阅读说明：本技术 一种自适应阶次跟踪减振超材料轴结构 (Self-adaptive order tracking vibration reduction metamaterial shaft structure ) 是由 任霞光 吴昱东 丁渭平 杨明亮 崔展豪 于 2021-10-20 设计创作，主要内容包括：本发明公开了一种自适应阶次跟踪减振超材料轴结构,包括轴基体、壳体和晶胞单元,晶胞单元包括定刚度弹簧、质量块和变刚度弹簧,质量块通过定刚度弹簧分别与轴基体和壳体相连,相邻质量块之间通过变刚度弹簧相连。质量块的数量为八个且呈环状分布在轴基体四周,定刚度弹簧的数量为十六个,变刚度弹簧的数量为八个。本发明所提供的一种自适应阶次跟踪减振超材料轴结构具有低频隔振能力,沿轴结构周向设计不同厚度的质量块,产生多个不同的带隙,组合形成较宽的低频带隙。能够实现自适应阶次跟踪,随着转速的改变,形成的低频禁带也会跟着变化,减振降噪效果更好。(The invention discloses a self-adaptive order tracking vibration reduction metamaterial shaft structure which comprises a shaft base body, a shell and a unit cell unit, wherein the unit cell unit comprises a fixed stiffness spring, mass blocks and a variable stiffness spring, the mass blocks are respectively connected with the shaft base body and the shell through the fixed stiffness spring, and adjacent mass blocks are connected through the variable stiffness spring. The number of the mass blocks is eight, the mass blocks are annularly distributed around the shaft base body, the number of the constant stiffness springs is sixteen, and the number of the variable stiffness springs is eight. The self-adaptive order tracking vibration reduction metamaterial shaft structure provided by the invention has low-frequency vibration isolation capability, the mass blocks with different thicknesses are designed along the circumferential direction of the shaft structure, a plurality of different band gaps are generated, and a wider low-frequency band gap is formed by combination. The self-adaptive order tracking can be realized, the formed low-frequency forbidden band can be changed along with the change of the rotating speed, and the vibration and noise reduction effect is better.)

1. The utility model provides a damping metamaterial shaft structure is trailed to self-adaptation order which characterized in that: the unit cell unit comprises a fixed stiffness spring (3), mass blocks (4) and a variable stiffness spring (5), wherein the mass blocks (4) are respectively connected with the shaft base body (1) and the shell (2) through the fixed stiffness spring (3), and adjacent mass blocks (4) are connected through the variable stiffness spring (5).

2. The adaptive order tracking damped metamaterial shaft structure as claimed in claim 1, wherein: the number of the mass blocks (4) is eight, the mass blocks are annularly distributed around the shaft base body (1), the number of the fixed stiffness springs (3) is sixteen, and the number of the variable stiffness springs (5) is eight.

3. The adaptive order tracking damped metamaterial shaft structure as claimed in claim 1, wherein: the shaft base body (1) and the shell (2) are both made of metal materials.

4. The adaptive order tracking damped metamaterial shaft structure as claimed in claim 1, wherein: the mass (4) is made of steel.

5. The adaptive order tracking damped metamaterial shaft structure as claimed in claim 1, wherein: the constant stiffness spring (3) and the variable stiffness spring (5) are both made of alloy spring steel.

6. The adaptive order tracking damped metamaterial shaft structure as claimed in claim 1, wherein: the two ends of the constant stiffness spring (3) are provided with constant stiffness spring hooks, the two ends of the variable stiffness spring (5) are provided with variable stiffness spring hooks, a shaft base body hole is formed in the shaft base body (1), a shell body hole is formed in the shell body (2), and a mass block hole is formed in the mass block (4); the shaft base body hole is internally provided with a fixed stiffness spring hook in a penetrating way, the shell body hole is internally provided with a fixed stiffness spring hook in a penetrating way, and the mass block hole is internally provided with a fixed stiffness spring hook and a variable stiffness spring hook in a penetrating way.

7. The adaptive order tracking damped metamaterial shaft structure as claimed in claim 1, wherein: the shaft base body (1) is of a sleeve-shaped structure and can be fixed on a target part through matching, and the inner diameter and the outer diameter of the shaft can be designed according to actual use scenes.

8. The adaptive order tracking damped metamaterial shaft structure as claimed in claim 1, wherein: the two mass blocks (4) which are symmetrically arranged by taking the shaft base body (1) as the center form a mass block group, and the shape of each mass block (4) is a cuboid, a cube or a sector.

9. The adaptive order tracking damped metamaterial shaft structure as claimed in claim 1, wherein: the thickness of the mass blocks (4) in the mass block group is the same, so that dynamic balance is guaranteed.

10. The adaptive order tracking damped metamaterial shaft structure as claimed in claim 8, wherein: the thickness of each group of mass blocks (4) is different so as to widen the band gap.

Technical Field

The invention belongs to the technical field of crossing of vibration noise control and functional composite materials, and particularly relates to a self-adaptive order tracking vibration reduction metamaterial shaft structure.

Background

With respect to NVH performance of rotary machines, torsional vibration of rotating parts such as engine crankshafts and transmission shafts has been a concern. Torsional vibration can cause corresponding NVH and fatigue problems, for example, torsional vibration of an automobile can cause fatigue of teeth and tooth surfaces of meshing gears, elastic couplings and the like, and cause vibration of a steering wheel, a seat and a pedal, so that the problem of vibration comfort is caused. Torsional vibration can also cause corresponding noise problems such as engine start-stop noise, drive shaft resonance induced in-vehicle noise, transmission gear mesh noise, and the like. In addition to causing NVH and fatigue problems, torsional vibration can also reduce product performance, such as reducing fuel economy of the vehicle, among other problems. Therefore, it is important for the rotating structure to isolate or reduce the torsional vibration.

By additionally arranging the traditional torsion damper, the natural frequency of the damper is controlled to be matched with the resonance frequency of the transmission shaft, and the problem of vibration noise of a rotating structure can be solved or reduced to a certain degree. At present, a fixed-frequency torsional vibration damper is used in domestic markets, namely the frequency of torsional vibration which can be blocked by the vibration damper after the design of the vibration damper is finished is determined and cannot be changed. However, in practical situations, the vibration frequency of the rotating component changes along the order line with the change of the rotating speed, so that a shaft structure capable of tracking the order is required to achieve a better vibration isolation effect.

Disclosure of Invention

The invention aims to solve the problems and provides a self-adaptive order tracking damping metamaterial shaft structure which can realize order tracking in a certain frequency range and has a good damping effect.

In order to solve the technical problems, the technical scheme of the invention is as follows: a self-adaptive order tracking vibration reduction metamaterial shaft structure comprises a shaft base body, a shell and a unit cell unit, wherein the unit cell unit comprises a fixed stiffness spring, mass blocks and variable stiffness springs, the mass blocks are respectively connected with the shaft base body and the shell through the fixed stiffness springs, and adjacent mass blocks are connected through the variable stiffness springs.

Preferably, the number of the mass blocks is eight, the mass blocks are annularly distributed around the shaft base body, the number of the constant stiffness springs is sixteen, and the number of the variable stiffness springs is eight.

Preferably, the shaft base and the housing are both made of a metal material.

Preferably, the mass is made of steel.

Preferably, the constant stiffness spring and the variable stiffness spring are both made of alloy spring steel.

Preferably, the two ends of the constant stiffness spring are provided with constant stiffness spring hooks, the two ends of the variable stiffness spring are provided with variable stiffness spring hooks, the shaft base is provided with a shaft base hole, the shell is provided with a shell hole, and the mass block is provided with a mass block hole; the shaft base body hole is internally provided with a fixed stiffness spring hook in a penetrating way, the shell body hole is internally provided with a fixed stiffness spring hook in a penetrating way, and the mass block hole is internally provided with a fixed stiffness spring hook and a variable stiffness spring hook in a penetrating way.

Preferably, the shaft base body is of a sleeve-shaped structure and can be fixed on a target part through matching, and the inner diameter and the outer diameter of the shaft can be designed according to actual use scenes.

Preferably, the two mass blocks symmetrically arranged by taking the shaft substrate as the center form a mass block group, and the shape of the mass block is a cuboid, a cube or a sector.

Preferably, the thicknesses of the mass blocks in the mass block group are the same, so that dynamic balance is ensured.

Preferably, the masses of each set have different thicknesses to widen the band gap.

The invention has the beneficial effects that:

1. the self-adaptive order tracking vibration reduction metamaterial shaft structure provided by the invention has low-frequency vibration isolation capability, the mass blocks with different thicknesses are designed along the circumferential direction of the shaft structure, a plurality of different band gaps are generated, and a wider low-frequency band gap is formed by combination.

2. The invention can realize self-adaptive order tracking, and the torsional vibration frequency of the rotating part can change along with the change of the rotating speed. Meanwhile, the rigidity of the metamaterial shaft structure can be changed under the action of centrifugal force, and a formed low-frequency forbidden band can be changed along with the rigidity, so that torsional vibration can be well isolated at different rotating speeds, and the vibration reduction and noise reduction effects are better.

3. The springs and the mass blocks are uniformly distributed along the circumferential direction, so that the problem of serious dynamic unbalance cannot be caused for a high-speed rotating shaft structure, and the dynamic balance is good.

4. The structure of the invention occupies small space, and the inner diameter and the outer diameter of the shaft base body can be designed according to the actual use scene, and the invention is easy to install, has wide application range, and can be used for reducing, isolating and controlling low-frequency torsional vibration and low-frequency noise in equipment such as automobiles, trains, ships, airplanes and the like.

Drawings

FIG. 1 is a schematic diagram of the overall structure of an adaptive order tracking damped metamaterial shaft structure of the present invention.

Fig. 2 is a schematic half-section of the overall structure of the present invention.

Fig. 3 is a side view of the overall structure of the present invention.

Fig. 4 is a schematic view of a sectional structure B-B of fig. 3 in a medium-speed rotation state.

Fig. 5 is a schematic view of a cross-sectional structure B-B in fig. 3 in a high-speed rotation state.

Fig. 6 is a schematic view of a cross-sectional view B-B in fig. 3 in a low-speed rotation state.

Description of reference numerals: 1. a shaft base body; 2. a housing; 3. a constant stiffness spring; 4. a mass block; 5. a variable rate spring.

Detailed Description

The invention is further described with reference to the following figures and specific embodiments:

as shown in fig. 1 to 6, the adaptive order tracking vibration damping metamaterial shaft structure provided by the present invention includes a shaft base 1, a housing 2 and a unit cell unit, wherein the unit cell unit includes a constant stiffness spring 3, a mass block 4 and a variable stiffness spring 5, the mass block 4 is respectively connected with the shaft base 1 and the housing 2 through the constant stiffness spring 3, and adjacent mass blocks 4 are connected through the variable stiffness spring 5.

In the present embodiment, the number of the mass blocks 4 is eight, and the mass blocks are annularly distributed around the shaft base 1, the number of the constant stiffness springs 3 is sixteen, and the number of the variable stiffness springs 5 is eight. In the actual use process, the number of the mass blocks 4 can be increased and decreased according to the use requirement, and the number of the constant stiffness springs 3 and the variable stiffness springs 5 is correspondingly increased and decreased. The mass blocks 4 are uniformly distributed along the circumference of the shaft structure of the shaft base body 1.

The shaft base body 1 is positioned in the shell 2, an annular space is formed between the shaft base body 1 and the shell 2, and the mass blocks 4 are distributed in the annular space. Rotating parts are arranged inside the shaft base body 1 in a penetrating mode and can rotate for existing mature technology equipment. The rotation of the rotary part drives the shaft base 1 to rotate.

In this embodiment, the shaft base 1 is a sleeve, and can be fixed to a target member by fitting, and both the inner diameter and the outer diameter of the shaft can be designed according to actual use scenarios. The shaft base body 1 and the housing 2 are both made of a metal material, and the mass 4 is made of steel. The constant stiffness spring 3 and the variable stiffness spring 5 are both made of alloy spring steel.

The two ends of the constant stiffness spring 3 are provided with constant stiffness spring hooks, the two ends of the variable stiffness spring 5 are provided with variable stiffness spring hooks, the shaft base 1 is provided with a shaft base hole, the shell 2 is provided with a shell hole, and the mass block 4 is provided with a mass block hole; the shaft base body hole is internally provided with a fixed stiffness spring hook in a penetrating way, the shell body hole is internally provided with a fixed stiffness spring hook in a penetrating way, and the mass block hole is internally provided with a fixed stiffness spring hook and a variable stiffness spring hook in a penetrating way. The shaft base body 1, the shell 2, the constant stiffness spring 3, the mass block 4 and the variable stiffness spring 5 can be firmly connected in the using process and do not fall off in the way that the constant stiffness spring hook and the variable stiffness spring hook are connected with the shaft base body hole, the shell hole and the mass block hole.

The shaft base body 1 is of a sleeve-shaped structure, can be fixed on a target part through matching, and the inner diameter and the outer diameter of the shaft can be designed according to actual use scenes.

Two mass blocks 4 symmetrically arranged by taking the shaft base body 1 as a center form a mass block group, and the shape of each mass block 4 is a cuboid, a cube or a sector.

In this embodiment, the thicknesses of the mass blocks 4 in the mass block group are the same, so as to ensure dynamic balance. In practical use, the thickness of each set of mass blocks 4 may also be different to widen the band gap. The thickness of the quality block 4 can be changed in a targeted manner according to different use requirements, so that the use requirements can be better met, and the practicability of the invention is improved.

As shown in fig. 5 and 6, adjacent masses 4 are connected in series through variable stiffness springs 5, an external existing rotating component drives the shaft base 1 to rotate, when the rotating speed of the rotating component changes, the masses 4 move along a radial direction under the action of centrifugal force, the distance between the masses 4 and the shaft base 1 changes, the variable stiffness springs 5 are stretched or compressed, the spring stiffness changes accordingly, the stiffness of the whole system changes, and the corresponding band gap of the whole system also moves.

The rotational speed of the rotating member is ω at which the centrifugal force equals the spring force, there is the formula mr ω²＝2K₁Δx_rWhere m is the mass of the mass block, r is the distance from the mass block to the center of rotation, k₁For constant rate spring stiffness, Δ x_rIs the displacement of the mass in the radial direction. According to the formula, the rigidity k of the constant-rigidity spring is designed₁Obtaining the radial displacement delta x of the spring under a certain rotating speed omega_r。

The relationship between the stiffness of the variable-stiffness spring and the elongation of the spring can be designed according to the actual engineering, and the relationship is set as k₂＝f(Δx_t) In the formula, Δ x_tElongation of the spring to be varied, k₂For a variable rate spring at an elongation of deltax_tCorresponding stiffness. The radial movement of the masses causes the variable rate spring to stretch or compress, the angle between each mass relative to the axis being 45, Δ x_tAnd Δ x_rThe following relationships exist: 2 Δ x_rsin22.5°＝Δx_t。

The two formulas are combined to obtain:namely, the relationship among the rotating component rotating speed, the constant stiffness spring stiffness and the variable stiffness spring stiffness is established. According to the rigidity k of the variable-rigidity spring₂And calculating to obtain the forbidden band of the whole system, and designing system parameters to obtain the expected forbidden band.

When the rotating speed changes, the process is repeated for each rotating speed, the expected forbidden band under each rotating speed can be obtained, the effect of well isolating torsional vibration under different rotating speeds can be achieved, and therefore order tracking is achieved.

It will be appreciated by those of ordinary skill in the art that the embodiments described herein are intended to assist the reader in understanding the principles of the invention and are to be construed as being without limitation to such specifically recited embodiments and examples. Those skilled in the art can make various other specific changes and combinations based on the teachings of the present invention without departing from the spirit of the invention, and these changes and combinations are within the scope of the invention.