Magnetorheological elastomer damper based on compression-torsion coupling mechanism

Abstract

The application discloses a kind of magnetorheological elastomer shock absorber based on compression-torsion coupling mechanism, comprising: upper end cover, lower end cover, intermediate connecting sheet, upper internal compression-torsion structure, lower internal compression-torsion structure, upper external compression-torsion structure, lower external compression-torsion structure;The upper end cover and lower end cover are rotatably connected;The intermediate connecting sheet is arranged between upper end cover and lower end cover;Upper internal compression-torsion structure, upper external compression-torsion structure are connected between upper end cover and intermediate connecting sheet, lower internal compression-torsion structure, lower external compression-torsion structure are arranged between lower end cover and intermediate connecting sheet;The upper and lower internal compression-torsion structure torsion is about the reverse fit of intermediate connecting sheet;The lower external compression-torsion structure is about the reverse fit of intermediate connecting sheet;The elastic modulus of upper and lower external compression-torsion structure is greater than the elastic modulus of upper and lower internal compression-torsion structure;The application can synergistic compression torsion effect to dissipate energy, thereby improve the damping efficiency.

Description

Technical Field

[0001] The invention relates to the field of vibration reduction, specifically a magnetorheological elastomer vibration damper based on a pressure-torsion coupling mechanism. Background Technology

[0002] Vibration damping and buffering of high-displacement vibrations is a crucial task in the mechanical industry, holding significant importance in automobiles, machine tools, and many other specific applications. In recent years, magnetorheological elastomers (MREs) with adjustable stiffness have found important applications in this field. Due to the sensitivity of MREs to magnetic fields caused by the arrangement of their internal magnetic particles, their elastic and shear moduli can be precisely modulated by an external magnetic field, avoiding resonance in mechanical systems under vibration excitation and ensuring system safety. Precise vibration sensing modules are essential during vibration damping. By sensing the frequency characteristics of external vibration excitation in real time, the optimal modulation magnetic field can be determined, adjusting the natural frequency of the mechanical system to its optimal state. However, current MRE-based vibration dampers often only utilize changes in their elastic modulus for vibration isolation, resulting in lower damping efficiency in the single-frequency domain compared to traditional rubber dampers. Therefore, significant efforts are needed to fully utilize the modulus variation characteristics of MREs to improve their vibration damping efficiency. Summary of the Invention

[0003] The purpose of this invention is to provide a magnetorheological elastomer (MRE) vibration damper based on a compression-torsion coupling mechanism, which can dissipate energy in conjunction with the compression and torsion action of the MRE, thereby improving the vibration damping efficiency; and it is designed with a triboelectric sensor based on rotation angle triggering, which can realize the monitoring of vibration frequency and amplitude.

[0004] The technical solution to achieve the purpose of this invention is as follows:

[0005] A magnetorheological elastomer vibration damper based on a pressure-torsion coupling mechanism includes: an upper end cover, a lower end cover, an intermediate connecting piece, an upper internal pressure-torsion structure, a lower internal pressure-torsion structure, an upper external pressure-torsion structure, a lower external pressure-torsion structure, an Ecoflex electrode layer, and an electrode layer.

[0006] The upper end cover and the lower end cover are rotatably connected; the middle connecting piece is disposed between the upper end cover and the lower end cover and can rotate relative to the upper end cover and the lower end cover;

[0007] The upper internal pressure-torsion structure is connected between the upper end cover and the middle connecting piece, and the lower internal pressure-torsion structure is disposed between the lower end cover and the middle connecting piece; the upper internal pressure-torsion structure and the lower internal pressure-torsion structure have opposite torsional directions and are reverse-fitted with respect to the middle connecting piece;

[0008] The upper external pressure-torsion structure is connected between the upper end cover and the middle connecting piece, and the lower external pressure-torsion structure is disposed between the lower end cover and the middle connecting piece; the upper external pressure-torsion structure and the lower external pressure-torsion structure have opposite torsional directions and are reverse-fitted with respect to the middle connecting piece;

[0009] The torsional direction of the upper external pressure-torsion structure is the same as that of the upper internal pressure-torsion structure; the elastic modulus of the upper and lower external pressure-torsion structures is greater than that of the upper and lower internal pressure-torsion structures; the upper and lower internal pressure-torsion structures and the upper and lower external pressure-torsion structures are used to convert vertical vibration displacement into torsional deformation.

[0010] Both the upper internal compression-torsion structure and the lower internal compression-torsion structure are magnetorheological elastic bodies, which are used to dissipate vibration energy through changes in elastic modulus and shear modulus under the action of a magnetic field.

[0011] The electrode layer is disposed on the rotating part between the upper end cover and the lower end cover. The Ecoflex electrode layer is attached to the outside of the electrode layer and led out from the middle connecting piece for detecting the torsion angle.

[0012] The significant advantages of this invention compared to existing technologies are:

[0013] (1) The vibration damper of the present invention can convert vertical vibration displacement into torsional deformation of internal compression-torsion structure and external compression-torsion structure. Under the action of magnetic field, the vibration energy is dissipated by the changes in elastic modulus and shear modulus of MRE, thereby improving vibration damping efficiency. Furthermore, a triboelectric sensor is designed by gradually increasing the contact area between Ecoflex electrode layer and copper electrode layer during the torsion process, which can sense the torsion angle and monitor the vibration frequency and amplitude.

[0014] (2) The vibration damper is assembled with the vibration table via a coupling, the mass block is placed above the vibration damper, the acceleration sensor is placed above the mass block, and the external enclosure is used to limit the vibration damper, thus achieving high-performance adaptive buffering in a wide frequency band (0-20Hz). Attached Figure Description

[0015] Figure 1 This is a front view of the vibration damper of the present invention.

[0016] Figure 2 This is a cross-sectional view of the vibration damper of the present invention.

[0017] Figure 3 Internal parts of the vibration damper of this invention

[0018] Figure 4 This is a schematic diagram of the experimental test of the vibration damper of the present invention.

[0019] Figure 5 This is a waveform detection diagram of the triboelectric sensor for the vibration damper of the present invention.

[0020] Figure 6 The diagram shows the acceleration waveforms of the vibration damper before and after vibration reduction in this invention.

[0021] In the diagram: 1. Upper internal pressure-torsion structure; 2. Middle connecting piece; 3. Ecoflex electrode layer; 4. Copper electrode layer; 5. Lower internal pressure-torsion structure; 6. Upper end cover; 7. Upper external pressure-torsion structure; 8. Lower external pressure-torsion structure; 9. Lower end cover; 10. Vibration damper; 11. Vibration table; 12. Accelerometer; 13. Mass block; 14. Coupling. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1

[0025] Please see Figure 1 Figure 2 Figure 3This invention provides a magnetorheological elastomer vibration damper 10 based on a pressure-torsion coupling mechanism, comprising an upper internal pressure-torsion structure 1, a lower internal pressure-torsion structure 5, an upper external pressure-torsion structure 7, a lower external pressure-torsion structure 8, an intermediate connecting piece 2, an upper end cover 6, a lower end cover 9, an Ecoflex electrode layer 3, and a copper electrode layer 4; the upper internal pressure-torsion structure 1 and the lower internal pressure-torsion structure 5 are both designed as torsional polygonal frustums, with opposite torsional directions. The two internal pressure-torsion structures are coupled in opposite directions with respect to the intermediate connecting piece 2, and are assembled and fixed by the intermediate connecting piece 2, the upper end cover 6, and the lower end cover 9; the upper internal pressure-torsion structure 1 is disposed between the upper end cover 6 and the upper surface of the intermediate connecting piece 2. The lower internal pressure-torsion structure 5 is located between the lower end cover 9 and the lower end face of the intermediate connecting piece 2; the upper external pressure-torsion structure 7 and the lower external pressure-torsion structure 8 are both designed as inclined, hollow cylindrical shapes, with opposite inclination directions. The two external pressure-torsion structures are in opposite directions about the intermediate connecting piece 2 and are assembled and fixed by the intermediate connecting piece 2, the upper end cover 6 and the lower end cover 9. The upper external pressure-torsion structure 7 is located between the upper end cover 6 and the upper end face of the intermediate connecting piece 2, and the lower external pressure-torsion structure 8 is located between the lower end cover 9 and the lower end face of the intermediate connecting piece 2. The upper end cover 6 and the lower end cover 9 are sleeved together. In this embodiment, the center of the lower end of the upper end cover 6 is provided with a rotating shaft, which is sleeved with the rotating shaft at the center of the upper end of the lower end cover 9. The intermediate connecting piece 2 is located outside the pivot of the lower end cover 9. The copper electrode layer 4 is attached to the outside of the top of the pivot of the lower end cover 9 and is in the middle of the entire shock absorber. The Ecoflex electrode layer 3 is attached to the outside of the copper electrode layer and leads out from the slit of the intermediate connecting piece 2 to the outside. The upper internal pressure-torsion structure 1 and the lower internal pressure-torsion structure 5 are embedded in the inner grooves of the intermediate connecting piece 2, the upper end cover 6, and the lower end cover 9. The upper external pressure-torsion structure 7 and the lower external pressure-torsion structure 8 are nested in the outer grooves of the intermediate connecting piece 2, the upper end cover 6, and the lower end cover 9.

[0026] In this embodiment, the upper internal pressure-torsion structure 1 and the lower internal pressure-torsion structure 5 are made by mixing Ecoflex-0050 silicone (or PDMS silicone, matrix: curing agent = 20:1) with carbonyl iron powder particles (diameter 3-5μm) with an elastic modulus of 10-100kPa at a mass ratio of 2:3 and curing them by mold. They are designed as torsion frustum shapes with a height H of 20-25mm, a top square side length l of 15-20mm, a bottom square side length L of 20-25mm, a wall thickness b of 2-5mm, and a torsion angle α of 60°-70°. Their dimensions affect the load-bearing capacity of the shock absorber and the torsion angle during the compression process. The external pressure-torsion structures 7 and 8 are fabricated using TPU or TPE filaments by an FDM 3D printer. Their diameter D is 40-45mm, height H is 20-25mm, wall thickness B is 4-7mm, and torsion angle β is 70°-80°. These dimensions affect the damper's load-bearing capacity, the torsion angle during compression, and its stability. The intermediate connecting piece 2, upper end cap 6, and lower end cap 9 are fabricated using PLA or ABS filaments by an FDM 3D printer. Their dimensions are designed for a stable fit between the upper internal pressure-torsion structure 1, lower internal pressure-torsion structure 5, upper external pressure-torsion structure 7, and lower external pressure-torsion structure 8.

[0027] In this embodiment, during vertical vibration, the internal pressure-torsion structures 1 and 5 and the external pressure-torsion structures 7 and 8 of the vibration damper 10 are subjected to pressure and torsion, driving the intermediate connecting piece to rotate in the same direction. At this time, the contact area between the Ecoflex electrode layer 3 and the copper electrode layer 4 gradually increases with the increase of the rotation angle, thereby gradually increasing its electrical signal output. Therefore, it can provide feedback on the change of torsion angle based on the magnitude of the electrical signal. Users can adjust the dimensions of the internal and external pressure-torsion structures in the vibration damper 10 according to different vibration damping requirements, thereby adjusting the performance of the vibration damper. Its dimensions can be scaled up by 1-2 times proportionally according to actual applications.

[0028] Example 2

[0029] Please see Figure 4 , Figure 5 , Figure 6 As shown, based on Embodiment 1, the present invention provides an application scheme: a magnetorheological elastomer vibration damper 10 based on a pressure-torsion coupling mechanism, wherein the vibration damper 10 is assembled with a vibration table 11 via a coupling 14, a 300g mass block 13 is placed above the vibration damper 10, an acceleration sensor 12 is placed above the mass block 13, and the outside is limited by an outer shell.

[0030] In this example, the vibration damper 10 can output a voltage signal that changes with the torsional angle. A vibration table 11 is used to simulate vibration inputs of different amplitudes. During vibration, the vibration damper 10 outputs a voltage signal, which is transmitted via wires to a computer to view the waveform of the triboelectric sensing signal. Figure 5As shown, the contact sensing signal between the Ecoflex electrode layer 3 and the copper electrode layer 4 gradually increases with the increase of amplitude; the acceleration before and after vibration reduction is measured at the vibration table 11 and the mass block 13 using the accelerometer 12, respectively. Figure 6 As shown, the vibration damping effect of damper 10 achieves a 65% attenuation rate of the root mean square value of acceleration within the 0-20Hz range. This realizes high-performance adaptive buffering across a wide frequency band.

[0031] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A magnetorheological elastic vibration damper based on a compression-torsion coupling mechanism, characterized in that, include: Upper end cap, lower end cap, middle connecting piece, upper internal pressure-torsion structure, lower internal pressure-torsion structure, upper external pressure-torsion structure, lower external pressure-torsion structure, Ecoflex electrode layer and electrode layer; The upper end cover and the lower end cover are rotatably connected; the middle connecting piece is disposed between the upper end cover and the lower end cover and can rotate relative to the upper end cover and the lower end cover; The upper internal pressure-torsion structure is connected between the upper end cover and the middle connecting piece, and the lower internal pressure-torsion structure is disposed between the lower end cover and the middle connecting piece; the upper internal pressure-torsion structure and the lower internal pressure-torsion structure have opposite torsional directions and are reverse-fitted with respect to the middle connecting piece; The upper external pressure-torsion structure is connected between the upper end cover and the middle connecting piece, and the lower external pressure-torsion structure is disposed between the lower end cover and the middle connecting piece; the upper external pressure-torsion structure and the lower external pressure-torsion structure have opposite torsional directions and are reverse-fitted with respect to the middle connecting piece; The torsional direction of the upper external pressure-torsion structure is the same as that of the upper internal pressure-torsion structure; the elastic modulus of the upper and lower external pressure-torsion structures is greater than that of the upper and lower internal pressure-torsion structures; the upper and lower internal pressure-torsion structures and the upper and lower external pressure-torsion structures are used to convert vertical vibration displacement into torsional deformation. Both the upper internal compression-torsion structure and the lower internal compression-torsion structure are magnetorheological elastic bodies, which are used to dissipate vibration energy through changes in elastic modulus and shear modulus under the action of a magnetic field. The electrode layer is disposed on the rotating part between the upper end cover and the lower end cover. The Ecoflex electrode layer is attached to the outside of the electrode layer and led out from the middle connecting piece for detecting the torsion angle.

2. The magnetorheological elastic vibration damper based on the compression-torsion coupling mechanism according to claim 1, characterized in that, The upper internal pressure-torsion structure and the lower internal pressure-torsion structure are twisted polygonal frustum shapes with a torsion angle α of 60°-70°.

3. The magnetorheological elastic vibration damper based on the compression-torsion coupling mechanism according to claim 1, characterized in that, The upper external pressure-torsion structure and the lower external pressure-torsion structure are inclined, hollow cylindrical structures with a torsion angle β of 70°-80°.

4. The magnetorheological elastic vibration damper based on the compression-torsion coupling mechanism according to claim 1, characterized in that, The upper internal pressure-torsion structure and the lower internal pressure-torsion structure are a mixture of silica gel and carbonyl iron powder particles.

5. The magnetorheological elastic vibration damper based on the compression-torsion coupling mechanism according to claim 4, characterized in that, The elastic modulus of the silicone is 10-100 kPa.

6. The magnetorheological elastic vibration damper based on the compression-torsion coupling mechanism according to claim 4, characterized in that, The silicone is either Ecoflex or PDMS silicone.

7. The magnetorheological elastic vibration damper based on the compression-torsion coupling mechanism according to claim 1, characterized in that, The upper external pressure-torsion structure and the lower external pressure-torsion structure are thermoplastic elastomers.

8. The magnetorheological elastic damper based on the compression-torsion coupling mechanism according to claim 7, characterized in that, The thermoplastic elastomer is TPU.

9. The magnetorheological elastic vibration damper based on the compression-torsion coupling mechanism according to claim 1, characterized in that, The intermediate connecting piece, upper end cap, and lower end cap are made of PLA or ABS filament by an FDM 3D printer.

10. The magnetorheological elastic damper based on the compression-torsion coupling mechanism according to claim 1, characterized in that, The device is assembled with a vibration table via a coupling, and a mass block is mounted on top of it; an acceleration sensor is mounted on top of the mass block. The vibration table is used to simulate vibration inputs of different amplitudes, and the acceleration sensor is used to test the acceleration before and after vibration reduction.

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