JP2008240587A

JP2008240587A - Vehicular muffler

Info

Publication number: JP2008240587A
Application number: JP2007080497A
Authority: JP
Inventors: Kenji Sugano; 健司菅野
Original assignee: Calsonic Kansei Corp
Current assignee: Marelli Corp
Priority date: 2007-03-27
Filing date: 2007-03-27
Publication date: 2008-10-09

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular muffler capable of preventing generation of an abnormal sound caused by a louver, even when a flow speed of exhaust gas is increased by reducing a diameter of an inner pipe. <P>SOLUTION: This vehicular muffler 1 is composed of the straight pipe-shaped inner pipe 2 for flowing the exhaust gas and a substantially cylindrical outer pipe 4 having a resonance chamber 3 between the outer pipe and this inner pipe 2 and arranged outside the inner pipe 2, and is formed by arranging the louver 8 having a pair of small holes 11a and 11b in the inner pipe 2. The louver 8 is arranged toward the inside of the inner pipe 2. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

本発明は、車両用消音器に関し、特に、共鳴型の消音室を有する車両用消音器の改良技術に関する。 The present invention relates to a vehicle silencer, and more particularly to an improved technique for a vehicle silencer having a resonance-type silencer.

従来、排気ガスが流通する内管と、この内管との間に共鳴室を有して該内管の外側に設けられる外管とから構成され、内管の外周に小孔を有するルーバが設けられた車両用消音器車両用消音器の技術が公知になっている（特許文献１参照）。
特開２００４−３６５８９号公報 Conventionally, a louver having an inner pipe through which exhaust gas flows and an outer pipe provided outside the inner pipe with a resonance chamber between the inner pipe and having a small hole on the outer circumference of the inner pipe is provided. The vehicle silencer provided is well known in the art (see Patent Document 1).
JP 2004-36589 A

しかしながら、従来の発明にあっては、排気ガスの流速（流量）や小孔の径によって生じる異音（笛吹音）を防止することを目的としてルーバを設けているが、内管の径をさらに小さくして排気ガスの流速を大きくすると、ルーバを起因とする異音が発生してしまうという問題点があった。 However, in the conventional invention, a louver is provided for the purpose of preventing abnormal noise (flute blowing sound) caused by the exhaust gas flow velocity (flow rate) and the diameter of the small hole. If the exhaust gas flow rate is increased by reducing the exhaust gas flow rate, there is a problem that abnormal noise caused by the louver occurs.

本発明は上記課題を解決するためになされたものであって、その目的とするところは、内管の径を小さくして排気ガスの流速を大きくした場合でもルーバに起因する異音の発生を防止できる車両用消音器を提供することである。 The present invention has been made to solve the above-mentioned problems, and the object of the present invention is to generate noise caused by the louver even when the diameter of the inner tube is reduced and the flow rate of the exhaust gas is increased. It is providing the silencer for vehicles which can be prevented.

本発明の請求項１記載の発明では、排気ガスが流通する内管と、この内管との間に共鳴室を有して該内管の外側に設けられる外管とから構成され、前記内管に一対の小孔を有するルーバが設けられた車両用消音器において、前記ルーバを内管の内側へ向けて設けたことを特徴とする。 The invention according to claim 1 of the present invention comprises an inner pipe through which exhaust gas flows, and an outer pipe provided outside the inner pipe with a resonance chamber between the inner pipe and the inner pipe. In a vehicle silencer in which a louver having a pair of small holes is provided in a pipe, the louver is provided toward an inner side of the inner pipe.

本発明の請求項１記載の発明にあっては、排気ガスが流通する直管状の内管と、この内管との間に共鳴室を有して該内管の外側に設けられる略円筒状の外管とから構成され、前記内管に一対の小孔を有するルーバが設けられた車両用消音器において、前記ルーバを内管の内側へ向けて設けたため、内管の径を小さくして排気ガスの流速を大きくした場合でもルーバに起因する異音の発生を防止できる。 In the invention according to claim 1 of the present invention, a substantially cylindrical shape which is provided outside the inner tube with a straight inner tube through which exhaust gas flows and a resonance chamber between the inner tube and the inner tube. In the vehicle silencer in which the inner pipe is provided with a louver having a pair of small holes, the louver is provided toward the inner side of the inner pipe. Even when the flow rate of the exhaust gas is increased, it is possible to prevent abnormal noise caused by the louver.

以下、この発明の実施例を図面に基づいて説明する。 Embodiments of the present invention will be described below with reference to the drawings.

以下、実施例１を説明する。
図１は本発明の実施例１の車両用消音器の内部を説明する図、図２は図１のＳ２−Ｓ２線における断面図、図３は本実施例１のルーバの拡大図、図４は図３のＳ４−Ｓ４線における断面図、図５は図３のＳ５−Ｓ５線における断面図である。 Example 1 will be described below.
1 is a diagram for explaining the interior of a vehicle silencer according to a first embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line S2-S2 of FIG. 1, FIG. 3 is an enlarged view of a louver according to the first embodiment, and FIG. Is a sectional view taken along line S4-S4 in FIG. 3, and FIG. 5 is a sectional view taken along line S5-S5 in FIG.

先ず、全体構成を説明する。
図１に示すように、本実施例１の車両用消音器１では、排気ガスが流通する直管状の内管２と、この内管２との間に共鳴室３を有して該内管２の外側に設けられる略円筒状の外管４とから構成され、全て金属製となっている。 First, the overall configuration will be described.
As shown in FIG. 1, the vehicle silencer 1 of the first embodiment has a straight tubular inner tube 2 through which exhaust gas flows and a resonance chamber 3 between the inner tube 2 and the inner tube 2. 2 and a substantially cylindrical outer tube 4 provided on the outer side of 2, all made of metal.

内管２の排気ガス上流側端部５は拡径されると共に、その外周に外管４の縮径した縮径部４ａが図示を省略するスポット溶接等で複数箇所に亘って固定されている。
一方、内管２の排気ガス下流側端部６の外周には、環状の金属製メッシュ部材７が外嵌した状態で図示を省略するスポット溶接等で複数箇所に亘って固定されると共に、この金属製メッシュ部材７は外管４の縮径部４ｂの内側に当接して摺動可能に固定支持され、これによって、内管２の排気ガスによる軸方向への熱膨張を許容できるようになっている。 The exhaust gas upstream end portion 5 of the inner tube 2 is expanded in diameter, and the reduced diameter portion 4a of the outer tube 4 is fixed to a plurality of locations on the outer periphery thereof by spot welding or the like (not shown). .
On the other hand, the exhaust pipe downstream end portion 6 of the inner pipe 2 is fixed to a plurality of locations by spot welding or the like (not shown) in a state where the annular metal mesh member 7 is externally fitted. The metal mesh member 7 abuts on the inner side of the reduced diameter portion 4b of the outer tube 4 and is slidably fixed and supported, so that thermal expansion in the axial direction by the exhaust gas of the inner tube 2 can be allowed. ing.

そして、内管２の外周には、後述するルーバ８が千鳥状に複数形成されている。
具体的には、図２〜５に示すように、本実施例１のルーバ８は、内管２の軸方向両側に側壁9,10を有した状態で該内管２を内側へ向けて略Ｖ字形に切り起こして形成され、これにより、内管２の周方向に開口した一対の小孔11a,11bが備えられている。
なお、ルーバ８の幅、高さ、Ｖ字形の角度等の寸法、及び配置等については適宜設定できる。 A plurality of louvers 8 described later are formed in a staggered pattern on the outer periphery of the inner tube 2.
Specifically, as shown in FIGS. 2 to 5, the louver 8 according to the first embodiment substantially has the inner tube 2 facing inward with the side walls 9 and 10 on both axial sides of the inner tube 2. A pair of small holes 11a and 11b which are formed by cutting and raising into a V shape and opened in the circumferential direction of the inner tube 2 are provided.
In addition, about the width | variety of the louver 8, height, dimensions, such as a V-shaped angle, and arrangement | positioning, it can set suitably.

また、内管２の製造方法としては、内管２の素材となる金属製平板部材に切り起こし加工を施して予めルーバ８を形成した後、円筒状にしてその端縁同士を接合する。勿論、他の製造方法を用いても良い。 Moreover, as a manufacturing method of the inner tube | pipe 2, after giving and processing to the metal flat plate member used as the raw material of the inner tube | pipe 2 and forming the louver 8 previously, it makes cylindrical shape and joins the edges. Of course, other manufacturing methods may be used.

次に、作用を説明する。
このように構成された車両用消音器１では、内管２の排気ガス上流側端部５に図示を省略するエンジン側の接続管が接続される一方、排気ガス下流側端部６に図示を省略するメインマフラ側の接続管が接続される。 Next, the operation will be described.
In the vehicle silencer 1 configured in this way, an engine-side connection pipe (not shown) is connected to the exhaust gas upstream end 5 of the inner pipe 2, while the exhaust gas downstream end 6 is shown in the drawing. The connecting pipe on the main muffler side to be omitted is connected.

そして、内管２の排気ガス上流側端部５から排気ガスが流入して排気ガス下流側端部６へ流通する間に、排気ガスの音エネルギーが、各ルーバ８の小孔11a,11bを介して共鳴室３に進入することにより、共鳴作用を受けて減衰され、これによって、排気騒音を消音できる。 Then, while the exhaust gas flows from the exhaust gas upstream end 5 of the inner pipe 2 and flows to the exhaust gas downstream end 6, the sound energy of the exhaust gas passes through the small holes 11 a and 11 b of the louvers 8. By entering the resonance chamber 3 via the resonance chamber, the resonance chamber 3 is attenuated by receiving a resonance effect, and thus the exhaust noise can be silenced.

また、ルーバ８が略Ｖ字形に切り起こした形状に形成されるため、多指向性の排気ガスの放射エネルギーを共鳴室３に進入させることができ、外管４の放射音を防止できる。 In addition, since the louver 8 is formed in a substantially V-shaped shape, the radiant energy of multidirectional exhaust gas can enter the resonance chamber 3 and the radiated sound of the outer tube 4 can be prevented.

ここで、従来の発明にあっては、排気ガスの流速（流量）や小孔の径によって生じる異音（笛吹音）を防止することを目的としてルーバを設けているが、内管の径をさらに小さくして排気ガスの流速を大きくすると、ルーバを起因とする異音が発生してしまうという問題点があった。
なお、異音の原因は、排気ガスの流速が大きくなると内管の外側に設けられたルーバの排気ガス下流側の側壁に渦流が発生してしまうためと考えられる。 Here, in the conventional invention, a louver is provided for the purpose of preventing abnormal noise (flute blowing sound) caused by the exhaust gas flow velocity (flow rate) and the diameter of the small hole. If the exhaust gas flow rate is increased by further reducing the exhaust gas flow, there is a problem in that abnormal noise caused by the louver occurs.
The cause of the noise is considered to be that when the flow velocity of the exhaust gas is increased, a vortex is generated on the side wall on the downstream side of the exhaust gas of the louver provided outside the inner pipe.

これに対し、本実施例１では、前述したように、ルーバ８を内管２の内側へ向けて設けたため、渦流が発生する虞がなく、ルーバに起因する異音の発生を防止できる。
なお、ルーバ８の形状以外を同一条件とした従来品と本発明品の騒音試験を行った結果、従来品では内管の径を４０φよりも小さくすると異音が発生したのに対し、本発明品は内管２の径を３５φにしても異音が発生しなかった。 On the other hand, in the first embodiment, as described above, the louver 8 is provided toward the inner side of the inner tube 2, so that there is no possibility that vortex flow is generated, and generation of abnormal noise due to the louver can be prevented.
As a result of the noise test of the conventional product and the product of the present invention under the same conditions except for the shape of the louver 8, the conventional product produced abnormal noise when the diameter of the inner tube was smaller than 40φ. No abnormal noise was generated even when the diameter of the inner tube 2 was 35φ.

従って、本実施例１の車両用消音器１では、内管２の径を小さくして排気ガスの流速を大きくした場合でもルーバ８に起因する異音の発生を防止できる。 Therefore, in the vehicle silencer 1 of the first embodiment, even when the diameter of the inner pipe 2 is reduced and the flow rate of the exhaust gas is increased, it is possible to prevent the generation of noise caused by the louver 8.

次に、効果を説明する。
以上、説明したように、本実施例１の車両用消音器１にあっては、排気ガスが流通する直管状の内管２と、この内管２との間に共鳴室３を有して該内管２の外側に設けられる略円筒状の外管４とから構成され、内管２に一対の小孔11a,11bを有するルーバ８が設けられた車両用消音器１において、ルーバ８を内管２の内側へ向けて設けたため、内管２の径を小さくして排気ガスの流速を大きくした場合でもルーバ８に起因する異音の発生を防止できる。 Next, the effect will be described.
As described above, the vehicle silencer 1 according to the first embodiment has the straight tubular inner tube 2 through which the exhaust gas flows and the resonance chamber 3 between the inner tube 2. In the vehicle silencer 1, which is composed of a substantially cylindrical outer tube 4 provided outside the inner tube 2, and a louver 8 having a pair of small holes 11 a and 11 b is provided in the inner tube 2, the louver 8 is Since it is provided toward the inner side of the inner pipe 2, even when the diameter of the inner pipe 2 is reduced and the flow rate of the exhaust gas is increased, the generation of abnormal noise due to the louver 8 can be prevented.

また、ルーバ８を、略Ｖ字形に切り起こした形状としたため、異音の発生を防止しつつ、多指向性の排気ガスの放射エネルギーを共鳴室３に流入でき、外管４に対して斜めになるため、より外管４の放射音も低減し、好適となる。 Further, since the louver 8 has a substantially V-shaped shape, the radiation energy of the multidirectional exhaust gas can flow into the resonance chamber 3 while preventing the generation of abnormal noise, and is oblique to the outer tube 4. Therefore, the radiated sound of the outer tube 4 is also reduced, which is preferable.

以上、本実施例を説明してきたが、本発明は上述の実施例に限られるものではなく、本発明の要旨を逸脱しない範囲の設計変更等があっても、本発明に含まれる。
例えば、本実施例１で説明した各構成部材の詳細な部位の形状、寸法、材質、設置数、配置等を追加・変更したものは全て本発明の範疇となる。 Although the present embodiment has been described above, the present invention is not limited to the above-described embodiment, and design changes and the like within a scope not departing from the gist of the present invention are included in the present invention.
For example, all the additions and changes in the shape, size, material, number of installations, arrangement, and the like of the detailed portions of the constituent members described in the first embodiment are within the scope of the present invention.

本発明の実施例１の車両用消音器の内部を説明する図である。It is a figure explaining the inside of the silencer for vehicles of Example 1 of the present invention. 図１のＳ２−Ｓ２線における断面図である。It is sectional drawing in the S2-S2 line | wire of FIG. 本実施例１のルーバの拡大図である。It is an enlarged view of the louver of the first embodiment. 図３のＳ４−Ｓ４線における断面図である。It is sectional drawing in the S4-S4 line | wire of FIG. 図３のＳ５−Ｓ５線における断面図である。It is sectional drawing in the S5-S5 line | wire of FIG.

Explanation of symbols

１車両用消音器
２内管
３共鳴室
４外管
５（内管の）排気ガス上流側端部
６（内管の）排気ガス下流側端部
７金属製メッシュ部材
８ルーバ
９、１０側壁
１１ａ、１１ｂ小孔 DESCRIPTION OF SYMBOLS 1 Vehicle silencer 2 Inner pipe 3 Resonance chamber 4 Outer pipe 5 (Inner pipe) Exhaust gas upstream end 6 (Inner pipe) Exhaust gas downstream end 7 Metal mesh member 8 Louver 9, 10 Side wall 11a 11b Small hole

Claims

It is composed of an inner pipe through which exhaust gas flows, and an outer pipe provided outside the inner pipe with a resonance chamber between the inner pipe,
In the vehicle silencer provided with a louver having a pair of small holes in the inner tube,
A muffler for a vehicle, wherein the louver is provided toward the inner side of the inner pipe.