U.S. patent application number 17/373031 was filed with the patent office on 2022-01-20 for muffler of an exhaust system.
The applicant listed for this patent is Faurecia Emissions Control Technologies, Germany GmbH. Invention is credited to Michael Thome.
Application Number | 20220018272 17/373031 |
Document ID | / |
Family ID | 1000005763101 |
Filed Date | 2022-01-20 |
United States Patent
Application |
20220018272 |
Kind Code |
A1 |
Thome; Michael |
January 20, 2022 |
MUFFLER OF AN EXHAUST SYSTEM
Abstract
A muffler for an exhaust system of a vehicle comprises an outer
housing in an interior of which a Helmholtz chamber is formed. A
feed body has an opening fluidically connected to the Helmholtz
chamber. At least two exhaust pipes extend at least in sections
within the outer housing, are spaced apart from each other, and
form a flow path for an exhaust gas through the outer housing. The
exhaust pipes each have at least two exhaust pipe sections which
are entirely spaced apart from each other by a gap in one flow
direction of the exhaust gas. The feed body surrounds the exhaust
pipes over an entire circumference in a region of the gaps and
fluidically connects the exhaust pipes to the Helmholtz
chamber.
Inventors: |
Thome; Michael; (Augsburg,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Faurecia Emissions Control Technologies, Germany GmbH |
Augsburg |
|
DE |
|
|
Family ID: |
1000005763101 |
Appl. No.: |
17/373031 |
Filed: |
July 12, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F01N 13/08 20130101;
F01N 1/023 20130101; F01N 2450/22 20130101 |
International
Class: |
F01N 1/02 20060101
F01N001/02; F01N 13/08 20060101 F01N013/08 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 15, 2020 |
DE |
10 2020 118 749.1 |
Claims
1. A muffler for an exhaust system of a vehicle, comprising: an
outer housing in an interior of which a Helmholtz chamber is
formed; a feed body which has an opening fluidically connected to
the Helmholtz chamber and forms a neck of a Helmholtz resonator
comprising the Helmholtz chamber; and at least two exhaust pipes
which extend at least in sections within the outer housing, are
spaced apart from each other, and which form a flow path for an
exhaust gas through the outer housing; wherein the at least two
exhaust pipes each have at least two exhaust pipe sections which
are entirely spaced apart from each other by a gap in one flow
direction of the exhaust gas, and wherein the feed body surrounds
the at least two exhaust pipes over an entire circumference in a
region of the gaps and fluidically connects the at least two
exhaust pipes to the Helmholtz chamber.
2. The muffler according to claim 1, wherein the at least two
exhaust pipes extend parallel to each other in the interior of the
outer housing.
3. The muffler according to claim 1, wherein the at least two
exhaust pipes extend in a linear manner through the outer
housing.
4. The muffler according to claim 1, wherein the at least two
exhaust pipes extend in a curved manner through the outer
housing.
5. The muffler according claim 1, wherein the feed body has two
half-shells which together surround the at least two exhaust
pipes.
6. The muffler according claim 1, wherein the feed body is
connected to the exhaust pipe sections by an intermaterial
bond.
7. The muffler according claim 1, wherein the feed body has two
annular sections, each annular section surrounding the gap.
8. The muffler according to claim 7, wherein the feed body has a
feed section which extends from both annular sections, opens into
the Helmholtz chamber, and extends between the at least two exhaust
pipes.
9. The muffler according to claim 8, wherein the feed section
extends parallel to a flow direction of the exhaust gas in the at
least two exhaust pipes.
10. The muffler according claim 1, wherein the Helmholtz chamber is
delimited at least in sections by an inner envelope surface of the
outer housing.
11. The muffler according claim 1, wherein a partition wall which
delimits the Helmholtz chamber in sections and separates a further
muffler chamber in the interior of the outer housing from the
Helmholtz chamber is arranged within the outer housing.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a U.S. non-provisional application
claiming the benefit of German Application No. 10 2020 118 749.1,
filed on Jul. 15, 2020, which is incorporated herein by reference
in its entirety.
TECHNICAL FIELD
[0002] The disclosure relates to a muffler for an exhaust system of
a vehicle.
BACKGROUND
[0003] Mufflers for exhaust systems are known in different
designs.
[0004] To achieve the maximum possible broadband attenuation, both
the functional principle of absorption and that of reflection are
used, among others, which are for example realized in separate
chambers within a single outer housing of the muffler.
[0005] To additionally attenuate low frequencies, a further chamber
may be provided as part of a Helmholtz resonator in mufflers. The
latter can be designed as a so-called branch resonator, in which a
resonator chamber, also known as a Helmholtz chamber, is connected
to the tube through which the exhaust gas flows via a resonator
tube which forms the neck of the Helmholtz resonator.
[0006] Such a Helmholtz resonator attenuates a precisely defined
frequency, namely the resonance frequency thereof which depends,
among other things, on the volume of the Helmholtz chamber, the
length of the neck, and the cross-sectional area of the neck. Thus,
in order to adapt the sound attenuation by the Helmholtz resonator
to a specific engine or engine type, one or more of the parameters
mentioned can be varied in a purposeful manner
[0007] Depending on the engine type, it may also be provided that
the exhaust system includes two exhaust pipes which guide the
exhaust gases from the engine to a tailpipe of the exhaust system.
Two separate Helmholtz chambers are then formed in a muffler having
two exhaust pipes. Each exhaust pipe is connected to the
corresponding Helmholtz chamber via an appropriate opening in the
exhaust pipe and an appropriate feed body. This leads to bulky
mufflers.
[0008] The disclosure simplifies the structure of a muffler for an
exhaust system having two exhaust pipes.
SUMMARY
[0009] A muffler for an exhaust system of a vehicle includes an
outer housing in an interior of which a Helmholtz chamber is
formed, a feed body, and two exhaust pipes. The feed body has an
opening fluidically connected to the Helmholtz chamber and forms a
neck of a Helmholtz resonator comprising the Helmholtz chamber. The
exhaust pipes extend at least in sections within the outer housing,
are spaced apart from each other, and form a flow path for an
exhaust gas through the outer housing. The exhaust pipes each have
at least two exhaust pipe sections which are entirely spaced apart
from each other by a gap in one flow direction of the exhaust gas.
The feed body surrounds the exhaust pipes over an entire
circumference in the region of the gaps and fluidically connects
the exhaust pipes to the Helmholtz chamber.
[0010] The disclosure is based on the basic idea to form a common
feed body and thus a common neck and a common Helmholtz chamber for
the two exhaust pipes, i.e. a Helmholtz resonator for both exhaust
pipes. In this way, the structure of the muffler is simplified.
Furthermore, the exhaust pipe sections are spaced apart from each
other in the direction of the flow path of the exhaust gas through
the exhaust pipes, such that a simple fluidic connection is
established between the feed body and the exhaust pipes. In
particular, no additional holes have to be cut or punched into the
tubes forming the exhaust pipe.
[0011] The exhaust pipe sections are thus completely separated and
spaced apart from each other and accordingly have a certain
distance with respect to each other.
[0012] The distance of the exhaust pipe sections with respect to
each other is, for example, adapted to a resonance frequency to be
attenuated by the Helmholtz resonator.
[0013] One aspect of the disclosure provides that the exhaust pipes
extend parallel to each other. A compact structure of the muffler
is thus possible.
[0014] Alternatively or additionally, the exhaust pipes may extend
in a linear or curved manner through the outer housing. The muffler
can thus be mounted at any place along the exhaust system as it can
simply be adapted to a predetermined course of the exhaust
pipes.
[0015] To permit a simple mounting of the feed body, the feed body
may have two half-shells which together surround the exhaust pipes.
In the region of the gaps, the half-shells are placed onto the
exhaust pipe sections and connected to each other from opposite
sides which run transversely to the flow path of the exhaust
gas.
[0016] The shape and volume of the feed body, i.e. the shape of the
half-shells, may be adapted to a resonance frequency to be
attenuated. In this way, it is possible to attenuate a specific
frequency.
[0017] The length of the feed body and/or the cross-section of the
feed body is adapted to the resonance frequency, for example.
[0018] In one design of the disclosure, the feed body is connected
to the exhaust pipe sections by an intermaterial bond. The feed
body is thus firmly positioned in a specific place along the
exhaust pipe.
[0019] The feed body is fastened to the exhaust pipe sections by
welding or soldering, for example. These fastening types have a
good heat resistance.
[0020] The feed body may have two annular sections, each annular
section surrounding a gap. In this way, the annular section only
has very little influence on the flow behavior of the exhaust gas
from the gap into the feed body.
[0021] On the inside, the annular sections have a larger
cross-section than the exhaust pipes, such that an annular space is
additionally produced radially outside the gap, into which exhaust
gas from the gap can escape and can flow into the feed body.
[0022] In one design of the disclosure, the feed body has a feed
section which extends from both annular sections, opens into the
Helmholtz chamber, and extends between the exhaust pipes.
[0023] In other words, the space between the exhaust pipes is used
for the feed body. In this way, a very compact muffler can be
provided.
[0024] The feed section is tubular, for example.
[0025] The outer surfaces of the exhaust pipes in particular form
part of the feed body in the region of the feed section. The
cross-section of the feed body is thus also influenced by the
distance between the exhaust pipes. This distance is adapted to the
resonance frequency to be attenuated, for example.
[0026] For example, the feed section is delimited in sections by
two tab-shaped projections on the half-shells which extend from the
annular sections and each rest on both exhaust pipes so as to act
as bridges between the exhaust pipes. The neck of the Helmholtz
resonator is thus delimited by the exhaust pipe wall and the
tab-shaped projections.
[0027] The feed section may extend parallel to the flow direction
of the exhaust gas in the exhaust pipes. In this way, the area
between the exhaust pipes can preferably, even completely, be used
for the feed body. The structure of the muffler is thus further
simplified, and the weight thereof is reduced.
[0028] In one embodiment, the Helmholtz chamber is delimited at
least in sections by an inner envelope surface of the outer
housing. In this way, the resonance frequency of the Helmholtz
resonator can be adjusted directly by the geometrical shape of the
outer housing.
[0029] A partition wall may be arranged within the outer housing,
which delimits the Helmholtz chamber in sections and separates a
further muffler chamber in the interior of the outer housing from
the Helmholtz chamber. Therefore, different techniques can be used
in the muffler to attenuate the sound emissions. An effective
attenuation of the sound emissions is thus ensured.
[0030] It is also conceivable that more than one partition wall,
for example two or three partition walls are arranged within the
outer housing. In this way, the volume of the Helmholtz chamber can
simply be adapted for different engine versions or to frequencies
or frequency spectra to be attenuated.
[0031] The further muffler chamber is an absorption or reflection
chamber, for example.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] Further features and advantages of the disclosure will
become apparent from the description below and from the
accompanying drawings to which reference is made below and in
which:
[0033] FIG. 1 shows a schematic lateral view of a vehicle having a
muffler according to the disclosure,
[0034] FIG. 2 shows the muffler of FIG. 1 in a top view with one
half of the outer housing removed,
[0035] FIG. 3 shows a sectional view of the muffler along the
cutting line in FIG. 2, and
[0036] FIG. 4 shows a sectional view of the muffler along the
cutting line IV-IV in FIG. 2.
DETAILED DESCRIPTION
[0037] FIG. 1 shows a vehicle 10, here a motor vehicle. The vehicle
10 is a passenger car, for example.
[0038] The vehicle 10 includes an internal combustion engine 12 and
an exhaust system 14. A muffler 16 is arranged in the exhaust
system 14. The exhaust system 14 guides an exhaust gas produced in
the internal combustion engine 12 through the muffler 16 to an end
of the exhaust system 14, here to a tailpipe 17. The sound
emissions produced by the combustion process taking place in the
internal combustion engine 12 are thus attenuated in the muffler
16.
[0039] The muffler 16 may constitute a front muffler, a central
muffler or a rear muffler of the exhaust system 14.
[0040] In other words, the muffler 16 can be arranged in any place
in the exhaust system 14 and does not have to be directly connected
to the tailpipe 17, as shown schematically in FIG. 1.
[0041] The muffler 16 represented in FIGS. 2 to 4 has a gas-tight
outer housing 18 which is formed by an envelope 20 and two closure
plates 22 arranged at the end side. The muffler 16 is coupled to an
exhaust pipe of the exhaust system 14 via openings in the closure
plates 22.
[0042] The outer housing 18 of the muffler 16 may also be formed,
for example, by two half-shells, a winding envelope or a tube,
instead of being formed by the envelope 20 and the closure plates
22.
[0043] A partition wall 24 is arranged within the outer housing 18
and divides the interior of the outer housing 18 into two chambers
26, 28, more specifically into a Helmholtz chamber 26 and a further
muffler chamber 28.
[0044] Therefore, the partition wall 24 is directly adjacent to the
inner envelope surface 30 of the outer housing 18.
[0045] In the embodiment of FIG. 2, the Helmholtz chamber 26 is
delimited by a section of an inner envelope surface 30 of the outer
housing 18, the partition wall 24, and one of the closure plates
22.
[0046] Furthermore, the muffler 16 has two exhaust pipes 32 which
extend in the longitudinal direction L of the muffler 16 and
through the outer housing 18.
[0047] In other words, the exhaust pipes 32 are thus arranged at
least in sections within the outer housing 18.
[0048] The exhaust pipes 32 are laterally spaced apart from each
other, i.e. they are separated by a distance "d" transversely to
the direction of extension of the exhaust pipes 32.
[0049] In the embodiment of FIG. 2, the exhaust pipes 32 are formed
parallel to each other within the outer housing 18, i.e. the
direction of extension of the exhaust pipes 32 within the outer
housing 18 is parallel, and the exhaust pipes 32 extend linearly
through the outer housing 18.
[0050] Generally, it is also conceivable that the exhaust pipes 32
extend in a curved manner through the outer housing 18.
[0051] The exhaust pipes 32 form a flow path for an exhaust gas.
Each exhaust pipe 32 respectively includes two exhaust pipe
sections 34 which are entirely spaced apart from each other in the
flow direction of the exhaust gas (represented by arrows 33).
[0052] In other words, a laterally entirely circumferential gap 36
is respectively provided between the exhaust pipe sections 34 in
the respective flow path through the exhaust pipes 32.
[0053] In addition to the outer housing 18 and the exhaust pipes
32, the muffler 16 has a feed body 38 which is formed by two
half-shells 39 (FIG. 3).
[0054] The feed body 38 is thus a two-piece element, the
respectively one-piece half-shells 39 being placed onto the exhaust
pipes 32 from two opposite sides of the exhaust pipes 32, being
firmly connected to each other and being connected to the exhaust
pipes 32.
[0055] The half-shells 39 are in particular connected to each other
by an intermaterial bond and are also connected to the exhaust pipe
sections 34 by an intermaterial bond, by soldering or welding, for
example.
[0056] In the design of FIG. 2, the half-shells 39, i.e. the feed
body 38, are connected to each exhaust pipe section 34 by an
intermaterial bond.
[0057] In the region of the gaps 36, the feed body 38 has two
annular sections 40. The annular sections 40 enclose the exhaust
pipes 32 over the entire circumference in the region of the gaps
36, seals them with respect to the environment and form a flow path
for the exhaust gas via the gaps 36 into the space between the
exhaust pipes 32.
[0058] A feed section 42 in the shape of tab-like, plate-like
projections of the feed body 38 extends from the downstream end of
the annular sections 40. As the feed sections 42 are attached to
the exhaust pipes 32, a channel 43 is produced which forms the neck
of a Helmholtz resonator 41 (cf. FIG. 3). The feed section 42 opens
via an opening 44 into the Helmholtz chamber 26.
[0059] The feed section 42 also has an opening 44 (FIG. 4) via
which the exhaust pipes 32 are fluidically connected to the
Helmholtz chamber 26.
[0060] The feed body 38 and the Helmholtz chamber 26 thus form a
Helmholtz resonator 41 which attenuates specific frequencies
occurring in the exhaust gas in a manner known per se.
[0061] The length I (FIG. 2) of the feed section 42, the distance e
(FIG. 4) of the half-shells 39 to each other in the region of the
opening 44, and/or the distance d between the exhaust pipes 32 is,
for example, adapted to the resonance frequency to be
attenuated.
[0062] In other words, the cross-section and the volume of the feed
body 38 are thus adapted to the resonance frequency in the region
of the feed section 42.
[0063] The Helmholtz chamber 26 is of course also adapted to the
resonance frequency.
[0064] The Helmholtz chamber 26 is fluidically connected to both
exhaust pipes 32 (via the feed body 38). The muffler 16 therefore
provides a Helmholtz resonator 41 for two exhaust pipes 32. In this
way, the structure of a muffler 16 having two exhaust pipes 32 is
simplified. It is in particular not necessary to arrange holes on
the exhaust pipe sections 34; rather, the gap 36 is simply formed
by a spaced apart arrangement of the exhaust pipe sections 34 with
respect to each other.
[0065] Mechanically, the exhaust pipe sections 34 are firmly
connected to each other by the feed body.
[0066] Although various embodiments have been disclosed, a worker
of ordinary skill in this art would recognize that certain
modifications would come within the scope of this disclosure. For
that reason, the following claims should be studied to determine
the true scope and content of this disclosure.
* * * * *