KR100525766B1 - Front muffler - Google Patents

Abstract

The present invention relates to a front muffler,

A front muffler which exhaust gas is composed of a plurality of inner pipes communicating with the exhaust manifold of the internal combustion engine, a communicating member for communicating the inner pipes as one, and an outer plate forming an air gap on the outside of the inner pipe and the communicating member. In the communication member is made of a Y-shaped plate 23, the partition wall in the interior, the Y-shaped plate 23 is a front end portion is coupled to the plurality of inner pipes 22 to communicate with one at the rear end The first Y-shaped plate 23a on the upper side and the second Y-shaped plate 23b on the lower side are coupled to each other, and the partition wall is formed on the first side of the first Y-shaped plate 23a. The partition 24a and the 2nd partition 24b extended in the inside of the 2nd Y-shaped plate 23b are provided, It is characterized by the above-mentioned.

In order to keep the exhaust gas discharged from the exhaust manifold, an air gap is formed in the front muffler to shorten the activation time of the catalyst system, and a partition wall in the front muffler improves engine noise and improves engine output. do.

Description

Front muffler {Front muffler}

The present invention relates to a front muffler, and more particularly, a front muffler connected between an exhaust manifold and a catalytic device of an internal combustion engine to heat the exhaust pipe exhausted from the exhaust manifold. The present invention relates to a front muffler which forms an air gap on the Y-type plate to shorten the activation time of the catalytic device, and installs a partition wall on the Y-type plate to improve engine noise and improve engine output.

The exhaust system of the internal combustion engine, that is, the muffler is installed in the lower part of the vehicle body, and harmful components of the high-temperature and high-pressure exhaust gases discharged through the exhaust manifold when the engine is burned, such as automobiles, HC, CO, It is a device that converts NO _x and the like into CO ₂ , H ₂ O, which are harmless gases by promoting the chemical reaction of the catalyst, and discharges them to the outside.

Recently, the regulation of automobile exhaust gas, which is one of the main causes of air pollution, is gradually being tightened. Therefore, not only the installation of the exhaust system is mandatory, but research on this is being actively conducted.

Normally, the muffler consists of a front muffler, a catalytic device, a center muffler and a main muffler. The exhaust from the internal combustion engine is discharged to the front muffler through an exhaust manifold, and flows in the order of the catalytic device, center muffler and main muffler. To be discharged.

The exhaust manifold is the first place where the mixer explodes in the engine and exhausts from the cylinder, gathering exhaust gases from multiple cylinders in one place.

In order to collect the exhaust in one place, one thing to think about is that the engine that goes back to the intake, compression, explosion, and exhaust stroke will explode in the order of cylinders 1 to 3 to 4 and 2 to 2 cylinders. 3 after 4 times, 2 releases the exhaust gas, but the exhaust valve opens before the piston fully lowers.

Therefore, before the exhaust stroke of cylinder 1 is finished, the exhaust stroke of cylinder 3 starts, and if the exhaust gas from cylinders 1 and 3 is connected immediately, while the exhaust valve is briefly opened during the intake stroke of cylinder 1, The exhaust gas of cylinder 3 flows back to cylinder 1. In other words, if the exhaust gas flows out of two connected cylinders at once, the exhaust pipe is relatively narrowed. This phenomenon is called exhaust gas interference.

Therefore, exhaust gases from several cylinders must be sent to the exhaust pipe in order, so exhaust manifolds 1, 4, 3 and 2 are gathered first, and these two passages are gathered together at the rear end of the front muffler. The 4-2-1 method is called the 4-1 method, and the 4-2-1 method is used for high speed and the 4-1 method is used for driving on a general road.

Ideally, exhaust pipes should be made out of each exhaust port to be exhausted without any interference at all, but they are expensive, weighty, and impractical to use. The difference is that the exhaust from the long cylinder of the manifold will have to meet with the gas from the short manifold, which will also lead to bait.

The core of the exhaust system is to design a similar length to reduce the interference, and the exhaust system that generates the exhaust consumes the power of the engine to release the gas, and as a result, there is a problem of lowering the output of the engine.

In addition, the temperature of the exhaust gas which just exited the cylinder through the exhaust valve is about 1000 ° C, but it is cooled by passing through the exhaust system, and the exhaust port where the coolant and the engine oil cool down (head side port where the cylinder head and exhaust manifold meet). The temperature of the exhaust gas is lowered while the temperature is lowered, and the temperature of the exhaust gas body is lowered when heat exits the front muffler cooled by the outside air when it exits the front muffler. In other words, when the temperature of the gas is lowered, the volume is reduced, in other words, the weight is heavy even in the same volume, the heavy exhaust gas has a problem that the operation is slowed.

Since the exhaust is cooled, the activation time of the catalyst for purifying the exhaust gas is delayed, causing excessive smoke at the initial start of the engine.

In addition, there is a problem in that the output of the engine is lowered and noise is generated due to the interference of the exhaust when combined in one in the two exhaust passages.

The present invention has been made to solve the above-mentioned conventional problems, to form an air gap in the front muffler to insulate the exhaust gas discharged from the exhaust manifold to shorten the activation time of the catalyst device, the partition wall on the front muffler It is an object of the present invention to provide a front muffler that improves engine noise and improves engine power by incorporating the engine.

The present invention for achieving the above object, a plurality of internal pipes to communicate with the exhaust manifold of the internal combustion engine, a communication member for communicating the internal pipes in one, and forming an air gap on the outside of the internal pipe and the communication member In the front muffler consisting of an outer plate for discharging the exhaust gas, the communication member is composed of a Y-shaped plate 23 with a partition built therein, the Y-shaped plate 23 has a front end portion of the plurality of inner pipes (22) is coupled to communicate with one at the rear end, the upper first Y-shaped plate (23a) and the lower second Y-shaped plate (23b) is made of a combination, the partition wall is the first Y The first partition 24a extended in the inner side of the mold plate 23a and the second partition 24b extended in the inner side of the second Y-shaped plate 23b are preferably provided. Invention is above The first partition 24a and the second partition 24b are spaced apart at predetermined intervals.

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Preferably, the present invention is characterized in that the partition wall holes 25a, 25b are perforated at the rear end of the partition wall.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

1 is a perspective view schematically showing a front muffler according to an embodiment of the present invention, Figure 2 is a partial cutaway view schematically showing a front muffler according to an embodiment of the present invention, Figure 3 is an embodiment of the present invention 4 is a configuration diagram schematically showing a Y-shaped plate of the front muffler, FIG. 4 is a schematic cross-sectional view schematically showing a Y-shaped plate of the front muffler according to an embodiment of the present invention, and FIG. 5 is a cut line of FIG. 4. 6 is a cross-sectional view taken along the cutting line BB of FIG. 4, FIG. 7 is a graph showing a comparison between the front muffler according to an embodiment of the present invention and the discharge noise of the conventional invention, and FIG. A graph showing a comparison between the front muffler according to an embodiment of the present invention and the engine output of the conventional invention.

As shown in Fig. 1 and Fig. 2, the front muffler of this embodiment is disposed at the tip of the muffler which is an exhaust device, and an exhaust manifold (not shown) for exhausting the exhaust from the engine and a catalytic device (not shown) for purifying the exhaust. It is the front muffler in which the air gap was formed in the front muffler installed between and. The front muffler is composed of an inner pipe 22, a Y-shaped plate 23, an outer plate 20, a bellows 30, and a rear pipe 40 as communication members.

The inner pipe 22 is composed of two pipes forming an exhaust outlet, and the front end portion communicates with the exhaust manifold via the front flange 10 to form an outlet through which the exhaust of the internal combustion engine is discharged.

The Y-shaped plate 23 is formed in a Y shape in which the front end portion is divided into two through holes by the partition wall and the through holes are joined at the rear end portion. The two inner pipes 22 are fitted and welded to the two through-holes of the front end and communicate with each other at the rear end. In addition, the Y-shaped plate 23 is the second Y-type, which is the lower plate on which the first Y-shaped plate 23a and the second partition 24b are welded, the upper plate on which the first partition 24a is welded. The plates 23b are fitted to each other on the upper and lower sides and welded together.

The outer plate 20 is welded to the upper and lower parts of the inner pipe 22 and the Y-shaped plate 23 through the steel wire mat 21 through the outer circumference of the inner pipe 22 and the Y-shaped. An air gap is formed around the outer circumference of the plate 23. Steel wire mat 21 is formed in the form of a mesh structure in which a metal wire is tightly woven like a net so as to secure the air gap. In the present embodiment, the steel wire mat 21 is installed in the front part of the inner pipe 22 and the connection part of the inner pipe 22 and the Y-shaped plate 23, but the present invention is not limited thereto. It may be in multiple locations for

The bellows 30 has steel wires braided on the outside of the cylindrical corrugated pipe and caps are assembled at both ends, thereby absorbing vibration generated from the engine exhaust system and reducing noise. It absorbs and improves ride comfort, and greatly improves the endurance life of the exhaust system, so that it is welded to fit the distal end of the Y-shaped plate 23. Thus, vibrations or shocks transmitted to the muffler are alleviated.

The rear pipe 40 is welded by fitting to the distal end of the bellows 30 to discharge the exhaust to the rear, and a support hanger 41 for mounting the front muffler to the side of the vehicle body is mounted on the side, and the rear end is rearward. The flange 50 is welded together. The rear flange 50 is fitted with studs 51 for engagement with a catalytic device (not shown) on both sides.

As shown in Figs. 3 and 4, in the Y-shaped plate 23, the first partition wall 24a is welded inside the first Y-shaped plate 23a so that the upper partition wall extends, and the second The second partition 24b is welded inside the Y-shaped plate 23b to extend the lower partition. Accordingly, the exhaust gas discharged from the two inner pipes 22 rapidly merges in the Y-shaped plate 23 and gradually merges with the partitions 24a and 24b without causing any interruption, thereby preventing a decrease in output due to the interruption. You can do it.

 The rear end portions of the partition walls 24a and 24b have a predetermined size of the first partition hole 25a and the second partition wall hole so as to prevent the partition walls 24a and 24b from deteriorating due to the rapid merging of the exhaust and to gradually induce the confluence. It is preferable to puncture a plurality of (25b).

Moreover, it is preferable that the said 1st partition 24a and the 2nd partition 24b are spaced at predetermined intervals so that exhaust gas may gradually merge along partitions 24a and 24b. When the distance between the first partition 24a and the second partition 24b is smaller than 1 mm, the effect of low medium speed torque and output improvement is less. When larger than 3 mm, the effect of low medium speed torque and output enhancement is hardly exhibited. Therefore, it is more preferable to apply predetermined intervals to 1-3 mm.

The manufacturing method of the outer plate 20 and the Y-type plate 23 is demonstrated based on FIG. 5 and FIG. 6 as sectional drawing cut along the cutting lines A-A and B-B of FIG.

In the present embodiment, the Y-shaped plate 23 is welded to the middle portion of the first Y-shaped plate 23a by welding the partition-shaped first partition wall 24a having the first partition wall hole 25a bored therein. Similarly, the second partition wall 24b of the partition bar shape in which the second partition wall hole 25b is drilled at the rear end is also welded and bonded to the middle portion of the second Y-shaped plate 23b.

In addition, the first partition wall 24a is bent in one direction so as to secure a contact surface with the first Y-shaped plate 23a at the time of welding engagement with the first Y-shaped plate 23a. Is formed. The second partition 24b is also formed in the same shape as the first partition 24a.

The first Y-shaped plate 23a and the second Y-shaped plate 23b, to which the partition walls are welded, are fitted and welded to each other from above and below to form the Y-shaped plate 23. The two inner pipes 22 are fitted to the distal ends of the coalesced Y-shaped plate 23 to perform welding. Therefore, the exhaust gas having passed through the two inner pipes 22 gradually merges into one without passing through the Y-shaped plate 23.

Various welding methods are possible for the welding operation, but for example, it is preferable to use a MIG welding method using a welding wire.

After the steel wire mat 21 is welded to the inside of the upper and lower parts of the outer plate 20 as a reinforcing material to form an air gap around the inner pipe 22 and the Y-shaped plate 23 that are integrally welded together. The upper and lower parts of the outer plate 20 are fitted to be assembled so as to surround the inner pipe 22 and the Y-shaped plate 23. The front end is fitted to the front flange 10 and the rear end is bellows 30. The main part of the front muffler is completed by welding each fitting portion by fitting in the. The front muffler is completed by joining and welding the rear pipe 40 and the rear flange 50 thereto. At this time, it is preferable to use spot welding, which is a spot welding method, for example, as the welding coupling between the outer plate 20 and the steel wire mat 21.

As shown in Fig. 7, the result of measuring the discharge noise according to the rotational speed of the engine in the case where the front muffler is present in the front muffler and in the absence of the partition is shown as a graph. Compared with the discharge noise, the discharge noise is almost no difference in the high speed section, but the discharge noise in the middle and low speed sections is decreased by about 1 ~ 3㏈ compared to the case without the partition, and the airflow noise is also reduced. .

As shown in Fig. 8, the result of measuring torque according to the engine speed in the case where the front muffler is present in the front muffler and in the absence of the partition is shown as a graph. Comparing the torque of, the torque of the high speed section shows little difference, but the torque of the bulkhead in the middle and low speed section is increased by about 2 ~ 6% than the case of the absence of the bulkhead, and the engine output is improved.

The present invention described above can be embodied in many other forms without departing from the spirit or main features thereof. Therefore, the above embodiments are merely examples in all respects and should not be interpreted limitedly.

As described above, the present invention forms an air gap in the front muffler to shorten the activation time of the catalyst device to insulate the exhaust gas discharged from the exhaust manifold, improves engine noise by installing a partition wall in the front muffler. It provides an effect of improving the output of the engine. Furthermore, the upper and lower partitions are spaced at predetermined intervals to provide an effect of improving torque and output of the engine at low and medium speeds. There is an effect of preventing the deterioration of the partition wall caused by the rapid confluence of exhaust by puncturing, and inducing confluence gradually.

1 is a perspective view schematically showing a front muffler according to an embodiment of the present invention.

2 is a partial cutaway view schematically showing a front muffler according to an embodiment of the present invention.

Figure 3 is a schematic diagram showing a Y-shaped plate of the front muffler according to an embodiment of the present invention.

Figure 4 is a schematic cross-sectional view showing a Y-shaped plate of the front muffler according to an embodiment of the present invention.

5 is a cross-sectional view taken along the line A-A of FIG. 4.

6 is a cross-sectional view taken along the line B-B of FIG. 4.

7 is a graph showing a comparison between the front muffler and the discharge noise of the conventional invention according to an embodiment of the present invention.

8 is a graph showing a comparison between the front muffler according to an embodiment of the present invention and the engine output of the conventional invention.

<Description of the symbols for the main parts of the drawings>

10: front flange 20: outer plate

21: steel wire mat 22: inner pipe

23: Y type plate 23a: 1st Y type plate

23b: 2nd Y plate 24a: 1st partition

24b: 2nd partition 25a: 1st partition hole

25b: second bulkhead hole 30: bellows

40: rear pipe 41: support hanger

50: rear flange 51: stud

Claims (3)

A front muffler which exhaust gas is composed of a plurality of inner pipes communicating with the exhaust manifold of the internal combustion engine, a communicating member for communicating the inner pipes as one, and an outer plate forming an air gap on the outside of the inner pipe and the communicating member. To The communication member is made of a Y-shaped plate 23, the partition wall is built in, The Y-shaped plate 23 has a front end coupled to the plurality of inner pipes 22 to communicate with each other at a rear end thereof, and the first Y-shaped plate 23a on the upper side and the second Y-shaped plate 23b on the lower side. ) Are combined, The partition wall includes a first partition wall 24a extending inside the first Y-shaped plate 23a and a second partition wall 24b extending inside the second Y-shaped plate 23b. The front scarf characterized by. The method of claim 1, The front muffler, wherein the first partition wall 24a and the second partition wall 24b are spaced at a predetermined interval. The method according to claim 1 or 2, The front muffler, characterized in that the partition wall holes (25a, 25b) are perforated at the rear end of the partition wall.