U.S. patent application number 12/227977 was filed with the patent office on 2009-11-26 for exhaust apparatus.
This patent application is currently assigned to TOYOTA JIDOSHA KABUSHIKI KAISHA. Invention is credited to Junichi Yamaguchi.
Application Number | 20090288912 12/227977 |
Document ID | / |
Family ID | 38544051 |
Filed Date | 2009-11-26 |
United States Patent
Application |
20090288912 |
Kind Code |
A1 |
Yamaguchi; Junichi |
November 26, 2009 |
Exhaust apparatus
Abstract
In the vicinity of the floor of a vehicle and downstream of the
muffler, a pair of cross members are provided to sandwich the first
portion (i.e. the intermediate portion) of the exhaust pipe from
the top and bottom. The minimum distance in the vertical direction
of the cross members is smaller than the maximum height of the
muffler. By doing this, when the muffler is displaced toward the
rear of the vehicle, the muffler comes into contact with and is
caught by the pair of cross members. The distance in the
longitudinal direction of the vehicle between the part of the cross
members which the muffler catches on and the part of the muffler
which the cross members make contact with is set to be a smaller
value than the minimum distance between the second portion of the
exhaust pipe and the fuel tank.
Inventors: |
Yamaguchi; Junichi;
(Kasugai-shi, JP) |
Correspondence
Address: |
OLIFF & BERRIDGE, PLC
P.O. BOX 320850
ALEXANDRIA
VA
22320-4850
US
|
Assignee: |
TOYOTA JIDOSHA KABUSHIKI
KAISHA
Toyota-shi
JP
|
Family ID: |
38544051 |
Appl. No.: |
12/227977 |
Filed: |
June 1, 2007 |
PCT Filed: |
June 1, 2007 |
PCT NO: |
PCT/IB2007/001443 |
371 Date: |
April 14, 2009 |
Current U.S.
Class: |
181/227 |
Current CPC
Class: |
F01N 13/1822 20130101;
F01N 13/1811 20130101; B60K 13/04 20130101 |
Class at
Publication: |
181/227 |
International
Class: |
F01N 7/08 20060101
F01N007/08 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 7, 2006 |
JP |
2006-158392 |
Claims
1. An exhaust apparatus comprising: a fuel system apparatus,
provided at the rear of a vehicle; an exhaust pipe, connected to an
internal combustion engine mounted aboard the vehicle; and a
muffler, provided midway in the exhaust pipe, wherein the exhaust
pipe has a first portion and a second portion which are disposed
downstream from the muffler; the first portion of the exhaust pipe
connects with the muffler and extends from the muffler to the
second portion of the exhaust pipe; and the second portions of the
exhaust pipe is bent with respect to the first portion of the
exhaust pipe and extends toward the rear of the vehicle, wherein
the second portion of the exhaust pipe maintains a prescribed
clearance around the fuel system apparatus along at least a part of
the fuel system apparatus, the exhaust apparatus further comprises
a restricting member, provided behind the muffler, which makes
contact with the muffler to restrict the displacement of the
muffler when the muffler is displaced toward the rear of the
vehicle, wherein a distance in the longitudinal direction of the
vehicle between the restricting member and the mufflers is smaller
than the minimum distance in the longitudinal direction of the
vehicle between the second portion of the exhaust pipe and the fuel
system apparatus.
2. The exhaust apparatus according to claim 1, wherein the
restricting member is a cross member that reinforces the
vehicle.
3. The exhaust apparatus according to claim 2, wherein a pair of
cross members are provided to sandwich, from above and below, a
rear portion of the mufflers, and the minimum distance between the
pair of cross members is smaller than the maximum height of the
muffler.
4. The exhaust apparatus according to claim 1 wherein a joint that
absorbs vertical displacement of the first portion of the exhaust
pipe associated with the vertical displacement of the muffler is
provided in the first portion of the exhaust pipe.
5. The exhaust apparatus according to claim 1 wherein a part that
bends more easily when the muffler is displaced vertically than
other part of the exhaust pipe is provided in the first portion of
the exhaust pipe.
6. The exhaust apparatus according to claim 1, wherein the fuel
system apparatus is a fuel tank.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an exhaust apparatus that
discharges exhaust gas from an internal combustion engine mounted
aboard a vehicle.
[0003] 2. Description of the Related Art
[0004] A vehicle such as an automobile has a fuel system apparatus
such as a fuel tank provided at rear of the vehicle and an exhaust
apparatus that extends toward the rear of the vehicle to discharge
exhaust from the internal combustion engine of the vehicle to the
rear of the vehicle. Japanese Patent Application Publication No.
JP-A-5-87223 discloses as an exhaust apparatus in which a muffler
is provided midway in an exhaust pipe connected to the internal
combustion engine, a part of the exhaust pipe downstream of the
muffler is bent upward to pass over the top of a fuel tank.
[0005] In the above-noted exhaust apparatus, when the vehicle is
subject to a rear-end collision, the exhaust pipe is pushed forward
from the rear, because there is no displacement at the front part
of the internal combustion engine and at the joining part of the
exhaust pipe with the engine, and because the part of the exhaust
pipe downstream of the muffler is bent upward, that part is bent to
bulge farther upward. For this reason, when the vehicle is
subjected to a rear-end collision, interference between the part of
the exhaust pipe downstream of the muffler and the fuel tank is
avoided.
[0006] As described above, bending the part of the exhaust pipe
downstream of the muffler to pass over the top of the fuel tank
makes it is possible to eliminate interference between this part
with the fuel tank when the vehicle is subjected to a rear-end
collision.
[0007] When a front-end collision occurs, however, because the
internal combustion engine is displaced toward the rear of the
vehicle and, as a result, the overall exhaust apparatus is
displaced toward the rear of the vehicle, the part of the exhaust
pipe downstream of the muffler may interfere with the fuel
tank.
[0008] Although the foregoing problem may be addressed by providing
additional space in the longitudinal direction of the vehicle
between the part downstream of the muffler and the fuel tank, it is
difficult to simultaneously provide the additional space and
maintain sufficient underfloor space.
SUMMARY OF THE INVENTION
[0009] The present invention provides an exhaust apparatus capable
of avoiding interference with the fuel system apparatus when a
front-end collision occurs, and also provides sufficient underfloor
space.
[0010] The means and operating effects of the present invention to
achieve the above-noted object is described below. A first aspect
of an exhaust apparatus in accordance with the invention includes
an exhaust pipe connected to an internal combustion engine mounted
aboard a vehicle and a muffler provided midway in the exhaust pipe,
wherein a first portion of the exhaust pipe and a second portion of
the exhaust pipe are disposed downstream of the muffler; the first
portion of the exhaust pipe is connected to the muffler and extends
from the muffler toward a fuel system apparatus that is disposed at
the rear of the vehicle; and the second portion of the exhaust pipe
is bent with respect to the first portion of the exhaust pipe and
extends toward the rear of the vehicle while maintaining a
prescribed clearance around the fuel system apparatus along at
least a part of the fuel system apparatus. This aspect further has
a restricting member, behind the muffler, which contacts with the
muffler so that it restricts the rearward displacement of the
muffler, wherein a distance in the longitudinal direction of the
vehicle between the contacting parts is smaller than the minimum
distance in the longitudinal direction of the vehicle between the
second portion of the exhaust pipe and the fuel system
apparatus.
[0011] According to the above constitution, when the vehicle is
subjected to a front-end collision, with the displacement of the
internal combustion engine toward the rear of the vehicle, there is
an accompanying displacement of the overall exhaust apparatus
toward the rear of the engine. Before the second portion of the
exhaust pipe interferes with the exhaust apparatus, the muffler
comes into contact with the restricting member, which restricts the
muffler from being displaced toward the rear of the vehicle. For
this reason, the first portion of the exhaust pipe and the second
portion of the exhaust pipe that are connected to the muffler are
not further displaced toward the rear of the vehicle, making it
possible to avoid interference by the second portion of the exhaust
pipe with the fuel system apparatus. Also, as a result of
establishing underfloor space in the vehicle, even in the case in
which it is not possible to establish a sufficient distance between
the second portion of the exhaust pipe and the fuel system
apparatus, by setting a smaller distance in the longitudinal
direction of the vehicle between the muffler and the restricting
member in comparison with the distance between the second portion
of the exhaust pipe part and the fuel system apparatus, it is
possible to achieve the above-noted effect.
[0012] In the above aspect, the restricting member may be a cross
member that reinforces the vehicle. Because the cross member in the
above-noted constitution serves also as a restricting member, it is
not necessary to provide an additional restricting member, which
avoids the additional cost of providing of providing an additional
restricting member.
[0013] A pair of cross members may be provided to sandwich, from
top and bottom, a part of the muffler positioned toward the rear of
the vehicle in the exhaust pipe, and wherein the minimum distance
between the pair of cross members may be set to be smaller than the
maximum height of the muffler.
[0014] According to the above-noted constitution, when the vehicle
is subjected to a front-end collision and there is an accompanying
displacement of the overall exhaust apparatus toward the rear of
the vehicle, the cross members restrict the muffler from further
displacement toward the rear of the vehicle. For this reason, it is
possible to properly restrict the first portion of the exhaust pipe
and the second portion of the exhaust pipe connected to the muffler
from further displacement toward the rear of the vehicle.
[0015] In the above aspect, a joint that absorbs any vertical
displacement of the first portion of the exhaust pipe that
accompanies the vertical displacement of the muffler may be
provided in the first portion of the exhaust pipe.
[0016] According to the above-noted constitution, when the muffler
is displaced not only toward the rear of the vehicle but also
vertically at the time of a front-end collision, the accompanying
vertical displacement of the first portion of the exhaust pipe is
absorbed by the joint. This makes it possible to avoid interference
of the first portion of the exhaust pipe with the fuel tank by the
vertical displacement of the first portion of the exhaust pipe.
[0017] In the above aspect, a part that bends more easily than
another part of the first portion of the exhaust pipe when the
muffler is vertically displaced may be provided in the first
portion of the exhaust pipe.
[0018] According to the above-noted constitution, when a front-end
collision occurs in a vehicle and the muffler is displaced not only
toward the rear of the vehicle, but vertically, the first portion
of the exhaust pipe is also vertically displaced. With regard to
this displacement, the displacement is restricted by the bending of
a part of the first portion of the exhaust pipe part that bends
more easily than another part of the first portion of the exhaust
pipe. Stated differently, the vertical displacement of the first
portion of the exhaust pipe in concert with the vertical
displacement of the muffler is absorbed by the bending of a part of
the first portion of the exhaust pipe that bends more easily than
another part of the first portion of the exhaust pipe. It is,
therefore, possible to restrict the vertical displacement of the
first portion of the exhaust pipe in concert with vertical
displacement of the muffler, and as a result possible to avoid
interference by the first portion of the exhaust pipe with the fuel
system apparatus caused by vertical displacement of the first
portion of the exhaust pipe.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The foregoing and further objects, features, and advantages
of the invention will become apparent from the following
description of preferred embodiments with reference to the
accompanying drawings, wherein like numerals are used to represent
like elements, and wherein:
[0020] FIG. 1A is a drawing showing an exhaust apparatus mounted
aboard a vehicle viewed from above the vehicle, and FIG. 1B is the
exhaust apparatus viewed from the side of the vehicle;
[0021] FIG. 2 is a simplified drawing showing the movement of the
muffler and the second exhaust pipe part at the time of a front-end
collision;
[0022] FIG. 3 is a simplified drawing showing the movement of the
muffler and the second exhaust pipe part at the time of a front-end
collision; and
[0023] FIG. 4 is a simplified drawing showing another example of a
first exhaust pipe part in exhaust apparatus.
DETAILED DESCRIPTION OF THE EXAMPLE EMBODIMENTS
[0024] Embodiments of an exhaust apparatus according to the present
invention are described below, with reference made to FIG. 1A, FIG.
1B, FIG. 2, and FIG. 3. FIG. 1A is a drawing showing an exhaust
apparatus mounted aboard a vehicle viewed from above the vehicle,
and FIG. 1B is the exhaust apparatus viewed from the side of the
vehicle.
[0025] In the exhaust apparatus, a muffler 3 is provided midway in
an exhaust pipe 2 connected to an internal combustion engine 1
mounted aboard the vehicle, and a first portion 4 of the exhaust
pipe 2 (i.e. an intermediate portion of the exhaust pipe 2 and a
second portion 5 of the exhaust pipe 2 (i.e. a downstream portion
of the exhaust pipe are provided downstream of the muffler 3. The
exhaust pipe 2 (including the first portion 4 and second portion 5)
and the muffler 3 are supported on the lower surface of the
vehicle. Exhaust from the internal combustion engine 1 is
discharged to the outside via the exhaust pipe 2, at which time the
exhaust passes through the muffler 3, the first portion 4 and the
second portion 5 of the exhaust pipe.
[0026] The first portion 4 of the exhaust pipe is connected to the
muffler 3 and extends toward the rear of the vehicle. A fuel system
apparatus (a fuel tank 6 in this embodiment) used to supply fuel to
the internal combustion engine 1 is provided at the rear of the
vehicle. The first portion 4 of the exhaust pipe extends toward the
fuel tank 6. A joint 7 that absorbs vertical displacement of the
first portion 4 of the exhaust pipe in the event that the muffler 3
is displaced vertically is provided midway in the first portion 4
of the exhaust pipe. The joint 7 that is used may be, for example,
a ball joint or a flexible joint that allows free movement of the
first portion 4 of the exhaust pipe about the joint 7.
[0027] The second portion 5 of the exhaust pipe is connected so as
to bend in the horizontal direction (up-down direction in FIG. 1A)
with respect to the first portion 4 of the exhaust pipe, and
extends along the side wall 6a of the fuel tank 6 toward the rear
of the vehicle, while maintaining a prescribed clearance around the
fuel tank 6. The sidewall 6a is substantially perpendicular to the
road surface, the part of the sidewall 6a toward the front of the
vehicle extends at an inclination toward the rear of the vehicle,
and the part of the sidewall 6a toward the rear of the vehicle
extending straight toward the rear of the vehicle. In order to
increase the capacity and to achieve a fuel storage amount, a
portion of the fuel tank 6 bulges out toward the side of the
vehicle and covers the top of the part of the second portion 5 of
the exhaust pipe that extends along the sidewall 6a (upward in FIG.
1A).
[0028] Next, the structure for restricting the displacement of the
muffler 3 toward the rear of the vehicle so that the second portion
5 of the exhaust pipe does not interfere the fuel tank 6 when the
vehicle is subjected to a front-end collision will be described in
detail.
[0029] The vehicle has a plurality of reinforcing cross members
and, of these cross members, a cross member provided further toward
the rear of the vehicle than the muffler 3 is used to restrict the
movement of the muffler 3 toward the rear of the vehicle.
[0030] Specifically, as shown in FIG. 1B, in the vicinity of the
floor 10 of the vehicle and farther to the rear of the vehicle than
the muffler 3, a pair of cross members 8, 9 extending in the width
direction of the vehicle are provided so as to sandwich the first
portion 4 of the exhaust pipe therebetween from the top and bottom.
The cross members 8, 9 function as restricting members. The minimum
distance L1 in the vertical direction of the cross members 8, 9 is
smaller than the maximum height L2 of the muffler 3. That is, at
least one of L1 and L2 may be adjusted to obtain the
above-described relationship between L1 and L2. By doing this, when
the muffler 3 is displaced toward the rear of the vehicle, the
muffler 3 comes into contact with and is caught by the cross
members 8, 9, which restricts the muffler 3 from any further
movement toward the rear of the vehicle.
[0031] The usual distance L3 in the longitudinal direction of the
vehicle between the part of the cross members 8, 9 that catches the
muffler 3 and the part of the muffler 3 that comes into contact
with the cross members 8, 9 is smaller than the minimum distance L4
between the second portion 5 of the exhaust pipe and the sidewall
6a of the fuel tank 6 when the exhaust pipe is mounted abroad the
vehicle. That is, at least one of L3 and L4 may be adjusted so as
to obtain the above-noted relationship between L3 and L4. By doing
this, if the overall exhaust apparatus is displaced toward the rear
of the vehicle, before the second portion 5 of the exhaust pipe
comes into contact with the side wall 6a of the fuel tank 6, the
muffler 3 comes into contact with the cross members 8, 9, which
restricts the muffler 3 from being displaced further toward the
rear of the vehicle.
[0032] Next, the movement of the muffler 3 and the second portion 5
of the exhaust pipe when the vehicle is subjected to a front-end
collision will be described, with reference to FIG. 2 and FIG. 3.
If the vehicle is subjected to a front-end collision that displaces
the internal combustion engine 1 toward the rear of the vehicle,
there is an accompanying displacement of the overall exhaust
apparatus toward the rear of the vehicle (direction of the arrow in
FIG. 2), which causes the second portion 5 of the exhaust pipe to
approach the side wall 6a of the fuel tank 6. Before the second
portion 5 of the exhaust pipe comes into contact with the side wall
6a, however, the muffler 3 comes into contact with the cross
members 8, 9 shown in the same drawings, thereby restricting the
muffler 3 from further movement toward the rear of the vehicle,
which prevents interference with the fuel tank 6 by the second
portion 5 of the exhaust pipe.
[0033] When a front-end collision occurs in a vehicle, the muffler
might be displaced not only toward the rear of the vehicle, but
also vertically. For example, when the muffler 3 is displaced
upwardly as indicated by the arrow in FIG. 3, along with this
displacement that the first portion 4 of the exhaust pipe is also
displaced upwardly. Stated differently, the first portion 4 of the
exhaust pipe approaches the part of the fuel tank 6 that bulges
upward above the first portion 4 of the exhaust pipe (refer to FIG.
1A). With regard to the displacement of the first portion 4 of the
exhaust pipe, however, when the muffler 3 is displaced upward, the
bending of the joint 7, as shown in FIG. 3, restricts the first
portion 4 of the exhaust pipe. This means that the upward
displacement of the first portion 4 of the exhaust pipe
accompanying the upward displacement of the muffler 3 is absorbed
by the joint 7 provided midway in the first portion 4 of the
exhaust pipe. Interference by the upward displacement of the first
portion 4 of the exhaust pipe with the fuel tank 6 is, therefore,
avoided.
[0034] The embodiment described in detail above achieves a number
of effects. The first effect is that, when the vehicle is subjected
to a front-end collision and the overall exhaust apparatus is
displaced toward the rear of the vehicle, the muffler 3 makes
contact with the cross members 8, 9 before making contact with the
side wall 6a, further displacement of the muffler 3 toward the rear
of the vehicle being restricted, which makes it possible to avoid
interference by the second portion 5 of the exhaust pipe with the
fuel tank 6. Also, as a result of establishing underfloor space in
the vehicle, even if it is not possible to achieve a sufficient
distance L4 in the longitudinal direction of the vehicle between
the second portion 5 of the exhaust pipe and the fuel tank 6, by
setting the distance L3 between the muffler 3 and the cross members
8, 9 small in comparison with the distance L4, the above-described
effect is achieved.
[0035] The second effect is that, because the cross members 8, 9
restrict the displacement of the muffler 3 toward the rear of the
vehicle, an additional restricting member need not be provided,
thereby avoiding the additional cost associated with providing an
additional restricting member.
[0036] The third effect is achieved by using a pair of cross
members 8, 9 as cross members that restrict the displacement of the
muffler 3 toward the rear of the vehicle, the cross members 8, 9
sandwiching from the top and bottom the first portion 4 of the
exhaust pipe disposed to the rear of the vehicle from the muffler
3. The distance L1 between the cross members 8, 9 is set to a value
that is smaller than the height L2 of the muffler 3. When the
overall exhaust apparatus is displaced toward the rear of the
vehicle at the time of a front-end collision, therefore, the
muffler 3 catches on the pair of cross members 8, 9 and is
restricted from further displacement toward the rear of the
vehicle. For this reason, it is possible to restrict the first
portion 4 of the exhaust pipe and the second portion 5 of the
exhaust pipe from further displacement toward the rear of the
vehicle.
[0037] The fourth effect is that, in the event of a front-end
collision, when the muffler 3 is displaced not only toward the rear
of the vehicle but also vertically, the accompanying vertical
displacement of the first portion 4 of the exhaust pipe is absorbed
by the joint 7. This makes it possible to avoid interference of the
first portion 4 of the exhaust pipe with the fuel tank 6 by the
vertical displacement of the first portion 4 of the exhaust
pipe.
[0038] The foregoing embodiment may be modified in the following
ways. Although ball joint or flexible joint is given as an example
of the joint 7 that absorbs vertical displacement of the first
portion 4 of the exhaust pipe accompanying vertical displacement of
the muffler 3, a type of joint other than these types may be
used.
[0039] Instead of providing the joint 7 midway in the first portion
4 of the exhaust pipe, a part that is more easily bendable than
another part of the exhaust pipe may be provided midway in the
first exhaust pipe. As shown in FIG. 4, for example, a bending part
4a that is formed like a bellows may form as the easily bendable
part. In this case; the same effect of the above described forth
effect will be obtained.
[0040] It is not necessary to adapt the cross members 8, 9, to
restrict the muffler 3 from moving farther toward the rear of the
vehicle. The first portion 4 of the exhaust pipe may be, for
example, disposed between a part other than the cross member
provided on the vehicle floor 10 and the cross members 8, 9, and
the distance between the part and the cross members in the up-down
direction may be set to a value that is smaller than the height L2
of the muffler 3. In this case, the same effect above described
third effect will be also obtained.
[0041] Instead of using the cross members 8, 9 as the restricting
member for restricting the displacement of the muffler 3 toward the
rear of the vehicle, an additional restricting member may be
provided in the vehicle.
* * * * *