CN216519352U - Negative stiffness dynamic vibration absorber based on permanent magnet - Google Patents

Abstract

The utility model relates to a negative stiffness dynamic vibration absorber based on permanent magnets, which comprises a base, a dynamic vibration absorber, a liftable clamping device and four permanent magnets. The utility model can meet the various requirements of the laboratory for the negative stiffness vibration absorber, improve the utilization rate, reduce the cost, can change the negative stiffness item of the system by changing the relative displacement of the permanent magnet, and can also install and remove the I-shaped groove slide. The channel and the I-shaped groove slider enable the negative stiffness dynamic vibration absorber to perform the vibration reduction experiment of the negative stiffness dynamic vibration absorber in the two working environments of the vibration platform or the vibration exciter, and meet the requirements of vibration and optical precision experiments.

Description

A Negative Stiffness Dynamic Vibration Absorber Based on Permanent Magnets

technical field

The utility model relates to the fields of mechanical design, vibration machinery and the like, in particular to an experimental device for a negative stiffness dynamic vibration absorber which can be used in two working environments of a vibration platform and a vibration exciter.

Background technique

Vibration systems containing negative stiffness springs have the advantages of low natural frequency, large bearing capacity, and good vibration damping effect. Therefore, in recent years, negative stiffness components have been used more and more in vibration damping. However, since the realization of negative stiffness springs is difficult, there is no mature experimental equipment design method for the negative stiffness dynamic vibration absorber model, and users need to respond according to the type of experiments they do. Therefore, it is more and more necessary to design a set of simple experimental equipment that can perform vibration reduction experiments of negative stiffness dynamic vibration absorbers in various working environments.

Utility model content

The purpose of the utility model is to solve the technical problems existing in the prior art, and to provide a negative stiffness dynamic vibration absorber based on permanent magnets, which can meet the various demands of laboratories for the negative stiffness vibration absorber, improve the utilization rate, and reduce the cost. The negative stiffness can be controlled by changing the relative displacement of the permanent magnet. By installing and removing the I-shaped groove slideway and the I-shaped groove sliding block, the negative stiffness dynamic vibration absorber can be operated in two working environments: a vibration platform or a vibration exciter. Carry out experiments to meet the requirements of precision experiments of vibration and optics.

The utility model is realized through the following technical solutions.

A negative stiffness dynamic vibration absorber based on permanent magnets, comprising a base, a dynamic vibration absorption device, a liftable clamping device, and four permanent magnets;

The base is provided with a through hole, and the through hole is used to fix the base on the vibration platform, and the vibration platform excites the base to vibrate;

The dynamic vibration absorption device includes a mass block 1 and a mass block 2, the mass block 1 and the mass block 2 are connected by a manganese steel sheet 1 and a screw, and the mass block 1 and the base are connected by a manganese steel sheet 2 and screw connection, the second mass block is located between the first mass block and the base;

The liftable clamping device includes a hand-operated single-track ball screw slide table, a cylindrical linear guide rail, two fixing blocks 1 and 2, and the cylindrical linear guide rails are arranged in parallel on the hand-operated single-track ball screw. On one side of the rod sliding table, the cylindrical linear guide rail is provided with a sliding block with a lock, two fixing blocks are arranged in parallel and connected with the hand-operated single-track ball screw sliding table, and the second fixing block is detachable and fixed on the mass On the first block, the second fixed block is located between the two fixed blocks 1. A permanent magnet is installed on the upper and lower sides of the fixed block 2, and a permanent magnet is installed on the side of the two fixed blocks facing the fixed block 2. Four permanent magnets The center of is on a vertical line, resulting in a negative stiffness term;

The hand-operated single-track ball screw slide table changes the distance between the four permanent magnets by manually operating the handwheel and replacing the second fixed block with different heights and the two fixed blocks with different relative distances. stiffness term.

Preferably, it also includes an I-shaped groove slideway, an I-shaped groove slider, and a fixing block three, the I-shaped groove slider is fixed on the bottom of the base through the through hole on the base, and the I-shaped groove slides The block cooperates with the I-shaped groove slideway and slides on the I-shaped groove slideway, the fixing block 3 is fixed on the base, the vibration platform is replaced by a vibration exciter, and the top rod of the vibration exciter is Connected with the fixed block three, the vibration exciter excites the base to vibrate through the fixed block three.

Preferably, the two fixed blocks are arranged in an "F" shape through a vertical rod, and the lower end of the vertical rod is connected to the hand-operated single-track ball screw sliding table, and the distance between the two fixed blocks is L, The fixed block 1 of different L is combined with the fixed block 2 of different heights to change the distance between the four permanent magnets, thereby changing the negative stiffness term.

Preferably, the base, the first mass block, the second mass block, the first fixed block and the second fixed block are all acrylic plates.

Preferably, the third fixed block is an acrylic plate.

Preferably, the length of the first manganese steel sheet is 0.15m, the length of the second manganese steel sheet is 0.3m, and the length of the I-shaped groove slideway is 0.3m.

Preferably, the I-shaped groove slideway and the I-shaped groove sliding block are made of aluminum alloy materials.

Acrylic plate members can eliminate the influence of permanent magnets on rigid members. First, when the vertical distance between the outer two magnets and the middle magnet is smaller, the gravitational force is stronger. Secondly, when the centers of the outer two permanent magnets and the middle two permanent magnets are on the same vertical line, the minimum stiffness occurs, and at this position, due to the symmetry of the repulsive force between the magnets, the mass is in a state of equilibrium. When the relative displacement of the center points of the upper two permanent magnets and the middle two permanent magnets on the horizontal line reaches a certain value, the stiffness is positive. When the vertical distance between the outer two magnets and the middle magnet is wider, the force acting on the slider that fixes the outer two permanent magnets is smaller, thus producing less resistance to the slider fixing the middle two permanent magnets. This creates a small area of negative stiffness.

Compared with the prior art, the advantages of the utility model are: the utility model can meet the various demands of the laboratory for the negative stiffness vibration absorber, improve the utilization rate, reduce the cost, and can change the negative stiffness of the system by changing the relative displacement of the permanent magnet. The stiffness item can also be installed and removed to make the negative stiffness dynamic vibration absorber perform the vibration reduction experiment of the negative stiffness dynamic vibration absorber in the two working environments of the vibration platform or the vibration exciter by installing and removing the I-shaped groove slideway and the I-shaped groove slider. , to meet the requirements of precision experiments of vibration and optics.

Description of drawings

The accompanying drawings described here are used to provide a further understanding of the present utility model and constitute a part of the present utility model. The schematic embodiments of the present utility model and their descriptions are used to explain the present utility model and do not constitute an improper limitation to the present utility model. .

Fig. 1 is the overall structure schematic diagram of the preferred embodiment of the present utility model;

2 is a side view of the overall structure of the preferred embodiment of the present invention;

3 is a schematic structural diagram of the I-shaped groove slideway according to the preferred embodiment of the present invention;

4 is a schematic structural diagram of an I-shaped groove slider according to a preferred embodiment of the present invention;

5 is a schematic diagram of an experimental device using a vibration exciter as an excitation source in a preferred embodiment of the present invention;

FIG. 6 is a schematic diagram of an experimental device using a vibration excitation platform as an excitation source in a preferred embodiment of the present invention;

Attached notes:

1, base, 2, permanent magnet, 3, mass block one, 4, mass block two, 5, manganese steel sheet one, 6, manganese steel sheet two, 7, hand-operated single-track ball screw slide table, 8 , Fixed block one, 9, fixed block two, 10, cylindrical linear guide rail, 11, I-shaped groove slideway, 12, I-shaped groove slider, 13, fixed block three, 14, vibration exciter, 15, vibration platform.

Detailed ways

The present utility model will be further described below with reference to the accompanying drawings and specific embodiments, but not as a limitation of the present utility model.

As shown in Figures 1 and 2, a negative stiffness dynamic vibration absorber based on permanent magnets includes a base 1, a dynamic vibration absorption device, a liftable clamping device, and four permanent magnets 2;

The base 1 is provided with a through hole, and the through hole is used to fix the base 1 on a vibration platform, and the vibration platform excites the base 1 to vibrate;

The dynamic vibration absorption device includes a mass block 1 3 and a mass block 2 4, the mass block 1 3 and the mass block 2 4 are connected by a manganese steel sheet 1 5 and screws, and the mass block 1 3 and the base 1 are connected. The two are connected by manganese steel sheet two 6 and screws, and the mass block two 4 is located between the mass block one 3 and the base 1;

The liftable clamping device includes a hand-cranked single-track ball screw slide table 7, a cylindrical linear guide rail 10, two fixed blocks 1 8 and two fixed blocks 9. The cylindrical linear guide rails 10 are arranged in parallel on the hand crank. One side of the hand-operated single-track ball screw slide table 7, the cylindrical linear guide 10 is provided with a sliding block with a lock, and two fixed blocks 8 are arranged in parallel and connected with the hand-operated single-track ball screw slide table 7 , the second fixed block 9 is detachably fixed on the mass block one 3, the fixed block two 9 is located between the two fixed blocks one 8, and a permanent magnet 2 is installed on the upper and lower sides of the fixed block two 9. The two fixed blocks one 8 face A permanent magnet 2 is installed on one side of the fixed block two 9, and the centers of the four permanent magnets 2 are on a vertical line, thereby generating a negative stiffness term;

The hand-cranked single-track ball screw slide table 7 changes the distance between the four permanent magnets by manually operating the handwheel and replacing the fixed blocks 2 9 with different heights and the two fixed blocks 1 8 with different relative distances. This changes the negative stiffness term.

Preferably, as shown in FIGS. 3-5 , it also includes an I-shaped groove slideway 11 , an I-shaped groove sliding block 12 , and a third fixing block 13 , and the I-shaped groove sliding block 12 passes through the through hole on the base 1 . Fixed on the bottom of the base 1 , the I-shaped groove slider 12 cooperates with the I-shaped groove slideway 11 and slides on the I-shaped groove slideway 11 , and the fixing block 3 13 is fixed on the base 1 . Above, the vibration platform is replaced by a vibration exciter, the top rod of the vibration exciter is connected with the fixing block 3 13 , and the vibration exciter excites the base 1 to vibrate through the fixing block 3 13 . Among them, the I-shaped groove slideway 11 is fixed on a non-vibrating experimental platform.

Preferably, the two fixing blocks 1 8 are arranged in an "F" shape through a vertical rod, and the lower end of the vertical rod is connected to the hand-operated single-track ball screw sliding table 7. The distance between the two fixing blocks 1 8 For L1, the fixed block one 8 of different L1 is combined with the fixed block two 9 of different heights to change the distance between the four permanent magnets, thereby changing the negative stiffness term.

Preferably, the base 1, the first mass block 3, the second mass block 4, the first fixing block 8, and the second fixing block 9 are all acrylic plates.

Preferably, the third fixed block 13 is an acrylic plate.

Preferably, the length of the first manganese steel sheet 5 is 0.15m, the length of the second manganese steel sheet 6 is 0.3m, and the length of the I-shaped groove slideway 11 is 0.3m.

Preferably, the I-shaped groove slideway 11 and the I-shaped groove sliding block 12 are made of aluminum alloy materials. Aluminum alloy material has the advantages of light weight, high strength, high rigidity and durability. Acrylic plate members can eliminate the influence of permanent magnets on rigid members. First, when the vertical distance between the outer two magnets and the middle magnet is smaller, the gravitational force is stronger. Secondly, when the centers of the outer two permanent magnets and the middle two permanent magnets are on the same vertical line, the minimum stiffness occurs, and at this position, due to the symmetry of the repulsive force between the magnets, the mass is in a state of equilibrium. When the relative displacement of the center points of the upper two permanent magnets and the middle two permanent magnets on the horizontal line reaches a certain value, the stiffness is positive. When the vertical distance between the outer two magnets and the middle magnet is wider, the force acting on the slider that fixes the outer two permanent magnets is smaller, thus producing less resistance to the slider fixing the middle two permanent magnets. This creates a small area of negative stiffness.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the implementation and protection scope of the present invention. Those skilled in the art should be able to realize that any application of the description and illustrations of the present invention has The solutions obtained from equivalent substitutions and obvious changes should be included in the protection scope of the present invention.

Claims (7)

1. a negative stiffness dynamic vibration absorber based on permanent magnets, is characterized in that, comprises base (1), dynamic vibration absorption device, can lift clamping device, four permanent magnets (2); The base (1) is provided with a through hole, and the through hole is used to fix the base (1) on a vibration platform, and the vibration platform excites the base (1) to vibrate; The dynamic vibration absorption device includes a mass block one (3) and a mass block two (4), and the mass block one (3) and the mass block two (4) are connected by a manganese steel sheet one (5) and a screw, so the The mass block one (3) and the base (1) are connected by manganese steel sheet two (6) and screws, and the mass block two (4) is located between the mass block one (3) and the base (1). ; The liftable clamping device includes a hand-cranked single-track ball screw slide table (7), a cylindrical linear guide rail (10), two fixed blocks one (8), and two fixed blocks (9). (10) are arranged in parallel on one side of the hand-operated single-track ball screw slide table (7), the cylindrical linear guide rail (10) is provided with a sliding block with a lock, and two fixed blocks one (8) are arranged in parallel and is connected with the hand-operated single-track ball screw slide table (7), the second fixed block (9) is detachably fixed on the mass block one (3), and the second fixed block (9) is located on the two fixed blocks one ( 8), a permanent magnet (2) is installed on the upper and lower sides of the second fixed block (9), and a permanent magnet (2) is installed on the side of the two fixed blocks (8) facing the second fixed block (9). The centers of the four permanent magnets (2) are on a vertical line, resulting in a negative stiffness term; The hand-cranked single-track ball screw slide table (7) changes the four permanent blocks by manually operating the handwheel and replacing the second fixed block (9) with different heights and the two fixed blocks with different relative distances (8). The distance between the magnets, thus changing the negative stiffness term. 2. The negative stiffness dynamic vibration absorber based on permanent magnet according to claim 1, characterized in that, further comprising an I-shaped groove slideway (11), an I-shaped groove sliding block (12), a fixed block three (13), The I-slot slider (12) is fixed on the bottom of the base (1) through the through hole on the base (1), and the I-slot slider (12) is connected to the I-slot slideway (11). ) and slide on the I-shaped groove slideway (11), the fixing block three (13) is fixed on the base (1), the vibration platform is replaced by a vibration exciter, the vibration excitation The top rod of the exciter is connected with the fixed block three (13), and the vibration exciter excites the base (1) to vibrate through the fixed block three (13). 3. The negative stiffness dynamic vibration absorber based on permanent magnets according to claim 1, characterized in that, the two fixed blocks one (8) are arranged in an "F" shape through a vertical rod, and the lower end of the vertical rod is connected to a hand-crank type. The single-track ball screw slide table (7) is connected, the distance between the two fixed blocks one (8) is L1, the fixed block one (8) of different L1 is combined with the fixed block two (9) of different heights, changing The distance between the four permanent magnets, thereby changing the negative stiffness term. 4. The negative stiffness dynamic vibration absorber based on permanent magnets according to claim 1, wherein the base (1), the mass one (3), the mass two (4), the fixed block one (8) ) and two (9) fixed blocks are acrylic plates. 5 . The negative stiffness dynamic vibration absorber based on permanent magnets according to claim 2 , wherein the third fixed block ( 13 ) is an acrylic plate. 6 . 6. The negative stiffness dynamic vibration absorber based on permanent magnet according to claim 2, wherein the length of the first manganese steel sheet (5) is 0.15m, and the length of the second manganese steel sheet (6) is 0.3m , the length of the I-shaped groove slideway (11) is 0.3m. 7 . The negative stiffness dynamic vibration absorber based on permanent magnet according to claim 2 , wherein the I-shaped groove slideway ( 11 ) and the I-shaped groove sliding block ( 12 ) are made of aluminum alloy material. 8 .

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