CN2921306Y

CN2921306Y - Impedance composite noise silencer

Info

Publication number: CN2921306Y
Application number: CN 200620110861
Authority: CN
Inventors: 尹明善; 李豫玲; 尤越
Original assignee: Lifan Industry Group Co Ltd
Current assignee: Lifan Technology Group Co Ltd
Priority date: 2006-06-28
Filing date: 2006-06-28
Publication date: 2007-07-11
Anticipated expiration: 2016-06-28

Abstract

The utility model discloses an impedance composite muffler, whose casing is divided into four expansion cavities; one end of an air inlet pipe is connected to the air inlet on a front end cap, the other end goes through a front partition plate into Expansion Cavity I. Several vent holes are provided on the front partition plate; Expansion Cavity II is communicated with Expansion Cavity III via a muffling tube, a U-shaped muffling tube assembly is provided in the casing, the closed end of said muffling tube assembly is located in Expansion Cavity II, an opening of its open end is located in Expansion Cavity III, and the other opening in Expansion Cavity IV, so that Expansion Cavities III and IV are communicated via said muffling tube assembly; sound absorbing cotton is provided in Expansion Cavity IV. The utility model combines the advantages of reactive and resistive mufflers, muffles all noise effectively in the full frequency range, and is characterized by ease of application, reliable performance, and wide scope of application and suitability for extended popularization.

Description

Impedance complex formula silencing apparatus

Technical field

The utility model relates to a kind of internal combustion engine exhaust silencer, especially impedance complex formula silencing apparatus.

Background technique

At present, general exhaust silencer for internal-combustion engine generally adopts dissipative muffler and two kinds of structures of reactive muffler.Reactive muffler is made of parts such as housing, end cap, dividing plate, suction tude, hush tube and " U " shape hush tube assemblies, end cap is located at the two ends of housing, the inside of housing generally is separated into three expansion chambers by two dividing plates, wherein first expansion chamber is by suction tude and exterior, be communicated with by hush tube between first expansion chamber and second expansion chamber and between second expansion chamber and the 3rd expansion chamber, and the 3rd expansion chamber is by " U " shape hush tube assembly and exterior.It is by repeatedly changing the flow direction of air-flow, make some frequency or frequency range noise section reflect back, make this part noise can not pass through silencing apparatus, thereby reach the noise elimination purpose.Reactive muffler is better for the noise elimination effect of medium and low frequency noise, and is inapplicable for high-frequency noises.In addition, owing to be communicated with by lacking hush tube between its first expansion chamber and second expansion chamber, resistance was bigger when airflow passes was lacked hush tube, was easy to generate abnormal sound; And the heat energy in the air-flow can not rapid diffusion, makes the first expansion cavity temperature high especially, causes the housing variable color of this part and influences the noise elimination effect.

Dissipative muffler mainly is to utilize suitably to arrange sound-absorbing material in pipeline, the acoustic energy in the extraction duct partly, and its performance depends on sound-absorbing material and sound absorption structure.It is better for the noise elimination effect of high-frequency noises, and is inapplicable for the medium and low frequency noise.Along with offseting the progressively raising that sound effective value requires, the silencing apparatus of single structure is difficult to meet the demands.

The model utility content

For solving above technical problem, the purpose of this utility model is to provide the respond well impedance complex formula silencing apparatus of eliminating the noise in a kind of whole frequency range.

The technical solution of the utility model is as follows: a kind of impedance complex formula silencing apparatus, comprise housing, front cover, rear end cover, suction tude, hush tube, " U " shape hush tube assembly and dividing plate, on front cover, have inlet hole, have exhaust port on the rear end cover, its key is: enclosure interior is separated into four expansion chambers by three dividing plates, is followed successively by II, I, III, IV from front to back; Inlet hole on described suction tude one end and the front cover joins, dividing plate extend in the I expansion chamber before the other end passed, on preceding dividing plate, be distributed with several vents, the I expansion chamber is communicated with the II expansion chamber, and be communicated with by hush tube between II expansion chamber and the III expansion chamber; The closed end of described " U " shape hush tube assembly is arranged in the II expansion chamber, an opening of its opening end is arranged in the III expansion chamber, another opening is arranged in the IV expansion chamber, makes between III expansion chamber and the IV expansion chamber to be communicated with by this hush tube assembly; In the IV expansion chamber, be provided with first perforated retainer and second perforated retainer, in the toroidal cavity between the cavity between first perforated retainer and the rear end cover and second perforated retainer and the housing acoustical cotton be housed all.

The utility model changes three expansion chambers of former reactive muffler enclosure interior into four, and acoustical cotton is set in the IV expansion chamber simultaneously, constitutes the impedance complex structure.Can both be well absorbed regardless of the noise or the noise of high frequency that are low and medium frequency like this, thereby reach the respond well purpose of eliminating the noise in the whole frequency range.Simultaneously, be communicated with to change into by short hush tube between former I expansion chamber and II expanded and on preceding dividing plate, open pore, when making high velocity air flow to the II expansion chamber by the I expansion chamber, with the vent friction by vent, make acoustic energy change into heat energy, obtain effective attenuation; Simultaneously, because shorter by area, hush tube is big.

For realizing better eliminating the noise effect, be provided with the suction tude housing in the outside of above-mentioned suction tude, in the cavity between this suction tude housing and the suction tude glass fibre is housed, and is distributed with sound-absorption hole on the suction tude tube wall corresponding with cavity.

Above-mentioned hush tube assembly is made of hush tube, bridge piece and muffler tail pipe, wherein bridge piece is arranged in the II expansion chamber, two opening is connected with the exhaust end of hush tube and the inlet end of muffler tail pipe respectively, the inlet end of described hush tube is arranged in the III expansion chamber, and the exhaust end of muffler tail pipe is arranged in the IV expansion chamber.

Be provided with the tail pipe housing in the outside of above-mentioned muffler tail pipe, in the cavity between this tail pipe housing and the muffler tail pipe glass fibre be housed, and be distributed with sound-absorption hole on the muffler tail pipe tube wall corresponding with cavity.

It is I expansion chamber volume＞II expansion chamber volume＞III expansion chamber volume＞IV expansion chamber volume that the volume of four expansion chambers of above-mentioned enclosure interior sorts by size.

Beneficial effect: the utility model integrates the advantage of reactive muffler and dissipative muffler, all can realize good noise elimination effect for the noise in the whole frequency range, and it is implemented easily, and reliable performance is widely applicable, is suitable for large-scale promotion and uses.

Description of drawings

Fig. 1 is a structural representation of the present utility model.

Fig. 2 is the structural representation of preceding dividing plate of the present utility model.

Embodiment

The utility model is described in further detail below in conjunction with drawings and Examples:

As shown in Figure 1 and Figure 2, front cover 2 and rear end cover 3 are separately positioned on the rear and front end of housing 1, and the flangikng of front cover 2 wherein rolls together with the front end of housing 1; The flangikng of rear end cover 3 rolls together with the rear end of housing 1.The inside of housing 1 is separated into four expansion chambers by three dividing

plates

9,10,11, be followed successively by II, I, III, IV from front to back, it is I expansion chamber volume＞II expansion chamber volume＞III expansion chamber volume＞IV expansion chamber volume that the volume of four expansion chambers sorts by size.On front cover 2, have inlet hole 2a, have exhaust port 3a on the rear end cover 3.The inlet end of described inlet hole 2a and suction tude 4 joins, dividing plate 9 extend in the I expansion chamber before the exhaust end of suction tude 4 passed, on preceding dividing plate 9, be distributed with several vents 9a I expansion chamber and II expansion chamber are communicated with, and the II expansion chamber communicates with the III expansion chamber by hush tube 5.Be that dividing plate 9 extend in the II expansion chamber before the inlet end of hush tube 5 passed, its exhaust end passes central diaphragm 10 and extend in the III expansion chamber.Another root hush tube 6 be arranged in parallel with hush tube 5, its inlet end is arranged in the III expansion chamber, its exhaust end passes central diaphragm 10 and preceding dividing plate 9 successively, and be connected with the inlet end of muffler tail pipe 8 by bridge piece 7, the exhaust end of this muffler tail pipe 8 passes central diaphragm 10 and rear bulkhead 11 successively, extend in the IV expansion chamber.Hush tube 6, bridge piece 7 and muffler tail pipe 8 are formed the hush tube assembly, become " U " shape.That first perforated retainer, 12, the first perforated retainers 12 are housed is vertical with the shaft axis of housing 1 in the inboard of rear end cover 3 in the IV expansion chamber, and in the cavity between this first perforated retainer 12 and the rear end cover 3 acoustical cotton 14 is housed; Second perforated retainer 13 is housed between first perforated retainer 12 and rear bulkhead 11, and this second perforated retainer 13 is a tubular, and its bottom surface and rear bulkhead 11 recline, the outside horizontal flange of its opening end, and this horizontal flange and first perforated retainer 12 recline.Between second perforated retainer 13 and housing 1, form toroidal cavity, and in this toroidal cavity acoustical cotton 14 is housed also.

From Fig. 1, can further find out, the big rear end of suction tude 4 front ends is little, coated outside in suction tude 4 has suction tude housing 4a, form cavity between the small end of suction tude 4 and the suction tude housing 4a, in in this cavity glass fibre 4b is housed, and is distributed with sound-absorption hole 4c on suction tude 4 tube wall corresponding with cavity.Coated outside at muffler tail pipe 8 has tail pipe housing 8a, is formed with cavity between this tail pipe housing 8a and the muffler tail pipe 8, and glass fibre 8b is housed in this cavity, and is distributed with sound-absorption hole 8c on muffler tail pipe 8 tube wall corresponding with cavity.

The utility model in use, inlet hole 2a on the front cover 2 joins by outlet pipe and motor, the waste gas that comes out from engine emission enters the I expansion chamber by outlet pipe and suction tude 4 and expands, buffering, enter the II expansion chamber by the vent 9a on the preceding dividing plate 9 then, in the II expansion chamber, expand, after the buffering, enter in the III expansion chamber by hush tube 5 and to expand, buffering, again successively by hush tube 6, bridge piece 7 and muffler tail pipe 8, enter the IV expansion chamber, in the IV expansion chamber, expand, after the buffering, discharge by the exhaust port 3a on the rear end cover 3 at last.For the medium and low frequency noise, when flowing in housing 1 owing to waste gas, flow direction repeatedly changes, and makes airflow direction and acoustic streaming direction constantly change, and air-flow and acoustic streaming partly break away from, and produce phase difference, and the damping coefficient of sound wave increases, and noise descends; For high-frequency noises, then absorb by glass fibre 4b, glass fibre 8b and acoustical cotton 14.

Claims

1, a kind of impedance complex formula silencing apparatus, comprise housing (1), front cover (2), rear end cover (3), suction tude (4), hush tube (5), " U " shape hush tube assembly and dividing plate, on front cover (2), have inlet hole (2a), have exhaust port (3a) on the rear end cover (3), it is characterized in that:

A, housing (1) inside are separated into four expansion chambers by three dividing plates (9,10,11), are followed successively by II, I, III, IV from front to back; Inlet hole (2a) on described suction tude (4) one ends and the front cover (2) joins, the other end passes preceding dividing plate (9) and extend in the I expansion chamber, on preceding dividing plate (9), be distributed with several vents (9a), the I expansion chamber is communicated with the II expansion chamber, and be communicated with by hush tube (5) between II expansion chamber and the III expansion chamber;

The closed end of B, described " U " shape hush tube assembly is arranged in the II expansion chamber, an opening of its opening end is arranged in the III expansion chamber, another opening is arranged in the IV expansion chamber, makes between III expansion chamber and the IV expansion chamber to be communicated with by this hush tube assembly;

C, in the IV expansion chamber, be provided with first perforated retainer (12) and second perforated retainer (13), in the toroidal cavity between cavity between first perforated retainer (12) and the rear end cover (3) and second perforated retainer (13) and the housing (1) acoustical cotton (14) be housed all.

2, impedance complex formula silencing apparatus according to claim 1, it is characterized in that: be provided with suction tude housing (4a) in the outside of suction tude (4), in the cavity between this suction tude housing (4a) and the suction tude (4) glass fibre (4b) is housed, and is distributed with sound-absorption hole (4c) on suction tude (4) tube wall corresponding with cavity.

3, impedance complex formula silencing apparatus according to claim 1, it is characterized in that: described hush tube assembly is made of hush tube (6), bridge piece (7) and muffler tail pipe (8), wherein bridge piece (7) is arranged in the II expansion chamber, two opening is connected with the exhaust end of hush tube (6) and the inlet end of muffler tail pipe (8) respectively, the inlet end of described hush tube (6) is arranged in the III expansion chamber, and the exhaust end of muffler tail pipe (8) is arranged in the IV expansion chamber.

4, impedance complex formula silencing apparatus according to claim 3, it is characterized in that: be provided with tail pipe housing (8a) in the outside of muffler tail pipe (8), in the cavity between this tail pipe housing (8a) and the muffler tail pipe (8) glass fibre (8b) is housed, and is distributed with sound-absorption hole (8c) on muffler tail pipe (8) tube wall corresponding with cavity.

5, impedance complex formula silencing apparatus according to claim 1 is characterized in that: it is I expansion chamber volume＞II expansion chamber volume＞III expansion chamber volume＞IV expansion chamber volume that the volume of inner four expansion chambers of described housing (1) sorts by size.