U.S. patent application number 12/660874 was filed with the patent office on 2011-09-08 for removable exhaust baffle.
Invention is credited to Charles Bingham.
Application Number | 20110214937 12/660874 |
Document ID | / |
Family ID | 44455329 |
Filed Date | 2011-09-08 |
United States Patent
Application |
20110214937 |
Kind Code |
A1 |
Bingham; Charles |
September 8, 2011 |
REMOVABLE EXHAUST BAFFLE
Abstract
A selectively removable exhaust baffle which can be placed
within an exhaust pipe to muffle the emitted sound. The removable
baffle preferably includes a frame having a pair of legs joined by
a spring portion. One or more transverse occluding plates are
mounted on the frame. The frame is sized so that when it is pushed
into the exhaust pipe it must be compressed. This compression holds
the frame in place. The transverse occluding plate or plates lie
against the interior wall of the exhaust pipe. The gas flow must
therefore pass around the plate or plates, thereby attenuating the
sound.
Inventors: |
Bingham; Charles;
(Lighthouse Point, FL) |
Family ID: |
44455329 |
Appl. No.: |
12/660874 |
Filed: |
March 5, 2010 |
Current U.S.
Class: |
181/241 |
Current CPC
Class: |
F01N 2240/20 20130101;
F01N 1/083 20130101; F01N 13/1805 20130101; F01N 13/00
20130101 |
Class at
Publication: |
181/241 |
International
Class: |
F01N 13/18 20100101
F01N013/18 |
Claims
1. A method for selectively attenuating the sound produced by an
exhaust pipe having an internal diameter and a central pipe axis,
comprising: a. providing a removable baffle including, i. a first
leg, ii. a second leg, iii. a spring portion connecting said first
and second legs, said spring portion being configured to urge said
second leg pivotally away from said first leg to form a V-spring
having a pivot axis, iv. an occlusion plate, attached to said first
leg, said occlusion plate including a circular portion sized to fit
against said internal diameter of said exhaust pipe, and v. said
V-spring being sized such that said second leg must be compressed
toward said first leg in order to slide said removable baffle into
said internal diameter; b. orienting said removable baffle so that
said pivot axis is perpendicular to said central pipe axis; c.
compressing said second leg toward said first leg while sliding
said removable baffle into said internal diameter; and d. sliding
said removable baffle sufficiently far into said exhaust pipe so
that said occlusion plate lies within said exhaust pipe and impedes
the flow of gas through said exhaust pipe.
2. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 1, further comprising: a.
providing a second occlusion plate on said removable baffle, said
second occlusion plate including a circular portion sized to fit
against said internal diameter of said exhaust pipe, said second
occlusion plate being attached to said second leg; and b. sliding
said removable baffle sufficiently far into said exhaust pipe so
that said first and second occlusion plates both lie within said
exhaust pipe and both occlusion plates impede the flow of gas
through said exhaust pipe.
3. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 2, further comprising: a.
providing a third occlusion plate on said removable baffle, said
third occlusion plate including a circular portion sized to fit
against said internal diameter of said exhaust pipe, said third
occlusion plate being attached to said first leg; and b. sliding
said removable baffle sufficiently far into said exhaust pipe so
that said first, second, and third occlusion plates all lie within
said exhaust pipe and impede the flow of gas through said exhaust
pipe.
4. (canceled)
5. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 1, further comprising providing
said removable baffle with a handle which protrudes beyond said
exhaust pipe when said removable baffle is installed in said
exhaust pipe.
6. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 1, further comprising: a.
providing a mechanical interlocking feature between said exhaust
pipe and said removable baffle, wherein said mechanical
interlocking feature fixes said removable baffle in position so
that it cannot slide further into or out of said exhaust pipe; and
b. engaging said mechanical interlocking feature to secure said
removable baffle in position within said exhaust pipe.
7. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 6, wherein said mechanical
interlocking feature comprises a protrusion on said removable
baffle positioned to snap into a transverse hole in said exhaust
pipe.
8. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 1, further comprising providing an
occlusion plate which is removable so that said occlusion plate may
be disassembled from said first and second legs.
9. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 2, further comprising providing a
first and second occlusion plates which are removable so that said
occlusion plates may be disassembled from said first and second
legs.
10. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 3, further comprising providing a
first, second, and third occlusion plates which are removable so
that said occlusion plates may be disassembled from said first and
second legs.
11. A method for selectively attenuating the sound produced by an
exhaust pipe having an internal diameter and a central pipe axis,
comprising: a. providing a removable baffle including, i. a first
occlusion plate attached to a first leg, ii. a second occlusion
plate attached to a second leg, iii. a spring connecting said first
and second legs, said spring being configured to urge said first
and second legs pivotally away from each other to form a V-spring
having a pivot axis, and iv. said removable baffle being sized such
that said V-spring must be compressed in order to slide said first
and second occlusion plates into said internal diameter; b.
orienting said removable baffle so that said pivot axis is
perpendicular to said central pipe axis; c. compressing said second
occlusion plate toward said first occlusion plate while sliding
said removable baffle into said internal diameter; and d. sliding
said removable baffle sufficiently far into said exhaust pipe so
that said first and second occlusion plates lie within said exhaust
pipe and impede the flow of gas through said exhaust pipe.
12. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 11, further comprising: a.
providing a third occlusion plate on said removable baffle; and b.
sliding said removable baffle sufficiently far into said exhaust
pipe so that said first, second, and third occlusion plates all lie
within said exhaust pipe and impede the flow of gas through said
exhaust pipe.
13. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 11, further comprising providing
said removable baffle with a handle which protrudes beyond said
exhaust pipe when said removable baffle is installed in said
exhaust pipe.
14. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 11, further comprising: a.
providing a mechanical interlocking feature between said exhaust
pipe and said removable baffle, wherein said mechanical
interlocking feature fixes said removable baffle in position so
that it cannot slide further into or out of said exhaust pipe; and
b. engaging said mechanical interlocking feature to secure said
removable baffle in position within said exhaust pipe.
15. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 14, wherein said mechanical
interlocking feature comprises a protrusion on said removable
baffle positioned to snap into a transverse hole in said exhaust
pipe.
16. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 11, further comprising providing
occlusion plates which are removable so that said occlusion plates
may be disassembled from said removable baffle.
17. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 12, further comprising providing
occlusion plates which are removable so that said occlusion plates
may be disassembled from said removable baffle.
18. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 12, further comprising: a.
providing a mechanical interlocking feature between said exhaust
pipe and said removable baffle, wherein said mechanical
interlocking feature fixes said removable baffle in position so
that it cannot slide further into or out of said exhaust pipe; and
b. engaging said mechanical interlocking feature to secure said
removable baffle in position within said exhaust pipe.
19. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 13, further comprising: a.
providing a mechanical interlocking feature between said exhaust
pipe and said removable baffle, wherein said mechanical
interlocking feature fixes said removable baffle in position so
that it cannot slide further into or out of said exhaust pipe; and
b. engaging said mechanical interlocking feature to secure said
removable baffle in position within said exhaust pipe.
20. A method for selectively attenuating the sound produced by an
exhaust pipe as recited in claim 5, further comprising: a.
providing a mechanical interlocking feature between said exhaust
pipe and said removable baffle, wherein said mechanical
interlocking feature fixes said removable baffle in position so
that it cannot slide further into or out of said exhaust pipe; and
b. engaging said mechanical interlocking feature to secure said
removable baffle in position within said exhaust pipe.
21. A method for selectively attenuating the sound produced by an
exhaust pipe as recited claim 11 further comprising providing said
occlusion plates which are selectively removable from said legs.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] Not Applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable.
MICROFICHE APPENDIX
[0003] Not Applicable
BACKGROUND OF THE INVENTION
[0004] 1. Field of the Invention
[0005] The present invention relates generally to sound
attenuation. More specifically, the present invention comprises an
exhaust baffle which may be selectively placed in an exhaust pipe
to reduce emitted exhaust sounds when desired.
[0006] 2. Description of the Related Art
[0007] The present invention is particularly suited for use in
motorcycle exhausts, and the embodiments disclosed in detail will
use motorcycle exhausts as the example. However, the reader should
bear in mind that the invention is by no means limited to this
application and may be more broadly applied to any scenario in
which noise reduction or an increase in back flow pressure is
desired.
[0008] Motorcycles traditionally have fairly simple exhaust
systems. This is particularly true for "V-Twin" engines such as
those produced by HARLEY-DAVIDSON. Such exhausts typically provide
fairly low sound attenuation. The result is a loud and "thunderous"
exhaust tone that many motorcycle enthusiasts find desirable. The
loud exhaust noise is in fact a signature effect of this type of
motorcycle.
[0009] Unfortunately for those desiring the traditional exhaust
sound effects, many municipalities have passed noise ordinances
defining a maximum sound level permitted for operation of a moving
vehicle. Many motorcycles exceed this sound level and may therefore
not be legally operated within the particular municipality. The
ordinances are not uniform, however. Thus, a motorcycle may be
legally operated in many areas yet prohibited from a few areas
which have enacted more strict noise ordinances.
[0010] One solution is of course to add a muffling device to reduce
the exhaust noise so that it complies with the most restrictive
noise ordinance. This would require significant sound attenuation.
Most motorcycle owners would prefer to have the loud sound
available wherever it is legal, and apply the reduced sound only
when required. One can of course change exhaust systems, but this
is cumbersome. One can also equip the exhaust with complex dual
pathways selected by a butterfly valve (as is done in some
automotive applications). Such mechanisms add to the weight and
complexity of a motorcycle, and additionally tend to spoil the
"clean" appearance most motorcycle enthusiasts desire. Thus, it
would be preferable to provide a noise attenuating device which
could be selectively added to an existing exhaust system without
requiring significant modifications. The present invention proposes
just such a design.
BRIEF SUMMARY OF THE INVENTION
[0011] The present invention comprises a selectively removable
exhaust baffle which can be placed within an exhaust pipe to muffle
the emitted sound. The removable baffle preferably includes a frame
having a pair of legs joined by a spring portion. One or more
transverse occluding plates are mounted on the frame. The frame is
sized so that when it is pushed into the exhaust pipe it must be
compressed. This compression holds the frame in place. The
transverse occluding plate or plates lie against the interior wall
of the exhaust pipe in an orientation which is preferably
perpendicular to the direction of gas flow through the exhaust
pipe. The gas flow must therefore pass around the plate or plates,
thereby attenuating the sound.
[0012] A handle is preferably provided. This extends out the rear
of the exhaust pipe to facilitate removal of the baffle. A locking
feature is preferably also provided to securely hold the baffle in
position until removal is desired. The baffle may be constructed in
a variety of ways, with the preferred embodiment being formed by
assembling several pieces which may be stored flat when not in
use.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0013] FIG. 1 is a perspective view, showing a preferred embodiment
of the removable baffle in an assembled state.
[0014] FIG. 2 is a perspective view, showing the removable baffle
being inserted into an exhaust pipe.
[0015] FIG. 3 is a sectional elevation view, showing the removable
baffle in position within an exhaust pipe.
[0016] FIG. 4 is an exploded perspective view, showing a preferred
embodiment in which the removable baffle is assembled from flat
pieces.
[0017] FIG. 5 is a perspective view, showing an embodiment in which
a separate spring is used.
REFERENCE NUMERALS IN THE DRAWINGS
TABLE-US-00001 [0018] 10 removable baffle 12 frame 14 spring
portion 16 front occlusion plate 18 middle occlusion plate 20 rear
occlusion plate 22 handle 24 protrusion 26 first leg 28 second leg
30 exhaust pipe 32 opening 34 hole 36 rear receiver 38 middle
receiver 40 front receiver 42 gas flow 44 notch 46 separate first
leg 48 separate second leg 50 spring 52 first joint 54 second joint
60 land
DETAILED DESCRIPTION OF THE INVENTION
[0019] FIG. 1 shows removable baffle 10 in an assembled state.
Frame 12 preferably assumes the shape of a V-spring, having first
leg 26 and second leg 28 joined by spring portion 14. Those skilled
in the art will appreciate that the two legs may be forced toward
each other, with spring portion 14 tending to bias the two legs
apart.
[0020] One or more occlusion plates are provided to impede the flow
of exhaust gases when the removable baffle is placed in an exhaust
pipe. The number and location of the occlusion plate or plates can
be varied to suit a particular application. In the embodiment
shown, front occlusion plate 16 and rear occlusion plate 20 are
attached to first leg 26. Middle occlusion plate 18 is attached to
second leg 28.
[0021] The occlusion plates shown in the embodiment of FIG. 1 are
half-disks, the diameter of which conforms to the inner diameter of
the exhaust pipe. These features allow the circular portion of each
occlusion disk to fit securely against the interior of the exhaust
pipe. Handle 22 is an extension of the first leg. It is intended to
facilitate the removal of the device from an exhaust pipe, as will
be described in more detail subsequently.
[0022] FIG. 2 shows removable baffle in position and ready to be
inserted into a conventional motorcycle exhaust pipe 30. Frame 12
of the removable baffle is preferably sized so that the two legs
must be compressed together in order to slide the device into the
exhaust pipe. The restoring force of spring portion 14 will then
tend to force the two legs outward against the interior of the
exhaust pipe--thereby frictionally engaging the surface and
retaining the device in position.
[0023] Additional features may be optionally added to more securely
retain the removable baffle within the exhaust pipe. A mechanical
interlocking feature can be provided between the removable baffle
and the exhaust pipe. Returning briefly to FIG. 1, an example of
this mechanical interlocking feature is provided. Protrusion 24 is
provided on first leg 26. Turning back to FIG. 2, the reader will
observe the inclusion of a transverse hole 34 in exhaust pipe 30.
When the user slides the removable baffle into the exhaust pipe,
protrusion 24 snaps into hole 34 and secures the removable baffle
in place.
[0024] FIG. 3 is a sectional elevation view showing the removable
baffle in place within an exhaust pipe 30. The reader will note how
protrusion 24 is secured within hole 34. This interlocking feature
impedes the tendency of the flowing exhaust gases to blow the
device out of the exhaust pipe. The embodiment shown uses three
evenly spaced occlusion plates (front occlusion plate 16, middle
occlusion plate 18, and rear occlusion plate 20). These redirect
gas flow 42 through a serpentine path. The effect is substantially
reduced exhaust noise.
[0025] Handle 22 preferably extends beyond the exit plane of the
exhaust pipe to facilitate the removal of the device. In the
orientation shown, the user need only press down on the handle to
disengage the mechanical interlock. He or she may then slide the
removable baffle to the rear and remove it from the tailpipe.
[0026] Those skilled in the art will realize that the occlusion
plates may assume a virtually infinite variety of forms. They are
shown as being perpendicular to the exhaust gas flow but this need
not be the case. They may be placed at any suitable angle to the
exhaust flow. It is also possible to provide one, two, three, four,
five, or more occlusion plates in order to create the desired level
of sound attenuation. In some applications it may also be desirable
to provide perforated occlusion plates. Simple holes may be
provided, or a more complex array of slots or other shapes.
[0027] The inventive device will be effective in some applications
even though over half of the surface area of each plate is opened
by perforations. Many law enforcement agencies test for exhaust
attenuation by simply inserting a pointer into the exhaust pipe and
feeling for the presence of an obstruction. It is therefore
significant that the perforation design used still leave enough
solid material to obstruct the passage of such a pointer.
[0028] FIG. 4 shows an embodiment in which each occlusion plate is
made removable from frame 12. As an example, middle occlusion plate
18 is provided with a notch 44 sized to interlock with middle
receiver 38 and the accompanying land 60. Front occlusion plate 16
is designed to lock into front receiver 40 and rear occlusion plate
20 is designed to lock into rear receiver 36. In this fashion, a
user may select and install one, two, or three occlusion plates
without the need for tools or fasteners. When not in use, the
entire device may be disassembled and stored in a flat state.
[0029] FIG. 5 shows a different embodiment having a fixed number of
occlusion plates. Separate first leg 46 and separate second leg 48
are forged or cast from a suitable metal with the occlusion plates
and other features integrally formed. The two legs are joined by a
separate spring 50, which is connected via first joint 52 and
second joint 54.
[0030] It may be necessary to leave the removable baffle in place
for extended periods, during which all the components will be
bathed in hot exhaust gases. Thus, heat-resistant metals are the
preferred materials--with stainless steel being one good
example.
[0031] The inventive device and method for its installation are
primarily directed toward reducing exhaust noise. However, those
skilled in the art will also know that the device can be used to
modify exhaust back pressure and to otherwise "tune" the exhaust to
produce a desired sound. Thus, the invention should not be viewed
as being limited solely to sound attenuation.
[0032] The foregoing description and drawings comprise illustrative
embodiments of the present invention. Having thus described
exemplary embodiments of the present invention, it should be noted
by those skilled in the art that the within disclosures are
exemplary only, and that various other alternatives, adaptations,
and modifications may be made within the scope of the present
invention. Many modifications and other embodiments of the
invention will come to mind to one skilled in the art to which this
invention pertains having the benefit of the teachings presented in
the foregoing descriptions and the associated drawings. Although
specific terms may be employed herein, they are used in a generic
and descriptive sense only and not for purposes of limitation.
Accordingly, the present invention is not limited to the specific
embodiments illustrated herein, but is limited only by the
following claims.
* * * * *