CN2245124Y

CN2245124Y - Exhaust silencer for car

Info

Publication number: CN2245124Y
Application number: CN 95227884
Authority: CN
Inventors: 李孝宽; 李孝平
Original assignee: Beijing Municipal Institute of Labour Protection
Current assignee: Beijing Municipal Institute of Labour Protection
Priority date: 1995-12-15
Filing date: 1995-12-15
Publication date: 1997-01-15
Anticipated expiration: 2005-12-15

Abstract

The utility model relates to an exhaust silencer for a car, which belongs to an exhaust noise reducing device of a car engine. The exhaust silencer for a car is generally composed of an air inlet pipe, an exhaust pipe, an expansion chamber, etc. The exhaust silencer for a car of the utility model is provided with a steady flow chamber, and a group of interference elements which are composed of a pair of cross deformed pipe pieces is arranged in the steady flow chamber for forming an interference unit. The interference unit can efficiently reduce the exhaust noise of the engine. Under the condition of the same volume, compared with the original silencer, the exhaust silencer for a car can reduce the noise of the complete car by 1.5 to 2dB (A). If the exhaust silencer for a car is used on the car with relatively low engine noise, better noise reducing effect of the complete car can be obtained.

Description

Automobile exhaust muffler

The utility model is a kind of silencer that is used to reduce engine exhaust noise, particularly is applicable to the silencer that reduces the automobile exhaust noise.

Silencer for automobile adopts the expansion chamber structure more both at home and abroad at present, and a small amount of employing resonance structure is also arranged, and these structures all need to increase the silencing apparatus volume and improve the noise elimination effect, and the excessive practicability that just lost of volume.Therefore, to reach national regulation noise standard limit value difficulty bigger for the automobile exhaust noise.

The purpose of this utility model provides a kind of novel exhaust silencing apparatus, and it is little that this silencing apparatus has a volume, and noise elimination obvious results characteristics are particularly obvious in low-frequency range noise elimination effect.

Exhaust silencer mainly is made up of suction tude (1), interference element (2,3), plenum chamber (4), expansion chamber (6,10,12), perforation core pipe (7,11), shell (13), internal partition (5,8,9) outlet pipe parts such as (15), referring to accompanying drawing.Each parts of silencing apparatus are made by general steel plate.Suction tude (1) is connected with interference element (2), and interference element is arranged in plenum chamber (4), and both form an interference unit, and this interference element is a pair of converting pipe, and two pipes are criss-crossing (referring to attached Fig. 1 and 2), and element (3) is connected with perforation core pipe (7).Separate with internal partition C between perforation core pipe (7) and the perforation core pipe (10), have some apertures on the core tube wall, the number in hole and layout design according to air-flow (sound wave) parameter.Perforation core pipe (11) is connected with outlet pipe (15), around the internal partition several apertures is arranged, as air-flow path.Front cover (16) and rear end cover (14) are used to seal the front/rear end of silencing apparatus.

The working principle of this silencing apparatus is: suction tude (1) connects engine exhaust pipe, the gas that motor is discharged enters interference element (2,3), the part of air-flow (sound wave) directly enters perforation core pipe (7) by central passage, another part air-flow then enters plenum chamber (4) by collateral branch's passage of interference element (2), the collateral branch's passage that passes through interference element (3) again enters in the perforation core pipe (7) (as shown in Figure 6), because air-flow (sound wave) has passed through the propagation path of different length at center portion passage and collateral branch's passage, produce acoustic interference effects at two passage concourses, can eliminate a part of exhaust sound effectively.After air-flow enters perforation core pipe (7), enter expansion chamber A and expansion chamber B by the hole on the perforation core tube wall, air-flow in two expansion chamber enters expansion chamber B and C successively by the hole on dividing plate (8) and (9) respectively, the hole that air communication is crossed on perforation core pipe (11) wall in expansion chamber C enters outlet pipe (15) at last, enters atmosphere then.Behind the expansion like this of sound wave process, the contraction process, further obtain decay, thereby reach the purpose of noise elimination.

Description of drawings.Fig. 1 is the automobile exhaust muffler structural representation, and Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6 are respectively the cross-sectional view of position shown in this silencing apparatus A-A, B-B, C-C, D-D, the E-E.Among the figure: 1-suction tude, 2,3-interference element, 4-plenum chamber, 5-internal partition A, 6-expansion chamber A, 7-perforation core pipe A, 8-internal partition B, 9-internal partition C, 10-expansion chamber B, 11-perforation core pipe B, 12-expansion chamber C, 13-shell, 14-rear end cover, 15-outlet pipe, 16-front cover.

The automotive muffler that the utility model provides is compared with the silencer of same volume, Can effectively improve insertion loss, test result shows that the car load noise can reduce by 1.5～2dB (A) if be used for the relatively low vehicle of engine noise, will have better The entire car denoise effect.

Embodiment.The used engine exhaust amount of certain homemade light truck is 3.856 liters, what adopt is Japan Isuzu Motors automobile exhaust gas silencing apparatus, after using this silencing apparatus identical instead with its volume, car load noise decline 1.5～2dB (A), under vehicle fixation condition, the relief opening noise is carried out the comparison of motor different rotating speeds, measurement result shows, corresponding motor different rotating speeds can have the noise of 1～4dB (A) to reduce.Volume according to Japan Isuzu Motors automobile exhaust gas silencing apparatus, exhaust silencer external dimension provided by the invention are ∮ 178mm * 670mm, plenum chamber length is 165mm, interference element (2) and (3) are housed in plenum chamber, this element is the converting pipe of a pair of decussation, the front portion of interference element (2) is connected on the suction tude (1), and the rear portion of interference element (3) is connected on the perforation core pipe (7).Plenum chamber and interference element have been formed an interference unit.

Claims

1. automobile exhaust muffler, comprise suction tude, outlet pipe, expansion chamber, internal partition, perforation core pipe, front and rear cover, shell, it is characterized in that being provided with a plenum chamber, the interference element of forming by the distortion pipe fitting of a pair of criss-crossing in the plenum chamber (4) (2,3), interference element (2) is connected with suction tude (1), interference element (3) is connected with perforation core pipe (7), and this element is made by general steel plate.