U.S. patent application number 15/139378 was filed with the patent office on 2016-12-08 for construction machine with engine.
This patent application is currently assigned to KOBELCO CONSTRUCTION MACHINERY CO., LTD.. The applicant listed for this patent is KOBELCO CONSTRUCTION MACHINERY CO., LTD.. Invention is credited to Seiichi ONISHI, Kazuhiro UEDA.
Application Number | 20160356017 15/139378 |
Document ID | / |
Family ID | 55910806 |
Filed Date | 2016-12-08 |
United States Patent
Application |
20160356017 |
Kind Code |
A1 |
UEDA; Kazuhiro ; et
al. |
December 8, 2016 |
CONSTRUCTION MACHINE WITH ENGINE
Abstract
Provided is a construction machine including exhaust ducts and
favorably discharging air from an engine room through an air
outlet. The construction machine includes an engine room with an
upper wall portion and a cooling fan, the upper wall portion formed
with first and second exhaust ducts. The first exhaust duct
includes an upstream portion extending in a first horizontal
direction and a downstream portion extending upward from a terminal
end of the upstream portion to a first air outlet. The second
exhaust duct includes a cross portion crossing the upstream portion
in a second horizontal direction perpendicular to the first
horizontal direction above the upstream portion. The cross portion
allows air to flow from a second air inlet opened downward and
sideward of the upstream portion to a second air outlet opposite to
the second air inlet, through an upper side of the upstream
portion.
Inventors: |
UEDA; Kazuhiro; (Hiroshima,
JP) ; ONISHI; Seiichi; (Hiroshima, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KOBELCO CONSTRUCTION MACHINERY CO., LTD. |
Hiroshima-shi |
|
JP |
|
|
Assignee: |
KOBELCO CONSTRUCTION MACHINERY CO.,
LTD.
Hiroshima-shi
JP
|
Family ID: |
55910806 |
Appl. No.: |
15/139378 |
Filed: |
April 27, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E02F 9/0891 20130101;
F01P 2060/16 20130101; B62D 25/12 20130101; B60K 11/06 20130101;
E02F 9/0866 20130101; B60Y 2200/412 20130101; F01P 1/06 20130101;
B62D 25/082 20130101; F01P 2001/005 20130101 |
International
Class: |
E02F 9/08 20060101
E02F009/08; B62D 25/12 20060101 B62D025/12; B60K 11/06 20060101
B60K011/06 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 8, 2015 |
JP |
2015-115375 |
Claims
1. A construction machine, comprising: an engine; an engine room
having an external wall enclosing an internal space for housing the
engine; a cooled object disposed in the internal space of the
engine room; and a cooling fan that is driven to produce cooling
air flow for cooling the cooled object in the internal space of the
engine room, wherein: the external wall of the engine room includes
an upper wall portion located on an upper side of the internal
space, the upper wall portion being formed with a first exhaust
duct, and a second exhaust duct for guiding air inside the internal
space to an outside of the engine room; the first exhaust duct
includes an upstream portion extending in a first horizontal
direction and having one end which forms a first air inlet and a
downstream portion extending upward from a terminal end of the
upstream portion to a first air outlet opened upward in the upper
wall portion, the first exhaust duct allowing air to flow from the
first air inlet to the first air outlet; and the second exhaust
duct includes a cross portion crossing the upstream portion of the
first exhaust duct on an upper side of the upstream portion in a
second horizontal direction perpendicular to the first horizontal
direction, the second exhaust duct having a second air inlet opened
downward at a position sideward of the upstream portion of the
first exhaust duct with respect to the second horizontal direction
and a second air outlet opened sideward at a position opposite to
the air inlet across the cross portion in the upper wall portion,
the cross portion allowing air to flow from the second air inlet to
the second air outlet through an upper side of the upstream portion
of the first exhaust duct.
2. The construction machine according to claim 1, wherein: the
engine has an engine output shaft; the cooling fan includes a
plurality of blades coupled to the engine output shaft so as to be
rotated about a fan rotational axis parallel to an axis of the
engine output shaft; the plurality of blades are rotated to thereby
form an axial flow in a direction parallel to the axial direction
of the engine output shaft and a rotational flow around the axis
parallel to the axial direction of the engine output shaft; and the
first horizontal direction is parallel to the axial direction of
the engine output shaft.
3. The construction machine according to claim 2, wherein the
second air outlet of the second exhaust duct is provided above a
position where a tangential direction of the rotational flow is
upward.
4. The construction machine according to claim 1, wherein the upper
wall portion of the engine room includes at least one shared wall
that configures both a part of a wall of the first exhaust duct and
a part of a wall of the second exhaust duct.
5. The construction machine according to claim 4, wherein the at
least one shared wall includes an upstream partition wall that
vertically partitions the upstream portion of the first exhaust
duct and the cross portion of the second exhaust duct from each
other to configure both of a top wall of the upstream portion and a
bottom wall of the cross portion.
6. The construction machine according to claim 4, wherein the at
least one shared wall includes a downstream partition wall that
partitions the downstream portion of the first exhaust duct and the
cross portion of the second exhaust duct from each other in the
first horizontal direction to configure both a side wall of the
downstream portion and a side wall of the cross portion.
7. The construction machine according to claim 1, wherein: the
upper wall portion includes a pair of opposition side walls opposed
to each other in the second horizontal direction across the
upstream portion of the first exhaust duct therebetween and an
external side wall located on an outer side of one side wall of the
opposition side walls, the one side wall being closer to the second
air inlet; and the opposition side wall closer to the second air
inlet and the external side wall constitute an inlet-side portion
which is a part of the second exhaust duct and located under an
upstream end portion of the cross portion of the second exhaust
duct.
8. The construction machine according to claim 1, wherein the cross
portion of the second exhaust duct has a shape having a size in the
first horizontal direction, the size increasing as the cross
portion extends from the second air inlet toward the second air
outlet.
Description
TECHNICAL FIELD
[0001] The present invention relates to a construction machine
including an engine and an engine room for housing the engine and
having a function of cooling a cooled object within the engine
room.
BACKGROUND ART
[0002] There have been known construction machines such as
hydraulic shovels each including an engine and an engine room for
housing the engine, wherein the engine room houses a cooled object
such as a heat exchanger and a cooling fan producing cooling air
flow for cooling the cooled object. These construction machines
include one having an exhaust duct formed in an external wall
configuring the engine room, such as an engine guard or engine hood
(also called "bonnet") enclosing the internal space of the engine
room, wherein the air produced by the cooling fan to cool the
cooled object is discharged to the outside of the engine room
through the exhaust duct. The exhaust duct has a function of
enabling the air in the engine room to be discharged while
suppressing leakage of the noise of the engine room to the outside
by the shape of a channel formed by the exhaust duct or a sound
absorption member provided on an inner surface of the exhaust
duct.
[0003] For example, FIG. 12 of Japanese Unexamined Patent
Publication No. 2001-193102 shows a construction machine including
an engine, an engine room for housing the engine, and a cooling fan
for producing cooling air flow in the engine room, wherein an
exhaust duct extending horizontally along an axial direction of the
engine is formed in an upper portion of the engine room, allowing
the air of the engine room to be discharged horizontally to the
outside of the engine room through the exhaust duct and an air
outlet formed at the terminal end of the exhaust duct.
[0004] Thus configured construction machine formed with an exhaust
duct and an air outlet in an upper portion of an engine room,
however, may involve a problem that the components located in the
vicinity of the air outlet, such as other devices and structures,
inhibit smooth discharge of the air through the air outlet. For
instance, a construction machine including an exhaust gas treatment
device for purifying the exhaust gas discharged from the engine
housed in the engine room may require the exhaust gas treatment
device to be placed near the air outlet so as to protrude
significantly upward beyond the engine hood, thus preventing the
air from being smooth discharged from the air outlet.
[0005] In order to allow the air from being smooth discharged
through the air outlet regardless of the presence of the exhaust
gas treatment device and the like in the vicinity of the air outlet
of the exhaust duct, the entire exhaust duct including the air
outlet has to have a shape protruding upward beyond the upper end
of the exhaust gas treatment device or the like. Establishing this
shape, however, requires an increased height of the exhaust duct
and further an increased height of the entire engine room, which is
not preferable. In other words, it is difficult to allow the air to
be smooth discharged through the air outlet of the exhaust duct
while giving the engine room a restrained entire height.
[0006] Meanwhile, the exhaust duct is required to have an exhaust
flow path with large area. It is, however, not preferable to simply
enlarge the area of the flow path of the exhaust duct, which
deteriorates the noise suppression effect.
SUMMARY OF INVENTION
[0007] It is an object of the present invention to provide a
construction machine including an engine and an engine room for
housing the engine, the engine room having an upper portion formed
with an exhaust duct, the exhaust duct being capable of allowing
air to be favorably discharged through an air outlet formed at the
terminal end of the exhaust duct and having a large flow path area
without deteriorating the noise suppression effect.
[0008] Provided is a construction machine, including: an engine; an
engine room having an external wall enclosing an internal space for
housing the engine; a cooled object disposed in the internal space
of the engine room; and a cooling fan that is driven to produce
cooling air flow for cooling the cooled object in the internal
space of the engine room. The external wall of the engine room
includes an upper wall portion located on an upper side of the
internal space, the upper wall portion being formed with a first
exhaust duct and a second exhaust duct for guiding air inside the
internal space to an outside of the engine room. The first exhaust
duct includes an upstream portion extending in a first horizontal
direction and having one end which forms a first air inlet and a
downstream portion extending upward from a terminal end of the
upstream portion to a first air outlet opened upward in the upper
wall portion, the first exhaust duct allowing air to flow from the
first air inlet to the first air outlet. The second exhaust duct
includes a cross portion crossing the upstream portion of the first
exhaust duct on an upper side of the upstream portion in a second
horizontal direction perpendicular to the first horizontal
direction, the second exhaust duct having a second air inlet opened
downward at a position sideward of the upstream portion of the
first exhaust duct with respect to the second horizontal direction
and a second air outlet opened laterally at a position opposite to
the air inlet across the cross portion in the upper wall portion.
The cross portion allows air to flow from the second air inlet to
the second air outlet through an upper side of the upstream portion
of the first exhaust duct.
[0009] Note that the expressions "extending in the first horizontal
direction" and "crossing in the second horizontal direction"
specify that each of the upstream portion of the first exhaust duct
and the cross portion of the second exhaust duct has a shape
substantially along a horizontal direction so as to be able to
guide the air in the horizontal direction, not intending to exclude
one whose wall constituting the upstream portion or the cross
portion is inclined with respect to a horizontal surface.
BRIEF DESCRIPTION OF DRAWINGS
[0010] FIG. 1 is a side view of a hydraulic shovel according to an
embodiment of the present invention;
[0011] FIG. 2 is a cross-sectional front view showing an internal
structure of an engine room of the hydraulic shovel, the internal
structure being viewed from the front of an upper slewing body of
the hydraulic shovel;
[0012] FIG. 3 is a partial cross-sectional side view showing the
internal structure of the engine room;
[0013] FIG. 4 is a plan view of an engine hood corresponding to an
upper wall portion of an external wall of the engine room;
[0014] FIG. 5 is a rear view of the engine hood;
[0015] FIG. 6 is a perspective view showing the appearance in which
the engine hood is viewed from above;
[0016] FIG. 7 is a perspective view in which the engine hood is
viewed from below;
[0017] FIG. 8 is a cross-sectional diagram taken along VIII-VIII of
FIG. 5;
[0018] FIG. 9 is a cross-sectional diagram taken along IX-IX of
FIG. 4;
[0019] FIG. 10 is a cross-sectional diagram taken along X-X of FIG.
4; and
[0020] FIG. 11 is a cross-sectional diagram taken along XI-XI of
FIG. 4.
DESCRIPTION OF EMBODIMENTS
[0021] A preferred embodiment of the present invention is now
described with reference to the drawings.
[0022] FIG. 1 shows a hydraulic shovel 10 according to the
embodiment. This hydraulic shovel 10 is an example of a
construction machine to which the present invention is employed.
The construction machine is not limited to the hydraulic shovel 10.
The present invention can be employed widely to construction
machines each including an engine and an engine room for housing
the engine wherein a cooled object and a cooling fan are also
housed in the engine room.
[0023] The hydraulic shovel 10 includes a lower traveling body 12,
an upper slewing body 14 mounted in a revolvable manner on the
lower traveling body 12, and a work attachment 16 supported on the
upper slewing body 14. The upper slewing body 14 includes an
operation room 18, an engine room 20, a counterweight 22.
[0024] The engine room 20 forms a rear portion of the upper slewing
body 14 and houses an engine 24, a hydraulic pump 26, a heat
exchanger 28, a cooling fan 30 and the like, as shown in FIG.
2.
[0025] The engine 24 includes an engine output shaft 25 and is
disposed inside the engine room 20 in such an attitude that the
engine output shaft 25 is parallel to a first horizontal direction
indicated by the arrow A1 in FIG. 2 (and FIGS. 7 to 9), that is, a
lateral direction of the upper slewing body 14 in the present
embodiment. In other words, the engine 24 is laid down in the
engine room 20 in such a horizontal attitude that the engine 24 is
perpendicular to a horizontal direction perpendicular to the first
horizontal direction, namely, a second horizontal direction
indicated by the arrow A2 in FIG. 3 (and FIGS. 7, 8 and 10) or,
that is, a front-back direction of the upper slewing body 14 in the
present embodiment. The hydraulic pump 26 is coupled to the engine
24 and driven by the engine 24 to thereby discharge hydraulic
oil.
[0026] The heat exchanger 28 is a cooled object, which is an object
to be cooled, for example, a radiator.
[0027] The cooling fan 30 has a plurality of blades 31 connected to
the engine output shaft 25 as shown in FIG. 3 and a fan shroud 32
which is not shown in FIG. 3. The plurality of blades 31 are
rotated in synchronization with the rotation of the engine output
shaft 25, thereby forming flows of air for cooling the heat
exchanger 28: specifically, an axial flow Fx from the heat
exchanger 28 to the engine 24 in parallel to the engine output
shaft 25 as shown in FIG. 2 and a rotational flow Fs along the
rotational direction of the plurality of blades 31 around the
engine output shaft 25 as shown in FIG. 3.
[0028] The engine room 20 has an external wall enclosing an
internal space for housing the engine 24 and the like. The external
wall includes an external-wall main body 34 and an engine hood
36.
[0029] The external-wall main body 34 is substantially in the shape
of a rectangular cuboid in the present embodiment and includes a
top wall 35 defining the internal space at upper side thereof. The
top wall 35 is formed with an opening 37 for opening the internal
space upward.
[0030] The engine hood 36, which corresponds to an upper wall
portion on the upper side of the internal space, is attached to the
top wall 35 so as to open and close the opening 37. Specifically,
as shown in FIG. 3, the engine hood 36 is connected to an edge
portion of the top wall 35 by a plurality of hinges 39; the edge
portion is a part of an edge surrounding the opening 37 and located
rearward of the opening 37 (on the right-hand side of FIG. 3). The
hinges 39 support the rear edge of the engine hood 36 so as to
allow the engine hood 36 to make rotational movement about an axis
parallel to the first horizontal direction. The rotational movement
allows the engine hood 36 to move between the closed position in
which the engine hood 36 closes the opening 37 (shown by the solid
line in FIG. 1) and the open position in which the engine hood 36
opens the opening 37 (shown by the two-dot chain line in FIG. 1),
as shown in FIGS. 2 and 3.
[0031] This construction machine also includes an exhaust gas
treatment device 29 for purifying the exhaust gas of the engine 24.
In the present embodiment, the exhaust gas treatment device 29 is
disposed so as to protrude upward beyond the top wall 35, as shown
in FIG. 2, and adjacent to the engine hood 36 on the right side
(the left-hand side of FIG. 2) thereof. FIG. 2 shows only a housing
in the shape of a substantially rectangular cuboid, which is one of
elements included in the exhaust gas treatment device 29.
[0032] The external-wall main body 34 is formed with a
not-graphically shown inlet port through which air outside the
engine room 20 is introduced into the space within the engine room
20. Meanwhile, the engine hood 36 is formed with, as one of the
features of this construction machine, a first exhaust duct 40 and
a second exhaust duct 50 having respective air flow paths
independent from each other. Each of the first and second exhaust
ducts 40, 50 has a function of guiding the air in the internal
space to the outside of the engine room while suppressing leakage
of noise to the outside. The cooling fan 30 is driven to introduce
the outside air into the engine room 20 through the inlet port by
the rotation of the plurality of blades 31 to create the axial flow
Fx and the rotational flow Fs and further to discharge air having
been used to cool the heat exchanger 28 to the outside of the
engine room 20 through the first and second exhaust ducts 40,
50.
[0033] Next will be described the basic configurations of the first
and second exhaust ducts 40, 50 with reference to FIGS. 4 to 11 and
then will be described the members for specifically forming the
first and second exhaust ducts 40, 50.
[0034] The first exhaust duct 40 has an upstream portion 42 and a
downstream portion 44 that are connected to each other in
series.
[0035] The upstream portion 42, which extends in the first
horizontal direction indicated by the arrow A1, is located
downstream of the cooling fan 30 with respect to the direction of
the axial flow Fx created by the cooling fan 30. The upstream
portion 42 has an upstream end (a left end in FIG. 9) and a
downstream end (a right end in FIG. 9), wherein the upstream end
surrounds a first air inlet 46 and the downstream end configures a
terminal end 43 closed with respect to the first horizontal
direction.
[0036] The downstream portion 44 extends upward from the terminal
end 43 of the upstream portion 42. The downstream portion 44 has an
upper end, namely, a downstream end thereof, which reaches a first
air outlet 48. The first air outlet 48 is opened to the outside of
the engine hood 36, specifically, toward the space above the engine
hood 36.
[0037] The first exhaust duct 40 allows air to flow as indicated by
the arrows D11, D12 shown in FIGS. 9 and 11. Specifically, the
first exhaust duct 40 enables the air to flow from the first air
inlet 46 through the inside of the upstream portion 42 along the
first horizontal direction and further to flow upward from the
terminal end 43 of the upstream portion 42 through the inside of
the downstream portion 44 (the arrow D11), thereby allowing the air
to be discharged upward to the outside of the engine hood 36
through the first air outlet 48 (the arrow D12).
[0038] The second exhaust duct 50 includes a cross portion 52. The
cross portion 52 crosses the upstream portion 42 of the first
exhaust duct 40 along the second horizontal direction indicated by
the arrow A2, at a position on the upper side of the upstream
portion 42, preferably a position just above the upstream portion
42.
[0039] The second exhaust duct 50 has a second air inlet 56 and a
second air outlet 58. The second air inlet 56 is opened downward at
a position sideward of the upstream portion 42 of the first exhaust
duct 40 with respect to the second horizontal direction. The second
air outlet 58 is opened toward a space sideward of the engine hood
36 and outside of the engine hood 36, at a position opposite to the
foregoing air inlet across the cross portion 52 of the engine hood
36.
[0040] Specifically, the second exhaust duct 50 according to the
present embodiment has an inlet-side portion 54 in addition to the
cross portion 52. The inlet-side portion 54 is located downward of
an upstream end portion 53 of the cross portion 52 and has a
function of guiding the air of the engine room 20 upward from the
second air inlet 56 to the upstream end portion 53.
[0041] The cross portion 52 enables air to flow as indicated by the
arrows D21, D22 shown in FIG. 10, independently of the upstream
portion 42 and the downstream portion 44 of the first exhaust duct
40. Specifically, the cross portion 52 enables the air introduced
to the upstream end portion 53 to flow along the cross portion 52,
i.e., along the second horizontal direction through the upper side
of the upstream portion 42 of the first exhaust duct 40, to reach
the second air outlet 58 (the arrow D21), thereby allowing the air
to be discharged sideward through the second air outlet 58 (the
arrow D22).
[0042] As the members for constructing the first and second exhaust
ducts 40, 50 described above, the engine hood 36 includes a hood
wall 60, a first duct member 70, a second duct member 80, and an
auxiliary support member 90.
[0043] The hood wall 60, which configures the shell of the engine
hood 36, bulges upward beyond the upper surface of the top wall 35
while closing the opening 37 in the state where the engine hood 36
is in the closed position as shown in FIGS. 2 and 3. The hood wall
60, thus, has a shape enclosing a hood internal space having a
predetermined capacity and located over the opening 37.
[0044] Specifically, the hood wall 60 integrally includes a top
wall portion 61, a front wall portion 62, and a rear wall portion
63. The top wall portion 61 has a curved-surface-like shape
covering continuously the hood internal space at the upper side and
the left-hand side in the upper slewing body 14 (the right-hand
side of FIG. 2 and the left-hand sides of FIGS. 5 and 9). The front
wall portion 62 and the rear wall portion 63 cover the hood
internal space on the front side and rear side in the upper slewing
body 14, respectively, and are integrated with the top wall portion
61 through a smooth curve.
[0045] The hood wall 60, therefore, has a lower edge surrounding a
lower opening located at a lower end of the hood wall 60 and a
right edge surrounding a right opening located at a right end of
the hood wall 60 (the right ends in FIGS. 5 and 9). The lower edge
(precisely, a portion of the lower edge other than a part coupled
to the hinges 39) and the right edge are provided with a lower seal
material 64 and a right seal material 65, respectively. The lower
and right seal materials 64, 65 are made of an elastically
deformable material to serve to seal the hood internal space in the
close state where the engine hood 36 is in the closed position.
Specifically, the lower seal material 64 makes close contact with
an upper surface of an open rim portion surrounding the opening 37
in the top wall 35, in the closed state, and the right seal
material 65 makes close contact with a side wall of the housing of
the exhaust gas treatment device 29, in the closed state.
[0046] As shown in FIGS. 4 to 6, the top wall portion 61 is formed
with a plurality of first openings 66 configuring the first air
outlet 48 of the first exhaust duct 40, and the rear wall portion
63 is formed with a plurality of second openings 68 configuring the
second air outlet 58 of the second exhaust duct 50. In addition to
the plurality of first openings 66, the top wall portion 61 is also
formed with a plurality of auxiliary openings 67 for complement of
the outlet opening area of the second exhaust duct 50 separately
from the second air outlet 58.
[0047] The auxiliary support member 90, which is a member for
auxiliary supporting the first and second duct members 70, 80,
extends in the first horizontal direction along a lower edge of the
rear wall portion 63 of the hood wall 60 and is fixed to the lower
edge.
[0048] The first duct member 70 is a member for forming mainly the
first exhaust duct 40. The first duct member 70 has a bottom plate
portion 71, a first side plate portion 72, a second side plate
portion 73, a connecting plate portion 74, and a vertical plate
portion 75, wherein the bottom plate portion 71, the first and
second side plate portions 72, 73, and the connecting plate portion
74 are formed of a single plate member.
[0049] The bottom plate portion 71 configures a bottom wall of the
upstream portion 42 of the first exhaust duct 40. Specifically, the
bottom plate portion 71 has a flat-plate-like shape extending along
the first horizontal direction and has a smaller width than that of
a lower end opening of the hood wall 60 (the size in the second
horizontal direction).
[0050] The first side plate portion 72 configures a side wall which
is one of the side walls of the upstream portion 42 and located on
opposite side to the second air inlet 56 (on the rear side in the
front-back direction of the upper slewing body 14, in the present
embodiment). Specifically, the first side plate portion 72 is
disposed upright, having a lower end portion integrated with a
front end portion of the boom plate portion 71 and an upper end
portion connected to the auxiliary support member 90.
[0051] The second side plate portion 73 configures a side wall
which is the other side wall of the upstream portion 42 and located
in the vicinity of the second air inlet 56 (the front side of the
upper slewing body 14, in the present embodiment). Specifically,
the second side plate portion 73 is disposed upright while spaced
with the first side plate portion 72 in the second horizontal
direction, having a lower end portion integrated with a rear end
portion of the bottom plate portion 71 and an upper end portion
integrated with the connecting plate portion 74.
[0052] The connecting plate portion 74 configures an auxiliary wall
interconnecting an upper end of the second side plate portion 73
and the front wall portion 62 of the hood wall 60. Specifically,
the connecting plate portion 74 has an inner end portion integrally
joined with the upper end portion of the second side plate portion
73 and an outer end portion connected to the front wall portion 62
of the hood wall 60.
[0053] The vertical plate portion 75 configures a terminal end wall
which closes the terminal end 43 of the upstream portion 42 of the
first exhaust duct 40 with respect to the first horizontal
direction, and also configures a side wall which is one of the side
walls of the downstream portion 44 of the first exhaust duct 40 and
which is connected to the terminal end wall. Specifically, the
vertical plate portion 75 is formed of a single plate member
disposed upright, and is disposed so as to close respective flow
paths formed in the upstream portion 42 and the downstream portion
44, across these portions 42, 44, on the right side in the upper
slewing body 14, (that is, so as to define the right side of the
flow paths).
[0054] The second duct member 80 is a member for forming mainly the
second exhaust duct 50. The second duct member 80 has a bottom
plate portion 81, a first side plate portion 82, and a second side
plate portion 83.
[0055] The bottom plate portion 81 has a shape of a horizontal flat
plate and configures a bottom wall of the cross portion 52 of the
second exhaust duct 50, wherein a part of the bottom plate portion
81 in the first horizontal direction (a right-side portion 81a, in
the present embodiment) configures a top wall of the upstream
portion 42 of the first exhaust duct 40. In other words, the
right-side portion 81a of the bottom plate portion 81 functions as
an upstream partition wall to separate the cross portion 52 and the
upstream portion 42 vertically from each other. The size of the
bottom plate portion 81 in the second horizontal direction is
approximately equivalent to the size of the bottom plate portion 71
of the first duct member 70 in the same direction. Thus kept is a
gap 55 shown in FIG. 7 between the front wall portion 62 and an
edge which is one of the both edges of the bottom plate portion 81
with respect to the second horizontal direction and which is closer
to the front wall portion 62. This gap 55 allows air to flow into
the upstream end portion 53 of the cross portion 52 through the gap
55.
[0056] The first side plate portion 82 configures a side wall which
is one of the side walls of the cross portion 52 and which is
located on the opposite side to the downstream portion 44 of the
first exhaust duct 40 (on the left-hand side of the upper slewing
body 14, in the present embodiment). Specifically, the first side
plate portion 82 is inclined so as to be displaced outward as
extending upward (on the left-hand side of the upper slewing body
14), having a lower end portion integrally joined with a left end
portion of the bottom plate portion 81 and an upper end portion
connected to the top wall portion 61 of the hood wall 60.
[0057] The second side plate portion 83 configures the other side
wall of the cross portion 52 and also configures a left side wall
of the downstream portion 44 of the first exhaust duct 40, i.e., a
side wall opposed to the vertical plate portion 75. Specifically,
the second side plate portion 83 is disposed upright so as to
function as a downstream partition wall to separate the cross
portion 52 and the downstream portion 44 in the first horizontal
direction from each other, having a lower end portion integrally
joined with a right end portion of the bottom plate portion 81 and
an upper end portion connected to the top wall portion 61 of the
hood wall 60.
[0058] Furthermore, in the present embodiment, the edge which is
one of the both edges of the bottom plate portion 81 in the first
horizontal direction and located on an opposite side to the
downstream portion 44 (the left edges in FIGS. 8 and 9) is inclined
in such a direction that the edge is far away from the downstream
portion 44 in the first horizontal direction as extending toward
the second air outlet 58, and the first side plate portion 82 is
also inclined in the same manner. The cross portion 52 is thus
given such a shape that the width of the cross portion 52, i.e.,
the size thereof in the first horizontal direction, increases as
close to the second air outlet 58, specifically, the shape widen in
the first horizontal direction as close to the second air outlet 58
beyond the upstream portion 42 of the first exhaust duct 40.
[0059] Moreover, the first and second exhaust ducts 40, 50 are
provided with a plurality of sound absorption member to enhance the
effect of suppressing noise of the exhaust ducts 40, 50. The sound
absorption members provided in the first exhaust duct 40 include,
for example, sound absorption members 101, 102, 103, 104, 105, and
106 that are attached to a lower surface of the bottom plate
portion 71, an inner surface of the first side plate portion 72, an
inner surface of the second side plate portion 73, an inner surface
of the vertical plate portion 75, a lower surface of the right-side
portion 81a of the bottom plate portion 81 and an inner surface of
the second side plate portion 83, respectively. The sound
absorption members provided in the second exhaust duct 50 include,
for example, sound absorption members 111, 112, 113, and 114 that
are attached to a lower surface of the bottom plate portion 81,
lower and upper surfaces of the first side plate portion 82, and
the inner surface of the second side plate portion 83,
respectively.
[0060] The foregoing structure, wherein the first exhaust duct 40
includes, in addition to the upstream portion 42 extending in the
first horizontal direction, the downstream portion 44 extending
upward from the terminal end 43 of the upstream portion 42, the
upper end of the downstream portion 44 forming the first air outlet
48 opened upward, allows air to be well discharged through the
first air outlet 48 even if the exhaust gas treatment device 29 or
other components exists in the vicinity of the first air outlet 48.
Moreover, the cross portion 52 of the second exhaust duct 50
different from the first exhaust duct 40 is formed by effective
utilization of a dead space as a result of the shape of the first
exhaust duct 40, i.e., a space immediately above the upstream
portion 42, which is located lateral to the downstream portion 44
(to the left in FIG. 9), the cross portion 52 enabling the air to
flow across the space immediately above the upstream portion 42,
from the second air inlet 56 of the second exhaust duct 50,
independently of the first exhaust duct 40, to reach the second air
outlet 58. This allows both of the first and second exhaust ducts
40, 50 to be arranged without significant increase in the height of
the engine hood 36 or the entire height of the engine room, thereby
allowing a large total exhaust flow path area to be created without
deteriorating the noise suppression effect. In other words,
differently from simple increase in the flow path area of a single
exhaust duct, the increase involving deterioration in the noise
suppression effect, the arrangement of both of the first and second
exhaust ducts 40, 50 by utilization of the dead space enable the
total flow path area to be increased without significant increase
in the size of the engine room and while making the flow path area
of each exhaust duct 40, 50 optimal enough to obtain the noise
suppression effect.
[0061] In addition, the cross portion 52 according to the present
embodiment, having such a shape that the size in the first
horizontal direction increases as extending from the second air
inlet 56 toward the second air outlet 58, can reduce the difference
between respective opening areas of the second air outlet 58 and
the second air inlet 56 to thereby a favorable flow of air in the
second exhaust duct to be ensured even in the case where the
opening area of the plurality of second openings 68 configuring the
second air outlet 58 is limited due to the shape of the engine hood
36, for example, in the case where the vertical size of each of the
second openings 68 is limited due to the presence of the curved
portion of an upper end of the rear wall portion 63.
[0062] Specifically, it is preferred that the difference between
respective opening areas of the second air inlet 56 and the second
air outlet 58 is small because a significantly smaller opening area
of the second air outlet 58 than that of the second air inlet 56
would generate a so-called orifice phenomenon in the second air
outlet 58 to thereby prevent a sufficient noise suppression effect
from being obtained; however, there can be a case where each of the
plurality of second openings 68 configuring the second air outlet
58 is unable to have a large height. On contrast, the cross portion
52 having such a shape that the size thereof in the first
horizontal direction increases as extending from the second air
inlet 56 toward the second air outlet 58 enables the width of the
second air outlet 58 to be greater than the width of the second air
inlet 56 to allow the opening area of the second air outlet 58 to
be close to that of the second air inlet, even with a significant
limitation in increase in the opening area of the second air outlet
58.
[0063] In addition, the engine hood 36 according to the present
embodiment includes a shared wall configuring a part of a wall of
the first exhaust duct 40 while configuring a part of a wall of the
second exhaust duct 50, specifically: the right-side portion 81a of
the bottom plate portion 81 which vertically separates the upstream
portion 42 of the first exhaust duct 40 and the cross portion 52 of
the second exhaust duct 50 from each other to configure both the
top wall of the upstream portion 42 and the bottom wall of the
cross portion 52; and the second side plate portion 83 that
separates the downstream portion 44 of the first exhaust duct 40
and the cross portion 52 of the second exhaust duct 50 in the first
horizontal direction from each other to configure a side wall of
the downstream portion 44 and a side wall of the cross portion 52.
Thus sharing a part of the wall of the first exhaust duct 40 and a
part of the wall of the second exhaust duct 50 allows the weight of
the engine hood 36 to be reduced and allows the engine hood 36 to
have a reduced size by the vicinity of the first and second exhaust
ducts 40, 50 to each other.
[0064] On the other hand, the present embodiment includes: the
second side plate portion 72 which is one of the first and second
side plate portions 72 and 73 opposed to each other in the second
horizontal direction across the upstream portion 42 of the first
exhaust duct 40 therebetween and which is closer to the second air
inlet 56 than the first side plate portion 72; and the front wall
portion 62 of the hood wall 60 located outside the second side
plate portion 73, the second side plate portion 73 and the front
wall portion 62 constituting the inlet-side portion 54 located
below the upstream end portion 53 of the cross portion 52 of the
second exhaust duct 50: this makes it possible to guide the air
flowing under the cross portion 52 to the upstream end portion 53
of the cross portion 52 with no addition of elements.
[0065] The specific structures of the first and second exhaust
ducts according to the present invention are not limited to the
structures according to the foregoing embodiment. The first and
second exhaust ducts may be formed of respective members that are
completely independent from each other.
[0066] The present invention permits the first horizontal direction
and the second horizontal direction to be set freely. Meanwhile, it
is preferable to set the first horizontal direction to be parallel
to the axial direction of the engine output shaft 25 as described
above. This arrangement enables the axial flow Fx generated by the
cooling fan 30 to promote the flow of air into the upstream portion
42 of the first exhaust duct 40 and also enables the rotational
flow Fs generated by the cooling fan 30 to promote the flow of air
in the cross portion 52 of the second exhaust duct 50.
[0067] In this case, it is further preferable that the second air
outlet 58 be provided above a position where a tangential direction
of the rotational flow Fs is upward (on the left-hand side in FIGS.
3 and 10), as shown in FIGS. 3, 10 and the like. This allows the
discharge of air through the second air outlet 58 to be further
enhanced.
[0068] The upstream portion of the first exhaust duct and the cross
portion of the second exhaust duct according to the invention do
not have to be completely horizontal. These portions may be more or
less inclined, provided as long as these portions can possess the
function of guiding the air along substantially the horizontal
direction.
[0069] As described above, provided is a construction machine
including an engine and an engine room for housing the engine, the
engine room having an upper portion formed with an exhaust duct,
the exhaust duct being capable of allowing air to be favorably
discharged through an air outlet formed at the terminal end of the
exhaust duct and having a large flow path area without
deteriorating the noise suppression effect.
[0070] Provided is a construction machine, including: an engine; an
engine room having an external wall enclosing an internal space for
housing the engine; a cooled object disposed in the internal space
of the engine room; and a cooling fan that is driven to produce
cooling air flow for cooling the cooled object in the internal
space of the engine room. The external wall of the engine room
includes an upper wall portion located on an upper side of the
internal space, the upper wall portion being formed with a first
exhaust duct and a second exhaust duct for guiding air inside the
internal space to an outside of the engine room. The first exhaust
duct includes an upstream portion extending in a first horizontal
direction and having one end which forms a first air inlet and a
downstream portion extending upward from a terminal end of the
upstream portion to a first air outlet opened upward in the upper
wall portion, the first exhaust duct allowing air to flow from the
first air inlet to the first air outlet. The second exhaust duct
includes a cross portion crossing the upstream portion of the first
exhaust duct on an upper side of the upstream portion in a second
horizontal direction perpendicular to the first horizontal
direction, the second exhaust duct having a second air inlet opened
downward at a position sideward of the upstream portion of the
first exhaust duct with respect to the second horizontal direction
and a second air outlet opened laterally at a position opposite to
the air inlet across the cross portion in the upper wall portion.
The cross portion allows air to flow from the second air inlet to
the second air outlet through an upper side of the upstream portion
of the first exhaust duct.
[0071] Note that the expressions "extending in the first horizontal
direction" and "crossing in the second horizontal direction"
specify that each of the upstream portion of the first exhaust duct
and the cross portion of the second exhaust duct has a shape
substantially along a horizontal direction so as to be able to
guide the air in the horizontal direction, not intending to exclude
one whose wall constituting the upstream portion or the cross
portion is inclined with respect to a horizontal surface.
[0072] According to this construction machine, the first exhaust
duct includes, in addition to the upstream portion extending in the
first horizontal direction, the downstream portion extending upward
from the terminal end of this upstream portion, the downstream
portion having an upper end which configures the first air outlet
that is opened upward; this allows air to be favorably discharged
through the first air outlet, even if other devices and structures
exists in the vicinity of the first air outlet. Moreover, the cross
portion of the second exhaust duct different from the first exhaust
duct is formed with effective utilization of a dead space formed
due to the shape of the first exhaust duct, i.e., a space located
immediately above the upstream portion and sideward of the
downstream portion, the cross portion allowing the air to flow
across the space immediately above the upstream portion, from the
second air inlet of the second exhaust duct, to reach the second
air outlet; this allows the first and second exhaust ducts to be
arranged independently from each other without significant increase
in the entire height of the engine room. This makes it possible,
differently from enlarging the flow path area of a single exhaust
duct, to create a large total flow path area of the first and
second exhaust ducts without deteriorating the noise suppression
effect.
[0073] In the case of the construction machine where the engine has
an engine output shaft and the cooling fan includes a plurality of
blades that are coupled to the engine output shaft so as to be
rotated about a fan rotational axis parallel to the axial direction
of the engine output shaft, and where the plurality of blades is
rotated to thereby form an axial flow in a direction parallel to an
axial direction of the engine output shaft and a rotational flow
around the axis parallel to the axial direction of the engine
output shaft, it is preferred that the first horizontal direction
be parallel to the axial direction of the engine output shaft. Of
the flows of air formed by the cooling fan, the axial flow in the
direction parallel to the axial direction of the engine output
shaft, that is, in the first horizontal direction, promotes the
flow of air to the upstream portion of the first exhaust duct
extending in the first horizontal direction, while the presence of
the rotational flow around the axis parallel to the first
horizontal direction promotes the flow of air in the cross portion
of the second exhaust duct crossing the upstream portion in the
second horizontal direction perpendicular to the first horizontal
direction, on the upper side thereof.
[0074] In this case, it is more preferable that the second air
outlet of the second exhaust duct be provided upward of the
position where the tangential direction of the rotational flow is
upward. This makes the promotion of the discharge of the rotational
flow of air through the second air more remarked.
[0075] Although the first and second exhaust ducts may be formed
from members that are completely independent from each other, it is
more preferable that the upper wall portion of the engine room
include at least one shared wall that configures both a part of a
wall of the first exhaust duct and a part of a wall of the second
exhaust duct. Inclusion of the shared wall, i.e., the share of a
part of the wall of the first exhaust duct and a part of the wall
of the second exhaust duct, contributes to reduced weight of the
upper wall portion and further contribute reduced size of the upper
wall portion by arrangement of the first and second exhaust ducts
close to each other.
[0076] Preferable examples of the at least one shared wall
described above include: an upstream partition wall that vertically
separates the upstream portion of the first exhaust duct and the
cross portion of the second exhaust duct from each other to
configure both of the top wall of the upstream portion and the
bottom wall of the cross portion; and a downstream partition wall
that separates the downstream portion of the first exhaust duct and
the cross portion of the second exhaust duct from each other in the
first horizontal direction to configure both of a side wall of the
downstream portion and a side wall of the cross portion.
[0077] It is also preferable: that the upper wall portion includes
a pair of opposition side walls opposed to each other in the second
horizontal direction across the upstream portion of the first
exhaust duct therebetween and an external side wall located on an
outer side of one side wall of the opposition side walls, the one
side wall being closer to the second air inlet; and that the
opposition side wall closer to the second air inlet and the
external side wall constitute an inlet-side portion which is a part
of the second exhaust duct and located under an upstream end
portion of the cross portion of the second exhaust duct. This
inlet-side portion is capable of guiding the air flowing under the
cross portion to the upstream end portion of the cross portion.
[0078] The specific shapes of the first and second exhaust ducts
can be set as appropriate: it is preferable that the cross portion
of the second exhaust duct has a shape having a size in the first
horizontal direction, the size increasing as the cross portion
extends from the second air inlet toward the second air outlet. The
shape makes it possible to create a favorable flow of air in the
second exhaust duct by reducing the difference between the opening
area of the second air outlet and the opening area of the second
air inlet, even in the case where the shape of the upper wall
portion imposes a limitation in the opening area of the second air
outlet opened in the upper wall portion. If the opening area of the
second air outlet was significantly smaller than the opening area
of the second air inlet, a so-called orifice phenomenon would occur
in the second air outlet to prevent a noise suppressing effect from
being sufficiently obtained; in contrast, the shape of the cross
portion having a size in the first horizontal direction, the size
increasing as the cross portion extends from the second air inlet
toward the second air outlet as described above, allows the opening
area of the second air outlet to be close to the opening area of
the second air inlet, regardless of the limitation in increasing
the opening area of the second air outlet.
[0079] This application is based on Japanese Patent application No.
2015-115375 filed in Japan Patent Office on Jun. 8, 2015, the
contents of which are hereby incorporated by reference.
[0080] Although the present invention has been fully described by
way of example with reference to the accompanying drawings, it is
to be understood that various changes and modifications will be
apparent to those skilled in the art. Therefore, unless otherwise
such changes and modifications depart from the scope of the present
invention hereinafter defined, they should be construed as being
included therein.
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