1
FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10, Rule 13]
OUTDOOR UNIT AND AIR CONDITIONER;
MITSUBISHI ELECTRIC CORPORATION, A CORPORATION ORGANISED
AND EXISTING UNDER THE LAWS OF JAPAN, WHOSE ADDRESS IS 7-3,
MARUNOUCHI 2-CHOME, CHIYODA-KU, TOKYO 1008310, JAPAN
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE
INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED
2
DESCRIPTION
Field
[0001] The present invention relates to an outdoor unit
including a compressor, a fan, and a control board, and an
5 air conditioner.
Background
[0002] Conventional air conditioners include an outdoor
unit that includes a compressor, a fan, a heat exchanger,
10 and a control board. The interior of the casing of the
outdoor unit is partitioned by a partition plate into a
blower room in which the fan is installed and a machine
room in which the compressor is installed. In the outdoor
unit disclosed in Patent Literature 1, the control board is
15 installed horizontally on the top of the partition plate.
The control board is installed across the blower room and
the machine room. In the machine room, the control board
is accommodated in an electric component box. A power
module is mounted on the control board. The electric
20 component box is provided with a cooler that dissipates
heat generated by the power module. The cooler is exposed
in the blower room. The cooler has a plurality of fins.
By the operation of the fan, air flowing in the blower room
is passed through the surfaces of the plurality of fins to
25 dissipate heat via the plurality of fins.
Citation List
Patent Literature
[0003] Patent Literature 1: Japanese Patent Application
30 Laid-open No. 2011-7363
Summary
3
Technical Problem
[0004] However, in the outdoor unit described in Patent
Literature 1, the flow of air in the blower room and the
orientation of the fins of the cooler are not optimized,
5 and heat generated by the power module may not be able to
be sufficiently dissipated. This poses the problem that it
is necessary to increase the size of the cooler, or to
reduce the operating capacity of the air conditioner to
reduce the generation of heat from the power module.
10 [0005] The present invention has been made in view of
the above, and an object thereof is to provide an outdoor
unit that allows an improvement in the efficiency of heat
dissipation from a cooler to prevent a reduction in the
operating capacity of an air conditioner.
15
Solution to Problem
[0006] To solve the aforementioned problems and achieve
the object, an outdoor unit according to the present
invention includes a casing with an inlet formed in a back
20 surface and an outlet formed in a front surface, a fan
accommodated in the casing to draw in air from the inlet
and blow out the air from the outlet, a compressor
accommodated in the casing to compress a refrigerant, a
heat exchanger accommodated in the casing to cause heat
25 exchange between the refrigerant and the air, a partition
plate partitioning an interior of the casing into a machine
room in which the compressor is installed and a blower room
in which the fan is installed, a control board installed
horizontally on a top of the partition plate across the
30 machine room and the blower room, an electric component box
covering the control board, a heat-generating component
installed on the blower room side of the control board to
drive the compressor and the fan, and a cooler connected
4
to the heat-generating component and including a plurality
of fins exposed from the electric component box. The
plurality of fins has main surfaces facing the front
surface, and the lowest fin of the fins on the back surface
5 side of a center of the cooler as viewed from the front
surface is higher than the highest fin of the fins on the
front surface side of the center of the cooler as viewed
from the front surface.
10 Advantageous Effects of Invention
[0007] The present invention achieves an effect of being
able to provide an outdoor unit that allows an improvement
in the efficiency of heat dissipation from a cooler to
prevent a reduction in the operating capacity of an air
15 conditioner.
Brief Description of Drawings
[0008] FIG. 1 is a diagram illustrating a configuration
of an air conditioner according to a first embodiment.
20 FIG. 2 is a diagram illustrating a configuration
example of a control board and an electric component box
according to the first embodiment.
FIG. 3 is a bottom view of the control board and the
electric component box according to the first embodiment as
25 viewed from the underside of an outdoor unit.
FIG. 4 is a front view of the control board and the
electric component box according to the first embodiment.
FIG. 5 is a right-side view of the control board and
the electric component box according to the first
30 embodiment.
FIG. 6 is an opened-up view of the outdoor unit
according to the first embodiment as viewed from above.
FIG. 7 is an opened-up view of the outdoor unit
5
according to the first embodiment as viewed from the side.
FIG. 8 is a first diagram illustrating the shape of a
cooler according to a second embodiment.
FIG. 9 is a second diagram illustrating the shape of a
5 cooler according to the second embodiment.
FIG. 10 is a third diagram illustrating the shape of a
cooler according to the second embodiment.
FIG. 11 is a fourth diagram illustrating the shape of
a cooler according to the second embodiment.
10
Description of Embodiments
[0009] Hereinafter, an outdoor unit and an air
conditioner according to embodiments of the present
invention will be described in detail with reference to the
15 drawings. Note that the embodiments are not intended to
limit this invention.
[0010] First Embodiment.
FIG. 1 is a diagram illustrating a configuration of an
air conditioner according to a first embodiment. An air
20 conditioner 100 has an indoor unit 1 and an outdoor unit 2.
The indoor unit 1 and the outdoor unit 2 are connected via
a gas connecting pipe 3a and a liquid connecting pipe 3b.
The gas connecting pipe 3a and the liquid connecting pipe
3b are also collectively referred to as refrigerant piping
25 3. The refrigerant piping 3 is filled with a refrigerant,
which circulates between the indoor unit 1 and the outdoor
unit 2 through the refrigerant piping 3, so that the air
conditioner 100 exchanges heat between the inside and the
outside of a room.
30 [0011] The outdoor unit 2 includes a casing 20, a
compressor 4, an expansion valve 5, a four-way valve 6, a
heat exchanger 7, a fan 8, a control board 9, an electric
component box 10, and a partition plate 11. The casing 20
6
accommodates the compressor 4, the expansion valve 5, the
four-way valve 6, the heat exchanger 7, the fan 8, the
control board 9, the electric component box 10, and the
partition plate 11 inside. The casing 20 has a back
5 surface 211 in which an inlet 201 is formed, and a front
surface 222 in which a bell mouth 202, which is an outlet,
is formed. The refrigerant piping 3 is connected to the
side surface 221 side of the casing 20.
[0012] The refrigerant circulates through the
10 refrigerant piping 3, the compressor 4, the expansion valve
5, the four-way valve 6, the heat exchanger 7, and a heat
exchanger included in the indoor unit 1, forming a
refrigeration cycle. The heat exchanger 7 covers the back
surface 211. The compressor 4 compresses the refrigerant.
15 The heat exchanger 7 causes heat exchange between the
refrigerant and air. The fan 8 rotates, drawing air in
from the inlet 201 and blowing it out from the bell mouth
202. The air drawn in from the inlet 201 passes through
the heat exchanger 7. When the air passes through the heat
20 exchanger 7, heat exchange is performed between the air and
the heat exchanger 7. The control board 9 includes a
control unit that controls the compressor 4, the expansion
valve 5, the four-way valve 6, and the fan 8. The
partition plate 11 partitions the interior of the casing 20
25 into a blower room 50 in which the heat exchanger 7 and the
fan 8 are installed, and a machine room 51 in which the
compressor 4, the expansion valve 5, and the four-way valve
6 are installed. The control board 9 is horizontally fixed
on the top of the partition plate 11 across the machine
30 room 51 and the blower room 50. The electric component box
10 covers the control board 9.
[0013] FIG. 2 is a diagram illustrating a configuration
example of the control board 9 and the electric component
7
box 10 according to the first embodiment. A first power
module 13 that drives the compressor 4 and the fan 8 and
two electronic components 17 are mounted on the control
board 9. In the present embodiment, the first power module
5 13 is mounted on the control board 9, but other than the
first power module 13, a heat-generating component that
generates heat may be mounted. The heat-generating
component includes a first power module. The first power
module 13 is mounted on the blower room 50 side of the
10 control board 9, and is exposed from the electric component
box 10. The electronic components 17 are electrolytic
capacitors or the like. The electronic components 17 are
mounted on the machine room 51 side of the control board 9
and are placed away from a cooler 14. The cooler 14 is
15 connected to the first power module 13. The cooler 14 has
a plurality of fins 141 to dissipate heat generated by the
first power module 13. The cooler 14 is exposed from the
electric component box 10. When the plurality of fins 141
is viewed from the front surface 222 of the outdoor unit 2,
20 main surfaces of the fins 141 that are surfaces with large
areas face the front surface 222. When viewed from the
front surface 222 of the outdoor unit 2, the lowest fin of
the fins 141 on the back surface 211 side of the center of
the cooler 14 is higher than the highest fin of those on
25 the front surface 222 side of the center of the cooler 14.
The electronic components 17 are higher than the lowest fin
141 of the plurality of fins 141.
[0014] The electric component box 10 includes a housing
chamber 110 in which the electronic components 17 are
30 housed. Of the surfaces constituting the housing chamber
110, a separation surface 15 facing the machine room 51
side approaches the side surface 221 of the casing 20 on
the machine room 51 side as it gets closer to the back
8
surface 211. Like the separation surface 15, the partition
plate 11 also approaches the side surface 221 of the casing
20 on the machine room 51 side as it gets closer to the
back surface 211. The separation surface 15 is a portion
5 indicated by oblique lines in FIG. 2.
[0015] FIG. 3 is a bottom view of the control board 9
and the electric component box 10 according to the first
embodiment as viewed from the underside of the outdoor unit
2. FIG. 4 is a front view of the control board 9 and the
10 electric component box 10 according to the first embodiment.
FIG. 5 is a right-side view of the control board 9 and the
electric component box 10 according to the first embodiment.
As illustrated in FIGS. 3 to 5, the separation surface 15
constituting the electric component box 10 creates a space
15 between the electric component box 10 and the cooler 14.
The electronic components 17 included in the electric
component box 10 cannot be installed in the space between
the electric component box 10 and the cooler 14, and thus
are installed away from the cooler 14. The separation
20 surface 15 allows a current of air between the separation
surface 15 and the cooler 14 to flow easily.
[0016] FIG. 6 is an opened-up view of the outdoor unit 2
according to the first embodiment as viewed from above.
Currents of air traveling from the back surface 211 side to
25 the front surface 222 side as viewed from the front of the
outdoor unit 2 are indicated by arrows. In the first
embodiment, a cross section of the separation surface 15
cut in a horizontal plane is curved in an arc. This
configuration allows currents of air drawn in from the back
30 surface 211 to be less obstructed by the partition plate 11
and the separation surface 15 on the back surface 211 side
of the machine room 51. Consequently, more air can be
passed through the heat exchanger 7 to improve the
9
efficiency of heat exchange. Since the cross section of
the separation surface 15 is bent in an arc, the area of
the undersurface of the electric component box 10 is
reduced. Therefore, a space is created between the
5 electric component box 10 and the cooler 14 as compared
with the case where the cross section of the separation
surface is L-shaped. The separation surface 15 forms an
arc similar to that of the partition plate 11.
Consequently, more air can be passed between the plurality
10 of fins 141.
[0017] A current of air striking the cooler 14 will be
described. Air in the center of fan 8 rapidly flows
straight from the back surface 211 toward the front surface
222. Air in portions away from the center of the fan 8
15 rapidly flows obliquely toward the bell mouth 202 in the
front surface 222. Thus, a current of air easily flows
between the separation surface 15 and the cooler 14,
cooling the cooler 14. By the way, the cross section of a
separation surface of an electric component box of a
20 conventional outdoor unit which separates a housing chamber
in which electronic components are housed from a blower
room is L-shaped. Consequently, the separation surface of
the conventional electric component box obstructs a current
of air passing through obliquely, so that only part of the
25 current of air strikes. Since the plurality of fins 141 is
formed with the main surfaces facing the front surface 222,
the direction of air flow paths formed between the
plurality of fins 141 is nearly parallel to the direction
of air flowing obliquely as described above. Consequently,
30 air smoothly flows into the flow paths between the
plurality of fins 141. This allows an increase in air
passing through the flow paths between the plurality of
fins 141.
10
[0018] FIG. 7 is an opened-up view of the outdoor unit 2
according to the first embodiment as viewed from the side.
Currents of air traveling from the back surface 211 to the
front surface 222 as viewed from the front of the outdoor
5 unit 2 are indicated by arrows. Air flowing to the center
of the fan 8 flows straight, while air flowing from an
upper part and a lower part of the outdoor unit 2 flows
toward the bell mouth 202 in the front surface 222.
Although not indicated by arrows, air in a direction not
10 described above, for example, air striking the front
surface 222 once and bouncing back also flows in the
outdoor unit 2. However, the velocity of the air bouncing
back from the front surface 222 is slower than that of the
air flowing to the center of the fan 8, and its flow rate
15 is smaller, and thus its effect of cooling the cooler 14 is
small. By the way, the respective heights of a plurality
of fins of a cooler of a conventional air conditioner are
the same. Thus, fins are also formed at a portion on the
front surface side where the flow velocity is slow, and the
20 material of the fins at the portion on the front surface
side is wasted.
[0019] As described above, in the first embodiment, the
cooler 14 has the plurality of fins 141. When the
plurality of fins 141 is viewed from the front surface 222
25 of the outdoor unit 2, the main surfaces of the fins 141
with large areas face the front surface 222 side. The fins
141 on the back surface 211 side of the outdoor unit 2 are
higher, and the fins 141 on the front surface 222 side are
lower. Consequently, air flows efficiently through the
30 fins 141. Therefore, the cooler 14 can be reduced in the
size of the fins 141 as compared with conventional coolers.
Further, the outdoor unit 2 can be reduced in weight and
cost. Furthermore, since the separation surface 15 is
11
shaped in an arc so that a space is formed between the
separation surface 15 and the cooler 14, and the electronic
components 17 are mounted at positions away from the cooler
14, a current of air easily strikes the fins 141 of the
5 cooler 14. Moreover, the fins 141 that are struck by much
air flowing through the outdoor unit 2 are made higher than
the fins 141 that are not struck by much air. This allows
an improvement in the efficiency of cooling the first power
module 13 by the cooler 14. Consequently, there is no need
10 to reduce the operating capacity of the air conditioner 100
to reduce the heat generation of the first power module 13.
Further, the weight of the outdoor unit 2 can be reduced,
and the cost of the outdoor unit 2 can be reduced. That is,
it is possible to prevent an increase in the manufacturing
15 cost of the outdoor unit 2. Furthermore, with the same
weight and cost as those of conventional coolers, the
cooler may be enhanced in cooling capacity compared to the
conventional coolers. This can improve the operating
capacity of the air conditioner 100 compared to that of
20 conventional ones.
[0020] Furthermore, even if the shape of the fins 141 is
the same as that of conventional ones, only by the
separation surface 15 shaped in an arc so that a space is
formed between the separation surface 15 and the cooler 14,
25 the effect of being able to cool the fins 141 of the cooler
14 more than before can be provided. Furthermore, even if
the shape of the separation surface 15 is the same as that
of a conventional one, only by the fins 141 of the cooler
14 with the fins 141 on the back surface 211 side of the
30 outdoor unit 2 being higher and the fins 141 on the front
surface 222 side being lower, the effect of being able to
make the cooler smaller, lighter, and lower in cost than
before can be provided.
12
[0021] Second Embodiment.
FIG. 8 is a first diagram illustrating the shape of a
cooler according to a second embodiment. A cooler 14a is
provided in the outdoor unit 2 as in the first embodiment.
5 In the present embodiment, the same reference numerals as
those of the first embodiment are assigned to components
having the same functions as those of the first embodiment
to avoid redundant description. In the present embodiment,
the cooler 14a is connected to a second power module 16.
10 The second power module 16 is disposed on the same plane as
the first power module 13. The second power module 16 has
a smaller power loss than the first power module 13. Thus,
the second power module 16 generates less heat than the
first power module 13. The second power module 16 is
15 disposed on the front surface 222 side of the center of the
cooler 14a as viewed from the front of the outdoor unit 2.
The first power module 13 is disposed on the back surface
211 side of the center of the cooler 14a as viewed from the
front of the outdoor unit 2. The second power module 16 is
20 included in the heat-generating component.
[0022] The cooler 14a has the fins 141 placed only
directly below portions where the first power module 13 and
the second power module 16 are mounted, and eliminates the
fins 141 at portions where the first power module 13 and
25 the second power module 16 are not mounted. Most of the
heat generated by the first power module 13 and the second
power module 16 is transferred to the fins 141 of the
cooler 14 located directly below to be cooled. This
prevents the generated heat from being transferred to the
30 fins 141 far from the first power module 13 and the second
power module 16. Therefore, even if the fins 141 are
provided at portions far from the first power module 13 and
the second power module 16, their effect of cooling them is
13
small. The fins 141 of the cooler 14a are increased in
height from the fin 141 closest to the front surface 222
toward the fin 141 closest to the back surface 211. The
cooler 14a, which eliminates the fins 141 at the portions
5 where the first power module 13 and the second power module
16 are not located, is manufactured with less aluminum
material. Thus, the cooler 14a is reduced in weight and
cost. Conventional coolers have many fins 141 placed in a
portion where a power module is not disposed, and thus have
10 a poor efficiency of cooling of the power module.
[0023] On the cooler 14a, the first power module 13 that
generates more heat than the second power module 16 is
disposed on the back surface 211 side of the outdoor unit 2
as described in the first embodiment, and the second power
15 module 16 is disposed on the front surface 222 side. By
thus disposing a power module that generates more heat in a
position where it is cooled more easily, it can be
prevented to mount a fan for cooling the power module that
generates more heat, so that the size of the cooler 14a can
20 be reduced.
[0024] As described above, in the present embodiment,
the fins 141 are placed directly below the first power
module 13 and the second power module 16 to eliminate the
fins 141 at the portions where the first power module 13
25 and the second power module 16 are not located. This can
prevent the cooler 14a from deteriorating in the function
of cooling the first power module 13 and the second power
module 16, and can prevent a decrease in the operating
capacity of the air conditioner 100. Further, the cooler
30 14a is reduced in size, weight, and cost.
[0025] FIG. 9 is a second diagram illustrating the shape
of a cooler according to the second embodiment. Like the
cooler 14a, a cooler 14b has the fins 141 placed only
14
directly below the portions where the first power module 13
and the second power module 16 are mounted. However, the
respective heights of the plurality of fins 141 placed
directly below the first power module 13 are the same.
5 Also, the respective heights of the plurality of fins 141
placed directly below the second power module 16 are the
same. The plurality of fins 141 of the cooler 14b placed
directly below the first power module 13 is higher than the
plurality of fins 141 placed directly below the second
10 power module 16. On the other hand, for the cooler 14a,
the heights of the fins 141 are increased from the first
power module 13 toward the second power module 16.
[0026] FIG. 10 is a third diagram illustrating the shape
of a cooler according to the second embodiment. Like the
15 cooler 14b, a cooler 14c has the fins 141 placed only
directly below the portions where the first power module 13
and the second power module 16 are mounted. However, the
respective heights of the plurality of fins 141 placed
directly below the first power module 13 are different.
20 Also, the respective heights of the plurality of fins 141
of the cooler 14c placed directly below the second power
module 16 are different. As viewed from the front of the
outdoor unit 2, the average height of the fins 141 on the
back surface 211 side of the center of the cooler 14c is
25 higher than the average height of the fins 141 on the front
surface 222 side of the center of the cooler 14c.
[0027] FIG. 11 is a fourth diagram illustrating the
shape of a cooler according to the second embodiment. A
cooler 14d has the fins 141 on the back surface 211 side
30 made higher and the fins 141 on the front surface 222 side
lower as viewed from the front of the outdoor unit 2, and
the fins 141 at the portions not directly below the first
power module 13 and the second power module 16 formed by
15
the fins 141 that are lower than any one of the fins 141
directly below the first power module 13 and the second
power module 16.
[0028] Like the coolers 14b to 14d, even when the
5 heights of the fins 141 are different from the heights of
those of the cooler 14a, the same effect as that of the
cooler 14a can be obtained.
[0029] The configurations described in the above
embodiments illustrate an example of the subject matter of
10 the present invention, and can be combined with another
known art, and can be partly omitted or changed without
departing from the scope of the present invention.
Reference Signs List
15 [0030] 1 indoor unit; 2 outdoor unit; 3 refrigerant
piping; 3a gas connecting pipe; 3b liquid connecting
pipe; 4 compressor; 5 expansion valve; 6 four-way valve;
7 heat exchanger; 8 fan; 9 control board; 10 electric
component box; 11 partition plate; 13 first power module;
20 14, 14a, 14b, 14c, 14d cooler; 15 separation surface; 16
second power module; 17 electronic component; 20 casing;
50 blower room; 51 machine room; 100 air conditioner; 110
housing chamber; 141 fin; 201 inlet; 202 bell mouth; 211
back surface; 221 side surface; 222 front surface.
25
16
We Claim:
1. An outdoor unit comprising:
5 a casing with an inlet formed in a back surface and an
outlet formed in a front surface;
a fan accommodated in the casing to draw in air from
the inlet and blow out the air from the outlet;
a compressor accommodated in the casing to compress a
10 refrigerant;
a heat exchanger accommodated in the casing to cause
heat exchange between the refrigerant and the air;
a partition plate partitioning an interior of the
casing into a machine room in which the compressor is
15 installed and a blower room in which the fan is installed;
a control board installed horizontally on a top of the
partition plate across the machine room and the blower
room;
an electric component box covering the control board;
20 a heat-generating component installed on the blower
room side of the control board to drive the compressor and
the fan; and
a cooler connected to the heat-generating component
and including a plurality of fins exposed from the electric
25 component box,
the plurality of fins having
main surfaces facing the front surface, the lowest fin
of the fins on the back surface side of a center of the
cooler as viewed from the front surface being higher than
30 the highest fin of the fins on the front surface side of
the center of the cooler as viewed from the front surface.
2. The outdoor unit according to claim 1, further
17
comprising:
an electronic component installed on the machine room
side of the control board and higher than the lowest fin of
the plurality of fins, wherein
5 the electric component box includes
a housing chamber housing the electronic component,
the housing chamber is formed by surfaces including a
separation surface facing the machine room side, and
the separation surface approaches a side surface of
10 the casing on the machine room side as the separation
surface gets closer to the back surface.
3. The outdoor unit according to claim 1 or 2, wherein an
average height of the fins on the back surface side of the
15 center is higher than an average height of the fins on the
front surface side of the center.
4. The outdoor unit according to any one of claims 1 to 3,
wherein
20 the plurality of fins is
increased in height from the fin closest to the front
surface toward the fin closest to the back surface.
5. The outdoor unit according to any one of claims 1 to 4,
25 wherein
the heat-generating component includes
a first power module and a second power module having
a smaller power loss than the first power module,
the cooler
30 connects the first power module and the second power
module,
the plurality of fins is
placed directly below the first power module and the
18
second power module,
the first power module is
installed on the back surface side of the center, and
the second power module is
5 installed on the front surface side of the center.
6. The outdoor unit according to claim 5, wherein
the fins at a portion not directly below the first
power module and the second power module are
10 lower than any one of the fins installed directly
below the first power module and the second power module.
7. An air conditioner comprising:
the outdoor unit according to any one of claims 1 to
15 6; and
an indoor unit connected to the outdoor unit via
refrigerant piping.