阅读说明：本技术 一种基于双稳态折纸的扭转振动吸振器单元及吸振器 (Torsional vibration absorber unit based on bistable folded paper and vibration absorber ) 是由 庄国志 许著龙 王瑜琪 于 2021-07-29 设计创作，主要内容包括：本发明公开了一种基于双稳态折纸的扭转振动吸振器单元及吸振器。所述吸振器由多个扭转振动吸振器单元周期排列组成,吸振器单元包括Kresling振子和两个非对称布置的质量块,所述的质量块非对称地设置Kresling振子的顶面上；所述的Kresling振子的上下底面均为正n多边形,其中n为偶数,且Kresling振子的高度大于正n多边形的外接圆半径,Kresling振子具有双稳态。本发明结构简单,可以根据实际情况,在两个稳定的状态之间进行切换,从而调节需要抑制的振动频率,而且,由于本发明结构的非对称布置,振子对于扭转振动敏感,可以产生明显的扭转振动抑制效果。(The invention discloses a torsional vibration absorber unit based on bistable folding paper and a vibration absorber. The vibration absorber is formed by periodically arranging a plurality of torsional vibration absorber units, each vibration absorber unit comprises a Kresling vibrator and two mass blocks which are asymmetrically arranged, and the mass blocks are asymmetrically arranged on the top surface of the Kresling vibrator; the upper bottom surface and the lower bottom surface of the Kresling vibrator are both regular n polygons, wherein n is an even number, the height of the Kresling vibrator is larger than the radius of a circumscribed circle of the regular n polygons, and the Kresling vibrator has a bistable state. The invention has simple structure, can switch between two stable states according to actual conditions, thereby adjusting the vibration frequency to be inhibited, and can generate obvious torsional vibration inhibiting effect because the vibrators are sensitive to torsional vibration due to the asymmetrical arrangement of the structure.)

1. A torsional vibration absorber unit based on bistable origami is characterized by comprising a Kresling oscillator and two mass blocks which are asymmetrically arranged, wherein the top surface and the bottom surface of the Kresling oscillator are both regular n polygons, n is an even number, the mass blocks are arranged on the top points of the top surface of the Kresling oscillator, and the two mass blocks are asymmetric about any symmetry axis of the regular n polygons on the bottom surface of the Kresling oscillator; the height of the Kresling transducer, which is bistable and in one of its stable states, is greater than the radius of the circumcircle of the regular n-polygon.

2. The preferred bistable origami-based torsional vibration absorber unit of claim 1, wherein said two masses are of the same mass and volume.

3. The preferred bistable origami-based torsional vibration absorber unit of claim 1, wherein said Kresling transducer is in point contact with the proof mass.

4. The preferred bistable origami-based torsional vibration absorber unit of claim 3 wherein said mass is a sphere.

5. The preferred bistable origami-based torsional vibration absorber unit of claim 1, wherein the mass of the proof mass is 20-50 times the mass of the Kresling vibrator.

6. A bistable origami-based torsional vibration absorber comprising a plurality of torsional vibration absorber units according to any one of claims 1 to 5, arranged in a periodic array or arrangement in an equally spaced manner. The number of the torsional vibration absorber units is more than or equal to 6.

7. The bistable origami-based torsional vibration absorber of claim 6 wherein each torsional vibration absorber unit is in a stable state that may be the same or different.

8. The bistable origami-based torsional vibration absorber of claim 6 wherein each torsional vibration absorber unit is switchable in its stable state.

Technical Field

The invention belongs to the field of torsional vibration absorbers, and particularly relates to a torsional vibration absorber unit based on bistable folding paper and a vibration absorber.

Background

Mechanical vibration is widely used in various fields such as aerospace, machine manufacturing, and civil engineering, and mechanical vibration significantly reduces the reliability and the life of a structure, and therefore vibration control is an important issue in the field of engineering technology. Torsional vibrations are inevitable due to the wide variety of eccentric excitations that exist in engineering practice.

The known vibration absorber units usually have a significant damping effect against bending or longitudinal vibrations and a less significant absorption effect against torsional vibrations, since the vibration absorber units are not sensitive to torsional vibrations. On the other hand, because the operating mode in the engineering reality is more complicated, under the operating mode circumstances of difference, the operating frequency that the structure corresponds will have the difference, and traditional dynamic vibration absorber unit can't carry out the switching of the frequency that needs to restrain according to actual conditions, consequently has certain limitation.

Disclosure of Invention

The invention provides an asymmetric bistable torsional dynamic vibration absorber unit based on Kresling origami and a vibration absorber, aiming at the problems that the existing vibration absorber unit is not suitable for inhibiting torsional vibration and is difficult to adapt to different vibration environments. The invention has simple structure, can switch between two stable states according to actual conditions, thereby adjusting the vibration frequency to be inhibited, and can generate obvious torsional vibration inhibiting effect because the vibrators are sensitive to torsional vibration due to the asymmetrical arrangement of the structure.

The technical scheme of the invention is as follows:

the invention provides a torsional vibration absorber unit based on bistable origami, which comprises a Kresling vibrator and two mass blocks which are asymmetrically arranged, wherein the Kresling vibrator comprises the Kresling vibrator and the two mass blocks which are asymmetrically arranged, the top surface and the bottom surface of the Kresling vibrator are both regular n polygons, n is an even number, the mass blocks are arranged on the top points of the top surface of the Kresling vibrator, and the two mass blocks are asymmetric about any symmetry axis of the regular n polygons on the bottom surface of the Kresling vibrator; the height of the Kresling transducer, which is bistable and in one of its stable states, is greater than the radius of the circumcircle of the regular n-polygon.

Preferably, the Kresling oscillator can be made of low-density materials such as plastics and aluminum, the mass blocks are made of high-density metal materials such as iron and copper, and the materials, the masses and the volumes of the two mass blocks are the same.

Preferably, the contact between the Kresling oscillator and the mass block is point contact. Furthermore, the mass block is a sphere, and the bonding mode can be glue bonding or welding.

The asymmetric arrangement of the masses is more sensitive to torsional vibrations and can therefore better suppress torsional vibrations.

The vibration absorber units are bistable, so that the working frequency can be switched according to the actual condition, and the vibration absorber units in different states can be combined and arranged according to the actual condition.

The mass of the mass is chosen in relation to the frequency range to be suppressed and should be significantly larger than the mass of the Kresling transducer, typically but not limited to, e.g. 20-50 times the mass of the Kresling transducer.

The invention also provides a torsional vibration absorber based on bistable folding paper, which comprises a plurality of torsional vibration absorber units, wherein the torsional vibration absorber units are arranged in a plane periodic array or in a straight line in an equidistant mode. The number of the torsional vibration absorber units is more than or equal to 6.

Preferably, the arrangement pitch of the torsional vibration absorber units is selected according to the frequency range to be suppressed.

Preferably, the Kresling vibrators of each torsional vibration absorber unit in the torsional vibration absorber may be in the same stable state as each other or in different stable states, and the frequency to be suppressed may be switched between the two stable states as needed.

The invention has the beneficial effects that:

the vibration absorber is simple in structure, the change of the resonance frequency of the vibration absorber can be realized by only switching the Kresling vibrator between two states on the premise of not replacing structural components, the vibration absorber is more sensitive to torsional vibration due to the asymmetrical arrangement of the structure, and the torsional vibration can be more effectively inhibited.

Drawings

Fig. 1 is a schematic structural view of a torsional vibration absorber unit of the present invention:

FIG. 2 is a schematic view of an asymmetric arrangement of top mass blocks about a bottom symmetry axis;

figure 3 shows a first arrangement of the torsional vibration absorber unit on the beam according to an embodiment of the invention:

figure 4 shows a second arrangement of the torsional vibration absorber unit on the beam according to an embodiment of the invention:

figure 5 shows a third arrangement of the torsional vibration absorber unit on the beam according to an embodiment of the invention:

figure 6 is a frequency response curve for different torsional vibration absorber unit arrangements;

1-Kresling transducer; 2-a mass block; 3-beam to be damped.

Detailed Description

Note that the application examples described herein are only a part of the embodiments of the present invention, and not all embodiments.

The structure of the torsional vibration absorber unit of this embodiment is shown in fig. 1, and includes a bistable Kresling vibrator 1 (in this embodiment, the material is origami, and the top surface and the bottom surface are both regular hexagonal structures, that is, n is 6), and two mass blocks 2 (the mass blocks of this embodiment are spheres, and the material is steel balls). The two steel balls are fixed on two opposite vertexes of the top surface of the Kresling vibrator and are asymmetric about any symmetric axis of a regular hexagon on the bottom surface of the Kresling vibrator; the position of the steel ball can be changed along with the compression of Kresling folded paper, so that the band gap of the torsional wave is regulated and controlled. Meanwhile, due to the asymmetric arrangement of the mass blocks, the torsional wave band gap with wider and lower frequency can be realized by utilizing the coupling of the elastic waves.

In addition to the configuration already given in the present invention, the geometry of the Kresling origami can be chosen to be other regular polygons, but the number of sides of a regular polygon is required to be even. The two mass blocks are arranged on the top point of the top surface of the Kresling oscillator, and are asymmetric about any symmetry axis of a regular n-shaped polygon on the bottom surface of the Kresling oscillator; as shown in fig. 1 and 2, the height of the Kresling transducer is greater than the radius of the circumscribed circle of the regular n-polygon. The Kresling vibrator has bistable states and is in one of the stable states, and richer band gap adjusting effects can be realized by combining and arranging the vibration absorber units in different stable states.

The unit structure shown in fig. 1 is arranged on an aluminum beam 3 to be damped to form the torsional vibration absorber, as shown in fig. 3-5, the unit structure is uniformly arranged in 8 cycles, the length of each cycle unit is 100mm, and the unit structures are arranged in a straight line. In this case, the parameters of the aluminum beam are 32mm by 3mm by 800mm, in this case, the material of the Kresling oscillator is selected to be paper, and the material of the mass block is selected to be steel. Considering the arrangement of three different cases, respectively (1) eight absorber units are all in the first stable state, shown in figure 3; (2) the first four vibration absorber units are in a first stable state, and the last four vibrators are in a second stable state, which is shown in fig. 4; (3) the eight shock absorber units are in the second stable state, shown in figure 5. The Kresling vibrator has a bistable state, wherein the first stable state means that the Kresling vibrator is in a high-height state; the second steady state is a state in which the Kresling transducer is at a low height. In different states of the Kresling vibrator, the stiffness and the concentrated mass of the vibration absorber unit are different compared with the position of the beam, but the Kresling vibrator is still a 'spring-mass' system, so that in three cases, the structure has the torsional vibration absorption effect, but the corresponding working frequency ranges are different.

3-5, the finite element simulation conditions of the torsional vibration excitation on one side and the displacement response on the other side are shown in FIG. 6, and it can be found from FIG. 6 that the band gap positions of the torsional waves are changed as the torsional vibration absorber units are arranged in different states, and the band gap frequencies of the case (1) are 150-200Hz,310-390Hz and 430-567 Hz; the band gap frequency of the case (2) is 135-172Hz, 320-402 Hz; the band gap frequency of the case (3) is 280-350Hz, which shows that the Kresling oscillators of each unit can be switched and selected between two stable states according to the frequency to be suppressed, so as to achieve the effect of regulating and controlling the torsional vibration according to the actual situation.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.