CN105526197B - A kind of noise reduction of centrifugal blower, oil-filtering apparatus - Google Patents

A kind of noise reduction of centrifugal blower, oil-filtering apparatus Download PDF

Info

Publication number
CN105526197B
CN105526197B CN201510991010.0A CN201510991010A CN105526197B CN 105526197 B CN105526197 B CN 105526197B CN 201510991010 A CN201510991010 A CN 201510991010A CN 105526197 B CN105526197 B CN 105526197B
Authority
CN
China
Prior art keywords
cylinder body
outer cylinder
inner barrel
oil
centrifugal blower
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.)
Active
Application number
CN201510991010.0A
Other languages
Chinese (zh)
Other versions
CN105526197A (en
Inventor
叶丰
何立博
宁国立
李志峰
茅忠群
诸永定
申志贤
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ningbo Fotile Kitchen Ware Co Ltd
Original Assignee
Ningbo Fotile Kitchen Ware Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Ningbo Fotile Kitchen Ware Co Ltd filed Critical Ningbo Fotile Kitchen Ware Co Ltd
Priority to CN201510991010.0A priority Critical patent/CN105526197B/en
Publication of CN105526197A publication Critical patent/CN105526197A/en
Application granted granted Critical
Publication of CN105526197B publication Critical patent/CN105526197B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04DNON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00Details, component parts, or accessories
    • F04D29/66Combating cavitation, whirls, noise, vibration or the like; Balancing
    • F04D29/661Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps
    • F04D29/667Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps by influencing the flow pattern, e.g. suppression of turbulence
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04DNON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00Details, component parts, or accessories
    • F04D29/40Casings; Connections of working fluid
    • F04D29/42Casings; Connections of working fluid for radial or helico-centrifugal pumps
    • F04D29/4206Casings; Connections of working fluid for radial or helico-centrifugal pumps especially adapted for elastic fluid pumps
    • F04D29/4226Fan casings
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04DNON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00Details, component parts, or accessories
    • F04D29/70Suction grids; Strainers; Dust separation; Cleaning
    • F04D29/701Suction grids; Strainers; Dust separation; Cleaning especially adapted for elastic fluid pumps
    • F04D29/703Suction grids; Strainers; Dust separation; Cleaning especially adapted for elastic fluid pumps specially for fans, e.g. fan guards

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
  • Filtering Of Dispersed Particles In Gases (AREA)

Abstract

A kind of noise reduction of centrifugal blower, oil-filtering apparatus, it is characterised in that:Including the outer cylinder body and inner barrel located at air inlet of centrifugal fan, outer cylinder body and inner barrel are forward extended out in spiral case antetheca, circular passage is formed between outer cylinder body and inner barrel, multiple apertures are provided with the annular wall of outer cylinder body and inner barrel so that the annular wall of outer cylinder body and inner barrel is at least locally in mesh-structured.The device is provided with aperture in the annular wall of inner barrel and outer cylinder body, and circular passage is formed between inner barrel and outer cylinder body, air inlet air-flow can be converted into small yardstick whirlpool by aperture, and consume a large amount of acoustic energy by being vibrated in circular passage, sound wave is vibrated in communication process between the ring wall surface of circular passage simultaneously consumes a large amount of acoustic energy, so as to improve erasure effect;In addition, the collision probability in aperture increase fluid between particle and hole wall, while the particle in fluid is further got rid of the wall to circular passage by centrifugal force of the fluid in bending, so as to strengthen filter effect.

Description

A kind of noise reduction of centrifugal blower, oil-filtering apparatus
Technical field
The present invention relates to a kind of centrifugal blower, more particularly, to a kind of noise reduction of centrifugal blower, oil-filtering apparatus.
Background technology
The hush pipe of existing centrifugal blower is usually that inner barrel sleeve is kept off in outer cylinder body, and in the two ends sleeve of inner barrel Inner barrel and outer cylinder body, are welded and fixed by plate by baffle plate, and the filling glass cotton between inner barrel and outer cylinder body, this structure Hush pipe function it is more single, function only as the effect of noise reduction.Also disclose in the prior art it is similar with noise-reducing structure from The Chinese utility model of heart blower fan, such as Patent No. ZL 201520234680.3 (Authorization Notice No. is the U of CN 204532914) Disclosed in patent《A kind of modified centrifugal blower》, the centrifugal blower is by using damping base, it is ensured that fan operation Shi Wending and noise is low, meanwhile, soft cylinder has been connected on its reducing cylinder, make its it is convenient be connected with gas outlet, meanwhile, its noise reduction Device is fixed by outer cylinder body together with inner barrel sleeve, simple in construction, is connected firmly, and its inner barrel is plugged with round platform Shape cylinder so that first by truncated cone-shaped cylinder noise reduction when its wind enters ventilation blower by outer end, then by inner barrel noise reduction.Although, should After follow-on centrifugal blower is by dual noise reduction, more preferable erasure effect can be obtained, but the noise-reducing structure is also only realized Erasure effect, function is more single.
The content of the invention
The technical problems to be solved by the invention are that there is provided a kind of simple in construction, energy is same for above-mentioned state of the art The noise reduction of the centrifugal blower of Shi Shixian noise reductions and oil filtering function, oil-filtering apparatus.
The present invention solve the technical scheme that is used of above-mentioned technical problem for:The noise reduction of the centrifugal blower, oil-filtering apparatus, its It is characterised by:Including the outer cylinder body and inner barrel located at air inlet of centrifugal fan, the outer cylinder body and inner barrel are forward extended out In the spiral case antetheca of centrifugal blower, circular passage is formed between the outer cylinder body and inner barrel, in outer cylinder body and inner barrel Annular wall on be provided with multiple apertures so that the annular wall of outer cylinder body and inner barrel is at least locally in mesh-structured.
Outer cylinder body can have a variety of mounting structures, it is preferable that be provided with air intake mouth circle in air inlet of centrifugal fan, described outer The rear end of cylinder is arranged in air intake mouth circle, and the barrel dliameter of outer cylinder body is adapted with air intake mouth circle.
Inner barrel can have a variety of mounting structures, it is preferable that the front end of the inner barrel is forward extended out in described outer barrel Body is simultaneously arranged on front cover plate of fan, and the rear end of the inner barrel stretches out in described outer cylinder body backward.
Outer cylinder body and inner barrel can have various structures and size relationship, it is preferable that the outer cylinder body and inner barrel are Cylinder, the diameter D of the outer cylinder body1With the diameter D of inner barrel2Between relation be:
Further preferably, the diameter D of the outer cylinder body1=150~300mm.
Further preferably, the inner barrel is forward extended out in spiral case antetheca apart from L1With the outer cylinder body forward extend out in Spiral case antetheca apart from L2Between relation be:
In order to improve noise reduction and oil filter effect, it is provided with the whole annular wall of the outer cylinder body and inner barrel described small Hole, aperture d=1.0~3.0mm of the aperture, and percent opening are 70%~90%.
In order that the oil droplet filtered through inner barrel and outer cylinder body can be collected in inner barrel and outer cylinder body, it is preferable that described Aperture be only opened in the annular wall more than outer cylinder body and inner barrel bottom, and the bottom of outer cylinder body and inner barrel is non-porous The corresponding central angle of arc length at position is 60-150 °.So, the bottom of inner barrel and outer cylinder body is equivalent to constituting oil collecting zone Part oil droplet on domain, inner barrel and outer cylinder body can be dropped into the oil-collecting region.
In order that the oil droplet filtered through inner barrel and outer cylinder body can be collected in the swab case below spiral case, described outer barrel Body and inner barrel are tilted obliquely from front to back, oil leaking hole are provided with the spiral case bottom of centrifugal blower, in the oil leaking hole Lower section is provided with swab case.
Further preferably, the front end of the swab case forms to forward extend out connects oily tongue in the outer cylinder body.So, outer barrel Part oil droplet on body and inner barrel, which is fallen into, to be connect after oily tongue again rearwards into swab case.
Compared with prior art, the advantage of the invention is that:The device is provided with the annular wall of inner barrel and outer cylinder body Circular passage is formed between aperture, and inner barrel and outer cylinder body, air inlet air-flow can be converted into small yardstick whirlpool by aperture, And a large amount of acoustic energy are consumed by being vibrated in circular passage, while sound wave vibrates communication process between the ring wall surface of circular passage In consume a large amount of acoustic energy, so as to obtain preferable erasure effect;In addition, fluid is flowing through the process of circular passage and aperture In, the collision probability in aperture increase fluid between particle and hole wall, while centrifugal force of the fluid in bending is further by fluid In particle get rid of wall to circular passage, so as to strengthen filter effect.
Brief description of the drawings
Fig. 1 is the structural representation of the embodiment of the present invention one;
Fig. 2 is the structural representation of another angle of the embodiment of the present invention one (front cover plate of fan is housed);
Fig. 3 is the structure sectional view of the embodiment of the present invention one;
Fig. 4 is the structural representation of the embodiment of the present invention two.
Embodiment
The present invention is described in further detail below in conjunction with accompanying drawing embodiment.
Embodiment one:
As shown in Figure 1 to Figure 3, the noise reduction of the centrifugal blower in the present embodiment, oil-filtering apparatus include being located at air inlet Outer cylinder body 1 and inner barrel 2, outer cylinder body 1 and inner barrel 2 forward extended out in spiral case antetheca 6, outer cylinder body 1 and inner barrel 2 it Between be formed with circular passage 3, be full of aperture 4 in the whole annular wall of outer cylinder body and inner barrel so that outer cylinder body and inner barrel Whole annular wall in mesh-structured.
In the present embodiment, the air intake mouth circle 5 of circle is installed in air inlet, correspondingly, outer cylinder body 1 is cylinder and big Small to be adapted with air intake mouth circle 5, the rear end of outer cylinder body 1 can be fixed by welding in air intake mouth circle 5.Inner barrel 2 is also circle Cylinder, the front end of inner barrel 2 forward extends out in outer cylinder body 1 and is fixed on front cover plate of fan 7, also, inner barrel 2 rear end backward Stretch out in outer cylinder body 1, i.e. inner barrel 2 and extend rearward into blower interior.
Position relationship between before and after outer cylinder body 1 and inner barrel 2 is:If inner barrel 2 forward extend out in spiral case antetheca 6 away from From for L1, in the present embodiment, L1As the distance between spiral case antetheca 6 of blower fan and front cover plate of fan 7, if outer cylinder body 1 is to extension Distance for spiral case antetheca 6 is L2, then L1With L2Between relation be:
In the present embodiment, outer cylinder body 1 and inner barrel 2 are cylinder, if a diameter of D of outer cylinder body 11, the diameter of inner barrel 2 For D2, then D1With D2Between relation be:For different centrifugal blowers, D1And D2Numerical value respectively have not Together, the diameter D of outer cylinder body 11Determined by the diameter of air intake mouth circle 5, it is conventional because the size of cooking-fume exhauster blower impeller is limited Ground, the diameter D of outer cylinder body 11=150~300mm.In addition, in order to obtain optimal noise reduction and oil filter effect, the aperture d of aperture 4 =1.0~3.0mm, percent opening is 70%~90%.
In the present embodiment, outer cylinder body 1 and inner barrel 2 are horizontally disposed with from front to back, i.e., in outer cylinder body 1 and inner barrel 2 Diameter parallel is in the air intake direction of air inlet.In addition, for the ease of oil-collecting, outer cylinder body 1 and inner barrel 2 can also from front to back Tilt obliquely.Oil leaking hole 8 is provided with the spiral case bottom of centrifugal blower, swab case 9 is provided with the lower section of oil leaking hole 8, also, connect The front end of oil box 9 forms to forward extend out connects oily tongue 91 in outer cylinder body 1.During blower fan work, filtered through outer cylinder body 1 and inner barrel 2 Most of oil droplet drop onto backward inside the spiral case of blower fan, and by oil leaking hole 8 flow into swab case 9 in, small part oil droplet is straight It is connected on outside blower fan to drop onto and connects on oily tongue 91, and and then rearwards into swab case 9.
The noise reduction, filter noise reduction principle it is as follows:
1), air-flow is converted into small yardstick whirlpool by aperture, and a large amount of acoustic energy are consumed by being vibrated in annular chamber;
2), sound wave vibrates between ring wall surface consumes a large amount of acoustic energy in communication process.
The noise reduction, filter through-flow and work principle of filter it is as follows:
1), the collision probability in aperture increase fluid between particle and hole wall;
2), while centrifugal force of the fluid in bending further gets rid of the particle in fluid to wall, filter effect is strengthened.
Embodiment two:
As shown in figure 4, in the present embodiment, aperture 4 is only opened in annular wall more than outer cylinder body 1 and the bottom of inner barrel 2, So that the part of the annular wall of outer cylinder body 1 and inner barrel 2 is in mesh-structured, and the non-porous position in bottom of outer cylinder body 1 and inner barrel 2 The corresponding central angle of arc length be 60-150 °.So, oil-collecting region 10 can be formed on the bottom of outer cylinder body 1 and inner barrel 2, outside Part oil droplet on cylinder 1 and the ring wall of inner barrel 2 can be dropped onto in the oil-collecting region 10.
It the foregoing is only the preferred embodiment of the present invention, it is noted that for those of ordinary skills, Under the premise of the principle of the present invention is not departed from, a variety of remodeling or improvement can be carried out to the present invention, these are regarded as the present invention Protection domain within.

Claims (10)

1. a kind of noise reduction of centrifugal blower, oil-filtering apparatus, it is characterised in that:Including the outer cylinder body located at air inlet of centrifugal fan (1) and inner barrel (2), the outer cylinder body (1) and inner barrel (2) forward extend out the spiral case antetheca (6) in centrifugal blower, in institute State and circular passage (3) is formed between outer cylinder body (1) and inner barrel (2), in the annular of the outer cylinder body (1) and inner barrel (2) Multiple apertures (4) are provided with wall so that the annular wall of outer cylinder body (1) and inner barrel (2) is at least locally in mesh-structured.
2. the noise reduction of centrifugal blower according to claim 1, oil-filtering apparatus, it is characterised in that:In air inlet of centrifugal fan Air intake mouth circle (5) is installed, the rear end of the outer cylinder body (1) is arranged in air intake mouth circle (5), and the barrel dliameter of outer cylinder body (1) with Air intake mouth circle (5) is adapted.
3. the noise reduction of centrifugal blower according to claim 1, oil-filtering apparatus, it is characterised in that:Before the inner barrel (2) End is forward extended out in described outer cylinder body (1) and on front cover plate of fan (7), and the rear end of the inner barrel (2) is stretched backward For described outer cylinder body (1).
4. the noise reduction of centrifugal blower according to claim 1, oil-filtering apparatus, it is characterised in that:The outer cylinder body (1) and interior Cylinder (2) is cylinder, the diameter D of the outer cylinder body (1)1With the diameter D of inner barrel (2)2Between relation be:
<mrow> <mfrac> <mn>1</mn> <mn>3</mn> </mfrac> <msub> <mi>D</mi> <mn>1</mn> </msub> <mo>&amp;le;</mo> <msub> <mi>D</mi> <mn>2</mn> </msub> <mo>&amp;le;</mo> <mfrac> <mn>2</mn> <mn>3</mn> </mfrac> <msub> <mi>D</mi> <mn>1</mn> </msub> <mo>.</mo> </mrow>
5. the noise reduction of centrifugal blower according to claim 4, oil-filtering apparatus, it is characterised in that:The outer cylinder body (1) it is straight Footpath D1=150~300mm.
6. the noise reduction of centrifugal blower according to claim 1, oil-filtering apparatus, it is characterised in that:The inner barrel (2) is forward Stretch out in being forward extended out apart from L1 and the outer cylinder body (1) in the pass between L2 of spiral case antetheca (6) for spiral case antetheca (6) It is to be: <mrow> <mfrac> <mn>1</mn> <mn>3</mn> </mfrac> <msub> <mi>L</mi> <mn>1</mn> </msub> <mo>&amp;le;</mo> <msub> <mi>L</mi> <mn>2</mn> </msub> <mo>&amp;le;</mo> <mfrac> <mn>2</mn> <mn>3</mn> </mfrac> <msub> <mi>L</mi> <mn>1</mn> </msub> <mo>.</mo> </mrow>
7. the noise reduction of centrifugal blower according to claim 1, oil-filtering apparatus, it is characterised in that:In the outer cylinder body (1) and The whole annular wall of inner barrel (2) is provided with described aperture (4), aperture d=1.0~3.0mm of the aperture (4), and opens Porosity is 70%~90%.
8. the noise reduction of centrifugal blower according to claim 1, oil-filtering apparatus, it is characterised in that:Described aperture (4) is only opened Be located in the annular wall more than outer cylinder body (1) and inner barrel (2) bottom, and outer cylinder body (1) and inner barrel (2) bottom without The corresponding central angle of arc length of hole portion position is 60-150 °.
9. the noise reduction of the centrifugal blower according to any claim in claim 1 to 8, oil-filtering apparatus, it is characterised in that: Described outer cylinder body (1) and inner barrel (2) is tilted obliquely from front to back, and oil leaking hole is provided with the spiral case bottom of centrifugal blower (8), it is provided with swab case (9) in the lower section of the oil leaking hole (8).
10. the noise reduction of centrifugal blower according to claim 9, oil-filtering apparatus, it is characterised in that:The swab case (9) Front end forms to forward extend out connects oily tongue (91) in the outer cylinder body (1).
CN201510991010.0A 2015-12-24 2015-12-24 A kind of noise reduction of centrifugal blower, oil-filtering apparatus Active CN105526197B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201510991010.0A CN105526197B (en) 2015-12-24 2015-12-24 A kind of noise reduction of centrifugal blower, oil-filtering apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201510991010.0A CN105526197B (en) 2015-12-24 2015-12-24 A kind of noise reduction of centrifugal blower, oil-filtering apparatus

Publications (2)

Publication Number Publication Date
CN105526197A CN105526197A (en) 2016-04-27
CN105526197B true CN105526197B (en) 2017-10-27

Family

ID=55768625

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201510991010.0A Active CN105526197B (en) 2015-12-24 2015-12-24 A kind of noise reduction of centrifugal blower, oil-filtering apparatus

Country Status (1)

Country Link
CN (1) CN105526197B (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106640763B (en) * 2016-10-20 2022-11-25 宁波方太厨具有限公司 Air inlet ring and centrifugal fan adopting same
CN106881011A (en) * 2017-01-18 2017-06-23 合肥杰通环境技术有限公司 A kind of compound smoke hood type lampblack purifying system

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101535656A (en) * 2006-11-02 2009-09-16 松下电器产业株式会社 Centrifugal fan
CN101714353A (en) * 2008-10-01 2010-05-26 通用电气公司 Sound attenuation systems
CN102518605A (en) * 2005-02-23 2012-06-27 康明斯涡轮增压技术有限公司 Compressor
JP3191383U (en) * 2014-04-09 2014-06-19 陳玉沛 Sound absorber for fan
CN104180412A (en) * 2014-08-09 2014-12-03 华帝股份有限公司 Smoke absorbing and noise reducing device of range hood
CN204532984U (en) * 2015-04-17 2015-08-05 浙江风神风机制造有限公司 A kind of centrifugal fan baffler
CN104963899A (en) * 2015-07-14 2015-10-07 柳州职业技术学院 Silencer of draught fan
CN104990239A (en) * 2015-05-20 2015-10-21 西安建筑科技大学 Annular uniform cross-section flow equalizing apparatus for cylinder wall-attached air supply
CN205260437U (en) * 2015-12-24 2016-05-25 宁波方太厨具有限公司 Centrifugal fan's amortization, oil filter device

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102518605A (en) * 2005-02-23 2012-06-27 康明斯涡轮增压技术有限公司 Compressor
CN101535656A (en) * 2006-11-02 2009-09-16 松下电器产业株式会社 Centrifugal fan
CN101714353A (en) * 2008-10-01 2010-05-26 通用电气公司 Sound attenuation systems
JP3191383U (en) * 2014-04-09 2014-06-19 陳玉沛 Sound absorber for fan
CN104180412A (en) * 2014-08-09 2014-12-03 华帝股份有限公司 Smoke absorbing and noise reducing device of range hood
CN204532984U (en) * 2015-04-17 2015-08-05 浙江风神风机制造有限公司 A kind of centrifugal fan baffler
CN104990239A (en) * 2015-05-20 2015-10-21 西安建筑科技大学 Annular uniform cross-section flow equalizing apparatus for cylinder wall-attached air supply
CN104963899A (en) * 2015-07-14 2015-10-07 柳州职业技术学院 Silencer of draught fan
CN205260437U (en) * 2015-12-24 2016-05-25 宁波方太厨具有限公司 Centrifugal fan's amortization, oil filter device

Also Published As

Publication number Publication date
CN105526197A (en) 2016-04-27

Similar Documents

Publication Publication Date Title
CN203628774U (en) Cyclone used for separating oil smoke of range hood
CN105526197B (en) A kind of noise reduction of centrifugal blower, oil-filtering apparatus
CN205330774U (en) Special type exhaust of vehicle silencer
CN203628771U (en) Cyclone used for separating oil smoke of range hood
CN203628775U (en) Cyclone used for separating oil smoke of range hood
CN106640763A (en) Air inlet ring and centrifugal fan comprising same
CN209293884U (en) A kind of motorcycle noise reducing device
CN204522644U (en) Rotating centrifugal sack cleaner
CN103982469B (en) A kind of for the denoising draught fan spiral case in smoke exhaust ventilator
CN207278474U (en) A kind of air compressor with decrease of noise functions
CN206207517U (en) A kind of noise reduction impeller and application have the range hood of the impeller
CN205963943U (en) Dust catcher with amortization mechanism
CN205995419U (en) In order to clear up the device for high-efficiency cleaning of the tubular body catalyst of reactor
CN209116413U (en) A kind of integrated kitchen range bellow guiding device and integrated kitchen range
CN205260437U (en) Centrifugal fan&#39;s amortization, oil filter device
CN207722512U (en) A kind of environment protection-type gas-filtering device
CN205895706U (en) Range hood&#39;s silencer
CN206073185U (en) Side-suction type range hood denoising device
CN210599490U (en) Dust, paint mist and oil smoke waste gas purification exhaust fan
CN203628770U (en) Cyclone used for separating oil smoke of range hood
CN203476442U (en) Horizontally-mounted silencer
CN207855631U (en) A kind of dust catcher with multistage denoising structure
CN206793293U (en) A kind of air cleaning unit
CN106246604A (en) A kind of low noise cooker hood
CN205744145U (en) A kind of low noise diesel engine

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant