CN104948263A - Expansion and resonance compound type silencer - Google Patents

Abstract

The invention discloses an expansion and resonance compound type silencer which comprises a sleeve. One end of the sleeve is sealed and inserted in an air inlet pipe in the radial direction, and an air outlet pipe is axially arranged at the other end of the sleeve. Four partition plates are sequentially parallelly arranged in the sleeve to divide the inside of the sleeve into five chambers. An inner insertion pipe extends into the third chamber from the first chamber, a perforated pipe extends into the second chamber from the third chamber and is sealed through a first partition plate, a middle pipe extends into the fourth chamber through the second chamber, and a resonant cavity insertion pipe extends into the fifth chamber from the fourth chamber. A side wall of the air inlet pipe is provided with a plurality of first through holes, and the area of a side wall of the perforated pipe located in the second chamber is provided with a plurality of second through holes. The expansion and resonance compound type silencer is reasonably combined through expansion and resonance, the high frequency silencing effect is considered while the low-frequency and medium-frequency noises of air flow are greatly reduced, the high silencing amount and a wide silencing frequency band are obtained, exhaust noises are effectively reduced; and the expansion and resonance compound type silencer is small in pressure loss, has a small influence on engine power loss, is reasonable in design and has good application prospect.

Description

An expansion resonance compound muffler

technical field

The invention relates to the field of vibration reduction and noise reduction, in particular to an expansion resonance composite muffler for engineering machinery.

Background technique

The muffler is installed on the engine exhaust pipe, and its main function is to reduce the exhaust noise of the engine, so as to reduce the noise around the driver's ear and the sound radiation to the external environment, effectively reduce the exhaust noise, reduce the environmental pollution caused by noise, and improve the operating comfort sex.

Due to the limitation of the installation space of construction machinery vehicles, in order to obtain good noise reduction in the existing design of diesel engine exhaust mufflers, the internal structure is generally relatively complicated, and the exhaust back pressure is large, resulting in large engine power loss and fuel consumption. Big, polluting the environment. The construction machinery industry has relatively strict requirements on noise limits. The noise generated by the engine accounts for a large part of the noise generated by the whole machine. Therefore, the role of the muffler is very important. However, the noise reduction effect of the existing muffler is generally not ideal for low-frequency noise. Noise is the main noise source of the whole machine. Therefore, it is necessary to design a muffler with large noise reduction and low exhaust back pressure, which can greatly improve the noise reduction performance of the muffler in the middle and low frequency bands while ensuring that the engine power is not reduced.

Contents of the invention

The object of the present invention is to solve the problems existing in the existing diesel engine mufflers for engineering machinery, overcome the above-mentioned shortcomings, and provide a kind of expansion resonance composite muffler which has large sound transmission loss and small power loss, and can meet the vehicle installation space, reducing the Environmental pollution of noise to improve driver's operating comfort.

In order to solve the problems in the prior art and achieve the above purpose, the technical solution adopted in the present invention is: comprising a sleeve with one end closed, and an air outlet pipe (12) is arranged axially at the other end of the sleeve;

The interior of the sleeve is arranged in parallel with partition I (3), partition II (5), partition III (7) and partition IV (9) in sequence from one end to the other end. Plate II (5), partition III (7) and partition IV (9) divide the inside of the sleeve into first chamber (2), second chamber (4) and third chamber (6) , the fourth chamber (15) and the fifth chamber (13);

The inner intubation tube (20) extends from the first chamber (2) to the third chamber (6), and the perforated tube (18) extends from the third chamber (6) to the second chamber (4). The partition I (3) is closed, the middle pipe (8) extends from the second chamber (4) to the fourth chamber (15), and the resonant cavity insertion pipe (10) coaxial with the middle pipe (8) is inserted from the second chamber (4). The fourth chamber (15) extends into the fifth chamber (13);

The intake pipe (1) radially extends into the first chamber (2) in the sleeve, and the side wall of the intake pipe (1) is provided with a plurality of through holes I (21);

The area inside the second chamber (4) on the side wall of the perforated pipe (18) is provided with a plurality of through holes II (19).

The inner insertion tube (20) is connected with the partition I (3) and the partition II (5); the inlet of the inner insertion tube (20) passes through the partition I (3) and extends into the first chamber (2) , the outlet extends through the partition II (5) into the third chamber (6), and the length of the outlet extending into the third chamber (6) is 1/2 of the length of the third chamber (6).

The number of perforated pipes (18) is 1, which is connected with the partition I (3) and partition II (5), and the inlet passes through the partition II (5) and extends to the length of the third chamber (6) 1/3 of the length of the third chamber (6).

The intermediate pipe (8) passes through the partition II (5) and the partition III (7) and is connected with the partition II (5) and the partition III (7), and the inlet passes through the partition II (5) and extends into The length to the second chamber (4) is 1/9 of the length of the second chamber (4), and the length of the outlet extending through the partition III (7) to the fourth chamber (15) is the fourth chamber (15) 1/2 of the length.

The resonant cavity insertion tube (10) is connected with the partition IV (9), the length of the inlet extending into the fourth chamber (15) is 1/6 of the length of the fourth chamber (15), and the outlet extends into the fourth chamber (15). The length of the five chambers (13) is 1/2 of the length of the fifth chamber (13).

The intermediate tubes (8) and the resonant cavity insertion tubes (10) are multiple and in one-to-one correspondence, and are evenly distributed along the circumference.

There is one perforated pipe (18) located on the central axis of the sleeve.

There are multiple inner insertion tubes (20), which are evenly distributed along the circumference.

The partitions I (3), II (5), III (7) and IV (9) are arranged along the radial direction of the sleeve and are connected and fixed to the inner wall of the sleeve.

The sleeve includes an outer cylinder (11) and an inner cylinder (22), and the insulation material (17) is filled between the outer cylinder (11) and the inner cylinder (22), so as to reduce heat from the outer cylinder from being transmitted into the engine compartment and causing The internal temperature is too high.

The airflow exhausted by the engine enters the intake pipe and passes through the first chamber, the third chamber, the second chamber and the fourth chamber in sequence, and part of the airflow enters the fifth chamber to form resonance and reduce the exhaust noise. The outlet pipe is discharged. The first chamber and the second chamber are perforated expansion chambers, which consume high-frequency sound energy by the friction between the air flow and the holes; the third chamber and the fourth chamber are ordinary expansion chambers, which rely on the reflection and interference caused by the sudden change of the pipe section to reduce the emission. Gas noise; the fifth chamber is a resonant cavity, which is connected with the fourth chamber through an insertion tube to form a Helmholtz resonant cavity, which absorbs a large amount of sound energy through resonance, thereby reducing low-frequency exhaust noise.

The beneficial effects are: the muffler of the present invention is rationally combined with expansion and resonance to greatly reduce airflow noise at low and medium frequencies while taking into account the effect of high-frequency silencing, obtain a larger amount of silencing and a wider silencing frequency band, and effectively reduce exhaust emissions. At the same time, the pressure loss of this structure is small, and the influence on the engine power loss is small, the design is reasonable, and it has a good application prospect.

Description of drawings

Fig. 1 is a structural schematic diagram of the present invention.

Fig. 2 is a three-dimensional structure diagram of the present invention.

In the figure: 1. Intake pipe; 2. First chamber; 3. Partition I; 4. Second chamber; 5. Partition II; 6. Third chamber; 7. Partition III; 8. Middle Tube; 9. Partition IV; 10. Resonant cavity insertion tube; 11. Outer cylinder; 12. Outlet tube; 13. Fifth chamber; 14. Resonant cavity insertion tube; 15. Fourth cavity; 16. Intermediate tube 17. Heat insulation material; 18. Perforated pipe; 19. Through hole II; 20. Inner tube; 21. Through hole I; 22. Inner cylinder;

Detailed ways

The present invention will be further described below in conjunction with accompanying drawing.

As shown in Fig. 1 and Fig. 2: an impedance compound muffler of the present invention includes an outer cylinder 11, an inner cylinder 22, an outer end cover 23, an inner end cover 24, an air inlet pipe 1, an air outlet pipe 12, a partition I3, a partition Plate II5, partition III7, partition IV9, perforated tube 18, intermediate tubes 8, 16, resonance cavity insertion tubes 10, 14, inner insertion tube 20, etc.

The outer cylinder 11 is sheathed outside the inner cylinder 22 and is coaxial with the inner cylinder 22 , and a heat insulating material 17 is filled between the outer cylinder 11 and the inner cylinder 22 .

One end of the outer cylinder 11 and the inner cylinder 22 is closed by the outer end cover 23 and the inner end cover 24 respectively, and an air inlet pipe 1 extending radially into the inner cylinder 22 and reaching the inner wall of the inner cylinder 22 is provided at this end, and the other end is axially A trachea 12 is set.

The interior of the inner cylinder 22 is arranged in parallel from one end to the other end with partitions I3, partitions II5, partitions III7 and partitions IV9, and the inner cylinder 22 is divided by partitions I3, partitions II5, partitions III7 and partitions IV9. The interior of the chamber is sequentially divided into a first chamber 2 , a second chamber 4 , a third chamber 6 , a fourth chamber 15 and a fifth chamber 13 . The partitions I3 , II5 , III7 and IV9 are arranged along the radial direction of the inner cylinder 22 , and are connected and fixed to the inner wall of the inner cylinder 22 .

The intake pipe 1 extends into the first chamber 2 , the interior of the intake pipe 1 is hollow, and a plurality of evenly distributed oblong through holes I21 are opened on the side wall in the area inside the first chamber 2 .

The inlet end of the air outlet pipe 12 extends into the fourth chamber 15 , and the outlet end extends to the outside of the inner cylinder 22 and the outer cylinder 11 .

The inner intubation tube 20 is several, and the inside is hollow, passing through the partition I3 and the partition II5, and welded together with the partition I3 and the partition II5, and the inlet passes through the partition I3 and extends into the first chamber 2 Among them, the outlet passes through the partition II5 and extends into the third chamber 6, and is evenly distributed along the circumference.

The number of said perforated pipe 18 is 1, the interior is hollow, passes through the partition II5, and is welded together with the partition I3 and the partition II5, and the entrance passes through the partition II5 and extends into the length of the third chamber 6 It is about 1/3 of the length of the third chamber, and the outlet end is welded on the partition I3 and closed by the partition I3. A plurality of oblong through-holes II19 are opened on the side wall of the perforated tube 18 inside the second chamber 4 , and the through-holes II19 are uniformly arranged along the circumference of the perforated tube 18 . Preferably, the perforated tube 18 is coaxial with the inner barrel 22 and is located at the center of the circle surrounded by the plurality of inner cannulae 20 .

The intermediate pipes 8 and 16 are multiple, hollow inside, passing through the partitions II5 and III7 and welded together with the partitions II5 and III7, distributed evenly along the circumference, and the inlets extend through the partitions II5 The length to the second chamber 4 is about 1/4 of the length of the second chamber, and the length of the outlet extending through the partition III7 to the fourth chamber 15 is about 1/2 of the length of the fourth chamber 15 .

The resonant cavity insertion tubes 10, 14 are multiple, hollow inside, passing through the partition IV9 and welded together with the partition IV9, evenly distributed along the circumference, and corresponding to a plurality of intermediate tubes 8, 16 one by one Coaxial, the length of the entrance extending into the fourth chamber 15 is about 1/4 of the length of the fourth chamber 15, and the length of the outlet extending into the fifth chamber 13 is about 1/2 of the length of the fifth chamber 13 . Preferably, the diameter of the cavity insertion tubes 10 , 14 is smaller than the diameter of the intermediate tubes 8 , 16 .

After the airflow exhausted by the engine enters the intake pipe 1, it enters the first chamber 2 through the through hole I21 on the intake pipe 1, enters the third chamber 6 through the inner insertion pipe 20, and enters the third chamber 6 through the through hole II19 of the perforated pipe 18. The second chamber 4 enters the fourth chamber 15 through the intermediate pipes 8 and 16, and part of the air enters the fifth chamber 13 from the fourth chamber 15 through the resonant cavity insertion pipes 10 and 14 to form resonance and reduce exhaust noise. , and finally the remaining air in the fourth chamber 15 is discharged through the outlet pipe 12 .

As mentioned above, a similar technical solution can be derived in combination with the content of the solution given in the accompanying drawings, such as changing the oblong hole to a round hole, etc. However, any simple modifications, dimensional changes, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still belong to the scope of the technical solution of the present invention.

Claims (10)

1. A kind of expansion resonance compound muffler, it is characterized in that, It includes a sleeve with one end closed, and an air outlet pipe (12) is arranged axially at the other end of the sleeve; The interior of the sleeve is arranged in parallel with partition I (3), partition II (5), partition III (7) and partition IV (9) in sequence from one end to the other end. Plate II (5), partition III (7) and partition IV (9) divide the inside of the sleeve into first chamber (2), second chamber (4) and third chamber (6) , the fourth chamber (15) and the fifth chamber (13); The inner intubation tube (20) extends from the first chamber (2) to the third chamber (6), and the perforated tube (18) extends from the third chamber (6) to the second chamber (4). The partition I (3) is closed, the middle pipe (8) extends from the second chamber (4) to the fourth chamber (15), and the resonant cavity insertion pipe (10) coaxial with the middle pipe (8) is inserted from the second chamber (4). The fourth chamber (15) extends into the fifth chamber (13); The intake pipe (1) radially extends into the first chamber (2) in the sleeve, and the side wall of the intake pipe (1) is provided with a plurality of through holes I (21); The area inside the second chamber (4) on the side wall of the perforated pipe (18) is provided with a plurality of through holes II (19). 2. An expansion resonance compound muffler according to claim 1, characterized in that the inner insertion pipe (20) is connected with the partition I (3) and the partition II (5); the inner insertion pipe (20 ) The inlet passes through the partition I (3) and extends into the first chamber (2), the outlet passes through the partition II (5) and extends into the third chamber (6), and the outlet extends into the third chamber The length in the chamber (6) is 1/2 of the length of the third chamber (6). 3. An expansion resonance composite muffler according to claims 1 and 2, characterized in that the number of perforated pipes (18) is 1, which are connected with the partition I (3) and partition II (5) , the length of the inlet extending through the partition II (5) into the third chamber (6) is 1/3 of the length of the third chamber (6). 4. An expansion resonance composite muffler according to claim 1, characterized in that the intermediate pipe (8) passes through the partition II (5) and partition III (7) and connects with the partition II (5), The partitions III (7) are connected together, the inlet passes through the partition II (5) and extends into the second chamber (4), the length of which is 1/9 of the length of the second chamber (4), and the outlet passes through the partition The length of III (7) extending into the fourth chamber (15) is 1/2 of the length of the fourth chamber (15). 5. An expansion resonance compound muffler according to claim 1, 4, characterized in that the resonant cavity insertion pipe (10) is connected with the partition IV (9), and the entrance extends into the fourth chamber ( The length of 15) is 1/6 of the length of the fourth chamber (15), and the length of the outlet extending into the fifth chamber (13) is 1/2 of the length of the fifth chamber (13). 6. The expansion-resonance composite muffler according to claim 1, characterized in that, the intermediate pipe (8) and the resonant cavity insertion pipe (10) are multiple and correspond to each other, and are evenly distributed along the circumference. 7. The expansion resonance composite muffler according to claim 1, characterized in that there is one perforated pipe (18) located on the central axis of the sleeve. 8. The expansion-resonance compound muffler according to claim 1, characterized in that there are multiple inner tubes (20) uniformly distributed along the circumference. 9. An expansion resonance composite muffler according to claim 1, characterized in that the partition I (3), partition II (5), partition III (7) and partition IV (9) All are arranged along the radial direction of the sleeve, and are connected and fixed with the inner wall of the sleeve. 10. An expansion resonance composite muffler according to claim 1, characterized in that the sleeve comprises an outer cylinder (11) and an inner cylinder (22), and the outer cylinder (11) and the inner cylinder (22) The space is filled with heat insulating material (17).