U.S. patent application number 12/812375 was filed with the patent office on 2011-01-13 for exhaust silencer.
Invention is credited to Leif Larson.
Application Number | 20110005856 12/812375 |
Document ID | / |
Family ID | 43431222 |
Filed Date | 2011-01-13 |
United States Patent
Application |
20110005856 |
Kind Code |
A1 |
Larson; Leif |
January 13, 2011 |
EXHAUST SILENCER
Abstract
An exhaust silencer of a combustion engine, comprising a housing
(1) that is to be connected to an exhaust pipe, through which
housing the exhaust gases are arranged to be conducted and which
comprises a reactive part (2) and an absorbing part (3) in the flow
direction of the exhaust gases. The reactive part (2) is mainly
hollow and comprises, at the inlet thereof, a first exhaust pipe
(5) for feeding the exhaust gases to the reactive part (2) and, at
its outlet, a second exhaust pipe (6) for directing the exhaust
gases from the reactive part (2) to the absorbing part (3), both
exhaust pipes (5, 6) being arranged so as to essentially extend
inside the reactive part (2) of the housing. The absorbing part (3)
comprises an absorbing filling element (7), which essentially fills
the absorbing part (3) of the housing and, at the inlet of the
absorbing part (3), is shaped so as to direct the exhaust gases to
the space (8) between the filling element (7) and the inner lining
of the housing (1).
Inventors: |
Larson; Leif; (Vaasa,
FI) |
Correspondence
Address: |
Muncy, Geissler, Olds & Lowe, PLLC
4000 Legato Road, Suite 310
FAIRFAX
VA
22033
US
|
Family ID: |
43431222 |
Appl. No.: |
12/812375 |
Filed: |
January 2, 2009 |
PCT Filed: |
January 2, 2009 |
PCT NO: |
PCT/FI2009/050003 |
371 Date: |
September 10, 2010 |
Current U.S.
Class: |
181/211 ;
181/252 |
Current CPC
Class: |
F01N 1/04 20130101; F01N
1/085 20130101; F01N 1/089 20130101; F01N 1/10 20130101 |
Class at
Publication: |
181/211 ;
181/252 |
International
Class: |
F01N 1/10 20060101
F01N001/10; F01N 3/021 20060101 F01N003/021 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 9, 2008 |
FR |
20085013 |
Claims
1. An exhaust silencer of a combustion engine, comprising a housing
that is to be connected to an exhaust pipe, through which housing
the exhaust gases are arranged to be conducted, the housing
comprising a reactive part and an absorbing part in the flow
direction of the exhaust gases, whereby the reactive part is mainly
hollow and comprises, at the inlet thereof, a first exhaust pipe
for feeding the exhaust gases to the reactive part and, at its
outlet, a second exhaust pipe for directing the exhaust gases from
the reactive part to the absorbing part, both the exhaust pipes
being arranged to essentially extend inside the reactive part of
the housing, wherein the absorbing part comprises an absorbing
filling element, which essentially fills the absorbing part of the
housing and, at the inlet of the absorbing part, is shaped so as to
direct the exhaust gases from the central part of the housing to
the space between the filling element and the inner lining of the
housing.
2. The silencer according to claim 1, wherein the first and second
exhaust pipes are dimensioned so as to suppress the lowest
frequencies of the exhaust noise by utilizing the mutual
suppression interference of sonic waves.
3. The silencer according to claim 1, wherein the mouths of first
and second exhaust pipes, which are situated opposite each other,
are arranged at a distance from each other.
4. The silencer according to claim 1, wherein the first exhaust
pipe extends inside the reactive part for about a fourth of the
total length of the reactive part.
5. The silencer according to claim 1, wherein the second exhaust
pipe extends inside the reactive part for about a half of the total
length of the reactive part.
6. The silencer according to any of the preceding claims, wherein
between the reactive part and the absorbing part, there are spark
quenching means.
7. The silencer according to claim 6, wherein the spark quenching
means comprise a number of radially extending plate elements, which
are shaped so as to direct the exhaust gas flow into a rotating
movement around the filling element of the absorbing part.
8. The silencer according to claim 6, wherein the housing
comprises, in connection with the absorbing part and after the
spark quenching means, a soot trap door in the longitudinal
direction of the housing for recovering the soot particles and, if
required, removing them from the housing.
9. The silencer according to claim 1, wherein the filling element,
on the side of the reactive part, is sharp-pointed.
10. The silencer according to claim 1, wherein the filling element
mainly consists of mineral wool, which is arranged inside a
perforated plate, net or the like, which is supported on the
housing.
11. The silencer according to claim 1, wherein, in an operating
situation, the housing is situated in the vertical direction, so
that the exhaust gases are fed to the housing from below.
12. The silencer according to claim 9, wherein the filling element,
on the side of the reactive part, is conical.
Description
[0001] The invention relates to an exhaust silencer according to
the preamble of claim 1, comprising a housing that is to be
connected to an exhaust pipe, exhaust gases being arranged to be
conveyed through the housing that comprises a reactive part and an
absorbing part in the flow direction of the exhaust gases.
[0002] Large combustion engines cause noises, one considerable
source of which comprises the exhaust noise of the engine, which is
mainly caused by pressure variations between the cylinders of the
engine and outdoor air. Various silencers that are connected to the
exhaust manifold or the exhaust pipe are already known. The problem
is how to connect effective enough noise suppression with a
relatively simple and cost-effective structure that would not cause
an excessively high counterpressure in the exhaust system.
[0003] The purpose of the invention is to provide an improved
solution to the above-mentioned problem that is related to the
noise suppression of the exhaust gases of large combustion engines,
in particular. In particular, the purpose of the invention is to
provide an exhaust silencer, which eliminates various frequencies
of acoustic noise in a structurally advantageous manner and as
effectively as possible. A further purpose of the invention is to
provide a silencer that is also capable of purifying the exhaust
gases.
[0004] The objectives of the invention are mainly achieved in the
manner that is described in detail in claim 1 and the other claims.
According to the invention, the reactive part of the silencer is
mainly hollow and comprises, at its inlet, a first exhaust pipe for
feeding the exhaust gases to the reactive part and, at its outlet,
a second exhaust pipe for conducting the exhaust gases from the
reactive part to the absorbing part, both exhaust pipes being
arranged to essentially extend inside the reactive part of the
housing. The absorbing part comprises an absorbing filling element,
which essentially fills the absorbing part of the housing and, at
the inlet of the absorbing part, is formed so as to direct the
exhaust gases to the space between the filling element and the
inner lining of the housing.
[0005] While being as simple as possible, the structure according
to the invention can be used to effectively suppress the low,
medium and high frequencies of the exhaust noise of the engine. The
solution is also advantageous regarding the total counterpressure
caused by the exhaust system.
[0006] The said first and second exhaust pipes are preferably
dimensioned so that they suppress the lowest frequencies of the
exhaust noise by utilizing the mutual suppressive interference of
sonic waves. In that case, the mouths of the said first and second
exhaust pipes that are situated opposite each other are also
arranged at a distance from each other. In practice, the said first
exhaust pipe extends inside the reactive part for about one fourth
of the total length of the reactive part. Correspondingly, the said
second exhaust pipe extends inside the reactive part for about a
half of the total length of the reactive part.
[0007] By arranging spark quenching means between the reactive part
and the absorbing part, the soot particles in the exhaust gases can
effectively be separated before the exhaust gases are released into
the environment. In that case, besides purifying the exhaust gases
as such, the purpose is also to prevent sparks from escaping out of
the exhaust pipe and from possibly causing fire safety risks.
[0008] The spark quenching means preferably comprise a number of
radially extending plate elements, which are formed so as to direct
the exhaust gas flow into a rotating movement around the filling
element of the absorbing part. In this way, the soot particles can
effectively be directed onto the inner lining of the housing under
the effect of centrifugal force. By arranging in the housing, in
connection with the absorbing part and after the spark quenching
means, a soot trap door in the longitudinal direction of the
housing, the soot particles can then be recovered and, where
necessary, easily removed from the housing.
[0009] By directing the exhaust gases towards the inner surface of
the housing, the space between the housing and the filling element
can be rendered relatively small compared to the diameter of the
filling element. In that case, the total cross-sectional area of
the space can be kept large enough, so that the arrangement does
not increase the counterpressure of the exhaust silencer to a
considerable extent. On the whole, the arrangement, for its part,
also improves the suppression of medium and high-frequency
noise.
[0010] To effectively direct the exhaust gases, the filling element
on the side of the reactive part is preferably sharp-pointed, and
most preferably conical.
[0011] The filling element preferably mainly consists of mineral
wool, which is arranged inside a perforated plate, net or the like
that is supported on the housing.
[0012] In an operating situation, the housing is preferably
situated in the vertical direction, so that the exhaust gases are
fed into the housing from below.
[0013] In the following, the invention is described by means of
examples and with reference to the appended schematic drawings, in
which
[0014] FIG. 1 shows an embodiment of the exhaust silencer according
to the invention as a longitudinal section, and
[0015] FIG. 2 shows an axonometric illustration of the silencer of
FIG. 1, with the housing of the silencer cut open and the absorbing
material removed.
[0016] The reference number 1 refers to the housing of the exhaust
silencer, which is attached to the exhaust pipe of a combustion
engine to direct the exhaust gases through the silencer. The
housing 1 comprises a reactive part 2 and an absorbing part 3,
which are arranged sequentially in the flow direction. Between
these, there are the spark quenching means 4.
[0017] The reactive part 2 is intended for suppressing low noises
and it includes a first exhaust pipe 5, through which the exhaust
gases are fed into the housing 1, and a second exhaust pipe 6,
which is arranged at a distance from the first exhaust pipe 5 and
through which the exhaust gases are directed, through the spark
quenching means 4, to the absorbing part 3, wherein the suppression
of medium and high-frequency exhaust noise, in turn, is provided
before the exhaust gases are directed out of the silencer and into
the environment.
[0018] For the absorption of low noises, the first exhaust pipe 5
extends inside the reactive part 2 for about one fourth of the
total length of the reactive part 2. Correspondingly, the second
exhaust pipe 6 extends inside the reactive part 2 for about a half
of the total length of the reactive part 2. In this way, the low
noises can effectively be suppressed by utilizing the mutual
suppression interference of sonic waves. To improve the
effectiveness of the noise suppression, the dimensioning should
also take into consideration the sparking frequency of the
combustion engine and the diameters of the silencer and the exhaust
pipe of the engine, as well as the respective requirements made of
noise suppression.
[0019] The absorbing part 3 contains a filling element 7, which
preferably consists of mineral wool and is surrounded by a
perforated plate material, wire mesh or the like, which is
supported on the housing 1. At its end next to the reactive part 2,
the filling element 7 is rendered conical, so that the exhaust
gases are directed to the space 8 between the inner lining of the
housing 1 and the filling element 7 to be further conducted
outside.
[0020] The spark quenching means 4 include a number of radially
extending plate elements 9, which are shaped so as to direct the
exhaust gas flow into a rotating movement around the filling
element 7 of the absorbing part. The rotating movement thus
provided is tailor-made to direct the soot particles, which are
heavier than the exhaust gases, towards the inner lining of the
housing 1, where they can be easily recovered and removed from the
housing through a longitudinal soot trap door 10.
[0021] The exhaust silencer according to the invention preferably
has a rotationally symmetrical structure, and it can preferably be
situated in the vertical direction, in so far as the application so
requires. In this position, the soot door is also easy to open and
empty.
[0022] The structure of the exhaust silencer according to the
invention is advantageous regarding the total counterpressure
inflicted on the exhaust system. Furthermore, the spark quenching
means can easily be integrated into it, directing, for their part,
the exhaust gases radially outwards towards the inner lining of the
housing.
[0023] The invention is not limited to the above embodiment, but
various modifications can be considered within the appended
claims.
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