JP6742790B2 - Exhaust silencer - Google Patents

Description

The present invention relates to an exhaust silencer suitable as an automobile exhaust silencer, and more particularly to an exhaust silencer including a container having a volume chamber connected to a branch portion in the middle of an exhaust pipe and communicating with an exhaust passage. Regarding

As a conventional exhaust silencer, as described in Patent Document 1, an exhaust pipe having an exhaust passage for discharging exhaust gas of an internal combustion engine, and a volume chamber connected to a branch portion in the middle of the exhaust pipe and communicating with the exhaust passage. There is also a container provided with, and uses this container as a resonance type silencer.

The exhaust silencer disclosed in Patent Document 1 causes a resonance phenomenon to occur in a sound wave having a specific frequency in exhaust sound depending on the volume of the volume chamber in the container and the area of the communication passage that connects the volume chamber of the container and the exhaust passage. And perform the muffling function of attenuating the sound.

JP 2007-192131 JP

In the vehicle equipped with the exhaust silencer described in Patent Document 1, the container connected to the branch portion in the middle of the exhaust pipe functions as a resonance silencer, and quiet running in an urban area can be realized.

However, in the vehicle equipped with the exhaust silencer described in Patent Document 1, the volume of exhaust cannot be increased due to the presence of the resonance silencer, exhaust back pressure becomes high, exhaust leakage is poor, and the output of the internal combustion engine decreases. It is not suitable for circuit driving etc.

An object of the present invention is to make it possible, in an exhaust silencer, to easily switch between an urban running mode in which exhaust volume is low and a circuit running mode in which exhaust volume is high and output can be increased.

The invention according to claim 1 is an exhaust pipe provided under a floor of a vehicle and provided with an exhaust passage for discharging exhaust gas of an internal combustion engine, and a volume chamber connected to a branch portion in the middle of the exhaust pipe and communicating with the exhaust passage. and a container provided with a container, with an opening capable of opening and closing the volume chamber to the outside space, vehicle exhaust silencer device including a switching means for switching the opening in the open and closed states The exhaust outlet of the tail pipe attached to the opening of the container passes through a lower portion or a concave portion of the rear bumper at a position in front of the rear bumper protruding below the floor bottom surface of the vehicle. Instead, it is opened vertically downward .

According to a second aspect of the present invention, in addition to the first aspect, the opening/closing means is attached to the opening, and a lid for closing the volume chamber with respect to the external space is attached to the opening. A tail pipe that opens the volume chamber to the external space is provided, and the lid and the tail pipe can be alternately attached to and detached from the opening.

According to a third aspect of the present invention, in addition to the first aspect of the invention, the opening/closing means is an opening/closing valve arranged in a tail pipe attached to the opening to open the volume chamber to an external space. It was done like this.

According to a fourth aspect of the present invention, in addition to the third aspect of the invention, the opening/closing valve is controlled to be opened/closed in accordance with the operating state of the internal combustion engine.

The invention according to claim 5 is the exhaust silencer for an automobile according to any one of claims 1 to 4 , wherein the exhaust silencer is installed under a floor of a vehicle, and the container is a rear of the vehicle. It is installed so as to be adjacent to the side of the exhaust pipe in the horizontal direction in front of the bumper .

(Claim 1)
(a) The container is provided with an opening for opening and closing the volume chamber with respect to the external space, and an opening/closing means for switching the opening between an open state and a closed state.

When the opening/closing means closes the opening, the exhaust gas entering the volume chamber of the container becomes a dead end. Therefore, since the container constitutes a resonance type silencer, it constitutes an urban traveling mode in which the exhaust sound volume is reduced.

When the opening/closing means opens the opening, the exhaust gas entering the volume chamber of the container is discharged to the external space through the opening. Therefore, the container does not constitute a resonance silencer but constitutes a circuit running mode in which exhaust volume is high and output can be increased.
When the exhaust silencer is installed under the floor of the vehicle, the exhaust outlet of the tail pipe attached to the opening of the container opens vertically downward at a position forward of the vehicle rear bumper. Therefore, the exhaust gas discharged from the opening through the tail pipe is discharged vertically downward without hitting the rear bumper. It is possible to prevent the exhaust gas discharged through the tail pipe from being blown onto the lower surface of the vehicle floor material, the resin bumper, etc., and protect the vehicle floor material and the resin bumper from thermal damage due to contact with the exhaust gas.
Further, since the tail pipe attached to the opening of the container does not pass below the lower part of the rear bumper protruding below the floor bottom surface of the vehicle, the minimum ground clearance of the vehicle is not lowered, There is no need to additionally machine a recess for extending the tail pipe in the rear bumper.

(Claim 2)
(b) By alternately attaching and detaching the lid and the tail pipe to the opening of the container, without changing the main part of the exhaust silencer (combination of the exhaust pipe and the container), the urban driving mode of the above (a) And circuit driving mode can be easily switched.

(Claim 3)
(c) By arranging an opening/closing valve in the tail pipe attached to the opening of the container, the main part of the exhaust silencer (combination of exhaust pipe and container) is not changed, and You can easily switch between city driving mode and circuit driving mode.

(Claim 4)
(d) The open/close valve is controlled to be opened/closed according to the operating conditions such as the engine speed of the internal combustion engine, the engine cooling water temperature, and the exhaust temperature. And can be selectively adopted so as to be optimal according to the operating state.

(Claim 5 )
(e) When the exhaust silencer is installed under the floor of the vehicle, the container is arranged so as to crawl on the underside of the floor that is in front of the rear bumper of the vehicle and vertically above the lower edge of the rear bumper. Further, it is arranged so as not to be vertically above or below the exhaust pipe but to be adjacent to a horizontal side of the exhaust pipe. Therefore, the installation of the container under the floor of the vehicle does not lead to an excessively low minimum ground clearance with respect to the ground surface of the vehicle, and does not become an obstacle to the vehicle securing a certain minimum ground clearance.

FIG. 1 is a schematic plan view showing an example of an automobile exhaust device. FIG. 2 is a schematic plan view showing another example of an automobile exhaust system. FIG. 3 shows an exhaust silencer, (A) is a schematic plan view showing an urban driving mode, and (B) is a schematic plan view showing a circuit driving mode. FIG. 4 is a schematic diagram showing the exhaust silencer disassembled. FIG. 5 is a schematic plan view showing a modified example of the exhaust silencer. FIG. 6 is a schematic view of the exhaust noise suppressor installed under the floor of the vehicle as viewed from the ground surface side. FIG. 7 is a schematic view of an exhaust silencer installed under the floor of a vehicle as viewed from the rear of the vehicle. FIG. 8 is a front view showing the exhaust silencer. FIG. 9 is a rear view showing the exhaust silencer. FIG. 10 is a plan view showing the exhaust silencer. FIG. 11 is a bottom view showing the exhaust silencer. FIG. 12 is a right side view showing the exhaust silencer. FIG. 13 is a left side view showing the exhaust silencer.

1 and 2 show an exhaust system 100 for an automobile, which exhausts exhaust gas from a V-type engine (internal combustion engine) 1. In FIG. 1 and FIG. 2, 2 is each left and right exhaust manifold connected to each left and right bank of the engine 1, 3 is each left and right catalytic converter connected to each exhaust manifold 2, 4 is connected to each catalytic converter Left and right front pipes 5 and 5 are left and right center pipes connected to the front pipes 4, and 10 are left and right exhaust silencers connected to the center pipes 5. In the exhaust device 100, the left and right constituent members 2 to 5, 10 are symmetrically arranged with respect to the center line of the vehicle.

In the exhaust device 100 shown in FIG. 1, the left and right front pipes 4 are gathered together by the gathering unit 4A, and the left and right center pipes 5 are gathered together by the gathering unit 5A, so that the both front pipes 4 and the both center pipes 5 are gathered together. The parts 4A and 5A are connected together. On the other hand, in the exhaust device 100 shown in FIG. 2, the left and right front pipes 4 are not assembled, and the left and right center pipes 5 are not assembled, the left front pipe 4 and the left center pipe 5 are connected, and the right front pipe 4 and the right front pipe 4 are connected. The center pipe 5 is connected.

The exhaust system 100 silences the exhaust sound of the engine 1 by a center muffler 6 included in the center pipe 5, a main muffler 12 included in the exhaust silencer 10, a resonance silencer 20A configured by a container 20 included in the exhaust silencer 10, and the like. It is possible.

As shown in FIGS. 3, 4, and 8 to 13, the exhaust silencer 10 has an exhaust pipe 11 which is connected to the center pipe 5 by a joint 11F and has an exhaust passage 11A for exhausting exhaust gas of the engine 1. A cylindrical main muffler 12 is provided around the middle portion of the exhaust pipe 11, and a main tail pipe 13 for exhausting exhaust gas to the external space is provided at the end of the exhaust pipe 11. The main muffler 12 can be configured by a sound absorbing silencer in which an expansion chamber 12A is formed around an intermediate portion of the exhaust pipe 11, and the expansion chamber 12A is filled with a sound absorbing material 12B. However, the main muffler 12 may be configured by a composite muffler that combines a plurality of muffling methods such as an expansion type, a resonance type, and an interference type.

The exhaust silencer 10 has a container 20 that is connected to a branch portion 14 located on the upstream side of the main muffler 12 of the exhaust pipe 11 and has a volume chamber 21 that is connected to the exhaust passage 11A via a communication passage 22. ..

The container 20 is provided with a volume chamber 21 having a constant volume in the shape of a tank, one end side of the volume chamber 21 is connected to the exhaust passage 11A of the exhaust pipe 11 by a communication passage 22, and the other end side of the volume chamber 21 is an external space. An opening 23 that can be opened and closed is provided, and an opening/closing means 30 that switches the opening 23 between an open state and a closed state is provided.

When the opening/closing means 30 closes the opening 23, the exhaust gas entering the volume chamber 21 of the container 20 becomes a dead end as shown in FIG. Therefore, the container 20 constitutes the resonance silencer 20A. In the resonance silencer 20A, when the volume of the volume chamber 21 is increased, the length of the communication passage 22 is increased, and the passage area of the communication passage 22 is decreased, the resonance frequency can be decreased, and conversely, the volume can be reduced. When the volume of the chamber 21 is reduced, the length of the communication passage 22 is reduced, and the passage area of the communication passage 22 is increased, the resonance frequency can be increased. With this resonance silencer 20A, for example, a low-frequency sound can be silenced, and an urban traveling mode in which exhaust sound volume is reduced can be configured.

When the opening/closing means 30 opens the opening 23, the exhaust gas entering the volume chamber 21 of the container 20 is discharged to the external space through the opening 23, as shown in FIG. 3B. Therefore, the container 20 does not constitute the resonance silencer 20A, but constitutes a circuit traveling mode in which exhaust volume is high and output can be increased.

As shown in FIG. 4, the opening/closing means 30 includes a lid 31 attached to the opening 23 to close the volume chamber 21 with respect to the external space, and a lid 31 attached to the opening 23 to attach the volume chamber 21 to the external space. The tail pipe 32 is opened by opening the lid 31 and the tail pipe 32 can be alternately attached to and detached from the opening 23. The tail pipe 32 is provided with an exhaust outlet 32A (FIG. 4) that opens downward (however, the exhaust outlet 32A of the tail pipe 32 does not necessarily have to be opened downward, but may be opened rearward in the horizontal direction). Is also good). The lid 31 and the tail pipe 32 are provided with annular flange portions 31F, 32F at their connecting ends, and these flange portions 31F, 32F are butted against an annular flange portion 23F provided in the opening 23 of the container 20 to form a G coupling. The lid 31 or the tail pipe 32 can be attached to the opening 23 of the container 20 by fastening the flanges 31F and 32F and the flange 23F of the opening 23 with a fastener 33 such as. In the exhaust silencer 10 shown in FIGS. 8, 10, 11, and 13, a tail pipe 32 shown by a broken line is attached to the opening 23 of the container 20. However, in the exhaust silencer 10, the lid 31 that replaces the tail pipe 32 may be attached to the opening 23 of the container 20.

That is, by alternately attaching and detaching the lid 31 and the tail pipe 32 to and from the opening 23 of the container 20, the main part of the exhaust silencer 10 (the combination of the exhaust pipe 11 and the container 20) is not changed and the above-mentioned operation is performed. It is possible to easily switch between the city driving mode (FIG. 3A) and the circuit driving mode (FIG. 3B).

The exhaust silencer 10 shown in FIG. 5 has an opening/closing means 40 instead of the opening/closing means 30. The opening/closing means 40 is attached to the opening 23 of the container 20 and is arranged on a tail pipe 41 (which may be the same as the tail pipe 32 of the opening/closing means 30) which opens the volume chamber 21 to the external space. It is constituted by the opened/closed valve 42. The drive unit 42M of the opening/closing valve 42 is driven according to the operating state of the engine 1 (engine speed, engine cooling water temperature, exhaust temperature, etc.) transmitted from the electronic control unit (ECU) 50 of the engine 1, and the opening/closing valve 42M is operated. The opening degree of 42 is controlled to the optimum opening degree for the operating state.

That is, by arranging the opening/closing valve 42 on the tail pipe 41 attached to the opening 23 of the container 20, without changing the main part of the exhaust silencer 10 (the combination of the exhaust pipe 11 and the container 20). , It is possible to easily switch between the city driving mode and the circuit driving mode described above.

Then, the opening/closing valve 42 is controlled to be opened/closed in accordance with the engine speed of the engine 1, the engine cooling water temperature, the exhaust temperature, and the like, so that the above-described urban traveling mode and circuit traveling mode are concerned. It can be selectively adopted so as to be optimum according to the driving condition. Therefore, by setting the opening/closing valve 42 to an arbitrary intermediate opening between fully closed and fully opened, it is possible to obtain an appropriate exhaust sound volume and an appropriate output according to the operating state of the engine 1.

The exhaust silencer 10 includes a container 20, a communication passage 22, and an opening 23 (lid 31, tail pipes 32, 41) in a plan view (FIGS. 3 and 12) installed under the floor of the automobile 200. The exhaust pipe 11 and the main muffler 12 are arranged adjacent to the side. When the exhaust silencer 10 is installed under the floor of the automobile 200 in a side view (FIGS. 10 and 11), the container 20, the communication passage 22, and the opening 23 (the lid 31, the tail pipes 32, 41) are the exhaust pipes. 11 and the main muffler 12 are arranged at the same height level.

6 and 7 show a state in which the exhaust device 100 and the exhaust silencer 10 thereof are installed under the floor of the automobile 200. The exhaust silencer 10 is attached to the lower surface of the floor material 201 of the automobile 200 by a mounting bracket, and has an exhaust pipe 11, a main muffler 12, a container 20 (volume chamber 21), a communication passage 22, an opening 23, a lid 31, or a tail pipe. 32 is extended so as to crawl close to the lower surface of the floor material 201, and the main tail pipe 13 is housed in a recess 202A formed by recessing the lower edge of the rear bumper 202 of the automobile 200.

At this time, the exhaust outlet 32A of the tail pipe 32 attached to the opening 23 of the container 20 is located in front of the rear bumper 202 of the automobile 200 (the front means the forward direction of the automobile 200) and faces downward in the vertical direction. Opened (facing the ground surface). The exhaust outlet 13A of the main tail pipe 13 housed in the recess 202A of the rear bumper 202 is opened rearward in the horizontal direction at the rear surface position of the rear bumper 202.

Therefore, the exhaust gas discharged from the opening 23 of the container 20 via the tail pipe 32 is discharged vertically downward without hitting the rear bumper 202. The exhaust gas exhausted through the tail pipe 32 is prevented from being blown onto the floor material 201 of the automobile 200, the resin bumper 202, etc., and the heat generated by the contact between the floor material 201 of the automobile 200 and the resin bumper 202 with the exhaust gas. Protects against physical damage.

Further, since the tail pipe 32 attached to the opening 23 of the container 20 does not pass under the rear bumper 202 protruding below the floor bottom surface of the vehicle 200, the minimum ground clearance of the vehicle 200 is reduced. There is no need to reduce the height, and it is not necessary to additionally process the extension recess of the tail pipe 32 in the rear bumper 202.

Further, the container 20 is installed along the lower surface of the floor material 201 located on the front side of the rear bumper 202 of the automobile 200 so as to be adjacent to the exhaust pipe 11 and the main muffler 12 in the horizontal direction.

That is, when the exhaust silencer 10 is installed under the floor of the automobile 200, the container 20 is placed in front of the rear bumper 202 of the automobile 200 on the floor lower surface that is vertically higher than the lower edge of the rear bumper 202. It is arranged so as to crawl, and further, it is arranged so as not to be vertically above or below the exhaust pipe 11 but to be adjacent to a lateral side of the exhaust pipe 11 in the horizontal direction. Therefore, the installation of the container 20 under the floor of the automobile 200 does not lead to an excessively low minimum ground clearance of the automobile 200 with respect to the ground surface, but is an impeding factor for the vehicle 200 to secure a certain minimum ground clearance. do not become.

Although the embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration of the present invention is not limited to this embodiment, and even if there is a design change or the like without departing from the scope of the present invention. Included in the present invention.

According to the present invention, in the exhaust silencer, it is possible to easily switch between the city running mode in which the exhaust sound volume is low and the circuit running mode in which the exhaust sound volume is high and the output can be increased.

1 engine (internal combustion engine)
10 Exhaust Muffler 11 Exhaust Pipe 11A Exhaust Passage 14 Branch 20 Container 21 Volume Chamber 22 Communication Passage 23 Opening 30 Opening/Closing Means 31 Lid 32 Tail Pipe 32A Exhaust Outlet 40 Opening/Closing Means 41 Tail Pipe 42 Opening/Closing Valve 200 Automobile (vehicle)
201 Floor material 202 Rear bumper

Claims (5)

Installed under the floor of the vehicle,
An exhaust pipe having an exhaust passage for discharging exhaust gas of the internal combustion engine, and a container provided with a volume chamber connected to a branch portion in the middle of the exhaust pipe and communicating with the exhaust passage ,
A container is provided with an opening that can open and close the volume chamber with respect to the external space, and an exhaust muffler for automobiles that is provided with opening and closing means that switches the opening between an open state and a closed state ,
The exhaust outlet of the tail pipe attached to the opening of the container is positioned in front of the rear bumper projecting below the floor bottom surface of the vehicle, and is located in the vertical direction without passing through the lower portion or recess of the rear bumper. An exhaust muffler for automobiles that opens downward . The opening/closing means includes a lid attached to the opening to close the volume chamber to the external space, and a tail pipe attached to the opening to open the volume chamber to the external space. The exhaust silencer for an automobile according to claim 1, wherein the lid and the tail pipe can be alternately attached to and detached from the opening. The exhaust muffler for a vehicle according to claim 1, wherein the opening/closing means comprises an opening/closing valve attached to the opening and arranged in a tail pipe that opens the volume chamber to an external space. The exhaust silencer for a vehicle according to claim 3, wherein the opening/closing valve is controlled to be opened/closed according to an operating state of the internal combustion engine. The exhaust silencer is a vehicle exhaust silencer installed under the floor of a vehicle,
It said container, vehicle exhaust muffler according to any one of claims 1 to 4 is installed so as to be adjacent in the horizontal direction of the side near for the exhaust pipe in the front side of the rear bumper of the vehicle.

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