Phononic crystal and vibration and noise reduction fan

Abstract

The present invention discloses a phononic crystal and a vibration-reducing and noise-reducing fan, wherein the phononic crystal includes a fixedly mounted substrate and a scatterer, the substrate includes a hollow frame, at least part of the scatterer is located inside the frame, the substrate also includes a plurality of elastic beams fixedly connecting the scatterer and the frame, and the frame, the elastic beams and the scatterer form a resonant structure. The phononic crystal of the present invention forms a resonant structure through the frame, the elastic beams and the scatterer, thereby being able to effectively meet the requirements of attenuating vibration, and also has good application prospects for suppressing vibration and noise in other situations.

Description

Technical Field

[0001] The invention belongs to the field of noise reduction, and in particular relates to a phononic crystal and a vibration-reducing and noise-reducing fan. Background Art

[0002] With the development of society, noise pollution has become a problem that people have to face. Nowadays, fans are used for heat dissipation in various electronic devices. When the fan is working, the rotation of the fan blades and the vibration of the motor will generate noise. Excessive noise will seriously affect people's normal life and work. Therefore, noise control has become a problem that needs to be solved urgently.

[0003] Therefore, in view of the above technical problems, it is necessary to provide a phononic crystal and a vibration-reducing and noise-reducing fan. Summary of the invention

[0004] In view of this, an object of the present invention is to provide a phononic crystal and a vibration-reducing and noise-reducing fan to achieve vibration-reduction and noise-reduction.

[0005] In order to achieve the above purpose, the technical solution provided by an embodiment of the present invention is as follows:

[0006] A phononic crystal comprises a fixedly mounted substrate and a scatterer, wherein the substrate comprises a hollow frame, at least part of the scatterer is located inside the frame, and the substrate further comprises a plurality of elastic beams fixedly connecting the scatterer and the frame, wherein the frame, the elastic beams and the scatterer form a resonant structure.

[0007] In one embodiment, the elastic beam includes a first connecting portion vertically installed with the outer wall of the scatterer and a second connecting portion vertically installed with the inner wall of the frame. The first connecting portion and the second connecting portion are vertically installed, and the outer wall of the scatterer and the inner wall of the frame connected to the same elastic beam are vertically distributed.

[0008] In one embodiment, the scatterer includes a first scatterer mounted in cooperation with the elastic beam, and a second scatterer fixedly mounted on the first scatterer.

[0009] In one embodiment, the height of the first scatterer is greater than the height of the frame, the first scatterer is at least partially located inside the frame, and the second scatterer is at least partially located outside the frame.

[0010] In one embodiment, a cross-sectional area of ​​the first scatterer is smaller than a cross-sectional area of ​​the second scatterer.

[0011] In one embodiment, the cross-sections of the first scatterer and the second scatterer are square or rectangular.

[0012] In one embodiment, the inner cross-section of the frame is larger than the cross-section of the second scatterer.

[0013] In one embodiment, the inner cross-section of the frame is a square or a cuboid.

[0014] In one embodiment, the material of the frame includes one or more of plastic, rubber, epoxy resin and organic glass, the material of the elastic beam includes one or more of plastic, rubber, epoxy resin and organic glass, and the material of the scatterer is metal.

[0015] In one embodiment, the mass of the scatterer is greater than the mass of the matrix.

[0016] In one embodiment, the length of each side panel of the frame is 10 mm, the width is 0.5 mm, and the height is 2.5 mm; the length of the first connecting part is 1.5, the width is 1 mm, and the height is 2.5 mm, and the length of the second connecting part is 5 mm, the width is 1 mm, and the height is 2.5 mm; the side length of the first scatterer is 2.5 mm, and the height is 4 mm, and the side length of the second scatterer is 5 mm, and the height is 2 mm.

[0017] Another embodiment of the present invention provides a technical solution as follows:

[0018] A vibration-reducing and noise-reducing fan comprises a shell, a cavity in the shell, fan blades installed in the cavity, and an air inlet and an air outlet opened on the shell. A plurality of periodically arranged phononic crystals are installed on the shell at the air outlet. The plurality of array-distributed phononic crystals form a phononic crystal group. The scatterer is arranged toward the cavity in the shell.

[0019] In another embodiment, two opposite side walls of the phononic crystal group are fixed to the inner side walls of the air outlet of the shell, and the other two opposite side walls are arranged with a gap to the inner side walls of the air outlet of the shell.

[0020] In another embodiment, the first scatterer is arranged toward the outside of the cavity in the shell, and the second scatterer is arranged toward the inside of the cavity in the shell.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] The phononic crystal in the present invention forms a resonant structure through a frame, an elastic beam and a scatterer, thereby being able to effectively meet the requirement of attenuating vibrations, and also has good application prospects for suppressing vibrations and noises in other situations. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 Schematic diagram of the three-dimensional structure of a phononic crystal in one embodiment of the present invention;

[0025] Figure 2 is a top view of a phononic crystal in one embodiment of the present invention;

[0026] Figure 3 is a band gap structure diagram of a phononic crystal in one embodiment of the present invention;

[0027] Figure 4 is a transmission spectrum of a phononic crystal in one embodiment of the present invention;

[0028] Figure 5 A schematic diagram of the three-dimensional structure of a vibration-reducing and noise-reducing fan in another embodiment of the present invention;

[0029] Figure 6 FIG. 4 is a schematic diagram of the planar structure of a phononic crystal group in another embodiment of the present invention. DETAILED DESCRIPTION

[0030] The present invention will be described in detail below in conjunction with the various embodiments shown in the accompanying drawings. However, these embodiments do not limit the present invention, and any structural, methodological, or functional changes made by a person skilled in the art based on these embodiments are all within the scope of protection of the present invention.

[0031] The present invention discloses a phononic crystal and a vibration-reducing and noise-reducing fan, wherein the phononic crystal comprises a fixedly installed base and a scatterer, the base comprises a hollow frame, at least part of the scatterer is located inside the frame, the base also comprises a plurality of elastic beams fixedly connecting the scatterer and the frame, and the frame, the elastic beams and the scatterer form a resonant structure.

[0032] In addition, the vibration-damping and noise-reducing fan includes a shell, a cavity located in the shell, fan blades installed in the cavity, and an air inlet and an air outlet opened on the shell. A plurality of array-distributed phononic crystals are installed on the shell at the air outlet. The plurality of array-distributed phononic crystals form a phononic crystal group, and the scatterer is arranged toward the cavity in the shell.

[0033] The present invention is further described below in conjunction with specific embodiments.

[0034] Ginseng Figure 1As shown, a phononic crystal includes a fixedly installed substrate and a scatterer, the substrate includes a hollow frame 10, at least part of the scatterer is located inside the frame 10, the substrate also includes a plurality of elastic beams 30 fixedly connecting the scatterer and the frame 10, the frame 10, the elastic beams 30 and the scatterer form a resonant structure.

[0035] Ginseng Figure 2 As shown, the frame 10 is a rectangular column, and the inner cross-section of the frame 10 is a square. Specifically, the frame 10 is surrounded by a first side panel 11, a second side panel 12, a third side panel 13 and a fourth side panel 14 of the same size. The inner side wall of the first side panel 11, the inner side wall of the second side panel 12, the inner side wall of the third side panel 13 and the inner side wall of the fourth side panel 14 form a hollow portion, and the cross-section of the hollow portion is the inner cross-section of the frame 10, and the cross-section of the hollow portion is a square. The outer side wall of the first side panel 11, the outer side wall of the second side panel 12, the outer side wall of the third side panel 13 and the outer side wall of the fourth side panel 14 form a square outer cross-section of the frame 10.

[0036] Ginseng Figure 1 As shown, the scatterer includes a first scatterer 21 and a second scatterer 22 fixedly mounted on the first scatterer 21. The cross-sections of the first scatterer 21 and the second scatterer 22 are square or rectangular. In this embodiment, the first scatterer 21 and the second scatterer 22 are both square cylinders. The cross-sectional area of ​​the first scatterer 21 is smaller than the cross-sectional area of ​​the second scatterer 22, and the inner cross-sectional area of ​​the frame 10 is larger than the cross-sectional area of ​​the second scatterer 22.

[0037] Ginseng Figure 1 As shown, the second scatterer 22 is installed on the top of the first scatterer 21, at least part of the first scatterer 21 is located in the frame 10, and at least part of the second scatterer is located outside the frame 10. In this embodiment, part of the first scatterer 21 is located in the hollow part of the frame 10, and the entire second scatterer is located outside the frame 10. The bottom of the first scatterer 21 and the bottom of the frame 10 are located in the same plane.

[0038] Ginseng Figure 2 Combined with Figure 1 As shown, in this embodiment, four elastic beams 30 are provided, and the four elastic beams 30 are respectively distributed and installed between the inner wall of the frame 10 and the outer wall of the scatterer. The scatterer has four outer walls, and the frame 10 has four inner walls. The bottom of the elastic beam 30, the bottom of the frame 10 and the bottom of the first scatterer 21 are located in the same plane, and the top of the elastic beam 30 and the top of the frame 10 are located in the same plane.

[0039] Furthermore, each elastic beam 30 includes a first connecting portion 31 vertically installed with the outer wall of the scatterer and a second connecting portion 32 vertically installed with the inner wall of the frame 10. The first connecting portion 31 and the second connecting portion 32 are vertically installed. The outer wall of the scatterer and the inner wall of the frame 10 connected to the same elastic beam 30 are vertically distributed, and another inner wall of the frame 10 parallel to the second connecting portion 32 and closest to the second connecting portion 32 has a gap with the second connecting portion 32.

[0040] Ginseng Figure 1 As shown, the scatterer includes a first scatterer 21 installed in cooperation with the elastic beam 30 and a second scatterer 22 fixedly installed on the first scatterer 21 . The outer wall of the first scatterer 21 is installed perpendicularly to one end of the first connecting portion 31 .

[0041] Now take an elastic beam 30 as an example: the first scatterer 21 has a first outer wall and a second outer wall, the frame 10 has a first inner wall corresponding to the first outer wall and a second inner wall corresponding to the second outer wall, the first outer wall is parallel to the first inner wall, and the first outer wall is perpendicular to the second inner wall, one end of the first connecting portion 31 of the elastic beam 30 is perpendicularly installed to the first outer wall, and the other end is perpendicularly installed to one end of the second connecting portion 32, the other end of the second connecting portion 32 is perpendicularly installed to the second inner wall, the second connecting portion 32 is parallel to the first inner wall, and there is a gap between the second connecting portion 32 and the first inner wall, and the remaining three elastic beams 30 are installed in coordination with the outer wall of the first scatterer 21 and the inner wall of the frame 10 in this way.

[0042] In this embodiment, the material of the frame 10 includes one or more of plastic, rubber, epoxy resin and organic glass, and the material of the frame 10 is preferably organic glass. The material of the elastic beam 30 includes one or more of plastic, rubber, epoxy resin and organic glass, and the material of the elastic beam 30 is preferably organic glass. The density of organic glass is 1142kg / m 3 , elastic modulus is 2*10 9 pa and Poisson's ratio are 0.389.

[0043] In this embodiment, the mass of the scatterer is greater than the mass of the substrate. The material of the scatterer is metal, which includes iron, copper, aluminum, lead, steel, etc. The material of the first scatterer 21 is preferably steel, and the density of steel is 7780kg / m 3 , elastic modulus is 2.106*10 11 pa, Poisson's ratio is 0.3, the material of the second scatterer 22 is preferably lead, and the density of lead is 11600 kg / m 3 , elastic modulus is 4.082*10 10 pa and Poisson's ratio are 0.3698.

[0044] In this embodiment, the specific dimensions of each component of the phononic crystal are as follows: the first side plate 11, the second side plate 12, the third side plate 13 and the fourth side plate 14 are all vertically arranged rectangular parallelepipeds, the length of the first side plate 11, the second side plate 12, the third side plate 13 and the fourth side plate 14 are all 10 mm, the width is 0.5 mm, and the height is 2.5 mm, and the inner cross-sectional area of ​​the frame 10 is 81 mm 2 The first connecting portion 31 and the second connecting portion 32 of each elastic beam 30 are both rectangular parallelepipeds, the length of the first connecting portion 31 is 1.5, the width is 1mm, and the height is 2.5mm, and the length of the second connecting portion 32 is 5mm, the width is 1mm, and the height is 2.5mm; the first scatterer 21 and the second scatterer 22 are both square columns, the side length of the first scatterer 21 is 2.5mm, the height is 4mm, and the cross-sectional area S1 of the first scatterer 21 is 6.25mm 2 The side length of the second scatterer 22 is 5 mm, the height is 2 mm, and the cross-sectional area S2 of the second scatterer 22 is 25 mm. 2 .

[0045] Ginseng Figure 3 As shown in Figure 2, the band gap of the phononic crystal structure is calculated by the finite element method. Figure 3 The horizontal axis represents the value of the simplified wave vector K, and the vertical axis represents the frequency / Hz. Figure 3 It can be seen that the phononic crystal in this embodiment has two complete band gaps, whose ranges are 2026.8Hz-2894.4Hz and 6969.7Hz-7097.7Hz respectively. These two band gaps can meet the requirements of attenuating the vibration generated during the operation of the fan, and also have good application prospects in suppressing vibration and noise in other situations.

[0046] Ginseng Figure 4 As shown in the figure, the transmission spectrum of a finite number of units is calculated to verify the vibration reduction characteristics of the phononic crystal. Figure 4 The horizontal axis represents the frequency / Hz, and the vertical axis represents the transmission coefficient / dB. Figure 5 From the transmission spectrum, we can see that the phononic crystal has obvious attenuation in the two complete band gap ranges. In addition, due to the existence of incomplete band gaps, the phononic crystal can also suppress vibrations in other ranges.

[0047] Ginseng Figure 5As shown, the present invention also discloses a vibration-reducing and noise-reducing fan, comprising a shell 100, a cavity located in the shell 100, fan blades 200 installed in the cavity, and an air inlet 101 and an air outlet 102 opened on the shell. A plurality of array-distributed phononic crystals are installed on the shell 100 located at the air outlet 102. The plurality of array-distributed phononic crystals form a phononic crystal group 300. The scatterers are arranged toward the cavity in the shell 100. Specifically, the first scatterer 21 is arranged toward the outside of the cavity in the shell 100, and the second scatterer 22 is arranged toward the inside of the cavity in the shell 100.

[0048] Ginseng Figure 5 Combined with Figure 6 As shown, the two opposite side walls of the phononic crystal group 300 are fixed to the inner side walls of the air outlet of the shell 100, and the other two opposite side walls are set with a gap to the inner side walls of the air outlet 102 of the shell 100. The cross-section of the phononic crystal group 300 is rectangular, and the two opposite side walls of the phononic crystal group 300 include two side walls with short lengths and two side walls with long lengths. Preferably, the two opposite side walls of the phononic crystal group 300 fixed to the inner side walls of the air outlet of the shell 100 are two side walls with short lengths. By setting a gap between the side walls of the phononic crystal group 300 and the inner side walls of the air outlet 102 of the shell 100, the vibration space of the phononic crystal group 300 can be increased while increasing the air volume, thereby further improving the effect of attenuating fan noise.

[0049] It can be seen from the above technical solutions that the present invention has the following beneficial effects:

[0050] The phononic crystal in the present invention forms a resonant structure through a frame, an elastic beam and a scatterer, thereby being able to effectively meet the requirement of attenuating vibrations, and also has good application prospects for suppressing vibrations and noises in other situations.

[0051] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0052] In addition, it should be understood that although the present specification is described according to embodiments, not every embodiment contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation methods that those skilled in the art can understand.

Claims

1. A phononic crystal, characterized in that: The phononic crystal includes a fixedly mounted substrate and a scatterer, the substrate includes a hollow frame, the inner cross-section of the frame is square or rectangular, at least part of the scatterer is located inside the frame, the substrate also includes a plurality of elastic beams fixedly connecting the scatterer and the frame, the frame, the elastic beams and the scatterer form a resonant structure, the scatterer includes a first scatterer mounted in cooperation with the elastic beam, and a second scatterer fixedly mounted on the first scatterer, the cross-sections of the first scatterer and the second scatterer are square or rectangular, the elastic beam includes a first connecting portion vertically mounted to each outer side wall of the scatterer and a second connecting portion vertically mounted to each inner side wall of the frame, the first connecting portion and the second connecting portion of the elastic beam are vertically mounted, and the outer side wall of the scatterer and the inner side wall of the frame connected to the same elastic beam are vertically distributed.

2. The phononic crystal according to claim 1, characterized in that: The height of the first scatterer is greater than the height of the frame. The first scatterer is at least partially located inside the frame, and the second scatterer is at least partially located outside the frame.

3. The phononic crystal according to claim 1, characterized in that: The cross-sectional area of ​​the first scatterer is smaller than the cross-sectional area of ​​the second scatterer.

4. The phononic crystal according to claim 1, characterized in that: The inner cross-section of the frame is larger than the cross-section of the second scatterer.

5. The phononic crystal according to claim 1, characterized in that: The material of the frame includes one or more of plastic, rubber, epoxy resin and organic glass, the material of the elastic beam includes one or more of plastic, rubber, epoxy resin and organic glass, and the material of the scatterer is metal.

6. The phononic crystal according to claim 1, characterized in that: The mass of the scatterer is greater than the mass of the base.

7. The phononic crystal according to claim 1, characterized in that: The length of each side panel of the frame is 10mm, the width is 0.5mm, and the height is 2.5mm; the length of the first connecting part is 1.5, the width is 1mm, and the height is 2.5mm, and the length of the second connecting part is 5mm, the width is 1mm, and the height is 2.5mm; the side length of the first scatterer is 2.5mm and the height is 4mm, and the side length of the second scatterer is 5mm and the height is 2mm.

8. A vibration and noise reduction fan, characterized in that: The invention comprises a shell, a cavity in the shell, a fan blade installed in the cavity, and an air inlet and an air outlet opened on the shell, wherein a plurality of array-distributed phononic crystals as described in any one of claims 1 to 7 are installed on the shell at the air outlet, the plurality of array-distributed phononic crystals form a phononic crystal group, and the scatterer is arranged toward the cavity in the shell.

9. The vibration-reducing and noise-reducing fan according to claim 8, characterized in that: The two opposite side walls of the phononic crystal group are fixed to the inner side walls of the air outlet of the shell, and the other two opposite side walls are arranged with a gap between the inner side walls of the air outlet of the shell.

10. The vibration-reducing and noise-reducing fan according to claim 8, characterized in that: The first scatterer is arranged toward the outside of the cavity in the shell, and the second scatterer is arranged toward the inside of the cavity in the shell.

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