CN206111279U - Car premuffler structure - Google Patents

Abstract

The utility model discloses a car premuffler structure, include cylindric shells and the core pipe that passes cylindric shells, the one end of the gas outlet that the air inlet and the core that are located on cylindric shells's the core pipe pipe wall and are close to the core pipe were respectively managed is equipped with soundproofing hole section I separately, it still is equipped with soundproofing hole section II on the core pipe pipe wall of two sections soundproofing hole sections between I to be located, soundproofing hole section I includes a plurality of soundproofing hole I that are used for making core intraduct and cylindric shells inner chamber communicate, soundproofing hole section II includes a plurality of soundproofing hole II that are used for making core intraduct and cylindric shells inner chamber communicate, soundproofing hole's I diameter is less than soundproofing hole's II diameter, the closeness that is located I last soundproofing hole I of soundproofing hole section is greater than the closenesses that are located II last soundproofing hole II of soundproofing hole section. The utility model discloses simple structure, the soundproofing hole section of constituteing through the soundproofing hole by different diameters sizes, different closenesses has improved sound absorption and noise reduction effect, makes the wavelength coverage of the denoising sound that disappears more broaden, frequency range is wideer, has improved whole car travelling comfort.

Description

Automobile front muffler structure

technical field

The utility model relates to an automobile muffler, in particular to a structure of an automobile front muffler.

Background technique

The exhaust muffler of a car is the main component of driving noise. All countries in the world have strict regulations on the noise limit of various vehicles, and the exhaust muffler is such a device for reducing exhaust noise. The function of the exhaust muffler is to eliminate noise by reducing and attenuating the pulsation of the exhaust pressure. According to the principle of interference, the exhaust muffler has two basic noise reduction methods: absorption and reflection. The absorption muffler reduces the energy of the exhaust gas through friction on sound-absorbing materials such as glass fiber, steel fiber and asbestos; the reflection muffler has multiple harmonic chambers connected in series and porous reflection tubes of different lengths. After multiple reflections, collisions, expansions, and coolings, the pressure is reduced, vibration and energy are reduced.

There are usually two mufflers installed in a car exhaust system: a front muffler and a rear muffler. The front muffler is basically a resistant muffler, mainly for some specific frequencies; the rear muffler can be a resistant muffler or a composite muffler, which is used to eliminate noise in a wider frequency band. But at present, the front muffler on the car usually only opens a section of muffler holes composed of a number of muffler holes with the same diameter on the core tube for muffler. The range is small and the frequency range is short, which affects the comfort of the vehicle.

Utility model content

Aiming at the deficiencies of the above-mentioned prior art, the technical problem to be solved by the utility model is: how to provide an automobile front muffler structure with good noise reduction effect and improved vehicle comfort.

In order to solve the above technical problems, the utility model adopts the following technical solutions:

A car front muffler structure, comprising a cylindrical shell and a core tube passing through the cylindrical shell, characterized in that: the core tube walls are located in the cylindrical shell and are respectively close to the core tube One end of the air inlet of the core tube and the air outlet of the core tube is respectively provided with a muffler hole section I, and the wall of the core tube between the two sections of the muffler hole section I is also provided with a muffler hole section II, The muffler hole section I includes a number of muffler holes I for connecting the inside of the core tube with the inner cavity of the cylindrical shell, and the muffler hole section II includes a number of muffler holes for making the inside of the core tube communicate with each other. The muffler hole II communicated with the inner cavity of the cylindrical shell, the diameter of the muffler hole I is smaller than the diameter of the muffler hole II, and the muffler hole I is located on the muffler hole section I The density is greater than the density of the noise elimination holes II located on the noise elimination hole section II.

In the utility model, the core tube located in the cylindrical shell is provided with a muffler hole section composed of muffler holes with different diameters and densities. The different diameters of the sound-absorbing holes have different wavelengths that can eliminate noise, thus increasing the range of wavelengths that can eliminate noise. The density of the sound-absorbing holes is different, and the noise frequencies targeted are different, which increases the frequency range for noise elimination. In addition, through the segmental arrangement of the muffler hole section I and the muffler hole section II, most of the low- and medium-frequency noise in the exhaust system can be eliminated, the noise reduction effect is good, and the comfort of the vehicle is improved.

As an optimization, the outer diameter of the cylindrical shell near the gas outlet of the core pipe decreases gradually along the axial direction of the cylindrical shell. After the exhaust gas enters the inner cavity of the cylindrical shell, since the distance between the core tube and the shell wall of the inclined section of the cylindrical shell is different, the time it takes for the sound to reflect back through the inclined section of the cylindrical shell It is also different and can enhance the noise reduction effect.

As an optimization, the inner surface of the straight section of the cylindrical shell is covered and bonded with sound-absorbing cotton. When the sound wave of the noise passes through the muffler cotton, the sound wave energy is absorbed by the muffler cotton and transformed into heat energy. As a resistive muffler, it mainly absorbs high-frequency noise and has a wide frequency range. In addition, the sound-absorbing cotton has a corrosion-resistant function, can adapt to the harsh working environment in the muffler, and increase the ability of sound absorption and noise reduction.

As an optimization, a quarter-wavelength tube communicating with the inner cavity of the core tube is provided on the core tube located in the cylindrical shell and near the air inlet of the core tube. The axial direction of one of the wavelength tubes is perpendicular to the axial direction of the core tube, and the projection of the quarter-wavelength tube on the radial direction of the core tube is located at the Outside the projection in the radial direction of the core tube. The quarter-wavelength tube can eliminate higher-frequency noise, making the frequency band for anechoic elimination wider.

To sum up, the beneficial effect of the utility model lies in that the utility model has a simple structure, and the effect of noise reduction and noise reduction is improved through the noise reduction hole section composed of noise reduction holes with different diameters and different densities, so that the effect of noise elimination is improved. The wavelength range is wider and the frequency band is wider, which improves the comfort of the vehicle.

Description of drawings

In order to make the purpose, technical solutions and advantages of the utility model clearer, the utility model will be further described in detail below in conjunction with the accompanying drawings, wherein:

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

detailed description

Below in conjunction with accompanying drawing, the utility model is described in further detail.

As shown in Figure 1, the structure of the automobile front muffler in this specific embodiment includes a cylindrical shell 1 and a core pipe 2 passing through the cylindrical shell 1, and the core pipe located in the cylindrical shell 1 2 On the pipe wall and one end close to the air inlet of the core tube 2 and the gas outlet of the core tube 2, respectively, there are muffler hole sections I3, and the core between the two muffler hole sections I3 The wall of the tube 2 is also provided with a muffler hole section II4, and the muffler hole section I3 includes a number of muffler holes I for connecting the inside of the core tube 2 with the inner cavity of the cylindrical shell 1, so The muffler hole section II4 includes a number of muffler holes II for connecting the interior of the core tube 2 with the inner cavity of the cylindrical shell 1, and the diameter of the muffler hole I is smaller than that of the muffler hole II. The density of the muffler holes I located on the muffler hole section I3 is greater than the density of the muffler holes II located on the muffler hole section II4.

In this specific embodiment, the outer diameter of the cylindrical shell 1 close to the air outlet of the core tube 2 gradually decreases along the axial direction of the cylindrical shell 1 .

In this specific embodiment, the inner surface of the straight section of the cylindrical shell 1 is covered and bonded with sound-absorbing cotton 5 .

In this specific embodiment, on the core tube 2 located in the cylindrical shell 1 and close to the air inlet of the core tube 2, there is also a quarter of the tube communicating with the inner cavity of the core tube 2. A wavelength tube 6, the axial direction of the quarter-wavelength tube 6 is perpendicular to the axial direction of the core tube 2, and the quarter-wavelength tube 6 is in the radial direction of the core tube 2 The projection of is located outside the projection of the muffler hole section I3 in the radial direction of the core tube 2 .

In the process of specific implementation, the number of the muffler hole section II4 is two and arranged at intervals. This can better eliminate noise.

Finally, it is noted that the above embodiments are only used to illustrate the technical solutions of the present utility model without limitation. Although the utility model has been described with reference to the preferred embodiment of the utility model, those of ordinary skill in the art should understand that, Various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

Claims (4)

1. A car front muffler structure, comprising a cylindrical shell and a core pipe passing through the cylindrical shell, characterized in that: it is located on the wall of the core pipe in the cylindrical shell and is respectively close to the One end of the air inlet of the core tube and the air outlet of the core tube is respectively provided with a muffler hole segment I, and the wall of the core tube between the two muffler hole segments I is also provided with a muffler hole segment II, the muffler hole section I includes a number of muffler holes I for connecting the inside of the core tube with the inner cavity of the cylindrical shell, and the muffler hole section II includes a number of muffler holes for making the core The muffler hole II inside the pipe communicates with the inner cavity of the cylindrical shell, the diameter of the muffler hole I is smaller than the diameter of the muffler hole II, and the muffler hole located on the muffler hole section I The density of I is greater than the density of the muffler holes II located on the muffler hole section II. 2 . The automobile front muffler structure according to claim 1 , wherein the outer diameter of the cylindrical shell near the air outlet of the core pipe gradually decreases along the axial direction of the cylindrical shell. 3 . 3. The automobile front muffler structure according to claim 2, characterized in that: the inner surface of the straight section of the cylindrical shell is covered with sound-absorbing cotton. 4. The automobile front muffler structure according to claim 1, characterized in that: on the core tube in the cylindrical shell and near the air inlet end of the core tube, there is also a A quarter-wavelength tube connected to the inner cavity of the tube, the axial direction of the quarter-wavelength tube is perpendicular to the axial direction of the core tube, and the quarter-wavelength tube is in the radial direction of the core tube The projection in the direction is outside the projection of the muffler hole segment I in the radial direction of the core tube.