JP2013160084A - Muffling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain further reduction in size and improvement of muffling effects for an exhaust muffler in a communicating-pipe or through-hole structure.SOLUTION: In a muffling device 1, a body shell is comprised of an upstream-side shell member 2, a tubular member 3 joined to a downstream side of the upstream-side shell 2, and a downstream-side shell member 4 joined to a downstream side of the tubular member 3 and within the shell, a plurality of muffling chambers 7A, 7B, 7C for reducing noise with discharge of pulsation waves generated from a discharge port of an internal combustion engine are defined by a plurality of partition walls 6A, 6B, 6C from the upstream side to the downstream side. In the muffling device 1, communication members 8A, 8B guiding circulation of the pulsation waves are provided through the partition walls 6A, 6B, the inside of a communicating flow passage 9 for the pulsation waves is comprised of the communication members 8A, 8B per se and the outside thereof is comprised of the tubular member 3.

Description

  The present invention relates to a silencer in which a plurality of silencer chambers are continuously connected to reduce noise associated with emission of pulsating waves generated from an exhaust port of an internal combustion engine, and to an exhaust pipe of an internal combustion engine such as a motorcycle. Connected and used as an exhaust muffler.

The exhaust gas discharged from the internal combustion engine and ejected into the silencer through the introduction pipe is discharged into the outside air through the first silencer chamber, the second silencer chamber, and the third silencer chamber.
In the conventional silencer, a communication pipe that penetrates the partition wall or a through hole provided in the partition wall is used to sequentially flow the exhaust gas through the plurality of silencer chambers.

JP-A-9-21317

  In the conventional communication pipe or through-hole structure, there is a limit to increasing the offset amount to enhance the silencing effect, and further miniaturization and improvement of the silencing effect have been desired.

The present invention solves the above problems, and the invention according to claim 1
The main body outer shell includes an upstream outer shell member (2), a cylindrical member (3) whose upstream end is joined to the downstream end of the upstream outer shell member (2), and the cylindrical member (3). A downstream outer shell member (4) joined to the downstream end, and a plurality of silencer chambers (7A, 7A, 7A, 7B) for reducing noise associated with emission of pulsating waves generated from an exhaust port of the internal combustion engine in the outer shell. 7B, 7C) is a silencer (1) defined by a plurality of partition walls (6A, 6B, 6C) from the upstream side toward the downstream side.
A communicating member (8A, 8B) for guiding the flow of pulsating waves is provided through the partition wall (6A, 6B), and the communicating channel (9A) for the pulsating wave is disposed on the inner side of the communicating member (8A, 8B). ) Itself, and the outside is composed of the cylindrical member (3).

The invention according to claim 2 is the silencer (1) according to claim 1,
The silencer (1) has an inner end (5a) of an introduction pipe (5) through which the exhaust gas of the internal combustion engine is guided at an upstream end in the longitudinal direction of the cylindrical member (3), and the opening (5a) The partition wall (6A) has a facing structure.

The invention as set forth in claim 3 is the muffler (1) according to claim 2,
In the silencer (1), the partition wall (6B) including the communication member (8A, 8B) and the tail pipe (10) for discharging exhaust gas is connected to the communication member (8A, 8B) and the tail pipe ( The mounting position of 10) is provided in a distributed manner in the circumferential direction of the tubular member (3).

The invention as set forth in claim 4 is the silencer (1) according to claim 3,
The communicating member (8A, 8B) is characterized in that it has a halved shape obtained by dividing the tubular member in the axial direction.

A fifth aspect of the present invention provides the silencer (1) according to the third aspect,
The communication member (8A, 8B) is a member formed by bending a plate-like member into the half shape by pressing.

The invention according to claim 6 is the muffler device (1) according to any one of claims 1 to 5,
The silencer (1) is an exhaust muffler of an internal combustion engine for a vehicle. The cylindrical member (3) is provided with a drain discharge hole (12) at one end in the longitudinal direction, and is slightly inclined with respect to a horizontal plane. One communication member (8B) is arranged at the lowest position of the silencer cross section.

The invention according to claim 7 is the muffler device (1) according to any one of claims 1 to 6,
The communication member (8A) is formed integrally with the partition wall (6B).

The invention according to claim 8 is the muffler (1) according to claim 6 or 7,
When the vehicle is mounted, the communication members (8A, 8B) are provided on the lower left and right sides inside the main body, and the inlet (10a) of the tail pipe (10) is provided at the upper center in the left-right direction of the third silencing chamber (7C). The tail pipe (10) is installed so as to provide an outlet (10b) of the tail pipe (10) at the center of the dome-shaped downstream outer shell member (4).

In the invention of claim 1,
The outside of the communication channel (9) connecting the plurality of sound deadening chambers (7A, 7B, 7C) is composed of the tubular member (3) whose outer surface is exposed to the outside air. Since the cylindrical member (3) is used as a part of the constituent members of the communication channel (9), the communication members (8A, 8B) can be reduced in weight, thereby reducing the weight of the silencer (1). In addition, the cost can be reduced by reducing the amount of materials used. Further, since the exhaust gas passing through the communication channel (9) is cooled and contracted by the outside air via the cylindrical member (3), the gas pressure is lowered, and the noise reduction effect can be enhanced.

In the invention of claim 2,
An offset amount of the communication member (8A) with respect to the inner end (5a) of the introduction pipe (5) can be increased, and a communication member (8A) for the dynamic pressure of the pulsating wave emitted from the inner end (5a) of the introduction pipe (5) Intrusion into the communication channel (9) is suppressed, and the silencing effect can be enhanced.

In the invention of claim 3,
It is possible to increase the offset amount of the communication member (8A, 8B) and tail pipe (10) in the silencer chamber (7C), and the distance over which the exhaust gas crosses the silencer chamber (7C) becomes longer, so that the silencer effect is enhanced. Can do.

In the invention of claim 4,
The productivity of the communication members (8A, 8B) can be improved.

In the invention of claim 5,
The productivity of the communication members (8A, 8B) can be improved.

In the invention of claim 6,
The communicating member (8B) can also serve as a condensed water discharge passage between the muffler chambers in the exhaust muffler, simplifying the structure and reducing the cost. The condensed water that has flowed to the inner lower front end of the cylindrical member (3) is discharged from the drain discharge hole (12) at the lower front end of the cylindrical member (3).

In the invention of claim 7,
The structure can be simplified and the cost can be reduced.

In the invention of claim 8,
A sufficient distance between the communication member (8A, 8B) and the tail pipe (10) can be secured, and the bending of the tail pipe (10) can be made relatively small, so that the sound deadening performance can be increased. Since the outlet (10b) of the tail pipe (10) is at the center of the dome-shaped downstream outer shell member (4), the appearance is good.

It is a perspective view of the silencer concerning a 1st embodiment of the present invention. It is a longitudinal section of a silencer concerning a 1st embodiment of the present invention. It is a figure which shows the position of the communicating member and tail pipe which penetrate each partition. It is a perspective view which shows the shape of a communicating member. It is a figure which shows the position of the communicating member and tail pipe which penetrate each each partition of the silencer which concerns on 2nd Embodiment of this invention. It is a perspective view of the silencer concerning a 3rd embodiment of the present invention. It is a perspective view of the 2nd partition with a communication member of the said 3rd Embodiment. It is sectional drawing of the said 2nd partition with a said communication member. It is a top view of the sheet-metal raw material before performing the press work of the 2nd partition with a communication member.

  FIG. 1 is a view of a silencer 1 according to a first embodiment of the present invention, FIG. 1 is a perspective view, and FIG. 2 is a longitudinal sectional left view. The main body outer shell of the silencer 1 includes a conical upstream shell member 2, a cylindrical member 3, and a dome-shaped downstream shell member 4 connected to each other. In FIG. 1, the front side portions of the upstream outer shell member 2 and the cylindrical member 3 are removed and displayed. The introduction pipe 5 connected to the exhaust pipe of the internal combustion engine passes through the conical top portion of the upstream outer shell member 2 and is inserted into the main body, and the inner end 5a thereof opens into the main body. Each of the above parts consists of a single metal plate. The upstream outer shell member 2 and the cylindrical member 3 may have a double metal plate structure and a structure in which a sound absorbing material is sandwiched between the double metal plates.

  A first partition wall 6A, a second partition wall 6B, and a third partition wall 6C are fixed to the inside of the cylindrical member 3 in order from the front. A portion between the upstream outer shell member 2 and the first partition 6A is the first silencing chamber 7A, and a portion between the second partition 6B and the third partition 6C is the second silencing chamber 7B, and the first partition 6A and the second partition 6B. A portion sandwiched between the three is the third silencing chamber 7C. The number of the muffler chamber (first to third) follows the order of passage of the exhaust gas.

  Inside the silencer 1, a first communication member 8A penetrating both the first partition wall 6A and the second partition wall 6B is provided, and fixed to the partition walls 6A and 6B and the tubular member 3. A second communication member 8B penetrating the second partition wall 6B is provided, and is fixed to the second partition wall 6B and the cylindrical member 3. Each of these communicating members 8A and 8B has a shape in which the pipe is halved along the axis. The inner wall body of the communication flow path 9 formed by the communication members 8A and 8B of the noise reduction device 1 and connecting the plurality of noise reduction chambers is composed of the communication members 8A and 8B itself, and the outer wall body is formed of the outer surface. Is composed of the tubular member 3 exposed to the outside air. Since the tubular member 3 is used as a part of the constituent members of the communication flow path 9, the communication members 8A and 8B can be reduced in weight, thereby reducing the weight of the silencer. In addition, the cost can be reduced by reducing the amount of materials used. Furthermore, since the exhaust gas passing through the communication flow path 9 is cooled and contracted by the outside air via the cylindrical member 3, the gas pressure is reduced, and the noise reduction effect can be enhanced. A tail pipe 10 is provided through the second partition wall 6B, the third partition wall 6C, and the downstream outer shell member 4.

  This silencer 1 is an exhaust muffler of an internal combustion engine for a vehicle. The longitudinal direction of the cylindrical member 3 is arranged slightly inclined with respect to a horizontal plane, and the communication members 8A and 8B are arranged on the lower left and right sides inside the main body. Is provided. A drain notch 11 is provided at the lowermost part of the first partition 6A and the second partition 6B, and the condensed water flows to the inner lower front end of the cylindrical member 3, and a drain discharge hole provided at the lower front end of the cylindrical member 3. Discharged from 12.

  The first partition wall 6A faces the opening of the inner end 5a of the introduction pipe 5 connected to the exhaust pipe of the internal combustion engine and inserted through the top of the upstream outer shell member 2 into the main body. The first communication member 8A does not face. As a result, the offset amount of the first communication member 8A relative to the inner end 5a of the introduction pipe 5 can be increased, and the dynamic pressure of the pulsating wave generated from the inner end of the introduction pipe 5 can be reduced in the communication flow path 9 of the first communication member 8A. It is possible to suppress the intrusion into the inside and enhance the silencing effect.

  3A and 3B are views showing the positions of the communication members 8A and 8B and the tail pipe 10 penetrating each partition, FIG. 3A is a through position in the first partition 6A, and FIG. 3B is the second partition 6B. FIG. 3C shows a through position in the third partition 6C. In any of the drawings, the direction of the arrow up is directly above in the state of being attached to the vehicle. The first partition wall 6A and the second partition wall 6B are provided with a drain notch 11. In FIG. 3B, the two communicating members 8A and 8B and the tail pipe 10 are provided in a distributed manner in the circumferential direction of the cylindrical member 3, and maintain a sufficient distance from each other. Therefore, since the distance that the exhaust gas crosses the silencing chamber becomes long, the silencing effect can be enhanced.

  As shown in FIG. 3 (b), the communication members 8A and 8B are provided on the lower left and right sides inside the main body when mounted on the vehicle, and the inlet 10a of the tail pipe 10 is provided at the upper center in the left and right direction of the third silencing chamber 7C. As shown in FIG. 2, the tail pipe 10 is installed so that the outlet 10 b of the tail pipe 10 is provided at the center of the downstream outer shell member 4. A sufficient distance from the communication member can be ensured, and the bend of the tail pipe 10 can be made relatively small, so that the silencing performance can be increased. Since the outlet 10b of the tail pipe 10 is in the center of the dome-shaped downstream outer shell member 4 (FIGS. 1 and 2), the appearance is good.

  FIG. 4 is a perspective view showing the shape of the communication members 8A and 8B. FIG. 4 (a) is a communication member 8A and 8B in which the pipe is halved, and FIG. 4 (b) is a communication member 8A and 8B. The flanged communication members 8AF and 8BF are provided with a flange 13 at the edge of the shape of FIG. Any shape may be used. These are made by sheet metal pressing. Thereby, the productivity of the communication members 8A, 8B, 8AF, and 8BF can be improved. The communicating members 8A, 8B or 8AF, 8BF, the tail pipe 10 and the partition walls 6A, 6B are welded. Further, the communication members 8A, 8B or 8AF, 8BF and the tubular member 3 are also welded. The communicating members 8AF and 8BF with the flange 13 and the tubular member 3 can be spot-welded. The communicating members 8AF and 8BF provided with the flanges 13 at both edges have the effect of increasing the rigidity and improving the vibration proofing property.

  In the silencer 1 having the above-described structure shown in FIG. 1, exhaust gas discharged from an internal combustion engine (not shown) and injected into the silencer 1 through the introduction pipe 5 is a first silencer chamber 7A and a first communication member 8A. The second silencing chamber 7B, the second communication member 8B, the third silencing chamber 7C, and the tail pipe 10 are discharged into the outside air. The exhaust gas is muffled and silenced in the process of repeating expansion and contraction alternately through the large volume silencing chambers 7A, 7B, and 7C and the long communication members 8A and 8B. Discharged from the edge. Further, since the exhaust gas passing through the communication flow path 9 is cooled and contracted by the outside air through the cylindrical member 3, the gas pressure is lowered, and the noise reduction effect can be enhanced.

  This silencer has a so-called three-pass structure in which the gas flow passes through the second partition wall 6B three times through the first communication member 8A, the second communication member 8B, and the tail pipe 10. This is a structure in which the silencing effect is improved by lengthening the gas flow path.

  As an example of the manufacturing procedure of the silencer 1 described above, the first communication member 8A, the first partition wall 6A, the second partition wall 6B, the second communication member 8B, the tail pipe 10, and the third partition wall 6C are integrated in advance by welding. Is inserted into the tubular member 3 manufactured in advance, and the outer peripheral portion of each member in contact with the tubular member 3 is welded to the tubular member 3, and the remaining introduction pipe 5, the upstream outer shell member 2, and the downstream side The outer shell member 4 is assembled to the cylindrical member 3 and welded. The cylindrical member 3 can be finished in a cylindrical shape by winding a plate-shaped material around the integrated member and welding the mating surfaces.

  FIG. 5 is a diagram illustrating the arrangement of members of the silencer according to the second embodiment of the present invention, in which the positions of the communication members 8A and 8B and the tail pipe 10 that pass through the respective partitions of the silencer 1 are shown. Members having the same functions as those in the first embodiment are described using the same reference numerals. In any of the drawings, the direction of the arrow up is directly above in the state of being attached to the vehicle. The structure of the outer shell is the same as that of the silencer 1 described above, and the only difference is that the positions of the communication members 8A and 8B and the tail pipe 10 are different. This is because the second communication member 8B also serves as a condensed water discharge passage between the second silencing chamber 7B and the third silencing chamber 7C, thereby reducing the cost of draining the second partition wall 6B. Is intended to save.

  For this purpose, the positions of the communication members 8A and 8B and the tail pipe 10 are rotated by about 60 degrees as compared with the first embodiment. That is, one of the two communication members 8A and 8B attached to the second partition wall, the second communication member 8B is arranged at the lowest position in the cross section of the silencer. A drain discharge hole 12 is provided at the inner lower front end of the cylindrical member 3. 5A shows the through position of the first partition 6A, FIG. 5B shows the through position of the second partition 6B, and FIG. 5C shows the through position of the third partition 6C. The first partition wall 6A is provided with a water drain notch, but the second partition wall 6B is not provided with a water drain notch because the communication member 6B has a water drain function. With the above configuration, the second communication member 8B can also serve as a condensed water discharge passage between the second silencing chamber 7B and the third silencing chamber 7C in the exhaust muffler, the structure can be simplified, and the second partition wall 6B can be simplified. It is possible to save the cost of draining and notching. The condensed water flowing to the inner lower front end of the cylindrical member 3 is discharged from the drain discharge hole 12 at the lower front end of the cylindrical member 3.

  FIG. 6 is a perspective view of the silencer 15 according to the third embodiment of the present invention. Members having the same functions as those in the first embodiment are described using the same reference numerals. In the figure, the front side portions of the upstream outer shell member 2 and the cylindrical member 3 are removed and shown. The feature of this embodiment is that the first communication member 8A is integrally formed with the second partition wall 6B in the first embodiment, that is, the “second partition wall with communication member” 16 is provided. The second partition wall 16 with the communication member includes a partition wall portion 16a and a communication member portion 16b. The communicating member portion 16b extends forward and passes through the first partition wall 6A and opens into the first silencing chamber 7A. That is, the communication member portion 16b functions in the same manner as the first communication member 8A of the first embodiment. The structure can be simplified by this integrally formed member, and the cost for welding and the like can be suppressed. Instead of the half-shaped second communication member 8B provided in the first embodiment, an intermediate pipe 17 that performs the same function is provided. The tail pipe 10 is the same in shape and action as that of the first embodiment.

  In the silencer 15, exhaust gas discharged from an internal combustion engine (not shown) and injected into the silencer 15 through the introduction pipe 5 is in the first silencer chamber 7A, the communication member portion 16b, the second silencer chamber 7B, and the middle. It is discharged into the outside air through the pipe 17, the third silencing chamber 7C, and the tail pipe 10.

  FIG. 7 is a perspective view of the second partition wall 16 with the communication member of the third embodiment. FIG. 8 is a sectional view of the second partition wall 16 with the communication member. The communication member portion 16b of the second partition wall 16 is made sufficiently long because it needs to send exhaust gas over three chambers. The second partition wall 16 with the communication member is manufactured by aluminum die casting or sheet metal pressing. In FIG. 7, an insertion hole 18 of the intermediate pipe 17, an insertion hole 19 of the tail pipe 10, and a drain hole 21 are provided in the partition wall portion 16 a of the second partition wall 16 with the communication member.

  FIG. 9 is a plan view of the sheet metal material 20 before the press work when the second partition wall 16 with the communication member is manufactured by press work. A broken line is a fold line of the second partition wall. An insertion hole 18 for the intermediate pipe 17 and an insertion hole 19 for the tail pipe 10 are provided. A hole for forming the drain hole 21 is provided in a portion to be the drain hole 21. By pressing this material, the second partition wall 16 with the communication member can be made.

  DESCRIPTION OF SYMBOLS 1 ... Silencer, 2 ... Upstream outer shell member, 3 ... Cylindrical member, 4 ... Downstream outer shell member, 5 ... Introducing pipe, 5a ... Inner end of introducing pipe, 6A ... First partition, 6B ... Second Partition wall, 6C ... third partition wall, 7A ... first silencer chamber, 7B ... second silencer chamber, 7C ... third silencer chamber, 8A ... first communication member, 8B ... second communication member, 9 ... communication flow path, 10 ... Tail pipe, 10a ... Tail pipe inlet, 10b ... Tail pipe outlet

Claims (8)

The main body outer shell includes an upstream outer shell member (2), a cylindrical member (3) whose upstream end is joined to the downstream end of the upstream outer shell member (2), and the cylindrical member (3). A downstream outer shell member (4) joined to the downstream end, and a plurality of silencer chambers (7A, 7A, 7A, 7B) for reducing noise associated with emission of pulsating waves generated from an exhaust port of the internal combustion engine in the outer shell. 7B, 7C) is a silencer (1) defined by a plurality of partition walls (6A, 6B, 6C) from the upstream side toward the downstream side.
A communicating member (8A, 8B) for guiding the flow of pulsating waves is provided through the partition wall (6A, 6B), and the communicating channel (9A) for the pulsating wave is disposed on the inner side of the communicating member (8A, 8B). ) The silencer (1), characterized in that the outside is composed of the tubular member (3).   The silencer (1) has an inner end (5a) of an introduction pipe (5) through which the exhaust gas of the internal combustion engine is guided at an upstream end in the longitudinal direction of the cylindrical member (3), and the opening (5a) The silencer (1) according to claim 1, characterized in that the partition wall (6A) has a facing structure.   In the silencer (1), the partition wall (6B) including the communication member (8A, 8B) and the tail pipe (10) for discharging exhaust gas is connected to the communication member (8A, 8B) and the tail pipe ( The silencer (1) according to claim 2, wherein the mounting positions of (10) are distributed in the circumferential direction of the tubular member (3).   The silencer (1) according to claim 3, wherein the communicating member (8A, 8B) has a half-divided shape obtained by dividing a tubular member in the axial direction.   The silencer (1) according to claim 3, wherein the communication member (8A, 8B) is a member formed by bending a plate-like member into the half shape by pressing.   The silencer (1) is an exhaust muffler of an internal combustion engine for a vehicle. The cylindrical member (3) is provided with a drain discharge hole (12) at one end in the longitudinal direction, and is slightly inclined with respect to a horizontal plane. The muffler (1) according to any one of claims 1 to 5, wherein one communication member (8B) is arranged at the lowest position in the cross section of the muffler.   The silencer (1) according to any one of claims 1 to 6, wherein the communication member (8A) is integrally formed with the partition wall (6B).   When the vehicle is mounted, the communication members (8A, 8B) are provided on the lower left and right sides inside the main body, and the inlet (10a) of the tail pipe (10) is provided at the upper center in the left-right direction of the third silencing chamber (7C). The tail pipe (10) is provided so as to provide an outlet (10b) of the tail pipe (10) in the center of the dome-shaped downstream outer shell member (4). The silencer (1) according to claim 7.

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