CN111457042A - Vibration isolation equipment and railway vehicle applying same - Google Patents
Vibration isolation equipment and railway vehicle applying same Download PDFInfo
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- CN111457042A CN111457042A CN202010278415.0A CN202010278415A CN111457042A CN 111457042 A CN111457042 A CN 111457042A CN 202010278415 A CN202010278415 A CN 202010278415A CN 111457042 A CN111457042 A CN 111457042A
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- outer frame
- vibration isolation
- vibration
- vehicle
- supporting
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F1/00—Springs
- F16F1/02—Springs made of steel or other material having low internal friction; Wound, torsion, leaf, cup, ring or the like springs, the material of the spring not being relevant
- F16F1/18—Leaf springs
- F16F1/26—Attachments or mountings
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F1/00—Springs
- F16F1/02—Springs made of steel or other material having low internal friction; Wound, torsion, leaf, cup, ring or the like springs, the material of the spring not being relevant
- F16F1/18—Leaf springs
- F16F1/26—Attachments or mountings
- F16F1/30—Attachments or mountings comprising intermediate pieces made of rubber or similar elastic material
Abstract
The invention relates to vibration isolation equipment and a railway vehicle applying the same, which comprise one or more vibration reduction components arranged between vehicle-mounted equipment and a vehicle body; the vibration damping component comprises a supporting and bearing part which is used for supporting the vehicle-mounted equipment and the vehicle body and bearing the vibration damping component; and an energy dissipating part for dissipating energy by resonance of response to bending waves and vertical elastic waves and internal heat dissipation. The vibration isolation device realizes the stability of the vibration isolation equipment by the supporting bearing part, and adopts the energy dissipation part to form elastic wave response resonance and internal dissipation heating in a low frequency range for energy dissipation, thereby realizing the vibration isolation effect.
Description
Technical Field
The invention relates to a vibration isolation and noise reduction device for a low frequency band, in particular to vibration isolation equipment and a railway vehicle applying the same.
Background
The rail transit has the advantages of punctuality, large passenger capacity, greenness, energy conservation, convenience and the like, and is more and more a first choice for people to go on a commute and go on a medium-distance and long-distance basis. However, the comfort of passengers is greatly influenced by low-frequency vibration and noise generated in the running process of the rail transit vehicle, the low-frequency mechanical wave and noise have strong penetrating power in the transmission process and are difficult to attenuate and cause harm to the body, the low-frequency noise and vibration mainly come from vehicle equipment excitation vibration, and the equipment installation space is extremely limited and is within 50 mm.
The traditional vibration isolator is divided into an active vibration isolator and a passive vibration isolator, and has the defects of high manufacturing cost, large size, high requirement on working environment and active energy consumption; the passive vibration isolator has poor vibration isolation effect and vibration isolation frequency which cannot meet the design requirement, and the traditional vibration isolator is utilized to realize low-frequency vibration isolation, so that the inherent frequency of the vibration isolator is required to be low, which means that the structural rigidity of the vibration isolator is low, and the vibration isolation effect of a system and the stability of the system need to be balanced. The photonic crystal metamaterial based on the local resonance principle can generate band gap characteristics, can attenuate or obstruct the transmission of mechanical waves in band gap frequency in a structure, and can control large wavelength by utilizing small size, thereby realizing low-frequency vibration isolation; on the other hand, the negative parameter characteristics such as equivalent negative stiffness or negative mass can be realized through the periodic structure design based on the negative stiffness theory, the stiffness of the system can be reduced as much as possible on the premise of keeping larger bearing capacity by combining the theory that the equivalent negative stiffness has better correspondence with the band gap, and the negative stiffness characteristics and the local resonance phonon metamaterial are effectively combined to achieve the effect of ultralow frequency vibration isolation by designing the periodic structure and the material properties.
Disclosure of Invention
The invention mainly aims to solve the technical problems in the prior art and provide vibration isolation equipment suitable for weakening low-frequency vibration.
Another main object of the present invention is to provide a rail vehicle to which the above-mentioned device is applied.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a vibration isolation apparatus includes one or more vibration damping members provided between an in-vehicle apparatus and a vehicle body;
the vibration damping component comprises a supporting and bearing part which is used for supporting the vehicle-mounted equipment and the vehicle body and bearing the vibration damping component;
and an energy dissipating part for dissipating energy by resonance of response to bending waves and vertical elastic waves and internal heat dissipation.
Based on the technical scheme, the vibration isolation equipment realizes the stability of the vibration isolation equipment through the supporting bearing part, and the energy dissipation part is adopted to form elastic wave response resonance and internal dissipation heating in a low frequency range for energy dissipation, so that the vibration isolation effect is realized.
Further, the damping member includes one or more unit cells, each of which includes the support bearing portion and the energy dissipating portion.
Based on the technical scheme, the multiple unit cells can form the vibration isolation component with practical application functions by combining multiple unit cells with equivalent negative stiffness characteristics at low frequency so as to adapt to different installation positions and facilitate the use in small-size installation space.
Further, the supporting and bearing part comprises a vertical beam, the energy dissipation part comprises a cross beam and an oblique beam, and the unit cell is of a structure in a shape like a Chinese character 'mi' and is composed of the vertical beam, the cross beam and the oblique beam.
The unit cell adopts a structure in a shape of Chinese character mi, a finite entity structure of the unit cell has loss peak values near a plurality of frequencies in excitation-response analysis, the vibration isolation effect is good, and the rigidity of the unit cell structure is reduced on the premise of keeping the bearing capacity as much as possible.
Furthermore, the supporting and bearing part adopts a metal material/high molecular polymer with low density and high hardness; the energy dissipation part is made of nitrile rubber, silicon rubber or composite rubber material flexible material.
Furthermore, the unit cell length is 25mm, the width is 20mm, the height is 25mm, the thickness of vertical beam, crossbeam and sloping is 2mm, the angle of sloping and crossbeam is 45 degrees.
Based on the technical scheme, the negative stiffness theory and the local resonance metamaterial theory are combined, and the material property, the thickness of the cross beam, the angle between the oblique beam and the cross beam and the thickness of the oblique beam of the vibration isolation structure are set, so that the vibration isolation structure has equivalent negative stiffness characteristics at low frequency, and a Mi-shaped unit cell structure with equivalent negative stiffness characteristics and a vibration damping part consisting of unit cells are formed.
Further, an upper outer frame is arranged between the vibration damping component and the vehicle-mounted equipment, the upper outer frame is sleeved on the vibration damping component, and an outer frame-equipment connecting bolt structure used for being fixed with the vehicle-mounted equipment and a metamaterial-outer frame connecting bolt structure used for being fixed with the supporting bearing portion are arranged on the upper outer frame.
Further, a lower outer frame is arranged between the vibration damping component and the vehicle body, the lower outer frame is sleeved on the vibration damping component, and an outer frame-vehicle body connecting bolt structure for fixing with the vehicle body and a metamaterial-outer frame connecting bolt structure for fixing with the supporting bearing part are arranged on the lower outer frame.
The upper and lower outer frame structures limit the maximum transverse and vertical displacement of the vibration reduction component on one hand, improve the impact resistance of the vibration reduction component and simultaneously play a role in connecting the internal vibration reduction component with the vehicle-mounted equipment and the vehicle body.
Further, the upper outer frame and the lower outer frame are fixedly connected through an upper-lower outer frame connecting bolt structure.
The upper outer frame and the lower outer frame are fixed into a whole, so that the stability of the inner vibration reduction component and the whole outer frame is improved.
Further, a rubber buffer gasket is arranged between the upper outer frame and the lower outer frame.
The rubber buffer gasket can adjust size and material parameters according to actual requirements, has the function of preventing the contact damage of the upper and lower outer frames, and can buffer and reduce vibration.
The other technical scheme of the invention is as follows:
a rail vehicle comprises a vehicle body and various vehicle-mounted devices, wherein the vibration isolation device is arranged between the vehicle-mounted devices and the vehicle body.
In summary, the vibration isolation device and the rail vehicle using the same provided by the invention have the following advantages:
1. the vibration reduction component is set to have negative rigidity, a forbidden band which can not be passed by elastic waves is formed in an ultralow frequency range, and the upper outer frame and the lower outer frame are arranged outside the vibration reduction component, so that the vibration reduction component with the internal square-shaped negative rigidity is connected with a vehicle body and vibration source equipment, a structure with practical application functions is formed, an effective low-frequency vibration reduction function is achieved, and vehicle equipment can be borne.
2. Under the small-size installation space, effectively realize being less than the good vibration isolation sound insulation effect of the low frequency vibration noise of 100Hz to on-vehicle equipment, increase equipment life, improve the environment of taking.
3. The finite entity structure of the Mi-shaped unit cell structure has loss amount peak values near a plurality of frequencies in excitation-response analysis and has a good vibration isolation effect.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic vertical cross-section of the present invention;
fig. 3 is a schematic diagram of the structure of a unit cell of the present invention;
FIG. 4 is a schematic structural view of the vibration damping member of the present invention;
FIG. 5 is a bandgap diagram of a single cell of the present invention;
fig. 6 is a graph showing the transmission loss of the damping member of the present invention.
As shown in fig. 1 to 6, a vibration damping member 1, a vertical beam 1-1, a cross beam 1-2, an oblique beam 1-3, an upper outer frame 2, a lower outer frame 3, an outer frame-device connecting bolt structure 4, a metamaterial-outer frame connecting bolt structure 5, an outer frame-vehicle body connecting bolt structure 6, an upper-lower outer frame connecting bolt structure 7, and a rubber cushion 8.
Detailed Description
The invention is described in further detail below with reference to the following detailed description and accompanying drawings:
in order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
As shown in fig. 1 and 2, a vibration isolation device includes one or more vibration damping members 1 disposed between an in-vehicle device and a vehicle body, and an upper outer frame 2 and a lower outer frame 3 are disposed outside the vibration damping members 1. According to the invention, the vibration damping component 1 is set to have negative stiffness characteristic, a forbidden band which can not be passed by elastic waves is formed in an ultralow frequency range, and the upper outer frame and the lower outer frame are arranged outside the vibration damping component 1, so that the vibration damping component 1 with the internal square negative stiffness characteristic is connected with the vehicle body and vibration source equipment, a structure with practical application functions is formed, an effective low-frequency vibration damping function is achieved, and vehicle equipment can be borne. Experiments prove that the vibration isolation and sound insulation device can effectively realize good vibration isolation and sound insulation effects on low-frequency vibration noise of vehicle-mounted equipment lower than 100Hz in a small-size installation space, prolongs the service life of the equipment and improves the riding environment.
The vibration damping member 1 includes a support bearing portion for supporting the in-vehicle device and the vehicle body and bearing the vibration damping member. And an energy dissipating part for dissipating energy by resonance of response to bending waves and vertical elastic waves and internal heat dissipation. The vibration isolation equipment realizes the stability of the vibration isolation equipment by supporting the bearing part, and the energy dissipation part is adopted to dissipate energy by forming elastic wave response resonance and internal dissipation heating in a low frequency range, so that the vibration isolation effect is realized.
As shown in fig. 3 and 4, the damping member 1 includes one or more cells, each of which includes the supporting and bearing portion and the energy dissipating portion, and in this embodiment, the damping member 1 is formed by a 2 × 2 cell arrangement. The unit cell is designed to have negative rigidity characteristic, and the multiple unit cells can form a plurality of unit cells with equivalent negative rigidity characteristic at low frequency into the vibration isolation component 1 with practical application function by various combination modes so as to adapt to different installation positions and facilitate the use under small-size installation space.
In this embodiment, the supporting and carrying portion of the cell includes a vertical beam 1-1, the energy dissipation portion includes a beam 1-2 and an oblique beam 1-3, and the cell is a cross-shaped structure composed of the vertical beam 1-1, the beam 1-2 and the oblique beam 1-3. As shown in fig. 5, the unit cell has a structure in a shape of a Chinese character mi, and its finite entity structure has loss peaks near a plurality of frequencies in the excitation-response analysis and has a good vibration isolation effect, and the rigidity of the unit cell structure is reduced on the premise of maintaining the bearing capacity as much as possible.
Specifically, the upper outer frame 2, the lower outer frame 3, and the vertical beams 1-1 are made of a low-density high-hardness metal material/high-molecular polymer. The cross beams 1-2 and the oblique beams 1-3 are made of nitrile rubber, silicon rubber or composite rubber flexible materials. The unit cell length is 25mm, the width is 20mm, the height is 25mm, the thicknesses of the vertical beam 1-1, the cross beam 1-2 and the oblique beam 1-3 are 2mm, and the angle between the oblique beam 1-3 and the cross beam 1-2 is 45 degrees. By combining the negative stiffness theory and the local resonance metamaterial theory, the material property of the vibration isolation structure 1, the thickness of the cross beam 1-2, the angle between the oblique beam 1-3 and the cross beam 1-2 and the thickness of the oblique beam 1-3 are set, so that the vibration isolation structure has equivalent negative stiffness characteristics at low frequency, and a Mi-shaped unit cell structure with equivalent negative stiffness characteristics and a vibration attenuation part 1 consisting of unit cells are formed. As shown in FIG. 6, the dispersion curve of the infinite periodic structure is calculated by applying periodic boundary conditions at the cell boundary, and it is found that a vertical elastic wave band gap is generated at 32-38Hz, i.e. the vertical elastic wave is greatly attenuated or even cannot pass through in the frequency range. And (3) performing excitation response calculation on the vibration reduction component 1 consisting of 2 x 2 unit cells to obtain a result consistent with the dispersion analysis result. By changing the thickness of the beam, the angle of the cross beam 1-2 and the oblique beam 1-3, and the properties of the material, the vibration can be isolated in a targeted manner.
The upper outer frame 2 is arranged between the vibration damping component 1 and the vehicle-mounted equipment, the upper outer frame 2 is sleeved on the vibration damping component 1, an outer frame-equipment connecting bolt structure 4 for fixing with the vehicle-mounted equipment and a metamaterial-outer frame connecting bolt structure 5 for fixing with the supporting bearing part are arranged on the upper outer frame 2, and the vertical beam 1-1 and the upper outer frame 2 are fixed through the metamaterial-outer frame connecting bolt structure 5.
The lower outer frame 3 is arranged between the vibration damping part 1 and the vehicle body, the lower outer frame 3 is sleeved on the vibration damping part 1, and an outer frame-vehicle body connecting bolt structure 6 for fixing with the vehicle body and a metamaterial-outer frame connecting bolt structure 5 for fixing with the supporting bearing part are arranged on the lower outer frame 3, namely the metamaterial-outer frame connecting bolt structure 5 is used for fixing the vertical beam 1-1 and the lower outer frame 3.
The upper and lower outer frame structures are arranged to limit the maximum transverse and vertical displacement of the vibration damping component 1, improve the impact resistance of the vibration damping component 1 and simultaneously undertake the function of connecting the internal vibration damping component 1 with the vehicle-mounted equipment and the vehicle body. The upper and lower outer frames are fixed with the vertical beam 1-1, so that the structure is more stable.
In this embodiment, the vibration damping member 1 is externally fitted with vibration damping devices in which upper and lower outer frames are fixed to form a whole, the upper and lower outer frame plates have a length of 52mm, a width of 21mm, a height of 23mm, and a thickness of 1.5mm, and the whole size is small, so that the vibration damping member is suitable for a small-sized installation space.
The upper outer frame 2 and the lower outer frame 3 are fixedly connected by an upper-lower outer frame connecting bolt structure 7. By fixing the upper and lower outer frames as a whole, the stability of the inner damping member 1 and the outer frame as a whole is improved.
A rubber cushion 8 is provided between the upper outer frame 2 and the lower outer frame 3. The rubber buffer gasket 8 can adjust the size and material parameters according to actual requirements, has the function of preventing the contact damage of the upper and lower outer frames, and can buffer and damp vibration.
The bolts used by all the connecting bolts are high-strength bolts and are provided with flat elastic gaskets or butterfly gaskets.
A rail vehicle comprises a vehicle body and various vehicle-mounted devices, wherein the vibration isolation device is arranged between the vehicle-mounted devices and the vehicle body.
Similar solutions can be derived from the solution given in the figures, as described above. However, any simple modification, equivalent change and modification of the above embodiments according to the technical essence of the present invention are within the scope of the technical solution of the present invention.
Claims (10)
1. A vibration isolation apparatus, characterized in that: one or more vibration damping members provided between the in-vehicle apparatus and the vehicle body;
the vibration damping component comprises a supporting and bearing part which is used for supporting the vehicle-mounted equipment and the vehicle body and bearing the vibration damping component;
and an energy dissipating part for dissipating energy by resonance of response to bending waves and vertical elastic waves and internal heat dissipation.
2. The vibration isolation apparatus according to claim 1, wherein: the damping component comprises one or more unit cells, and each unit cell comprises the supporting bearing part and the energy dissipation part.
3. The vibration isolation apparatus according to claim 2, wherein: the supporting and bearing part comprises a vertical beam, the energy dissipation part comprises a cross beam and an oblique beam, and the unit cell is of a structure shaped like a Chinese character 'mi' and consists of the vertical beam, the cross beam and the oblique beam.
4. A vibration isolation apparatus as claimed in claim 3, wherein: the supporting and bearing part is made of low-density high-hardness metal material/high molecular polymer; the energy dissipation part is made of nitrile rubber, silicon rubber or composite rubber material flexible material.
5. The vibration isolation apparatus according to claim 4, wherein: the unit cell length is 25mm, the width is 20mm, the height is 25mm, the thickness of vertical beam, crossbeam and sloping is 2mm, the angle of sloping and crossbeam is 45 degrees.
6. The vibration isolation apparatus according to claim 1, wherein: an upper outer frame is arranged between the vibration damping component and the vehicle-mounted equipment, the upper outer frame is sleeved on the vibration damping component, and an outer frame-equipment connecting bolt structure used for being fixed with the vehicle-mounted equipment and a metamaterial-outer frame connecting bolt structure used for being fixed with the supporting bearing part are arranged on the upper outer frame.
7. The vibration isolation apparatus according to claim 6, wherein: the vibration damping device is characterized in that a lower outer frame is arranged between the vibration damping component and the vehicle body, the lower outer frame is sleeved on the vibration damping component, and an outer frame-vehicle body connecting bolt structure for being fixed with the vehicle body and a metamaterial-outer frame connecting bolt structure for being fixed with the supporting bearing part are arranged on the lower outer frame.
8. The vibration isolation apparatus according to claim 7, wherein: the upper outer frame and the lower outer frame are fixedly connected through an upper-lower outer frame connecting bolt structure.
9. The vibration isolation apparatus according to claim 7, wherein: and a rubber buffer gasket is arranged between the upper outer frame and the lower outer frame.
10. The utility model provides a rail vehicle, includes automobile body and all kinds of mobile unit, its characterized in that: a vibration isolation device according to any one of claims 1 to 9 is provided between the vehicle-mounted device and a vehicle body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010278415.0A CN111457042B (en) | 2020-04-10 | 2020-04-10 | Vibration isolation equipment and railway vehicle applying same |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010278415.0A CN111457042B (en) | 2020-04-10 | 2020-04-10 | Vibration isolation equipment and railway vehicle applying same |
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| CN111457042A true CN111457042A (en) | 2020-07-28 |
| CN111457042B CN111457042B (en) | 2021-08-27 |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1958889A2 (en) * | 2007-02-16 | 2008-08-20 | Giorgio De Riso | Structure for dissipating impact energy |
| CN107542823A (en) * | 2017-07-19 | 2018-01-05 | 华南农业大学 | A kind of pressure buffer structure |
| CN108361314A (en) * | 2018-01-29 | 2018-08-03 | 南京依维柯汽车有限公司 | A kind of air spring low frequency vibration isolation device folded based on three Pus |
| CN110645298A (en) * | 2019-09-17 | 2020-01-03 | 吉林大学 | Double-platform filling structure with double protection |
-
2020
- 2020-04-10 CN CN202010278415.0A patent/CN111457042B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1958889A2 (en) * | 2007-02-16 | 2008-08-20 | Giorgio De Riso | Structure for dissipating impact energy |
| CN107542823A (en) * | 2017-07-19 | 2018-01-05 | 华南农业大学 | A kind of pressure buffer structure |
| CN108361314A (en) * | 2018-01-29 | 2018-08-03 | 南京依维柯汽车有限公司 | A kind of air spring low frequency vibration isolation device folded based on three Pus |
| CN110645298A (en) * | 2019-09-17 | 2020-01-03 | 吉林大学 | Double-platform filling structure with double protection |
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| CN111457042B (en) | 2021-08-27 |
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