U.S. patent application number 15/512676 was filed with the patent office on 2017-10-12 for air-conditioning-device indoor unit.
This patent application is currently assigned to DAIKIN INDUSTRIES, LTD.. The applicant listed for this patent is DAIKIN INDUSTRIES, LTD.. Invention is credited to Nobuyuki KOJIMA, Akira KOMATSU, Masaaki MURATA.
Application Number | 20170292732 15/512676 |
Document ID | / |
Family ID | 55629717 |
Filed Date | 2017-10-12 |
United States Patent
Application |
20170292732 |
Kind Code |
A1 |
KOJIMA; Nobuyuki ; et
al. |
October 12, 2017 |
AIR-CONDITIONING-DEVICE INDOOR UNIT
Abstract
Disclosed herein is an indoor unit including: a load detector
for detecting a heavy-load area to bear a relatively heavy
air-conditioning load during a heating mode of operation and a
light-load area to bear a lighter air-conditioning load than the
heavy-load area from a perimeter zone of a space to be
air-conditioned; and an air volume adjuster for setting the volume
of air blown toward the light-load area to be lower than that of
air blown toward the heavy-load area in a horizontal blowing mode.
This allows the entire room, including the perimeter zone, to be
air-conditioned efficiently during the heating mode of operation
with temperature non-uniformity reduced in the room.
Inventors: |
KOJIMA; Nobuyuki; (Osaka,
JP) ; KOMATSU; Akira; (Osaka, JP) ; MURATA;
Masaaki; (Osaka, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DAIKIN INDUSTRIES, LTD. |
Osaka-shi, Osaka |
|
JP |
|
|
Assignee: |
DAIKIN INDUSTRIES, LTD.
Osaka-shi, Osaka
JP
|
Family ID: |
55629717 |
Appl. No.: |
15/512676 |
Filed: |
July 28, 2015 |
PCT Filed: |
July 28, 2015 |
PCT NO: |
PCT/JP2015/003774 |
371 Date: |
March 20, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F24F 2110/00 20180101;
F24F 11/30 20180101; F24F 11/76 20180101; F24F 2120/10 20180101;
F24F 11/89 20180101; F24F 1/0014 20130101; F24F 11/79 20180101;
F24F 11/74 20180101; F24F 2120/20 20180101; F24F 1/0047 20190201;
F24F 2140/50 20180101 |
International
Class: |
F24F 11/00 20060101
F24F011/00; F24F 11/04 20060101 F24F011/04; F24F 1/00 20060101
F24F001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 30, 2014 |
JP |
2014-199800 |
Claims
1. An air conditioner indoor unit comprising a casing mounted on a
ceiling of a space to be air-conditioned, the casing having a
plurality of air outlets configured to blow air in multiple blowing
directions in a horizontal blowing mode, wherein the indoor unit
further comprises: a load detector configured to detect a
heavy-load area to bear a relatively heavy air-conditioning load
during a heating mode of operation and a light-load area to bear a
lighter air-conditioning load than the heavy-load area from a
perimeter zone of the space to be air-conditioned; an air volume
adjuster configured to perform an air volume adjustment operation
such that a smaller volume of air is blown toward the light-load
area than toward the heavy-load area in the horizontal blowing
mode; and an operation controller including an air volume
controller configured to control the air volume adjustment
operation by the air volume adjuster.
2. The air conditioner indoor unit of claim 1, wherein the air
volume controller performs control that allows a greater volume of
air to be blown toward the heavy-load area during the air volume
adjustment operation in the horizontal blowing mode than during an
operation in which air is blown uniformly in all directions.
3. The air conditioner indoor unit of claim 1, wherein the air
volume adjuster is configured as airflow direction adjusting vanes
provided for the air outlets, and the air volume controller sets
the area of a gap between respective opening edges of the air
outlets through which air is blown toward the light-load area and
respective peripheral edges of the airflow direction adjusting
vanes to be smaller than the area of a gap between the respective
opening edges of the air outlets through which the air is blown
toward the heavy-load area and the respective peripheral edges of
the airflow direction adjusting vanes by adjusting an angle of the
airflow direction adjusting vanes during the air volume adjustment
operation.
4. The air conditioner indoor unit of claim 1, wherein the
operation controller is configured to select the horizontal blowing
mode from a plurality of blowing modes.
5. The air conditioner indoor unit of claim 1, comprising an input
device allowing a user to indicate whether or not there is any wall
surface in the space to be air-conditioned, wherein the air volume
controller performs control that restricts the air blowing
direction to a direction leading to the wall surface during the air
volume adjustment operation in the horizontal blowing mode.
6. The air conditioner indoor unit of claim 2, wherein the air
volume adjuster is configured as airflow direction adjusting vanes
provided for the air outlets, and the air volume controller sets
the area of a gap between respective opening edges of the air
outlets through which air is blown toward the light-load area and
respective peripheral edges of the airflow direction adjusting
vanes to be smaller than the area of a gap between the respective
opening edges of the air outlets through which the air is blown
toward the heavy-load area and the respective peripheral edges of
the airflow direction adjusting vanes by adjusting an angle of the
airflow direction adjusting vanes during the air volume adjustment
operation.
7. The air conditioner indoor unit of claim 2, wherein the
operation controller is configured to select the horizontal blowing
mode from a plurality of blowing modes.
8. The air conditioner indoor unit of claim 3, wherein the
operation controller is configured to select the horizontal blowing
mode from a plurality of blowing modes.
9. The air conditioner indoor unit of claim 6, wherein the
operation controller is configured to select the horizontal blowing
mode from a plurality of blowing modes.
10. The air conditioner indoor unit of claim 2, comprising an input
device allowing a user to indicate whether or not there is any wall
surface in the space to be air-conditioned, wherein the air volume
controller performs control that restricts the air blowing
direction to a direction leading to the wall surface during the air
volume adjustment operation in the horizontal blowing mode.
11. The air conditioner indoor unit of claim 3, comprising an input
device allowing a user to indicate whether or not there is any wall
surface in the space to be air-conditioned, wherein the air volume
controller performs control that restricts the air blowing
direction to a direction leading to the wall surface during the air
volume adjustment operation in the horizontal blowing mode.
12. The air conditioner indoor unit of claim 4, comprising an input
device allowing a user to indicate whether or not there is any wall
surface in the space to be air-conditioned, wherein the air volume
controller performs control that restricts the air blowing
direction to a direction leading to the wall surface during the air
volume adjustment operation in the horizontal blowing mode.
13. The air conditioner indoor unit of claim 6, comprising an input
device allowing a user to indicate whether or not there is any wall
surface in the space to be air-conditioned, wherein the air volume
controller performs control that restricts the air blowing
direction to a direction leading to the wall surface during the air
volume adjustment operation in the horizontal blowing mode.
14. The air conditioner indoor unit of claim 7, comprising an input
device allowing a user to indicate whether or not there is any wall
surface in the space to be air-conditioned, wherein the air volume
controller performs control that restricts the air blowing
direction to a direction leading to the wall surface during the air
volume adjustment operation in the horizontal blowing mode.
15. The air conditioner indoor unit of claim 8, comprising an input
device allowing a user to indicate whether or not there is any wall
surface in the space to be air-conditioned, wherein the air volume
controller performs control that restricts the air blowing
direction to a direction leading to the wall surface during the air
volume adjustment operation in the horizontal blowing mode.
16. The air conditioner indoor unit of claim 9, comprising an input
device allowing a user to indicate whether or not there is any wall
surface in the space to be air-conditioned, wherein the air volume
controller performs control that restricts the air blowing
direction to a direction leading to the wall surface during the air
volume adjustment operation in the horizontal blowing mode.
Description
TECHNICAL FIELD
[0001] The present invention relates to an indoor unit for an air
conditioner, and more particularly relates to a technique for
controlling an airflow while an indoor unit mounted on a ceiling is
performing a heating mode of operation.
BACKGROUND ART
[0002] Some known air conditioners adopt a so-called "zoned air
conditioning" technique, in which the target space is divided into
a perimeter zone and an interior zone to be air-conditioned
separately, and change their mode of operation according to a given
air-conditioning load in the perimeter zone (see, for example,
Patent Document 1).
[0003] The air conditioner disclosed in Patent Document 1 uses a
floor indoor unit. This air conditioner is configured to blow air
through an upper air outlet of the indoor unit when a heavy
air-conditioning load is imposed in the perimeter zone while the
target space to be air-conditioned is being heated and to start
blowing the air through a lower air outlet to heat the air at the
user's feet when the air-conditioning load in the perimeter zone
decreases.
CITATION LIST
Patent Document
[0004] PATENT DOCUMENT 1: Japanese Unexamined Patent Publication
No. H04-028946
SUMMARY OF INVENTION
Technical Problem
[0005] The air conditioner disclosed in Patent Document 1 is
designed to blow the air through the upper air outlet by detecting
the load in the perimeter zone. Even so, the air conditioner still
blows the air-conditioning air toward the entire perimeter zone.
That is why any significant non-uniformity in the air-conditioning
load in the perimeter zone hampers the air conditioner from
conditioning the air efficiently enough.
[0006] Meanwhile, a ceiling-mounted air conditioner indoor unit is
generally designed to perform a heating mode of operation by
blowing air-conditioning air downward in order to heat the interior
zone and supply that heated air to the perimeter zone. This type of
airflow control, however, could form a non-uniform temperature
distribution inside the room, because part of the heated air
downwardly blown by the indoor unit would rise, instead of falling
and reaching out for the perimeter, to decrease the volume of the
air reaching the perimeter.
[0007] In view of the foregoing background, it is therefore an
object of the present invention to provide a technique for
air-conditioning the entire target space, including the perimeter
zone, efficiently with the temperature non-uniformity reduced while
performing a heating mode of operation.
Solution to the Problem
[0008] A first aspect of the present disclosure is directed to an
air conditioner indoor unit including a casing (20) mounted on a
ceiling (U) of a space to be air-conditioned (R). The casing (20)
has a plurality of air outlets (24, 25) configured to blow air in
multiple blowing directions in a horizontal blowing mode.
[0009] This indoor unit further includes: a load detector (71)
configured to detect a heavy-load area to bear a relatively heavy
air-conditioning load during a heating mode of operation and a
light-load area to bear a lighter air-conditioning load than the
heavy-load area from a perimeter zone of the space to be
air-conditioned (R); an air volume adjuster (50) configured to
perform an air volume adjustment operation such that a smaller
volume of air is blown toward the light-load area than toward the
heavy-load area in the horizontal blowing mode; and an operation
controller (70) including an air volume controller (72) configured
to control the air volume adjustment operation by the air volume
adjuster (50). As used herein, the "horizontal blowing mode" refers
to a mode in which the air is blown substantially horizontally (or
may be slightly obliquely downward) such that the air can reach a
location distant from the indoor unit (11) in the room.
[0010] According to this first aspect, performing the air volume
adjustment operation in the horizontal blowing mode during a
heating mode of operation results in a smaller volume of the air
blown toward the light-load area than the air blown toward the
heavy-load area. Stated otherwise, this results in a larger volume
of the air blown toward the heavy-load area than the air blown
toward the light-load area. As can be seen, a greater volume of air
is blown toward the heavy-load area that is at a lower temperature
than in the light-load area while air is being blown in the
horizontal blowing mode. Thus, according to the present invention,
the heavy-load area of the perimeter zone is supplied with heated
air first to have its temperature raised, resulting in a less
significant temperature difference between the light-load area and
the heavy-load area.
[0011] A second aspect of the present disclosure is an embodiment
of the first aspect of the present disclosure. In the second
aspect, the air volume controller (72) performs control that allows
a greater volume of air to be blown toward the heavy-load area
during the air volume adjustment operation in the horizontal
blowing mode than during an operation in which air is blown
uniformly in all directions.
[0012] According to this second aspect, a greater volume of air is
blown toward the heavy-load area during the air volume adjustment
operation than during an operation in which air is blown uniformly
in all directions, and therefore, heated air blown by the indoor
unit is reliably supplied to the heavy-load area. This reduces the
temperature difference between the light- and heavy-load areas with
reliability.
[0013] A third aspect of the present disclosure is an embodiment of
the first or second aspect of the present disclosure. In the third
aspect, the air volume adjuster (50) is configured as airflow
direction adjusting vanes (51) provided for the air outlets (24,
25). The air volume controller (72) sets the area of a gap between
respective opening edges of the air outlets (24, 25) through which
air is blown toward the light-load area and respective peripheral
edges of the airflow direction adjusting vanes (51) to be smaller
than the area of a gap between the respective opening edges of the
air outlets (24, 25) through which the air is blown toward the
heavy-load area and the respective peripheral edges of the airflow
direction adjusting vanes (51) by adjusting an angle of the airflow
direction adjusting vanes (51) during the air volume adjustment
operation.
[0014] According to this third aspect, adjusting the angle of the
airflow direction adjusting vanes (51) using the air volume
controller (72) during the air volume adjustment operation sets the
area of a gap between respective opening edges of the air outlets
(24, 25) through which air is blown toward the light-load area and
respective peripheral edges of the airflow direction adjusting
vanes (51) to be smaller than the area of a gap at the air outlets
through which the air is blown toward the heavy-load area, thus
resulting in greater ventilation resistance. This decreases the
volume of the air blown toward the light-load area and relatively
increases the volume of the air blown toward the heavy-load area.
In addition, the volume of the air blown toward the heavy-load area
becomes greater than that of the air during the operation in which
the air is blown uniformly in all directions. Consequently, this
decreases the temperature difference between the light- and
heavy-load areas with reliability.
[0015] A fourth aspect of the present disclosure is an embodiment
of any one of the first to third aspects of the present disclosure.
In the fourth aspect, the operation controller (70) is configured
to select the horizontal blowing mode from a plurality of blowing
modes (e.g., the horizontal blowing mode and a downward blowing
mode).
[0016] According to this fourth aspect, the horizontal blowing mode
may be selected from a plurality of blowing modes and the air
volume adjustment operation may be performed in the horizontal
blowing mode. Thus, if the load in the heavy-load area has
increased to beyond a predetermined value in the perimeter zone
while operation is being performed in another mode, the air volume
adjustment operation may be performed as needed in the horizontal
blowing mode so as to reduce the temperature difference between the
light- and heavy-load areas.
[0017] A fifth aspect of the present disclosure is an embodiment of
any one of the first to fourth aspects of the present disclosure.
In the fifth aspect, the air conditioner indoor unit further
includes an input device (73) allowing a user to indicate whether
or not there is any wall surface (W) in the space to be
air-conditioned (R). The air volume controller (72) performs
control that restricts the air blowing direction to a direction
leading to the wall surface (W) during the air volume adjustment
operation in the horizontal blowing mode.
[0018] According to this fifth aspect, the input device (73) allows
the user to indicate whether or not there is any wall surface (W),
thus enabling the air conditioner to perform the air volume
adjustment operation with the air blowing direction restricted to a
direction leading to the wall surface. Blowing air in a direction
leading to no wall surfaces would produce no circulating airflow in
the space to be air-conditioned (R). However, blowing the air in
such a direction leading to a wall surface would produce a
circulating airflow there, thus making the temperature in the space
to be air-conditioned (R) uniform.
Advantages of the Invention
[0019] According to the first aspect of the present disclosure, the
load detector (71) may detect a heavy-load area to bear a
relatively heavy air-conditioning load during a heating mode of
operation and a light-load area to bear a lighter air-conditioning
load than the heavy-load area from a perimeter zone of the space to
be air-conditioned (R). Then, the air volume controller (72) of the
operation controller (70) controls the air volume adjuster (50) in
the horizontal blowing mode to perform an air volume adjustment
operation such that a smaller volume of air is blown toward the
light-load area than toward the heavy-load area, which results in a
less significant temperature difference between the heavy- and
light-load areas. This reduces temperature non-uniformity in the
space to be air-conditioned, thus enabling highly efficient heating
mode of operation.
[0020] According to the second aspect of the present disclosure, a
greater volume of air is blown toward the heavy-load area during
the air volume adjustment operation than during an operation in
which air is blown uniformly in all directions, thus reducing the
temperature difference between the light- and heavy-load areas with
reliability. This allows for further reducing the temperature
non-uniformity in the space to be air-conditioned and performing
the heating mode of operation even more efficiently.
[0021] The third aspect of the present disclosure easily provides a
configuration for allowing a greater volume of air to be blown
toward the heavy-load area during the air volume adjustment
operation than during an operation in which the air is blown
uniformly in all directions just by adjusting the angle of the
airflow direction adjusting vanes (51). This allows for further
reducing the temperature non-uniformity in the space to be
air-conditioned and performing the heating mode of operation even
more efficiently.
[0022] According to the fourth aspect of the present disclosure,
the horizontal blowing mode may be selected from a plurality of
blowing modes. In addition, selecting the horizontal blowing mode
allows the air volume adjustment operation to be performed if the
load in the heavy-load area has increased to beyond a predetermined
value in the perimeter zone while operation is being performed in
another mode. This reduces the temperature difference between the
light- and heavy-load areas. After that, the operation may be
performed with another mode (e.g., downward blowing mode) selected
instead of the horizontal blowing mode.
[0023] According to the fifth aspect of the present disclosure, the
input device (73) allows the user to indicate whether or not there
is any wall surface (W), thus enabling the air to be blown in only
a direction in which a circulating airflow is produced in the space
to be air-conditioned during the air volume adjustment operation.
This reduces the temperature non-uniformity in the room and
improves the efficiency of operation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a refrigerant circuit diagram for an air
conditioner according to an embodiment of the present
invention.
[0025] FIG. 2 is a perspective view illustrating an indoor unit for
the air conditioner shown in FIG. 1.
[0026] FIG. 3 is a schematic plan view of an indoor unit as viewed
from over the unit with its top panel removed.
[0027] FIG. 4 is a schematic cross-sectional view of the indoor
unit (11) taken along the plane IV-IV shown in FIG. 3.
[0028] FIG. 5 is a schematic bottom view of the indoor unit.
[0029] FIGS. 6A, 6B, and 6C are partial cross-sectional views of
the indoor unit in three different states where an airflow
direction adjusting vane is set at a horizontal blowing position, a
downward blowing position, and a blowing regulated position,
respectively.
[0030] FIG. 7 is a perspective view illustrating an exemplary
arrangement of an indoor unit in a room.
[0031] FIG. 8A is a diagram showing how the indoor unit shown in
FIG. 1 blows the air in four directions in the horizontal blowing
mode, and FIG. 8B is a diagram showing how the indoor unit shown in
FIG. 1 blows the air in two directions in the horizontal blowing
mode.
[0032] FIG. 9 shows the flow of heated air and a temperature
distribution in a vertical cross section of a room subjected to an
airflow control of this embodiment.
[0033] FIG. 10 shows the flow of heated air and a temperature
distribution in a vertical cross section of a room subjected to a
conventional downward blowing operation.
[0034] FIG. 11A shows a temperature distribution in a transverse
cross section of a room subjected to the airflow control of this
embodiment at a constant blowing temperature, and FIG. 11B shows a
temperature distribution in a transverse cross section of a room
subjected to the conventional airflow control at a constant blowing
temperature.
[0035] FIG. 12A shows a temperature distribution in a transverse
cross section of a room subjected to the airflow control of this
embodiment at a constant feed capacity, and FIG. 12B shows a
temperature distribution in a transverse cross section of a room
subjected to the conventional airflow control at a constant feed
capacity.
DESCRIPTION OF EMBODIMENTS
[0036] Embodiments of the present invention will now be described
with reference to the accompanying drawings.
[0037] An embodiment of the present invention is an air conditioner
(1) for cooling and heating indoor air. As illustrated in FIG. 1,
the air conditioner (1) includes an outdoor unit (10) installed
outdoors and an indoor unit (11) installed indoors. The outdoor and
indoor units (10, 11) are connected to each other via two
communication pipes (2, 3), thus forming a refrigerant circuit C in
this air conditioner (1). The refrigerant circuit C circulates a
refrigerant injected therein to perform a vapor compression
refrigeration cycle.
[0038] <Configuration for Refrigerant Circuit>
[0039] In the outdoor unit (10), connected together are a
compressor (12), an outdoor heat exchanger (13), an outdoor
expansion valve (14), and a four-way switching valve (15). The
compressor (12) compresses a low-pressure refrigerant, and
discharges a high-pressure refrigerant thus compressed. In the
compressor (12), a compression mechanism such as a scroll or rotary
compression mechanism is driven by a compressor motor (12a). The
compressor motor (12a) is configured so that the number of
revolutions (i.e., the operation frequency) thereof can be changed
by an inverter.
[0040] The outdoor heat exchanger (13) is a fin-and-tube heat
exchanger. An outdoor fan (16) is installed near the outdoor heat
exchanger (13). In the outdoor heat exchanger (13), the air
transported by the outdoor fan (16) exchanges heat with the
refrigerant. The outdoor fan (16) is configured as a propeller fan
driven by an outdoor fan motor (16a). The outdoor fan motor (16a)
is configured so that the number of revolutions thereof can be
changed by an inverter.
[0041] The outdoor expansion valve (14) is configured as an
electronic expansion valve, of which the degree of opening is
variable. The four-way switching valve (15) includes first to
fourth ports. In the four-way switching valve (15), the first port
is connected to a discharge side of the compressor (12), the second
port is connected to a suction side of the compressor (12), the
third port is connected to a gas-side end portion of the outdoor
heat exchanger (13), and the fourth port is connected to a gas-side
shutoff valve (5). The four-way switching valve (15) is switchable
between a first state (a state indicated by the solid curves in
FIG. 1) and a second state (a state indicated by the broken curves
in FIG. 1). In the four-way switching valve (15) in the first
state, the first port communicates with the third port, and the
second port communicates with the fourth port. In the four-way
switching valve (15) in the second state, the first port
communicates with the fourth port, and the second port communicates
with the third port.
[0042] The two communication pipes are comprised of a liquid
communication pipe (2) and a gas communication pipe (3). The liquid
communication pipe (2) has one end connected to the liquid-side
shutoff valve (4) and the other end connected to a liquid-side end
portion of the indoor heat exchanger (32). The gas communication
pipe (3) has one end connected to the gas-side shutoff valve (5)
and the other end connected to a gas-side end portion of the indoor
heat exchanger (32).
[0043] The indoor unit (11) includes an indoor heat exchanger (32)
and an indoor expansion valve (39). The indoor heat exchanger (32)
is a fin-and-tube heat exchanger. An indoor fan (31) is installed
near the indoor heat exchanger (32). The indoor fan (31) is a
centrifugal blower driven by an indoor fan motor (31a) as will be
described later. The indoor fan motor (31a) is configured so that
the number of revolutions thereof can be changed by an inverter.
The indoor expansion valve (39) is connected to the liquid-side end
portion of the indoor heat exchanger (32) in the refrigerant
circuit C. The indoor expansion valve (39) is configured as an
electronic expansion valve, of which the degree of opening is
variable.
[0044] <Indoor Unit>
[0045] FIGS. 2-5 illustrate an exemplary configuration for the
indoor unit (11). The indoor unit (11) is connected to the outdoor
unit (10) installed outside of an indoor space (R), which is the
space to be air-conditioned, through the communication pipes (2,
3), thereby forming, along with the outdoor unit (10), the air
conditioner (1). The air conditioner (1) performs a cooling mode of
operation and a heating mode of operation in the indoor space (R).
In this example, the indoor unit (11) is configured as a
ceiling-mounted type, and includes an indoor casing (20), an indoor
fan (31), the indoor heat exchanger (32), a drain pan (33), and a
bell mouth (34). The indoor casing (20) is mounted on the ceiling
(U) of the indoor space (R), and is comprised of a casing body (21)
and a decorative panel (22).
[0046] FIG. 2 is a schematic perspective view illustrating the
indoor unit (11) as viewed from obliquely below it. FIG. 3 is a
schematic plan view of the indoor unit (11) as viewed from over the
unit with its top panel (21a) removed. FIG. 4 is a schematic
cross-sectional view of the indoor unit (11) taken along the plane
IV-IV shown in FIG. 3. FIG. 5 is a schematic bottom view of the
indoor unit (11).
[0047] <Casing Body>
[0048] The casing body (21) is arranged so as to be inserted into
an opening cut through the ceiling (U) of the indoor space (R). The
casing body (21) is formed in a generally rectangular
parallelepiped box shape with a bottom opening, and includes a
generally square top panel (21a), and four generally rectangular
side panels (21b) extending downward from the peripheral edges of
the top panel (21a). The casing body (21) houses the indoor fan
(31), the indoor heat exchanger (32), the drain pan (33), and the
bell mouth (34). One (21b) of the four side panels (21b) has a
through hole (H) into which an indoor refrigerant pipe (P) may be
inserted to connect the indoor heat exchanger (32) and the
communication pipes (2, 3) together.
[0049] <Indoor Fan>
[0050] The indoor fan (31) is arranged at the center inside the
casing body (21), and laterally blows the air sucked from under the
casing body (21). In this example, the indoor fan (31) is
configured as a centrifugal blower, and is driven by an indoor fan
motor (31a) arranged at the center of the top panel (21a) of the
casing body (21).
[0051] <Indoor Heat Exchanger>
[0052] The indoor heat exchanger (32) is formed by bending a
refrigerant pipe (a heat transfer tube) so as to surround the
indoor fan (31), and exchanges heat between the refrigerant flowing
through the heat transfer tube (not shown and) provided inside and
the air sucked into the casing body (21). The indoor heat exchanger
(32) may be configured as a fin-and-tube heat exchanger, for
example. Also, the indoor heat exchanger (32) serves as a
refrigerant evaporator to cool the air during the cooling mode of
operation, and serves as a refrigerant condenser (radiator) to heat
the air during the heating mode of operation.
[0053] <Drain Pan>
[0054] The drain pan (33) is formed in a vertically thin, generally
rectangular parallelepiped shape, and is arranged under the indoor
heat exchanger (22). A suction passage (33a) is formed in a center
area of the drain pan (33). The upper surface of the drain pan (33)
has a water-receiving groove (33b). Four first blowing passages
(33c) and four second blowing passages (33d) are further arranged
along the outer periphery of the drain pan (33). The suction
passage (33a) vertically penetrates the drain pan (33). The
water-receiving groove (33b) forms an annular ring surrounding the
suction passage (33a) in a plan view. The four first blowing
passages (33c) respectively extend along the four sides of the
drain pan (33) so as to surround the water-receiving groove (33b)
in a plan view, and vertically penetrate the drain pan (33). The
four second blowing passages (33d) are respectively located at the
four corners of the drain pan (33) in a plan view, and also
vertically penetrate the drain pan (33).
[0055] <Bell Mouth>
[0056] The bell mouth (34) has a cylindrical shape with an opening
area that expands downward from its top toward its bottom. The bell
mouth (34) has its top opening inserted into a suction hole (i.e.,
bottom opening) of the indoor fan (31) and housed in the suction
passage (33a) of the drain pan (33). This configuration guides the
air sucked through the bottom opening of the bell mouth (34) to the
suction hole of the indoor fan (31).
[0057] <Decorative Panel>
[0058] The decorative panel (22) is formed in a vertically thin,
generally rectangular parallelepiped shape. The decorative panel
(22) has a suction port (23) in its center area, and also has a
plurality of air outlets (24, 25) around its outer periphery.
Specifically, the plurality of air outlets (24, 25) includes four
first air outlets (24) and four second air outlets (25). These air
outlets (24, 25) allow the air to be blown in multiple blowing
directions in the horizontal blowing mode.
[0059] The horizontal blowing mode is a mode of operation in which
the air is blown almost horizontally (i.e., at an angle of almost 0
degrees with respect to the horizontal plane) to reach a location
distant from the indoor unit (11) in the room. Note, however, that
in this horizontal blowing mode, the air does not always have to be
blown horizontally but may also be blown slightly obliquely
downward as well.
[0060] <<Suction Port>>
[0061] The suction port (23) vertically penetrates the decorative
panel (22) and communicates with the inner space of the bell mouth
(34). In this example, the suction port (23) is formed in a
generally square shape in a plan view. The suction port (23) is
provided with a suction grille (41) and a suction filter (42). The
suction grille (41) is formed in a generally square shape and has a
lot of through holes in its center area. The suction grille (41) is
mounted onto the suction port (23) of the decorative panel (22) to
cover the suction port (23). The suction filter (42) catches dust
and dirt in the air sucked through the suction grille (41).
[0062] <<Air Outlets>>
[0063] The four first air outlets (24) are straight air outlets
respectively extending linearly along the four sides of the
decorative panel (22) so as to surround the suction port (23) in a
plan view, and vertically penetrate the decorative panel (22) to
communicate with the four first blowing passages (33c) of the drain
pan (33). In this example, the first air outlets (24) are formed in
a generally rectangular shape in a plan view. The four second air
outlets (25) are curved air outlets respectively located at the
four corners of the decorative panel (22) in a plan view, and
vertically penetrate the decorative panel (22) to communicate with
the four second blowing passages (33d) of the drain pan (33).
[0064] <Airflow in Indoor Unit>
[0065] Next, it will be described with reference to FIG. 4 how the
air flows in the indoor unit (11). First, when the indoor fan (31)
starts running, indoor air is sucked from the indoor space (R) into
the indoor fan (31) via the suction grille (41) and suction filter
(42) provided for the suction port (23) of the decorative panel
(22) and the inner space of the bell mouth (34) in this order. The
air sucked into the indoor fan (31) is laterally blown to beside
the indoor fan (31) and exchanges heat with the refrigerant flowing
through the indoor heat exchanger (32) while passing through the
indoor heat exchanger (32). As a result, the air passing through
the indoor heat exchanger (32) is cooled while the indoor heat
exchanger (32) is serving as an evaporator (i.e., during the
cooling mode of operation) and is heated while the indoor heat
exchanger (32) is serving as a condenser (i.e., during the heating
mode of operation). Thereafter, the air that has passed through the
indoor heat exchanger (32) diverges into the four first blowing
passages (33c) and four second blowing passages (33d) of the drain
pan (33) and then is blown into the indoor space (R) through the
four first air outlets (24) and four second air outlets (25) of the
decorative panel (22).
[0066] <Airflow Direction Adjusting Vanes>
[0067] The first air outlets (24) are each provided with an airflow
direction adjusting vane (51) for adjusting the airflow direction
of the air flowing through an associated one of the first blowing
passages (33c) (i.e., the airflow direction of the blowing air).
Each airflow direction adjusting vane (51) is formed in the shape
of a flat plate extending from one longitudinal end of an
associated first air outlet (24) of the decorative panel (22)
through the other end thereof. The airflow direction adjusting vane
(51) is supported by a supporting member (52) on a pivotal axis
(53) extending in the length direction, and is configured to rotate
freely on the pivotal axis (53). The airflow direction adjusting
vane (51) has an arced transverse cross section (i.e., a cross
section taken perpendicularly to the length direction) which
projects outward from the pivotal axis (53) of its rocking
movement. None of the second air outlets (25) are provided with any
airflow direction adjusting vane. However, the second air outlets
(25) may also be provided with such airflow direction adjusting
vanes.
[0068] The airflow direction adjusting vane (51) is a movable vane,
and is configured to change its position from one of the horizontal
blowing position shown in FIG. 6A, the downward blowing position
shown in FIG. 6B, and the blowing regulated position shown in FIG.
6C into another in accordance with settings entered. The horizontal
blowing position is selected in the horizontal blowing mode in
which the air is blown horizontally through the first air outlets
(24). The downward blowing position is selected in a downward
blowing mode in which the air is blown downward through the first
air outlets (24). The blowing regulated position is selected when
blowing the air through the first air outlets (24) is regulated.
Note that airflow direction adjusting vanes optionally provided for
the second air outlets (25) may have substantially the same
configuration, and may operate in almost the same way, as their
counterparts (51) for the first air outlets (24).
[0069] In this embodiment, the horizontal blowing mode is carried
out with the first air outlets (24) selectively used. If airflow
direction adjusting vanes are also provided for the second air
outlets (25), however, the horizontal blowing mode may also be
carried out with both of the first and second air outlets (24, 25)
used.
[0070] In this embodiment, an air volume controller (72) is
included in the operation controller (70) implemented as a control
board as shown in FIG. 1, and controlling the positions of the
airflow direction adjusting vanes (51) via this air volume
controller (72) allows for selecting the horizontal blowing mode
from a plurality of blowing modes. Specifically, the operation
controller (70) allows for selecting either the horizontal blowing
mode to be carried out with the airflow direction adjusting vanes
(51) set at the horizontal blowing position or the downward blowing
mode in which the air is blown toward the floor (F) of the space to
be air-conditioned with the airflow direction adjusting vanes (51)
set at the downward blowing position.
[0071] The airflow direction adjusting vanes (51) provided for the
four first air outlets (24) are controllable by the air volume
controller (72) of the operation controller (70) independently of
each other. If the airflow direction adjusting vane (51) is set at
the blowing regulated position in at least one of the four first
air outlets (24), then the area of the gap between opening edge of
that particular first air outlet (24) and the peripheral edge of
the airflow direction adjusting vane (51) is restricted to be
smaller than the area of a gap at any other first air outlet (24),
thus resulting in greater ventilation resistance. The greater the
ventilation resistance, the less easily the air can be blown
through the first air outlet (24). As a result, the air blown
through the other first air outlets (24) comes to have an increased
airflow velocity and an increased air volume. In addition, the air
blown through the first air outlet (24) where the airflow direction
adjusting vane (51) is set at the blowing regulated position has so
small a volume and so low a velocity that the air is sucked into
the suction port (23) as it is without flowing out into the indoor
space, thus causing a short-circuit there. Note that the blowing
regulated position at which the gap between the opening edge of the
first air outlet (24) and the peripheral edge of the airflow
direction adjusting vane (51) is restricted to a small area is not
limited to the position shown in FIG. 6C but may also be a position
where some ventilation resistance is produced with the angle of the
airflow direction adjusting vane (51) set to be even closer to 0
degrees with respect to the horizontal plane as indicated by the
phantom arrows in FIG. 6A.
[0072] As can be seen, according to this embodiment, the airflow
direction adjusting vanes (51) are used as the air volume adjuster
(50) of the present invention, which is controlled by the air
volume controller (72) of the operation controller (70). In this
embodiment, the airflow direction adjusting vanes (51) are provided
for only the first air outlets (24), not for any of the second air
outlets (25), and therefore, the air volume adjuster (50) is also
provided for only the first air outlets (24). If the airflow
direction adjusting vanes are provided for the second air outlets
(25), the air volume adjuster (50) is provided for the second air
outlets (24) as well.
[0073] In the indoor unit (11) of this embodiment, only a single
casing (20) may be arranged at the center of a room with a square
ceiling (U) or square floor (F) as shown in FIG. 7, for example.
The casing (20) of this indoor unit (11) has four first air outlets
(24) as described above. The casing (20) may allow the air to be
blown uniformly in four directions in the horizontal blowing mode
as shown in FIG. 8A or may allow the air to be blown in only two
mutually opposite directions in the horizontal blowing mode as
shown in FIG. 8B. Although not shown, the air may also be blown in
any two directions other than the ones shown in FIG. 8B or in any
three directions as well. As will be described later, FIG. 8B
illustrates a state of the air volume adjustment operation of the
present invention in which the volume of the air blown toward the
light-load area is set to be smaller than that of the air blown
toward the heavy-load area.
[0074] The indoor unit (11) of this embodiment includes a load
detector (sensor) (71) for detecting a heavy-load area to bear a
relatively heavy air-conditioning load during a heating mode of
operation and a light-load area to bear a lighter air-conditioning
load than the heavy-load area from a perimeter zone in the
perimeter of the indoor space (R) that is the space to be
air-conditioned. The load detector (71) may be provided at a single
point on the lower surface of the decorative panel (22) as shown in
FIG. 2.
[0075] Furthermore, according to this embodiment, the air volume
controller (72) of the operation controller (70) shown in FIG. 1
controls, based on the result of sensing obtained by the load
detector (71), the angle of the airflow direction adjusting vanes
(51) in the horizontal blowing mode, thereby performing an air
volume adjustment operation such that a smaller volume of the air
is blown toward the light-load area than toward the heavy-load
area. In particular, the air volume controller (72) of the
operation controller (70) performs control that allows a greater
volume of the air to be blown toward the heavy-load area during the
air volume adjustment operation in the horizontal blowing mode than
during an operation in which the air is blown uniformly in all
directions.
[0076] --Modes of Operation--
[0077] Next, the modes of operation of the air conditioner (1)
according to this embodiment will be described. The air conditioner
(1) selectively performs either a cooling mode of operation or a
heating mode of operation while switching its modes from one to the
other.
[0078] <Cooling Mode of Operation>
[0079] During the cooling mode of operation, the four-way switching
valve (15) shown in FIG. 1 is switched to the state indicated by
the solid curves to activate the compressor (12), the indoor fan
(31), and the outdoor fan (16). Thus, the refrigerant circuit C
performs a refrigeration cycle in which the outdoor heat exchanger
(13) serves as a condenser and the indoor heat exchanger (32)
serves as an evaporator.
[0080] Specifically, a high-pressure refrigerant compressed by the
compressor (12) flows through the outdoor heat exchanger (13) to
exchange heat with the outdoor air. In the outdoor heat exchanger
(13), the high-pressure refrigerant dissipates its heat into the
outdoor air and condenses. The refrigerant condensed in the outdoor
heat exchanger (13) is then sent to the indoor unit (11), in which
the refrigerant has its pressure reduced by the indoor expansion
valve (39) and then flows through the indoor heat exchanger
(32).
[0081] In the indoor unit (11), the indoor air flows upward through
the suction hole (23) and the inner space of the bell mouth (34) in
this order, and then is sucked into the indoor fan (31). The air is
then blown radially outward from the indoor fan (31). This air
passes through the indoor heat exchanger (32) and exchanges heat
with the refrigerant. In the indoor heat exchanger (32), the
refrigerant absorbs heat from the indoor air and evaporates,
thereby cooling the air.
[0082] The air that has been cooled by the indoor heat exchanger
(32) diverges into the first and second blowing passages (33c,
33d), flows downward, and then is supplied to the indoor space (R)
through the air outlets (24, 25). The refrigerant evaporated in the
indoor heat exchanger (32) is sucked into the compressor (12) and
compressed there again.
[0083] <Heating Mode of Operation>
[0084] During the heating mode of operation, the four-way switching
valve (15) shown in FIG. 1 is switched to the state indicated by
the broken curves to activate the compressor (12), the indoor fan
(31), and the outdoor fan (16). Thus, the refrigerant circuit C
performs a refrigeration cycle in which the indoor heat exchanger
(32) serves as a condenser and the outdoor heat exchanger (13)
serves as an evaporator.
[0085] Specifically, a high-pressure refrigerant compressed by the
compressor (12) flows through the indoor heat exchanger (32) of the
indoor unit (11). In the indoor unit (11), the indoor air flows
upward through the suction hole (23) and the inner space of the
bell mouth (34) in this order, and then is sucked into the indoor
fan (31). The air is then blown radially outward from the indoor
fan (31). This air passes through the indoor heat exchanger (32)
and exchanges heat with the refrigerant. In the indoor heat
exchanger (32), the refrigerant dissipates heat into the indoor air
and condenses, thereby heating the air.
[0086] The air that has been heated by the indoor heat exchanger
(32) diverges into the first and second blowing passages (33c,
33d), flows downward, and then is supplied to the indoor space (R)
through the air outlets (24, 25). The refrigerant condensed in the
indoor heat exchanger (32) has its pressure reduced by the outdoor
expansion valve (14), and then flows through the outdoor heat
exchanger (13), in which the refrigerant absorbs heat from the
outdoor air and evaporates. The refrigerant evaporated from the
outdoor heat exchanger (13) is sucked into the compressor (12) and
compressed there again.
[0087] <Airflow Control During Heating Mode of Operation>
[0088] According to this embodiment, the air volume controller (72)
of the operation controller (70) may perform an air volume
adjustment operation such that a smaller volume of air is blown
toward the light-load area than toward the heavy-load area in the
horizontal blowing mode (see FIG. 8B) during the heating mode of
operation. More particularly, in FIG. 8B, the airflow direction
adjusting vane (51) for the first air outlets (24) through which
the air is blown toward the light-load area is set at the blowing
regulated position, thereby either preventing the air from being
blown toward the light-load area or reducing the volume of the air
blown toward that direction. This allows the heated air to be
supplied preferentially to the heavy-load area in the perimeter
zone.
[0089] In this state, the air will reach the heavy-load area in the
perimeter zone as shown in FIG. 9. Then, the air flows downward
through that heavy-load area, travels toward the center area of the
room, and then rises upward to be sucked into the indoor unit (11).
That is to say, a circulating airflow is produced. In a
conventional general indoor unit, on the other hand, the heated air
is blown downward from the indoor unit (11), and then travels
toward the perimeter zone. However, part of the air starts rising
upward before reaching the perimeter zone as shown in FIG. 10.
Consequently, only a decreased volume of air can reach the
perimeter zone and a circulating airflow is less likely
produced.
[0090] With this regard, performing the airflow control of this
embodiment at a constant blowing temperature allows the indoor
space to be air-conditioned efficiently with the indoor temperature
non-uniformity reduced as shown in FIG. 11A. The conventional
airflow control, on the other hand, tends to result in a larger
degree of indoor temperature non-uniformity and a smaller degree of
air-conditioning efficiency as shown in FIG. 11B compared with the
airflow control of this embodiment. More specifically, according to
FIG. 11A showing the temperature distribution obtained in
two-direction blowing according to this embodiment, the suction
temperature was 22.6.degree. C., the blowing temperature was
40.0.degree. C., and the feed capability was 3.53 kW. On the other
hand, according to FIG. 11B showing the temperature distribution
obtained in four-direction blowing, the suction temperature was
23.3.degree. C., the blowing temperature was 40.0.degree. C., and
the feed capability was 4.49 kW. In FIG. 11A, the indoor space (R)
had an average temperature of 21.8.degree. C. with a standard
deviation of 0.26 K. In FIG. 11B, on the other hand, the indoor
space (R) had an average temperature of 22.5.degree. C. with a
standard deviation of 0.38 K. Note that FIGS. 11A and 11B each show
the temperature distribution measured at 0.6 m over the floor
(F).
[0091] Also, performing the airflow control of this embodiment at a
constant feed capacity allows the indoor space to be
air-conditioned efficiently with the indoor temperature
non-uniformity reduced as shown in FIG. 12A. The conventional
airflow control, on the other hand, tends to result in a larger
degree of indoor temperature non-uniformity and a smaller degree of
air-conditioning efficiency as shown in FIG. 12B compared with the
airflow control of this embodiment. More specifically, according to
FIG. 12A showing the temperature distribution obtained in the
two-direction blowing according to this embodiment, the suction
temperature was 22.6.degree. C., the blowing temperature was
40.0.degree. C., and the feed capability was 3.53 kW. On the other
hand, according to FIG. 12B showing the temperature distribution
obtained in the four-direction blowing, the suction temperature was
21.7.degree. C., the blowing temperature was 34.7.degree. C., and
the feed capability was 3.53 kW. In FIG. 12A, the indoor space (R)
had an average temperature of 21.8.degree. C. with a standard
deviation of 0.26 K. In FIG. 12B, on the other hand, the indoor
space (R) had an average temperature of 21.1.degree. C. with a
standard deviation of 0.31 K. Note that FIGS. 12A and 12B, as well
as FIGS. 11A and 11B, each show the temperature distribution
measured at 0.6 m over the floor (F).
Advantages of this Embodiment
[0092] As can be seen from the foregoing description, according to
this embodiment, the load detector (71) detects a heavy-load area
to bear a relatively heavy air-conditioning load during a heating
mode of operation and a light-load area to bear a lighter
air-conditioning load than the heavy-load area from a perimeter
zone of the indoor space (R). Then, the air volume controller (72)
of the operation controller (70) controls the airflow direction
adjusting vanes (51) in the horizontal blowing mode to perform an
air volume adjustment operation such that a smaller volume of air
is blown toward the light-load area than toward the heavy-load
area. In particular, setting the airflow direction adjusting vanes
(51) at a blowing regulated position during the air volume
adjustment operation makes the volume of the air blown toward the
heavy-load area greater than that of the air blown during the
operation in which the air is blown uniformly in all directions,
thus reducing the difference in temperature between the heavy- and
light-load areas with reliability. This reduces temperature
non-uniformity in the indoor space (R), thus enabling more
efficient heating mode of operation than the conventional one.
[0093] In addition, according to this embodiment, the horizontal
blowing mode or the downward blowing mode may be selected by the
operation controller (70). Thus, when the load in the heavy-load
area has increased to beyond a predetermined value in the perimeter
zone while operation is normally being performed in the downward
blowing mode, the air volume adjustment operation may be performed
in the horizontal blowing mode. This may reduce the temperature
difference between the light- and heavy-load areas. After that, the
operation may be performed in the downward blowing mode again.
Variation of the Embodiment
[0094] In the embodiment described above, the indoor unit (11)
includes the load detector (71) for detecting the perimeter load.
Optionally, the air conditioner may also be configured to include a
means for allowing the user to indicate whether or not there is any
wall surface in perimeter zone, in addition to the load detector
(71). For that purpose, an input device (73) allowing the user to
indicate whether or not there is any wall surface (W) in the
perimeter zone that is the space to be air-conditioned during the
air volume adjustment operation in the horizontal blowing mode may
be provided as shown in FIG. 1. In that case, the air conditioner
may be configured to use a remote controller as the input device to
be connected to the operation controller (70).
[0095] Even with such an alternative configuration adopted, making
the user indicate, through the input device (73), whether or not
there is any wall surface (W) in the heavy-load area also allows
the heated air to be supplied first to the heavy-load area in the
perimeter zone. This allows the air to be blown only in a direction
leading to the wall surface to produce circulating airflow there,
thus reducing the temperature non-uniformity in the indoor space
(R) and efficiently air-conditioning the indoor space (R).
Other Embodiments
[0096] The embodiments described above may be modified as
follows.
[0097] For example, in the embodiments described above, the indoor
unit (11) of the air conditioner (1) is configured as a
ceiling-mounted type to be fitted into the opening (0) of the
ceiling (U). However, the indoor unit (11) may also be a
suspended-type indoor unit to be arranged in the indoor space (R)
by having its casing (20) suspended from the ceiling. Also, the
blowing directions of the indoor unit (11) include at least two
directions toward the heavy- and light-load areas in the perimeter
zone, and therefore, do not have to be four directions or eight
directions exemplified above.
[0098] Furthermore, the embodiment described above is an indoor
unit which may operate in the horizontal blowing mode and the
downward blowing mode. However, these blowing modes are not the
only blowing modes of the indoor unit according to the present
invention. For instance, the present invention is also applicable
to an indoor unit including a blowing mode in which the airflow
direction adjusting vanes (51) swing, as long as that indoor unit
can also operate in the horizontal blowing mode. As the case may
be, the present invention is also applicable to even an indoor unit
configured to operate only in the horizontal blowing mode.
[0099] Furthermore, in the embodiment described above, the airflow
direction adjusting vanes (51) are used as the air volume adjuster
(50). However, as long as air may be supplied in mutually different
volumes toward the heavy- and light-load areas in the horizontal
blowing mode, any members other than the airflow direction
adjusting vanes (51) may also be used as the air volume adjuster
(50).
[0100] Note that the embodiments described above are mere typical
examples in nature, and are not intended to limit the scope,
application, or uses of the present invention.
INDUSTRIAL APPLICABILITY
[0101] As can be seen from the foregoing description, the present
invention is effectively applicable as a technique for controlling
the airflow of a ceiling-mounted air conditioner indoor unit during
its heating mode of operation.
DESCRIPTION OF REFERENCE CHARACTERS
[0102] 1 Air Conditioner [0103] 11 Indoor Unit [0104] 20 Casing
[0105] 24 First Air Outlet [0106] 25 Second Air Outlet [0107] 50
Air Volume Adjuster [0108] 51 Airflow Direction Adjusting Vane
[0109] 70 Operation Controller [0110] 71 Load Detector [0111] 72
Air Volume Controller [0112] 73 Input Device [0113] R Indoor Space
(Space to Be Air-Conditioned) [0114] U Ceiling [0115] W Wall
Surface
* * * * *