U.S. patent application number 11/983608 was filed with the patent office on 2008-05-15 for vehicle air conditioner.
This patent application is currently assigned to DENSO Corporation. Invention is credited to Eiji Honda, Masami Iwasaki.
Application Number | 20080110201 11/983608 |
Document ID | / |
Family ID | 39367875 |
Filed Date | 2008-05-15 |
United States Patent
Application |
20080110201 |
Kind Code |
A1 |
Honda; Eiji ; et
al. |
May 15, 2008 |
Vehicle air conditioner
Abstract
A vehicle air conditioner comprises: a case 21 that is disposed
in an interior-cabin space 15 formed in a cabin 10 and that forms
an air passage through which air flows; and a heat exchanger 24
that is accommodated in the case 21 and that exchanges heat with
the air, wherein the case 21 is disposed adjacent to a surrounding
wall section 12 of the cabin 10, a case side opening 40 that is
opened and closed by a case side cover 41 is formed in a region of
the case 21 adjacent to the surrounding wall section 12, the case
side opening 40 overlaps a cabin side opening 42 that is provided
in the surrounding wall section 12 and that is opened and closed by
a cabin side cover 43, and a heat exchange core section 24a of the
heat exchanger 24 faces the case side opening 40. Therefore, the
heat exchanger 24 can be inspected and cleaned from the outside of
the cabin 10 while the heat exchanger 24 remains accommodated in
the case 21, and thus, the heat exchanger 24 of the vehicle air
conditioner can be inspected and easily cleaned.
Inventors: |
Honda; Eiji; (Kariya-city,
JP) ; Iwasaki; Masami; (Kariya-city, JP) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, P.L.C.
P.O. BOX 828
BLOOMFIELD HILLS
MI
48303
US
|
Assignee: |
DENSO Corporation
Kariya-city
JP
|
Family ID: |
39367875 |
Appl. No.: |
11/983608 |
Filed: |
November 12, 2007 |
Current U.S.
Class: |
62/515 |
Current CPC
Class: |
B60H 1/00514 20130101;
B60H 1/00378 20130101 |
Class at
Publication: |
062/515 |
International
Class: |
F25B 39/02 20060101
F25B039/02 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 13, 2006 |
JP |
2006-306482 |
Claims
1. A vehicle air conditioner comprising: a case that is disposed in
an interior-cabin space formed in a cabin and that forms an air
passage through which air flows; and a heat exchanger that is
accommodated in said case and that exchanges heat with the air,
wherein said case is disposed adjacent to a surrounding wall
section of said cabin, a case side opening that is opened and
closed by a case side cover in a region of said case adjacent to
said surrounding wall section, said case side opening overlaps a
cabin side opening that is provided in said surrounding wall
section and that is opened and closed by a cabin side cover, and a
heat exchange core section of said heat exchanger faces said case
side opening.
2. A vehicle air conditioner according to claim 1, wherein an air
flow upstream portion of said heat exchange core section faces said
case side opening.
3. A vehicle air conditioner according to claim 1, wherein said
surrounding wall section is a rear wall section of said cabin, said
case is disposed rearward in said cabin, and said heat exchanger is
disposed rearward in said case.
4. A vehicle air conditioner according to claim 1, wherein an area
of said case side cover is smaller than that of said cabin side
opening, said case side cover is removably attached to said case,
and said case side opening is opened and closed when said case side
cover is attached and removed, respectively.
5. A vehicle air conditioner according to claim 1, wherein an area
of said case side cover is smaller than that of said cabin side
opening, said case side cover is swingably supported with respect
to said case in a direction orthogonal to the opening direction of
said case side opening, said case side opening is opened and closed
by swinging said case side cover, and, further, when said case side
cover is swung in a direction to open said case side opening, said
case side cover protrudes to the outside of said cabin through said
cabin side opening.
6. A vehicle air conditioner according to claim 1, wherein said
case side cover is supported and can be shifted with respect to
said case in a direction orthogonal to the opening direction of
said case side opening, said case side opening is opened and closed
by translating said case side cover, and, further, said case side
cover is shifted in said interior-cabin space (15).
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a vehicle air conditioner
that is preferably used in a construction machine such as a
hydraulic excavator, etc.
[0003] 2. Description of the Related Art
[0004] Conventionally, in a vehicle air conditioner, a cooling heat
exchanger (an evaporator) is accommodated in the case of an
interior-cabin air conditioning unit, and when inspected and
cleaned (maintained), the cooling heat exchanger has to be
inspected and cleaned in a narrow interior-cabin space after taking
it out from the case of the air conditioning unit. As a result, it
takes a great deal of time to inspect and clean the cooling heat
exchanger.
[0005] Therefore, a cooling heat exchanger in a vehicle air
conditioner that can be inspected and cleaned in a short period of
time is proposed in Japanese Unexamined Utility Model Publication
No. H05-56516. In the prior art, in a vehicle such as a truck, for
example, in which the air conditioning unit is disposed immediately
rearward of a front shell plate of the vehicle, both a front side
of the case of the air conditioning unit and the front shell plate
of the vehicle are provided with respective overlapping openings
for taking out the cooling heat exchanger so that respective covers
covering openings can be opened and closed.
[0006] Therefore, when the cooling heat exchanger is inspected and
cleaned, first, both covers are opened, and then, the cooling heat
exchanger is removed from the case of the air conditioning unit
through both openings to the forward (outside) of the vehicle.
[0007] Thus, in this prior art, the cooling heat exchanger is
removed to the outside of the vehicle, and therefore, removing the
cooling heat exchanger in a narrow interior-cabin space does not
have to be performed, which results in reduced time for inspecting
and cleaning of the cooling heat exchanger.
[0008] However, in the prior art described above in which the
cooling heat exchanger is removed from the case of the air
conditioner unit, it takes time and effort to remove refrigerant
pipes from the cooling heat exchanger. Further, it also takes time
and effort to drain refrigerant from the vehicle air conditioner
before removing the refrigerant pipes.
[0009] In particular, in a construction machine such as a hydraulic
excavator, which is used in a sandy or dusty environment, etc., a
heat exchange core section of the cooling heat exchanger may become
clogged due to dust adhering to the clearance between the fins of
the cooling heat exchanger. Therefore, the cooling heat exchanger
has to be inspected and cleaned more frequently, and as a result,
the above problem becomes more complicated.
[0010] Further, the above problem not only occurs in the cooling
heat exchanger, but also in a heating heat exchanger.
SUMMARY OF THE INVENTION
[0011] In view of the above problem, it is an object of the present
invention to provide a vehicle air conditioner in which a heat
exchanger can be inspected and easily cleaned.
[0012] In order to achieve the above object, according to the
present invention, there is provided a vehicle air conditioner
comprising:
[0013] a case (21) that is disposed in an interior-cabin space (15)
formed in a cabin (10) and forms an air passage through which air
flows; and
[0014] a heat exchanger (24) that is accommodated in the case (21)
and exchanges heat with the air,
[0015] wherein the case (21) is disposed adjacent to a surrounding
wall section (12) of the cabin (10),
[0016] a case side opening (40) that is opened and closed by a case
side cover (41) is formed in a region of the case (21) adjacent to
the surrounding wall section (12),
[0017] the case side opening (40) overlaps a cabin side opening
(42) that is provided in the surrounding wall section (12) and is
opened and closed by a cabin side cover (43), and
[0018] a heat exchange core section (24a) of the heat exchanger
(24) faces the case side opening (40).
[0019] In this vehicle air conditioner, the heat exchange core
section (24a) of the heat exchanger (24) can be exposed to the
outside of the cabin (10) by opening the case side opening (40) and
cabin side opening (42).
[0020] In other words, the heat exchange core section (24a) of the
heat exchanger (24) can be inspected and cleaned from the outside
of the cabin (10) while the heat exchanger (24) remains
accommodated in the case (21).
[0021] Therefore, when the heat exchanger (24) is inspected and
cleaned, the heat exchanger (24) does not have to be taken out from
the case (21). Further, the heat exchanger (24) does not have to be
inspected and cleaned in the narrow cabin (10). As a result, the
heat exchanger (24) can be inspected and easily cleaned.
[0022] When the heat exchanger (24) is inspected and cleaned, the
case side opening (40) and the cabin side opening (42) can be
closed by the case side cover (41) and the cabin side cover (43),
and therefore, the case side opening (40) does not impede air
passing through the case (21) and the cabin side opening (42) does
not limit cabin space of the cabin (10) (i.e. interior-cabin space
(15)).
[0023] In the vehicle air conditioner according to the present
invention, specifically, an air flow upstream portion of the heat
exchange core section (24a) faces the case side opening (40), and
therefore, the air flow upstream portion of the heat exchange core
section (24a) that is more likely to be covered with dust can be
inspected and easily cleaned.
[0024] Further, in the vehicle air conditioner according to the
present invention, specifically, the surrounding wall section is a
rear wall section (12) of the cabin (10),
[0025] the case (21) is disposed rearward in the cabin (10),
and
[0026] the heat exchanger (24) is disposed rearward in the case
(21).
[0027] Therefore, the heat exchanger (24) can be inspected and
cleaned from the rearward of the cabin (10).
[0028] Still further, in the vehicle air conditioner according to
the present invention, specifically, an area of the case side cover
(41) is smaller than that of the cabin side opening (42),
[0029] the case side cover (41) is removably attached to the case
(21), and
[0030] the case side opening (40) is opened and closed when the
case side cover (41) is attached and removed, respectively.
[0031] The case side opening (40) is then opened and closed when
the case side cover (41) is attached and removed, respectively, and
therefore, the opening/closing structure of the case side opening
(40) can be simplified.
[0032] Still further, an area of the case side cover (41) is
smaller than that of the cabin side opening (42), and therefore,
the removed case side cover (41) can be removed to the outside of
the cabin (10) through the cabin side opening (42). Therefore, the
removed case side cover (41) does not interfere with the inspection
and cleaning of the heat exchanger (24).
[0033] Still further, in the vehicle air conditioner according to
the present invention, specifically, an area of the case side cover
(41) is smaller than that of the cabin side opening (42),
[0034] the case side cover (41) is swingably supported with respect
to the case (21) in a direction orthogonal to the opening direction
of the case side opening (40),
[0035] the case side opening (40) is opened and closed by swinging
the case side cover (41), and,
[0036] further, when the case side cover (41) is swung in a
direction to open the case side opening (40), the case side cover
(41) may protrude to the outside of the cabin (10) through the
cabin side opening (42).
[0037] Therefore, the case side opening (40) can be easily opened
and closed by the case side cover (41).
[0038] Still further, in the vehicle air conditioner according to
the present invention, specifically, the case side cover (41) is
supported and can be shifted with respect to the case (21) in a
direction orthogonal to the opening direction of the case side
opening (40),
[0039] the case side opening (40) is opened and closed by
translating the case side cover (41), and,
[0040] further, the case side cover (41) may be shifted in the
interior-cabin space (15).
[0041] The reference numerals in parentheses affixed to the means
set forth in this section correspond to the specific means set
forth in embodiments described below.
[0042] The present invention may be more fully understood from the
description of the preferred embodiments of the invention, as set
forth below, together with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] In the drawings:
[0044] FIG. 1 is a schematic cross-sectional view of a cabin of a
hydraulic excavator according to a first embodiment of the present
invention;
[0045] FIGS. 2A and 2B are a plan view and rear view, respectively,
of an air conditioning unit shown in FIG. 1;
[0046] FIG. 3 is a cross-sectional view taken along the line A-A in
FIG. 2B;
[0047] FIG. 4 is a schematic cross-sectional view of a cabin of a
hydraulic excavator according to a second embodiment of the present
invention; and
[0048] FIG. 5 is a schematic cross-sectional view of a cabin of a
hydraulic excavator according to a third embodiment of the present
invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
First Embodiment
[0049] FIGS. 1-3 show a first embodiment of the present invention,
in which a vehicle air conditioner according to the present
invention is applied to a construction machine, or more
specifically, a hydraulic excavator. FIG. 1 is a schematic
cross-sectional view of a cabin (an operator's cage) of a hydraulic
excavator according to this embodiment; FIGS. 2A and 2B are a plan
view and rear view, respectively, of an air conditioning unit in
FIG. 1; and FIG. 3 is a cross-sectional view taken along the line
A-A in FIG. 2B. In FIGS. 1-3, arrows marked with "Front", "Rear",
"Top", "Bottom", "Left" and "Right" designate respective directions
in the cabin.
[0050] A cabin 10 of a hydraulic excavator has a surrounding wall
section comprised of a front wall section 11, a rear wall section
12, a ceiling wall section 13, a floor wall section 14 and left and
right side wall sections (not shown), and the cabin 10 forms an
interior-cabin space 15 surrounded by the surrounding wall section.
An upper part of the front wall section 11 is comprised of a front
windshield 16 and an upper part of the rear wall section is
comprised of a rear windshield 17. At least one of the left and
right side wall sections is provided with an operator's door (not
shown).
[0051] A seat 18 on which the operator of the hydraulic excavator
sits is disposed substantially in the center of the floor section
14. An air conditioning unit 20 is disposed at a position rearward
and downward from the seat 18, i.e., at a rearmost and downmost
position of the interior-cabin space 15. It should be noted that
the shape of the air conditioning unit 20 is shown in a simplified
manner in FIG. 1 for convenience of illustration.
[0052] Next, a specific configuration of the air conditioning unit
20 will be described. The air conditioning unit 20 has a box-shaped
case 21 and an air passage through which air flows is formed inside
the case 21.
[0053] The case 21 is molded of a resin material such as
polypropylene that has elasticity to some extent and excellent
strength wherein the case 21 is molded with a plurality of divided
cases for convenience of molding. Then, the case 21 is constructed
by integrally fastening the plurality of divided cases by using
fastening means such as screws, metal spring clips and the
like.
[0054] In this example, a blower section 22 is integrally disposed
on the side wall section of the case 21. This blower section 22 has
a centrifugal blower fan 22b that is rotated by a motor 22a, and a
scroll casing 22c that accommodates the blower fan 22b.
[0055] A rotational axis (not shown) of the blower fan 22b is
disposed vertically, and therefore, an air inlet section 22d of the
blower section 22 is disposed on a top surface section of the
scroll casing 22c. An air outlet section 22e of the blower section
22 is opened rearward of the scroll casing 22c (downward in FIG.
2A) toward the case 21 (the right side in FIG. 2A).
[0056] An inside/outside air switching box 23 for switchably
introducing inside and outside air is disposed on a top surface
section of the blower section 22. The inside/outside air switching
box 23 is provided with an outside air introduction opening 23a
formed on a rear wall section thereof and the outside air
introduction opening 23a is opened and closed by an outside air
door (a plate-like door, not shown). On the other hand, the
inside/outside air switching box 23 is also provided with an inside
air introduction opening 23b formed on a front wall section thereof
and the inside air introduction opening 23b is opened and closed by
an inside air door (a plate-like door, not shown).
[0057] In this example, an electric actuator comprising a servo
motor (not shown) is used as a driving mechanism for rotating the
outside air door and the inside air door. Alternatively, as the
driving mechanism for the outside air door and the inside air door,
it may be possible to use a manual operation mechanism for
transferring manual operating force of an inside/outside air
switching operation member (for example, a manual operation lever)
provided on an air conditioner operation panel (not shown) to
respective rotational axes of the doors via a cable, a link
mechanism and the like.
[0058] In an outside air introduction mode, the outside air door is
operated to a position where the outside air introduction opening
23a is fully opened and the inside air door is operated to a
position where the inside air introduction opening 23b is fully
closed. Therefore, the outside air is introduced into the
inside/outside air changing box 23 from the outside air
introduction opening 23a via an outside air port and an outside air
duct (not shown).
[0059] On the other hand, in an inside air introduction mode, the
outside air introduction opening is operated to a position where
the outside air introduction opening is fully closed and the inside
air door is operated to a position where the inside air
introduction opening 23b is fully opened. Therefore, the inside air
is introduced into the inside/outside air changing box 23 from the
inside air introduction opening 23b.
[0060] Further, in an inside/outside air introduction mode, both
the outside air door and the inside air door are operated to the
positions where the outside air introduction opening 23a and the
inside air introduction opening 23b are fully opened. Therefore,
the outside and inside air is introduced into the inside/outside
air changing box 23 from the outside air introduction opening 23a
and the inside air introduction opening 23b.
[0061] At a rearward position in the case 21 (in a rightward
position in FIG. 3), a substantially rectangular-shaped cooling
heat exchanger 24 is disposed substantially vertically across the
entire length of the case 21. Therefore, an inflow space 25 is
formed between the cooling heat exchanger 24 and a rear wall
section 21a of the case 21 and the air (the inside/outside air)
sent from the air outlet section 22e of the blower section 22
toward the case 21 flows into the inflow space 25.
[0062] Therefore, the whole of the air (the inside/outside air)
flowing into the case 21 from the air outlet section 22e of the
blower section 22 passes through the cooling heat exchanger 24
after the inflow space 25 as indicated by arrow a.
[0063] The cooling heat exchanger 24 is an evaporator in a
refrigeration cycle that has a heat exchange core section 24a
comprising: a plurality of tubes through which a refrigerant
passes; and fins that are joined to outer surfaces of the tubes. As
air passes through clearance in this heat exchange core section
24a, the cold low-pressure refrigerant in the refrigeration cycle
absorbs heat from the passing air and evaporates to cool the
air.
[0064] The cooling heat exchanger 24 in this example has, at its
top and bottom ends, tank sections 24b for distributing or
collecting the refrigerant into/from the plurality of tubes.
[0065] A compressor (not shown) for circulating the refrigerant in
the refrigeration cycle is driven by an engine (not shown) of the
hydraulic excavator via an electromagnetic clutch.
[0066] Inside the case 21, a substantially rectangular-shaped
heating heat exchanger 26 is disposed at the air flow downstream
(vehicle forward) of the cooling heat exchanger 24 and at the
bottom side of the case 21. The heating heat exchanger 26 is
disposed across the entire width of the case 21.
[0067] The heating heat exchanger 26 is a hot water heat exchanger
that heats the air by using cooling water (hot water) for the
engine of the hydraulic excavator as a heat source and that has a
heat exchange core section 26a comprising: a plurality of tubes
through which the hot water passes; and fins that are joined to
outer surfaces of the tubes. As the air from a heater passage 36
passes through clearance in this heat exchange core section 26a,
the air is heated.
[0068] The heating heat exchanger 26 in this example is a so-called
full-pass type heat exchanger that has, at its top and bottom ends,
tank sections 26b for distributing or collecting the hot water
into/from the plurality of tubes, wherein the tank section at the
bottom end constitutes a hot water inlet tank section.
[0069] A plate-like air mix door 27 is disposed above the heating
heat exchanger 26 and a rotational axis 27a of the air mix door 27
is disposed near the top end of the heating heat exchanger 26.
[0070] The rotational axis 27a of the air mix door 27 is disposed
so as to extend in the vertical direction with respect to the
drawing plane of FIG. 3 (in the vehicle width direction) and both
ends of the rotational axis 27a are rotatably held by bearing holes
(not shown) in the left and right side walls of the case 21. One
end of the rotational axis 27a protrudes outside the case 21 to be
coupled to a driving mechanism (not shown).
[0071] Inside the case 21, at the air flow downstream of the
cooling heat exchanger 24 and above the heating heat exchanger 26,
there is formed a cool air bypass passage 28 that allows the cool
air to bypass the heating heat exchanger 26 and flow as indicated
by arrow b. On the other hand, inside the case 21, at the air flow
downstream of the heating heat exchanger 26 (forward of the
vehicle), there is formed a warm air passage 29 through which the
warm air heated in the heating heat exchanger 26 flows as indicated
by arrow c.
[0072] In a region at the vehicle forward of the heating heat
exchanger 26, a warm air guide wall 31 that protrudes from the
bottom surface 21b of the case 21 is formed integrally with the
case 21. This warm air guide wall 31 delimits a space at the
vehicle forward of the warm air passage 29 and guides the warm air
flow in the warm air passage 29 toward the cool air bypass passage
28, as indicated by arrow c.
[0073] As a result, in a region above the warm air passage 29 and
around a tip of the warm air guide wall 31, there is formed an air
mixing section 32 that can satisfactorily mix the warm air and the
cool air with each other.
[0074] In FIG. 3, a position of the air mix door 27 indicated by
solid lines is a maximum cooling position where the air passage of
the heating heat exchanger 26 is fully closed and the cool air
bypass passage 28 is fully opened, and on the other hand, another
position thereof indicated by chain double-dashed lines is a
maximum heating position where the cool air bypass passage 28 is
fully closed and the air passage of the heating heat exchanger 26
is fully opened.
[0075] As well known, the air mix door 27 is a temperature
adjustment means for adjusting temperature of the air flowing into
the cabin by adjusting the flow ratio between the warm air passing
through the heating heat exchanger 26 (arrow c) and the cool air
bypassing the heating heat exchanger 26 and passing through the
cool air bypass passage 28 (arrow b). Then, the above-mentioned
warm air (arrow c) and the above-mentioned cool air (arrow b) are
mixed with each other in the air mixing section 32 so as to obtain
the air of a desired temperature.
[0076] Inside the case 21, above the cool air bypass passage 28,
there is formed a face/defroster passage 33 that communicates with
the air mixing section 32. This face/defroster passage 33 is
configured to extend from the vehicle forward to the vehicle
rearward. A front face/defroster opening 34 is opened in a vehicle
forward position on the side wall of the face/defroster passage 33.
Further, a rear face/defroster opening 35 is opened in a vehicle
rearward position on the top surface of the face/defroster passage
33.
[0077] The front face/defroster opening 34 is connected with a
front face/defroster duct (not shown) that extends in the vehicle
forward direction, so that the air is blown out toward the face of
the operator and the front windshield 16 through a front face
blowout and a defroster blowout at the downstream end of the front
face/defroster duct.
[0078] In this connection, the front face blowout and the defroster
blowout are provided with respective shutter mechanisms (not
shown), so that the front face blowout and the defroster blowout
can be opened and closed independently of each other by the shutter
mechanisms. These shutter mechanisms are operated to be opened and
closed manually by the operator.
[0079] The rear face opening 35 is connected to a rear face duct
(not shown) that extends upward, so that the air is blown out
toward the face of the operator through a rear face blowout at the
downstream end of the rear face duct.
[0080] Inside the case 21, at the vehicle forward of the warm air
passage 29, there is formed a foot passage 36 that communicates
with the air mixing section 32. This foot passage 36 is configured
to extend from the top side to the bottom side.
[0081] A foot opening 37 is opened in the front wall at the lower
part of the foot passage 36. The foot opening 37 is connected to a
foot duct (not shown) that extends in the vehicle forward
direction, so that the air is blown out around the feet of the
operator through a foot blowout at the downstream end of this foot
duct.
[0082] At the vehicle forward of the air mixing section 32, there
is disposed a plate-like blowout mode switching door 38 that
switchably opens and closes the face/defroster passage 33 and the
foot passage 36. A rotational axis 38a of the blowout mode
switching door 38 is disposed so as to extend in the vertical
direction with respect to the drawing plane of FIG. 3 (in the
vehicle width direction) and both ends of the rotational axis 38a
are rotatably held by bearing holes (not shown) in the left and
right side walls of the case 21. One end of the rotational axis 38a
protrudes outside the case 21 to be coupled to a driving mechanism
(not shown).
[0083] In FIG. 3, a position of the blowout mode switching door 38
indicated by solid lines is a position in a face/defroster mode
where the foot passage 36 is fully closed and the face/defroster
passage 33 is fully opened. In contrast to this, a position of the
blowout mode switching door 38 indicated by chain double-dashed
lines is a position in a foot mode where the foot passage 36 is
fully opened and the face/defroster passage 33 is fully closed.
[0084] Further, a plate-like rear face door 39 opens and closes the
rear face opening 35 so as to adjust the flow ratio between the air
blown out from the front face blowout and the defroster blowout and
the air blown out from the rear face blowout.
[0085] A rotational axis 39a of the rear face door 39 is disposed
so as to extend in the vertical direction with respect to the
drawing plane of FIG. 3 (in the vehicle width direction) and both
ends of the rotational axis 39a are rotatably held by bearing holes
(not shown) in the left and right side walls of the case 21. One
end of the rotational axis 39a protrudes outside the case 21 to be
coupled to a driving mechanism (not shown).
[0086] In FIG. 3, a position of the rear face door 39 indicated by
solid lines is a position mode where the rear face opening 35 is
fully opened. In contrast to this, a position of rear face door 39
indicated by chain double-dashed lines is a position where the rear
face opening 35 is fully closed.
[0087] In this example, electric actuators comprising servo motors
(not shown) are used as the driving mechanisms for rotating the air
mix door 27, the blowout mode switching door 38 and the rear face
door 39. Alternatively, as the driving mechanisms for these doors
27, 38 and 39, it may be possible to use manual operation
mechanisms for transferring manual operating force of operation
members (for example, manual operation levers) provided on the air
conditioner operation panel (not shown) via cables, link mechanisms
and the like.
[0088] Though not shown in the figures, the air conditioner
operation panel is provided in a dashboard disposed in a forward
region of the interior-cabin space 15 and has a refrigeration cycle
compressor operation switch and an air flow rate switch, as well as
a temperature setting switch, a blowout mode switching switch, a
front/rear air flow ratio adjustment switch, an inside air/outside
air mode switching switch and the like.
[0089] When the compressor operation switch on the air conditioner
operation panel is turned on, the electromagnetic clutch of the
refrigeration cycle compressor is energized and engaged and,
therefore, the compressor is driven by the engine. As a result, in
the cooling heat exchanger 24, the cold low-pressure refrigerant in
the refrigeration cycle absorbs heat from the air and evaporates so
as to cool the air.
[0090] Then, according to the temperature set by the temperature
setting switch, the air mix door 27 is operated to adjust the
temperature of the conditioned air flow.
[0091] Further, according to the setting of the blowout mode
switching switch, the blowout mode switching door 38 is operated to
switch the blowout mode, and according to the setting of the
front/rear air flow ratio adjustment switch, the rear face door 39
is operated to adjust the air flow ratio between the front face
blowout and the rear face blowout. Still further, according to the
setting of the inside air/outside air mode switching switch, the
outside air door and the inside air door are operated to switch the
inside air/outside air mode.
[0092] In this connection, on the rear wall section 21a of the case
21, a case side opening 40 that is provided facing the vehicle
rearward direction. This case side opening 40 is provided for
inspecting and cleaning the heat exchange core section 24a of the
cooling heat exchanger 24 and configured to be rectangular in this
example.
[0093] In this example, the cooling heat exchanger 24 is disposed
substantially vertically, and therefore, the heat exchange core
section 24a of the cooling heat exchanger 24 faces the case side
opening 40. More specifically, an air flow upstream portion of the
heat exchange core section 24a of the cooling heat exchanger 24
faces the case side opening 40.
[0094] The case side opening 40 can be opened and closed by a case
side cover 41. This case side cover 41 is molded of a resin
material that has elasticity to some extent and excellent strength,
such as polypropylene, similarly to the case 21.
[0095] The case side cover 41 is disposed outside the case 21 (in
the vehicle rearward direction) with respect to the case side
opening 40 and removably attached to the case 21 by fastening means
such as screws, clips and the like (not shown). The case side
opening 40 is opened and closed when the case side cover 41 is
attached and removed, respectively.
[0096] An area of the case side cover 41 is smaller than an opening
area of a cabin side opening 42 that is provided in the rear wall
section 12 of the cabin 10. This cabin side opening 42 is provided
facing the vehicle rearward direction, and at the same time, it
overlaps the case side opening 40. In this example, the cabin side
opening 42 is formed by rectangularly cutting out an outside sheet
of the vehicle (a steel sheet in this example) in the rear wall
section 12.
[0097] The cabin side opening 42 can be opened and closed by a
cabin side cover 43. Though this cabin side cover 43 is formed by
the steel sheet that is similar to the outside sheet of the
vehicle, it may be formed of a resin material and the like.
[0098] The cabin side cover 43 is disposed outside (rearward) the
cabin 10 with respect to the cabin side opening 42 and removably
attached to the rear wall section 12 of the cabin 10 by fastening
means such as screws, clips and the like (not shown). The cabin
side opening 42 is opened and closed when the cabin side cover 43
is attached and removed, respectively.
[0099] Next, in the above configuration, a procedure for inspecting
and cleaning the heat exchange core section 24a of the cooling heat
exchanger 24 will be described. First, the cabin side cover 43 is
removed from the rear wall section 12 of the cabin 10 to the
rearward of the cabin 10 to open the cabin side opening 42.
[0100] Since the cabin side cover 43 is disposed outside (rearward)
the cabin 10 with respect to the cabin side opening 42, the cabin
side cover 43 can be removed from the outside (rearward) of the
cabin 10.
[0101] Next, the case side cover 41 is removed from the case 21 to
the outside of the case (to the rearward of the vehicle) to open
the case side opening 40.
[0102] Since the case side opening 40 overlaps the cabin side
opening 42 and the case side cover 41 is disposed outside the case
21 (in the vehicle rearward direction) with respect to the case
side opening 40, the case side cover 41 can be removed from the
outside (rearward) of the cabin 10 through the cabin side opening
42.
[0103] Further, because the area of the case side cover 41 is
smaller than the opening area of the cabin side opening 42, the
removed case side cover 41 can be taken out to the outside of the
cabin 10 through the cabin side opening 42.
[0104] As described above, by opening the case side opening 40 and
the cabin side opening 42, the heat exchange core section 24a of
the cooling heat exchanger 24 is exposed to the outside of the
cabin 10 and, therefore, the heat exchange core section 24a of the
cooling heat exchanger 24 can be inspected and cleaned from the
outside of the cabin 10 (from the rearward of the cabin 10) through
the cabin side opening 42 and the case side opening 40.
[0105] Then, after the heat exchange core section 24a of the
cooling heat exchanger 24 is inspected and cleaned, the case side
cover 41 and the cabin side cover 43 are attached in the procedure
reverse to that for removal described above.
[0106] In a construction machine such as a hydraulic excavator,
which is used in a sandy and dusty environment etc., the heat
exchange core section 24a of the cooling heat exchanger 24 may
become clogged due to dust adhering to the clearance between the
fins of the core section. However, in this embodiment, the heat
exchange core section 24a of the cooling heat exchanger 24 can be
inspected and cleaned from the outside of the cabin 10 (from the
rearward of the cabin 10) while the cooling heat exchanger 24
remains accommodated in the case 21.
[0107] Therefore, in contrast to the vehicle air conditioner in
Japanese Unexamined Utility Model Publication No. H05-56516
mentioned above, when the cooling heat exchanger 24 is inspected
and cleaned, the cooling heat exchanger 24 does not have to be
taken out from the case 21 of the air conditioning unit 20 and it
does not have to be inspected and cleaned in the narrow cabin 10.
As a result, the cooling heat exchanger 24 can be inspected and
easily cleaned in a short period of time.
[0108] Further, in this embodiment, in which the air flow upstream
portion of the heat exchange core section 24a of the cooling heat
exchanger 24 is oriented toward the case side opening 40 and the
cabin side opening 42, the air flow upstream portion of the heat
exchange core section 24a that is more likely to be covered with
the dust can be inspected and easily cleaned in a short period of
time.
[0109] Still further, in this embodiment, as indicated by arrow a
in FIG. 3, the air passing through the cooling heat exchanger 24
flows from the vehicle rearward to the vehicle forward. On the
other hand, as indicated by arrow d in FIG. 3, the air passing
through the fool opening 37 also flows from the vehicle rearward to
the vehicle forward.
[0110] Thus, the flow direction of the air in the foot opening 37
coincides with that of the air passing through the cooling heat
exchanger 24. Therefore, the flow rate of the air passing through
the foot opening 37, and thus, the flow rate of the air blown out
from the foot blowout can be ensured easily.
[0111] Still further, in this embodiment, in which the air outlet
section 22e of the blower section 22 can be disposed at the
rearmost position of the air conditioning unit 20 as can be seen
from FIG. 2A, the air outlet section 22e of the blower section 22
can be kept far from the operator. Therefore, air blow noise heard
by the operator can be reduced.
[0112] Still further, in this embodiment, in which the
substantially rectangular-shaped cooling heat exchanger 24 is
disposed substantially vertically inside the case 21, the
dimensions of the air conditioning unit 20 in the front and rear
direction of the vehicle can be reduced. As a result, the space
available for the operator in the interior-cabin space 15 can be
extended.
[0113] As a reference example, the air conditioning unit 20 may be
configured reversely in the front and rear direction to that of
this embodiment, so that the case side opening 40 is opened toward
the seat 18 (in the vehicle forward direction). Alternatively, as
another reference example, the case side opening 40 may be formed
in the top surface section of the case 21 or, more specifically, in
a region above the inflow space 25 of the top surface section of
the case 21.
[0114] In these reference examples, though the cooling heat
exchanger 24 cannot be inspected and cleaned from the outside
(rearward) of the cabin 10 and it has to be inspected and cleaned
inside the cabin 10, the cabin side opening 42 and the cabin side
cover 43 can be omitted.
Second Embodiment
[0115] In contrast to the first embodiment described above, in
which the case side opening 40 is opened and closed by removing and
attaching the case side cover 41 from/to the case 21 and the cabin
side opening 42 is opened and closed by removing and attaching the
cabin side cover 43 from/to the rear wall section 12 of the cabin
10, in this second embodiment, as shown in FIG. 4, the both opening
40 and 42 are opened and closed by swinging the both covers 41 and
43 in a direction orthogonal to the opening direction of the
opening 40 and 42 (the front and rear direction of the vehicle in
this example).
[0116] More specifically, a top edge section of the case side cover
41 is secured to the case 21 via a hinge (not shown) and a top edge
section of the cabin side cover 43 is secured to the rear wall
section 12 of the cabin 10 via a hinge (not shown). Therefore, the
covers 41 and 43 are held swingably in the vertical direction, so
that the opening 40 and 42 can be easily opened and closed by the
covers 41 and 43.
[0117] Further, when the case side cover 41 is swung in the
direction to open the case side opening 40, the case side cover 41
protrudes to the outside of the cabin 10 through the cabin side
opening 42. Therefore, the case side opening 40 can be opened
completely.
[0118] In this connection, though the hinges disposed at the top
edge sections of the covers 41 and 43 in this example, the hinges
may be disposed at the bottom edge sections of the covers 41 and
43. Further alternatively, the hinges may be disposed at right or
left edge sections of the covers 41 and 43, so that the covers 41
and 43 can be held swingably in the horizontal direction.
Third Embodiment
[0119] In contrast to the second embodiment described above, in
which the opening 40 and 42 are opened by swinging the covers 41
and 43, in this third embodiment, as shown in FIG. 5, the both
opening 40 and 42 are opened and closed by shifting (sliding) the
covers 41 and 43 in a direction orthogonal to the opening direction
of the opening 40 and 42 (the front and rear direction of the
vehicle in this example).
[0120] More specifically, left and right edge sections of the case
side cover 41 are secured to the case 21 via slide mechanisms (not
shown) and the left and right edge sections of the cabin side cover
43 are secured to the rear wall section 12 via slide mechanisms
(not shown).
[0121] Therefore, the covers 41 and 43 are held slidably in the
vertical direction. Here, the lower part of the rear wall section
12 of the cabin 10 extends in the vertical direction and therefore,
the case side cover 41 can be shifted in the interior-cabin space
15 without interference with the rear wall section 12.
[0122] As described above, the opening 40 and 42 can be opened and
closed by sliding the covers 41 and 43 in the vertical
direction.
[0123] In this connection, though the covers 41 and 43 are held
slidably in the vertical direction, the covers 41 and 43 may be
held slidably in the horizontal direction.
Other Embodiments
[0124] Though the air conditioning unit 20 is disposed at the
rearmost and lowermost position of the interior-cabin space 15 in
the embodiments described above, the disposing position of the air
conditioning unit 20 is not limited to this position. For example,
the air conditioning unit 20 may be disposed at the lowermost
position in the center of the interior-cabin space 15 or, in other
words, under the seat 18.
[0125] In this case, the air conditioning unit 20 may be disposed
in an orientation horizontally rotated by 90 degrees from that in
the embodiments described above so that the heat exchange core
section 24a of the cooling heat exchanger 24 faces the side wall
section of the cabin 10, and the cabin side opening 42 and the
cabin side cover 43 may be disposed at the side wall section of the
cabin 10.
[0126] Further, though the cooling heat exchanger 24 and the
heating heat exchanger 26 are provided as heat exchangers for
exchanging heat with air in the embodiments described above, the
cooling heat exchanger 24 may be omitted and only the heating heat
exchanger 26 may be provided.
[0127] In this case, a heat exchange core section 24a of the
heating heat exchanger 26 may be disposed to face the case side
opening 40. As a result, the heating heat exchanger 26 can be
inspected and easily cleaned in a short period of time.
[0128] Still further, though the air flow upstream portion of the
heat exchange core section 24a of the cooling heat exchanger 24
faces the case side opening 40 in the embodiments described above,
an air flow downstream portion of the heat exchange core section
24a may face the case side opening 40.
[0129] Though the embodiments described above show examples in
which the vehicle air conditioner according to the present
invention is applied to the construction machine such as the
hydraulic excavator and the like, the present invention may be
applied not only to a construction machine such as a hydraulic
excavator and the like, but also to other various vehicles. For
example, the present invention may be applied to an agricultural
tractor, etc.
[0130] While the invention has been described with reference to
specific embodiments chosen for purposes of illustration, it should
be apparent that numerous modifications could be made thereto by
those skilled in the art without departing from the basic concept
and scope of the invention.
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