U.S. patent application number 14/955943 was filed with the patent office on 2016-09-22 for mounting structure of variable valve for dual exhaust system.
This patent application is currently assigned to Hyundai Motor Company. The applicant listed for this patent is Hyundai Motor Company. Invention is credited to Hak-Son HAN.
Application Number | 20160273424 14/955943 |
Document ID | / |
Family ID | 56853061 |
Filed Date | 2016-09-22 |
United States Patent
Application |
20160273424 |
Kind Code |
A1 |
HAN; Hak-Son |
September 22, 2016 |
MOUNTING STRUCTURE OF VARIABLE VALVE FOR DUAL EXHAUST SYSTEM
Abstract
A mounting structure of a variable valve for a dual exhaust
system may include a muffler, at a front end of which is connected
a first inlet pipe, and at a rear end of which is connected a first
outlet pipe, and a Helmholtz Resonator, at the front end of which
is connected a second inlet pipe, and at a rear end of which is
connected a second outlet pipe, in which a variable valve which is
opened and closed by an Electronic Control Unit (ECU) of a car is
disposed on the second outlet pipe connected to the Helmholtz
Resonator.
Inventors: |
HAN; Hak-Son; (Seongnam-si,
KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hyundai Motor Company |
Seoul |
|
KR |
|
|
Assignee: |
Hyundai Motor Company
Seoul
KR
|
Family ID: |
56853061 |
Appl. No.: |
14/955943 |
Filed: |
December 1, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F01N 1/083 20130101;
F01N 1/165 20130101; F01N 2210/04 20130101; F01N 13/007 20130101;
F01N 1/023 20130101; F01N 2490/15 20130101 |
International
Class: |
F01N 1/16 20060101
F01N001/16; F01N 1/08 20060101 F01N001/08; F01N 13/00 20060101
F01N013/00; F01N 1/02 20060101 F01N001/02 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 19, 2015 |
KR |
10-2015-0037918 |
Claims
1. A mounting structure of a variable valve for a dual exhaust
system comprising: a muffler, at a front end of which is connected
a first inlet pipe, and at a rear end of which is connected a first
outlet pipe; and a Helmholtz Resonator, at the front end of which
is connected a second inlet pipe, and at a rear end of which is
connected a second outlet pipe; wherein a variable valve which is
opened and closed by an Electronic Control Unit (ECU) of a car is
disposed on the second outlet pipe connected to the Helmholtz
Resonator.
2. The mounting structure of the variable valve for the dual
exhaust system of claim 1, wherein the Helmholtz Resonator is
constructed to have relatively small size than the muffler so that
the muffler and the Helmholtz Resonator are arranged
asymmetrically.
3. The mounting structure of the variable valve for the dual
exhaust system of claim 1, wherein the Helmholtz Resonator
comprises: a housing, into an inside of which exhaust gas flows and
a rear end of which is opened; a first baffle arranged transversely
in the housing; a second baffle combined transversely to close the
rear end of the housing; and a resonant chamber partitioned by the
first baffle and the second baffle.
4. The mounting structure of the variable valve for the dual
exhaust system of claim 1, wherein, at a time of low load travel of
the car, the second outlet pipe is closed by the variable valve and
the exhaust gas flows in the second inlet pipe and an inside of the
Helmholtz Resonator so that a booming noise of the car is
significantly reduced.
5. The mounting structure of the variable valve for the dual
exhaust system of claim 1, wherein, at a time of high load travel
of the car, the second outlet pipe is opened by the variable valve
and the exhaust gas is discharged to an outside of the car through
the first outlet pipe and the second outlet pipe.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority to Korean Patent
Application No. 10-2015-0037918 filed Mar. 19, 2015, the entire
contents of which is incorporated herein for all purposes by this
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a mounting structure of
variable valve for dual exhaust system. More particularly, the
present invention relates to a mounting structure of variable valve
for dual exhaust system in which a Helmholtz Resonator is formed to
be relatively small compared to a muffler and a variable valve is
mounted at the rear end of the Helmholtz Resonator so that a second
outlet pipe is selectively opened and closed, whereby the reduction
of the booming noise and the maximization of the power performance
can be achieved at the same time and the production cost can be
significantly reduced.
[0004] 2. Description of Related Art
[0005] The noise entered into the inside of the car is caused by a
variety of factors such as engine driving, road surface bending, or
wind flowed into the car during travel, and a variety of devices
are used to reduce the noise.
[0006] In particular, since the exhaust gas combusted in the inside
of the engine of the car is considerably high temperature and the
velocity thereof almost amounts to the speed of sound so that if it
is discharged into the atmosphere as it is, then it is abruptly
expanded and produces the violent sound, a separate muffler is
mounted on the exhaust gas path of the car to lower the temperature
and the pressure of the exhaust gas so as to reduce the exhaust
sound.
[0007] In general, a muffler is formed in the form of barrel of a
predetermined size, and inside thereof are mounted a plurality of
pipes and baffles so that the exhaust sound can be lowered by
inducing the expansion, resonance and the sound absorption of the
exhaust gas at a time of flow of the exhaust gas.
[0008] Meanwhile, this muffler has a problem in that if the exhaust
gas resistance is raised to reduce the exhaust sound, the
resistance applied to the exhaust gas stroke, that is, the back
pressure is raised so that the output of the engine is lowered, and
to the contrary, if the exhaust gas resistance is lowered to
prevent the output loss of the engine, the exhaust sound is
increased.
[0009] To solve such a problem, a muffler installed with a variable
valve is developed and used to raise the back pressure in the low
speed interval in which the exhaust sound becomes a problem and to
lower the back pressure in the middle and high speed intervals in
which the engine output becomes a problem.
[0010] FIG. 1 is a top view showing a conventional mounting
structure of variable valve for dual exhaust system.
[0011] As shown in FIG. 1, the conventional dual exhaust system
comprises a first inlet pipe 1 and a second inlet pipe 1' which are
branched into two pipes so that the exhaust gas discharged from the
engine of the car can be flowed, a first muffler 2 and a second
muffler 2' reducing the exhaust sound by being respectively
connected to the first inlet pipe and the second inlet pipe, and a
first outlet pipe 3 and a first outlet pipe 3' each discharging the
exhaust gas having passed the first muffler and the second muffler
to the outside of the car.
[0012] At this time, a first variable valve 4 and a second variable
valve 4' which are controlled by the Electronic Control Unit (ECU)
of the car are respectively installed on the first outlet pipe 3
and the second outlet pipe 3' so as to differentiate the level of
the exhaust sound and the back pressure according to the travel
condition of the car.
[0013] However, the conventional mounting structure of variable
valve for dual exhaust system has the problem in that, since the
first variable valve 4 and the second variable valve 4' should be
respectively installed on both sides of the first outlet pipe 3 and
the second outlet pipe 3', there is a difficulty in the respect of
production cost.
[0014] In addition, there are problems in that the conventional
first variable valve 4 and the second variable valve 4' are
respectively installed in the space between the first muffler 2 and
the first tail pipe 5 and in the space between the second muffler
2' and the second tail pipe 5' so that the composition of the
package is difficult, and the entire size of the muffler 2, 2' is
reduced to prepare the installation space for the variable valves
4, 4'.
[0015] The information disclosed in this Background of the
Invention section is only for enhancement of understanding of the
general background of the invention and should not be taken as an
acknowledgement or any form of suggestion that this information
forms the prior art already known to a person skilled in the
art.
BRIEF SUMMARY
[0016] Various aspects of the present invention are directed to
providing a mounting structure of variable valve for dual exhaust
system in which one variable valve is installed only at the rear
end of the Helmholtz Resonator unlike the prior art so that the
production cost and the car weight are significantly reduced.
[0017] Furthermore, various aspects of the present invention are
directed to providing a mounting structure of variable valve for
dual exhaust system in which, although only one variable valve is
installed, the booming noise is significantly reduced compared to
the conventional car and the power performance is maximized.
[0018] According to various aspects of the present invention, a
mounting structure of a variable valve for a dual exhaust system
may include a muffler, at a front end of which is connected a first
inlet pipe, and at a rear end of which is connected a first outlet
pipe, and a Helmholtz Resonator, at the front end of which is
connected a second inlet pipe, and at a rear end of which is
connected a second outlet pipe, in which a variable valve which is
opened and closed by an Electronic Control Unit (ECU) of a car may
be disposed on the second outlet pipe connected to the Helmholtz
Resonator.
[0019] The Helmholtz Resonator may be constructed to have
relatively small size than the muffler so that the muffler and the
Helmholtz Resonator are arranged asymmetrically.
[0020] The Helmholtz Resonator may include a housing, into an
inside of which exhaust gas flows and a rear end of which is
opened, a first baffle arranged transversely in the housing, a
second baffle combined transversely to close the rear end of the
housing, and a resonant chamber partitioned by the first baffle and
the second baffle.
[0021] At a time of low load travel of the car, the second outlet
pipe may be closed by the variable valve and the exhaust gas may
flow in the second inlet pipe and an inside of the Helmholtz
Resonator so that a booming noise of the car is significantly
reduced.
[0022] At a time of high load travel of the car, the second outlet
pipe may be opened by the variable valve and the exhaust gas may be
discharged to an outside of the car through the first outlet pipe
and the second outlet pipe.
[0023] It is understood that the term "vehicle" or "vehicular" or
other similar terms as used herein is inclusive of motor vehicles
in general such as passenger automobiles including sports utility
vehicles (SUV), buses, trucks, various commercial vehicles,
watercraft including a variety of boats and ships, aircraft, and
the like, and includes hybrid vehicles, electric vehicles, plug-in
hybrid electric vehicles, hydrogen-powered vehicles and other
alternative fuel vehicles (e.g., fuel derived from resources other
than petroleum). As referred to herein, a hybrid vehicle is a
vehicle that has two or more sources of power, for example, both
gasoline-powered and electric-powered vehicles.
[0024] The methods and apparatuses of the present invention have
other features and advantages which will be apparent from or are
set forth in more detail in the accompanying drawings, which are
incorporated herein, and the following Detailed Description, which
together serve to explain certain principles of the present
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a top view showing a conventional mounting
structure of variable valve for dual exhaust system according to
the related art.
[0026] FIG. 2A and FIG. 2B are top views showing an entire
configuration of an exemplary mounting structure of variable valve
for dual exhaust system according to the present invention.
[0027] FIG. 3 is a perspective view showing the configuration of
the exemplary variable valve according to the present
invention.
[0028] FIG. 4 is a projective top view showing a configuration of
Helmholtz Resonator according to the present invention.
[0029] FIG. 5 shows graphs comparing a result of analysis of
transmission loss varying upon opening/closing of the variable
valve according to the present invention.
[0030] FIG. 6 shows graphs comparing a tail pipe noise varying upon
opening/closing of the variable valve according to the present
invention.
[0031] FIG. 7 shows graphs comparing an exhaust sound of the
exemplary mounting structure of variable valve for dual exhaust
system according to the present invention and an exhaust sound of
the conventional mounting structure of variable valve for dual
exhaust system at the time of slow acceleration of a car.
[0032] FIG. 8 shows graphs comparing an exhaust sound of the
exemplary mounting structure of variable valve for dual exhaust
system according to an the present invention and an exhaust sound
of the conventional mounting structure of variable valve for dual
exhaust system at the time of rapid acceleration of the car.
[0033] FIG. 9 shows graphs comparing pressure of the exemplary
mounting structure of variable valve for dual exhaust system
according to the present invention and back pressure of the
conventional mounting structure of variable valve for dual exhaust
system.
[0034] It should be understood that the appended drawings are not
necessarily to scale, presenting a somewhat simplified
representation of various features illustrative of the basic
principles of the invention. The specific design features of the
present invention as disclosed herein, including, for example,
specific dimensions, orientations, locations, and shapes will be
determined in part by the particular intended application and use
environment.
DETAILED DESCRIPTION
[0035] 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(s) will be described in conjunction with exemplary
embodiments, it will be understood that the present description is
not intended to limit the invention(s) to those exemplary
embodiments. On the contrary, the invention(s) is/are intended to
cover not only the exemplary embodiments, but also various
alternatives, modifications, equivalents and other embodiments,
which may be included within the spirit and scope of the invention
as defined by the appended claims.
[0036] FIG. 2A and FIG. 2B are top views showing the entire
configuration of the mounting structure of variable valve for dual
exhaust system according to various embodiments of the present
invention, FIG. 3 is a perspective view showing the configuration
of the variable valve according to various embodiments of the
present invention, and FIG. 4 is a projective top view showing the
configuration of the Helmholtz Resonator according to various
embodiments of the present invention.
[0037] As shown in FIG. 2A and FIG. 2B, the exhaust gas discharged
from an engine of the car flows into the muffler 10 and the
Helmholtz Resonator 20 through the first inlet pipe 11 and the
second inlet pipe 21 branched into two pipes.
[0038] In various embodiments, the first inlet pipe 11 is arranged
at the left hand of the car and the second inlet pipe 21 is
arranged at the right hand of the car, and in the likewise manner,
the muffler 10 is arranged at the left hand of the car and the
Helmholtz Resonator 20 is arranged at the right of the car,
however, the reverse configuration is also possible.
[0039] The first outlet pipe 12 and the second outlet pipe 22 are
connected to the rear end of the muffler 10 and the Helmholtz
Resonator 20 respectively, and the first outlet pipe 12 and the
second outlet pipe 22 play role of discharging the exhaust gas,
which passed the muffler 10 and the Helmholtz Resonator 20, to the
outside of the car.
[0040] The inside of the muffler 10 is partitioned by a number of
baffles likewise the typical muffler, and in the muffler 10 are
arranged the first inlet pipe 11, the first outlet pipe 12 and the
middle pipe 13 in consideration of the flow of the exhaust gas.
[0041] On the second outlet pipe 22 connected to the Helmholtz
Resonator 20 is installed a variable valve 30 which opens and
closes the second outlet pipe 22 by being controlled by an Electric
Control Unit (ECU) of the car.
[0042] At this time, unlike in the conventional structure of dual
exhaust system the variable valves (4, 4' of FIG. 1) are arranged
at both outlet pipes (3, 3' of FIG. 1), in the structure of dual
exhaust system according to the present invention, the variable
valve 30 is mounted only at the second outlet pipe 22.
[0043] This is possible since, unlike the prior art, in the present
invention, on both sides are not installed identical mufflers (2,
2' of FIG. 1), but on one side is installed the muffler 10 and on
the other side is installed the Helmholtz Resonator 20.
[0044] As shown in FIG. 3, the variable valve 30 comprises a
rotational motor 31 which is actuated by the ECU according to the
travel condition (car speed, load and the like) of the car, and a
valve cover 32 of the form of the circular plate which is rotated
according to the actuation of the rotational motor.
[0045] Specifically, at the time of low load travel of the car (low
speed travel, low acceleration travel, downward slope travel and
the like), the rotational motor 31 is actuated so that the valve
cover 32 coincides with the section of the second outlet pipe 22 so
as to not allow the exhaust gas to pass.
[0046] On the contrary, at the time of high load travel of the car
(high speed travel, rapid acceleration travel, upward slope travel
and the like), the rotational motor 31 is actuated so that the
valve cover 32 is arranged perpendicular to the section of the
second outlet pipe 22 so as to allow the exhaust gas to pass.
[0047] At this time, since the Helmholtz Resonator 20 is
constructed to have relatively small size than the muffler 10 so
that the muffler 10 and the Helmholtz Resonator 20 are arranged
asymmetrically, in the present invention, it is not necessary to
reduce the size of the muffler 10 to install the variable valve
30.
[0048] Thinking in reverse, the muffler 10 according to the present
invention may be formed to be further larger than the conventional
muffler (2, 2' of FIG. 1), and accordingly the designer of the
muffler 10 can design the muffler 10 to realize the optimum noise
characteristics without having limitation of layout.
[0049] As shown in FIG. 4, the Helmholtz Resonator 20 comprises a
housing 23 into inside of which the exhaust gas flows and the rear
end of which is opened, a first baffle 24 arranged transversely in
the housing, a second baffle 25 combined transversely to close the
rear end of the housing, and a resonant chamber 26 partitioned by
the first baffle 24 and the second baffle 25.
[0050] The Helmholtz Resonator was devised by Helmholtz a German
physiologist to separate a single sound from a complex sound and is
widely used in mechanical system to reduce the flow noise in the
duct.
[0051] In general, the resonator includes a cavity of significantly
large volume and a neck, and the narrow band noise is reduced by
making the resonant frequency, which is determined by the
geometrical information of the cavity and the neck, consistent with
the noise frequency of the duct.
[0052] In various embodiments, at the time of low load travel of
the car, the second outlet pipe 22 is closed by the variable valve
30, the resonant chamber 26 plays the role of the cavity, and the
second inlet pipe 21 plays the role of the neck, so that
accordingly the booming noise of the exhaust gas passing through
the inside of the muffler 10 is significantly reduced.
[0053] At the time of high load travel of the car, the second
outlet pipe 22 is opened by the variable valve 30, and the exhaust
gas is discharged to the outside through the first outlet pipe 12
and the second outlet pipe 22, whereby the power performance of the
car is improved.
[0054] That is, the Helmholtz Resonator 20 according to the present
invention plays the role of low frequency resonator at the time of
low load travel of the car, and plays the role of the muffler in
which the flow path is expanded and the back pressure is
significantly reduced at the time of low load travel of the
car.
[0055] At this time, the second outlet pipe 22 is formed in the
linear shape unlike the outlet pipe used in the conventional
typical muffler, so that the exhaust gas can be directly
discharged, thereby having a significant effect in reducing the
back pressure at the time of high load travel.
[0056] FIG. 5 shows graphs comparing the result of analysis of
transmission loss varying upon opening/closing of the variable
valve according to various embodiments of the present invention,
and FIG. 6 shows graphs comparing the tail pipe noise varying upon
opening/closing of the variable valve according to various
embodiments of the present invention.
[0057] In general, the capacity of noise reduction is represented
by the transmission loss curve obtained at the frequency zone, and
to achieve the effective noise reduction, the peak frequency of the
transmission loss curve should be consistent with the noise
frequency.
[0058] As shown in FIG. 5, when comparing the transmission loss
curve at the time of closing the variable valve 30 according to the
present invention with the transmission loss curve at the time of
opening the variable valve 30, it can be seen that the transmission
loss curve at the time of closing the variable valve 30 has peak
value at the low frequency zone.
[0059] That is, it can be seen that if the variable valve 30 is
closed, the Helmholtz Resonator 20 has the effective noise
reduction characteristics in the low frequency zone, and
accordingly the booming noise of the car is reduced.
[0060] This is more obvious from the graphs comparing the tail pipe
noise shown in FIG. 6. As shown in FIG. 6, it can be seen that the
tail pipe noise at the time of closing the variable valve 30 in the
low Revolution Per Minute (RPM) stage is significantly reduced
compared to the tail pipe noise at the time of opening the variable
valve 30, and accordingly the starting booming noise of the car is
significantly reduced.
[0061] FIG. 7 shows graphs comparing the exhaust sound of the
mounting structure of variable valve for dual exhaust system
according to various embodiments of the present invention and the
exhaust sound of the conventional mounting structure of variable
valve for dual exhaust system at the time of slow acceleration of
the car, FIG. 8 shows graphs comparing the exhaust sound of the
mounting structure of variable valve for dual exhaust system
according to various embodiments of the present invention and the
exhaust sound of the conventional mounting structure of variable
valve for dual exhaust system at the time of rapid acceleration of
the car, and FIG. 9 shows graphs comparing the back pressure of the
mounting structure of variable valve for dual exhaust system
according to various embodiments of the present invention and the
back pressure of the conventional mounting structure of variable
valve for dual exhaust system.
[0062] Specifically, FIG. 7 shows the graphs comparing the exhaust
sound in the condition of Accelerator Position Sensor (APS) 30%
when applying the mounting structure of variable valve for dual
exhaust system according to the present invention and the
conventional mounting structure of variable valve for dual exhaust
system to the real car.
[0063] As shown in FIG. 7, it can be seen that, at the time of slow
acceleration of the car, the structure according to the present
invention has the effect that the starting booming noise is reduced
by about 10% in the low RPM zone (about 2000 RPM or below) compared
to the conventional structure, and the acceleration linearity
(shown in dotted line in FIG. 7) is secured so that there is the
effect in favor of the realization of the dynamic sound
quality.
[0064] FIG. 8 shows the graphs comparing the exhaust sound in the
condition of WOP (Wide Open Throttle) when applying the mounting
structure of variable valve for dual exhaust system according to
the present invention and the conventional mounting structure of
variable valve for dual exhaust system to the real car.
[0065] As shown in FIG. 8, at the time of rapid acceleration of the
car, the structure according to the present invention has the
effect that the dynamic exhaust gas sound quality and the power
performance are maximized in the high RPM zone (about 2000 RPM or
above) compared to the conventional structure.
[0066] Furthermore, as shown in FIG. 9, even when reviewing the
back pressure according to the flow rate of the exhaust gas, the
structure according to the present invention has the effect that
the back pressure is significantly reduced compared to the
conventional structure.
[0067] Therefore, regardless of the fact that the present invention
uses one variable valve 30, the present invention has the improved
effect in all respect compared to the structure using two
conventional variable valves (4, 4' in FIG. 1) that the starting
booming noise is reduced in the low RPM zone and the power
performance is improved in the high RPM zone.
[0068] The present invention having the structure described above
has the effect of reducing the production cost and the car weight
by installing one variable valve only on the second outlet pipe 22
connected to the rear end of the Helmholtz Resonator 20 compared to
installing the variable valves on both sides.
[0069] Furthermore, the present invention has the advantage in that
since the Helmholtz Resonator 20 is formed to have relatively small
size than the muffler 10 so that the muffler 10 and the Helmholtz
Resonator 20 are arranged asymmetrically, it is not necessary to
reduce the size of the muffler to install the variable valve.
[0070] In addition, the present invention has the effect that
although the variable valve 30 is installed only on the Helmholtz
Resonator 20, the second inlet pipe 22 and the Helmholtz Resonator
20 play the role of low frequency resonator at the time of low load
travel (at the time of slow acceleration) so that the booming noise
is significantly reduced compared to the prior art.
[0071] Furthermore, the present invention has the effect that the
variable valve installed on the Helmholtz Resonator is opened so
that the sectional area of the outlet pipe is increased at the time
of high load travel (at the time of rapid acceleration), whereby
the power performance of the car and the dynamic exhaust sound
quality are maximized compared to the prior art.
[0072] As a conclusion, in the present invention, there occurs the
effect that the production cost and the car weight are reduced
compared to the prior art and at the same time the exhaust gas
performance and the power performance are improved so that the
marketability of the car is increased.
[0073] 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
were chosen and described in order to explain certain principles of
the invention and their practical application, to thereby enable
others skilled in the art to make and utilize various exemplary
embodiments of the present invention, as well as various
alternatives and modifications thereof. It is intended that the
scope of the invention be defined by the Claims appended hereto and
their equivalents.
* * * * *