U.S. patent application number 12/438843 was filed with the patent office on 2010-01-21 for collecting part structure of exhaust manifold.
This patent application is currently assigned to CALSONIC KANSEI CORPORATION. Invention is credited to Hiroyuki Okamoto.
Application Number | 20100011755 12/438843 |
Document ID | / |
Family ID | 39364409 |
Filed Date | 2010-01-21 |
United States Patent
Application |
20100011755 |
Kind Code |
A1 |
Okamoto; Hiroyuki |
January 21, 2010 |
COLLECTING PART STRUCTURE OF EXHAUST MANIFOLD
Abstract
A collecting part structure of an exhaust manifold, in which
connecting portions of branch pipes 2 to 5 to a head flange 1 are
arranged on a straight line, has a reinforcement member that
includes two flat plates 10 and 11 to collect and fix downstream
side portions f the branch pipes 2 to 5. The flat plates have the
same length as an inner diameter of a collecting part 6, and are
formed at central positions thereof with slits S1 and S2 facing
each other to be joined with each other like a cross shape. The
flat plate 11 with the slit S2 at an exhaust-gas upstream side, of
the two flat plates 10 and 11, is arranged on a line A2 parallel to
a line on which the connecting portions of the branch pipes 2 to 5
to the head flange 1 are arranged.
Inventors: |
Okamoto; Hiroyuki; (Saitama,
JP) |
Correspondence
Address: |
FOLEY AND LARDNER LLP;SUITE 500
3000 K STREET NW
WASHINGTON
DC
20007
US
|
Assignee: |
CALSONIC KANSEI CORPORATION
|
Family ID: |
39364409 |
Appl. No.: |
12/438843 |
Filed: |
November 1, 2007 |
PCT Filed: |
November 1, 2007 |
PCT NO: |
PCT/JP2007/071287 |
371 Date: |
February 25, 2009 |
Current U.S.
Class: |
60/323 ;
60/324 |
Current CPC
Class: |
F01N 13/08 20130101;
F01N 2260/18 20130101; F01N 13/10 20130101; F01N 2470/10 20130101;
F01N 13/1805 20130101 |
Class at
Publication: |
60/323 ;
60/324 |
International
Class: |
F01N 1/00 20060101
F01N001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 6, 2006 |
JP |
2006-300685 |
Claims
1. A collecting part structure of an exhaust manifold including
four branch pipes in which exhaust-gas upstream side end portions
thereof are connected with a head flange on a straight line,
exhaust-gas downstream side end portions thereof being formed to
have a cross section of a quadrant circle; a collecting part that
collects and contains the exhaust-gas downstream side end portions
of the branch pipes to form a circular cross section; and a
reinforcement member that is disposed among the exhaust-gas
downstream side end portions of the branch pipes to fix the
exhaust-gas downstream side end portions to the collecting part,
the reinforcement member having two flat plates with the same
length as an inner diameter of the collecting part, the flat plates
being provided at central positions with slits facing to each other
to be joined like a cross shape, the collecting part structure
characterized in that one flat plate, of the flat plates, that is
formed with a slit at an exhaust-gas upstream side thereof is
arranged parallel with the straight line on which connecting
portions of the exhaust-gas upstream side end portions to the head
flange.
Description
TECHNICAL FIELD
[0001] The present invention relates to a collecting part structure
of an exhaust manifold that is connected with an engine of a motor
vehicle or the likes.
BACKGROUND OF THE INVENTION
[0002] A conventional collecting part structure of an exhaust
manifold is disclosed in Japanese Patent application Laid-Open
Publication No. 2003-83062. The conventional collecting part
structure of the exhaust manifold includes four branch pipes and a
collecting part, where exhaust-gas upstream side end portions of
the branch pipes are connected with a head flange in line thereon,
exhaust-gas downstream side end portions thereof are formed to have
a cross section shaped like a quadrant circle, and the collecting
part collects and contains the exhaust-gas downstream side end
portions assembled to form a circular cross section. A
reinforcement member is provided among the exhaust-gas downstream
side end portions, being fixed thereto. The reinforcement member is
constructed by two flat plates that are coupled like a cross shape
by engaging slits formed on the flat plates, and it is arranged so
that the flat plates intersect in an oblique direction with a line
on which collecting portion of the exhaust-gas upstream side end
portions of the branch pipes are aligned.
DISCLOSURE OF THE INVENTION
Problem(s) to be Solved by the Invention
[0003] The conventional invention, however, needs to increase plate
thicknesses of the flat plates of the collecting part or use
expensive material for the flat plate for the following reason.
Stress concentration could have generated at the exhaust-gas
downstream end portions of the branch pipes and their peripheral
portions, being generated by stress due to thermal expansion of the
branch pipes and thermal stress due to thermal extension of the
head flange in a longitudinal direction thereof. In this case, the
flat plates are bent so that both upstream side end portions of the
flat plates are not only bent in a width direction thereof so as to
approach to each other, but also are twisted to depart from each
other in a reverse direction with respect to a thickness direction
of the plates, respectively. This requires the flat plates that
have a larger plate thickness or are made of expensive material, in
order to ensure sufficient strength thereof.
[0004] The present invention is made to solve the above-described
problem, and its object is to provide a collecting part structure
of an exhaust manifold that can easily increase the strength to
resist stress concentration at exhaust-gas downstream side end
portions and their circumferential portions of branch pipes.
Means for Solving the Problems
[0005] According to a first aspect of the present invention there
is provided a collecting part structure of an exhaust manifold
including four branch pipes, a collecting part and a reinforcement
member. Exhaust-gas upstream side end portions of the four branch
pipes are connected with a head flange on a straight line, while
exhaust-gas downstream side end portions thereof are formed to have
a cross section of a quadrant circle. The collecting part collects
and contains the exhaust-gas downstream side end portions of the
branch pipes to form a circular cross section. The reinforcement
member is disposed among the exhaust-gas downstream side end
portions of the branch pipes to fix the exhaust-gas downstream side
end portions to the collecting part, and the reinforcement member
has two flat plates with the same length as an inner diameter of
the collecting part. The flat plates are provided at central
positions with slits facing to each other to be joined like a cross
shape. One flat plate, of the flat plates, that is formed with a
slit at an exhaust-gas upstream side thereof is arranged parallel
with the straight line on which connecting portions of the
exhaust-gas upstream side end portions to the head flange.
EFFECT OF THE INVENTION
[0006] In the collecting part structure of the exhaust manifold of
the present invention, the reinforcement member is composed of the
two flat plates that have the same length as the inner diameter of
the collecting part, the flat plates being provided at their
central positions with slits facing to each other, the flat plates
being coupled with each other by engaging the slits with each
other. The one plate with the slit at the exhaust-gas upstream side
is arranged parallel with the straight line on which the connecting
portions of the exhaust-gas upstream side end portions to the head
flange. Each of the flat plates is only bent by stress due to
thermal expansion of the branch pipes and thermal stress of the
head flange in a longitudinal direction thereof so that exhaust-gas
upstream side end portions of the flat plates approach to each
other. The flat plates can be prevented from being twisted so that
exhaust-gas upstream side end portions thereof depart from each
other in a reverse direction with respect to plate thickness
directions of the plates. This is advantageous in strength.
Further, the slit of the plate that is arranged parallel to the
straight line is provided at the exhaust-gas upstream side of the
plate, so that defects, such as stress concentration at the slit
and cracks at its periphery, can be avoided. As a result, strength
can be easily increased to resist against the stress concentration
at the exhaust-gas downstream side end portions of the branch pipes
and their peripheral portions.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The objects, features and advantages of the present
invention will become apparent as the description proceeds when
taken in conjunction with the accompanying drawings, in which:
[0008] FIG. 1 is an entire front view showing an exhaust manifold
to which a collecting part structure of an exhaust manifold of an
embodiment according to the present invention is applied;
[0009] FIG. 2 is an entire right side view showing the exhaust
manifold to which the collecting part structure of the exhaust
manifold of the embodiment according to the present invention is
applied;
[0010] FIG. 3 is a cross sectional view taken along a line S3-S3 in
FIG. 1;
[0011] FIG. 4A is an exploded view showing a reinforcement member
that is used in the first embodiment, and FIG. 4B is a perspective
view of the reinforcement member thereof;
[0012] FIG. 5A and FIG. 5B are views illustrating how to assemble
the reinforcement member of the first embodiment;
[0013] FIG. 6A and FIG. 6B are views illustrating how to assemble
branch pipes and the reinforcement member that are used in the
first embodiment; and
[0014] FIG. 7 is a bottom view showing exhaust-gas downstream side
end portions of the exhaust manifold of the embodiment where a
collecting part is removed.
DESCRIPTION OF REFERENCE NUMBERS
[0015] S1, S2 slit [0016] X1, X2 welded portion [0017] 1 head
flange [0018] 1a connecting surface [0019] 2, 3, 4, 5 branch pipe
[0020] 2a, 3a, 4a, 5a exhaust-gas downstream side end portion
[0021] 2b, 3b, 4b, 5b wall portion (that contacts with a
reinforcement member) [0022] 6 collecting part [0023] 6a
exhaust-gas upstream side end portion [0024] 7 catalyst substrate
[0025] 8 catalytic converter [0026] 9 reinforcement member [0027]
10, 11 flat plate [0028] 10a, 11a cut-off portion [0029] 20
assembly jig [0030] 20a cut-off portion
BEST MODE FOR CARRYING OUT THE INVENTION
[0031] Hereinafter, an embodiment according to the present
invention will be described with reference to the accompanying
drawings.
First Embodiment
[0032] Hereinafter, a first embodiment will be described.
[0033] FIG. 1 is an entire front view showing an exhaust manifold
to which a collecting part structure of an exhaust manifold of the
first embodiment according to the present invention, FIG. 2 is a
right side view of the same, FIG. 3 is a cross sectional view taken
along a line S3-S3 in FIG. 1, FIG. 4A is an exploded view showing a
reinforcement member of the first embodiment, and FIG. 4B is a
perspective view showing the same.
[0034] FIG. 5A and FIG. 5B are views illustrating how to assemble
the reinforcement member of the first embodiment, FIG. 6A and FIG.
6B are views illustrating how to assemble branch pipes and the
reinforcement member, and FIG. 7 is a bottom view illustrating
exhaust-gas downstream side end portions of the exhaust manifold of
the first embodiment where a collecting part thereof is
removed.
[0035] As shown in FIG. 1 and FIG. 2, the collecting part structure
of the exhaust manifold of the first embodiment mainly includes a
head flange 1 that is connected with a not-shown engine, four
branch pipes 2 to 5 that are respectively connected with cylinders
of the engine through the head flange 1, a collecting part 6 that
is formed like a circular cylinder, and a catalytic converter 8
that is connected with the collecting part 6 and contains catalyst
substrate 7.
[0036] As shown in FIG. 1 to FIG. 7, connecting portions, of the
four branch pipes 2 to 5, to the head flange 1 are arranged in line
on a straight line Al.
[0037] On the other hand, as shown in FIG. 3, exhaust-gas
downstream side end portions of the branches 2 to 5 are formed to
have a cross section of quadrant circle, and they are contained in
an exhaust-gas upstream side end portion 6a of the collecting part
6 in a state where the exhaust-gas downstream side end portions of
the branches 2 to 5 are collected to form a circular cross
section.
[0038] In addition, the reinforcement member 9 is provided among
the exhaust-gas downstream side end portions of the branches 2 to
5.
[0039] Specifically, as shown in FIG. 4A and FIG. 4B, the
reinforcement member 9 is composed of two flat plates 10 and 11.
Each of which has a length L1 that is approximately equal to an
inner diameter of the collecting part 6, and they are provide at
central positions on opposed sides thereof with slits S1 and S2,
respectively. The flat plates 10 and 11 are joined by engaging the
slits S1 and S2 with each other to form like a cross shape.
[0040] In addition, both end portions of the flat plate 10 is
formed at an exhaust-gas upstream side thereof with cut-out
portions 10a, while one end portion of the flat plate 11 is formed
at an exhaust-gas upstream side thereof with a cut-off portion
11a.
[0041] In a case where the flat plates 10 and 11 are fixed with
each other, the flat plate 10 is engaged with an assembly jig 20,
and then the flat plate 11 is engaged with the assembly jig 20. In
this assembly, the flat plates 10 and 11 are prevented from being
assembled in a wrong state thereof, because three cut-off portions
20a that are formed on the assembly jig 20 correspond to the
cut-off portions 10a and 11a of the flat plates 10 and 11.
Incidentally, the flat plates 10 and 11 may be fixed with each
other by welding.
[0042] In addition, as shown in FIG. 6, wall portions 2b to 5b of
the branch pipes 2 to 5 and the reinforcement member 9 are fixed
with each other at welded portions X1, as shown in FIG. 3, in a
state where the reinforcement member 9 is disposed among the
exhaust-gas downstream side end portions 2a to 5a and it slightly
projects toward a collecting part 6 side.
[0043] In this state, the flat plate 11, which is formed with the
slit S2 at the exhaust-gad upstream side thereof, is set parallel
to a line A1, namely on a line A2 that is parallel to the line A1,
on which connecting portions of the branch pipes 2 to 5 that are
connected with the head flange 1 are aligned on a connecting
surface 1 a of the head flange 1.
[0044] Further, as shown in FIG. 3, the branch pipes 2 to 5 are
inserted into the exhaust-gas upstream side end portion 6a together
with the reinforcement member 9, and then outer circumferential
surfaces of the branches 2 to 5 are fixed to the collecting part 6
together with a part of the reinforcement member 9 at welded
portions X2.
[0045] In the thus-constructed collecting part structure of the
exhaust manifold, exhaust gas flows in the collecting part 6 from
the cylinders of the engine through the branch pipes 2 to 5, and
then it is discharged into the catalytic converter 8.
[0046] In this operation, the head flange 1 thermally expands
mainly in a longitudinal direction thereof due to heat of the
exhaust gas, since the connecting portions of the branch pipes 2 to
5 are arranged on the straight line L1. As a result, its thermal
stress acts on the branch pipes 2 to 5 in a direction where the
exhaust-gas downstream side end portions 2a to 5a of the branch
pipes 2 to 5 are separated from each other outwardly in a
longitudinal direction thereof.
[0047] Accordingly, since the flat plate 11, the slit S2 of which
is provided at the exhaust-gas upstream side, is aligned on the
line A2 that is parallel to the line A1 on which the connecting
portions of the branch pipes 2 to 5 on the connecting surface 1a of
the head flange 1 are arranged, the thermal stress acts on the flat
plate 11 only in a direction where the flat plate 11 is bent in
directions indicated by arrows B1 and B2, without stress acting
thereon so that the upstream side both end portions of the flat
plate 11 are twisted in reverse directions. Therefore, the plate 11
is advantageous in strength. In addition, when these bending forces
acts, it becomes easy to avoid the stress that is concentrated at
the slit S2 to tear the flat plate 11 at the slit S2, because the
slit S2 is formed at the exhaust-gas upstream side of the flat
plate 11 and there is no slit at the exhaust-gas downstream side
thereof. Further, there is no twisting stress that twists the
exhaust-gas upstream side end portions of the flat plate 10, which
is arranged in perpendicular to the flat plate 11. Additionally,
the bending stress acts in the directions indicated by B1 and B2,
and accordingly it approximately does not act on the slit S1. This
is advantageous in strength to the flat plate 10. Thus, there is no
danger in compression buckling of the flat plate 10 due to the
thermal stress, and strength can be improved at peripheral portions
of the exhaust-gas downstream side end portions 2a to 5a of the
branch pipes 2 to 5.
[0048] As described above, in the collecting part structure of the
exhaust manifold of the first embodiment, the exhaust manifold
includes the four branch pipes 2 to 5, the collecting part 6 and
the reinforcement member 9. Exhaust-gas upstream side end portions
of the four branch pipes 2 to 5 are connected with the head flange
1 on the straight line, while exhaust-gas downstream side end
portions thereof are formed to have the cross section of the
quadrant circle. The collecting part 6 collects and contains the
exhaust-gas downstream side end portions 2a to 5a of the branch
pipes to form the circular cross section. The reinforcement member
9 is disposed among the exhaust-gas downstream side end portions 2a
to 5a of the branch pipes 2 to 5 to fix the exhaust-gas downstream
side end portions to the collecting part 6, and the reinforcement
member 9 has the two flat plates 10 and 11 with the same length L1
as an inner diameter of the collecting part 6. The flat plates 10
and 11 are provided at the central positions with slits S1 and S2
facing to each other to be joined like the cross shape. The one
flat plate 11, of the flat plates 10 and 11, that is formed with
the slit S2 at an exhaust-gas upstream side thereof is arranged
parallel with the straight line A1 on which the connecting portions
of the exhaust-gas upstream side end portions to the head flange 1.
Therefore, the exhaust-gas upstream side both end portions of the
flat plates 10 and 11 can be prevented from being twisted in the
reverse direction, which is advantageous in strength. As a result,
the strength can be easily increased to resist the stress
concentration at the exhaust-gas downstream side end portions 2a to
5a and their peripheral portions.
[0049] While the embodiment has been explained above, the present
invention is not limited to the above-described embodiment, and its
design changes and modifications are contained in the present
invention as long as they do not depart from the subject-matter of
the present invention.
[0050] For example, as explained above, the flat plate 11 that is
formed with the slit S2 at the exhaust-gas upstream side is
arranged parallel to the connecting surface 1a of the head flange 1
in the first embodiment, while it is preferable that an exhaust-gas
upstream side slit be formed on one of the flat plates 10 and 11
which is arranged in a state where the one is closer to parallel to
the connecting surface la of the head flange 1. This case can also
obtain the effects of the present invention.
* * * * *