JPH0232811Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an exhaust system particularly suitable for internal combustion engines for vehicles such as automobiles and motorcycles.

[Conventional technology]

The amount of silencing attenuation in an internal combustion engine is closely related to each part of the exhaust system configuration, such as the structure and volume of the muffler, the overall arrangement including the exhaust pipe, and the length and diameter of the exhaust pipe. be.

Particularly in automobiles, vehicles equipped with a rear engine have an extremely short distance from the engine to the end of the exhaust outlet pipe, which requires great effort in designing the exhaust system.

Traditionally, the means to muffle the sound have been to lengthen the overall length of the exhaust pipe by repeatedly bending it in a complicated manner like an octopus, or by maximizing the volume of the muffler. Ta.

There is also a configuration in which the muffling space formed by the partition plates in one muffler is connected by a connecting pipe to make a U-turn in the exhaust gas, but this is not preferable because it reduces the engine output due to an increase in back pressure.

[The problem that the idea aims to solve]

In view of the above points, the present invention aims to simply increase the length of the exhaust pipe in the exhaust system.

[Means to solve the problem]

In the present invention, separately constructed first and second silencers are placed apart from each other, and an exhaust pipe from the first silencer to the second silencer and an exhaust pipe from the second silencer to the first silencer are arranged. Both mufflers are connected through a return and exhaust pipe.

[Effect]

With the above configuration, the exhaust gas from the inlet pipe connected to the manifold is guided to the first muffler to be muffled, then guided to the second muffler via the outgoing exhaust pipe to be muffled, and then passed through the return exhaust pipe to be muffled. Since the exhaust pipe is returned to the first muffler and discharged from the exit pipe after being muffled, an exhaust pipe length twice as long as the interval between the two mufflers can be obtained with an extremely simple configuration, and the amount of sound damping is improved. .

〔Example〕

The illustrated example shows first and second silencers 1 and 2 that are constructed separately, and 3 is an exhaust inlet pipe connected to an engine manifold (not shown), and 4 is an exhaust outlet pipe.

In the example shown in FIG. 1, the exhaust gas from the inlet pipe 3 is guided to the first expanded resonance chamber 5 of the first muffler 1, and the exhaust gas muffled in the chamber 5 is passed through the outgoing exhaust pipe 6 to the first extended resonance chamber of the second muffler 2. The chamber 7 is connected to the adjacent expanded resonance chamber 8 by a pipe 9, and the chamber 8 is connected to the first expansion resonance chamber 7 by a return exhaust pipe 10.
Return to the second expansion resonance chamber 11 of the silencer 1, and the chamber 1
1 to the atmosphere through an outlet pipe 4. That is, the exhaust gas is subjected to two stages of silencing action in the first and second mufflers 1 and 2, respectively.

FIG. 2 shows that the inlet pipe 3 is passed through the first muffler 1 to integrally form the outgoing and exhaust pipe 12, and the second muffler 2
The first extended resonance chamber 13 of the chamber 1 is extended and opened.
3 is communicated with the second extended resonance chamber 15 of the first muffler 1 through a return exhaust pipe 14, and the chamber 15 is connected to the adjacent same chamber 16.
and the chamber 16 is connected to the second exhaust pipe 1 by a pipe 17.
At 8, the second extended resonance chamber 19 of the second muffler 2 is communicated again, and the chamber 19 is discharged through the outlet pipe 4.
In this example, the inlet pipe 3 is opened to the first chamber 20 of the first muffler 1 through a small hole 21, and the first chamber 20 is used as an interference muffling chamber. In this modified sequence, the first and second
An exhaust pipe length that is three times the distance between the silencers is obtained.

FIG. 3 shows that the inlet pipe 3 and outlet pipe 4 are extended to the second muffler 2 through two adjacent interference muffling chambers 21 and 22 of the first muffler 1, and the outgoing exhaust pipe 23 and return exhaust pipe 24 are integrated. The outgoing exhaust pipe 23 is connected to the first extended resonance chamber 13 of the second muffler 2, and the return exhaust pipe 24 is connected to the second extended resonance chamber 13 of the second muffler 2.
The second expansion resonance chamber 19 of the muffler 2 is opened, the two chambers 13 and 19 are connected by a coupling pipe 25, and both the exhaust pipes 23 and 24 are connected to the small holes 26 to 28 for two interference silencing of the first muffler 1. Room 21, 22 or 1 room 2
This configuration is connected to 2.

The embodiment shown in FIG. 4 shows a first muffler 1 and a second muffler 2.
The forward and backward exhaust pipes 31 and 33 that communicate with each other are fitted inside and out to form a double pipe. That is, the first chamber 30 into which the inlet pipe 3 of the first muffler 1 opens
The outer pipe 31 of the double pipe is used as an outgoing exhaust pipe and opens into the first chamber 32 of the second muffler 2, and the inner pipe 33 of the double pipe is used as a return exhaust pipe and opens into the second chamber 34 of the second muffler 2. 1st
It communicates with the second chamber 35 of the muffler 1, and the second chamber 35 is provided with an outlet pipe 4.

However, the internal structure of each of the mufflers 1 and 2 can be appropriately combined with expansion, interference, resonance, and absorption muffling elements in addition to the illustrated example.

[Effect of idea]

As described above, by communicating the silencers that are arranged separately through the outgoing exhaust pipe and the return exhaust pipe, the exhaust pipe length can be increased to twice the distance between the two silencers without increasing back pressure. This improves the silencing performance. In addition, flexibility is gained in the relative positioning of the silencers, making the layout of the exhaust system easier.
Even in the case of the above-mentioned rear engine vehicle, there are effects such as the simplification of the exhaust system.

[Brief explanation of the drawing]

1 to 4 are schematic diagrams showing an embodiment of the exhaust system of the present invention. 1 and 2 are first and second mufflers, 3 and 4 are exhaust inlet and outlet pipes, 6, 12, 18, 23, and 31 are outgoing exhaust pipes from the first muffler to the second muffler, 10,
14, 24, and 33 are return and exhaust pipes from the second muffler to the first muffler.

Claims (1)

[Scope of utility model registration request] The first and second silencers, each constructed separately, are placed apart from each other, and after the exhaust gas from the inlet pipe is guided to the first silencer and silenced, the outgoing exhaust pipe provided between the two silencers is connected to the first and second silencers. The air is introduced into the second muffler through the muffler to muffle the sound, and is returned to the first muffler through the return and exhaust pipe provided between the two mufflers to muffle the sound. An exhaust system for an internal combustion engine, characterized in that an exhaust pipe length is twice as long as the distance between the arrangement intervals.