U.S. patent number 3,590,578 [Application Number 04/857,661] was granted by the patent office on 1971-07-06 for afterburner apparatus for engine exhaust gas.
This patent grant is currently assigned to Honda Giken Kogyo Kabushiki Kaisha. Invention is credited to Akira Ishizuya, Junji Otani, Shizuo Yagi.
United States Patent |
3,590,578 |
Yagi , et al. |
July 6, 1971 |
AFTERBURNER APPARATUS FOR ENGINE EXHAUST GAS
Abstract
The exhaust pipes from the cylinders of an internal combustion
engine lead to an afterburner chamber and thence to a muffler, and
either a separate pipe or one of the exhaust pipes constitutes a
bypass conduit leading from the afterburner chamber to the muffler.
A control valve device regulates the flow through the exhaust
pipes, with the exception of the bypass conduit, whereby the
exhaust gases from the cylinders can flow directly therefrom to the
muffler or can be diverted through the afterburner chamber and
bypass conduit to the muffler. The valve device is closed when the
engine is at low-power output and open when the engine is at
high-power output.
Inventors: |
Yagi; Shizuo (Saitama-ken,
JA), Ishizuya; Akira (Saitama-ken, JA),
Otani; Junji (Saitama-ken, JA) |
Assignee: |
Honda Giken Kogyo Kabushiki
Kaisha (Tokyo, JA)
|
Family
ID: |
26407554 |
Appl.
No.: |
04/857,661 |
Filed: |
September 15, 1969 |
Foreign Application Priority Data
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|
|
|
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Sep 14, 1968 [JA] |
|
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43/66352 |
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Current U.S.
Class: |
60/288;
60/294 |
Current CPC
Class: |
F01N
3/26 (20130101); F01N 13/08 (20130101); F01N
3/00 (20130101); Y02T 10/20 (20130101); Y02T
10/12 (20130101) |
Current International
Class: |
F01N
3/00 (20060101); F01N 7/08 (20060101); F01N
3/26 (20060101); F01n 003/10 () |
Field of
Search: |
;60/29,30
;23/2C,277C |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Hart; Douglas
Claims
What I claim is:
1. An afterburner apparatus for the exhaust gases from respective
cylinders of an internal combustion engine in combination with a
muffler, said apparatus comprising an afterburner chamber, conduit
mean joining said cylinders and said muffler and providing a first
passage for exhaust gases directly from said cylinders to said
muffler and a second passage in parallel with said first passage
and leading through said afterburner chamber to said muffler, said
first passage opening into said afterburner chamber, and valve
means in said first passage between the afterburner chamber and the
muffler for selectively opening and closing said first passage
which also controls flow of exhaust gases from the first passage
into the afterburner chamber and second passage, said conduit means
comprising exhaust pipes extending from respective cylinders
through said chamber, said pipes having apertures which open into
said chamber.
2. Apparatus as claimed in claim 1 wherein said apertures in the
pipes face in alternating directions within the chamber to avoid
mutual interference.
3. Apparatus as claimed in claim 1 wherein said exhaust pipes form
a common junction between said chamber and said muffler and said
valve means comprises a single valve common to all the exhaust
pipes, said second passage including a bypass conduit extending
from said chamber to said muffler.
4. Apparatus as claimed in claim 1 wherein said valve means
comprises a plurality of valves, one in each exhaust pipe, said
second passage including a bypass conduit extending from said
chamber to said muffler.
5. Apparatus as claimed in claim 1 wherein one of said exhaust
pipes is a bypass conduit included in said second passage, the
remaining exhaust pipes collectively defining said first
passage.
6. Apparatus as claimed in claim 5 wherein said valve means
comprises a single valve common to said remaining exhaust
pipes.
7. Apparatus as claimed in claim 5 wherein said valve means
comprises a separate valve in each of said remaining exhaust
pipes.
8. Apparatus as claimed in claim 5 wherein at least one of said
remaining pipes is joined with said bypass conduit at a juncture
between the chamber and said muffler, said valve means comprising a
separate valve in said at least one remaining pipe before the
juncture thereof with said bypass conduit.
Description
BRIEF SUMMARY OF THE INVENTION
There has been hither to known an afterburner apparatus in which
the exhaust gases of an internal combustion engine are admitted
into an afterburner chamber for being burnt again so that its
unburned ingredients are removed therefrom. The afterburner
chamber, in this case, is usually of a sufficient volume such that,
at the time of high-output power of the engine, the chamber does
not become a resistance to the exhaust gas flow and thereby bring
about lowering of the engine output power. With an afterburner
chamber of large volume, however, at the time of engine starting or
engine low-output power, it is difficult to maintain the interior
of the chamber at a high temperature and the desired afterburner
operation is difficult to perform. Additionally, at the time of
engine starting, the engine is supplied with a comparatively large
amount of fuel for insuring starting so that unburned ingredients
are produced in large amounts. Therefore, nonoperation of the
afterburner chamber at this time is especially undesirable.
An object of this invention is to provide afterburner apparatus
free from the above defects, and characterized in that respective
cylinders of an internal combustion engine are in communication
with a muffler through a first passage comprising their respective
exhaust pipes and having valve means interposed therein, and, in
parallel therewith, a second passage comprising a single common
afterburner chamber and a bypass conduit pipe connected to the
chamber. The valve means is connected with a throttle valve of the
engine through a connecting rod so that the valve means is closed
when the throttle valve is open a comparatively small degree, but
is opened when the throttle valve is open a comparatively large
degree. The valve means may be a single valve common to all the
exhaust pipes, but the valve means can also be an associated
plurality of valves, one for each exhaust pipe.
According to a feature of this invention, at least one of the
exhaust pipes can be utilized to serve also as a bypass conduit
pipe connected between the after burner chamber and the muffler,
and thus the apparatus can be simple in construction and small in
size. This can be achieved only in that at least one of the exhaust
pipes is not controlled by the valve means.
BRIEF DESCRIPTION OF THE DRAWING:
FIG. 1 is a diagrammatic illustration partly in section of one
embodiment according to this invention,
FIG. 2 is a detailed sectional view of an afterburner chamber
portion of the embodiment of FIG. 1,
FIG. 3 is a sectional view taken along line III-III in FIG. 2,
FIG. 4 is a diagrammatic illustration showing a modification of the
above embodiment,
FIG. 5 is a diagrammatic illustration of another embodiment
according to this invention, and
FIGS. 6 and 7 are diagrammatic illustrations showing modifications
thereof.
DETAILED DESCRIPTION
Referring first to FIGS. 1 to 3 showing one embodiment of this
invention, numeral 1 denotes an internal combustion engine
comprising several cylinders, for example, four cylinders 2, 3, 4,
5. Respective exhaust pipes 6, 7, 8, 9 extending from cylinders 2,
3, 4, 5 are joined together at one end into a single common conduit
pipe 10 containing a valve 11 and pipe 10 in turn is connected to a
muffler 12, such that elements 6--11 form a first passage A between
the engine 1 and the muffler 12. On the other hand, the exhaust
pipes 6, 7, 8, 9 are provided with respective small apertures 13,
14, 15, 16 in their respective side surfaces near the cylinders and
the apertures open into a single common afterburner chamber 17 of
comparatively small volume. Chamber 17 is connected to the muffler
12 through a bypass conduit pipe 18, thus providing a second
passage B between the engine 1 and the muffler 12 in parallel with
the first passage A. Numeral 19 denotes a small aperture in the
side surface of the base end portion of the bypass conduit pipe 18
for providing communication between the pipe 18 and the chamber
17.
The valve 11 and a throttle valve 20 of the engine 1 are connected
together by a connecting rod 21 so that the valve 11 is closed when
the valve 20 is open a comparatively small degree (engine
low-output power operation) but is opened when the valve 20 is open
a comparatively large degree (engine high-output power operation).
Numeral 22 is a throttle wire.
As clearly shown in FIGS. 2 and 3, the exhaust pipes 6, 7, 8, 9 and
the bypass conduit pipe 18, are arranged within the afterburner
chamber 17 so that the chamber 17 is increased in its mechanical
strength and the small apertures 13, 14, 15, 16 are disposed in two
rows in alternating directions to provide a zigzag relation for
decreasing mutual interference as much as possible. An outer jacket
23 of the chamber 17 is composed of upper and lower half portions
detachably joined together by bolts 24, to facilitate replacement
of an interior heat insulating material 25.
The operation of this embodiment is as follows:
If the valve 11 is opened, the first passage A is open.
Accordingly, the exhaust gases from the engine 1 are led to the
muffler 12 chiefly through the passage A. Therefore, the chamber 17
does not constitute a flow resistance even if the chamber is
constructed to be of a comparatively small volume. If the valve 11
is closed, the first passage A becomes closed, and accordingly, the
exhaust gases from the engine 1 are led to the muffler 12 through
the second passage B, and therefore through the afterburner chamber
17. Thus, unburned ingredients in the exhaust gas are subjected to
a purification treatment in the chamber 17.
Consequently, in the apparatus according to the invention, the
first passage and the second passage can be selectively utilized by
the operation of the valve 11. In the case of operation of a
vehicle such as a motorcar or the like, at the time of engine
high-output power operation, which is comparatively infrequent and
during which the amount of unburned ingredients contained in the
exhaust gas is comparatively low, the first passage is utilized for
discharging the exhaust gases and thus the use of the afterburner
chamber is eliminated. Accordingly, the deficiency that the chamber
functions as a flow resistance to cause the lowering of engine
output power is avoided even if the chamber is of a comparatively
small volume. On the other hand, at the time of engine starting or
engine low-output power where unburned ingredients are included in
large quantities in the exhaust gases, the second passage B, and
thereby the afterburner chamber 17 is utilized. Accordingly, a
predetermined afterburner operation can be positively effected even
afterburner the after chamber is of a comparatively small
volume.
The embodiment of FIGS. 1 to 3 can be modified as shown in FIG. 4.
Namely, in the embodiment in FIGS. 1 to 3, the valve means is is
single valve 11 common to all the exhaust pipes 6, 7, 8, 9 but the
valve means can be constituted as an associated plurality of valves
11a, 11b, 11c, 11d one for each exhaust pipe as shown in FIG. 4. It
will be easily understood that substantially the same operation can
be effected in this embodiment.
According to another modification, the bypass conduit pipe 18 in
the above embodiments can be eliminated and thereby the apparatus
can be simplified and be made more compact. This can be achieved by
the arrangement as shown in FIG. 5. Namely, as seen in FIG. 5, any
one of the exhaust pipes, for example, the pipe 9 on the extreme
right can be selected to serve as a bypass conduit, and the valve
11 controls only the remaining pipes 6, 7, 8.
The operation of the embodiment of FIG. 5 as follows:
If the valve 11 is opened, the exhaust gas from each cylinder 2, 3,
4, 5 is led to the muffler 12 through their respective exhaust
pipes 6, 7, 8, 9 so that the exhaust gas flow is not subjected to a
flow resistance by the presence of the afterburner chamber 17. In
this case the selected pipe 9 which is not controlled by the valve
11 operates similar to the remaining pipes 6, 7, 8. If, however,
the valve 11 is closed, the exhaust gases from cylinders 2, 3, 4
are led into the chamber 17 through respective small apertures 13,
14, 15 to be burned again and then led to muffler 12 through the
pipe 9.
Thus, in this embodiment, at least one pipe selected from all the
exhaust pipes is designed not to be controlled by the valve 11, so
that the selected pipe can act in almost the same manner as the
remaining pipes when the valve 11 is open, whereas the pipe 9 acts
as a bypass pipe connecting the chamber and the muffler when the
valve 11 is closed. Thus, it is not necessary to provide a separate
bypass conduit and the apparatus can be simplified and made
compact.
It will be easily understood that, instead of the single valve 11
in the embodiment of FIG. 5, three associated valves 11a, 11b, 11c
or two associated valves 11a, 11b can be used as shown in FIGS. 6
and 7 respectively.
* * * * *