CN104863681A - Exhaust pipe silencing method - Google Patents
Exhaust pipe silencing method Download PDFInfo
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- CN104863681A CN104863681A CN201510171658.3A CN201510171658A CN104863681A CN 104863681 A CN104863681 A CN 104863681A CN 201510171658 A CN201510171658 A CN 201510171658A CN 104863681 A CN104863681 A CN 104863681A
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Abstract
The invention discloses an exhaust pipe silencing method. According to the exhaust pipe silencing method, two-stage silencing is performed in a cylinder body, so that when a relatively small amount of airflow enters from an air inlet, corresponding noise generated by the airflow is relatively low, a pneumatic control valve is directly closed, the airflow is directly discharged from an air pipe through an air outlet, the possibility of an airflow residue in a silencing cavity is lowered, and the service life of a silencer is prolonged.
Description
Technical field
The present invention relates to a kind of baffler, specifically refer to a kind of noise reduction processing method of outlet pipe.
Background technique
In urban environment, traffic noise is the pollution sources that radiation is the strongest, impact is the widest.In motor vehicle noise, exhaust sound is one of main noise sound source, and its reduction, mainly by installing exhaust silencer, must produce a very large impact motor after fixing a silencer; The power loss of general silencing apparatus, 3% ~ 8%, allows larger power loss when sound deadening capacity is larger; The silencing apparatus of coupling low-powered engine more requires lower power loss.
The car owning amount of China is increasing, and people are no longer only the traffic tool to the requirement of automobile, more require the energy-conserving and environment-protective of car, attractive in appearance and comfortable.The traffic noise of motor vehicle is main sources of urban road noise, and the legislations for noise for automobile will be constantly strict.But when general baffler production and processing, the dissipative muffler of main application on the market at present and reactive muffler, can only process the noise of high frequency or medium and low frequency individually, Applicable scope is wideless, and with regard to dissipative muffler: at high temperature, water vapour and have in the gas of corrosive action to sound-absorbing material, the working life of silencing apparatus is short, to low-frequency noise weak effect; It is excessive that maximum drawback is exactly silencing apparatus power loss.
Summary of the invention
The object of the present invention is to provide a kind of noise reduction processing method of outlet pipe, reduce air-flow to the infringement of baffler, reduce the loss power of silencing apparatus.
Object of the present invention is achieved through the following technical solutions:
A noise reduction processing method for outlet pipe, comprises the following steps:
(A) be passed in breathing pipe by the air-flow of discharge by suction port, pneumatic control valve can control the flow direction of air-flow according to the size of throughput;
(B) when throughput exceedes certain limit, pneumatic control valve is opened, air-flow directly enters in the space that first demarcation strip and silencing cavity wall form by suction port, most air-flow enters into second space between demarcation strip and baffle plate by connecting tube, and the air-flow of remainder carries out noise reduction process to it step by step by the through hole on two demarcation strips;
(C) air-flow passed into by suction port enters in larger space environment suddenly in less space environment, the sound wave of the minority frequency near through hole natural frequency is only had just to arrive second space between demarcation strip and baffle plate by through hole, the sound wave of minority frequency is not then by through hole in addition, the space that jointly can only form at demarcation strip and silencing cavity end is constantly reflected, until air-flow momentum disappears, namely complete the noise reduction operation of first stage;
(D) after the noise reduction operation of first stage, entered in the connecting tube between two baffle plates by the air-flow major part significantly weakened, finally discharged by air outlet;
(E) sound wave of the minority frequency of remainder near pore natural frequency just arrives air outlet by pore, the sound wave of minority frequency is not then by pore in addition, the space that jointly can only form at second baffle plate and silencing cavity the other end end is constantly reflected, until air-flow momentum disappears, namely complete the noise reduction operation of second stage;
In above-mentioned steps, silencing cavity is provided with in described cylindrical shell, the two ends of cylindrical shell are respectively arranged with suction port and air outlet, in described silencing cavity, along direction, air outlet, two demarcation strips and baffle plate are installed successively, connecting tube runs through the top of two demarcation strips, connecting tube runs through the bottom of two baffle plates, the bottom of demarcation strip is provided with multiple through hole, the top of baffle plate is provided with multiple pore, also breathing pipe is connected with between described air outlet and suction port, described breathing pipe runs through demarcation strip and baffle plate, and breathing pipe and suction port joint are provided with pneumatic control valve.
Traditional silencing apparatus in use, regardless of throughput size, air-flow all can pass to carry out noise reduction process in baffler internal structure, and a small amount of impurity be blended in air-flow or corrosive deposit can rest on baffler inside for a long time, certain damage can be caused to its internal structure, reduce the power of baffler; The part of the air-flow residue minute quantity through silencing cavity in the present invention remains in silencing cavity, reduces residual fraction air-flow to the impact of baffler inside or corrosion, reduces the loss power of silencing apparatus; And when the throughput flowed into by suction port is less, the noise of the corresponding generation of air-flow is less, and pneumatic control valve directly cuts out, and air-flow directly has breathing pipe to discharge through air outlet, reduce the possibility that in silencing cavity, air-flow is residual, be conducive to the working life of improving baffler.
The diameter of described pore is successively decreased along direction, air outlet.Second stage noise reduction operation is the final process to noise sound wave in air-flow, aperture on second baffle plate to suction port to direction, air outlet is less than the aperture of first baffle plate, air-flow is made to be graded process again, through twice screening of second stage noise reduction operation, thoroughly can ensure that the noise in air-flow is completely eliminated.
Diameter away from the pore on the baffle plate of air outlet is greater than the diameter of the pore on the baffle plate of air outlet.Through hole mainly plays the effect of the noise sound wave of screening through hole natural frequency in first stage noise reduction operation, pore is then the effect of the noise sound wave playing screening pore natural frequency in second stage noise reduction operation, after first stage noise reduction operation terminates, enter into the air-flow of second stage noise reduction operation when air passing hole, the frequency spectrum of noise will shift to high frequency or ultra-high frequency, audible sound composition in frequency spectrum is obviously reduced, thus the interference reduced people and injury; The aperture of through hole is greater than the aperture of pore, and both self intrinsic frequencies are different, and can successively eliminate the sound wave of different frequency, after ensureing airflow passes the present invention, peace and quiet are harmlessly discharged.
The connecting tube mouth of pipe between described demarcation strip is just to pore position.Air-flow major part through first stage noise reduction operation to be passed in the spatial joint clearance between the second demarcation strip and first baffle plate by the connecting tube mouth of pipe, the connecting tube mouth of pipe is just to the position of pore, the air-flow flowing fast through connecting tube is directly screened by pore, and the connecting tube that remaining air-flow is connected by baffle plate bottom is again discharged, increase the efficiency of pore screening sound wave.
Also comprise the silencing cotton being arranged at cylinder inboard wall.After the noise in air-flow is completely by first stage and second stage noise reduction operation, the sound wave of low and medium frequency is thoroughly processed, remaining high frequency sound wave is absorbed by the numerous spaces on silencing cotton, after constantly transmitting with absorption, ensures that in air-flow, noise is eliminated completely.
The present invention compared with prior art, has following advantage and beneficial effect:
1, the noise reduction processing method of a kind of outlet pipe of the present invention, when the throughput flowed into by suction port is less, the noise of the corresponding generation of air-flow is less, pneumatic control valve directly cuts out, air-flow directly has breathing pipe to discharge through air outlet, reduce the possibility that in silencing cavity, air-flow is residual, be conducive to the working life of improving baffler;
2, the noise reduction processing method of a kind of outlet pipe of the present invention, second stage noise reduction operation is the final process to noise sound wave in air-flow, aperture on second baffle plate to suction port to direction, air outlet is less than the aperture of first baffle plate, air-flow is made to be graded process again, through twice screening of second stage noise reduction operation, thoroughly can ensure that the noise in air-flow is completely eliminated.
3, the noise reduction processing method of a kind of outlet pipe of the present invention, after the noise in air-flow is completely by first stage and second stage noise reduction operation, the sound wave of low and medium frequency is thoroughly processed, remaining high frequency sound wave is absorbed by the numerous spaces on silencing cotton, after constantly transmitting with absorption, ensure that in air-flow, noise is eliminated completely.
Accompanying drawing explanation
Accompanying drawing described herein is used to provide the further understanding to the embodiment of the present invention, forms a application's part, does not form the restriction to the embodiment of the present invention.In the accompanying drawings:
Fig. 1 is structural representation of the present invention;
Mark and corresponding component title in accompanying drawing:
1-cylindrical shell, 2-silencing cavity, 3-suction port, 4-air outlet, 5-demarcation strip, 6-baffle plate, 7-connecting tube, 8-through hole, 9-pore, 10-breathing pipe, 11-pneumatic control valve, 12-silencing cotton.
Embodiment
Clearly understand for making the object, technical solutions and advantages of the present invention, below in conjunction with embodiment and accompanying drawing, the present invention is described in further detail, and exemplary embodiment of the present invention and explanation thereof are only for explaining the present invention, not as a limitation of the invention.
Embodiment 1
As shown in Figure 1, the present embodiment, comprises the following steps:
(A) be passed in breathing pipe by the air-flow of discharge by suction port, pneumatic control valve can control the flow direction of air-flow according to the size of throughput;
(B) when throughput exceedes certain limit, pneumatic control valve is opened, air-flow directly enters in the space that first demarcation strip and silencing cavity wall form by suction port, most air-flow enters into second space between demarcation strip and baffle plate by connecting tube, and the air-flow of remainder carries out noise reduction process to it step by step by the through hole on two demarcation strips;
(C) air-flow passed into by suction port enters in larger space environment suddenly in less space environment, the sound wave of the minority frequency near through hole natural frequency is only had just to arrive second space between demarcation strip and baffle plate by through hole, the sound wave of minority frequency is not then by through hole in addition, the space that jointly can only form at demarcation strip and silencing cavity end is constantly reflected, until air-flow momentum disappears, namely complete the noise reduction operation of first stage;
(D) after the noise reduction operation of first stage, entered in the connecting tube between two baffle plates by the air-flow major part significantly weakened, finally discharged by air outlet;
(E) sound wave of the minority frequency of remainder near pore natural frequency just arrives air outlet by pore, the sound wave of minority frequency is not then by pore in addition, the space that jointly can only form at second baffle plate and silencing cavity the other end end is constantly reflected, until air-flow momentum disappears, namely complete the noise reduction operation of second stage;
In above-mentioned steps, silencing cavity 2 is provided with in described cylindrical shell 1, the two ends of cylindrical shell 1 are respectively arranged with suction port 3 and air outlet 4, in described silencing cavity 2, along direction, air outlet 4, two demarcation strips 5 and baffle plate 6 are installed successively, connecting tube 7 runs through the top of two demarcation strips 5, connecting tube 7 runs through the bottom of two baffle plates 6, the bottom of demarcation strip 5 is provided with multiple through hole 8, the top of baffle plate 6 is provided with multiple pore 9, breathing pipe 10 is also connected with between described air outlet 4 and suction port 3, described breathing pipe 10 runs through demarcation strip 5 and baffle plate 6, breathing pipe 10 and suction port 3 joint are provided with pneumatic control valve 11, the aperture of described through hole 8 is greater than the diameter of pore 9, connecting tube 7 mouth of pipe between described demarcation strip 5 is just to pore 9 position, and the diameter away from the pore 9 on the baffle plate 6 of air outlet 4 is greater than the diameter of the pore 9 on the baffle plate 6 of air outlet 4, also comprise the silencing cotton 12 being arranged at cylindrical shell 1 inwall.
When the present invention uses, air-flow is passed in breathing pipe 10 by suction port 3, the pneumatic control valve 11 being arranged on suction port 3 place can control the flow direction of air-flow according to the size of throughput, when throughput exceedes certain limit, pneumatic control valve 11 is opened, air-flow is made directly to enter in the space that first demarcation strip 5 and silencing cavity 2 wall form by suction port 3, most air-flow enters into the space between second demarcation strip 5 and baffle plate 6 by connecting tube 7, the air-flow of remainder carries out noise reduction process to it step by step by the through hole 8 on two demarcation strips 5, the air-flow passed into by suction port 3 enters in larger space environment suddenly in less space environment, the sound wave of the minority frequency near through hole 8 natural frequency is only had just to arrive the space between second demarcation strip 5 and baffle plate 6 by through hole 8, the sound wave of minority frequency is not then by through hole 8 in addition, the space that jointly can only form in demarcation strip 5 and silencing cavity 2 end is constantly reflected, until air-flow momentum disappears, namely the noise reduction operation of first stage is completed,
After the noise reduction operation of first stage, the overall momentum of air-flow has been consumed major part, continue the noise reduction operation starting second stage, and the noise reduction mode of first stage and the noise reduction mode of second stage similar, entered in the connecting tube 7 between two baffle plates 6 by the air-flow major part significantly weakened, finally discharged by air outlet 4, the sound wave of the minority frequency of remainder near pore 9 natural frequency just arrives air outlet 4 by pore 9, the sound wave of minority frequency is not then by pore 9 in addition, the space that jointly can only form in second baffle plate 6 and silencing cavity 2 the other end end is constantly reflected, until air-flow momentum disappears, namely the noise reduction operation of second stage is completed, finally reach good noise reduction object, and remain in silencing cavity 2 through the part of the air-flow residue minute quantity of silencing cavity 2 fast, reduce residual fraction air-flow to the impact of baffler inside or corrosion, reduce the loss power of silencing apparatus, and when the throughput flowed into by suction port 3 is less, the noise of the corresponding generation of air-flow is less, pneumatic control valve 11 directly cuts out, and air-flow directly has breathing pipe 10 to discharge through air outlet 4.
Through hole 8 mainly plays the effect of the noise sound wave of screening through hole 8 natural frequency in first stage noise reduction operation, pore 9 is then the effect of the noise sound wave playing screening pore 9 natural frequency in second stage noise reduction operation, after first stage noise reduction operation terminates, enter into the air-flow of second stage noise reduction operation when air passing hole 9, the frequency spectrum of noise will shift to high frequency or ultra-high frequency, audible sound composition in frequency spectrum is obviously reduced, thus the interference reduced people and injury; The aperture of through hole 8 is greater than the aperture of pore 9, and both self intrinsic frequencies are different, and can successively eliminate the sound wave of different frequency, after ensureing airflow passes the present invention, peace and quiet are harmlessly discharged; Air-flow major part through first stage noise reduction operation to be passed in the spatial joint clearance between the second demarcation strip 5 and first baffle plate 6 by connecting tube 7 mouth of pipe, connecting tube 7 mouth of pipe is just to the position of pore 9, the air-flow flowing fast through connecting tube 7 is directly screened by pore 9, and the connecting tube 7 that remaining air-flow is connected by baffle plate 6 bottom is again discharged, increase the efficiency that pore 9 screens sound wave; Second stage noise reduction operation is the final process to noise sound wave in air-flow, be less than the aperture of first baffle plate 6 to the aperture on second baffle plate 6 in direction, air outlet 4 to suction port 3, air-flow is made to be graded process again, through twice screening of second stage noise reduction operation, thoroughly can ensure that the noise in air-flow is completely eliminated.
After the noise in air-flow is completely by first stage and second stage noise reduction operation, the sound wave of low and medium frequency is thoroughly processed, remaining high frequency sound wave is absorbed by the numerous spaces on silencing cotton 12, after constantly transmitting with absorption, ensures that in air-flow, noise is eliminated completely.
Above-described embodiment; object of the present invention, technological scheme and beneficial effect are further described; be understood that; the foregoing is only the specific embodiment of the present invention; the protection domain be not intended to limit the present invention; within the spirit and principles in the present invention all, any amendment made, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (5)
1. a noise reduction processing method for outlet pipe, is characterized in that: comprise the following steps:
(A) be passed in breathing pipe (10) by the air-flow of discharge by inlet charge mouth (3), pneumatic control valve (11) can control the flow direction of air-flow according to the size of throughput;
(B) when throughput exceedes certain limit, pneumatic control valve (11) door is opened, air-flow directly enters in the space that first demarcation strip (5) and silencing cavity (2) wall form by suction port (3), most air-flow enters into the space between second demarcation strip (5) and baffle plate (6) by connecting tube, and the air-flow of remainder carries out noise reduction process to it step by step by the through hole (8) on two demarcation strips (5);
(C) air-flow passed into by suction port (3) enters in larger space environment suddenly in less space environment, the sound wave of the minority frequency near through hole (8) natural frequency is only had just to arrive the space between second demarcation strip (5) and baffle plate (6) by through hole (8), the sound wave of minority frequency is not then by through hole (8) in addition, the space that jointly can only form in demarcation strip (5) and silencing cavity (2) end is constantly reflected, until air-flow momentum disappears, namely complete the noise reduction operation of first stage;
(D) after the noise reduction operation of first stage, entered in the connecting tube (7) between two baffle plates (6) by the air-flow major part significantly weakened, finally discharged by air outlet (4);
(E) sound wave of the minority frequency of remainder near pore (9) natural frequency just arrives air outlet (4) by pore (9), the sound wave of minority frequency is not then by pore (4) in addition, the space that jointly can only form in second baffle plate (6) and silencing cavity (2) the other end end is constantly reflected, until air-flow momentum disappears, namely complete the noise reduction operation of second stage;
In above-mentioned steps, silencing cavity (2) is provided with in described cylindrical shell (1), the two ends of cylindrical shell (1) are respectively arranged with suction port (3) and air outlet (4), in described silencing cavity (2), along air outlet (4) direction, two demarcation strips (5) and baffle plate (6) are installed successively, connecting tube (7) runs through the top of two demarcation strips (5), connecting tube (7) runs through the bottom of two baffle plates (6), the bottom of demarcation strip (5) is provided with multiple through hole (8), the top of baffle plate (6) is provided with multiple pore (9), breathing pipe (10) is also connected with between described air outlet (4) and suction port (3), described breathing pipe (10) runs through demarcation strip (5) and baffle plate (6), breathing pipe (10) and suction port (3) joint are provided with pneumatic control valve (11).
2. the noise reduction processing method of a kind of outlet pipe according to claim 1, is characterized in that: the diameter of described pore (9) is successively decreased along direction, air outlet.
3. the noise reduction processing method of a kind of outlet pipe according to claim 1, is characterized in that: connecting tube (7) mouth of pipe between described demarcation strip (5) is just to pore (9) position.
4. the noise reduction processing method of a kind of outlet pipe according to claim 2, is characterized in that: the diameter away from the pore (9) on the baffle plate (6) of air outlet (4) is greater than the diameter of the pore (9) on the baffle plate (6) of air outlet (4).
5. the noise reduction processing method of a kind of outlet pipe according to claim 1 ~ 4 any one, is characterized in that: also comprise the silencing cotton (12) being arranged at cylindrical shell (1) inwall.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510171658.3A CN104863681A (en) | 2015-04-13 | 2015-04-13 | Exhaust pipe silencing method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510171658.3A CN104863681A (en) | 2015-04-13 | 2015-04-13 | Exhaust pipe silencing method |
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| CN104863681A true CN104863681A (en) | 2015-08-26 |
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| CN201510171658.3A Pending CN104863681A (en) | 2015-04-13 | 2015-04-13 | Exhaust pipe silencing method |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105545412A (en) * | 2016-02-23 | 2016-05-04 | 偃师市宇龙金属加工厂 | Exhaust silencer for internal combustion engine |
| CN105545413A (en) * | 2016-02-23 | 2016-05-04 | 偃师市宇龙金属加工厂 | Multi-air-chamber exhaust silencer for internal combustion engine |
| CN105673138A (en) * | 2016-02-23 | 2016-06-15 | 偃师市宇龙金属加工厂 | Multi-gas-chamber cyclone silencing method of internal combustion engine |
| CN106683657A (en) * | 2016-11-30 | 2017-05-17 | 湖州益环环保工程有限公司 | Efficient silencer capable of changing exhaust position |
| CN115653710A (en) * | 2022-12-29 | 2023-01-31 | 中国石油大学(华东) | Airflow silencer for engine and working method |
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| US20040216951A1 (en) * | 2003-05-01 | 2004-11-04 | Chao Cai | High performance muffler |
| US7337876B2 (en) * | 2000-07-14 | 2008-03-04 | Nilfisk-Advance A/S | Suction apparatus with noise reduction means |
| CN203742738U (en) * | 2014-03-18 | 2014-07-30 | 成都陵川常友汽车部件制造有限公司 | Noise treatment device for exhaust pipe |
| CN104121069A (en) * | 2014-07-28 | 2014-10-29 | 成都兴博达精密机械有限公司 | Automobile exhaust pipe noise elimination processing method |
| CN104165083A (en) * | 2014-03-18 | 2014-11-26 | 成都陵川常友汽车部件制造有限公司 | Noise reduction device of exhaust pipe |
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2015
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| US7337876B2 (en) * | 2000-07-14 | 2008-03-04 | Nilfisk-Advance A/S | Suction apparatus with noise reduction means |
| US20040216951A1 (en) * | 2003-05-01 | 2004-11-04 | Chao Cai | High performance muffler |
| CN203742738U (en) * | 2014-03-18 | 2014-07-30 | 成都陵川常友汽车部件制造有限公司 | Noise treatment device for exhaust pipe |
| CN104165083A (en) * | 2014-03-18 | 2014-11-26 | 成都陵川常友汽车部件制造有限公司 | Noise reduction device of exhaust pipe |
| CN104121069A (en) * | 2014-07-28 | 2014-10-29 | 成都兴博达精密机械有限公司 | Automobile exhaust pipe noise elimination processing method |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105545412A (en) * | 2016-02-23 | 2016-05-04 | 偃师市宇龙金属加工厂 | Exhaust silencer for internal combustion engine |
| CN105545413A (en) * | 2016-02-23 | 2016-05-04 | 偃师市宇龙金属加工厂 | Multi-air-chamber exhaust silencer for internal combustion engine |
| CN105673138A (en) * | 2016-02-23 | 2016-06-15 | 偃师市宇龙金属加工厂 | Multi-gas-chamber cyclone silencing method of internal combustion engine |
| CN106683657A (en) * | 2016-11-30 | 2017-05-17 | 湖州益环环保工程有限公司 | Efficient silencer capable of changing exhaust position |
| CN106683657B (en) * | 2016-11-30 | 2020-10-13 | 湖州益环环保工程有限公司 | High-efficient muffler of convertible exhaust position |
| CN115653710A (en) * | 2022-12-29 | 2023-01-31 | 中国石油大学(华东) | Airflow silencer for engine and working method |
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Application publication date: 20150826 |