JP4528564B2 - Muffler for internal combustion engine - Google Patents

Description

  The present invention relates to a muffler for an internal combustion engine mounted on an exhaust system of an automobile.

Conventionally, a muffler for an internal combustion engine is provided in an exhaust system of an automobile. As disclosed in Patent Documents 1 and 2, the internal combustion engine muffler covers the outer periphery with a shell member and partitions the inside of the shell member with a plurality of partition plates to form an expansion chamber, a resonance chamber, and the like. While exhaust was led inside, exhaust was led outside by the exit pipe.
Japanese Patent Laid-Open No. 2003-3820 JP 2003-138935 A

  However, in such a conventional one, a plurality of partition plates must be provided in order to partition the inside of the shell member, and an inlet pipe and an outlet pipe for guiding exhaust gas must be provided, resulting in a large number of parts and a heavy weight. In addition, there is a problem that assembly is complicated.

  An object of the present invention is to provide a muffler for an internal combustion engine that has few parts and can be easily assembled.

In order to achieve this problem, the present invention has taken the following measures in order to solve the problem. That is,
In an internal combustion engine muffler comprising an inlet pipe that guides exhaust to the inside and an outlet pipe that guides exhaust to the outside, the outer periphery of which is formed by a shell member.
The shell member is formed flat and the inlet pipe is inserted until it abuts against the opposite side wall, and the shell member is brought into contact with both sides of the outer periphery of the inlet pipe, and the inside of the shell member is formed by the inlet pipe. This is a muffler for an internal combustion engine characterized by partitioning a resonance chamber and an expansion chamber .

The outlet pipe may be inserted to the vicinity of the opposite side wall inside the shell member, and the shell member may be in contact with both outer peripheral sides of the outlet pipe . Further, the shell member may be formed by overlapping an upper shell member and a lower shell member, and the shell member may be press-molded.

In the muffler for an internal combustion engine of the present invention , the shell member is brought into contact with both sides of the outer periphery of the inlet pipe, and the inside of the shell member is partitioned by the inlet pipe to form the resonance chamber and the expansion chamber , thereby reducing the number of parts and reducing the weight. This also has the effect of facilitating assembly.

The best mode for carrying out the present invention will be described below in detail with reference to the drawings.
As shown in FIG. 1, reference numeral 1 denotes an internal combustion engine muffler. The internal combustion engine muffler 1 has a so-called outermost structure in which an upper shell member 2 and a lower shell member 4 are overlapped and an outer periphery is formed by a shell member 6. Medium structure.

  In the present embodiment, the upper shell member 2 and the lower shell member 4 are formed by press forming by drawing. The upper shell member 2 and the lower shell member 4 are formed by press forming, leaving flat edges 2a, 4a in the periphery and being recessed, and the edges 2a, 4a are butted together to overlap the shell member 6 A chamber is formed inside.

  The shell member 6 is formed in a flat rectangular parallelepiped shape, and the upper and lower surfaces of the flat shell member 6 are formed in a corrugated curved surface. In the present embodiment, a large number of small ribs 2b and 4b are formed over the entire surface of the corrugated curved surface, but the ribs 2b and 4b may be provided as necessary.

  The shell member 6 is provided with an inlet pipe 8 and an outlet pipe 10 that are open at one end side in the opposite direction. As shown in FIGS. 3 and 4, the upper shell member 2 and the lower shell member 4 are in direct contact with the inlet pipe 8 on both sides of the outer periphery thereof, and the inlet pipe 8 is inserted into the shell member 6. Yes.

  The inlet pipe 8 is opened to one side wall side of the shell member 6 and is abutted against the opposite side wall. The inside of the shell member 6 is divided into the resonance chamber 12 and the expansion chamber 14 by the inlet pipe 8. It is partitioned. The outer periphery of the inlet pipe 8 and the upper shell member 2 and the lower shell member 4 are joined by welding or the like, and the resonance chamber 12 is formed in a sealed state.

  Half of the outer periphery of the inlet pipe 8 faces the resonance chamber 12 and the other half faces the expansion chamber 14. A through hole 16 is formed in the outer periphery of the inlet pipe 8 facing the resonance chamber 12, and a passage member 18 having a U-shaped cross section is formed in the outer periphery of the inlet pipe 8 so as to cover the through hole 16. Is attached. A large number of small holes 20 are formed in the outer periphery of the inlet pipe 8 facing the expansion chamber 14.

In this way, the inlet pipe 8 is abutted against the opposite side wall and partitioned into the resonance chamber 12 and the expansion chamber 14 .

  The outlet pipe 10 is disposed in parallel with the inlet pipe 8, and the upper shell member 2 and the lower shell member 4 are in direct contact with the outlet pipe 10 on both sides of the outer periphery thereof. The outlet pipe 10 is inserted into the shell member 6 from the opposite direction to the inlet pipe 8, and is inserted to the vicinity of the opposite side wall. A space is provided between the end of the outlet pipe 10 in the expansion chamber 14 and the opposite side wall of the shell member 6 so that the exhaust gas in the expansion chamber 14 can flow into the outlet pipe 10. . The outer periphery of the outlet pipe 10 and the upper shell member 2 and the lower shell member 4 are joined by welding or the like.

In the present embodiment, the shell member 6 is brought into contact with both outer peripheral sides of the inlet pipe 8 and the outlet pipe 10. However, the present invention is not limited thereto, and the shell member 6 is brought into contact only with the outer circumference of the inlet pipe 8. But it is possible. Moreover, you may make it provide a partition board in the inside of the shell member 6 as needed.

Next, the operation of the muffler for the internal combustion engine of the present embodiment described above will be described.
When exhaust gas from an internal combustion engine (not shown) is guided to the inlet pipe 8, exhaust noise of a specific frequency is reduced by the resonance effect of the Helmholtz resonator formed by the passage member 18 and the resonance chamber 12. Further, when the exhaust gas is guided to the expansion chamber 14 from a large number of small holes 20 in the inlet pipe 8, high frequency exhaust noise is reduced due to the expansion effect and the interference effect. The exhaust in the expansion chamber 14 is guided from the outlet pipe 10 to the external downstream exhaust pipe.

  Thus, since the inside of the shell member 6 is partitioned into the resonance chamber 12 and the expansion chamber 14 by the inlet pipe 8, the inlet pipe 8 can be provided without providing a partition plate or the like for partitioning the inside of the shell member 6. Since it can partition using, the number of parts can be reduced. Further, since the inlet pipe 8 and the outlet pipe 10 are in contact with and joined to the shell member 6, it functions as a reinforcing member for the flat shell member 6, and there is no need to separately provide a partition plate or the like for reinforcement. Also in this respect, the number of parts can be reduced.

  Moreover, since it is not necessary to provide a partition plate etc., assembly work becomes easy. Furthermore, since the shell member 6 can be formed from the press-formed upper shell member 2 and the lower shell member 4, the shell member 6 can be easily formed.

  The present invention is not limited to such embodiments as described above, and can be implemented in various modes without departing from the gist of the present invention.

It is a perspective view of the muffler for internal combustion engines as one embodiment of the present invention. It is an enlarged plan view of the muffler for the internal combustion engine of the present embodiment. It is the enlarged plan view which removed the upper shell member of the muffler for internal combustion engines of this embodiment. It is AA sectional drawing of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine muffler 2 ... Upper shell member 4 ... Lower shell member 6 ... Shell member 8 ... Inlet pipe 10 ... Outlet pipe 12 ... Resonance chamber 14 ... Expansion chamber 16 ... Through-hole 18 ... Passage member 20 ... Small hole

Claims (4)

In an internal combustion engine muffler comprising an inlet pipe that guides exhaust to the inside and an outlet pipe that guides exhaust to the outside, the outer periphery of which is formed by a shell member.
The shell member is formed flat and the inlet pipe is inserted until it abuts against the opposite side wall, and the shell member is brought into contact with both sides of the outer periphery of the inlet pipe, and the inside of the shell member is formed by the inlet pipe. A muffler for an internal combustion engine, wherein a resonance chamber and an expansion chamber are formed by partitioning . 2. The internal combustion engine according to claim 1, wherein the outlet pipe is inserted to reach the vicinity of an opposite side wall inside the shell member, and the shell member is brought into contact with both outer peripheral sides of the outlet pipe. Muffler. The shell member is an internal combustion engine muffler according to claim 1 or claim 2, characterized in that formed by superposing the upper shell member and the lower shell member. The shell member is an internal combustion engine muffler according to any one of claims 1 to claim 3, characterized in that the pressed molding.

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