefore, effective suppression of harmful vibrations of the structure is required.

Shock absorption is a method of effectively suppressing vibration. The conventional linear absorber acts only on a single frequency, and the vibration suppression band is narrow. To overcome the above difficulties, a nonlinear vibration reduction concept has been proposed. When the nonlinear restoring force of the nonlinear absorber is larger than the linear restoring force, the nonlinear absorber has the characteristic of broadband vibration reduction, and can adaptively control resonance in a broadband. However, the weight of the vibration absorber often needs to be in a certain proportion to the weight of the vibration main structure to have good vibration damping efficiency, and thus, for vibration control of a large-scale engineering structure, the weight of the vibration absorber may be large. The nonlinear vibration absorber tends to vibrate more than the main structure itself when the vibration is damped at high efficiency, and the single nonlinear vibration absorber is very low in reliability as soon as the vibration absorber device is destroyed when it works. The weight requirements of the nonlinear vibration absorber are different for different main systems, and once the main system is changed greatly, the nonlinear vibration absorber may need to be redesigned, so that the universality of the single nonlinear vibration absorber is low. The large additional weight, low reliability and versatility make the nonlinear vibration absorber very limited in solving practical engineering problems.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a series-parallel nonlinear absorber cell, wherein the maximum amplitude of the nonlinear absorber is limited by acting force between magnets, and the reliability and the universality of the vibration control of the nonlinear absorber are improved by connecting a large number of light nonlinear absorbers with broadband control in series or in parallel.

In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:

a series-parallel nonlinear vibration absorber cell consists of a mass block, a steel wire rope, a linear bearing, a linear guide rod, a guide rod bracket, a magnet fixing block, a ring magnet, a steel wire rope fixing frame, a linear guide rod fixing frame, a linear sliding block, a linear guide rail and an outer frame. The mass block is sleeved on the linear guide rod through the linear bearing, and the mass block can only move along the linear guide rod. The mass block is internally provided with a through groove, the steel wire rope penetrates through the through groove, and two ends of the steel wire rope are fixed on the steel wire rope fixing frame through the fixing block and the bolt. The bolt passes through a threaded hole above the mass block to fixedly connect the midpoint of the steel wire rope with the mass block; the mass moves along the linear guide rod, and the wire rope generates nonlinear restoring force in the moving direction of the mass. The two ends of the linear guide rod are fixed in the guide rod bracket, and the guide rod bracket is connected with the linear guide rod fixing frame through bolts. The ring magnet is fixed on one side of the magnet fixing block, the magnet fixing block is fixed on the linear guide rod by the bolts, the ring magnet is fixed on the linear bearing, and the distance between the ring magnets can be changed by moving the magnet fixing block along with the movement of the mass blocks, so that acting force between the magnets is changed. Threaded holes are formed in the middle of the steel wire rope fixing frame and the middle of the linear guide rod fixing frame, and the steel wire rope fixing frame and the linear guide rod fixing frame are connected through bolts. The wire rope fixed frame is connected with the linear sliding block through the bolt, the linear sliding block can move in the linear track, and the linear sliding block can be fixed on the linear guide rail through the bolt. The linear track is fixedly connected with the outer frame through bolts.

The polarity of the ring magnets on the same side of the mass is opposite.

The position of the magnet fixing block can be moved to change acting force between the ring magnets, so that the movement range of the nonlinear absorber mass block is limited.

The series-parallel nonlinear absorber cells can be connected through bolts, so that the number of the cells is increased or reduced.

The bolts are screwed down to fix the linear sliding blocks and the linear guide rails, and the outer frames of the single nonlinear absorber cells are connected through the bolts, so that the parallel nonlinear absorber cells are formed.

The bolts are unscrewed to enable the linear sliding blocks to move on the linear guide rails, the outer frames of the single nonlinear absorber cells are connected through the bolts, and the steel wire rope fixing frame and the linear guide rod fixing frame are connected with the next layer of mass blocks and the steel wire ropes through the serial bolts, so that the serial nonlinear absorber cells are formed.

Compared with the prior art, the invention has the beneficial effects that:

1. the maximum amplitude of the nonlinear vibration absorber can be limited by the ring magnet, so that the reliability of the device is improved.

2. The light weight and the cell are realized by connecting a large number of light nonlinear vibration absorber cells in series and parallel, so that the reliability and the universality in the application are improved.

Drawings

FIG. 1 is a schematic diagram of a nonlinear absorber cell structure.

FIG. 2 is a schematic diagram of a parallel nonlinear absorber cell structure.

FIG. 3 is a schematic diagram of a cell structure of a series nonlinear absorber.

FIG. 4 is a schematic diagram of vibration suppression for a single degree of freedom system in accordance with an embodiment of the present invention.

Fig. 5 is a graph of the number of parallel nonlinear energy cells versus damping efficiency.

Wherein: 1. the mass block, 2, a second bolt, 3, a steel wire rope, 4, a clamping block, 5, a first bolt, 6, a linear bearing, 7, a linear guide rod, 8, a guide rod bracket, 9, a third bolt, 10, a magnet fixing block, 11, a fourth bolt, 12, a first ring magnet, 13, a second ring magnet, 14, a steel wire rope fixing frame, 15, a linear guide rod fixing frame, 16, a fifth bolt, 17, a sixth bolt, 18, a linear slider, 19, a linear guide rail, 20, a seventh bolt, 21, an eighth bolt, 22, an outer frame, 23, a ninth bolt, 24 and a serial bolt. 25. Single degree of freedom vibrator.

Detailed Description

The present invention now will be described more fully hereinafter with reference to the accompanying drawings.

As shown in fig. 1, in a series-parallel nonlinear absorber cell, a mass block 1 is sleeved on a linear guide rod 7 through a linear bearing 6, and the mass block 1 can only move along the linear guide rod 7; a through groove is formed in the mass block 1, a steel wire rope 3 passes through the through groove, and two ends of the steel wire rope are fixed on a steel wire rope fixing frame 14 through a fixing block 4 and a first bolt 5; the second bolt 2 passes through a threaded hole above the mass block 1 to fixedly connect the midpoint of the steel wire rope 3 with the mass block 1; when the mass block 1 moves along the linear guide rod 7, the steel wire rope 3 generates pure nonlinear restoring force in the movement direction of the mass block 1; two ends of the linear guide rod 7 are fixed in the guide rod bracket 8, and the guide rod bracket 8 is connected with the linear guide rod fixing frame 15 through a third bolt 9; the first ring magnet 12 is fixed on one side of the magnet fixing block 10, the fourth bolt 11 is used for fixing the magnet fixing block 10 on the linear guide rod 7, the second ring magnet 13 is fixed on the linear bearing 6, and screw holes are formed in the middle of the steel wire rope fixing frame 14 and the middle of the linear guide rod fixing frame 15 along with the movement of the mass block 1, and the steel wire rope fixing frame and the linear guide rod fixing frame are connected through the fifth bolt 16; the wire rope fixing frame 14 is connected to the linear slider 18 by a sixth bolt 17, the linear slider 18 is movable on the linear rail 19, or the linear slider 18 is fixed to the linear rail 19 by an eighth bolt 21, and a seventh bolt 20 fixes the linear rail 19 to the outer frame 22.

The polarity of the ring magnets on the same side of the mass 1 is opposite.

The position of the magnet fixing block 10 is moved to change the distance between the two ring magnets, so as to change the acting force between the magnets, thereby controlling the movement range of the mass block 1.

The series-parallel nonlinear absorber cells are connected through a ninth bolt 23, so that the number of the nonlinear absorber cells is increased or reduced.

As shown in fig. 2, the eighth bolt 21 is tightened so that the linear slider 18 is fixed to the linear guide 19, the outer frame 22 of the individual nonlinear absorber cells is connected by the ninth bolt 23, and only the wire rope fixing frame 14 and the linear guide fixing frame 15 are connected by the fifth bolt 16, and the mass blocks 1 of the individual nonlinear absorber cells are independently moved, thereby constituting the parallel absorber cells.

As shown in fig. 3, the eighth bolt 21 is loosened, so that the linear slider 18 moves on the linear guide rail 19, the outer frame 22 of the single nonlinear absorber cell is connected through the ninth bolt 23, the wire rope fixing frame 14 and the linear guide rod fixing frame 15 are connected with the mass block 1 and the wire rope 3 of the cell of the next layer through the serial bolts 24, and the mass block 1 of the cell of the previous layer and the mass block 1 of the cell of the next layer are relatively displaced, so that the serial nonlinear absorber cell is formed.

As shown in fig. 4, taking a single degree of freedom as an example, the parallel nonlinear absorber cell of the invention is fixed at the upper end of the single degree of freedom vibrator 25, and the bottom is subjected to displacement excitation to drive the parallel nonlinear absorber cell to vibrate together.

As shown in fig. 5, from the relationship between the number of cells of the parallel nonlinear absorber and the vibration reduction efficiency, the vibration reduction efficiency of the nonlinear absorber gradually increases to be stable as the number of cells gradually increases. It can be seen that for different quality main systems, excellent damping performance can be obtained by only increasing or decreasing the number of nonlinear absorber cells, without redesigning a new nonlinear absorber to match with a different main system. In addition, when a single nonlinear absorber is operated, once the absorber device is damaged, the vibration control of the structure is disabled, while for the present invention, one nonlinear absorber cell is damaged, and the vibration absorbing efficiency is not greatly affected. Therefore, the series-parallel nonlinear absorber cell provided by the invention can greatly improve the reliability and the universality of the nonlinear absorber in engineering practice.

The invention relates to a series-parallel nonlinear absorber cell, which comprises the following specific use methods: when an external stimulus acts on the main system, the main system produces vibrations. After the serial and parallel nonlinear absorber cells are added to the main system, vibration energy of the main system is transmitted to the serial and parallel nonlinear absorber cells in one direction, so that the mass blocks of the nonlinear absorber cells generate large vibration to dissipate the energy of the main system, and the mass blocks of the nonlinear absorber cells are limited in a certain movement range due to the existence of the ring magnets. The number of parallel or series nonlinear absorber cells can be conveniently increased or decreased according to the weights of different main systems and single nonlinear absorber cells to obtain the best vibration reduction efficiency. When the controlled object changes, the number of the nonlinear absorber cells is only increased or decreased appropriately, and the nonlinear absorber is not required to be redesigned. In addition, when the structure of a single nonlinear absorber cell is damaged, other nonlinear absorber cells connected in series and parallel can still work normally.

The embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to the embodiments described above, and various changes, modifications, substitutions, combinations or simplifications made under the spirit and principles of the technical solution of the present invention can be made according to the purpose of the present invention, and all the changes, modifications, substitutions, combinations or simplifications should be equivalent to the substitution, so long as the purpose of the present invention is met, and all the changes are within the scope of the present invention without departing from the technical principles and the inventive concept of the present invention.

Claims

1. The series-parallel nonlinear absorber cell is characterized in that a mass block (1) is sleeved on a linear guide rod (7) through a linear bearing (6), and the mass block (1) can only move along the linear guide rod (7); the mass block (1) is internally provided with a through groove, the steel wire rope (3) passes through the through groove, and two ends of the steel wire rope are fixed on the steel wire rope fixing frame (14) through the fixing block (4) and the first bolt (5); the second bolt (2) passes through a threaded hole above the mass block (1) to fixedly connect the midpoint of the steel wire rope (3) with the mass block (1); when the mass block (1) moves along the linear guide rod (7), the steel wire rope (3) generates pure nonlinear restoring force in the movement direction of the mass block (1); two ends of a linear guide rod (7) are fixed in a guide rod bracket (8), and the guide rod bracket (8) is connected with a linear guide rod fixing frame (15) through a third bolt (9); the first ring magnet (12) is fixed on one side of the magnet fixing block (10), the fourth bolt (11) is used for fixing the magnet fixing block (10) on the linear guide rod (7), the second ring magnet (13) is fixed on the linear bearing (6), threaded holes are formed in the middle of the steel wire rope fixing frame (14) and the middle of the linear guide rod fixing frame (15) along with the movement of the mass block (1), and the steel wire rope fixing frame and the linear guide rod fixing frame are connected through the fifth bolt (16); the wire rope fixed frame (14) is connected with the linear sliding block (18) through a sixth bolt (17), the linear sliding block (18) can move on the linear rail (19), or the linear sliding block (18) is fixed on the linear rail (19) through an eighth bolt (21), and the linear rail (19) and the outer frame (22) are fixed through a seventh bolt (20).

2. The series-parallel nonlinear absorber cell according to claim 1, wherein the polarities of the ring magnets on the same side of the mass (1) are opposite.

3. The series-parallel nonlinear absorber cell according to claim 1, wherein the position of the magnet fixing block (10) is moved to change the distance between two ring magnets, thereby changing the acting force between the magnets, and thus controlling the movement range of the mass block (1).

4. The series-parallel nonlinear absorber cell according to claim 1, wherein the series-parallel nonlinear absorber cells are connected by a ninth bolt (23) to increase or decrease the number of nonlinear absorber cells.

5. The series-parallel nonlinear absorber cell according to claim 1, wherein the eighth bolt (21) is tightened to fix the linear slider (18) to the linear guide rail (19), the outer frame (22) of the single nonlinear absorber cell is connected by the ninth bolt (23), and only the wire rope fixing frame (14) and the linear guide rod fixing frame (15) are connected by the fifth bolt (16), thereby forming the parallel absorber cell.

6. The series-parallel nonlinear absorber cell according to claim 1, wherein the eighth bolt (21) is unscrewed to enable the linear slider (18) to move on the linear guide rail (19), the outer frame (22) of the single nonlinear absorber cell is connected through the ninth bolt (23), and the wire rope fixing frame (14) and the linear guide rod fixing frame (15) are connected with the mass block (1) and the wire rope (3) of the next layer of cells through the series bolts (24), so that the series nonlinear absorber cell is formed.