CN105569772A - Silencer of exhaust system of motorcycle - Google Patents

Abstract

The invention provides a silencer of an exhaust system of a motorcycle. An inner cavity of a shell is sequentially divided into a first cavity, a second cavity, a third cavity and a fourth cavity; an air outlet end of a straight barrel pipe section of an air inlet pipe extends to the first cavity from an air inlet of the silencer; a three-way catalyst is arranged in an inner cavity of the straight barrel pipe section; a U-shaped pipe section penetrates through the second cavity from the first cavity, and then returns to the first cavity in a penetrating manner; the silencer further comprises a first ventilating pipe and a second ventilating pipe; the first ventilating pipe penetrates through the third cavity from the second cavity and extends into the fourth cavity; the second ventilating pipe penetrates through the fourth cavity from the third cavity; and an air outlet pipe penetrates through the fourth cavity from the third cavity and extends out of an end surface of a rear end of the shell to form an exhaust port of the silencer. Through abrupt change of the cross section and insertion of the cross section of the silencer, waste gases entering the cavities reflect and mutually interfere (rub) to achieve the silencing effect, and through increasing of an air flow path, air flow pressure and speed are reduced to reduce noises.

Description

A muffler for motorcycle exhaust system

technical field

The invention relates to the field of motorcycles, in particular to a muffler for a motorcycle exhaust system.

Background technique

The intake and exhaust system of a motorcycle includes an intake system and an exhaust system. On the engine, the part that sucks the mixed gas into the engine is called the intake system, and the part that discharges the burned exhaust gas out of the engine is called the exhaust system. The intake system includes air filter, carburetor and intake pipe, etc. After the air is filtered by the air filter, it flows through the carburetor and mixes with gasoline, enters the intake manifold through the intake pipe, and enters the engine through the intake valve to ignite and burn to generate power.

The motorcycle exhaust system includes an engine and a muffler, and the exhaust end of the engine is connected to the muffler. The muffler is a device that allows airflow to pass through and attenuates noise, so the performance of the muffler affects the noise of the motorcycle. Due to the vibration of the engine and the body of the existing motorcycle, the idling noise of the motorcycle is large. In order to solve the noise problem of motorcycles, the applicant proposed a low-noise motorcycle exhaust system, which reduces the idling noise of motorcycles, but while realizing the low-noise motorcycle exhaust system, the applicant also needs to consider how to design A muffler that reduces exhaust noise at the exhaust end of an engine.

Contents of the invention

Aiming at the above-mentioned deficiencies in the prior art, the patent of the present invention provides a muffler for the exhaust system of a motorcycle, which is used to reduce the exhaust noise of the exhaust end of the engine.

In order to solve the problems of the technologies described above, realize the purpose of the invention, the technical scheme adopted in the present invention is as follows:

A muffler for a motorcycle exhaust system, comprising a shell, and an air inlet pipe and an air outlet pipe arranged in the inner cavity of the outer shell; A partition divides the inner cavity into a first chamber, a second chamber, a third chamber and a fourth chamber, and the first partition is provided with vent holes for communicating with two adjacent chambers; The air inlet pipe includes a straight pipe section and a U-shaped pipe section. The air inlet end of the straight pipe section passes through the front end surface of the shell to form the muffler air inlet; At least one three-way catalyst is coaxially arranged in the chamber, one end of the U-shaped pipe section is connected to the gas outlet end of the straight pipe section, and the other end passes through the second chamber from the first chamber, and then bends back to the first chamber for installation; it also includes The first ventilation pipe and the second ventilation pipe, the first ventilation pipe extends from the second chamber through the third chamber into the fourth chamber; the second ventilation pipe passes through the fourth chamber from the third chamber; The air outlet pipe extends from the third chamber through the fourth chamber to the rear end surface of the casing to form an exhaust port of the muffler.

As a further optimization of the above solution, the straight pipe section of the air inlet pipe located in the first chamber is provided with a through hole.

As a further optimization of the above solution, the straight pipe section of the air inlet pipe is arranged obliquely in the inner cavity of the casing, and the end of the straight pipe section connected to the U-shaped pipe section is inclined in a direction away from the axis of the casing.

As a further optimization of the above scheme, it also includes a sound-absorbing cylinder fixed in the first chamber and the second chamber and arranged coaxially with the first chamber and the second chamber, and the sound-absorbing cylinder is staggered along the circumference of its length direction. Sound-absorbing hole; sound-absorbing cotton is laid in the gap between the sound-absorbing tube and the inner wall of the first chamber and the inner wall of the second chamber.

As a further optimization of the above solution, the exhaust port of the muffler bends downwards and extends.

Compared with the prior art, the present invention has the following advantages:

The muffler provided by the present invention, through cross-section mutation and cross-section insertion, makes the exhaust gas enter these chambers to reflect and interfere with each other (friction) to achieve the noise reduction effect, and also increases the flow of airflow and reduces the pressure and flow velocity of the airflow. noise reduction.

Description of drawings

Fig. 1 is the sectional view of the muffler of the motorcycle exhaust system provided by the present invention.

Fig. 2 is a sectional view of A-A in Fig. 1 .

Fig. 3 is a B-B sectional view in Fig. 1 .

Fig. 4 is a sectional view of C-C in Fig. 1 .

detailed description

The present invention will be further described in detail below in conjunction with examples, but the embodiments of the present invention are not limited thereto.

Example:

The muffler of the motorcycle exhaust system is shown in Figure 1-4. Comprising a shell 29, and an air inlet pipe 25 and an air outlet pipe 30 arranged in the inner chamber of the outer shell, two first baffles and a second baffle parallel to each other are successively arranged in the inner chamber of the outer shell 29, and the inner chamber Divided into a first chamber 21, a second chamber 22, a third chamber 23 and a fourth chamber 24, the first partition is provided with a ventilation hole 31 for communicating with two adjacent chambers; The air inlet pipe comprises a straight tube section and a U-shaped tube section, and the inlet end of the straight tube section passes through the front end face of the shell 29 to form the muffler air inlet; the gas outlet end of the straight tube section extends from the muffler inlet to the first chamber 21, and the At least one three-way catalyst is coaxially arranged in the inner cavity. One end of the U-shaped pipe section is connected to the gas outlet end of the straight pipe section, and the other end passes from the first chamber 21 through the second chamber 22, and then bends back to the first chamber 21. Setting; also include first air pipe 27 and second air pipe 28, the first air pipe 27 is set in the fourth chamber 24 through the third chamber 23 from the second chamber 22; the second air pipe 28 is arranged from The third chamber 23 is disposed through the fourth chamber 24; the air outlet pipe 30 extends from the third chamber 23 through the fourth chamber 24 to the rear end surface of the casing to form an exhaust port of the muffler.

The internal structure of the muffler shown in Figure 1 is composed of two three-way catalysts and three partitions. The exhaust gas flow enters from the inlet of the muffler. After entering, it passes through two three-way catalysts to catalyze the exhaust gas of the engine to meet the emission standard. The direction of the air flow inside the muffler is:

a. First pass through the straight pipe section and U-shaped pipe section in the intake pipe to reach the first chamber. The U-shaped pipe section increases the airflow flow, reduces the airflow pressure and flow rate, and at the same time, the gas turns to make the gas form harmonics in the ventilation channel, effectively reduced noise. The exhaust gas expands in the first chamber, and the sudden cross-section produces reflection or interference of sound waves, which reduces the sound energy radiated outward, hinders the propagation of sound, and plays a role in noise reduction. The straight pipe section of the air intake pipe 25 located in the first chamber is provided with a through hole to better reduce the back pressure of the exhaust system. The straight pipe section of the air inlet pipe 25 is obliquely arranged in the inner cavity of the casing 29, and the end of the straight pipe section connected to the U-shaped pipe section is inclined away from the axis of the casing. Sloped straight tube sections increase air flow even more.

b. The gas flows into the second chamber through the vent hole of the first partition shown in FIG. 2 . The ventilation holes on the first partition allow exhaust gas to enter the adjacent chamber through these through holes, so that the back pressure of the exhaust system can be reduced, the resistance of exhaust gas passing through can be reduced, and the noise reduction effect can be improved at the same time. In this step, the gas undergoes two cross-sectional mutations from a large cross-section (the first chamber) to a small cross-section (vent) and then to a large cross-section (the second chamber), which effectively reduces the exhaust noise. During specific implementation, the holes on the partition for each ventilation pipe to pass through are provided with a guide wall extending along its circumference to the direction in which the ventilation pipe goes out, so that the installation of the ventilation pipe is more firm, and at the same time it also plays a role in guiding the ventilation pipe. Easy to install and install.

c. Through the first ventilation tube, the airflow is introduced into the fourth chamber, during which there may also be two cross-sectional mutations (the second chamber to the first ventilation tube, and then to the fourth chamber) and the insertion catheter (the first snorkel) to reduce exhaust noise. At the same time, the airflow in the second chamber can also be introduced into the third chamber through the vent hole of the first partition as shown in FIG. 3 .

d. Through the second vent tube, the airflow is introduced into the third chamber, during which there may also be two cross-sectional mutations (the fourth chamber to the second vent tube, and then to the third chamber) and the insertion catheter (the second snorkel) to reduce exhaust noise.

e. The gas is discharged through the outlet pipe. In steps c-e, the air flow is from the second chamber to the fourth chamber, and then returns to the third chamber, and finally discharged from the fourth chamber, and the air flow is directly from the second chamber Compared with passing through the third chamber and being discharged from the fourth chamber, the gas in steps c-e has undergone multiple turns, the flow of the airflow is longer, and the noise reduction effect is better. The muffler shown in Figure 1 passes through multiple cycles to finally achieve the purpose of improving the sound quality of the muffler.

The sound-absorbing cylinder also includes a sound-absorbing cylinder fixed in the first chamber 21 and the second chamber 22 and arranged coaxially with the first chamber 21 and the second chamber 22, and the sound-absorbing cylinder is staggered along the circumferential direction of its length direction. There are sound-absorbing holes; sound-absorbing cotton 26 is laid in the gap between the sound-absorbing cylinder and the inner wall of the first chamber and the inner wall of the second chamber. The muffler hole section, the cylindrical shell and the partition form a resistant muffler structure to eliminate the mid-frequency noise in the exhaust system. Sound-absorbing cotton is used for sound absorption to reduce noise. The sound-absorbing cotton can be fixed on the inner wall of the shell by sticking or welding.

The exhaust port of the muffler bends and extends downwards. The tail of the muffler is downward, which reduces the contact surface between the exhaust gas and the air, effectively reduces the chance of abnormal sound caused by re-combustion, and reduces the exhaust noise, and the tail of the outlet pipe is downward, which is conducive to the discharge of water vapor during the discharge process, which helps Anti-rust inside the muffler barrel.

Finally, it is noted that the above embodiments are only used to illustrate the technical solutions of the present invention without limitation. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be carried out Modifications or equivalent replacements without departing from the spirit and scope of the technical solution of the present invention shall be covered by the claims of the present invention.

Claims (5)

1. A muffler for a motorcycle exhaust system, comprising a casing (29), and an air intake pipe (25) and an air outlet pipe (30) arranged in the inner cavity of the casing; its characteristic is that the interior of the casing (29) Two first partitions and one second partition parallel to each other are arranged in sequence in the cavity, and the inner cavity is divided into a first chamber (21), a second chamber (22), a third chamber (23) and In the fourth chamber (24), the first partition is provided with a vent hole (31) for connecting two adjacent chambers; the air inlet pipe includes a straight pipe section and a U-shaped pipe section, and the air inlet end of the straight pipe section The air inlet of the muffler is formed through the front end surface of the shell (29); the air outlet end of the straight pipe section extends from the air inlet of the muffler to the first chamber (21), and at least one three-way catalyst is coaxially arranged in the inner cavity of the straight pipe section One end of the U-shaped pipe section is connected to the gas outlet end of the straight pipe section, and the other end passes from the first chamber (21) through the second chamber (22), and then bends back to the first chamber (21) to be set; it also includes the first The ventilation pipe (27) and the second ventilation pipe (28), the first ventilation pipe (27) extends from the second chamber (22) through the third chamber (23) into the fourth chamber (24); The second ventilation pipe (28) is set from the third chamber (23) through the fourth chamber (24); the outlet pipe (30) passes from the third chamber (23) through the fourth chamber (24) The exhaust port of the muffler is formed by extending out of the rear end face of the casing. 2. The muffler for motorcycle exhaust system according to claim 1, characterized in that the straight tube section of the intake pipe (25) located in the first chamber is provided with a through hole. 3. The muffler of motorcycle exhaust system according to claim 1, characterized in that, the straight pipe section of the intake pipe (25) is arranged obliquely in the inner cavity of the casing (29), and the straight pipe section is in line with the U-shaped One end connected by the pipe section is inclined away from the axis of the casing. 4. The muffler for motorcycle exhaust system according to claim 1, characterized in that it also includes a muffler fixed in the first chamber (21) and the second chamber (22), and the first chamber (21) The sound-absorbing cylinder arranged coaxially with the second chamber (22), the sound-absorbing cylinder is interlaced with sound-absorbing holes along the circumferential direction of its length; the sound-absorbing cylinder is laid in the gap between the inner wall of the first chamber and the inner wall of the second chamber There are sound-absorbing cotton (26). 5 . The muffler for motorcycle exhaust system according to claim 1 , wherein the exhaust port of the muffler bends and extends downward. 6 .