CN104595251A - Silencer for lampblack fan - Google Patents
Silencer for lampblack fan Download PDFInfo
- Publication number
- CN104595251A CN104595251A CN201410706029.1A CN201410706029A CN104595251A CN 104595251 A CN104595251 A CN 104595251A CN 201410706029 A CN201410706029 A CN 201410706029A CN 104595251 A CN104595251 A CN 104595251A
- Authority
- CN
- China
- Prior art keywords
- noise elimination
- noise
- blade
- silencing apparatus
- muffling unit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
- F04D29/661—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps
- F04D29/663—Sound attenuation
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
- F04D29/661—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps
- F04D29/663—Sound attenuation
- F04D29/664—Sound attenuation by means of sound absorbing material
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
The invention discloses a silencer for a lampblack fan. The silencer comprises a first silencing unit, a second silencing unit and a transition section, wherein silencing blades are arranged in the first silencing unit and the second silencing unit, the transition section is hollow and is provided with no silencing blade, and the silencing blades are divided into a front section and a rear section in the airflow direction. The silencing blades on the front section and the silencing blades on the rear section are arranged in a stagger mode, so that insertion loss of the whole silencer is effectively increased, silencing effect is remarkable, wide-band noise silencing effect is especially remarkable, and the silencer is suitable for equipment with high noise such as the lampblack fan.
Description
Technical field
The invention belongs to silencing equipment, particularly relating to a kind of lampblack fan silencing apparatus for eliminating lampblack fan noise.
Background technique
Along with the development of China's city process, City complex turns the main construction trend of modern city into, and catering trade, as the critical function part of City complex, has now become the most important thing that current composite body is promoted trade and investment.Along with the garrison of food and drink, the noise of kitchen fume blower fan and oil smoke problem drastically influence the living environment of owner.
Huge discharge lampblack fan noise is higher, and frequency characteristic is Low Medium Frequency characteristic.Low Medium Frequency noise attentuation is comparatively slow, low-frequency noise blower fan on the impact of surrounding environment than middle height quite noise blower fan impact more greatly; Existing sound insulation and silencing equipment are weak links to low-frequency noise, namely to sound insulation and the soundproof effect difference of all-bottom sound; Lampblack fan noise not only brings certain difficulty to noise abatement, and control expense is obviously higher simultaneously.
General pipeline silencer, its noise elimination blade easily adsorbs oil smoke, and the time has been grown, and soundproof effect can reduce.
As patent application 01234999.2 discloses a kind of oil resistant water silencer.The sound insulation part of this oil resistant water silencer is by thickening phosphorus magnesium plate, and reinforced pitch as binder and oil resistant rubber bond, and use laminated glass cellucotton, by polyvinyl chloride panel and acetic acid plate through resin-bonded, on panel uniform 60% conical apertures.Mesosphere between oil removal water section and sound-absorbing part, is overrided to form by the ball warp high-temperature agglomerant of moulding of different-grain diameter, whole oil removal water section spraying antitack agent.But above-mentioned structure adopts polyvinyl chloride panel and acetic acid plate to make, resistance to high temperature is poor, and filters soundproof effect in practical application and not obvious.
Summary of the invention
The technical problem to be solved in the present invention is, for the above-mentioned defect of prior art, provides a kind of lampblack fan silencing apparatus, and this silencing apparatus soundproof effect is remarkable, and especially broadband noise soundproof effect is obvious, is applicable to the equipment that noise is larger, as lampblack fan etc.
Be to provide a kind of lampblack fan silencing apparatus, this silencing apparatus segment design another order of the present invention, increase the path of noise attentuation, strengthen noise reduction, and effectively reduce regenerated noise and the pressure drop of silencing apparatus.
For achieving the above object, the present invention realizes in the following manner.
A kind of lampblack fan silencing apparatus, it is characterized in that this silencing apparatus includes the first muffling unit, the second muffling unit and changeover portion three parts, be equiped with noise elimination blade respectively in wherein said first muffling unit, the second muffling unit, changeover portion is then hollow structure, does not arrange noise elimination blade.
Described noise elimination blade adopts the design of contracting tail, and namely the front end of described noise elimination blade and rear end are streamline structure, and one is convenient to passing through smoothly of air-flow, can effectively reduce pressure drop and regenerated noise.
Further, the noise elimination blade in described first muffling unit, arranges as both sides are half noise elimination blade, and middle is blade of entirely eliminating the noise, and uniform intervals distributes, and wherein the thickness of half anechoic sheet is the half of full anechoic sheet thickness; Noise elimination blade in second muffling unit is then blade of entirely eliminating the noise.
Further, in described second muffling unit, noise elimination blade arrangement is both sides is hemichannel, centre is uniformly distributed for full noise elimination blade, namely silencing channel width in both sides is the half of middle silencing channel width, noise elimination blade stagger in noise elimination blade and the first muffling unit distributes, and increases the path of noise attentuation, strengthens noise reduction.
Further, the front end of described noise elimination blade is windward side, and windward side is the air guide sleeve of streamline structure, is provided with perforated plate after air guide sleeve, and noise elimination blade take perforated plate as mask; The sound-absorbing material such as filling glass cotton or rock wool in perforated plate, the afterbody of noise elimination blade also has the structure same with perforated plate, and is airflow design.Noise elimination vane thickness is 100 ~ 400mm, can according to the spectral characteristics of noise of blower fan, the thickness of adjustment noise elimination blade.
Described noise elimination blade is the noise elimination blade of wedge shape, and air guide sleeve and afterbody are sharp-pointed shape structure, form wedge-shaped structure together with perforated plate.
Described sound-absorbing material, its outer surface is enclosed with polyester film, in order to prevent oil smoke pollution sound-absorbing material, prevents silencing apparatus soundproof effect from reducing.
Described changeover portion is the airduct of plugging into of connection first muffling unit and the second muffling unit, and do not eliminate the noise blade in inside, the shell of changeover portion and the first muffling unit, the second muffling unit shell are consistent, and flow through to make uniform stream.
The caliber of described first muffling unit and the second muffling unit shell is consistent.
Lampblack fan silencing apparatus designed by the present invention is a kind of impedance type rectangle silencing apparatus, its noise elimination blade divides two sections, front and back by airflow direction, the dislocation design of front and back noise elimination blade, effectively increase the insertion loss of silencing apparatus entirety, soundproof effect is remarkable, especially broadband noise soundproof effect is obvious, is applicable to the equipment that noise is larger, as lampblack fan etc.
Accompanying drawing explanation
Fig. 1 is the plan view of the lampblack fan silencing apparatus that the present invention implements.
Fig. 2 is the sectional view of structure shown in Fig. 1.
Fig. 3 is the structural representation of noise elimination blade.
Embodiment
Below in conjunction with accompanying drawing, technical solution of the present invention is described in detail:
As shown in Figure 1 and Figure 2, the lampblack fan silencing apparatus that the present invention realizes, mainly includes three parts: noise elimination A section 1 (the first muffling unit), noise elimination B section 3 (the second muffling unit) and changeover portion 2.
Wherein, noise elimination A section 1 is designed to rectangle silencing apparatus, is made up of shell 7 and noise elimination blade 5,6.Noise elimination blade arrangement is both sides is half noise elimination blade 5, and centre is that full noise elimination blade 6, half noise elimination blade 5 and full noise elimination blade 6 are evenly distributed; The thickness of half anechoic sheet is the half of full anechoic sheet thickness, and be fixed on the inwall of shell 7,6, full noise elimination blade is from being vertically fixed in shell.Noise elimination blade 5,6 quantity is comprehensively determined depending on actual noise reduction requirement, airduct size and pressure drop permitted value, is generally 5-10 sheet (ventilation ratio is generally 40%-60%), can require to increase and decrease according to erecting bed.
Noise elimination B section 3 also designs rectangle silencing apparatus, and its caliber is consistent with noise elimination A section.Be made up of shell 7 and noise elimination blade 6, its noise elimination blade is full noise elimination blade 6.On most limit two noise elimination blades 6 and shell sidewall be spaced apart hemichannel, centre is evenly distributed for full noise elimination blade 6, and (the silencing channel width namely near side wall of outer shell both sides is the half of middle silencing channel width, the noise elimination blade 6 of noise elimination B section 3 is made just to be in staggered distribution with the noise elimination blade 6 of noise elimination A section 1 like this, to increase the path of noise attentuation, strengthen noise reduction).
Noise elimination blade 6 due to noise elimination B section 3 blade of eliminating the noise is full noise elimination blade 6, therefore when its full noise elimination vane thickness is consistent with noise elimination A section, more than noise elimination A section one of its noise elimination blade quantity, but partly do not eliminate the noise blade.
Changeover portion 2 is the airducts of plugging into connecting noise elimination A section and noise elimination B section, and do not eliminate the noise blade in inside, its shell is consistent with noise elimination A, B section shell, and length is generally 100mm ~ 500mm.
Airflow direction: from noise elimination A section (the first muffling unit) through transition tube to noise elimination B section (the second muffling unit).Lampblack fan silencing apparatus respectively adopts two muffler section structure, and centre is changeover portion.Noise of equipment is propagated in pipeline, and along with airflow direction is first through noise elimination A section, noise is necessarily decayed; Be transmitted to changeover portion again to enter noise elimination B section noise and decay further.
The Placement of noise elimination A section 1, noise elimination B section 3 and changeover portion 2 is: connect with GB angle iron flange 4 between noise elimination A section, changeover portion, noise elimination B section.
Again shown in composition graphs 3, the front end of noise elimination blade 6 is windward side, and windward side is the air guide sleeve 8 of streamline structure, is provided with perforated plate 9 after air guide sleeve 8, with perforated plate 9 for mask; Perforated plate 9 surface has a plurality of micropunch, and the sound-absorbing materials 10 such as interior filling glass cotton or rock wool, the afterbody 11 of noise elimination blade also has the structure same with perforated plate.Noise elimination vane thickness is generally 100 ~ 400mm, can according to the spectral characteristics of noise of blower fan, the thickness of adjustment noise elimination blade.
Especially, it should be noted that, air guide sleeve 8 adopts sharp-pointed head construction, be conducive to air-flow to pass through, afterbody 11 also adopts contracting tail to design, also the structure of sharp-pointed shape is designed to by afterbody 11, on the cross section of noise elimination blade 6, form the wedge shape shown in Fig. 3 like this, be conducive to passing through of air-flow, can effectively reduce pressure drop and regenerated noise.
In other embodiments, air guide sleeve 8 and afterbody 11 also all can be designed to other streamline structure.
Be enclosed with one deck polyester film 12 at sound-absorbing material 10 outer surface, polyester film 12 can prevent oil smoke pollution sound-absorbing material, prevents silencing apparatus soundproof effect from reducing.
The mechanism of action of the present invention is as follows:
In noise elimination A section 1: in establish some noise elimination blades, noise absorbs at noise elimination A section portion of energy blade of being eliminated the noise, and noise is decayed, and according to blower fan spectral characteristic, the thickness of adjustment noise elimination blade, can to the noise elimination effect targetedly of the noise of different spectral characteristic.
At changeover portion 2: changeover portion is similar to the effect of small-sized static case.Aerodynamic energy is converted into static pressure, promotes static pressure, air is flowed and becomes slowly uniform and stable, make air-supply effect more desirable.Reduce airstream vibration, soundproof effect also can correspondingly improve simultaneously.
In noise elimination B section 3: the decay of single silencing apparatus to noise is relatively limited, for the silencing apparatus that the equipment that noise is large needs insertion loss larger.The composite structure that noise elimination B section is in staggered distribution by noise elimination blade structure and noise elimination A section noise elimination blade, increases soundproof effect, noise is decayed further in B section.
The present invention, by effective combination of noise elimination A section and B section, can make that the frequency of silencing apparatus is resistive to broaden targetedly, effectively to broadband noise characteristic fan noise elimination.Broadband properties noise, uses the silencing apparatus of traditional single structure, all needs the silencing apparatus grown to meet soundproof effect very much.Under the prerequisite meeting acoustical demands, silencing apparatus of the present invention can make the length of silencing apparatus shorten, thus saves noise reduction cost.
The material of shell 7 can be used: galvanized steel plain sheet, aluminium sheet, corrosion resistant plate etc., and can dust, lacquered surface process, thickness is 0.8 ~ 10mm.
Perforated plate 9 material can be used: zinc-plated hole sheet, aluminium hole sheet, stainless steel hole sheet etc., and can dust, lacquered surface process, thickness is 0.8 ~ 10mm.
Air guide sleeve 8 material can be used: galvanized steel plain sheet, aluminium sheet, corrosion resistant plate etc., and can dust, lacquered surface process, thickness 0.8 ~ 10mm.
Inner filling sucting sound material 10 can be used: glass wool, rock wool, polyester fibre, melamine etc., and density can be selected according to actual conditions, also can not fill (when not filling, the aperture of perforated plate will lower than 0.2mm).
Sound-absorbing material surface parcel material can be used: the waterproof and oilproof such as polyester film, cellophane cigarette thin polymer film.
Environmental Conditions is: the equipment airduct that cooking-fume discharging blower fan airduct, noise are larger, install the equipment of common silencing apparatus length limited.
By above-mentioned mode of execution, can find out, advantage of the present invention is:
1, silencing apparatus is resistance silencing apparatus, and acoustic attenuation performance is more remarkable than general single performance silencing apparatus soundproof effect, and especially broadband noise soundproof effect is obvious.
2, silencing apparatus divides two sections of noise elimination structures, and centre is connected by changeover portion; Establish noise elimination blade according to noise of equipment curve characteristic, different noise elimination vane thickness can be selected in noise elimination A section and B section.Low-frequency noise needs thicker noise elimination blade, and two sections of muffler sections for different frequency range noise can be complementary not enough, improves soundproof effect.
3, establish contracting tail type noise elimination blade in silencing apparatus, be conducive to the flowing of air-flow, effectively reduce regenerated noise and the pressure drop of silencing apparatus.
4, the noise elimination blade dislocation design of noise elimination A section and noise elimination B section, increases the path of noise attentuation, strengthens noise reduction.
5, sound-absorbing material surface increases one deck polyester film, can the corrosion to sound-absorbing material such as effective anti-sealing, dirt, oil smoke, extends the working life of silencing apparatus.
6, enclosure material can use galvanized sheet, aluminium sheet, corrosion resistant plate, and can dust, lacquered surface process, thickness is 0.8 ~ 10mm.
The above, be only the embodiment that the present invention enumerates, and can not limit of the invention processly comprise scope with this.All equalizations done according to the present patent application the scope of the claims change and modify, and all should belong in patent covering scope of the present invention.
Claims (9)
1. a lampblack fan silencing apparatus, it is characterized in that a kind of lampblack fan silencing apparatus, it is characterized in that this silencing apparatus includes the first muffling unit, the second muffling unit and changeover portion three parts, noise elimination blade is equiped with respectively in wherein said first muffling unit, the second muffling unit, changeover portion is then hollow structure, does not arrange noise elimination blade.
2. lampblack fan silencing apparatus as claimed in claim 1, is characterized in that the front end of described noise elimination blade and rear end are streamline structure.
3. lampblack fan silencing apparatus as claimed in claim 1, it is characterized in that the noise elimination blade in described first muffling unit, arrange as both sides are half noise elimination blade, middle is blade of entirely eliminating the noise, uniform intervals distributes, and wherein the thickness of half anechoic sheet is the half of full anechoic sheet thickness; Noise elimination blade in second muffling unit is then blade of entirely eliminating the noise.
4. lampblack fan silencing apparatus as claimed in claim 3, it is characterized in that in described second muffling unit, noise elimination blade arrangement is both sides is hemichannel, centre is uniformly distributed for full noise elimination blade, namely silencing channel width in both sides is the half of middle silencing channel width, noise elimination blade stagger in noise elimination blade and the first muffling unit distributes, and increases the path of noise attentuation, strengthens noise reduction.
5. lampblack fan silencing apparatus as claimed in claim 2, it is characterized in that the front end of described noise elimination blade is windward side, windward side is the air guide sleeve of streamline structure, is provided with perforated plate after air guide sleeve, and noise elimination blade take perforated plate as mask; In perforated plate, filling glass cotton or rock wool are as sound-absorbing material, and the afterbody of noise elimination blade also has the structure same with perforated plate, and are airflow design.
6. lampblack fan silencing apparatus as claimed in claim 5, it is characterized in that described noise elimination blade is the noise elimination blade of wedge shape, air guide sleeve and afterbody are sharp-pointed shape structure, form wedge-shaped structure together with perforated plate.
7. lampblack fan silencing apparatus as claimed in claim 5, it is characterized in that described sound-absorbing material, its outer surface is enclosed with polyester film.
8. lampblack fan silencing apparatus as claimed in claim 4, it is characterized in that described changeover portion is the airduct of plugging into of connection first muffling unit and the second muffling unit, do not eliminate the noise blade in inside, the shell of changeover portion and the first muffling unit, the second muffling unit shell are consistent, and flow through to make uniform stream.
9. lampblack fan silencing apparatus as claimed in claim 1, is characterized in that the caliber of described first muffling unit and the second muffling unit shell is consistent.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410706029.1A CN104595251A (en) | 2014-11-27 | 2014-11-27 | Silencer for lampblack fan |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410706029.1A CN104595251A (en) | 2014-11-27 | 2014-11-27 | Silencer for lampblack fan |
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| Publication Number | Publication Date |
|---|---|
| CN104595251A true CN104595251A (en) | 2015-05-06 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410706029.1A Pending CN104595251A (en) | 2014-11-27 | 2014-11-27 | Silencer for lampblack fan |
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| Country | Link |
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| CN (1) | CN104595251A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107702266A (en) * | 2017-11-02 | 2018-02-16 | 苏州纽塔克环境科技有限公司 | A kind of split type VMC of internal-external machine and installation method |
| CN109579895A (en) * | 2018-10-22 | 2019-04-05 | 山东省科学院海洋仪器仪表研究所 | A kind of bionical pod of blade combined type |
| CN113107932A (en) * | 2021-03-29 | 2021-07-13 | 株洲时代新材料科技股份有限公司 | Flow guide noise reduction sheet and flow guide noise reduction method of bent pipeline |
| WO2022127818A1 (en) * | 2020-12-18 | 2022-06-23 | 香港大学浙江科学技术研究院 | Extractor hood |
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| EP1624163A1 (en) * | 2004-08-06 | 2006-02-08 | Robert Bosch Gmbh | Sound insulating device especially for a heating apparatus |
| CN201184476Y (en) * | 2008-01-18 | 2009-01-21 | 蔡忠 | Pipeline silencer |
| US20110048846A1 (en) * | 2006-07-13 | 2011-03-03 | Compagnie Plastic Omnium | Noise attenuator for a hydraulic fluid pipe, item comprising this attenuator, pipe comprising this item and method of assembly |
| CN202117734U (en) * | 2011-06-24 | 2012-01-18 | 北京华旭佳音环保科技有限责任公司 | Impedance compound muffler with large wind volume |
| CN202228438U (en) * | 2011-09-09 | 2012-05-23 | 上海中驰建筑工程有限公司 | Compact sound absorption and noise reduction device of engine room ventilator of fishing boat |
| CN202991660U (en) * | 2012-10-29 | 2013-06-12 | 安徽宏发节能设备有限公司 | Silencing barrel |
-
2014
- 2014-11-27 CN CN201410706029.1A patent/CN104595251A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1624163A1 (en) * | 2004-08-06 | 2006-02-08 | Robert Bosch Gmbh | Sound insulating device especially for a heating apparatus |
| US20110048846A1 (en) * | 2006-07-13 | 2011-03-03 | Compagnie Plastic Omnium | Noise attenuator for a hydraulic fluid pipe, item comprising this attenuator, pipe comprising this item and method of assembly |
| CN201184476Y (en) * | 2008-01-18 | 2009-01-21 | 蔡忠 | Pipeline silencer |
| CN202117734U (en) * | 2011-06-24 | 2012-01-18 | 北京华旭佳音环保科技有限责任公司 | Impedance compound muffler with large wind volume |
| CN202228438U (en) * | 2011-09-09 | 2012-05-23 | 上海中驰建筑工程有限公司 | Compact sound absorption and noise reduction device of engine room ventilator of fishing boat |
| CN202991660U (en) * | 2012-10-29 | 2013-06-12 | 安徽宏发节能设备有限公司 | Silencing barrel |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107702266A (en) * | 2017-11-02 | 2018-02-16 | 苏州纽塔克环境科技有限公司 | A kind of split type VMC of internal-external machine and installation method |
| CN109579895A (en) * | 2018-10-22 | 2019-04-05 | 山东省科学院海洋仪器仪表研究所 | A kind of bionical pod of blade combined type |
| WO2022127818A1 (en) * | 2020-12-18 | 2022-06-23 | 香港大学浙江科学技术研究院 | Extractor hood |
| CN113107932A (en) * | 2021-03-29 | 2021-07-13 | 株洲时代新材料科技股份有限公司 | Flow guide noise reduction sheet and flow guide noise reduction method of bent pipeline |
| CN113107932B (en) * | 2021-03-29 | 2022-08-26 | 株洲时代新材料科技股份有限公司 | Flow guide noise reduction sheet and flow guide noise reduction method of bent pipeline |
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Application publication date: 20150506 |
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