U.S. patent application number 17/154478 was filed with the patent office on 2021-08-05 for ceiling-embedded air conditioner.
The applicant listed for this patent is MITSUBISHI HEAVY INDUSTRIES, LTD.. Invention is credited to Chihiro MYOREN, Takanori SHIBATA, Ken SHIMIZU.
Application Number | 20210239329 17/154478 |
Document ID | / |
Family ID | 1000005361425 |
Filed Date | 2021-08-05 |
United States Patent
Application |
20210239329 |
Kind Code |
A1 |
MYOREN; Chihiro ; et
al. |
August 5, 2021 |
CEILING-EMBEDDED AIR CONDITIONER
Abstract
A ceiling-embedded air conditioner includes, a casing, a motor
including an output shaft protruding downward, the output shaft
being driven to rotate about an axis, a main plate fixed to the
output shaft and extending radially outward, a turbofan including
an impeller, a heat exchanger passed through by air that is sent
from the turbofan. And the main plate includes, a tapered portion,
a recess formed to be recessed radially inward from the tapered
portion, the recess being defined by a cylindrical plate portion
extending along the axis, and a disk plate portion extending
radially outward from the upper end of the cylindrical plate
portion. And an opening is formed in the cylindrical plate portion,
the opening penetrates the cylindrical plate portion in the radial
direction, and configured such that a circulation flow that exits
from the impeller and flows around above the main plate passes
through the opening.
Inventors: |
MYOREN; Chihiro; (Tokyo,
JP) ; SHIBATA; Takanori; (Tokyo, JP) ;
SHIMIZU; Ken; (Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MITSUBISHI HEAVY INDUSTRIES, LTD. |
Tokyo |
|
JP |
|
|
Family ID: |
1000005361425 |
Appl. No.: |
17/154478 |
Filed: |
January 21, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F24F 1/0047 20190201;
F24F 1/0022 20130101; F24F 1/0011 20130101; F24F 1/0063
20190201 |
International
Class: |
F24F 1/0047 20060101
F24F001/0047; F24F 1/0022 20060101 F24F001/0022; F24F 1/0011
20060101 F24F001/0011; F24F 1/0063 20060101 F24F001/0063 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 31, 2020 |
JP |
2020-015374 |
Claims
1. A ceiling-embedded air conditioner, comprising: a casing
including a suction port formed in the center of a lower portion of
the casing and an outlet port formed around the suction port; a
motor provided in the casing and including an output shaft
protruding downward, the output shaft being driven to rotate about
an axis extending in a vertical direction; a main plate fixed to
the output shaft in the casing and extending radially outward of
the axis; a turbofan including an impeller attached to a lower
surface of the main plate in the casing at intervals in a
circumferential direction, the impeller being configured to send
air introduced from the suction port radially outward; and a heat
exchanger provided to surround the turbofan in the casing and
passed through by air that is sent from the turbofan and flows
toward the outlet port, wherein the main plate includes a tapered
portion extending to increase in diameter radially outward as
advancing upward, and a recess formed to be recessed radially
inward from the tapered portion over the circumferential direction,
the recess being defined by a cylindrical plate portion extending
along the axis and a disk plate portion extending radially outward
from the upper end of the cylindrical plate portion, and an opening
is formed in the cylindrical plate portion, the opening penetrating
the cylindrical plate portion in the radial direction, and
configured such that a circulation flow that exits from the
impeller and flows around above the main plate passes through the
opening.
2. The ceiling-embedded air conditioner according to claim 1,
wherein a plurality of the openings are arranged in the
circumferential direction, and the circumferential end portions of
the plurality of the openings adjacent to each other overlap in the
vertical direction.
3. The ceiling-embedded air conditioner according to claim 1,
wherein each of the plurality of the openings has a rectangular
shape, the longitudinal direction of the rectangular shape is in
the circumferential direction, and the positions of the plurality
of the openings adjacent to each other in the vertical direction
are different from each other.
4. The ceiling-embedded air conditioner according to claim 2,
wherein each of the plurality of the openings has a rectangular
shape, the longitudinal direction of the rectangular shape is in
the circumferential direction, and the positions of the plurality
of the openings adjacent to each other in the vertical direction
are different from each other.
5. The ceiling-embedded air conditioner according to claim 1,
wherein end edges of the plurality of the openings in the
circumferential direction extend in a direction inclined with
respect to the axis, and the end edges of the plurality of the
openings adjacent to each other overlap in the vertical
direction.
6. The ceiling-embedded air conditioner according to claim 2,
wherein end edges of the plurality of the openings in the
circumferential direction extend in a direction inclined with
respect to the axis, and the end edges of the plurality of the
openings adjacent to each other overlap in the vertical
direction.
7. The ceiling-embedded air conditioner according to claim 1,
wherein the plurality of the openings are arranged at intervals in
the circumferential direction to form a row, a plurality of rows
are arranged at intervals in the vertical direction, and positions
of the plurality of the openings in the circumferential direction
are different between the plurality of rows adjacent in the
vertical direction.
8. The ceiling-embedded air conditioner according to claim 2,
wherein the plurality of the openings are arranged at intervals in
the circumferential direction to form a row, a plurality of rows
are arranged at intervals in the vertical direction, and positions
of the plurality of the openings in the circumferential direction
are different between the plurality of rows adjacent in the
vertical direction.
9. The ceiling-embedded air conditioner according to claim 3,
wherein the plurality of the openings are arranged at intervals in
the circumferential direction to form a row, a plurality of rows
are arranged at intervals in the vertical direction, and positions
of the plurality of the openings in the circumferential direction
are different between the plurality of rows adjacent in the
vertical direction.
10. The ceiling-embedded air conditioner according to claim 4,
wherein the plurality of the openings are arranged at intervals in
the circumferential direction to form a row, a plurality of rows
are arranged at intervals in the vertical direction, and positions
of the plurality of the openings in the circumferential direction
are different between the plurality of rows adjacent in the
vertical direction.
11. The ceiling-embedded air conditioner according to claim 5,
wherein the plurality of the openings are arranged at intervals in
the circumferential direction to form a row, a plurality of rows
are arranged at intervals in the vertical direction, and positions
of the plurality of the openings in the circumferential direction
are different between the plurality of rows adjacent in the
vertical direction.
12. The ceiling-embedded air conditioner according to claim 6,
wherein the plurality of the openings are arranged at intervals in
the circumferential direction to form a row, a plurality of rows
are arranged at intervals in the vertical direction, and positions
of the plurality of the openings in the circumferential direction
are different between the plurality of rows adjacent in the
vertical direction.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority to Japanese
Patent Application Number 2020-015374 filed on Jan. 31, 2020. The
entire contents of the above-identified application are hereby
incorporated by reference.
TECHNICAL FIELD
[0002] The disclosure relates to a ceiling-embedded air
conditioner.
RELATED ART
[0003] As an example of an air conditioner, a ceiling-embedded air
conditioner is widely used. The ceiling-embedded air conditioner
mainly includes a casing embedded in an indoor ceiling, a motor
including an output shaft that rotates about an axis extending in a
vertical direction, a turbofan, a main plate that fixes the
turbofan to the output shaft, and a heat exchanger that surrounds
the turbofan. By the rotation of the turbofan, indoor air is taken
in from the central portion of the casing, and is supplied indoors
as cold air or warm air by passing through the heat exchanger.
[0004] As a specific example of such a ceiling-embedded air
conditioner, the one described in Japanese Patent Application
Laid-Open No. 2000-227231 is known. In this apparatus, the main
plate has a conical shape whose diameter increases radially outward
as advancing from the lower side to the upper side. Most of the air
taken into the casing flows upward along the outer surface of the
main plate and is then sent to the radially outer heat exchanger by
the turbofan. On the other hand, a part of the air taken into the
casing forms a circulation flow that goes around the turbofan from
above and flows into the upper side of the main plate. In the
apparatus described in Japanese Patent Application Laid-Open No.
2000-227231, this circulation flow is used as air for cooling the
motor. The air that has cooled the motor joins the main flow (i.e.,
the flow along the outer surface of the main plate) again through
the opening formed in the main plate.
[0005] Here, in the case where the angle at which the main flow and
the circulation flow is close to a right angle, a mixing loss
occurs between the main flow and the circulation flow. As a result,
the performance of the air conditioner may be affected. Therefore,
in the apparatus according to Japanese Patent Application Laid-Open
No. 2000-227231, a bulging portion for guiding the flow direction
of the circulation flow is additionally provided as a new component
in the opening of the main plate.
SUMMARY
[0006] However, the attachment of the separate component to the
main plate as described above leads to a complicated configuration
and an increase in the number of components and the number of
manufacturing steps. As a result, the manufacturing cost may
increase.
[0007] The present disclosure has been made to solve the above
problems, and an object of the present disclosure is to provide a
ceiling-embedded air conditioner having a simpler configuration and
further improved performance.
[0008] In order to solve the problems described above, there is
provided a ceiling-embedded air conditioner including, a casing
including a suction port formed in the center of a lower portion of
the casing and an outlet port formed around the suction port, a
motor provided in the casing and including an output shaft
protruding downward, the output shaft being driven to rotate about
an axis extending in a vertical direction, a main plate fixed to
the output shaft in the casing and extending radially outward of
the axis; a turbofan including an impeller attached to a lower
surface of the main plate in the casing at intervals in a
circumferential direction, the impeller being configured to send
air introduced from the suction port radially outward, a heat
exchanger provided to surround the turbofan in the casing and
passed through by air that is sent from the turbofan and flows
toward the outlet port. And the main plate includes, a tapered
portion extending to increase in diameter radially outward as
advancing upward, a recess formed to be recessed radially inward
from the tapered portion over the circumferential direction, the
recess being defined by a cylindrical plate portion extending along
the axis, and a disk plate portion extending radially outward from
the upper end of the cylindrical plate portion. And an opening is
formed in the cylindrical plate portion, the opening penetrating
the cylindrical plate portion, and configured such that a
circulation flow that exits from the impeller and flows around
above the main plate passes through the opening.
[0009] According to the present disclosure, it is possible to
provide a ceiling-embedded air conditioner having a simpler
configuration and further improved performance.
BRIEF DESCRIPTION OF DRAWINGS
[0010] The disclosure will be described with reference to the
accompanying drawings, wherein like numbers reference like
elements.
[0011] FIG. 1 is a cross-sectional view illustrating a
configuration of a ceiling-embedded air conditioner according to an
embodiment of the present disclosure.
[0012] FIG. 2 is a cross-sectional view illustrating a
configuration of a main plate according to an embodiment of the
present disclosure.
[0013] FIG. 3 is a side view illustrating a configuration of an
opening according to an embodiment of the present disclosure.
[0014] FIG. 4 is a side view illustrating a modified example of an
opening according to an embodiment of the present disclosure.
[0015] FIG. 5 is a side view illustrating another modified example
of an opening according to an embodiment of the present
disclosure.
[0016] FIG. 6 is a side view illustrating a further modified
example of an opening according to an embodiment of the present
disclosure.
DESCRIPTION OF EMBODIMENTS
First Embodiment
Configuration of Ceiling-embedded Air Conditioner
[0017] Hereinafter, a ceiling-embedded air conditioner 100
according to a first embodiment of the present disclosure will be
described with reference to FIGS. 1 to 3. As illustrated in FIG. 1,
the ceiling-embedded air conditioner 100 includes a casing 1, a
motor 2, a main plate 3, a turbofan 4, a heat exchanger 5, and a
bell mouth 6.
[0018] The casing 1 is embedded in a ceiling wall C of a building.
The casing 1 has a rectangular shape when viewed from below, and is
recessed upward to form a space therein. To be specific, the casing
1 includes a panel 1A exposed to the ceiling surface Ca and a
box-shaped cabinet 1B provided above the panel 1A. The panel 1A
includes a panel body 11, which is a rectangular frame body, and a
grill 12, which is a suction port 11A provided at the center of the
lower portion. The panel body 11 forms an outlet port 11B around
the suction port 11A.
[0019] The motor 2 is provided at a central portion of a bottom
surface 1S facing downward inside the cabinet 1B. The motor 2
includes a motor body 21 that accommodates a coil, a magnet, or the
like, and an output shaft 22 that protrudes vertically downward
from the motor body 21. The output shaft 22 is rotationally driven
about an axis Ac extending in the vertical direction.
[0020] A main plate 3 extending radially outward from the output
shaft 22 is fixed to the output shaft 22. The configuration of the
main plate 3 will be described later. A turbofan 4 is attached to a
lower surface of the main plate 3. The turbofan 4 includes an
impeller 41 including a plurality of blades arranged at intervals
in a circumferential direction, and a disk-shaped shroud 42
covering the impeller 41 from below. The main plate 3 and the
turbofan 4 rotate with the rotation of the output shaft 22, and the
air sucked from the suction port 11A is sent outward radially.
[0021] An annular heat exchanger 5 surrounding the turbofan 4 is
provided radially outside the turbofan 4. The heat exchanger 5 is a
part of a refrigerant circuit having a refrigeration cycle. The air
(main flow Fm) sent to the heat exchanger 5 by the turbofan 4
exchanges heat with the refrigerant when passing through the heat
exchanger 5. Thus, the air flowing out to the outer circumferential
side of the heat exchanger 5 becomes cold air or warm air. The air
flows downward along the side surface of the cabinet 1B and is
supplied into the room from the outlet port 11B.
[0022] A bell mouth 6 fixed to an upper portion of the panel body
11 is disposed below the turbofan 4. The bell mouth 6 is provided
to guide the air introduced from the suction port 11A and send the
air to the turbofan 4. The bell mouth 6 has a conical shape in
which the diameter gradually decreases from the lower side toward
the upper side.
Configuration of Main Plate
[0023] Next, the configuration of the main plate 3 will be
described in detail with reference to FIGS. 2 and 3. As illustrated
in FIG. 2, the main plate 3 includes a bottom plate portion 31, a
lower tapered portion 32, a cylindrical plate portion 33, a disk
plate portion 34, an upper tapered portion 35, and an upper plate
portion 36, which are integrally connected in this order from the
inside to the outside radially.
[0024] The bottom plate portion 31 has a circular shape extending
radially outward from the outer circumferential surface of the
output shaft 22. A lower tapered portion 32 is connected to an
outer circumferential edge of the bottom plate portion 31. The
lower tapered portion 32, from the lower side to the upper side,
extends radially from the inner side to the outer side as advancing
from the lower side to the upper side. That is, the lower tapered
portion 32 has a conical shape whose diameter gradually increases
as advancing upward. An outer circumferential edge of the lower
tapered portion 32 is located below the motor body 21.
[0025] A cylindrical plate portion 33 is connected to an outer
circumferential edge of the lower tapered portion 32. The
cylindrical plate portion 33 has a cylindrical shape centered on
the axis Ac. That is, the cylindrical plate portion 33 extends
along the axis Ac in a cross-sectional view. The cylindrical plate
portion 33 is formed with a plurality of openings h penetrating the
cylindrical plate portion 33 in the radial direction. As
illustrated in FIG. 3, the plurality of openings h are rectangular
and are arranged at intervals in the circumferential direction. As
illustrated in FIG. 2, the openings h are each formed at a position
corresponding to the lower end of the motor body 21 in the vertical
direction.
[0026] A disk plate portion 34 is connected to an upper end edge of
the cylindrical plate portion 33. The disk plate portion 34 extends
radially outward from the upper end of the cylindrical plate
portion 33. The disk plate portion 34 has an annular shape centered
on the axis Ac. The cylindrical plate portion 33 and the disk plate
portion 34 intersect at a right angle in a cross-sectional view
including the axis Ac. Here, the term "right angle" refers to a
substantially right angle, and a design tolerance and a
manufacturing error are included in the term "right angle". That
is, it is possible to adopt a configuration in which the
cylindrical plate portion 33 and the disk plate portion 34
intersect with each other at a slight obtuse angle. The recess R is
defined by the cylindrical plate portion 33 and the disk plate
portion 34.
[0027] An upper tapered portion 35 is connected to an outer
circumferential edge of the disk plate portion 34. Similarly to the
lower tapered portion 32, the upper tapered portion 35 extends
radially from the inner side to the outer side as advancing from
the lower side to the upper side That is, the lower tapered portion
32 has a conical shape whose diameter gradually increases as
advancing upward. Preferably, the lower tapered portion 32 and the
upper tapered portion 35 are on the same conical surface. An upper
plate portion 36 is connected to an outer circumferential edge of
the upper tapered portion 35. The upper plate portion 36 has an
annular shape extending radially outward from an outer
circumferential edge of the upper tapered portion 35. The impeller
41 of the turbofan 4 described above is attached to the lower
surfaces of the upper plate portion 36 and the upper tapered
portion 35. Note that in FIG. 2, an illustration of the impeller 41
is omitted.
Operational Effects
[0028] Next, the operation of the ceiling-embedded air conditioner
100 will be described. To operate the ceiling-embedded air
conditioner 100, the motor 2 is first driven. By driving the motor
2, the output shaft 22, the main plate 3, and the turbofan 4 rotate
about the axis Ac. As the turbofan 4 rotates, indoor air is taken
in through the suction port 11A. The air is sent to the turbofan 4
through the bell mouth 6, and then is pressure-fed radially outward
to form a main flow Fm (see FIG. 1 or 2). The main flow Fm flows
along the lower surface of the main plate 3. That is, the main flow
Fm flows from the inside to the outside radially as advancing from
the lower side to the upper side. Most of the main flow Fm
exchanges heat with the refrigerant by passing through the heat
exchanger 5, and becomes cold air or warm air to be supplied into
the room from the outlet port 11B.
[0029] On the other hand, a part of the main flow Fm does not flow
toward the heat exchanger 5, but flows to go around above the main
plate 3, thereby forming a circulation flow Fc. The circulation
flow Fc flows toward the inner circumferential side along the upper
surface of the main plate 3, and then cool s the motor body 21 by
being blown to the motor body 21. The circulation flow Fc that has
cooled the motor body 21 flows downward, and then joins the main
flow Fm on the lower surface side of the main plate 3 through the
openings h formed in the main plate 3.
[0030] Here, when the angle at which the main flow Fm and the
circulation flow Fc join is close to a right angle, a mixing loss
occurs between the main flow Fm and the circulation flow Fc. As a
result, the air does not flow smoothly in the casing 1, which may
affect the performance of the air conditioner. Therefore, in the
present embodiment, the recess R is formed in the main plate 3, and
the openings h are formed in the cylindrical plate portion 33 that
defines the recess R.
[0031] According to the above configuration, the cylindrical plate
portion 33 in which the openings h are formed extends along the
axis Ac. Thus, the circulation flow Fc is blown radially outward
from the openings h. Here, the main flow Fm flows upward as
advancing radially outward. Since the circulation flow Fc is blown
radially outward, the angle at which the main flow Fm and the
circulation flow Fc join together can be reduced. As a result, the
mixing loss generated between the main flow Fm and the circulation
flow Fc can be reduced. Further, in the above-described
configuration, such a reduction in mixing loss can be realized only
by forming the recess R in the main plate 3 without increasing the
number of components. This makes it possible to improve the
performance of the ceiling-embedded air conditioner 100 while
suppressing an increase in manufacturing cost.
Other Embodiments
[0032] The embodiments of the present disclosure have been
described above. Various changes and modifications can be made to
the above configuration without departing from the scope of the
present disclosure. For example, in the above-described embodiment,
an example in which the openings h are rectangular and are arranged
at intervals in the circumferential direction has been described.
However, it is also possible to adopt the configurations
illustrated in FIGS. 4 to 6.
[0033] In the example of FIG. 4, the positions of the openings h2
adjacent to each other in the axis Ac direction are different.
Further, the circumferential end portions t1 of the openings h2
overlap each other in the vertical direction.
[0034] According to the above configuration, the circulation flow
Fc can be guided uniformly over the entire region in the
circumferential direction. As a result, the pressure loss at the
openings h2 can be further reduced. In addition, the above
configuration can make it possible to suppress a decrease in
strength of the main plate due to the formation of the plurality of
openings h2. As a result, the durability of the ceiling-embedded
air conditioner 100 can be further improved.
[0035] In the example of FIG. 5, the end edges L1 of the openings
h3 in the circumferential direction extend in a direction inclined
with respect to the axis Ac, and the end edges L1 of the openings
h3 adjacent to each other overlap in the vertical direction. With
this configuration, the same operational effects as those of the
example of FIG. 4 can be obtained.
[0036] In the example of FIG. 6, a plurality of openings h4 are
arranged at intervals in the circumferential direction to form a
row, and a plurality of (two) rows R1 and R2 are provided at
intervals in the vertical direction. The positions of the openings
h4 in the circumferential direction are different from each other
in rows adjacent to each other in the vertical direction. With this
configuration as well, it is possible to obtain the same
operational effects as those of the examples of FIGS. 4 and 5.
Notes
[0037] The ceiling-embedded air conditioner 100 described in each
of the embodiments is grasped as follows, for example.
[0038] (1) A ceiling-embedded air conditioner 100 according to a
first aspect includes, a casing 1 including a suction port 11A
formed in the center of a lower portion of the casing 1 and an
outlet port 11B formed around the suction port 11A, a motor 2
provided in the casing 1 and including an output shaft 22
protruding downward, the output shaft 22 being driven to rotate
about an axis Ac extending in a vertical direction, a main plate 3
fixed to the output shaft 22 in the casing 1 and extending radially
outward of the axis Ac, a turbofan 4 including an impeller 41
attached to a lower surface of the main plate 3 in the casing 1 at
intervals in a circumferential direction, the impeller 41 being
configured to send air introduced from the suction port 11A
radially outward, a heat exchanger 5 provided to surround the
turbofan 4 in the casing 1, and passed through by air that is sent
from the turbofan 4 and flows toward the outlet port 11B. And the
main plate 3 includes, a tapered portion 32 and 35 extending to
increase in diameter radially outward as advancing upward, and a
recess R formed to be recessed radially inward from the tapered
portion 32 and 35 over the circumferential direction, the recess R
being defined by a cylindrical plate portion 33 extending along the
axis Ac and a disk plate portion 34 extending radially outward from
the upper end of the cylindrical plate portion 33. And an opening h
is formed in the cylindrical plate portion 33, the opening h
penetrating the cylindrical plate portion 33 in the radial
direction, and configured such that a circulation flow Fc that
exits from the impeller 41 and flows around above the main plate 3
passes through the opening.
[0039] According to the above configuration, the cylindrical plate
portion 33 in which the opening h is formed extends along the axis
Ac. Thus, the circulation flow Fc is blown radially outward from
the opening h. Here, a main flow Fm flowing upward along the main
plate 3 is formed outside the main plate 3. More specifically, the
main flow Fm flows upward as advancing radially outward. Since the
circulation flow Fc blows out radially outward as described above,
the angle at which the main flow Fm and the circulation flow Fc
join together can be reduced. As a result, the mixing loss
generated between the main flow Fm and the circulation flow Fc can
be reduced. Further, in the above-described configuration, such a
reduction in mixing loss can be realized only by forming the recess
R in the main plate 3 without increasing the number of components.
This makes it possible to improve the performance of the
ceiling-embedded air conditioner 100 while suppressing an increase
in manufacturing cost.
[0040] (2) In the ceiling-embedded air conditioner 100 according to
a second aspect, a plurality of openings h2 are arranged in the
circumferential direction, and the circumferential end portions t1
of the openings h2 adjacent to each other overlap in the vertical
direction.
[0041] According to the above configuration, the plurality of
openings h2 are arranged in the circumferential direction, and the
circumferential end portions t1 of the adjacent openings h2 overlap
in the vertical direction. Thus, the circulation flow can be guided
uniformly over the entire region in the circumferential direction.
As a result, the pressure loss at the openings h2 can be further
reduced.
[0042] (3) In the ceiling-embedded air conditioner 100 according to
the third aspect, each of the openings h2 has a rectangular shape,
the longitudinal direction of the rectangular shape is in the
circumferential direction, and the positions of the openings h2
adjacent to each other in the vertical direction are different from
each other.
[0043] According to the above configuration, each of the openings
h2 has a rectangular shape, and the positions of the adjacent
openings h2 in the vertical direction are different from each
other. Accordingly, the circulation flow Fc can be guided uniformly
over the entire region in the circumferential direction, and a
decrease in strength of the main plate 3 due to the formation of
the plurality of openings h2 can be suppressed to be small. As a
result, the durability of the ceiling-embedded air conditioner 100
can be further improved.
[0044] (4) In the ceiling-embedded air conditioner 100 according to
a fourth aspect, the end edge L1 in the circumferential direction
of each of the openings h3 extends in a direction inclined with
respect to the axis Ac, and the end edges L1 of the openings h3
adjacent to each other overlap in the vertical direction.
[0045] According to the above configuration, the end edge L1 of
each of the openings h3 in the circumferential direction is
inclined, and the adjacent end edges L1 overlap each other in the
vertical direction. Thus, the circulation flow Fc can be uniformly
guided over the entire region in the circumferential direction.
[0046] (5) In the ceiling-embedded air conditioner 100 according to
a fifth aspect, the plurality of openings h4 are arranged at
intervals in the circumferential direction to form rows R1 and R2,
the plurality of rows such as R1 and R2 are arranged at intervals
in the vertical direction, and the positions of the plurality of
openings h4 in the circumferential direction are different between
the rows R1 and R2 adjacent in the vertical direction.
[0047] According to the above configuration, the plurality of
openings h4 are arranged in the circumferential direction and the
vertical direction, and the positions of the openings h4 in the
circumferential direction are different between the rows R1 and R2
adjacent to each other in the vertical direction. Accordingly, the
circulation flow Fc can be guided over the entire region in the
circumferential direction uniformly, and a decrease in strength of
the main plate 3 due to the formation of the plurality of openings
h4 can be suppressed to be small. As a result, the durability of
the ceiling-embedded air conditioner 100 can be further
improved.
[0048] While preferred embodiments of the invention have been
described as above, it is to be understood that variations and
modifications will be apparent to those skilled in the art without
departing from the scope and spirits of the invention. The scope of
the invention, therefore, is to be determined solely by the
following claims.
* * * * *