Exhaust silencer of land leveler

Abstract

The utility model discloses a land leveler exhaust silencer which comprises a silencer shell, an air inlet pipe, an exhaust tail pipe, a partition plate and a perforated pipe, and the air inlet pipe and the exhaust tail pipe are installed at the two ends of the silencer shell respectively in the air inlet direction of the silencer. The three partition plates are the first partition plate, the second partition plate and the third partition plate, the three partition plates are arranged in the silencer shell in parallel and divide the interior of the silencer shell into four cavities, the perforated pipes comprise the first perforated pipe, the second perforated pipe and the third perforated pipe, the first perforated pipe and the second perforated pipe are axially installed in the second cavity, and the third perforated pipe is axially installed in the third cavity. The silencer is divided by the partition plate to form the silencing cavities, the combined effect of expansion silencing of the perforated pipes and resonance silencing of the cavities is utilized, broadband noise can be effectively eliminated, noise of multiple frequencies is considered, the fluid path is long, the silencing amount is large, and the silencing effect is good. And air velocity and pressure loss are reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of exhaust post-processing and NVH of a motor grader, and in particular to an exhaust muffler for a motor grader. Background Art

[0002] A motor grader is an important equipment widely used in the field of engineering machinery such as road construction, land leveling, and mining. In the application process of the motor grader, emission noise is a key issue that needs to be solved urgently. The exhaust system of the motor grader will generate a lot of noise when working, which not only poses a threat to the health of the operator, but also causes noise pollution to the surrounding environment. In order to meet this challenge, modern motor graders are usually equipped with exhaust mufflers. The function of the exhaust muffler is to reduce the exhaust noise by reducing the exhaust pressure and attenuating the pulsation of the exhaust pressure, thereby reducing environmental noise pollution. There are many types of existing mufflers, including resistive mufflers, reactive mufflers, and impedance composite mufflers. However, the conventional resistive muffler has poor gas flowability and easily affects the exhaust effect. Utility Model Content

[0003] Technical purpose: In view of the shortcomings of existing exhaust mufflers, the utility model discloses a grader exhaust muffler with perforation as the main structure and the long fluid path to reduce exhaust noise and optimize the muffler performance.

[0004] Technical solution: To achieve the above technical objectives, the utility model adopts the following technical solution:

[0005] A grader exhaust muffler comprises a muffler shell, an air intake pipe, an exhaust tail pipe, a partition and a perforated pipe, wherein the air intake pipe and the exhaust tail pipe are respectively installed at two ends of the muffler shell along the air intake direction of the muffler; there are three partitions, namely a first partition, a second partition and a third partition, which are arranged in parallel inside the muffler shell to divide the inside of the muffler shell into four chambers, which are respectively the first chamber, the second chamber, the third chamber and the fourth chamber along the direction from the air intake pipe to the exhaust tail pipe; the perforated pipe comprises a first perforated pipe, a second perforated pipe and a third perforated pipe, wherein the first perforated pipe and the second perforated pipe are axially installed in the second chamber, and the ends are connected with the first chamber, and the gas enters the second chamber through the first perforated pipe and the second perforated pipe, and the third perforated pipe is axially installed in the third chamber, and the end of the third perforated pipe is connected with the second chamber, and a connecting hole for connecting the third chamber with the fourth chamber is arranged on the third partition.

[0006] Preferably, the first perforated tube, the second perforated tube and the third perforated tube of the utility model are staggered along the axis direction of the muffler shell, and the perforated areas of the first perforated tube and the second perforated tube face the position of the third perforated tube.

[0007] Preferably, the perforation rates of the first perforated tube and the second perforated tube of the utility model are 20%-30%.

[0008] Preferably, the lengths of the first chamber and the fourth chamber of the utility model are between 1 / 3 and 1 / 2 of the axial length of the third chamber, and the length of the second chamber is between 1 / 4 and 1 / 3 of the axial length of the third chamber.

[0009] Preferably, the cross-sectional diameters of the air intake pipe and the exhaust tail pipe of the utility model are 1.3-1.5 times the length of the cross-sectional diameter of the first perforated pipe.

[0010] Preferably, the perforation rate of the third perforated tube of the present invention is less than 5%, the third perforated tube is perforated on both sides, and the length of the perforated area is between 1 / 3 and 1 / 2 of the length of the third chamber.

[0011] Preferably, the first perforated tube and the second perforated tube of the utility model have the same diameter and length, and the diameter of the third perforated tube is between 1 / 2 and 2 / 3 of the diameter of the first perforated tube.

[0012] Beneficial effects: The grader exhaust muffler provided by the utility model has the following beneficial effects:

[0013] 1. The utility model divides the silencer into silencer chambers by partitions, and utilizes the expansion silencer of the perforated tube and the resonance silencer of the chamber to effectively eliminate broadband noise and take into account noise of multiple frequencies. The fluid path is long, the silencer has a large amount of silencer, and the air flow rate and pressure loss are reduced.

[0014] 2. The perforated areas of the first perforated tube and the second perforated tube of the utility model are oriented toward the third perforated tube, which can increase the complexity of the sound wave path inside the muffler, thereby increasing the number of reflections, refractions and scatterings of the sound waves, helping to more effectively disperse and attenuate sound energy, thereby improving the sound elimination effect, and can help the airflow flow more smoothly when passing through the muffler, reduce flow resistance and reduce airflow noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0016] Figure 1 This is a cross-sectional view of the utility model along the axial direction of the muffler shell;

[0017] Figure 2 This is a cross-sectional structural diagram of the second chamber of the utility model;

[0018] Among them, 1-muffler shell, 2-intake pipe, 3-exhaust tail pipe, 4-first perforated pipe, 5-second perforation. DETAILED DESCRIPTION

[0019] Reference will now be made in detail to embodiments of the present disclosure, one or more examples of which are set forth herein below. Each embodiment and example is provided by explaining the apparatus, composition and materials of the present disclosure, rather than limiting. On the contrary, the following description provides a convenient illustration of an exemplary embodiment for implementing the present disclosure. In fact, it will be clear to those skilled in the art that various modifications and variations can be made in the teachings of the present disclosure without departing from the scope or spirit of the present disclosure. For example, a feature shown or described as a part of an embodiment can be used in conjunction with another embodiment to produce yet another embodiment. It is expected that the present disclosure covers such modifications and variations within the scope of the appended claims and their equivalents. Other objects, features and aspects of the present disclosure are disclosed in or clear from the following detailed description. It will be understood by those of ordinary skill in the art that this discussion is only a description of exemplary embodiments and is not intended to limit the wider aspects of the present disclosure.

[0020] like Figure 1 and Figure 2 As shown, the utility model is an exhaust muffler for a grader, comprising a muffler shell 1, an air intake pipe 2, an exhaust tail pipe 3, a partition and a perforated pipe, wherein the air intake pipe 2 and the exhaust tail pipe 3 are respectively installed at both ends of the muffler shell 1 along the air intake direction of the muffler; there are three partitions, namely a first partition 4, a second partition 5 and a third partition 6, which are arranged in parallel inside the muffler shell 1, dividing the inside of the muffler shell into four chambers, which are respectively a first chamber 7, a second chamber 8 and a third chamber 9 along the direction from the air intake pipe 2 to the exhaust tail pipe 3. and the fourth chamber 10; the perforated tube includes a first perforated tube 11, a second perforated tube 12 and a third perforated tube 13, the first perforated tube 11 and the second perforated tube 12 are axially installed in the second chamber 8, and the ends are connected with the first chamber 7, and the gas enters the second chamber 8 through the first perforated tube 11 and the second perforated tube 12, the third perforated tube 13 is axially installed in the third chamber 9, and the end of the third perforated tube 13 is connected with the second chamber 8, and a connecting hole 14 for connecting the third chamber 9 and the fourth chamber 10 is arranged on the third partition plate 6.

[0021] The length of the first chamber 7 and the fourth chamber 10 of the utility model is between 1 / 3 and 1 / 2 of the axial length of the third chamber 9, and the length of the second chamber 8 is between 1 / 4 and 1 / 3 of the axial length of the third chamber 9. The third chamber 9 is an airflow resonance chamber, which is equivalent to a Helmholtz resonant cavity. A large amount of noise is absorbed by the resonance of the gas. Resonance chambers of different volumes can eliminate low-frequency noise of different frequencies. The first chamber 7, the second chamber 8 and the fourth chamber 10 are expansion chambers. The propagation direction of the sound wave is changed by the change of the pipe cross section, and the reflection, interference and friction between the gas and the hole consume the noise energy in the pipe to achieve the purpose of silencing. By combining the expansion silencing and the resonance silencing, broadband noise can be effectively eliminated, taking into account noise of multiple frequencies. The fluid path is long, there is a large amount of silencing, and the air flow rate and pressure loss are reduced.

[0022] In a specific embodiment, the cross-sectional diameter of the intake pipe 2 and the exhaust tail pipe 3 of the utility model is 1.3-1.5 times the length of the cross-sectional diameter of the first perforated tube 11, the diameter and length of the first perforated tube 11 and the second perforated tube 12 are the same, and the diameter of the third perforated tube 13 is between 1 / 2-2 / 3 of the diameter of the first perforated tube 11; the perforation rate of the third perforated tube 13 is less than 5%, the third perforated tube 13 is perforated on both sides, and the length of the perforated area of ​​the third perforated tube 13 is between 1 / 3-1 / 2 of the length of the third chamber 9.

[0023] At the same time, if Figure 2 As shown, the arrow indicates the direction of intake air flow. The first perforated tube 11, the second perforated tube 12 and the third perforated tube 13 of the utility model are staggered along the axial direction of the muffler shell 1. The perforated areas of the first perforated tube 11 and the second perforated tube 12 are oriented toward the position of the third perforated tube 13, and the orientation of the perforated area forms a certain angle with the tangent direction of the corresponding second chamber wall, preferably an acute angle; the perforation rate of the first perforated tube 11 and the second perforated tube 12 is 20%-30%; by setting the orientation of the perforated area, the complexity of the path of the sound wave inside the muffler chamber is increased on the flow path, thereby increasing the reflection of the sound wave, improving the sound elimination effect, and making the incoming airflow flow more smoothly in the chamber, reducing the flow resistance and reducing the airflow noise.

Claims

1. A motor grader exhaust muffler, characterized in that: The muffler comprises a muffler shell (1), an air intake pipe (2), an exhaust tail pipe (3), a partition and a perforated pipe. The air intake pipe (2) and the exhaust tail pipe (3) are respectively installed at two ends of the muffler shell (1) along the air intake direction of the muffler. There are three partitions, namely a first partition (4), a second partition (5) and a third partition (6). The three partitions are arranged in parallel inside the muffler shell (1) to divide the inside of the muffler shell into four chambers, namely a first chamber (7), a second chamber (8), a third chamber (9) and a fourth chamber (10) along the direction from the air intake pipe (2) to the exhaust tail pipe (3). The perforated pipe includes a first chamber (7), a second chamber (8), a third chamber (9) and a fourth chamber (10). The invention comprises a first perforated tube (11), a second perforated tube (12) and a third perforated tube (13); the first perforated tube (11) and the second perforated tube (12) are axially installed in the second chamber (8), and their ends are connected to the first chamber (7); gas enters the second chamber (8) through the first perforated tube (11) and the second perforated tube (12); the third perforated tube (13) is axially installed in the third chamber (9), and its end is connected to the second chamber (8); a connecting hole (14) for connecting the third chamber (9) and the fourth chamber (10) is provided on the third partition plate (6).

2. The motor grader exhaust muffler according to claim 1, characterized in that: The first perforated tube (11), the second perforated tube (12) and the third perforated tube (13) are staggered along the axial direction of the muffler shell (1), and the perforated areas of the first perforated tube (11) and the second perforated tube (12) face the direction of the third perforated tube (13).

3. The motor grader exhaust muffler according to claim 2, characterized in that: The perforation rates of the first perforated tube (11) and the second perforated tube (12) are 20%-30%.

4. The motor grader exhaust muffler according to claim 1, characterized in that: The lengths of the first chamber (7) and the fourth chamber (10) are between 1 / 3 and 1 / 2 of the axial length of the third chamber (9), and the length of the second chamber (8) is between 1 / 4 and 1 / 3 of the axial length of the third chamber (9).

5. The motor grader exhaust muffler according to claim 1, characterized in that: The cross-sectional diameters of the air intake pipe (2) and the exhaust tail pipe (3) are 1.3-1.5 times the length of the cross-sectional diameter of the first perforated pipe (11).

6. The motor grader exhaust muffler according to claim 1, characterized in that: The perforation rate of the third perforated tube (13) is less than 5%, the third perforated tube (13) is perforated on both sides, and the length of the perforated area of ​​the third perforated tube (13) is between 1 / 3 and 1 / 2 of the length of the third chamber (9).

7. The motor grader exhaust muffler according to claim 1, characterized in that: The first perforated tube (11) and the second perforated tube (12) have the same diameter and length, and the diameter of the third perforated tube (13) is between 1 / 2 and 2 / 3 of the diameter of the first perforated tube (11).

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