U.S. patent application number 14/348361 was filed with the patent office on 2014-09-18 for outdoor unit for air conditioning device.
This patent application is currently assigned to DAIKIN INDUSTRIES, LTD.. The applicant listed for this patent is DAIKIN INDUSTRIES, LTD.. Invention is credited to Tadafumi Nishimura, Mamoru Okumoto, Yutaka Shibata, Hiroshi You.
Application Number | 20140263765 14/348361 |
Document ID | / |
Family ID | 47994765 |
Filed Date | 2014-09-18 |
United States Patent
Application |
20140263765 |
Kind Code |
A1 |
You; Hiroshi ; et
al. |
September 18, 2014 |
OUTDOOR UNIT FOR AIR CONDITIONING DEVICE
Abstract
A spray nozzle of an outdoor unit is provided with: an air guide
portion through which air flows; a water guide portion through
which water flows and which causes the air flowing through the air
guide portion to flow into water to form water containing a large
number of bubbles; and a spray portion that is located downstream
of the water guide portion in a direction of water flow and sprays,
to the outside, the water containing a large number of bubbles
which is formed in the water guide portion.
Inventors: |
You; Hiroshi; (Sakai-shi,
JP) ; Nishimura; Tadafumi; (Sakai-shi, JP) ;
Okumoto; Mamoru; (Sakai-shi, JP) ; Shibata;
Yutaka; (Sakai-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DAIKIN INDUSTRIES, LTD. |
Osaka-shi, Osaka |
|
JP |
|
|
Assignee: |
DAIKIN INDUSTRIES, LTD.
Osaka-shi, Osaka
JP
|
Family ID: |
47994765 |
Appl. No.: |
14/348361 |
Filed: |
September 27, 2012 |
PCT Filed: |
September 27, 2012 |
PCT NO: |
PCT/JP2012/006183 |
371 Date: |
March 28, 2014 |
Current U.S.
Class: |
239/690 ;
62/314 |
Current CPC
Class: |
F25B 2339/041 20130101;
B05B 7/0483 20130101; F24F 5/0035 20130101; B05B 7/0491 20130101;
F24F 1/42 20130101; B05B 7/0458 20130101; B05B 12/12 20130101; F24F
2013/225 20130101; F28C 3/08 20130101 |
Class at
Publication: |
239/690 ;
62/314 |
International
Class: |
F28C 3/08 20060101
F28C003/08 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 30, 2011 |
JP |
20111-217974 |
Sep 7, 2012 |
JP |
2012-197301 |
Claims
1. An outdoor unit for an air conditioning device, comprising: a
heat exchanger; and a spray nozzle for spraying water to air
flowing toward the heat exchanger, wherein the spray nozzle has: an
air guide portion through which air flows; a water guide portion
through which water flows and which causes the air flowing through
the air guide portion to flow into water to form water containing a
large number of bubbles; and a spray portion that is located
downstream of the water guide portion in a direction of water flow
and sprays, to the outside, the water containing a large number of
bubbles which is formed in the water guide portion.
2. The outdoor unit for an air conditioning device according to
claim 1, wherein the water guide portion has a pipe wall shaped
into a pipe and also has one or a plurality of air introduction
holes penetrating the pipe wall in a thickness direction, and the
air guide portion is shaped into a pipe so as to surround an outer
circumference of the water guide portion.
3. The outdoor unit for an air conditioning device according to
claim 2, wherein the water guide portion has the plurality of air
introduction holes, and the plurality of air introduction holes are
provided at intervals in a circumferential direction of the water
guide portion and a direction in which the water guide portion
extends.
4. The outdoor unit for an air conditioning device according to
claim 1, wherein the water guide portion is shaped into a pipe and
has, at least partially, a porous portion, and the air guide
portion is shaped into a pipe so as to surround an outer
circumference of the water guide portion.
5. The outdoor unit for an air conditioning device according to
claim 4, wherein the porous portion is formed from foam metal.
6. The outdoor unit for an air conditioning device according to
claim 1, wherein the water guide portion is shaped into a pipe, and
the air guide portion is shaped into a pipe and has a leading end
portion thereof connected to the water guide portion.
7. The outdoor unit for an air conditioning device according to
claim 6, wherein the air guide portion has a porous portion at a
leading end portion thereof.
8. The outdoor unit for an air conditioning device according to
claim 1, further comprising: a charger that electrically charges
water sprayed from the spray nozzle.
9. The outdoor unit for an air conditioning device according to
claim 1, wherein the water guide portion vertically guides water
containing bubbles.
10. The outdoor unit for an air conditioning device according to
claim 9, wherein the spray nozzle is disposed outside the heat
exchanger in the outdoor unit, the water guide portion guides water
containing bubbles downward, and the spray portion is disposed on a
lower side of the water guide portion and sprays, downward, the
water containing a large number of bubbles which is guided by the
water guide portion.
11. The outdoor unit for an air conditioning device according to
claim 9, further comprising: a fan that forms flow of air directed
toward the heat exchanger, wherein the fan is disposed above and
inward of the heat exchanger in the outdoor unit and discharges
upward, to the outside of the outdoor unit, air that has flowed
into the outdoor unit and been subjected to heat exchange by the
heat exchanger, the spray nozzle is disposed further toward an
outer side than the heat exchanger in the outdoor unit, the water
guide portion guides water containing bubbles upward, and the spray
portion is disposed on an upper side of the water guide portion and
sprays upward the water containing a large number of bubbles which
is guided by the water guide portion.
Description
TECHNICAL FIELD
[0001] The present invention relates to an outdoor unit for an air
conditioning device.
BACKGROUND ART
[0002] There has conventionally been known an outdoor unit for an
air conditioning device that has a spray device for auxiliary
cooling a heat exchanger by spraying water from a spray nozzle to
the heat exchanger. Cooling the heat exchanger by means of the
sprayed water in this outdoor unit can effectively reduce the power
(power consumption) required by the air conditioning device. In
this type of air conditioning device, unfortunately, droplets of
the water adhering to the surface of the heat exchanger often leads
to corrosion of the heat exchanger.
[0003] Patent Document 1 discloses an outdoor unit provided with a
fine mist generating nozzle. This fine mist generating nozzle is
located on the upstream side of a heat exchanger and away
therefrom, and generates fine mist having a particle diameter of 10
.mu.m or less by injecting air and water simultaneously. Patent
Document 1 describes that the fine mist injected from the fine mist
generating nozzle evaporates prior to reaching the heat exchanger,
preventing adherence of the droplets to the heat exchanger. [0004]
Patent Document 1: Japanese Patent Application Publication No.
2008-128500
[0005] However, a spray nozzle that injects air and water
simultaneously from its spray hole is a conventional two-fluid
nozzle that creates fine droplets by adding shear force to the
water at the pressure of the air. For this reason, the spray nozzle
requires large power for the purpose of injecting air at high
speeds. In such a case, the power reduction effect of the entire
air conditioning device might not be accomplished adequately.
SUMMARY OF THE INVENTION
[0006] An object of the present invention is to provide an outdoor
unit that is capable of reducing the power of the entire air
conditioning device while preventing corrosion of a heat
exchanger.
[0007] An outdoor unit for an air conditioning device according to
the present invention has a heat exchanger and a spray nozzle for
spraying water to air flowing toward the heat exchanger. The spray
nozzle is provided with an air guide portion through which the air
flows, a water guide portion through which water flows and in which
the air flowing through the air guide portion flows into the water
to form water which contains a large number of bubbles, and a spray
portion which is located downstream of the water guide portion in a
direction of water flow and which sprays to the outside the water
formed in the water guide portion and containing a large number of
bubbles.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a schematic diagram showing an outdoor unit
according to a first embodiment of the present invention.
[0009] FIG. 2 is a perspective view showing how a heat exchanger
and spray nozzles are arranged in the outdoor unit.
[0010] FIG. 3 is a cross-sectional diagram of one of the spray
nozzles.
[0011] FIG. 4 is a cross-sectional diagram of a spray nozzle of an
outdoor unit according to a second embodiment of the present
invention.
[0012] FIG. 5 is a cross-sectional diagram of a spray nozzle of an
outdoor unit according to a third embodiment of the present
invention.
[0013] FIG. 6A is a perspective view showing an air guide pipe of
the spray nozzle according to the third embodiment, FIG. 6B a
perspective view showing modification 1 of the air guide pipe, and
FIG. 6C a perspective view showing modification 2 of the air guide
pipe.
[0014] FIG. 7 is a schematic diagram showing an outdoor unit
according to another embodiment of the present invention.
[0015] FIG. 8 is a perspective view showing how a heat exchanger
and spray nozzles are arranged in the outdoor unit.
[0016] FIG. 9 is a schematic diagram for explaining an example of
the arrangement of spray nozzles in relation to the heat
exchanger.
[0017] FIG. 10 is a schematic diagram showing an outdoor unit
according to yet another embodiment of the present invention.
[0018] FIG. 11 is a diagram for explaining the relationship between
a distribution of wind velocity of air flowing toward a heat
exchanger in the outdoor unit and the distance between a spray
nozzle and each of various sections of the heat exchanger.
[0019] FIG. 12A is a schematic diagram for explaining modification
1 of a charging mechanism, and FIG. 12B an enlarged perspective
view for explaining a spray nozzle and an induction electrode.
[0020] FIG. 13 is a schematic diagram for explaining modification 2
of the charging mechanism.
BEST MODE FOR CARRYING OUT THE INVENTION
First Embodiment
[0021] An outdoor unit according to a first embodiment of the
present invention is now described hereinafter with reference to
the drawings.
[0022] An outdoor unit 11 according to the first embodiment is used
in an air conditioning device. The air conditioning device has the
outdoor unit 11 shown in FIG. 1, an indoor unit which is not shown,
and a refrigerant pipe section, not shown, which connects the
outdoor unit 11 and the indoor unit to each other. As shown in FIG.
1, the outdoor unit 11 has a case 12, a heat exchanger 13, a fan
14, a compressor 15, a spray device 20, an outside air temperature
sensor 18, a controller 16 and the like. The heat exchanger 13, the
fan 14, the compressor 15, and the controller 16 are disposed
inside the case 12. The fan 14, the compressor 15, and the spray
device 20 are controlled by the controller 16. The compressor 15
and the heat exchanger 13 are provided in a refrigerant circuit of
the air conditioning device.
[0023] Examples of the heat exchanger 13 include, but are not
limited to, a cross fin coil-type heat exchanger. The cross fin
coil-type heat exchanger has heat-transfer pipes and a large number
of plate fins through which the heat-transfer pipes penetrate. A
refrigerant flows inside the heat-transfer pipes, and outside air
flows between the plate fins. As a result, heat exchange between
the refrigerant and the outside air takes place.
[0024] As shown in FIG. 2, the heat exchanger 13 extends upward
from a bottom panel of the case 12 and formed in substantially a
U-shape as planarly viewed. In other words, the heat exchanger 13
is provided upright with respect to an installation surface
(horizontal surface) of the outdoor unit 11. Of the four side
panels of the case 12, the three side panels facing the heat
exchanger 13 are each provided with an air inlet, not shown, which
draws in outside air into the case 12. The top panel of the case 12
is provided with an air outlet 17 for blowing the air of the case
12 to the outside.
[0025] A centrifugal fan, an axial fan, a diagonal flow fan or the
like can be used as the fan 14. The fan 14 has an impeller 14a and
a motor, not shown, which rotates the impeller 14a. The fan 14 is
disposed inward of the heat exchanger 13 in a horizontal direction
in the outdoor unit 11 and above the heat exchanger 13. More
specifically, the fan 14 is provided in an upper part of the case
12, as shown in FIG. 1, and is disposed immediately below the air
outlet 17 shown in FIG. 2. The fan 14 emits upward, from the
outdoor unit 11 (the case 12) to the outside, air that flew into
the outdoor unit 11 (the case 12) and was subjected to heat
exchange by the heat exchanger 13. In other words, the fan 14 is
located downstream of the heat exchanger 13 in a direction of
airflow.
[0026] When the air conditioning device is running, the compressor
15 receives power, which consequently allows the refrigerant to
circulate in the refrigerant circuit between the outdoor unit 11
and the indoor unit, and at the same time power is applied to the
motor of the fan 14 to rotate the impeller 14a, thereby drawing in
outside air through the air inlet into the case 12. Subsequent to
heat exchange between the outside air drawn into the case 12 and
the refrigerant in the heat exchanger 13 as described above, the
outside air is blown to the outside of the case 12 via the air
outlet 17. More specifically, during, for example, a cooling
operation of the air conditioning device, heat exchange takes place
between the outside air drawn into the case 12 and the
high-temperature, high-pressure refrigerant via the heat-transfer
pipe of the heat exchanger 13 functioning as a condenser, the
refrigerant flowing through the heat-transfer pipe. In other words,
the outside air cools the heat-transfer pipe of the heat exchanger
13 and the refrigerant. As a result, the refrigerant flowing
through the heat-transfer pipe is cooled and condensed.
[0027] The spray device 20 is described next. The spray device 20
is capable of cooling the outside air flowing toward the heat
exchanger 13 during the cooling operation. In other words, the
spray device 20 lowers the temperature of the outside air flowing
toward the heat exchanger 13. In this manner, the effect of cooling
the heat-transfer pipe of the heat exchanger 13 and the refrigerant
can be enhanced. The spray device 20 can therefore improve the
cooling performance of the air conditioning device by auxiliary
cooling the heat exchanger 13 and the refrigerant.
[0028] As shown in FIGS. 1 to 3, the spray device 20 has a
plurality of spray nozzles 21, a water supply mechanism 60, an air
supply mechanism 70, and a charging mechanism 80 as a charger.
[0029] The plurality of spray nozzles 21 are each supported by a
supporting member, not shown, which is provided separately on each
side panel of the case 12 or in the case 12. Each of the spray
nozzles 21 is located upstream of the heat exchanger 13 in a
direction of an air stream which is formed as the impeller 14a of
the fan 14 rotates. In the present embodiment, each of the spray
nozzles 21 is disposed on the outside of and above the heat
exchanger 13 in the outdoor unit 11, in such a manner as to spray
droplets (water drops, in the present embodiment) downward. In
other words, each of the spray nozzles 21 is disposed such that an
axial direction thereof is substantially perpendicular to the
direction of outside air (the air) flowing substantially
horizontally toward the heat exchanger 13. Water drops that are
sprayed from each of the spray nozzles 21 are spread radially
downward and moved toward the heat exchanger 13 by the flow of air.
All or most of the water drops vaporize prior to reaching the heat
exchanger 13.
[0030] Because each of the spray nozzles 21 sprays water drops
downward, even those large water drops that do not vaporize quickly
are dropped downward (onto the installation surface of the outdoor
unit 11 or the like) across the flow of outside air by the force of
the downward spray motion and gravity added to these water drops.
This can prevent adherence of the large water drops to the heat
exchanger 13, whereby the heat exchanger 13 is prevented from being
wet.
[0031] As shown in FIG. 2, the plurality of spray nozzles 21 are
disposed horizontally at intervals on three side panels 12a, 12b,
12c facing the heat exchanger 13 so as to provide the cooling
effect of the spray device 20 to substantially the entire heat
exchanger 13. Specifically, the plurality of nozzles 21 are
disposed horizontally at an interval of, for example, several tens
of centimeters based on a range in which the water drops from each
spray nozzle 21 are spread, i.e., a range in which the outside air
flowing toward the heat exchanger 13 is cooled by each spray nozzle
21.
[0032] The present embodiment illustrates a case in which the range
in which the water drops from each spray nozzle 21 are spread (the
horizontal range) is, for example, approximately 50 cm, the width
of the side panel 12a approximately, for example, 100 cm, and the
width of the side panels 12b, 12c approximately 30 cm. Two spray
nozzles 21 are disposed horizontally at intervals on the side panel
12a, and one spray nozzle 21 on each of the side panels 12b and
12c. Note that these spray nozzles 21 are disposed at the same
height.
[0033] The water supply mechanism 60 includes a liquid feed piping
section 61 and a liquid feed pump 62. The liquid feed piping
section 61 connects a water source, not shown, such as a water
line, and each spray nozzle 21 to each other. The liquid feed
piping section 61 includes a conductive piping section 61a (a metal
piping section 61a, in the present embodiment) that is located on
the upstream side of flow of water, and an insulating piping
section 61b (a resin piping section 61b, in the present embodiment)
that is located on the downstream of the same. The liquid feed pump
62 feeds the water to each of the spray nozzles 21 via the liquid
feed piping section 61.
[0034] The air supply mechanism 70 includes an air feed pump 72
such as a compressor, and an air feed piping section 71. The air
feed piping section 71 connects the air feed pump 72 and each of
the spray nozzles 21 to each other.
[0035] The charging mechanism 80 includes a charging power supply
(a high-voltage power supply) 81, wiring sections 82, 83, and an
output regulator 84. The wiring section 82 connects a positive
electrode of the charging power supply 81 to a leading end portion
of each spray nozzle 21. The wiring section 83 connects a negative
electrode of the charging power supply 81 to the conductive piping
section 61a of the liquid feed piping section 61. This
configuration positively charges the water (water drops) sprayed
from the spray nozzle 21. The positive electrode of the charging
power supply 81 is grounded in such a manner that the spray nozzle
21 becomes a ground potential. The resin piping section 61b is made
of electric insulating synthetic resin and is located downstream of
the connection between the wiring section 83 and the liquid feed
piping section 61. The output regulator 84 regulates an output of
the charging power supply 81.
[0036] Although FIG. 1 shows a state in which the water supply
mechanism 60, the air supply mechanism 70, and the charging
mechanism 80 are connected a single spray nozzle 21, and omits
illustration of the other spray nozzles 21, the water supply
mechanism 60, the air supply mechanism 70, and the charging
mechanism 80 are connected to the other spray nozzles 21 in the
same manner as the one shown in FIG. 1. More specifically, for
example, the liquid feed piping section 61 of the water supply
mechanism 60 branches off in the middle, to be connected to the
plurality of spray nozzles 21, and the air feed piping section 71
of the air supply mechanism 70 also branches off in the middle, to
be connected to the plurality of spray nozzles 21. For instance,
the plurality of spray nozzles 21 are connected in parallel to one
another with respect to the charging power supply 81 of the
charging mechanism 80.
[0037] The outside air temperature sensor 18 is capable of
detecting the outside air temperature. For instance, when the
outside air temperature sensor 18 detects that the outside air
temperature reaches a predetermined temperature or higher, the
controller 16 determines that the load of the cooling operation
exceeds a predetermined level set beforehand, and then controls the
liquid feed pump 62 and the air feed pump 72 to start spraying
water from the plurality of spray nozzles 21. For example, during a
predetermined time period, the controller 16 controls the liquid
feed pump 62 and the air feed pump 72 so that the water is sprayed
continuously or intermittently from each of the spray nozzles 21.
The controller 16 also controls the output regulator 84 of the
charging mechanism 80 and applies a voltage to each of the spray
nozzles 21 by means of the charging power supply 81 in order to
electrically charge water drops sprayed from each of the spray
nozzles 21.
[0038] Next, the structure of the plurality of spray nozzles 21 is
described in detail. In the present embodiment the plurality of
spray nozzles 21 have structures identical to one another. FIG. 3
is a cross-sectional diagram showing one of the spray nozzles 21.
As shown in FIG. 3, the spray nozzle 21 has a body 10, and an
orifice 50 located downstream of the body 10 (on the downstream
side of the direction of water flow).
[0039] The body 10 functions to guide to the orifice 50 water
supplied from the water source, not shown, and to mix fine bubbles
with the water supplied to the body 10. The body 10 of the present
embodiment extends perpendicularly (vertically) and has the orifice
50 disposed downside thereof. In other words, the body 10 of the
present embodiment guides, downward, the water supplied from the
water source that is not shown. The orifice 50 functions to receive
the water that has bubbles mixed therein by the body 10 and is
guided to the orifice 50, stably feed this water mixed with bubbles
to the outside of the spray nozzle 21, and expand the bubbles
discharged from the orifice by taking advantage of the difference
in pressure between the front and back of the orifice, to produce
fine water drops to be sprayed.
[0040] The body 10 has a cylindrical contour with its axis longer
than its diameter. In other words, the body 10 has a cylindrical
contour extending perpendicularly. The body 10 has an air guide
pipe (an outer tubal portion) 31 with a pipe wall formed into the
shape of a pipe, and a water guide pipe (an inner tubal portion) 41
that has a pipe wall formed into the shape of a pipe and is
disposed on the inside of the air guide pipe 31. In other words,
the water guide pipe 41 is inserted into the air guide pipe 31.
[0041] The water guide pipe 41 is provided with a plurality of air
introduction holes 43a pierced through the pipe wall thereof in a
thickness direction. The pipe wall of the air guide pipe 31 is
provided with an air supply portion 32 for supplying air to an air
flow path F1. The air supply portion 32 has a cylindrical shape in
which is formed an air supply hole 32a communicating with the air
flow path F1. The air feed piping section 71 shown in FIG. 1 is
connected to this air supply portion 32.
[0042] An axial direction of the air guide pipe 31 corresponds to
that of the water guide pipe 41. These axes are substantially
aligned on the same straight line. In other words, the air guide
pipe 31 and the water guide pipe 41 are formed into a pipe
extending perpendicularly and are disposed in such a manner that
the central axes thereof completely or roughly coincide with each
other. The water guide pipe 41 has a cylindrical shape with an
inner diameter D1 and outer diameter D2. The air guide pipe 31 has
a cylindrical shape with an inner diameter D3, an outer diameter
D4, and a length L1. The inner diameter D3 of the air guide pipe 31
is greater than the outer diameter D2 of the water guide pipe 41.
An inner circumferential surface of the air guide pipe 31 and an
outer circumferential surface of the water guide pipe 41 are
separated from each other in a radial direction.
[0043] One end of the air guide pipe 31 (a downstream end: a lower
end, in the present embodiment) and one end of the water guide pipe
41 (a downstream end: a lower end, in the present embodiment) are
located at substantially the same position in the axial direction,
and the other end of the water guide pipe 41 (an upstream end: an
upper end, in the present embodiment) is located upstream of the
other end of the air guide pipe 31 (an upstream end: an upper end,
in the present embodiment). Specifically, the section near the
other end of the water guide pipe 41 projects from the other end of
the air guide pipe 31 to the upstream side. One end of the air flow
path F1 (a lower end, in the present embodiment) is closed by the
orifice 50, and the other end of the air flow path F1 (an upper
end, in the present embodiment) is closed by a closing member
33.
[0044] The body 10 has an air guide portion 30, a water guide
portion 40, and a bubble formation portion 43. In the present
embodiment, the water guide portion 40 corresponds to a water flow
path F2 which is defined by an inner circumferential surface of the
pipe wall of the water guide pipe 41. The air guide portion 30
corresponds to the air flow path F1 which is defined by the outer
circumferential surface of the water guide pipe 41 and an inner
circumferential surface of the pipe wall of the air guide pipe 31.
The bubble formation portion 43 has the plurality of air
introduction holes 43a. The plurality of air introduction holes 43a
are disposed at intervals in the circumferential direction and
axial direction of the water guide pipe (the inner tubal portion)
41. The bore diameter of each of the air introduction holes 43a is
smaller than that of the supply hole 32a of the air supply portion
32. The bubble formation portion 43 of the water guide pipe 41
corresponds to a cylindrical section between the air introduction
hole 43a located at the uppermost stream and the air introduction
hole 43a located at the lowermost stream. In the present
embodiment, the water guide portion 40 guides, toward the orifice
50 disposed on the lower side of the body 10, water and air that is
supplied from the air guide portion 30 into the water guide portion
40 via each of the air introduction holes 43a of the bubble
formation portion 43 (i.e., water containing bubbles is guided
perpendicularly downward). As a result, the water and the air
(bubbles) are prevented from drifting as the water with bubbles in
the water guide portion 40 flows. This consequently provides a
great range of stability conditions in which sufficiently fine
water drops are stably sprayed from a spray portion 51 (i.e., a
range in which sufficiently fine water drops are stably sprayed
remains wide even when the flow rates of the water and air supplied
to the spray nozzle 21 are changed).
[0045] The orifice 50 has the spray portion 51 that produces fine
water drops by expanding the bubbles by means of the difference in
pressure between the front and back of the orifice 50 and sprays
the fine water drops, and a closing portion 52 for closing one end
of the air flow path F1. The spray portion 51 of the present
embodiment sprays the fine water drops downward.
[0046] The closing portion 52 is a ring-shaped area located
radially outward, and the spray portion 51 is an area located
radially inward of the closing portion 52. The closing portion 52
has an inner surface (a surface on the upstream side) 52a that
comes into abutment with one end of the air guide pipe 31 and one
end of the water guide pipe 41 to close the end of the air flow
path F1.
[0047] The spray portion 51 has a communication hole communicating
with the water flow path F2 and an external portion of the spray
nozzle 21. The communication hole includes a tapering hole 51a with
a tapering surface, which has an inner diameter becoming smaller
toward the downstream side, and a spray hole 51b that is located on
the downstream side of the tapering hole 51a and sprays water. The
distance between the spray hole 51b and the heat exchanger 13 and
the bore diameter of the spray hole 51b are set so that all or most
of water drops sprayed from the spray hole 51b evaporates
(vaporizes) while moving toward the heat exchanger 13. The bore
diameter of the spray hole 51b is smaller than that of the air
introduction holes 43a described hereinbelow.
[0048] The inner diameter of an upstream-side end portion of the
tapering hole 51a is set to be approximately equal to or slightly
smaller than the inner diameter D1 of one end of the water guide
pipe 41. It is preferred that the end of the water guide pipe 41
and the upstream-side end portion of the tapering hole 51a be
connected smoothly without a difference in height. An axial length
of the tapering hole 51a is greater than an axial length L4 of the
spray hole 51b. Water that flows through the tapering hole 51a
along the tapering surface toward the downstream side reaches the
spray hole 51b, with the flow velocity thereof gradually increased.
The water reaching the spray hole 51b contains a large number of
fine bubbles and is sprayed to the outside of the spray nozzle 21
along with these bubbles. When or after the water containing a
large number of bubbles is sprayed from the spray hole 51b, the
bubbles expand and burst, creating fine water drops.
[0049] Each of the spray nozzle 21 of the present embodiment
includes a supply region A1 provided with the air supply hole 32a,
a bubble formation region A2 provided with the plurality of air
introduction holes 43a, and a guide region A3 for guiding to the
spray portion 51 water that contains a large number of bubbles
formed in the bubble formation region A2. The guide region A3 of
the present embodiment guides downward (specifically, toward the
spray portion 51 provided on the lower side of the body 10) the
water containing a large number of bubbles. The guide region A3
also functions as a dispersion region (a mixing region) for
dispersing a large number of bubbles in the water to some extent.
This guide region A3 is located between the bubble formation region
A2 and the spray portion 51. The bubble formation region A2 is
located downstream of the supply region A1. In other words, the
supply region A1, the bubble formation region A2, the guide region
A3, and the spray portion 51 are arranged axially in this order
toward the downstream side.
[0050] In the present embodiment, a length L2 of the bubble
formation region A2 is greater than the inner diameter D1 of the
water guide pipe 41, in the axial direction of the water guide pipe
41. Therefore, in a wide section in the axial direction, air is
mixed into the water that flows through the water guide pipe 41.
This can efficiently disperse and mix a large number of bubbles
into the water. In addition, a length L3 of the guide region A3 is
greater than the inner diameter D1 of the water guide pipe 41, in
the axial direction of the water guide pipe 41. Therefore, the
large number of bubbles mixed with the water in the bubble
formation region A2 can effectively be dispersed in the water in
the guide region A3.
[0051] Examples of the water source include a water line such as a
water supply system. In this case, the liquid feed piping section
61 is connected to an upstream-side end portion of the water guide
pipe 41. The liquid feed piping section 61 is connected to a
hydrant, not shown. The water is sprayed from the spray nozzle 21
by driving the liquid feed pump 62 and the air feed pump 72. It
should be noted that the liquid feed pump 62 can be omitted, and
the water can be sprayed from the spray nozzle 21 by using the
water pressure of a water line. In this case, the cost for
installing the liquid feed pump 62 and the running cost for driving
the liquid feed pump 62 can be reduced. A tank with water pooled
therein may be used as the water source. In this case, the liquid
feed piping section 61 is connected to a water inlet provided to
the tank.
[0052] It is preferred that the average particle diameter of the
water drops be, for example, 25 .mu.m or less (it takes
approximately 0.3 seconds or less for the water drops to
evaporate). The average particle diameter of the water drops can be
adjusted by adjusting the bore diameter of the spray hole 51b, the
bore diameter of the air introduction hole 43a, the pressure
applied to the water flow path F2, the pressure applied to the air
flow path F1, and the like.
[0053] It is preferred that the ratio between a water supply amount
and an air supply amount be, for example, 0.1 or less in weight
ratio (weight of air/weight of water). Power required to supply air
can be made small by adjusting the weight ratio to this range.
Because the conventional two-fluid nozzle that injects air and
water simultaneously from the spray hole creates fine water drops
by adding shear force to the water at the pressure of the air, the
air needs to be injected at high speeds, requiring a weight ratio
(weight of air/weight of water) of 0.4 or more. For this reason,
the conventional two-fluid nozzle requires great power to supply
air.
Second Embodiment
[0054] FIG. 4 is a cross-sectional diagram showing a spray nozzle
21 of an outdoor unit 11 according to a second embodiment of the
present invention. The outdoor unit 11 according to the second
embodiment is different from the outdoor unit 11 of the first
embodiment in terms of the structure of the spray nozzle 21. The
same reference numerals as those shown in FIG. 3 are applied to the
components of the second embodiment that are the same as those of
the first embodiment, and hence descriptions thereof are omitted
accordingly.
[0055] As shown in FIG. 4, the spray nozzle 21 according to the
second embodiment has the supply region A1 provided with the air
supply hole 32a, the bubble formation region A2, and the guide
region A3 for guiding, to the spray portion 51, water containing a
large number of bubbles formed in the bubble formation region A2,
as with the first embodiment.
[0056] As shown in FIG. 4, the water guide pipe 41 is provided with
the bubble formation portion 43. The bubble formation portion 43
includes a porous portion 42 made of a porous material. The porous
portion 42 is formed from, for example, foam metal. The porous
portion 42 has a large number of air introduction holes 43a. The
bubble formation portion 43 corresponds to the region between the
uppermost stream end of the porous portion 42 and the lowermost
stream end of the same in the water guide pipe 41.
[0057] The porous portion 42 according to the present embodiment
has a cylindrical shape with substantially the same diameter as the
other parts of the water guide pipe 41; however, the shape of the
porous portion 42 is not limited to a cylindrical shape. For
instance, the water guide pipe 41 may be provided with a plurality
of porous portions 42 that are disposed independently from each
other in a scattering manner in a circumferential direction and/or
a direction in which the water guide pipe 41 extends.
[0058] The porous portion 42 has a large number of continuous pores
(the large number of air introduction holes 43a) configured by a
series of pores. Therefore, air flowing through the air flow path
F1 flows into the water flow path F2 via the large number of air
introduction holes 43a. In the second embodiment, the presence of
such porous portion 42 can make the porosity (void ratio) in the
bubble formation region A2 greater than that of the first
embodiment.
Third Embodiment
[0059] FIG. 5 is a cross-sectional diagram showing a spray nozzle
21 of an outdoor unit 11 according to a third embodiment of the
present invention. The outdoor unit 11 according to the third
embodiment is different from the outdoor unit 11 of the first
embodiment in terms of the structure of the spray nozzle 21.
[0060] As shown in FIG. 5, the spray nozzle 21 according to the
third embodiment includes the air guide portion 30, the water guide
portion 40, the bubble formation portion 43, and the spray portion
51. The water guide portion 40 includes a cylindrical water guide
pipe 44. The air guide portion 30 includes a cylindrical air guide
pipe 34 connected to a side (pipe wall) of the water guide pipe 44.
A leading end portion of the air guide pipe 34 is embedded in the
water guide pipe 44. The spray portion 51 is provided at a leading
end portion (downstream-side end portion) of the water guide pipe
44.
[0061] The spray nozzle 21 has the air flow path F1 and the water
flow path F2. The water flow path F2 is a space defined by an inner
circumferential surface of the water guide pipe 44. The air flow
path F1 is a space defined by an inner circumferential surface of
the air guide pipe 34. The outer diameter of the air guide pipe 34
is smaller than the outer diameter of the water guide pipe 44.
[0062] The spray portion 51 has a communication hole communicating
with the water flow path F2 and an external portion of the spray
nozzle 21. The communication hole includes the tapering hole 51a
with a tapering surface, which has an inner diameter becoming
smaller toward the downstream side, and the spray hole 51b that is
located on the downstream side of the tapering hole 51a and sprays
water to the outside.
[0063] The air feed piping section 71 shown in FIG. 1 is connected
to an upstream-side end portion of the air guide pipe 34, and the
liquid feed piping section 61 shown in FIG. 1 is connected to an
upstream-side end portion of the water guide pipe 44. Air supplied
from an air source flows through the air guide pipe 34 and is then
introduced into water through the plurality of air introduction
holes 43a, the water flowing through the water guide pipe 44.
[0064] FIG. 6A is a perspective view showing the air guide pipe 34
of the spray nozzle 21 according to the third embodiment. As shown
in FIG. 6A, the air guide pipe 34 has a cylindrical shape with
outer and inner diameters set to be substantially uniform in an
axial direction.
[0065] The bubble formation portion 43 is located at the leading
end portion of the air guide pipe 34. The bubble formation portion
43 is a circular plate-like body which is disposed in such a manner
as to cover an opening of the leading end portion of the air guide
pipe 34. The plurality of air introduction holes 43a are formed in
a scattering manner throughout the entire area of this plate-like
body. This bubble formation portion 43 is disposed in the water
flow path F2 of the water guide pipe 44.
[0066] In this spray nozzle 21, air is blown out of the plurality
of air introduction holes 43a of the bubble formation portion 43 in
a direction that intersects with a direction in which the water
flows through the water flow path F2 (in a direction perpendicular
to a direction of the water flow, in the present embodiment).
According to such a configuration, the air blown out of the
plurality of air introduction holes 43a can be made fine by shear
force of the water flow. As a result, finer bubbles can be produced
as compared to a case where the air is blown out of the plurality
of air introduction holes 43a toward the downstream side in a
direction parallel to the direction of the water flow in the water
flow path F2.
[0067] FIG. 6B is a perspective view showing modification 1 of the
air guide pipe 34. In this modification 1, an upstream-side section
of the air guide pipe 34 has a cylindrical shape with the outer and
inner diameters set to be substantially uniform in the axial
direction, and a downstream-side (leading end-side) section of the
air guide pipe 34 has a flare shape with the outer and inner
diameters becoming large gradually toward the downstream side. The
leading end portion of the air guide pipe 34 is provided with the
bubble formation portion 43 having the plurality of air
introduction holes 43a.
[0068] Compared to the aspect shown in FIG. 6A, the area of the
plate-like bubble formation portion 43 can be made greater than
that illustrated in modification 1 shown in FIG. 6B. Thus, when the
number of air introduction holes 43a shown in FIG. 6A is same as
that shown in FIG. 6B, the space between the air introduction holes
43a illustrated in modification 1 can be made wider than that
illustrated in the aspect shown in FIG. 6A, preventing
reaggregation of the bubbles.
[0069] FIG. 6C is a perspective view showing modification 2 of the
air guide pipe 34. In this modification 2, the air guide pipe 34
has a cylindrical shape with the outer and inner diameters set to
be substantially uniform in the axial direction. The leading end
portion of the air guide pipe 34 is provided with the bubble
formation portion 43. This bubble formation portion 43 is a porous
body (porous portion) made of a porous material. The porous portion
has the large number of air introduction holes 43a. The porous body
is formed from, for example, foam metal. The porous body has a
large number of continuous pores (the large number of air
introduction holes 43a) configured by a series of pores. In
modification 2, the presence of such porous portion can make the
porosity (void ratio) in the bubble formation portion 43 greater
than that illustrated in the aspects shown in FIGS. 6A and 6B.
[0070] As described above, in each of the embodiments, each spray
nozzle 21 has the air guide portion 30 through which air flows, the
water guide portion 40 through which water flows, the bubble
formation portion 43 that forms a large number of bubbles in the
water by allowing the air of the air guide portion 30 to flow into
the water of the water guide portion 40, and the spray portion 51
that is located downstream of the water guide portion 40 in the
direction of water flow and sprays, to the outside, the water
containing the large number of bubbles which is in the water guide
portion 40. Therefore, each of the embodiments can reduce the power
of the entire air conditioning device while preventing corrosion of
the heat exchanger.
[0071] The first and second embodiments each employ the double pipe
structure in which the air guide pipe 31 is disposed in such a
manner as to surround the outer circumference of the water guide
pipe 41 provided with one or more air introduction holes 43a.
Therefore, each of the spray nozzles 21 having the water guide
portion 40, the air guide portion 30, and the bubble formation
portion 43 can be produced inexpensively.
[0072] In the first and second embodiments, the plurality of air
introduction holes 43a are disposed at intervals in the
circumferential direction of the water guide pipe 41 and the
direction in which the water guide pipe 41 extends. Therefore,
unlike a configuration in which only one air introduction hole 43a
is provided in the water guide pipe 41, the air can be let flow
into the water of the water guide pipe 41 from a plurality of
sections that are disposed at intervals in the circumferential
direction and the direction in which the water guide pipe 41
extends. As a result, the water flowing through the water guide
pipe 41 can have bubbles dispersed efficiently therein. In
addition, compared to the configuration in which only one air
introduction hole 43a is provided, the resistance for letting the
air flow into the water is smaller, and the pressure required to
let the air flow into the water can be set lower, further reducing
the power.
[0073] In the second embodiment, the porosity in the bubble
formation portion 43 can be increased because the bubble formation
portion 43 includes the porous portion 42 with the plurality of air
introduction holes 43a. Such configuration can further reduce the
resistance created when the air is introduced into the water of the
water guide pipe 41 via the bubble formation portion 43. This can
further reduce the pressure required to let the air flow into the
water.
[0074] In the second embodiment, variations in bore diameter of the
plurality of air introduction holes (43a) can be prevented by
forming the porous portion 42 with foam metal, so that the diameter
of bubbles to be formed in the bubble formation portion 43 can be
made somewhat uniform, reducing variations in diameter of water
drops sprayed by the spray portion 51.
[0075] The third embodiment has the water guide pipe 44, and the
air guide pipe 34 that is connected to the water guide pipe 44 and
has one or more air introduction holes 43a at the end portion
thereof on the water guide pipe 44 side. The water guide portion 40
includes the water flow path F2 defined by the inner
circumferential surface of the water guide pipe 44. The air guide
portion 30 has the air flow path F1 defined by the inner
circumferential surface of the air guide pipe 34. The bubble
formation portion 43 includes one or more air introduction holes
43a. In the third embodiment, the spray nozzle 21 can be configured
with such a simple structure.
[0076] Each of the embodiments further has the charging mechanism
80 for electrically charging the water sprayed from each spray
nozzle 21. Each of the water drops sprayed from the spray portion
51 moves through the air while being electrically charged. As a
result, the water drops repel each other with a force of
electrostatic repulsion, preventing reaggregation of the water
drops. This can also prevent an increase in water drop diameters
due to reaggregation. The electrostatic repulsion between the water
drops can spread the water drops across a wide area.
[0077] In each of the embodiments, the water guide portion 40
vertically guides the water containing bubbles. Such configuration
can prevent the water and the air (bubbles) from drifting as the
water with bubbles in the water guide portion 40 flows. This
consequently provides a great range of stability conditions in
which sufficiently fine water drops are stably sprayed from the
spray portion 51 (i.e., a range in which sufficiently fine water
drops are stably sprayed remains wide even when the flow rates of
the water and air supplied to the spray nozzles 21 are changed). In
other words, when vertically guiding the water containing bubbles,
such configuration can prevent the air (bubbles) from coming
together on the upper side when the water containing the bubbles
flows through the water guide portion 40, and from flowing out of
balance along with the water (drifting), as in a case where the
water containing the bubbles is guided in another direction (i.e.,
horizontally). Consequently, even with different flow rates of the
water and air or other conditions for supplying the water and air
to the spray nozzles 21, defective spray (where sufficiently fine
water drops are not produced or where the size of the water drops
fluctuates, etc.) caused due to the drift can be minimized on a
wide scale. As a result, sufficiently fine water drops can stably
be sprayed from the spray portion 51.
[0078] Moreover, according to each of the embodiments, the water
guide portion 40 guides the water containing bubbles downward, and
the spray portion 51 sprays this water downward. Thus, compared to
the configuration in which the water guide portion 40 guides the
water containing bubbles in a different direction (e.g., upward or
horizontally) and the spray portion 51 sprays this water in the
direction, the maximum range of stability conditions (the water/air
supply conditions in which sufficiently fine water drops are stably
sprayed from the spray portion 51) can be obtained.
[0079] In addition, even when the water drops are large and cannot
evaporate easily, the spray portion 51 sprays such large water
drops downward, and the resultant force of the downward spray
motion and gravity added to the water drops cause the water drops
to fall downward (e.g., onto the installation surface of the
outdoor unit 11 or the like) across substantially the horizontal
flow of air directed toward the heat exchanger 13. This
configuration can prevent the heat exchanger 13 from getting wet by
the large water drops.
Other Embodiments
[0080] The embodiments of the present invention are described
above; however, the present invention is not limited to these
embodiments and can be modified and improved in various ways
without departing from the scope of the present invention.
[0081] Each of the embodiments describes the example in which the
spray nozzles 21 are disposed horizontally at intervals on the
three side panels 12a, 12b, 12c facing the heat exchanger 13 so as
to be able to spray water drops downward and to be at the same
height, as shown in FIG. 2. However, the present invention is not
limited to this configuration. As long as the cooling effect of the
spray device 20 can be provided substantially uniformly to
substantially the entire heat exchanger 13, the spray nozzles 21
may be disposed as shown in, for example, the outdoor unit 11A of
FIG. 7, so as to be able to spray water drops toward the heat
exchanger 13 (i.e., to spray water drops along the direction of the
outside air flowing toward the heat exchanger 13). A specific
example of this configuration is described below.
[0082] Each of the spray nozzles 21 is disposed in such a manner as
to spray water drops toward the heat exchanger 13. In other words,
each of the spray nozzles 21 is disposed, with an axial direction
thereof being directed along the direction of the flow of air (air
stream). The water drops sprayed from each spray nozzle 21 move
toward the heat exchanger 13 along the air stream direction while
spreading radially. All or most of the water drops vaporize prior
to reaching the heat exchanger 13.
[0083] When disposing each of the spray nozzles 21 in the outdoor
unit 11A in such a manner as to spray water drops horizontally or
slightly obliquely as described above, it is preferred that the
plurality of spray nozzles 21 be disposed at intervals on the three
side panels 12a, 12b, 12c facing the heat exchanger 13, as shown in
FIG. 8. More specifically, the plurality of spray nozzles 21 are
disposed vertically and horizontally at an interval of, for
example, several tens of centimeters in a scattering manner, based
on the range in which the water drops from each spray nozzle 21 are
spread, i.e., the range in which the air flowing toward the heat
exchanger 13 is cooled by each spray nozzle 21. In this arrangement
example, the diameter of the range in which the water drops sprayed
from each spray nozzle 21 are spread is approximately 50 cm, the
width of the side panel 12a approximately, for example, 100 cm, the
width of the side panels 12b, 12c approximately 30 cm, and the
height of each side panel approximately 80 cm. Four spray nozzles
21 are arranged vertically and horizontally on the side panel 12a,
and two spray nozzles 21a are arranged vertically on each of the
side panels 12b and 12c.
[0084] Arranging the spray nozzles 21 in this manner results in
providing the cooling effect of the spray device 20 substantially
uniformly to substantially the entire heat exchanger 13.
[0085] In a case where the spray nozzles 21 are disposed in such a
manner as to spray water drops toward the heat exchanger 13 (i.e.,
along the direction of outside air flowing toward the heat
exchanger 13), the plurality of spray nozzles 21 may be disposed
unevenly so that, for example, a better cooling effect can be
provided to some areas of the heat exchanger 13 than the other
areas. A specific example of this configuration is described
below.
[0086] FIG. 9 is a schematic diagram for explaining another example
of the arrangement of the spray nozzles 21 in relation to the heat
exchanger 13. The spray nozzles 21 are not shown in FIG. 9. The
heat exchanger 13 shown in FIG. 9 has three heat-transfer pipes P1,
P2, P3. These three heat-transfer pipes P1, P2, P3 each have an
independent refrigerant path. Each of the heat-transfer pipes has a
refrigerant path that meanders through the heat exchanger 13, with
a part bent at either end in a width direction of the heat
exchanger 13. Each heat-transfer pipe is provided with a
refrigerant inlet at its one end (a right end, in FIG. 9), and a
refrigerant outlet at its other end (a left end, in FIG. 9).
[0087] In order to change the refrigerant into supercooled liquid
with a predetermined supercooling degree in the heat exchanger 13,
it is preferred that supercooling regions (downstream-side end
regions) SB1, SB2, SB3 in the vicinity of the refrigerant outlets
of the heat-transfer pipes P1, P2, P3 be cooled intensively. In the
arrangement example shown in FIG. 9, the plurality of spray nozzles
21 are disposed mainly at the positions that face the supercooling
regions SB1, SB2, SB3 in the heat exchanger 13.
[0088] Specific examples of disposing the spray nozzles 21 mainly
in some regions include, for example, an aspect in which the
plurality of spray nozzles 21 are disposed only at the positions
facing the supercooling regions SB1, SB2, SB3 in the heat exchanger
13, and an aspect in which the spray nozzles 21 are disposed more
densely at the positions facing the supercooling regions SB1, SB2,
SB3 than at the positions facing the other regions.
[0089] In addition, for example, each of the spray nozzles 21 may
be disposed in such a manner as to spray water drops upward, as
shown in FIG. 10.
[0090] In this case, the spray nozzles 21 are disposed outside and
below the heat exchanger 13 in the outdoor unit 11B. In this
configuration, in each spray nozzle 21 the water guide portion 40
guides the water containing bubbles upward, and the spray portion
51 sprays, upward, this water containing many bubbles which is
guided by the water guide portion 40. The plurality of spray
nozzles 21 are disposed horizontally at intervals on the three side
panels 12a, 12b, 12c facing the heat exchanger 13, in such a manner
as to spray water drops upward and to be at the same height (below
the heat exchanger 13).
[0091] By allowing the water guide portion 40 to guide the water
containing bubbles upward and allowing the spray portion 51 to
spray this water upward, the air and water are prevented from
drifting as the water with bubbles in the water guide portion 40
flows, allowing the spray portion 51 to stably spray sufficiently
fine water drops.
[0092] Furthermore, because each spray nozzle 21 sprays the water
drops upward from below toward the outside air flowing toward the
heat exchanger 13 which has wind velocity distribution where the
outside air accelerates on the upper side of the heat exchanger 13
(the wind velocity distribution resulting from the positional
relationship between the heat exchanger 13 and the fan 14), flight
durations that are long enough for the water drops to vaporize
prior to reaching various sections of the heat exchanger 13 can be
ensured as the water drops flow toward the various sections in a
height direction of the heat exchanger 13. This mechanism is
described below specifically.
[0093] In the outdoor unit 11B in which the heat exchanger 13 is
provided upright with respect to the installation surface
(horizontal surface) and the fan 14 is disposed above and
horizontally inward of the heat exchanger 13 in the case 2 (see
FIG. 10), a wind velocity distribution shown in FIG. 11 is formed
in which the air flows non-uniformly toward the heat exchanger 13
and accelerates on the upper side of the heat exchanger 13. This is
because the air suctioned through the air inlets (not shown) of the
side panels 12a, 12b, 12c of the case 2 flows faster near the fan
14 (the upper side). Note that the horizontal arrows directed
toward the heat exchanger 13 indicate flows of the outside air
(air) formed as a result of discharging the air of the outdoor unit
11B (the case 2) to the outside by means of the fan 14 (see the
upward arrows in FIG. 11), the outside air flowing toward the heat
exchanger 13. The lengths of the arrows showing these flows of air
represent the wind velocities in the corresponding height
positions.
[0094] In this state, when each spray nozzle 21 sprays the water
drops upward from below the heat exchanger 13, the distance between
the spray nozzle 21 below the heat exchanger 13 and the upper part
of the heat exchanger 13 increases. As a result, the flight
durations that are long enough for the droplets to vaporize can be
ensured, the droplets being the water drops sprayed from the spray
nozzle 21 and flowing toward the upper part of the heat exchanger
13 (see the arrow a in FIG. 11). Therefore, despite the fast flow
of the outside air flowing toward the upper part of the heat
exchanger 13, the water drops can vaporize prior to reaching the
upper part of the heat exchanger 13. On the other hand, although
the distance between the spray nozzle 21 disposed below the heat
exchanger 13 and the lower part of the heat exchanger 13 is short,
the fact that the air flows slowly toward this section of the heat
exchanger 13 can ensure the flight durations that are long enough
for the water drops to evaporate, the water drops being sprayed
from the spray nozzle 21 and flowing toward the lower part of the
heat exchanger 13 (see the arrow (3 in FIG. 11). Consequently, the
water drops can vaporize prior to reaching the lower part of the
heat exchanger 13. As described above, in the outdoor unit 11B, the
positional relationship between the heat exchanger 13 and the fan
14 creates the wind velocity distribution where the air flowing
toward the heat exchanger 13 is faster at the upper side thereof.
In such a configuration where the water drops are sprayed upward
from below the heat exchanger 13, the distance between the spray
nozzle 21 and the heat exchanger 13 in which the water drops travel
to the heat exchanger 13 is longer toward the height positions of
the heat exchanger 13 where the air flows at higher velocities, and
the distance between the spray nozzle 21 and the heat exchanger 13
in which the water drops travel to the heat exchanger 13 is shorter
toward the height positions of the heat exchanger 13 where the air
flows at lower velocities. Owing to this configuration, the flight
durations long enough for the water drops to vaporize can be
ensured. Consequently, the water drops sprayed from the spray
nozzle 21 vaporize prior to reaching the heat exchanger 13,
resulting in preventing the heat exchanger 13 from getting wet by
the water drops sprayed from the spray nozzle 21.
[0095] In each of the embodiments, each spray nozzle 21 is so
shaped as to allow the entire water guide portion 40 to guide water
vertically; however, the shape of the spray nozzle 21 is not
limited thereto. In other words, each spray nozzle 21 may be
configured to allow a section corresponding at least to the guide
region A3 of the water guide portion 40 to guide water vertically
(downward, in each of the embodiments). For example, in the water
guide portion 40 described in each embodiment, a section downstream
of at least the bubble formation portion 43 (to be more specific, a
section of the water guide pipe 41 that is downstream of the
lowermost stream air introduction hole 43a) may guide at least,
vertically, the water containing bubbles toward the spray portion
51. This configuration can effectively prevent the air and the
water from drifting as the water with bubbles in the water guide
portion 40 flows, and stably spray sufficiently fine water drops
from the spray portion 51.
[0096] In each of the embodiments, an electric current is applied
to the water supplied from the water supply mechanism 60
(electrifying the water) as shown in FIG. 1, to charge the water
sprayed from the spray device 20. However, the mechanism of
electrically charging the water is not limited thereto. For
example, the water to be sprayed may be charged by means of static
induction, as shown in FIGS. 12A and 12B, or by discharging
electricity in the air, as shown in FIG. 13. This mechanism is
described below specifically.
[0097] First of all, the method of using static induction is
described with reference to FIGS. 12A and 12B. FIG. 12A is a
schematic diagram for explaining modification 1 of a charging
mechanism 80, and FIG. 12B an enlarged perspective view for
explaining one of the spray nozzles 21 and an induction electrode
85.
[0098] The liquid feed piping section 61 of the water supply
mechanism 60 of the spray device 20 does not have to be provided
with the insulating piping section 61b described in the
embodiments. In other words, the entire liquid feed piping section
61 is formed from a conductive member. It should be noted that, in
the liquid feed piping section 61, at least the region between the
spray nozzle 21 and the section connected to an electrode of the
charging power supply 81 may be formed from a conductive member,
and, for example, the upstream part of the section connected to the
electrode may be formed from an insulating member.
[0099] The charging mechanism 80 has the charging power supply 81
and the induction electrode 85. The charging power supply 81 has
one of its electrodes connected to the spray nozzle 21, and the
other one to the induction electrode 85. The charging power supply
81 can therefore apply a voltage between the spray nozzle 21 and
the induction electrode 85. In the present embodiment, the positive
electrode is connected to the spray nozzle 21, and the negative
electrode to the induction electrode 85. Therefore, the water
(water drops) sprayed from the spray nozzle 21 is charged
positively. The positive electrode of the charging power supply 81
is grounded such that the spray nozzle 21 becomes the ground
potential.
[0100] The induction electrode 85 is disposed with a predetermined
distance from the spray nozzle 21, and generates static induction
in water passing through the spray nozzle 21, by means of a
predetermined voltage applied between the induction electrode 85
and the spray nozzle 21. More specifically, the induction electrode
85 is an annular electrode with an inner diameter larger than an
outer diameter of the spray nozzle 21 (see FIG. 12B). This
induction electrode 85 is disposed at the leading end of the spray
nozzle 21 in the axial direction of the spray nozzle 21 or at a
position slightly close to the base end of the spray nozzle 21 with
respect to the leading end, in such a manner that a central axis of
the induction electrode 85 matches the axis (central axis) of the
spray nozzle 21. The induction electrode 85 may be disposed in
front of the spray nozzle 21 (toward the heat exchanger) in the
axial direction of the spray nozzle 21. However, in view of the
possibility of contamination of the induction electrode 85 by the
mist-like water sprayed from the spray nozzle 21, it is preferred
that the induction electrode 85 be disposed at the leading end of
the spray nozzle 21 or at the position slightly close to the base
end with respect to the leading end, as described above.
[0101] In this charging mechanism 80, the charging power supply 81
applies a predetermined voltage (e.g., 5000 V to 10000 V) between
the spray nozzle 21 and the induction electrode 85, and thereby
static induction is generated in the water passing through the
spray nozzle 21. The water in this state is sprayed from the spray
nozzle 21, charging the resultant water drops.
[0102] Next is described, with reference to FIG. 13, the method of
discharging electricity to charge the water to be sprayed. FIG. 13
is a schematic diagram for explaining modification 2 of the
charging mechanism 80.
[0103] As with the flow path portion of the static induction
method, the liquid feed piping section 61 of the water supply
mechanism 60 of the spray device 20 in this method does not have to
be provided with the insulating piping section described in the
embodiments.
[0104] The charging mechanism 80 has the charging power supply 81
and a pair of discharge electrodes (a first discharge electrode 86
and a second discharge electrode 87).
[0105] The charging power supply 81 has the positive electrode
thereof connected to the first discharge electrode 86 and the
negative electrode to the second discharge electrode 87. The
negative electrode is grounded such that the second discharge
electrode 87 becomes the ground potential. The charging power
supply 81 therefore can apply a voltage between the first discharge
electrode 86 and the second discharge electrode 87 (between the
pair of discharge electrodes).
[0106] The pair of discharge electrodes 86, 87 is disposed in such
a manner as to sandwich a region through which the mist-like water
sprayed from the spray nozzle 21 passes.
[0107] In this charging mechanism 80, the charging power supply 81
applies a predetermined voltage (e.g., 5000 V to 10000 V) between
the pair of the discharge electrodes 86, 87, and thereby a
discharge (e.g., a corona discharge) is generated between the
discharge electrodes 86, 87. Due to this discharge, the water drops
passing between the discharge electrodes 86, 87 are charged. In
this case, the water drops are charged positively.
[0108] In the charging mechanism (the charging mechanism in the
method of electrifying the water) 80 according to each embodiment,
the water flowing through the insulating piping section 61b is
electrified due to the application of a voltage between the spray
nozzle 21 and the metal piping section 61a, with the insulating
piping section 61b therebetween, as shown in FIG. 1. As a result,
the water to be sprayed becomes charged, but the position to
electrify the water is not limited to the insulating piping section
61b. For instance, when the water supply mechanism 60 is provided
with a water source such as a tank, water pooled in this water
source may be electrified to charge the water, and the charged
water may be supplied to the spray nozzle. This is a method of
charging water through electrification, but in this case the water
guide pipe of the water supply mechanism does not have to be
provided with the insulating piping section.
[0109] Each of the embodiments describes the example in which the
spray device 20 has the charging mechanism 80 as a charger;
however, the charger is not a required component in the present
invention and therefore can be omitted. In case of omitting the
charger, the resin piping section 61b is not required, so the
entire liquid feed piping section 61 can be formed using the metal
piping section 61a.
[0110] The first and second embodiments each describe the example
of providing the guide region A3 between the bubble formation
region A2 and the spray portion 51; however, the guide region A3
can be omitted. In such a case, the air introduction holes 43a can
be formed in the vicinity of the tapering hole 51a of the water
guide pipe 41. However, in the aspect in which the guide region A3
is provided as shown in FIG. 3, the large number of bubbles mixed
in the water can be dispersed in the water more easily than when
the guide region A3 is not provided. Thus, more uniform water drops
can be sprayed from the spray portion 51.
[0111] Each of the embodiments illustrates the example of
positioning the fan 14 downstream of the heat exchanger 13 in the
direction of the airflow. However, the present invention is not
limited to this configuration. For example, the fan 14, the spray
nozzles 21, and the heat exchanger 13 may be disposed in this order
toward the downstream side in the direction of the airflow.
[0112] The second and third embodiments each describe the example
of forming the porous portion 42 with foam metal. However, the
present invention is not limited to this configuration. The porous
portion 42 may not necessarily be formed from metal but can be
formed from, for example, synthetic resin.
[0113] The third embodiment illustrates the situation where the air
guide pipe (the second guide pipe) 34 is connected to a side of the
water guide pipe (the first guide pipe) 44. However, the present
invention is not limited to this configuration. For instance, the
air guide pipe 34 may be connected to a longitudinal end portion
(upstream-side end portion) of the water guide pipe 44. In this
case, the direction in which the water guide pipe 44 extends is
substantially the same as the direction in which the air guide pipe
34 extends.
[0114] The embodiments are summarized hereinbelow.
[0115] (1) According to each of the embodiments, the present
invention can reduce the power of the entire air conditioning
device while preventing corrosion of the heat exchanger thereof.
This mechanism is described hereinafter specifically.
[0116] In other words, in each of the embodiments, water containing
a large number of bubbles are formed in the water guide portion
(40), and this water containing a large number of bubbles is
sprayed from the spray portion (51). When or after the water
containing bubbles is sprayed from the spray portion (51), the
bubbles burst, creating fine droplets. Thus created fine droplets
easily vaporize (evaporate) prior to reaching the heat exchanger
(13), preventing adherence of the droplets to the heat exchanger
(13). In this manner, corrosion of the heat exchanger (13) is
prevented.
[0117] Once the droplets vaporize prior to reaching the heat
exchanger (13), the air flowing toward the heat exchanger (13) is
cooled by its latent heat (vaporization heat). Therefore, because
the temperature of the air passing through the heat exchanger (13)
becomes lower than that obtained when the water is not sprayed, the
power required to drive the compressor, the fan and the like at the
time of the cooling operation of the air conditioning device can be
reduced. Moreover, in the present configuration, no large power is
required to spray air to water at high speeds through the injection
hole of the spray nozzle, as seen in the conventional two-fluid
nozzle. In other words, because the present configuration only
requires power for forming a large number of bubbles in the water
flowing through the water guide portion (40), the amount of air
required is lower than that of the conventional nozzle, enabling to
make the power required to feed air lower than that required in the
conventional nozzle. This configuration can effectively reduce the
power of the entire air conditioning device.
[0118] (2) In the outdoor unit, as an example, the water guide
portion (40) has a pipe wall shaped into a pipe, and also has one
or more air introduction holes (43a) penetrating the pipe wall in
the thickness direction. The air guide portion (30) is shaped into
a pipe so as to surround the outer circumference of the water guide
portion (40).
[0119] According to this configuration, each spray nozzle (21) can
be produced at low costs by adopting the double pipe structure in
which the air guide portion (30) is disposed so as to surround the
outer circumference of the water guide portion (40) provided with
one or more air introduction holes (43a).
[0120] (3) In the outdoor unit, it is preferred that the water
guide portion (40) have the plurality of air introduction holes
(43a) and that the plurality of air introduction holes (43a) be
disposed at intervals in the circumferential direction of the water
guide portion (40) and the direction in which the water guide
portion (40) extends.
[0121] According to this configuration, because the plurality of
air introduction holes (43a) are provided at intervals in the
circumferential direction of the water guide portion (40) and the
direction in which the water guide portion (40) extends, the air
can be let flow into the water of the water guide portion (40)
through the plurality of intervals provided in the circumferential
direction and the direction in which the water guide portion (40)
extends, unlike a configuration having one air introduction hole
(43a). Therefore, the bubbles can efficiently be dispersed in the
water flowing through the water guide portion (40). In addition,
the resistance for letting the air flow in the water becomes
smaller than that obtained in the configuration having one air
introduction hole (43a), enabling to lower the pressure required to
let the air flow into the water. As a result, the power can further
be reduced.
[0122] (4) In the outdoor unit, the water guide portion (40) may be
shaped into a pipe and have, at least partially, the porous portion
(42), and the air guide portion (30) may be shaped into a pipe so
as to surround the outer circumference of the water guide portion
(40).
[0123] According to this configuration, because the water guide
portion (40) has the porous portion (42), the bubbles can have a
uniform diameter, reducing variations in diameter of droplets
sprayed by the spray portion (51).
[0124] (5) In the outdoor unit, the porous portion (42) is formed
from foam metal.
[0125] According to this configuration, the porous portion (42) is
formed from foam metal. Owing to a large porosity of the porous
portion (42), the resistance that is generated when introducing the
air into the water of the water guide pipe (41) through the porous
portion (42) can be reduced. As a result, the pressure required to
let the air flow into the water can be lowered.
[0126] (6) In the outdoor unit, the water guide portion (40) may be
shaped into a pipe. The air guide portion (30) may also be shaped
into a pipe and have a leading end portion thereof connected to the
water guide portion (40).
[0127] According to this configuration, each of the spray nozzles
21 can be configured with a simple structure in which the air guide
portion (30) is connected to the water guide portion (40).
[0128] (7) In the outdoor unit, it is preferred that the air guide
portion (30) have the porous portion (42) at the leading end
portion thereof.
[0129] According to this configuration, because the air guide
portion (30) has the porous portion (42), the bubbles can have a
uniform diameter, reducing variations in diameter of droplets
sprayed by the spray portion (51).
[0130] (8) It is preferred that the outdoor unit further have a
charger (80) for electrically charging the water sprayed from the
spray nozzle (21).
[0131] According to this configuration, the droplets to be sprayed
from the spray portion (51) move through the air while being
charged. This means that the droplets repel each other with a force
of electrostatic repulsion, preventing reaggregation of the
droplets. This can also prevent an increase in droplet diameters
due to reaggregation. The electrostatic repulsion between the
droplets can spread the droplets across a wide area.
[0132] (9) In the outdoor unit (11) of the air conditioning device,
it is preferred that the water guide portion (40) vertically guide
the water containing bubbles.
[0133] In such an aspect where the water guide portion (40)
vertically guides the water containing bubbles, the water and the
air (bubbles) are prevented from drifting as the water with bubbles
in the water guide portion (40) flows. This consequently provides a
great range of stability conditions in which sufficiently fine
droplets are stably sprayed from the spray portion (51). In other
words, a range in which sufficiently fine droplets are stably
sprayed remains wide even when the flow rates of the water and air
supplied to the spray nozzle (21) are changed. Specifically, when
perpendicularly guiding the water containing bubbles, the
above-described configuration can prevent the air (bubbles) from
coming together on the upper side when the water containing the
bubbles flows through the water guide portion (40), and then
flowing out of balance along with the water (drifting), as in a
case where the water containing bubbles is guided in another
direction (i.e., horizontally). Consequently, even with different
flow rates of the water and air or other conditions for supplying
the water and air to the spray nozzle (21), defective spray (where
sufficiently fine droplets are not produced or where the size of
the droplets fluctuates, etc.) caused due to the drift can be
minimized on a wide scale. As a result, sufficiently fine droplets
can stably be sprayed from the spray portion (51).
[0134] (10) In such a case where the guide water portion (40)
vertically guides the water containing bubbles, it is preferred
that the spray nozzle (21) be disposed outside the heat exchanger
(13) in the outdoor unit (11), that the water guide portion (40)
guide the water containing bubbles downward, and that the spray
portion (51) be disposed on the lower side of the water guide
portion (40) and spray, downward, the water containing a large
number of bubbles that is guided by the water guide portion
(40).
[0135] Compared to a configuration in which the water guide portion
(40) guides the water containing bubbles in a different direction
(e.g., upward or horizontally) and the spray portion (51) sprays
this water in the direction, allowing the water guide portion (40)
to guide the water containing bubbles downward and the spray
portion (51) to spray this water downward can provide the maximum
range of stability conditions. In other words, this configuration
can realize the maximum range of water/air supply conditions in
which sufficiently fine droplets are stably sprayed from the spray
portion (51).
[0136] Moreover, because even large droplets are sprayed downward
from the spray portion (51), these large droplets are dropped
across a substantially horizontal flow of air directed toward the
heat exchanger (13) by the force of spray and gravity added to
these droplets. Therefore, even when large droplets are sprayed,
this configuration can prevent adherence of the large droplets to
the heat exchanger (13), whereby the heat exchanger (13) is
prevented from being wet
[0137] (11) When the water guide portion (40) vertically guides the
water containing bubbles, the outdoor unit (11) may have the fan
(14) that forms flow of air directed toward the heat exchanger
(13), wherein the fan (14) is disposed above and inward of the heat
exchanger (13) in the outdoor unit (11) and discharges upward, to
the outside of the outdoor unit (11), air that has flowed into the
outdoor unit (11) and been subjected to heat exchange by the heat
exchanger (13), the spray nozzle (21) is disposed further toward an
outer side than the heat exchanger (13) in the outdoor unit (11),
the water guide portion (40) guides the water containing bubbles
upward, and wherein the spray portion (51) is disposed on the upper
side of the water guide portion (40) and sprays upward the water
containing a large number of bubbles that is guided by the water
guide portion (40).
[0138] By allowing the water guide portion (40) to guide the water
containing bubbles upward and allowing the spray portion (51) to
spray this water upward, the air and water are prevented from
drifting as the water with bubbles in the water guide portion (40)
flows, allowing the spray portion (51) to stably spray sufficiently
fine droplets.
[0139] In addition, because the spray nozzle (21) sprays droplets
upward with respect to the flow of air directed toward the heat
exchanger (13), the flow of air having a wind velocity distribution
where the air accelerates on the upper side of the heat exchanger
(13) (the wind velocity distribution resulting from the positional
relationship between the heat exchanger (13) and the fan (14): see
FIG. 11), flight durations that are long enough for the droplets to
vaporize prior to reaching various sections of the heat exchanger
(13) can be ensured, the droplets flowing toward the various
sections in a height direction of the heat exchanger (13). Such a
configuration can prevent the heat exchanger (13) from getting wet
by the droplets. This mechanism is described hereinbelow
specifically.
[0140] The distance between the spray nozzle (21) below the heat
exchanger (13) and the upper part of the heat exchanger (13)
increases. As a result, flight durations that are long enough for
the droplets to vaporize can be ensured as the droplets are sprayed
from the spray nozzle (21) and flow toward the upper part of the
heat exchanger (13). Therefore, despite the fast flow of the air
flowing toward the upper part of the heat exchanger (13), the
droplets can vaporize prior to reaching the upper part of the heat
exchanger (13). On the other hand, although the distance between
the spray nozzle (21) below the heat exchanger (13) and the lower
part of the heat exchanger (13) is short, the fact that the air
flows slowly toward this section can ensure the flight durations
that are long enough for the droplets to vaporize as the droplets
are sprayed from the spray nozzle (21) and flow toward the lower
part of the heat exchanger (13). Consequently, the water drops can
vaporize prior to reaching the lower part of the heat exchanger
(13). As described above, in the outdoor unit (11), the positional
relationship between the heat exchanger (13) and the fan (14)
creates the wind velocity distribution where the air flowing toward
the heat exchanger (13) is faster at the upper side thereof. In
such a configuration where the droplets are sprayed upward from the
spray nozzle (21), the distance between the spray nozzle (21) and
the heat exchanger (13) in which the droplets travel to the heat
exchanger (13) becomes longer toward the height positions of the
heat exchanger (13) where the air flows at higher velocities, and
the distance between the spray nozzle (21) and the heat exchanger
(13) in which the droplets travel to the heat exchanger (13)
becomes shorter toward the height positions of the heat exchanger
(13) where the air flows at lower velocities. Owing to this
configuration, the flight durations long enough for the droplets to
vaporize can be ensured. Consequently, the droplets sprayed from
the spray nozzle (21) vaporize prior to reaching the heat exchanger
(13), resulting in preventing the heat exchanger (13) from getting
wet by the droplets sprayed from the spray nozzle (21).
[0141] As described above, each of the embodiments can reduce the
power of the entire air conditioning device while preventing
corrosion of the heat exchanger thereof.
EXPLANATION OF REFERENCE NUMERALS
[0142] 11, 11A, 11B Outdoor unit [0143] 13 Heat exchanger [0144] 20
Spray device [0145] 21 Spray nozzle [0146] 30 Air guide portion
[0147] 31 Air guide pipe [0148] 34 Air guide pipe (second guide
pipe) [0149] 40 Water guide portion [0150] 41 Water guide pipe
[0151] 42 Porous body [0152] 44 Water guide pipe (first guide pipe)
[0153] 50 Orifice [0154] 51 Spray portion [0155] 80 Charger
* * * * *