阅读说明：本技术 一种基于声学超材料的3d打印机噪声抑制结构 (3D printer noise suppression structure based on acoustics metamaterial ) 是由 杨天 杨天智 王晓宇 于 2021-08-06 设计创作，主要内容包括：一种基于声学超材料的3D打印机噪声抑制结构,包括下底板、左挡板、后挡板、上框架及前、右、上降噪管组；上框架水平设在下底板正上方；左挡板竖直设在上框架的左边框与下底板之间；后挡板竖直设在上框架的后边框与下底板之间；前降噪管组竖直设在上框架的前边框与下底板之间；右降噪管组竖直设在上框架的右边框与下底板之间；上降噪管组水平设在上框架的前边框与后边框之间；后挡板的中部设有排尘风扇；所有降噪管结构相同且均采用同轴嵌套式双管结构,包括降噪内管和降噪外管,降噪内管和降噪外管的截面形状均为C形。本发明利用亥姆霍兹共振原理,仅通过结构自身几何特征即可实现对特定频段噪声的抑制,可实现降噪、冷却和排尘的功能结合。(A3D printer noise suppression structure based on an acoustic metamaterial comprises a lower bottom plate, a left baffle, a rear baffle, an upper frame, a front noise reduction pipe group, a right noise reduction pipe group and an upper noise reduction pipe group; the upper frame is horizontally arranged right above the lower bottom plate; the left baffle is vertically arranged between the left frame of the upper frame and the lower bottom plate; the rear baffle is vertically arranged between the rear frame of the upper frame and the lower bottom plate; the front noise reduction pipe group is vertically arranged between the front frame and the lower bottom plate of the upper frame; the right noise reduction pipe group is vertically arranged between the right frame and the lower bottom plate of the upper frame; the upper noise reduction pipe group is horizontally arranged between the front frame and the rear frame of the upper frame; the middle part of the rear baffle is provided with a dust exhaust fan; all the noise reduction pipe structures are the same and adopt coaxial nested double-pipe structures, including the noise reduction inner pipe and the noise reduction outer pipe, the cross-sectional shapes of the noise reduction inner pipe and the noise reduction outer pipe are both C-shaped. According to the invention, the Helmholtz resonance principle is utilized, the noise suppression of a specific frequency band can be realized only through the self geometric characteristics of the structure, and the combination of the functions of noise reduction, cooling and dust exhaust can be realized.)

1. The utility model provides a 3D printer noise suppression structure based on super material of acoustics which characterized in that: the device comprises a lower bottom plate, a left baffle, a rear baffle, an upper frame, a front noise reduction pipe group, a right noise reduction pipe group and an upper noise reduction pipe group; the lower bottom plate is horizontally arranged, and the upper frame is horizontally arranged right above the lower bottom plate; the left baffle is vertically arranged between the left frame of the upper frame and the lower bottom plate; the rear baffle is vertically arranged between the rear frame of the upper frame and the lower bottom plate; the front noise reduction pipe group is vertically arranged between the front frame and the lower bottom plate of the upper frame; the right noise reduction pipe group is vertically arranged between the right frame and the lower bottom plate of the upper frame; the upper noise reduction pipe group is horizontally arranged between the front frame and the rear frame of the upper frame; a dust exhaust fan is arranged in the middle of the rear baffle; the pipe group of making an uproar falls in the preceding, the right side fall and fall the pipe group of making an uproar and go up and fall the interior noise reduction tube structure of the pipe group of making an uproar and the same, all adopt coaxial nested formula double-barrelled structure, including falling the inner tube of making an uproar and falling the outer tube of making an uproar, and fall the inner tube of making an uproar and fall the cross sectional shape of the outer tube of making an uproar and be C shape.

2. The acoustic metamaterial-based 3D printer noise suppression structure as claimed in claim 1, wherein: in the front noise reduction pipe group, the right noise reduction pipe group and the upper noise reduction pipe group, the inner radius of the section of the noise reduction inner pipe is recorded as r₁And the outer radius of the cross section of the noise reduction inner pipe is recorded as r₂The inner radius of the cross section of the noise reduction outer pipe is recorded as R₁And the outer radius of the cross section of the noise reduction outer tube is recorded as R₂The utility model discloses a 3D printer, the opening width of making an uproar inner tube and making an uproar outer tube is equal and mark as K, the opening contained angle of making an uproar inner tube and making an uproar outer tube is 180, and the opening orientation 3D printer of making an uproar outer tube of making an uproar falls.

3. The acoustic metamaterial-based 3D printer noise suppression structure as claimed in claim 2, wherein: in the front noise reduction pipe group, the right noise reduction pipe group and the upper noise reduction pipe group, the height of each noise reduction pipe is recorded as H, the distance between every two adjacent noise reduction pipes is recorded as L, and the outer radius of the cross section of each noise reduction outer pipe is recorded as R₂And L is 2R₂(ii) a The height H of the noise reduction pipe is 50 mm-500 mm.

4. The acoustic metamaterial-based 3D printer noise suppression structure as claimed in claim 3, wherein: when noise is generatedWhen the central frequency is 1300 Hz-1400 Hz, the inner radius r of the cross section of the noise reduction inner pipe₁Is 5mm, and the outer radius r of the cross section of the noise reduction inner pipe₂8.5 mm-9.5 mm, and the inner radius R of the cross section of the noise reduction outer pipe₁12 mm-14 mm, and the outer radius R of the cross section of the noise reduction outer tube₂19mm, and the opening width K of the noise reduction inner tube and the noise reduction outer tube is 4.5 mm.

5. The acoustic metamaterial-based 3D printer noise suppression structure as claimed in claim 3, wherein: when the noise center frequency is 1400 Hz-1500 Hz, the inner radius r of the cross section of the noise reduction inner pipe₁Is 5mm, and the outer radius r of the cross section of the noise reduction inner pipe₂7.5 mm-8.5 mm, and the inner radius R of the cross section of the noise reduction outer tube₁Is 11 mm-12 mm, and the outer radius R of the cross section of the noise reduction outer tube₂Is 19mm, and the opening width K of the noise reduction inner tube and the noise reduction outer tube is 5 mm.

6. The acoustic metamaterial-based 3D printer noise suppression structure as claimed in claim 3, wherein: when the noise center frequency is 1500 Hz-1600 Hz, the inner radius r of the cross section of the noise reduction inner pipe₁Is 5mm, and the outer radius r of the cross section of the noise reduction inner pipe₂6.5 mm-7.5 mm, and the inner radius R of the cross section of the noise reduction outer tube₁10 mm-11 mm, and the outer radius R of the cross section of the noise reduction outer tube₂19mm, and the opening width K of the noise reduction inner tube and the noise reduction outer tube is 5.5 mm.

7. The acoustic metamaterial-based 3D printer noise suppression structure as claimed in claim 3, wherein: when the noise center frequency is 1600 Hz-1700 Hz, the inner radius r of the cross section of the noise reduction inner pipe₁Is 5mm, and the outer radius r of the cross section of the noise reduction inner pipe₂6 mm-6.5 mm, and the inner radius R of the cross section of the noise reduction outer tube₁9 mm-10 mm, and the outer radius R of the cross section of the noise reduction outer tube₂Is 19mm, and the opening width K of the noise reduction inner tube and the noise reduction outer tube is 6 mm.

8. The acoustic metamaterial-based 3D printer noise suppression structure as claimed in claim 1, wherein: when the rotation angle of the noise reduction inner tube relative to the noise reduction outer tube is adjustable, the opening included angle of the noise reduction inner tube and the noise reduction outer tube is adjusted by adjusting the rotation angle of the noise reduction inner tube so as to change the noise center frequency which can be restrained by the noise reduction tube.

9. The acoustic metamaterial-based 3D printer noise suppression structure as claimed in claim 8, wherein: when the cross section inner radius r of the noise reduction inner pipe₁Is 5mm, and the section outer radius r of the noise reduction inner pipe₂8.5mm, and the inner radius R of the cross section of the noise reduction outer tube₁Is 12mm, and the section outer radius R of the noise reduction outer tube₂19mm, and the opening width K of the noise reduction inner pipe and the noise reduction outer pipe is 4.5mm, the opening included angle of the noise reduction inner pipe and the noise reduction outer pipe is changed between 180 degrees and 0 degrees, and then the center frequency of noise which can be inhibited by the noise reduction pipe is changed between 1386Hz and 1616 Hz.

10. The acoustic metamaterial-based 3D printer noise suppression structure as claimed in claim 1, wherein: the lower bottom plate, the left baffle and the rear baffle are all made of acrylic plates; the upper frame is made of aluminum alloy; the noise reduction inner pipe and the noise reduction outer pipe are made of resin.

Technical Field

The invention belongs to the technical field of noise reduction, and particularly relates to a 3D printer noise suppression structure based on an acoustic metamaterial.

Background

At present, the 3D printing technology has been widely applied to the fields of manufacturing, medical treatment, building, aerospace and the like, but with the normal background of the application of the 3D printing technology in the laboratory environment and even the household use of daily life, the problem of exposed pollution hazards is also more serious.

On the one hand, 3D printers are operated to continuously release toxic particles that are hazardous to human health, and these numerous Ultra Fine Particles (UFPs) present in the environment are typically no more than 100 nm in diameter, which are small enough to be deposited in the lungs or directly absorbed by the blood if inhaled by the human body, thus posing a health hazard.

On the other hand, the 3D printer may continuously generate low-frequency weak noise during operation, the continuous low-frequency weak noise is often easily overlooked pollution, and the continuous low-frequency weak noise may have adverse effects on the nervous system, endocrine system and cardiovascular system of people.

For this reason, the dust and noise pollution problem of 3D printers is gradually emphasized, but the emphasis is far from enough, and most of the 3D printers still operate in a bare state, so the health hazard is still continuous.

When solving the 3D printer noise pollution problem, the existing noise reduction and sound absorption structure mostly utilizes viscous friction and heat conduction effect of noise when the noise is transmitted in the material to absorb the noise, so the noise reduction effect is poor, and the existing noise reduction and sound absorption structure generally adopts a closed cavity structure, the closed cavity design easily causes the overheating of the temperature in the cavity, so the ventilation and cooling can be carried out only through forced convection, but the space occupancy of the forced convection ventilation and cooling system is higher, and the energy consumption is also higher.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a noise suppression structure of a 3D printer based on an acoustic metamaterial, which can realize the suppression of noise of a specific frequency band only through the self geometric characteristics of the structure by utilizing the Helmholtz resonance principle, can realize the heat dissipation only through natural convection by adopting an open cavity design, and simultaneously realizes the function combination of noise reduction, cooling and dust exhaust, and has the characteristics of simple structure, safety, reliability, energy conservation and environmental protection.

In order to achieve the purpose, the invention adopts the following technical scheme: A3D printer noise suppression structure based on acoustic metamaterials comprises a lower bottom plate, a left baffle, a rear baffle, an upper frame, a front noise reduction pipe group, a right noise reduction pipe group and an upper noise reduction pipe group; the lower bottom plate is horizontally arranged, and the upper frame is horizontally arranged right above the lower bottom plate; the left baffle is vertically arranged between the left frame of the upper frame and the lower bottom plate; the rear baffle is vertically arranged between the rear frame of the upper frame and the lower bottom plate; the front noise reduction pipe group is vertically arranged between the front frame and the lower bottom plate of the upper frame; the right noise reduction pipe group is vertically arranged between the right frame and the lower bottom plate of the upper frame; the upper noise reduction pipe group is horizontally arranged between the front frame and the rear frame of the upper frame; a dust exhaust fan is arranged in the middle of the rear baffle; the pipe group of making an uproar falls in the preceding, the right side fall and fall the pipe group of making an uproar and go up and fall the interior noise reduction tube structure of the pipe group of making an uproar and the same, all adopt coaxial nested formula double-barrelled structure, including falling the inner tube of making an uproar and falling the outer tube of making an uproar, and fall the inner tube of making an uproar and fall the cross sectional shape of the outer tube of making an uproar and be C shape.

In the front noise reduction pipe group, the right noise reduction pipe group and the upper noise reduction pipe group, the inner radius of the section of the noise reduction inner pipe is recorded as r₁And the outer radius of the cross section of the noise reduction inner pipe is recorded as r₂The inner radius of the cross section of the noise reduction outer pipe is recorded as R₁And the outer radius of the cross section of the noise reduction outer tube is recorded as R₂The utility model discloses a 3D printer, the opening width of making an uproar inner tube and making an uproar outer tube is equal and mark as K, the opening contained angle of making an uproar inner tube and making an uproar outer tube is 180, and the opening orientation 3D printer of making an uproar outer tube of making an uproar falls.

In the front noise reduction pipe group, the right noise reduction pipe group and the upper noise reduction pipe group, the height of each noise reduction pipe is recorded as H, the distance between every two adjacent noise reduction pipes is recorded as L, and the outer radius of the cross section of each noise reduction outer pipe is recorded as R₂And L is 2R₂(ii) a The height H of the noise reduction pipe is 50 mm-500 mm.

When the central frequency of the noise is 1300 Hz-1400 Hz, the inner radius r of the cross section of the noise reduction inner pipe₁Is 5mm, and the outer radius r of the cross section of the noise reduction inner pipe₂8.5 mm-9.5 mm, and the inner radius R of the cross section of the noise reduction outer pipe₁12 mm-14 mm, and the outer radius R of the cross section of the noise reduction outer tube₂19mm, and the opening width K of the noise reduction inner tube and the noise reduction outer tube is 4.5 mm.

When the noise center frequency is 1400 Hz-1500 Hz, the inner radius r of the cross section of the noise reduction inner pipe₁Is 5mm, and the outer radius r of the cross section of the noise reduction inner pipe₂7.5 mm-8.5 mm, and the inner radius R of the cross section of the noise reduction outer tube₁Is 11 mm-12 mm, and the outer radius R of the cross section of the noise reduction outer tube₂Is 19mm, and the opening width K of the noise reduction inner tube and the noise reduction outer tube is 5 mm.

When the noise center frequency is 1500 Hz-1600 Hz, the inner radius r of the cross section of the noise reduction inner pipe₁Is 5mm, and the outer radius r of the cross section of the noise reduction inner pipe₂6.5 mm-7.5 mm, and the inner radius R of the cross section of the noise reduction outer tube₁10 mm-11 mm, and the outer radius R of the cross section of the noise reduction outer tube₂19mm, and the opening width K of the noise reduction inner tube and the noise reduction outer tube is 5.5 mm.

When the noise center frequency is 1600 Hz-1700 Hz, the inner radius r of the cross section of the noise reduction inner pipe₁Is 5mm, and the outer radius r of the cross section of the noise reduction inner pipe₂6 mm-6.5 mm, and the inner radius R of the cross section of the noise reduction outer tube₁9 mm-10 mm, and the outer radius R of the cross section of the noise reduction outer tube₂Is 19mm, and the opening width K of the noise reduction inner tube and the noise reduction outer tube is 6 mm.

When the rotation angle of the noise reduction inner tube relative to the noise reduction outer tube is adjustable, the opening included angle of the noise reduction inner tube and the noise reduction outer tube is adjusted by adjusting the rotation angle of the noise reduction inner tube so as to change the noise center frequency which can be restrained by the noise reduction tube.

When the cross section inner radius r of the noise reduction inner pipe₁Is 5mm, and the section outer radius r of the noise reduction inner pipe₂8.5mm, and the inner radius R of the cross section of the noise reduction outer tube₁Is 12mm, and the section outer radius R of the noise reduction outer tube₂Is 19mm, and the opening widths K of the noise reduction inner tube and the noise reduction outer tube are 4.5mmThe opening included angle between the noise reduction outer pipe and the noise reduction inner pipe is changed between 180 degrees and 0 degrees, and then the center frequency of noise which can be suppressed by the noise reduction outer pipe is changed between 1386Hz and 1616 Hz.

The lower bottom plate, the left baffle and the rear baffle are all made of acrylic plates; the upper frame is made of aluminum alloy; the noise reduction inner pipe and the noise reduction outer pipe are made of resin.

The invention has the beneficial effects that:

according to the 3D printer noise suppression structure based on the acoustic metamaterial, the Helmholtz resonance principle is utilized, the suppression of noise of a specific frequency band can be realized only through the self geometric characteristics of the structure, the heat dissipation can be realized only through natural convection by adopting an open cavity design, the combination of the functions of noise reduction, cooling and dust exhaust is realized, and the 3D printer noise suppression structure based on the acoustic metamaterial has the characteristics of simple structure, safety, reliability, energy conservation and environmental friendliness.

Drawings

FIG. 1 is a schematic diagram of a noise suppression structure of a 3D printer based on an acoustic metamaterial according to the present invention;

FIG. 2 is a schematic cross-sectional view of a noise reduction tube of the present invention;

FIG. 3 is a diagram showing the noise reduction effect of a noise reduction tube (the included angle between the openings of the inner noise reduction tube and the outer noise reduction tube is 180 °) when the center frequency of noise is 1386 Hz;

FIG. 4 is a diagram showing the noise reduction effect of the front/right/upper noise reduction tube set (the opening angle between the noise reduction inner tube and the noise reduction outer tube is 180 °) when the center frequency of noise is 1386 Hz;

FIG. 5 is a diagram of the noise suppression spectrum of the front/right/upper noise reduction tube set (the opening angle between the noise reduction inner tube and the noise reduction outer tube is 180 °) at a noise center frequency of 1386 Hz;

FIG. 6 is a diagram showing the noise reduction effect of the front/right/upper noise reduction tube set (the opening angle between the noise reduction inner tube and the noise reduction outer tube is 120 °) when the noise center frequency is 1394 Hz;

FIG. 7 is a diagram showing a noise suppression spectrum of the front/right/upper noise reduction tube set (the opening angle between the noise reduction inner tube and the noise reduction outer tube is 120 °) when the center frequency of noise is 1394 Hz;

FIG. 8 is a diagram showing the noise reduction effect of the front/right/upper noise reduction tube set (the opening angle between the noise reduction inner tube and the noise reduction outer tube is 90 °) at a noise center frequency of 1457 Hz;

FIG. 9 is a diagram of noise suppression spectrum of the front/right/upper noise reduction tube set (the opening angle between the inner noise reduction tube and the outer noise reduction tube is 90 °) at a noise center frequency of 1457 Hz;

FIG. 10 is a diagram showing the noise reduction effect of the front/right/upper noise reduction tube set (the opening angle between the noise reduction inner tube and the noise reduction outer tube is 30 °) when the noise center frequency is 1587 Hz;

FIG. 11 is a diagram of a noise suppression spectrum of a front/right/upper noise reduction tube set (an opening angle between a noise reduction inner tube and a noise reduction outer tube is 30 °) when a noise center frequency is 1587 Hz;

in the figure, 1-lower base plate, 2-left baffle, 3-rear baffle, 4-upper frame, 5-front noise reduction pipe group, 6-right noise reduction pipe group, 7-upper noise reduction pipe group and 8-dust exhaust fan.

Detailed Description

The invention is described in further detail below with reference to the figures and the specific embodiments.

As shown in fig. 1 to 11, a 3D printer noise suppression structure based on an acoustic metamaterial includes a lower base plate 1, a left baffle 2, a rear baffle 3, an upper frame 4, a front noise reduction tube group 5, a right noise reduction tube group 6, and an upper noise reduction tube group 7; the lower bottom plate 1 is horizontally arranged, and the upper frame 4 is horizontally arranged right above the lower bottom plate 1; the left baffle 2 is vertically arranged between the left frame of the upper frame 4 and the lower bottom plate 1; the rear baffle 3 is vertically arranged between the rear frame of the upper frame 4 and the lower bottom plate 1; the front noise reduction pipe group 5 is vertically arranged between the front frame of the upper frame 4 and the lower bottom plate 1; the right noise reduction pipe group 6 is vertically arranged between the right frame of the upper frame 4 and the lower bottom plate 1; the upper noise reduction pipe group 7 is horizontally arranged between the front frame and the rear frame of the upper frame 4; a dust exhaust fan 8 is arranged in the middle of the rear baffle 3; the structure of the noise reduction pipe in the front noise reduction pipe group 5, the right noise reduction pipe group 6 and the upper noise reduction pipe group 7 is the same, coaxial nested double-pipe structures are adopted, the inner pipe and the outer pipe are reduced in noise, and the cross-sectional shapes of the inner pipe and the outer pipe are both C-shaped.

In the front noise reduction pipe group 5, the right noise reduction pipe group 6 and the upper noise reduction pipe group 7, the inner half part of the cross section of the noise reduction inner pipeLet us denote r₁And the outer radius of the cross section of the noise reduction inner pipe is recorded as r₂The inner radius of the cross section of the noise reduction outer pipe is recorded as R₁And the outer radius of the cross section of the noise reduction outer tube is recorded as R₂The utility model discloses a 3D printer, the opening width of making an uproar inner tube and making an uproar outer tube is equal and mark as K, the opening contained angle of making an uproar inner tube and making an uproar outer tube is 180, and the opening orientation 3D printer of making an uproar outer tube of making an uproar falls.

In the front noise reduction pipe group 5, the right noise reduction pipe group 6 and the upper noise reduction pipe group 7, the height of each noise reduction pipe is recorded as H, the distance between every two adjacent noise reduction pipes is recorded as L, and the outer radius of the cross section of each noise reduction outer pipe is recorded as R₂And L is 2R₂(ii) a The height H of the noise reduction pipe is 50 mm-500 mm.

When the central frequency of the noise is 1300 Hz-1400 Hz, the inner radius r of the cross section of the noise reduction inner pipe₁Is 5mm, and the outer radius r of the cross section of the noise reduction inner pipe₂8.5 mm-9.5 mm, and the inner radius R of the cross section of the noise reduction outer pipe₁12 mm-14 mm, and the outer radius R of the cross section of the noise reduction outer tube₂19mm, and the opening width K of the noise reduction inner tube and the noise reduction outer tube is 4.5 mm.

When the noise center frequency is 1400 Hz-1500 Hz, the inner radius r of the cross section of the noise reduction inner pipe₁Is 5mm, and the outer radius r of the cross section of the noise reduction inner pipe₂7.5 mm-8.5 mm, and the inner radius R of the cross section of the noise reduction outer tube₁Is 11 mm-12 mm, and the outer radius R of the cross section of the noise reduction outer tube₂Is 19mm, and the opening width K of the noise reduction inner tube and the noise reduction outer tube is 5 mm.

When the noise center frequency is 1500 Hz-1600 Hz, the inner radius r of the cross section of the noise reduction inner pipe₁Is 5mm, and the outer radius r of the cross section of the noise reduction inner pipe₂6.5 mm-7.5 mm, and the inner radius R of the cross section of the noise reduction outer tube₁10 mm-11 mm, and the outer radius R of the cross section of the noise reduction outer tube₂19mm, and the opening width K of the noise reduction inner tube and the noise reduction outer tube is 5.5 mm.

When the noise center frequency is 1600 Hz-1700 Hz, the inner radius r of the cross section of the noise reduction inner pipe₁Is 5mm, and the outer radius r of the cross section of the noise reduction inner pipe₂6 mm-6.5 mm, and the inner radius R of the cross section of the noise reduction outer tube₁9 mm-10 mm, and noise reductionCross-sectional outer radius R of the tube₂Is 19mm, and the opening width K of the noise reduction inner tube and the noise reduction outer tube is 6 mm.

When the rotation angle of the noise reduction inner tube relative to the noise reduction outer tube is adjustable, the opening included angle of the noise reduction inner tube and the noise reduction outer tube is adjusted by adjusting the rotation angle of the noise reduction inner tube so as to change the noise center frequency which can be restrained by the noise reduction tube.

When the cross section inner radius r of the noise reduction inner pipe₁Is 5mm, and the section outer radius r of the noise reduction inner pipe₂8.5mm, and the inner radius R of the cross section of the noise reduction outer tube₁Is 12mm, and the section outer radius R of the noise reduction outer tube₂19mm, and the opening width K of the noise reduction inner pipe and the noise reduction outer pipe is 4.5mm, the opening included angle of the noise reduction inner pipe and the noise reduction outer pipe is changed between 180 degrees and 0 degrees, and then the center frequency of noise which can be inhibited by the noise reduction pipe is changed between 1386Hz and 1616 Hz.

Specifically, the method comprises the following steps: when the opening included angle of the noise reduction inner pipe and the noise reduction outer pipe is 180 degrees, the center frequency of noise which can be inhibited by the noise reduction pipe is 1386 Hz;

when the opening included angle between the noise reduction inner tube and the noise reduction outer tube is 150 degrees, the center frequency of noise which can be suppressed by the noise reduction tube is 1394 Hz;

when the included angle of the openings of the noise reduction inner tube and the noise reduction outer tube is 120 degrees, the center frequency of noise which can be suppressed by the noise reduction tube is 1417 Hz;

when the included angle of the openings of the noise reduction inner tube and the noise reduction outer tube is 90 degrees, the center frequency of noise which can be suppressed by the noise reduction tube is 1457 Hz;

when the included angle of the openings of the noise reduction inner pipe and the noise reduction outer pipe is 60 degrees, the center frequency of noise which can be suppressed by the noise reduction pipe is 1515 Hz;

when the included angle of the openings of the noise reduction inner tube and the noise reduction outer tube is 30 degrees, the center frequency of noise which can be suppressed by the noise reduction tube is 1587 Hz;

when the opening included angle of the noise reduction inner tube and the noise reduction outer tube is 0 degree, the noise center frequency which can be restrained by the noise reduction tube is 1616 Hz.

The lower bottom plate 1, the left baffle plate 2 and the rear baffle plate 3 are all made of acrylic plates; the upper frame 4 is made of aluminum alloy; the noise reduction inner pipe and the noise reduction outer pipe are made of resin.

After a certain 3D printer adopts the noise suppression structure, the detection shows that the noise center frequency of the 3D printer is 1457Hz, so that the noise center frequency is just in the range of 1400 Hz-1500 Hz, and the inner radius r of the cross section of the noise reduction inner tube can be directly selected₁Is 5mm, and the section outer radius r of the noise reduction inner pipe₂7.5 mm-8.5 mm, and the inner radius R of the section of the noise reduction outer tube₁Is 11 mm-12 mm, and the outer radius R of the section of the noise reduction outer tube₂The noise reduction pipe scheme that the opening width K of the noise reduction inner pipe and the noise reduction outer pipe is 19mm is 5mm, or the section inner radius r of the noise reduction inner pipe can be directly selected₁Is 5mm, and the section outer radius r of the noise reduction inner pipe₂8.5mm, and the inner radius R of the cross section of the noise reduction outer tube₁Is 12mm, and the section outer radius R of the noise reduction outer tube₂The noise reduction tube scheme is that the opening width K of the noise reduction inner tube and the noise reduction outer tube is 4.5mm, the opening included angle between the noise reduction inner tube and the noise reduction outer tube is 90 degrees by rotating the noise reduction inner tube, and the noise reduction tube can just restrain the noise with the noise center frequency of 1457 Hz.

In addition, when the noise suppression structure is used for reducing noise of the 3D printer, the dust exhaust fan 8 can be synchronously started, the air outlet of the dust exhaust fan 8 is communicated with the dust removal channel, heat dissipation can be realized in a natural convection mode by combining the open cavity structure under the action of the dust exhaust fan 8, and meanwhile dust generated by the 3D printer can be discharged into the dust removal channel from the dust exhaust fan 8 along with convection wind, so that the problem of dust pollution is solved.

The embodiments are not intended to limit the scope of the present invention, and all equivalent implementations or modifications without departing from the scope of the present invention are intended to be included in the scope of the present invention.