JP2009092032A - Silencer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a muffler connected to an exhaust system in an engine which requires no reaming work after supporting an exhaust pipe to a partition plate and no separate formation of a flare pipe, and achieves the reduction in manufacturing cost and improvement of productivity. <P>SOLUTION: A straight outlet pipe 20 containing reaming parts 20A, 20B in both ends is fitted and supported to a partition plate 3 for partitioning the inside of a shell 2 into a plurality of muffler chambers 4, 5. An expansion part 20C having a diameter equal to or larger than those of the reaming parts 20A, 20B is formed between the reaming parts 20A, 20B. The outlet pipe 20 is fitted and supported to the partition plate 3 in the expansion part 20C. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a silencer connected to an exhaust system of an engine, and more particularly to a silencer with improved productivity.

Conventionally, in the silencer, a partition plate for partitioning the inside of the shell forming the outer shell into a plurality of silencer chambers is provided, and an exhaust pipe such as an outlet pipe through which exhaust gas flows is fitted and supported on the partition plate, An exhaust pipe is provided at least at one end of the exhaust pipe so that exhaust gas can easily flow into the exhaust pipe or exhaust gas flowing through the exhaust pipe can be easily discharged (for example, Patent Documents described later) 1 and 2).
Japanese Patent No. 3934818 Japanese Patent No. 3934818

  However, in the silencer, the exhaust pipe such as an outlet pipe is fitted and supported on the partition plate, and then the pipe end of the exhaust pipe is expanded, and in this case, the partition plate is disposed around the exhaust pipe. Since there are parts other than the exhaust pipe, etc., the workability of the expansion process is poor, and if this is to be solved, the silencer can be designed such that the partition plate spacing is increased beyond the originally required spacing. There is a problem with creating constraints.

  In order to solve this problem, as disclosed in Japanese Patent Application Laid-Open No. 2006-9609, a flare pipe having an enlarged opening formed separately is connected to the opening end of the exhaust pipe, and a partition plate, an exhaust Proposal is made to eliminate the need to expand the exhaust pipe with the partition plate by simultaneously welding the pipe and flare pipe to support the exhaust pipe and the flare pipe on the partition plate. Has been.

  However, the one disclosed in Japanese Patent Application Laid-Open No. 2006-9609 has another problem that not only the number of parts increases but also the welding work becomes troublesome because the flare pipe is formed separately.

  The present invention eliminates the need for the expansion process after fitting and supporting the exhaust pipe to the partition plate, and does not require the flare pipe to be formed separately, thereby reducing the number of parts and improving the productivity. The purpose is to provide a new silencer that solves all the problems.

In order to achieve the above-mentioned object, the invention of claim 1 is a silencer that fits and supports a straight pipe exhaust pipe having expanded portions at both ends to a partition plate that partitions a shell into a plurality of silencer chambers. ,
An expansion portion having a diameter equal to or larger than that of at least one expansion portion is formed between the expansion portions at both ends of the exhaust pipe, and the exhaust pipe is fitted and supported on the partition plate by the expansion portion. .

In order to achieve the above object, the invention according to claim 2 is a silencer that fits and supports an exhaust pipe to a partition plate that partitions the inside of the shell into a plurality of silencer chambers.
The exhaust pipe is composed of a straight pipe having an expanded portion at one end and a bent pipe connected to the straight pipe, and an expansion portion having a diameter equal to or larger than that of the expanded portion is formed in an intermediate portion of the straight pipe. In this expansion part, the exhaust pipe is fitted and supported by the partition plate.

  According to the invention described in each claim, in the exhaust pipe formed with the expansion portion and the expansion portion having a diameter equal to or larger than the expansion portion, the exhaust pipe is fitted to the partition plate from the expansion portion side. Since the exhaust pipe is inserted into the hole and fitted to the partition plate at the expansion part, expansion processing after the exhaust pipe is supported by the partition plate becomes unnecessary, and the flare pipe needs to be formed separately. As a result, the number of parts does not increase. Therefore, the manufacturing cost can be reduced and the productivity can be improved. Furthermore, since the expansion part forms a sound deadening chamber, exhaust noise can be further reduced.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below based on examples of the present invention shown in the accompanying drawings.

  In this embodiment, the silencer of the present invention is applied to an exhaust system of an automobile engine. FIGS. 1 to 7 show the first embodiment of the present invention, and FIG. 2 is a schematic side view of an exhaust system of an engine equipped with a device, FIG. 2 is a perspective view of a silencer as viewed in the direction of arrow 2 in FIG. 1, FIG. 3 is a sectional view taken along line 3-3 in FIG. 3 is a cross-sectional view taken along the line 4-4 in FIG. 3, FIG. 5 is a cross-sectional view taken along the line 5-5 in FIG. 4, FIG. 6 is a cross-sectional view taken along the line 6-6 in FIG. It is a figure which shows how to assemble.

  In FIG. 1, an exhaust system Ex for exhausting exhaust gas exhausted by its operation to the atmosphere is connected to an automobile engine generally indicated by E, and this exhaust system Ex is connected to the engine E. The exhaust gas exhaust pipe 1 connected to the exhaust port is connected to the catalyst C and the pre-chamber P from the upstream side to the downstream side, and the exhaust gas introduction is connected to the inlet of the silencer M on the downstream side of the exhaust gas exhaust pipe 1. The pipe 1E is connected through a joint J.

  When the exhaust system Ex is connected to the engine E, the shell 2 of the silencer M is disposed in a forward inclined posture with an inclination angle θ with respect to a horizontal plane.

  The exhaust gas exhausted from the engine E is purified from harmful components such as HC and NOx by the catalyst C, is primarily silenced by the pre-chamber P, and is secondarily silenced by the silencer M to be released into the atmosphere. Discharged.

  Next, the structure of the silencer M according to the present invention will be described in detail with reference to FIGS.

  The shell 2 constituting the outer shell of the silencer M is formed by winding a stainless steel plate into a cylindrical shape and integrally joining both ends of the shell, and the right and left open ends are airtight. Before being caulked and fixed, the rear end plates 2b and 2c are formed in a sealed state. As shown in FIGS. 2 and 3, the longitudinal shape of the hermetic shell 2 is such that the lower half of the sealed shell 2 has a gently convex curved surface with the lower half facing downward and the upper half with the lower half facing upward. The shell 2 is formed into a substantially curved surface that is steeper than the portion, and has a substantially elliptical shape, and the shell 2 is connected to the downstream portion of the exhaust gas discharge pipe 1 with its short diameter side facing up and down. An exhaust gas introduction pipe 1E connected to the exhaust gas discharge pipe 1 and a tail pipe 30 opened to the atmosphere are both connected to the front end plate 2b of the shell 2 in an airtight manner. It bypasses one side of 2 and extends backward.

  As shown in FIGS. 4 and 6, the noise reduction chamber defined in the shell 2 is partitioned into first and second noise reduction chambers 4 and 5 by a partition plate 3. As will be described in detail later, the partition plate 3 is press-fitted and fixed (not welded) in an airtight manner to the inner periphery of the shell body 2a of the shell 2, and the first partition plate 3 and the front end plate 2b are connected to each other. A silencing chamber 4 is formed, and a second silencing chamber 5 is formed between the partition plate 3 and the rear end plate 2c. The partition plate 3 is provided with a number of communication holes 6 made of punching holes except for the fitting support portions of the inlet pipe 10 and the outlet pipe 20 described later and the outer peripheral portion thereof. The first and second silencing chambers 4 and 5 communicate with each other. In addition, the partition plate 3 is formed with a bulging surface 3A that bulges slightly toward the second silencing chamber 4 side.

  As shown in FIGS. 4 to 6, the outer periphery of the partition plate 3 is formed with a flange-like press-fitting portion 3 </ b> B that is bent substantially perpendicularly from the radial direction thereof, and the outer periphery of the partition plate 3 has a press-fitting jig F. A plurality of recesses 7 that can be engaged with the protrusions p (see FIG. 5) are formed. The press-fitting portion 3B on the outer periphery of the partition plate 3 is press-fitted and fixed (not welded) with the press-fitting jig F to the inner periphery of the shell body 2a. The

  As shown in FIGS. 2 to 4, the front end (upstream end) of the inlet pipe 10 disposed in the shell 2 is connected to the rear end (downstream end) of the exhaust gas introduction pipe 1 </ b> E. 2a, the rear end of the exhaust gas introduction pipe 1E and the front end of the inlet pipe 10 are welded simultaneously in an airtight manner. The inlet pipe 10 is formed in a straight shape over the entire length thereof and extends in the longitudinal direction in the first silencing chamber 4 in the shell 2, and a rear end (downstream end) of the guide portion 8 is formed to bulge in the partition plate 3. It is fitted and supported by and welded to it. A large number of discharge holes 12 are formed on the outer peripheral surface of the inlet pipe 10, and the inside of the inlet pipe 10 is also communicated with the first silencer chamber 4 through these discharge holes 12.

  As shown in FIG. 4, most of the exhaust gas flowing into the inlet pipe 10 from the exhaust gas introduction pipe 1E flows into the second silencing chamber 5 from the rear end opening, and a part of the exhaust gas flows into the numerous exhaust holes. 12 flows into the first silencing chamber 4 and then flows into the second silencing chamber 5 through a number of communication holes 6 drilled in the partition plate 3. In this process, the exhaust sound is attenuated by the expansion of the exhaust gas, and the exhaust sound is silenced. And the exhaust gas which flowed into the 2nd silencer chamber 5 flows in into the outlet pipe 20 mentioned later.

  As shown in FIGS. 4 to 6, an outlet pipe 20 is disposed in parallel with the inlet pipe 10 at the bottom of the shell 2. The outlet pipe 20 is formed in a straight shape and extends in the front-rear direction in the shell 2 across the first and second silencing chambers 4 and 5, and as will be described in detail later, an intermediate portion thereof. The expansion portion 20C is fitted and supported in a fitting hole 9 formed in the bottom of the partition plate 3, and its front end (downstream end) is fitted and supported on the front end plate 2b. The rear end (upstream end) of the outlet pipe 20 is formed in a divergent widened portion 20B and is opened in the second silencing chamber 5, so that the exhaust gas in the second silencing chamber 5 can easily flow in. Has been. Further, the front end (downstream end) of the outlet pipe 20 is also formed in another widened portion 20A that is widened to substantially the same diameter, and is connected to the tail pipe 30 through the front end plate 2b. Both the front end (downstream end) of the pipe 20 and the tail pipe 30 are hermetically and simultaneously welded to the front end plate 2b. An expansion portion 20C that expands in the radial direction is formed between the expanded portions 20A and 20B at both ends of the outlet pipe 20, that is, in the middle portion of the outlet pipe 20, and the front and rear of the expansion portion 20 are formed on tapered surfaces. The pipe 20 is smoothly connected. As shown in FIGS. 5 and 6, below the fitting hole 9 that fits and supports the outlet pipe 20, a plurality of flow holes 11 are formed in the lower part of the partition plate 3. The residual water remaining in the shell 2 is freely circulated, and the silencer M is arranged in a forward tilting posture (see FIG. 1), so that the residual water in the shell 2 is circulated in them. The gas is collected forward through the hole 11, drawn into the outlet pipe 20 from the inlet of the outlet pipe 20, etc., and discharged to the outside together with the exhaust gas.

As shown in FIG. 6, if the maximum diameter of the expanded portion 20A at the front end of the outlet pipe 20 is φA, the maximum diameter of the expanded portion 20B at the rear end is φB, and the maximum diameter of the expanded portion 20C is φC, Dimensional relationship is
φC ≧ φA or φC ≧ φB, or φC ≧ φA and φC ≧ φB.

  As a result, the expansion portions 20A and 20B are expanded at the front end and the rear end of the outlet pipe 20, respectively, and then inserted into the fitting holes 9 of the partition plate 3, so that the expansion portion 20C of the outlet pipe 20 is inserted into the partition plate 3. The fitting hole 9 can be fitted and supported.

  The exhaust gas flowing into the second silencing chamber 5 flows into the outlet pipe 20 from the rear end (upstream end) of the outlet pipe 20 that has expanded. At this time, the rear end is widened, so that the exhaust gas easily flows into the outlet pipe 20. The exhaust gas flowing into the outlet pipe 20 flows to the tail pipe 30 and is discharged to the atmosphere. The outlet pipe 20 is formed with a drain hole / interference hole 21 which is a long hole communicating with the first silencing chamber 4, and the drain hole / interference hole 21 collects residual water accumulated in the shell 2. The resonance of the exhaust sound of the exhaust gas that is sucked into the outlet pipe 20 and flows through the outlet pipe 20 is prevented.

  The outlet pipe 20 is expanded in advance at the front and rear end portions in advance, and then inserted into the fitting hole 9 formed in the partition plate 3 so that the expansion portion 20C is fitted. If it fits into the hole 9 and the outer periphery of the expansion part 20C is welded to the fitting hole 9, the outlet pipe 20 can be fitted and supported on the partition plate 3 and fixed thereto.

Next, to explain how to assemble the silencer,
(1) As shown in FIG. 7A, the inlet pipe 10 and the outlet pipe 20 are respectively fitted into the fitting holes 9 of the partition plate 3 and are fixed by welding. And an intermediate assembly in which the three members of the partition plate 3 are integrated.

  (2) As shown in FIG. 7B, the partition plate 3 is press-fitted and fixed to the shell body 2a of the shell 2 as described above (at this time, the partition plate is not welded to the shell body 2a). Thereby, the intermediate assembly is fixed to the shell 2.

  (3) As shown in FIG. 7C, the front and rear end plates 2b and 2c are caulked and fixed to the front and rear ends of the shell body 2a, respectively.

  (4) As shown in FIG. 7D, the exhaust gas introduction pipe 1E is fitted to the front end (upstream end) of the inlet pipe 10 and the tail pipe 30 is fitted to the front end (downstream end) of the outlet pipe 20, respectively. The three of the gas introduction pipe 1E, the inlet pipe 10 and the front end plate 2b and the three of the tail pipe 30, the outlet pipe 20 and the front end plate 2b are welded simultaneously.

  Next, the operation of this embodiment will be described.

  Now, the engine E is operated, and the exhaust gas discharged therefrom is guided to the exhaust system Ex. The exhaust gas flowing through the exhaust system Ex enters the silencer M, where main exhaust noise is silenced.

  As shown by the arrow a in FIG. 4, most of the exhaust gas flowing into the inlet pipe 10 from the exhaust gas introduction pipe 1E enters the second silencing chamber 5 from the rear end opening as shown by the arrow b in FIG. As shown by an arrow c in the figure, a part thereof flows into the first silencing chamber 4 through the plurality of discharge holes 12, and from there through the many communication holes 6 formed in the partition plate 3, the second silencing chamber is provided. 5 flows into. In this process, the exhaust sound is attenuated by the expansion of the exhaust gas, and the exhaust sound is silenced.

  The exhaust gas that has flowed into the second silencing chamber 5 flows into the outlet pipe 20 from the rear end (upstream end) of the outlet pipe 20 that is expanded as shown by the arrow d in FIG. At this time, the expanded portion 20 </ b> B is formed and expanded at the rear end (upstream end) of the outlet pipe 20, so that the exhaust gas easily flows into the outlet pipe 20. The exhaust gas flowing into the outlet pipe 20 is discharged to the atmosphere through the tail pipe 30 as indicated by an arrow e in the figure. At this time, since the expansion part 20C becomes an expansion chamber, a slight reduction effect of exhaust noise can be obtained. Further, the drain hole / interference hole 21 formed by a long hole formed in the outlet pipe 20 sucks the residual water accumulated in the shell 2 into the outlet pipe 20 and resonates with the exhaust sound of the exhaust gas flowing in the outlet pipe 20. To prevent.

  Thus, according to this embodiment according to the present invention, between the expanded portions 20A and 20B at both ends of the outlet pipe 20, the expanded portion 20C having a diameter equal to or larger than at least one of the expanded portions 20A and 20B is provided. The outlet pipe 20 is inserted into the fitting hole 9 of the partition plate 3 from the side of the expansion portion having a diameter equal to or smaller than that of the expansion portion 20C, and the outlet pipe 20 is fitted to the partition plate 3 by the expansion portion 20C. Since the joint pipes are supported, it is not necessary to expand the outlet pipe 20 after the outlet pipe 20 is fitted and supported to the partition plate 3. Further, unlike the one proposed in Japanese Patent Application Laid-Open No. 200-9609, it is not necessary to separately form a flare pipe, so that the number of parts can be reduced and productivity can be improved. Further, the expansion portion 20 </ b> C formed in the outlet pipe 20 forms an expansion chamber, and can contribute to reduction of exhaust noise in the outlet pipe 20.

  Next, a second embodiment of the present invention will be described with reference to FIG.

  FIG. 8 is a sectional view of the fitting support portion of the outlet pipe of the silencer (corresponding to FIG. 6 of the first embodiment), and the same components as those in the first embodiment are denoted by the same reference numerals.

  In this second embodiment, the structure of the outlet pipe 20 is different from that of the first embodiment, and the outlet pipe 20 is a straight pipe 201 and a bent portion that is bent into a U-shape connected to the straight pipe 201. The pipe 202 is composed of an expanded portion 201A at one end (downstream end) of the straight pipe 201, and another widened portion at the end (upstream end) of the bent pipe 202. 202B is formed, and an expansion portion 203C is formed in the middle portion of the straight pipe 201. The maximum diameter φC of the expansion portion 203C is equal to or greater than the maximum diameter φA of the expanded portion 201A at one end of the straight pipe 201, that is, φC ≧ φA.

  The outlet pipe 20 is fitted and supported in the fitting hole 9 of the partition plate 3 from the straight pipe 201 side and welded thereto, and one end (downstream end) of the straight pipe 201 is the same as that of the first embodiment. Similarly, the tail pipe 30 and the front end plate 2b of the shell 2 are welded simultaneously. In addition, an expanded portion 202 </ b> B at one end of the bent pipe 202 is opened in the second silencing chamber 5.

  The exhaust gas flowing into the second silencing chamber 5 flows into the outlet pipe 20 from the rear end (upstream end) where the bent pipe 202 is expanded. At this time, the expanded portion 202 </ b> B is formed at the rear end (upstream end) of the outlet pipe 20, so that the exhaust gas easily flows into the outlet pipe 20. The exhaust gas flowing into the outlet pipe 20 is discharged to the atmosphere through the tail pipe 30.

  Therefore, the second embodiment also has the same effects as the first embodiment.

  As mentioned above, although the Example of this invention was described, this invention is not limited to the Example, A various Example is possible within the scope of the present invention. For example, in the first and second embodiments, the case where the present invention is applied to an outlet pipe supported by one partition plate has been described, but the present invention is applied to an exhaust pipe fitted and supported by a plurality of partition plates. Of course, it can be implemented.

Schematic side view of an exhaust system of an engine equipped with the silencer of the present invention 1 is a perspective view of the silencer as viewed in the direction of arrow 2 in FIG. Sectional view along line 3-3 in FIG. Sectional view along line 4-4 in FIG. Sectional view along line 5-5 in FIG. Sectional drawing which follows the 6-6 line of FIG. Diagram showing how to assemble silencer Sectional drawing of the fitting support part of the outlet pipe of the silencer concerning 2nd Example of this invention.

Explanation of symbols

2 ... Shell 3 ... Partition plate 4 ... Silence room (first silence room)
5 .... Silencer room (second silencer room)
20 ... Exhaust pipe (outlet pipe)
20A ..... expansion part 20B ..... expansion part 20C ..... expansion part 201 ..... straight pipe 201A ... ... Expanded part 202 ... Bend pipe 202B ... Expanded part 203C ... Expanded part

Claims (2)

Silencer that fits and supports a straight pipe exhaust pipe (20) having expanded portions (20A, 20B) at both ends to a partition plate (3) that partitions the inside of the shell (2) into a plurality of silencer chambers (4, 5). A vessel,
Between the expanded portions (20A, 20B) at both ends of the exhaust pipe (20), an expanded portion (20C) having a diameter equal to or larger than at least one of the expanded portions is formed, and the expanded portion (20C) A silencer characterized in that the pipe (20) is fitted and supported on the partition plate (3). A silencer for fitting and supporting an exhaust pipe (20) to a partition plate (3) that partitions the inside of the shell (2) into a plurality of silencer chambers (4, 5),
The exhaust pipe (20) includes a straight pipe (201) having an expanded portion (201A) at one end and a bent pipe (202) connected to the straight pipe (201), and is located between the straight pipe (201). An expansion part (203C) having a diameter equal to or larger than that of the expansion part (201A) is formed in the part, and the exhaust pipe (20) is fitted and supported on the partition plate (3) by the expansion part (203C). A silencer characterized by.

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