CN110030720B - Medium-high frequency silencer with cavity filled with bulk spheres - Google Patents
Medium-high frequency silencer with cavity filled with bulk spheres Download PDFInfo
- Publication number
- CN110030720B CN110030720B CN201910340386.3A CN201910340386A CN110030720B CN 110030720 B CN110030720 B CN 110030720B CN 201910340386 A CN201910340386 A CN 201910340386A CN 110030720 B CN110030720 B CN 110030720B
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- Prior art keywords
- cavity
- air inlet
- air
- spherical particles
- high frequency
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- 230000003584 silencer Effects 0.000 title claims abstract description 15
- 239000012798 spherical particle Substances 0.000 claims abstract description 38
- 230000030279 gene silencing Effects 0.000 claims description 22
- 238000005192 partition Methods 0.000 claims description 5
- 239000011521 glass Substances 0.000 claims description 4
- 239000000919 ceramic Substances 0.000 claims description 3
- 239000002184 metal Substances 0.000 claims description 3
- 230000000694 effects Effects 0.000 abstract description 6
- 238000000034 method Methods 0.000 abstract description 2
- 230000008030 elimination Effects 0.000 abstract 1
- 238000003379 elimination reaction Methods 0.000 abstract 1
- 238000001514 detection method Methods 0.000 description 5
- 239000002245 particle Substances 0.000 description 5
- 230000001743 silencing effect Effects 0.000 description 3
- 208000009205 Tinnitus Diseases 0.000 description 1
- 239000011324 bead Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 231100000886 tinnitus Toxicity 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
- F24F13/24—Means for preventing or suppressing noise
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
- F24F13/24—Means for preventing or suppressing noise
- F24F2013/242—Sound-absorbing material
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
The invention provides a medium-high frequency silencer with a cavity filled with bulk spheres, which comprises a shell, wherein a hollow cavity is formed in the shell, a plurality of spherical particles are filled in the cavity, an air inlet and an air outlet which are communicated with the cavity are formed in the side wall of the shell, an air flow is sucked by a fan arranged outside the shell through the air inlet and is discharged through the air outlet after passing through the spherical particles in the cavity, and included angle gaps with radians are formed among the spherical particles in the cavity in contact, so that after the air flow passes through the medium-high frequency sound waves can be inhibited. According to the invention, the plurality of spherical particles which are mutually clung are distributed in the cavity of the shell, so that the squeaking sounds (middle and high frequency noises) of the entering air flow can be effectively removed, the problem that the middle and high frequency noises which cannot be solved by the existing fresh air system for a long time are difficult to eliminate is solved, and compared with the prior art, the novel fresh air system has the advantages of simple process, low realization cost and excellent elimination effect.
Description
Technical Field
The invention relates to the technical field of noise reduction, in particular to a medium-high frequency noise reduction device with a cavity filled with bulk spheres.
Background
The fresh air system is based on the principle that a 'fresh air flow field' is formed indoors according to the principle that fresh air is sent indoors by special equipment on one side of a closed indoor and then discharged outdoors from the special equipment on the other side, so that the indoor fresh air ventilation requirement is met. The implementation scheme is as follows: a high-pressure head, a high-flow low-power direct-current high-speed brushless motor is adopted to drive a centrifugal fan, one side is used for supplying air indoors by means of mechanical strength, and the other side is used for forcing a fresh air flow field to be formed in the system in a mode of exhausting the fresh air fan which is specially designed outdoors. The fresh air is filtered, sterilized, oxygenated and preheated (in winter) while the air is supplied. When the exhaust air passes through the host machine, heat recovery exchange is carried out with the fresh air, and most of recovered energy is sent back to the room through the fresh air.
At present, a plurality of families can be provided with a fresh air system, so that the indoor air quality can be ensured, but after the fresh air system is arranged, the indoor noise is troublesome. The noise of the fresh air system mainly comes from the noise of the main engine and the noise of the wind mouth, wherein a part of the noise of the main engine is the noise of the motor operation, and a part of the noise is the noise generated by the high-speed flow of wind, and the noise of the main engine operation basically does not need worry by selecting a motor with over-hard quality; wind gap noise, namely wind noise, needs to be low enough under the precursor that satisfies the amount of wind sufficient, and centrifugal fan (adopting vortex fan) among the current fresh air system amortizes effectually, and the noise still is very big, and the middle-high frequency noise that especially fan produced (what is known as a similar tinnitus's whistle) is difficult to eliminate.
Disclosure of Invention
The invention provides a medium-high frequency silencing device with a cavity filled with bulk spheres, which can effectively eliminate medium-high frequency noise generated by a fan, and has the advantages of simple structure, low realization cost and good effect.
The utility model provides a well high frequency silencing device of cavity filling bulk spheroid, includes the casing, forms inside hollow cavity in the casing, the cavity intussuseption is filled with a plurality of globular particles, the casing lateral wall forms air intake and the air outlet with the cavity intercommunication, locates the outside fan of casing and inhales the air current by the air intake, discharges by the air outlet after globular particle in the cavity, contacts between globular particle in the cavity and forms the contained angle space that has the radian, and the sound wave of medium-high frequency can be restrained after the air current passes through.
Further, the casing is an upper opening, the lower part is concave arc bottom plate's cavity type structure, the inner chamber of casing is separated into exhaust cavity and air inlet cavity by the middle part baffle, and wherein the lateral wall of exhaust cavity is equipped with exhaust cavity gas outlet, and the fan gas vent has been seted up to the arc bottom plate of exhaust cavity bottom, and the lateral wall of air inlet cavity is equipped with the air inlet cavity air inlet, and the fan air inlet has been seted up to the bottom plate of air inlet cavity bottom, and spherical granule is packed into to exhaust cavity and air inlet cavity, and the fan is installed with the concave part cooperation of arc bottom plate.
Further, negative pressure generated by the fan sucks air flow from an air inlet of an air inlet cavity on the side wall of the air inlet cavity, the air flow enters an air inlet of the fan from the air inlet of the fan at the bottom of the air inlet cavity after being noise-reduced through spherical particles in the air inlet cavity, the air flow enters the air outlet cavity from an air outlet of the fan at the bottom of the air outlet cavity after entering the fan, and the air flow is sent out from an air outlet of the air outlet cavity on the side wall after being noise-reduced through spherical particles in the air outlet cavity.
Further, the diameter of the spherical particles is 3-50mm.
Further, the diameter of the spherical particles was 7.5mm.
Further, the spherical particles are made of glass or ceramic.
Further, meshes are paved on the inner side walls of the exhaust cavity and the air inlet cavity, and the diameters of the meshes are smaller than those of the spherical particles.
Further, the mesh is a metal mesh or a plastic mesh.
Further, two sides of the middle partition plate of the shell are respectively provided with a first silencing felt and a second silencing felt hinged with the first silencing felt, and the second silencing felt can be bent to seal the upper opening of the air inlet cavity or the air outlet cavity.
Further, an upper opening of the housing is sealed with a cover plate.
According to the invention, through arranging the plurality of spherical particles which are mutually clung in the cavity of the shell, the squeaking sounds (middle and high frequency noises) of the entering air flow can be effectively removed, the problem that the middle and high frequency noises which cannot be solved by the existing fresh air system for a long time are difficult to eliminate is solved, and the satisfied detection result is obtained by professional detection of an actual product.
Drawings
FIG. 1 is a schematic perspective view of a portion of the structure of an embodiment of a medium and high frequency muffler device with cavity-filled bulk spheres in accordance with the present invention;
FIG. 2 is a schematic perspective view of a portion of another embodiment of a mid-to-high frequency muffler device with cavity-filled bulk spheres in accordance with the present invention;
FIG. 3 is a schematic view of an exploded view of a first embodiment of a medium and high frequency muffler device with cavity-filled bulk spheres in accordance with the present invention;
FIG. 4 is a schematic illustration of an embodiment of the mid-to-high frequency muffler device of the present invention with cavity-filled bulk spheres in use;
FIG. 5 is a schematic perspective view of a two-part structure of an embodiment of a medium and high frequency muffler device with cavity-filled bulk spheres in accordance with the present invention;
FIG. 6 is a graph showing the frequency bands of sound in a room measured before the silencer according to the present invention is not used;
FIG. 7 is a graph showing the distribution of the frequency bands of the sound in the room measured by using the silencer according to the present invention.
In the figure: 1-shell, 2-exhaust cavity, 3-intake cavity, 4-bottom plate, 5-exhaust cavity gas outlet, 6-fan gas outlet, 7-intake cavity gas inlet, 8-fan gas inlet, 9-net, 10-spherical particles, 11-cover plate, 12-fan, 13-first noise reduction felt, 14-second noise reduction felt.
Detailed Description
The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings.
Referring to fig. 1-3, the present invention provides a middle-high frequency silencing device with a cavity filled with bulk spheres, wherein one embodiment of the middle-high frequency silencing device comprises a shell 1, wherein a hollow cavity is formed in the shell 1, a plurality of spherical particles 10 are filled in the cavity, an air inlet and an air outlet communicated with the cavity are formed in the side wall of the shell 1, an air flow is sucked by a fan arranged outside the shell 1 through the air inlet, and is discharged through the air outlet after passing through the spherical particles 10 in the cavity, included angle gaps with radians are formed between the spherical particles 10 in the cavity, and when air flows through the air flow, sound waves of middle-high frequency are inhibited, so that a better silencing effect is achieved.
Specifically, in one embodiment, the housing 1 is a cavity structure with an upper opening and a lower concave arc-shaped bottom plate 4, and the cavity of the housing 1 is divided into an exhaust cavity 2 and an air inlet cavity 3 by a middle partition plate, wherein the side wall of the exhaust cavity 2 is provided with an exhaust cavity air outlet 5, the bottom plate 4 at the bottom of the exhaust cavity 2 is provided with a fan air outlet 6, and correspondingly, the side wall of the air inlet cavity 3 is provided with an air inlet cavity air inlet 7, and the bottom plate 4 at the bottom of the air inlet cavity 3 is provided with a fan air inlet 8.
As shown in FIG. 3, the exhaust cavity 2 and the air inlet cavity 3 are filled with spherical particles 10, the diameter of each spherical particle 10 is 3-50mm, 7.5mm is adopted in the embodiment, the material is glass or ceramic, the number of the glass beads is about 3000 in the embodiment, and about 1500 of the exhaust cavity 2 and the air inlet cavity 3 are respectively arranged. In order to avoid that the spherical particles 10 leak out of the exhaust chamber 2 and the intake chamber 3 or roll to affect the sound deadening effect, a net 9, such as a metal net, a plastic net, or the like, whose mesh diameter is smaller than the diameter of the spherical particles 10 may be laid on the inner side walls of the exhaust chamber 2 and the intake chamber 3 so that the spherical particles 10 do not leak out of the net 9.
When the device is used, referring to fig. 3 and 4 in combination, after spherical particles 10 are filled into the exhaust cavity 2 and the air inlet cavity 3, an upper opening of the shell 1 is sealed by using a cover plate 11 to form a medium-high frequency silencing device with the cavity filled with bulk spheres, then the shell is turned over to enable a bottom plate 4 of the shell 1 to face upwards, a fan 12 is arranged on the shell 1, the fan 12 is just matched with a concave part of the arc-shaped bottom plate 4, a fan air inlet 8 is correspondingly communicated with the air inlet cavity 3, and a fan air outlet 6 is correspondingly communicated with the air outlet cavity 2. When the air conditioner works, negative pressure generated by the fan 12 sucks air flow from the air inlet cavity air inlet 7 on the side wall of the air inlet cavity 3, the air flow enters the air inlet of the fan 12 from the fan air inlet 8 on the bottom of the air inlet cavity 3 after noise reduction of spherical particles 10 in the air inlet cavity 3, the air flow enters the air outlet of the fan 12 and then enters the air outlet cavity 2 from the fan air outlet 6 on the bottom of the air outlet cavity 2 from the air outlet of the fan 12, and the air flow is sent out from the air outlet 5 of the air outlet cavity on the side wall after noise reduction of the spherical particles 10 in the air outlet cavity 2.
Referring to fig. 5, in another embodiment, two sides of the middle partition board of the housing 1 are respectively provided with a first silencing felt 13 and a second silencing felt 14 hinged with the first silencing felt 13, and the second silencing felt 14 can be bent to cover the upper opening of the air inlet cavity 3 or the air outlet cavity 2, as shown in fig. 5, and the upper opening of the air outlet cavity 2 is sealed by the second silencing felt 14. The arrangement of the first silencing felt 13 and the second silencing felt 14 can better limit the spherical particles 10 in the cavity, prevent the spherical particles 10 from shaking in the cavity, and more importantly enhance the silencing effect.
Compared with the prior art, the invention has the beneficial effects that: according to the medium-high frequency silencing device with the cavity filled with the bulk spherical bodies, the spherical particles 10 with the particle size of 3-5mm are used as the sound absorbing component, the spherical particles with the particle size have a good scattering effect on noise sound waves, the spherical particles 10 are in contact to form included angle gaps with radians, and when the sound waves are continuously reflected in the included angle gaps after air flow passes through, the high-frequency sound waves can be inhibited, so that a good silencing effect is achieved.
The invention is an effective technical scheme which is researched and developed by the inventor in the actual production development process, solves the problem that the medium-high frequency noise which is not solved for a long time in the existing fresh air system is difficult to eliminate, and the actual product obtains a satisfactory detection result through professional detection: when the silencer is not used, the fan detects that the indoor noise is 95.1 dB (the national specified value of the indoor environment noise of residents cannot exceed 50 dB in daytime and 45 dB at night) when the silencer is operated at the maximum power, the indoor noise is detected to be only 29.8 dB after the silencer is used, the noise reduction effect is very obvious, and the main reason is that the human ear is most sensitive to the sound of 2-5 kHz, and the design of the invention obviously eliminates the high-frequency sound near 2k (shown in figure 7), namely the indoor noise is greatly reduced. In addition, after the silencer of the invention is installed, the air flow has no obvious resistance effect, namely the air outlet speed of the fan is not influenced, and the air pressure of the air outlet can reach after the actual detection
The foregoing is merely illustrative embodiments of the present invention, and the present invention is not limited thereto, and any changes or substitutions that may be easily contemplated by those skilled in the art within the scope of the present invention should be included in the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.
Claims (8)
1. The utility model provides a well high frequency silencing device of cavity filling bulk spheroid which characterized in that: the device comprises a shell (1), wherein a hollow cavity is formed in the shell (1), a plurality of spherical particles (10) are filled in the cavity, an air inlet and an air outlet which are communicated with the cavity are formed in the side wall of the shell (1), an air flow is sucked by a fan arranged outside the shell (1) through the air inlet and is discharged through the air outlet after passing through the spherical particles (10) in the cavity, the spherical particles (10) in the cavity are contacted to form included angle gaps with radian, and after the air flow passes through the air flow, sound waves with medium and high frequencies can be restrained; the shell (1) is of a cavity structure with an upper opening and a concave arc-shaped bottom plate (4) at the lower part, the inner cavity of the shell (1) is divided into an exhaust cavity (2) and an air inlet cavity (3) by a middle partition plate, the side wall of the exhaust cavity (2) is provided with an exhaust cavity air outlet (5), the arc-shaped bottom plate (4) at the bottom of the exhaust cavity (2) is provided with a fan air outlet (6), the side wall of the air inlet cavity (3) is provided with an air inlet cavity air inlet (7), the bottom plate (4) at the bottom of the air inlet cavity (3) is provided with a fan air inlet (8), the exhaust cavity (2) and the air inlet cavity (3) are filled with spherical particles (10), and a fan (12) is matched with the concave part of the arc-shaped bottom plate (4); the diameter of the spherical particles (10) is 3-50mm.
2. The medium-high frequency silencer of cavity-filled bulk spheres as recited in claim 1, wherein: negative pressure generated by the fan (12) sucks air flow from an air inlet cavity air inlet (7) on the side wall of the air inlet cavity (3), the air flow enters an air inlet of the fan (12) from a fan air inlet (8) on the bottom of the air inlet cavity (3) after noise reduction of spherical particles (10) in the air inlet cavity (3), the air flow enters the fan (12) and then enters the air outlet cavity (2) from a fan air outlet (6) on the bottom of the air outlet cavity (2) from an air outlet of the fan (12), and the air flow is sent out from an air outlet (5) of the air outlet cavity on the side wall after noise reduction of the spherical particles (10) in the air outlet cavity (2).
3. The medium-high frequency silencer of cavity-filled bulk spheres as recited in claim 1, wherein: the diameter of the spherical particles (10) is 7.5mm.
4. The medium-high frequency silencer of cavity-filled bulk spheres as recited in claim 1, wherein: the spherical particles (10) are made of glass or ceramic.
5. The medium-high frequency silencer of cavity-filled bulk spheres as recited in claim 1, wherein: the inner side walls of the exhaust cavity (2) and the air inlet cavity (3) are paved with meshes (9), and the diameters of the meshes (9) are smaller than those of the spherical particles (10).
6. The medium and high frequency sound attenuating device of claim 5, wherein the cavity-filled bulk spheres comprise: the net (9) is a metal net or a plastic net.
7. The medium-high frequency silencer of cavity-filled bulk spheres as recited in claim 1, wherein: the two sides of the middle partition plate of the shell (1) are respectively provided with a first silencing felt (13) and a second silencing felt (14) hinged with the first silencing felt (13), and the second silencing felt (14) can be bent to cover the upper opening of the air inlet cavity (3) or the air outlet cavity (2).
8. The medium-high frequency silencer of cavity-filled bulk spheres as recited in claim 1, wherein: the upper opening of the housing (1) is sealed with a cover plate (11).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910340386.3A CN110030720B (en) | 2019-04-25 | 2019-04-25 | Medium-high frequency silencer with cavity filled with bulk spheres |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910340386.3A CN110030720B (en) | 2019-04-25 | 2019-04-25 | Medium-high frequency silencer with cavity filled with bulk spheres |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110030720A CN110030720A (en) | 2019-07-19 |
| CN110030720B true CN110030720B (en) | 2024-02-06 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910340386.3A Active CN110030720B (en) | 2019-04-25 | 2019-04-25 | Medium-high frequency silencer with cavity filled with bulk spheres |
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| Country | Link |
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| CN (1) | CN110030720B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113775572B (en) * | 2021-08-25 | 2023-09-26 | 湖南泛航智能装备有限公司 | Noise reduction structure and noise reduction method for high-speed high-pressure centrifugal blower |
| CN114001420B (en) * | 2021-10-27 | 2023-07-04 | 上海民航新时代机场设计研究院有限公司 | New fan of low noise total heat net effect |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10299115A (en) * | 1997-04-28 | 1998-11-10 | Heisei Sangyo:Kk | Sound absorbing material, sound absorbing device and sound absorbing material installing construction method |
| US6089348A (en) * | 1999-09-22 | 2000-07-18 | Bokor Manufacturing Inc. | Blower noise silencer |
| US8684131B1 (en) * | 2012-12-12 | 2014-04-01 | Kia Motors Corporation | Dual muffler |
| CN105485793A (en) * | 2015-12-25 | 2016-04-13 | 广东美的制冷设备有限公司 | Compressor assembly, outdoor unit and air conditioner |
| CN206656482U (en) * | 2017-04-24 | 2017-11-21 | 浙江方宏空调设备有限公司 | A kind of trumpet type silencer of air conditioning for automobiles |
| CN209877323U (en) * | 2019-04-25 | 2019-12-31 | 沈志伟 | Medium-high frequency silencer with cavity filled with bulk spheres |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090229913A1 (en) * | 2008-02-08 | 2009-09-17 | Waldron's Antique Exhaust | Dual Mode Exhaust Muffler |
-
2019
- 2019-04-25 CN CN201910340386.3A patent/CN110030720B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10299115A (en) * | 1997-04-28 | 1998-11-10 | Heisei Sangyo:Kk | Sound absorbing material, sound absorbing device and sound absorbing material installing construction method |
| US6089348A (en) * | 1999-09-22 | 2000-07-18 | Bokor Manufacturing Inc. | Blower noise silencer |
| US8684131B1 (en) * | 2012-12-12 | 2014-04-01 | Kia Motors Corporation | Dual muffler |
| CN105485793A (en) * | 2015-12-25 | 2016-04-13 | 广东美的制冷设备有限公司 | Compressor assembly, outdoor unit and air conditioner |
| CN206656482U (en) * | 2017-04-24 | 2017-11-21 | 浙江方宏空调设备有限公司 | A kind of trumpet type silencer of air conditioning for automobiles |
| CN209877323U (en) * | 2019-04-25 | 2019-12-31 | 沈志伟 | Medium-high frequency silencer with cavity filled with bulk spheres |
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| Publication number | Publication date |
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| CN110030720A (en) | 2019-07-19 |
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