DE102018218796A1 - HELMHOLTZ MUFFLERS FOR VEHICLES - Google Patents

Abstract

A Helmholtz muffler for a vehicle can have a muffler housing with an interior divided into several expansion chambers; a resonance chamber hermetically formed in a vehicle body part; and have a connecting pipe configured to be connected to one of the expansion chambers of the muffler housing and to the resonance chamber.

Description

BACKGROUND OF THE INVENTION

Technical field

The present invention relates to a Helmholtz muffler for a vehicle, and in particular to a Helmholtz muffler for a vehicle with a novel design in which a vehicle body part that supports a vehicle body is used as a resonance chamber.

Description of the Prior Art

In general, an exhaust system for a vehicle includes an exhaust manifold of an engine, an exhaust pipe connected to the exhaust manifold and extending to a rear of the vehicle body, a catalytic converter for cleaning exhaust gas attached to a predetermined position of the exhaust pipe, and a silencer, which is mounted on an end portion of the exhaust pipe to attenuate the exhaust noise.

1 12 is a cross-sectional view showing a conventional Helmholtz silencer for a vehicle.

The silencer has a housing 10 with a predetermined volume, at least three or more guide plates 15 . 16 . 17 that in an interior of the silencer housing 10 are arranged in a longitudinal direction and spaced from each other around the interior of the muffler housing 10 in several expansion chambers 11 . 12 . 13 and a resonance chamber 14 to divide an inner tube 18 that through each of the baffles 15 . 16 and 17 goes through and is connected to them and in the muffler housing 10 is arranged in the longitudinal direction thereof, a connecting pipe 19 that between the baffles 15 and 16 is connected, and at least two or more outer pipes 20 through each of the baffles 15 . 16 and 17 go through and connected to it and in the muffler housing 10 is arranged in the longitudinal direction thereof.

At the same time is an outlet pipe 22 with an inlet end portion of the inner tube 18 connected, and an outlet end portion of the inner tube 18 is in the sealed resonance chamber 14 arranged.

Furthermore, there is an inlet end portion of the outer tube 20 in the first expansion chamber 11 arranged, and an outlet end portion of the outer tube 20 , which is a portion through which the exhaust gas is last discharged, is arranged in a state in which it passes through the resonance chamber 14 passes through and is released to the outside.

How to get out 2A sees, have the first guide plate 15 and the second baffle 16 of the guide plates 15 . 16 . 17 several perforations formed in it 21 on, and the third baffle 17 is designed so that it has no perforation, as in 2 B is shown.

Hence the first expansion chamber 11 and the second expansion chamber 12 through the perforations 21 the first guide plate 15 connected with each other, the second expansion chamber 12 and the third expansion chamber 13 stand by the perforations 21 the second guide plate 16 in communication with each other, and the third expansion chamber 13 and the first expansion chamber 11 stand by the perforations 21 of the first and second guide plates 15 and 16 with each other and are simultaneously connected to each other by means of the connecting pipe 19 in connection.

On the other hand, the third guide plate 17 has a closed configuration, in which no perforation is formed, is the resonance chamber 14 formed as a sealed space and receives exhaust gas from the outlet end portion of the inner tube 18 is emitted to function as a Helmholtz resonator that reduces noise in the low-frequency range.

Meanwhile, in a section between the second baffle 16 and the third guide plate 17 runs in the entire length of the inner tube 18 multiple perforations 18 - 1 educated.

Therefore, if exhaust gas from the exhaust pipe 22 into the inner tube 18 is discharged, exhaust gas is continuously discharged by a method in which exhaust gas is in the third expansion chamber 13 about the perforations 18 - 1 of the inner tube flows and is released into this, a process in which exhaust gas from the third expansion chamber 13 about the perforations 21 the second guide plate 16 into the second expansion chamber 12 is a method in which exhaust gas from the second expansion chamber 12 about the perforations 21 the first guide plate 15 into the first expansion chamber 11 released and at the same time from the third expansion chamber 13 over the connecting pipe 18 into the first expansion chamber 11 is discharged and a method in which exhaust gas from the first expansion chamber 11 through the outer tube 20 flows and is then released to the outside.

While the exhaust gas that is in the inner tube 18 flows sequentially through the third expansion chamber 13 , the second expansion chamber 12 and the first expansion chamber 11 flows, as described above, exhaust noise (exhaust noise except for the low frequency component in the whole of the speed range of an engine) is reduced.

In the inner tube 18 flowing exhaust gas is also through the outlet end portion of the inner pipe 18 into the resonance chamber 14 delivered and included. In the resonance chamber 14 the noise of the low-frequency component in the exhaust gas noise, which is unpleasant for a human ear, is reduced.

However, the conventional silencer described above has the following problems.

First, the Helmholtz resonance chamber, which is formed together with several expansion chambers that divide an interior of the muffler into several sections, aims to reduce the noise at a certain frequency (noise within the low frequency range). However, it is difficult to change factors (Helmholtz resonance frequency, etc.) that determine the resonance frequency, so there is a limitation in the reduction of low-frequency noise, which is a target reduction range.

Second, when a capacity (volume) of the resonance chamber in the muffler is increased, noise reduction within the low frequency range can be enhanced. However, as the resonance chamber capacity increases, the size of the muffler housing of the muffler increases, so that complicated procedures, such as a change in the design of an exhaust system, can follow. Furthermore, if the capacity of the resonance chamber is increased without increasing the size of the muffler housing of the muffler, the capacity of the expansion chamber is reduced in inverse proportion to the capacity of the resonance chamber, and therefore there is a problem that a noise reduction effect achieved by the expansion chamber is within the entire speed range is inevitably reduced.

The information disclosed in this section of the invention only serves to improve the understanding of the general background of the invention and cannot be interpreted as confirmation or as a form of an indication that this information forms the prior art which is already known to the person skilled in the art.

PRESENTATION OF THE INVENTION

Various aspects of the present invention are directed to the provision of a Helmholtz muffler for a vehicle with a novel design, in which an interior of a housing of the muffler is divided into a plurality of sections used as expansion chambers, and a hollow vehicle body part is connected and in Connection to the muffler housing of the muffler to be used as a resonance chamber, so that both a capacity (volume) of the resonance chamber and a capacity of the expansion chambers can be increased, which has a noise reduction effect within the entire speed range obtained by the expansion chambers, and also enhances an effect of noise reduction within the low frequency range obtained by the resonance chamber.

In various aspects of the present invention, various aspects of the present invention provide a Helmholtz muffler for a vehicle that has a muffler housing with an interior that is divided into a plurality of expansion chambers; a resonance chamber hermetically formed in a vehicle body part; and a connecting pipe configured to be connected to one of the expansion chambers of the muffler housing and to the resonance chamber.

Partitions can be arranged on both sides of the resonance chamber, by means of which a capacity of the resonance chamber is determined. Here, the partitions can be integrally welded to a vehicle body part.

The connecting pipe may be connected to and communicate with the expansion chamber among the plurality of expansion chambers, to which exhaust gas is finally discharged.

A bellows tube that can be moved vertically and horizontally can be used as the connecting pipe to absorb a shift in the behavior of the muffler housing, and an upper end portion and a lower end portion of the bellows tube can be welded to the vehicle body part and the muffler housing, respectively.

Further, a first baffle and a second baffle may be mounted in a muffler housing in a longitudinal direction and spaced apart to form a space between a side wall of the muffler housing and the first baffle as a first expansion chamber to form a space between the first Form guide plate and the second guide plate as a second expansion chamber, and to form a space between the other side wall of the muffler housing and the second guide plate as a third expansion chamber.

Further, an inner tube that passes through the first baffle and the second baffle may be disposed in the muffler housing, and an exhaust pipe is connected to an inlet end portion of the inner tube, and an outlet end portion of the inner tube is disposed in the third expansion chamber.

An outer tube, which runs through the first guide plate and the second guide plate, can also be arranged in the silencer housing. Here, an inlet end portion of the outer pipe may be arranged in the first expansion chamber, and an outlet end portion may be arranged to pass through the other side wall of the muffler housing and to be exposed to the outside.

Furthermore, a connecting pipe, which is designed such that the first expansion chamber and the third expansion chamber are connected to one another, can be connected between the first guide plate and the second guide plate.

Furthermore, a plurality of perforations of the entire length region of the inner tube can be formed in a section which is arranged in the third expansion chamber.

Other aspects and exemplary embodiments of the disclosure are discussed below.

It is understood that the term "vehicle" or "vehicle" or other similar term as used herein includes motor vehicles in general, such as automobiles, including sports utility vehicles (SUVs), buses, trucks, various commercial vehicles, watercraft including a variety of boats and ships, airplanes, and the like, and include hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles, and other alternative fuel vehicles (e.g., fuels made from others Sources obtained as petroleum). A hybrid vehicle referred to here is therefore a vehicle that has two or more energy sources, for example vehicles with both a gasoline engine and an electrically operated drive. The above and other features of the disclosure are discussed below.

The methods and apparatus of the present invention have other features and advantages that are apparent from, or set forth in, the accompanying drawings, which are incorporated herein and the following detailed description, which together serve to explain certain principles of the present invention.

list of figures

• 1 Fig. 12 is a cross-sectional view showing a conventional Helmholtz silencer for a vehicle;
• 2A and 2 B are front views showing a configuration of a baffle that defines expansion chambers in the silencer;
• 3 11 is a perspective view exemplifying a Helmholtz silencer for a vehicle according to an exemplary embodiment of the present invention.
• 4 14 is a cross-sectional view exemplifying the Helmholtz silencer for a vehicle according to an exemplary embodiment of the present invention;
• 5 FIG. 14 is a cross-sectional view exemplifying an exhaust gas flow in the Helmholtz silencer for a vehicle according to an exemplary embodiment of the present invention;
• 6 FIG. 14 is a cross-sectional view for comparing a state before a reduction in the case capacity of the Helmholtz silencer for a vehicle according to an exemplary embodiment of the present invention with a state after a decrease in the case capacity; FIG. and
• 7 12 is a view showing another exemplary embodiment of a configuration for connecting a bellows pipe of the Helmholtz muffler for a vehicle according to an exemplary embodiment of the present invention.

It should be understood that the accompanying drawings are not necessarily to scale and are a somewhat simplified illustration of various features that illustrate the basic principles of the invention. The specific design features of the present invention, as included herein, including, for example, certain dimensions, orientations, positions, and shapes, are determined in part by the particular intended application and use environment.

In the figures, reference numerals refer to the same or equivalent parts of the present invention in the different figures of the drawing.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Reference will now be made in detail to various embodiments of the present invention (s), examples of which are illustrated in the accompanying drawings and described below. While the invention will be described in connection with exemplary embodiments, it is to be understood that the present description is not intended to limit the invention to these exemplary embodiments. On the other hand, the invention (s) are intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which are included in the spirit and scope of the invention as defined by the appended claims could be.

Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings, so that those skilled in the art to which the present invention relates can easily practice the present invention. Because the present invention can be implemented in various forms, the present invention is not limited to the exemplary embodiments described herein.

Throughout the description, it is understood that if a component is referred to as “having”, it does not exclude other components, but can further have the other components unless otherwise stated.

In order to clearly describe the present invention, parts not related to the description are omitted, and the same reference numerals are used to indicate the same or similar components in the drawings and the detailed description.

3 and 4 14 are views illustrating a Helmholtz muffler for a vehicle according to an exemplary embodiment of the present invention, and reference numeral “300” denotes a vehicle body part that supports a vehicle body.

The vehicle body part 300 is a side part that is arranged in a longitudinal direction of a vehicle body or a transverse part that is arranged in a width direction of the vehicle body, and is provided in the form of a beam with a hollow square cross section.

The main feature of the present invention is that the vehicle body part 300 can be designed so that it is used as a resonance chamber of the silencer.

In other words, although the conventional muffler is constructed to have a configuration in which an interior of a case is divided into three expansion chambers and a resonance chamber is divided by three baffles, the muffler of the present invention is characterized in that an interior of a case 100 is divided into two expansion chambers by two guide plates, and an interior of the vehicle body part 300 can be used as a resonance chamber.

To this end, the muffler of the present invention has the muffler housing 100 , which is designed so that its interior can be divided into three expansion chambers by two baffles, a resonance chamber 310 that are hermetic in the vehicle body part 300 is formed, a connecting pipe 200 that between one of three divided expansion chambers in the silencer housing 100 is connected, and the resonance chamber 310 , and the like, on.

Because the entire interior of the vehicle body part 300 is too large to be used as a resonance chamber, a capacity (volume) necessary for the resonance chamber 310 is required in the interior of the vehicle body part 300 be provided.

To determine the capacity (volume) only for the resonance chamber 310 in the interior of the vehicle body part 300 partition walls are required 312 and 314 at predetermined positions on both sides of the resonance chamber 310 arranged, and each of the partitions 312 and 314 is integral with an inner surface of the vehicle body part 300 welded.

Therefore, a space consisting of upper, lower, right and left surfaces of the vehicle body part 300 and the partitions 312 and 314 exists as a resonance chamber 310 used.

In the silencer housing 100 of the present invention are a first baffle 111 and a second baffle 112 attached so that they are spaced apart from each other by a predetermined distance in their longitudinal direction.

Therefore, one acts between a side wall of the muffler housing 100 and the first guide plate 111 formed space as the first expansion chamber 101 , a space between the first guide plate 111 and the second guide plate 112 acts as a second expansion chamber 102 , and a space between the other side wall of the muffler housing 100 and the second guide plate 112 acts as a third expansion chamber 103 ,

At the same time, each of the first guide plates 111 and the second guide plate 112 several perforations formed in it 113 on.

Also penetrates an inner tube 120 the first guide plate 111 and the second baffle 112 in the silencer housing 100 and is in the longitudinal direction of the muffler housing 100 arranged, and an inlet end portion of the inner tube 120 is with an outlet pipe 130 connected and an outlet end portion of the inner tube 120 is in the third expansion chamber 103 arranged to be configured to discharge exhaust gas.

There are several perforations at the same time 122 for discharging the exhaust gas in a range of the entire length of the inner tube 120 formed which in the third expansion chamber 103 is trained.

In the silencer housing 100 also pass through two outer tubes 140 the first guide plate 111 and the second baffle 112 and are arranged in the longitudinal direction of the muffler housing, an inlet end portion of the outer pipe 140 is in the first expansion chamber 101 arranged to allow the intake of exhaust gas, and an outlet end portion of the outer tube 140 is arranged to pass through the other wall of the muffler housing 100 to go through and be exposed to the outside.

For reference, as in 3 shown is a separate muffler cover 142 at the outlet end portion of the outer tube 140 attached to improve the aesthetics of the external appearance.

There is also a connecting pipe 150 , which is designed so that the first expansion chamber 101 directly with the third expansion chamber 103 communicates between the first guide plate 111 and the second guide plate 112 connected.

According to an exemplary embodiment of the present invention, the third expansion chamber 103 which is the expansion chamber into which the exhaust gas is last discharged from three separate expansion chambers 101 . 102 . 103 in the silencer housing 100 to the resonance chamber 310 by means of the connecting pipe 200 connected so that the third expansion chamber and the resonance chamber communicate with each other.

A bellows pipe 202 that can be moved vertically and horizontally is called the connecting pipe 200 used to shift the behavior of the muffler housing 100 absorb, which is caused by vehicle vibrations.

At this time, there are an upper end portion and a lower end portion of the bellows pipe 202 to the vehicle body part 300 or the silencer housing 100 welded so that the inside of the bellows tube 202 is hermetically sealed to prevent exhaust gas from escaping.

In the following, reference will be made to the operational sequence of the Helmholtz silencer of the present invention with the configuration described above.

If exhaust gas from the exhaust pipe 130 into the inner tube 120 Exhaust gas is discharged continuously through a process in which exhaust gas enters the third expansion chamber 103 over that in the outlet end portion of the inner tube 120 trained perforations 122 is a process in which exhaust gas from the third expansion chamber 130 over the perforations of the second guide plate 112 into the second expansion chamber 102 is a process in which exhaust gas from the second expansion chamber 102 over the perforations of the first guide plate 111 into the first expansion chamber 101 released and at the same time from the third expansion chamber 103 over the connecting pipe 150 into the first expansion chamber 111 is discharged, and a process in which exhaust gas from the first expansion chamber 111 through the outer tube 140 flows and is then released to the outside.

While the exhaust gas that is in the inner tube 120 flows sequentially through the third expansion chamber 103 , the second expansion chamber 102 and the first expansion chamber 101 flows, exhaust emission noises (exhaust noise except for the low frequency component in the whole of the speed range of an engine) are reduced.

If in the inner tube 120 flowing exhaust gas into the third expansion chamber 103 through the in the outlet end portion of the inner tube 120 trained perforations 122 is released, exhaust gas also becomes a resonance chamber 310 through the bellows pipe 202 which is the connecting pipe 200 is, by means of the bellows tube 202 dispensed and then enclosed since the third expansion chamber with the resonance chamber 310 is connected, which in the vehicle body part 300 is trained. In the resonance chamber 310 At this time, the noise of the low-frequency component in the exhaust noise, which is uncomfortable for a human ear, is reduced.

There, as described above, the interior of the muffler housing 100 is used only for the expansion chambers, which divides the interior into three sections and the hollow vehicle body part 300 as a resonance chamber 310 used with the third expansion chamber 103 is connected, both the capacity (volume) of the resonance chamber and a capacity of the expansion chamber can be increased, so that it is possible to have an effect of noise reduction within the entire speed range caused by the expansion chamber and an effect of noise reduction within the low frequency range to amplify, which is caused by the resonance chamber formed in the vehicle body part.

It is also possible to reduce the noise within the low-frequency range in the vehicle body part 300 trained resonance chamber 310 the positions of the partition walls can be reduced, however, if it is necessary to further lower a low-frequency resonance frequency 312 and 314 that are on both sides of the resonance chamber 310 welded, moved to the outside to increase the volume of the resonance chamber, or by using a bellows tube with a smaller internal cross-sectional area than the bellows tube 202 , the resonance frequency can be lowered to reduce exhaust noise, and thus an effect of reducing noise within the low frequency range can be further improved.

By forming the resonance chamber 310 in the vehicle body part 300 instead of the muffler housing, it is also as in 6 shown, possible, the volume (capacity) of the third expansion chamber 103 in the silencer housing 100 to reduce, which reduces the size of the muffler housing. It is therefore possible to ensure a design space for components of an exhaust system and at the same time to reduce the manufacturing costs of the silencer housing.

It is also possible to fit the bellows tube of the Helmholtz silencer for a vehicle according to an exemplary embodiment of the present invention with the resonance chamber 310 of the vehicle body part 300 to attach to a thread.

Around the bellows pipe 202 with the silencer housing 100 and the resonance chamber 310 in the vehicle body part 300 on related as in 7 shown to connect are the lower end portion of the bellows tube 202 with the silencer housing 100 welded and an external thread section 204 is formed on an upper end portion of the bellows tube.

Furthermore, there is a second external thread section 316 formed to be on a lower surface of an outer surface of the resonance chamber 310 in the vehicle body part 300 protrudes.

At the time is a stopper 205 to complete a fastening nut 318 and to prevent the fastening nut from lowering 318 further integrally at a lower end portion of an outer peripheral portion of the first male thread portion 204 educated.

In the present embodiment, the first male thread section 204 and the second male thread section 316 through the mounting nut 318 attached to each other so that a connection of the bellows pipe 202 with the resonance chamber 310 in the vehicle body part 300 is achieved.

The fastening nut 318 is preferably on the second external thread section 316 attached to the bottom surface of the resonance chamber 310 is trained to the fastening nut 318 at an uppermost area of the second external thread section 316 to position, and the first male thread section 204 of the bellows tube 202 is then in close contact with the second male thread section 316 brought. As such, the mounting nut 318 rotated by a screw and to the first male thread section 204 moves, which is positioned under the second male thread portion, so that the first male thread portion 204 and the second male thread section 316 the mounting nut 318 share and achieve a fortified state.

The fastening nut is at the same time 318 coupled until they stop 205 touches, which is formed on a lower end portion of the first male thread portion.

Therefore share the first male thread section 204 and the second male thread section 316 the mounting nut 318 to be attached to each other. As a result, there is a connection of the bellows pipe 202 with the resonance chamber 310 in the vehicle body part 300 completed.

The present invention described above provides the following effects.

First, using the interior of the muffler housing of the muffler only as the expansion chambers dividing the interior into several sections and using the hollow vehicle body part as a resonance chamber connected to one of the expansion chambers, the capacity (volume) of the resonance chamber and the Capacity of the expansion chambers can be increased, so that it is possible to enhance the effect of noise reduction within the entire speed range obtained by the expansion chambers and the effect of noise reduction within the low frequency range obtained by the resonance chamber formed in the vehicle body part becomes.

Second, since the muffler housing can be applied to a housing of reduced size, it is possible to ensure design space for components of the exhaust system and to reduce the manufacturing cost of the muffler housing.

To simplify the explanation and precise definition in the appended claims, the terms "upper", "lower", "inner", "outer", "upper", "lower", "upper", "lower", "lower", "Higher", "inside", "outside", "inside", "outside", "inside" "outside", "inside", "outside", "inside", "outside", " forward ”and“ backward ”are used to describe features of the exemplary embodiments with respect to the locations of such features as shown in the figures.

The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments have been selected and described to explain certain principles of the invention and their practical application to enable others skilled in the art to make and use various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. The scope of the invention is intended to be defined by the appended claims and their equivalents.

Claims (15)

Helmholtz silencer for a vehicle, the silencer comprising: a silencer housing with an interior divided into several expansion chambers; a resonance chamber hermetically formed in a vehicle body part; and a connecting pipe, which is connected to at least one of the several expansion chambers of the silencer housing and to the resonance chamber. Helmholtz silencer for the vehicle after Claim 1 , partition walls, by which a capacity of the resonance chamber is determined, are respectively arranged on a first side and a second side of the resonance chamber, and the partition walls are integrally attached to the vehicle body part to form the resonance chamber. Helmholtz silencer for the vehicle after Claim 1 or 2 , wherein the connecting pipe is connected to an expansion chamber from the plurality of expansion chambers, into which exhaust gas is last discharged from the muffler housing, and is in fluid communication. Helmholtz muffler for a vehicle according to one of the preceding claims, wherein the connecting tube is a bellows tube, which is designed to be movable according to the movement of the muffler housing. Helmholtz silencer for the vehicle after Claim 4 , wherein an upper end portion and a lower end portion of the bellows pipe are fixed to the resonance chamber in the vehicle body part and the muffler housing, respectively. A Helmholtz silencer for a vehicle according to any one of the preceding claims, further comprising: a first baffle and a second baffle mounted in the muffler housing in a longitudinal direction and spaced apart from each other to form a space between a first side wall of the muffler housing and the first baffle as a first expansion chamber among the plurality of expansion chambers to form a space between the first To form the baffle and the second baffle as a second expansion chamber among the plurality of expansion chambers, and to form a space between a second side wall of the muffler housing and the second baffle as a third expansion chamber among the plurality of expansion chambers. Helmholtz silencer for the vehicle after Claim 6 further comprising: an inner tube that passes through the first baffle and the second baffle and is disposed in the muffler housing, and an exhaust pipe that is disposed outside the muffler housing and is connected to a first end portion of the inner tube, a second end portion of the inner tube is arranged in the third expansion chamber. Helmholtz silencer for the vehicle after Claim 6 or 7 further comprising: at least one outer tube that extends through the first baffle and the second baffle and is disposed in the muffler housing, wherein a first end portion of the at least one outer tube is disposed in the first expansion chamber and a second end portion thereof is disposed to be runs through the second side wall of the muffler housing and is exposed outside the muffler housing. Helmholtz silencer for the vehicle after Claim 7 or 8th wherein a plurality of perforations are formed in the first end portion of the at least one outer tube. Helmholtz silencer for the vehicle after Claim 8 or 9 further comprising: a muffler cover attached to the second end portion of the at least one outer tube. Helmholtz silencer for the vehicle according to one of the Claims 6 to 10 , further comprising: a connecting pipe which runs through the first guide plate and the second guide plate and fluidly connects the first expansion chamber and the third expansion chamber in order to be in fluid communication with one another. Helmholtz silencer for the vehicle according to one of the Claims 7 to 11 , wherein a plurality of perforations are formed in a portion under an entire length range of the inner tube, and wherein the portion of the inner tube is arranged in the third expansion chamber. Helmholtz silencer for the vehicle according to one of the Claims 6 to 12 , wherein a plurality of perforations are formed on the first guide plate and the second guide plate. Helmholtz silencer for the vehicle according to one of the Claims 4 to 13 wherein the bellows tube has a first male threaded portion formed at an upper end portion thereof, the resonance chamber in the vehicle body part has a second male threaded portion formed on an outer surface thereof, and the first male threaded portion and the second threaded portion are fastened together by a fastening nut are attached to connect the bellows tube to the resonance chamber in the vehicle body part. Helmholtz silencer for the vehicle after Claim 14 wherein the first male threaded portion further includes a stopper integrally formed on a lower end portion of an outer peripheral portion of the first male threaded portion to guide completion of the fastening nut and prevent the fastening nut from lowering.

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