AU2018402616B2

AU2018402616B2 - Air conditioner

Info

Publication number: AU2018402616B2
Application number: AU2018402616A
Authority: AU
Inventors: Masakazu Ito
Original assignee: Mitsubishi Heavy Industries Thermal Systems Ltd
Current assignee: Mitsubishi Heavy Industries Thermal Systems Ltd
Priority date: 2018-01-19
Filing date: 2018-11-09
Publication date: 2021-07-08
Anticipated expiration: 2038-11-09
Also published as: EP3739268B1; JP2019124437A; CN111602006A; JP7005355B2; EP3739268A4; EP3739268A1; AU2018402616A1; EP3739268C0; WO2019142466A1; ES2969560T3

Abstract

Provided is an air conditioner in which air blowing noise generated when a discharge air flow strikes fins is reduced without a significant increase in air flow resistance. This air conditioner is provided with: an indoor heat exchanger (18) disposed surrounding the outer periphery of a turbo fan (17); and a plurality of flow conditioning plates (32) mounted on the inner peripheral side of the indoor heat exchanger (18). The indoor heat exchanger (18) has: a plurality of flat surface sections arranged along a flat plane perpendicular to a radial direction at a closest position (P1) which is closest to the turbo fan (17); and a plurality of curved surface sections which connect the plurality of flat surface sections. First flat surface sections (18A) have mounted thereon: a first flow conditioning plate (32A) located at a first predetermined position on the upstream side of the closest position (P1) in the rotational direction (Rd) of the turbo fan (17); and a second flow conditioning plate (32B) located at a second predetermined position on the downstream side of the closest position (P1) in the rotational direction (Rd) of the turbo fan (17), the first and second flow conditioning plates (32A, 32B) being arranged adjacent to each other.

Description

Title of Invention: AIR CONDITIONER

Technical Field

[0001]

The present invention relates to an air conditioner

provided with a plurality of rectifying plates attached to a

heat exchanger on an inner peripheral side.

Background Art

[0002]

The discussion of the background to the invention that

follows is intended to facilitate an understanding of the

invention. However, it should be appreciated that the

discussion is not an acknowledgement or admission that any

aspect of the discussion was part of the common general

knowledge as at the priority date of the application.

[0002a]

In the related art, a ceiling buried-type air conditioner

with a fin tube-shaped heat exchanger provided in the

surroundings of a centrifugal fan is known (see PTL 1, for

example).

The air conditioner disclosed in PTL 1 is adapted such

that three wind guide plates are disposed at each of centers inside four sides of a rectangular heat exchanger. The wind guide plates are formed into a curved shape inclined in a direction opposite to a rotational direction of the centrifugal fan and expanding inward. The air conditioner according to PTL 1 is adapted to cause blowing wind to flow into narrow spaces of the three wind guide plates to change an orientation of the blowing wind to the direction of fins, thereby reducing blowing noise generated by the blowing wind colliding against the fins.

Citation List

Patent Literature

[00031

PTL 1: Japanese Unexamined Patent Application, Publication No.

2001-99436

Summary of Invention

[0004]

However, the air conditioner according to PTL 1 has the

three wind guide plates disposed at each of the centers inside

the four sides of the rectangular heat exchanger. Also, the

wind guide plates are formed into the curved shape inclined in

the direction opposite to the rotational direction of the

centrifugal fan and expanding inward. Thus, disposing the

wind guide plates lead to a significant increase in ventilation resistance.

[00051

The present invention is made in view of such

circumstances, whereby it is desirable to provide an air

conditioner capable of reducing blowing noise generated by

blowing wind colliding against fins without significantly

increasing a ventilation resistance.

[00061

According to a first aspect of the invention there is

provided an air conditioner comprising: a fan that causes air

flowing in along an axial direction of a rotational shaft to

flow out in a radial direction that intersects the axial

direction; a heat exchanger that is disposed so as to surround

an outer periphery of the fan and has a heat transfer pipe and

a plurality of fins attached to the heat transfer pipe; and a

plurality of rectifying plates that is attached to the heat

exchanger on an inner peripheral side, extends along an axial

line that is parallel to the rotational shaft, and linearly

projects toward the rotational shaft, wherein the heat

exchanger has a plurality of planar portions that is disposed

along a plane that perpendicularly intersects the radial

direction at a closest position to the fan, and a plurality of

curved portions that couples the plurality of planar portions,

a first rectifying plate out of the rectifying plates is

attached to at least any of the plurality of planar portions at a first predetermined position on an upstream side in a rotational direction of the fan beyond the closest position while a second rectifying plate out of the rectifying plates is attached thereto at a second predetermined position on a downstream side in the rotational direction of the fan beyond the closest position, the first rectifying plate and the second rectifying plate are disposed to be adjacent to each other, and a first angle formed between the radial direction passing through the closest position of the planar portions and the radial direction passing through a distal end of the first rectifying plate is smaller than a second angle formed between the radial direction passing through the closest position of the planar portions and the radial direction passing through a distal end of the second rectifying plate.

[0007]

According to the air conditioner of an aspect of the

present invention, the first rectifying plate is attached to

at least any one of the plurality of planar portions of the

heat exchanger at the first predetermined position on the

upstream side in the rotational direction of the fan beyond

the closest position to the fan. Thus, a velocity component

of the blowing wind in the rotational direction is reduced due

to turbulence generated by the first rectifying plate before

reaching the closest position, and blowing noise generated by

the blowing wind colliding against fins at the closest

4a

position is reduced.

Also, according to the air conditioner of an aspect of

the present invention, the second rectifying plate is attached

to at least any one of the plurality of planar portions of the

heat exchanger at the second predetermined position on the

downstream side in the rotational direction of the fan beyond

the closest position to the fan. Thus, rising of the velocity component of the blowing wind in the rotational direction again on the downstream side in the rotational direction of the fan beyond the closest position is curbed, and blowing noise generated by the blowing wind colliding against the fins is reduced.

[00081

Further, according to the air conditioner of an aspect of

the present invention, the rectifying plates have a shape

extending along the axial line that is parallel to the

rotational shaft of the fan and linearly projecting toward the

rotational shaft, and a ventilation resistance is thus reduced

as compared with a case in which the rectifying plates are

formed into a curved shape that is inclined in the direction

opposite to the rotational direction of the fan and expands

inward. Also, since the first rectifying plate and the second

rectifying plate are disposed to be adjacent to each other on

the upstream side and the downstream side in the rotational

direction of the fan with the closest position sandwiched

therebetween, a ventilation resistance is reduced as compared

with a case in which three rectifying plates including the

closest position are disposed.

In this manner, according to the air conditioner of the

aspect of the present invention, it is possible to reduce

blowing noise generated by blowing wind colliding against fins

without significantly increasing a ventilation resistance.

[0009]

In the air conditioner according to an aspect of the

present invention, the first predetermined position may be

such a position that an angle formed between the radial

direction passing through the closest position of the planar

portions and the radial direction passing through a distal end

of the first rectifying plate falls within a range of equal to

or greater than 3 degrees and equal to or less than 7 degrees.

More preferably, the first predetermined position may be such

a position that the angle is 5 degrees.

In this manner, it is possible to appropriately reduce a

velocity component of the blowing wind in the rotational

direction at the closest position.

[0010]

In the air conditioner according to an aspect of the

present invention, the second predetermined position may be

such a position that an angle formed between the radial

direction passing through the closest position of the planar

portions and the radial direction passing through a distal end

of the second rectifying plate falls within a range of equal

to or greater than 15 degrees and equal to or less than 20

degrees.

In this manner, it is possible to appropriately curb

rising of the velocity component of the blowing wind in the

rotational direction again on the downstream side in the rotational direction of the fan beyond the closest position.

[0011]

In the air conditioner according to an aspect of the

present invention, in a case in which a distance in the radial

direction between the fan at the closest position of the

planar portions to which the first rectifying plate and the

second rectifying plate are attached and the heat exchanger is

defined as L, and a projecting length of the first rectifying

plate toward the rotational shaft is defined as 1, L/1 3.5

and 1 7 mm may be satisfied.

By setting the distance L between the fan and the heat

exchanger in the radial direction to be equal to or greater

than 3.5 times the projecting length 1 of the first rectifying

plate toward the rotational shaft, it is possible to

sufficiently curb an increase in ventilation resistance due to

the first rectifying plate. By setting 1 to be equal to or

greater than 7 mm, it is possible to cause the first

rectifying plate to appropriately generate turbulence and to

reduce the velocity component of the blowing wind in the

rotational direction at the closest position.

Advantageous Effects of Invention

[0012]

According to the present invention, it is possible to

provide an air conditioner capable of reducing blowing noise generated by blowing wind colliding against fins without significantly increasing a ventilation resistance.

[0012a]

Where any or all of the terms "comprise", "comprises", "comprised" or "comprising" are used in this specification (including the claims) they are to be interpreted as specifying the presence of the stated features, integers, steps or components, but not precluding the presence of one or more other features, integers, steps or components.

Brief Description of Drawings

[0013]

[Figure 1] Figure 1 is a perspective view of an air

conditioner according to an embodiment of the present

invention.

[Figure 2] Figure 2 is a vertical sectional view of an indoor

unit of the air conditioner illustrated in Figure 1.

[Figure 3] Figure 3 is a view of a fan and an indoor heat

exchanger illustrated in Figure 2 when seen from the side of

an opening.

[Figure 4] Figure 4 is a partially enlarged view of the indoor

heat exchanger and a rectifying plate illustrated in Figure 2.

[Figure 5] Figure 5 is a partially enlarged view in the

vicinity of a closest position of a first planar portion

illustrated in Figure 3.

[Figure 6] Figure 6 is a graph illustrating a sound pressure

level of noise generated by the indoor unit.

8a

Description of Embodiments

[00141

Hereinafter, an embodiment of an air conditioner 1

according to the present invention will be described with reference to drawings.

Figure 1 illustrates a perspective view of the ceiling

buried-type air conditioner 1 according to the embodiment, and

Figure 2 illustrates a vertical sectional view thereof. Here,

an example of the ceiling buried-type air conditioner 1 in

which one indoor unit 3 is connected to an outdoor unit 2 is

illustrated.

[0015]

The air conditioner 1 is used with the indoor unit 3

suspended from an indoor ceiling or the like and connected to

the outdoor unit 2 placed outdoor via a refrigerant pipe 4 and

an electric wiring 5. In the outdoor unit 2, machines such as

a refrigerant compressor 6, an outdoor heat exchanger 7, an

outdoor fan 8, a control box 9, and a four-way selector valve,

which is not illustrated, are placed. The outdoor unit 2

configures a refrigerating cycle along with an indoor heat

exchanger 18 provided on the side of the indoor unit 3, which

will be described later, and has a function of adjusting a

refrigerant to be supplied to the indoor unit 3.

[0016]

The indoor unit 3 includes a cabinet 10 with an opened

lower portion and a substantially quadrangular ceiling panel

11 attached to the lower portion of the cabinet 10. At a

lower part inside the cabinet 10, a bellmouth 13 forming an

air suction port 12 and a drain pan 14 are placed, and a part of the drain pan 14 forms an air duct 15. Also, a turbofan 17 driven and rotated by a fan motor 16 is placed at a central part of the ceiling panel of the cabinet 10, and the indoor heat exchanger 18 folded and formed into a quadrangular shape is placed in a secured manner on the ceiling panel side via a bracket, which is not illustrated, so as to surround the outer periphery of the turbofan 17.

[0017]

Inside the cabinet 10, an air passage 19 that guides

indoor air to the turbofan 17 via the bellmouth 13 forming the

air suction port 12 and causes air, the pressure of which has

been raised by the turbofan 17, which has blown out in the

radial direction, to be distributed to the air duct 15 formed

by an inner surface of the cabinet 10 and an outer peripheral

surface of the drain pan 14 through the indoor heat exchanger

18 disposed so as to surround the outer periphery thereof is

configured.

[0018]

The quadrangular ceiling panel 11 is provided with along

rectangular-shaped air outlets 20 from which conditioned wind

blows out along four sides thereof such that the air outlets

communicate with the air duct 15, and the ceiling panel 11

also includes an opening 21 for suctioning the indoor air

provided at the center thereof. The opening 21 is provided

with a suction grille 23 with an air filter 22 and the like placed therein so as to be freely raised and lowered via a wire 24 or the like as illustrated in Figure 1. Also, a wind direction adjustment louver 25 for adjusting a wind direction of the conditioned wind blowing out of the air outlets 20 is placed at each of the air outlets 20 so as to be able to individually swing.

[0019]

The turbofan 17 is configured of a main plate 27

including a hub 26 for securing a rotational shaft 16A of the

fan motor 16 provided at the center, a shroud 29 for forming a

fluid flow path 28 disposed to face the main plate 27, and a

plurality of blades 30 disposed between the shroud 29 and the

main plate 27. The turbofan 17 on the side of the shroud 29

is disposed to face the air suction port 12 of the bellmouth

13, a part of the bellmouth 13 overlaps the inner periphery of

the shroud 29, and a recirculating path 31 is formed

therebetween for circulating a part of the blowing wind of the

turbofan 17 from a gap of the overlapping portion between the

bellmouth 13 and the shroud 29 to the side of an inner surface

29A of the shroud 29 along a rear surface of the bellmouth 13.

[0020]

The turbofan 17 is a fan that rotates about the

rotational shaft 16A of the fan motor 16 and causes air

flowing in along the axial direction of the rotational shaft

16A to flow out in the radial direction that intersects the axial direction of the rotational shaft 16A. Here, the axial direction of the rotational shaft 16A conforms to the vertical direction while the radial direction that intersects the axial direction conforms to the horizontal direction.

[0021]

Here, the indoor heat exchanger 18 will be described with

reference to Figure 3. Figure 3 is a diagram of the turbofan

17 and the indoor heat exchanger 18 illustrated in Figure 2

when seen from the opening 21.

As illustrated in Figure 3, the indoor heat exchanger 18

is disposed to surround the outer periphery of the turbofan 17

and has a heat transfer pipe 18a and a plurality of fins 18b

attached to the heat transfer pipe 18a. As illustrated in

Figure 3, the indoor heat exchanger 18 has a first planar

portion 18A, a second planar portion 18B, a third planar

portion 18C, a fourth planar portion 18D, a fifth planar

portion 18E, a first curved portion 18F, a second curved

portion 18G, a third curved portion 18H, and a fourth curved

portion 181.

[0022]

The first planar portion 18A is a portion disposed along

a plane that perpendicularly intersects the radial direction

at a closest position P1 to the blades 30 of the turbofan 17.

The second planar portion 18B is a portion disposed along a

plane that perpendicularly intersects the radial direction at a closest position P2 to the blades 30 of the turbofan 17.

The third planar portion 18C is a portion disposed along a

plane that perpendicularly intersects the radial direction at

a closest position P3 to the blades 30 of the turbofan 17.

The fourth planar portion 18D is a portion disposed along a

plane that perpendicularly intersects the radial direction at

a closest position P3 to the blades 30 of the turbofan 17.

The fifth planar portion 18E is a portion disposed along a

plane that perpendicularly intersects the radial direction at

a closest position P5 to the blades 30 of the turbofan 17.

[0023]

The first curved portion 18F is a portion that couples

the first planar portion 18A to the second planar portion 18B,

the second curved portion 18G is a portion that couples the

second planar portion 18B to the third planar portion 18C, the

third curved portion 18H is a portion that couples the third

planar portion 18C to the fourth planar portion 18D, and the

fourth curved portion 181 is a portion that couples the fourth

planar portion 18D to the fifth planar portion 18E.

[0024]

Next, a plurality of rectifying plates 32 attached to the

indoor heat exchanger 18 on the inner peripheral side will be

described with reference to Figs. 2 to 5. Figure 4 is a

partially enlarged view of the indoor heat exchanger 18 and

the rectifying plates 32 illustrated in Figure 2. Figure 5 is a partially enlarged view in the vicinity of the closest position P1 of the first planar portion 18A in Figure 3.

As illustrated in Figure 2, a rectifying plate 32

extending along an axial line Xl that is parallel to the

rotational shaft 16A and a rectifying plate 32 extending along

an axial line X2 that is parallel to the rotational shaft 16A

are attached to the indoor heat exchanger 18 on the inner

peripheral side.

[0025]

As illustrated in Figure 3, two rectifying plates 32 are

attached to the first planar portion 18A on the inner

peripheral side, two rectifying plates 32 are attached to the

second planar portion 18B on the inner peripheral side, and

two rectifying plates 32 are attached to the third planar

portion 18C on the inner peripheral side. One rectifying

plate 32 is attached to the fourth planar portion 18D on the

inner peripheral side, and one rectifying plate 32 is attached

to the fifth planar portion 18E on the inner peripheral side.

[0026]

As illustrated in Figure 4, each rectifying plate 32 has

a base portion 32a disposed along a plane that perpendicularly

intersects the radial direction of the turbofan 17, a plate

portion 32b linearly projecting from the base portion 32a

toward the rotational shaft 16A, a pair of holding portions

32c projecting from the base portion 32a in the direction opposite to the plate portion 32b, and a support portion 32d projecting from the base portion 32a in the direction opposite to the plate portion 32b. Each rectifying plate 32 is attached to the indoor heat exchanger 18 by causing the pair of holding portions 32c to hold the heat transfer pipe 18a in a state in which the heat transfer pipe 18a is caused to support the support portion 32d.

[0027]

As illustrated in Figure 4, the upper end of the base

portion 32a of each rectifying plate 32 conforms to the upper

end of each fin 18b of the indoor heat exchanger 18 in a state

in which the rectifying plate 32 is attached to the indoor

heat exchanger 18. With such a positional relationship, an

operator can easily attach the rectifying plate 32 to the

indoor heat exchanger 18 by positioning the rectifying plate

32 such that the upper end of the base portion 32a of the

rectifying plate 32 conforms to the upper end of the fin 18b.

[0028]

As illustrated in Figure 5, a rectifying plate 32A (first

rectifying plate) and a rectifying plate 32B (second

rectifying plate) are attached to the first planar portion 18A

in a state in which the rectifying plate 32A and the

rectifying plate 32B are disposed to be adjacent to each

other. The rectifying plate 32A is attached to a first

predetermined position on the upstream side in a rotational direction Rd of the turbofan 17. Here, the first predetermined position is such a position that an angle 01 formed between the radial direction passing through the closest position P1 of the first planar portion 18A and the radial direction passing through the distal end of the rectifying plate 32A falls within a range of equal to or greater than 3 degrees and equal to or less than 7 degrees.

It is further desirable that the first predetermined position

be such a position that 01 is 5 degrees. In this manner, it

is possible to appropriately reduce a velocity component of

the blowing wind from the turbofan 17 at the closest position

P1 in the rotational direction Rd.

[0029]

The rectifying plate 32B is attached to a second

predetermined position on the downstream side in the

rotational direction Rd of the turbofan 17. Here, the second

predetermined position is such a position that an angle 02

formed between the radial direction passing through the

closest position P1 of the first planar portion 18A and the

radial direction passing through the distal end of the

rectifying plate 32B falls within a range of equal to or

greater than 15 degrees and equal to or less than 20 degrees.

In this manner, it is possible to appropriately curb raising

of the velocity component of the blowing wind in the

rotational direction Rd again on the downstream side in the rotational direction Rd of the turbofan 17 beyond the closest position Pl.

[00301

In Figure 5, the distance L is a distance between the

turbofan 17 at the closest position P1 of the first planar

portion 18A to which the rectifying plate 32A and the

rectifying plate 32B are attached and the indoor heat

exchanger 18 in the radial direction. Also, the distance 1 is

the projecting length of the rectifying plate 32A and the

rectifying plate 32B toward the rotational shaft 16A. In the

present embodiment, the distance L and the distance 1 satisfy

the relationships of Equation (1) and Equation (2) below.

L/1 3.5 (1)

1 7 mm (2)

Equation (1) is a condition for curbing an increase in

ventilation resistance due to the rectifying plate 32A. Also,

Equation (2) is a condition for reducing the velocity

component of the blowing wind from the turbofan 17 in the

rotational direction Rd at the closest position Pl.

[0031]

Note that although the two rectifying plates 32 attached

to the first planar portion 18A have been described above, the

two rectifying plates 32 attached to the second planar portion

18B also have disposition similar to that of the two

rectifying plates 32 attached to the first planar portion 18A.

Also, the two rectifying plates 32 attached to the third

planar portion 18C also have deposition similar to that of the

two rectifying plates 32 attached to the first planar portion

18A.

[0032]

Note that the two rectifying plates 32 are attached to

each of the first planar portion 18A, the second planar

portion 18B, and the third planar portion 18C while one

rectifying plate 32 is attached to each of the fourth planar

portion 18D and the fifth planar portion 18E. This is because

the lengths of the fourth planar portion 18D and the fifth

planar portion 18E are shorter than the lengths of the first

planar portion 18A, the second planar portion 18B, and the

third planar portion 18C, and the amounts of velocity

components of the blowing wind at the closest positions P4 and

P5 in the rotational direction Rd are small.

[0033]

Next, a sound pressure level of noise generated by the

indoor unit 3 of the air conditioner 1 according to the

present embodiment and a comparative example thereof will be

described. Figure 6 is a graph illustrating a sound pressure

level of noise generated by the indoor unit 3 according to the

present embodiment. In Figure 6, the solid line represents a

sound pressure level in a case in which the plurality of

rectifying plates 32 is disposed at the indoor heat exchanger

18 on the inner peripheral side as illustrated in Figure 3

according to the present embodiment, and the dashed line

represents a sound pressure level in a case in which all of

the plurality of rectifying plates 32 illustrated in Figure 3

are not disposed. Figure 6 illustrates a relationship between

a 1/3 octave band center frequency (Hz) and a sound pressure

level (dB).

[0034]

As illustrated in the experiment result in Figure 6, the

air conditioner 1 according to the present embodiment has a

lower sound pressure level in a high frequency region (2 kHz

to 4 kHz) that is likely to be recognized as noise as compared

with the comparative example. The reason for this is

considered to be because the rectifying plates 32 are attached

to the first predetermined position on the upstream side in

the rotational direction Rd of the turbofan 17 beyond the

closest positions P1, P2, and P3 and the velocity component of

the blowing wind in the rotational direction Rd is thus

reduced due to turbulence generated by the rectifying plates

32 before reaching the closest positions P1, P2, and P3.

[0035]

The reason is also considered to be because the

rectifying plates 32 are attached to the second predetermined

position on the downstream side in the rotational direction Rd

of the turbofan 17 beyond the closest positions P1, P2, and P3 to the turbofan 17, and the raising of the velocity component of the blowing wind in the rotational direction Rd again is thus curbed on the downstream side in the rotational direction

Rd of the turbofan 17 beyond the closest positions P1, P2, and

P3.

[00361

Actions and effects achieved by the air conditioner 1

according to the present embodiment described above will be

described.

According to the air conditioner 1 of the present

embodiment, the rectifying plates 32 are attached to the first

predetermined position on the upstream side in the rotational

direction Rd of the turbofan 17 beyond the closest positions

P1, P2, and P3 to the blades 30 of the turbofan 17 at each of

the first planar portion 18A, the second planar portion 18B,

and the third planar portion 18C of the indoor heat exchanger

18. Thus, the velocity component of the blowing wind in the

rotational direction Rd is reduced due to turbulence generated

by the rectifying plates 32 before reaching the closest

positions P1, P2, and P3, and blowing noise generated by the

blowing wind colliding against the fins 18b at the closest

positions P1, P2, and P3 is reduced.

[0037]

Here, the first predetermined position is such a position

that the angle 01 formed between the radial direction passing through the closest position P1 (P2, P3) of the first planar portion 18A (the second planar portion 18B, the third planar portion 18C) and the radial direction passing through the distal end of the rectifying plate 32A falls within a range of equal to or greater than 3 degrees and equal to or less than 7 degrees. More preferably, the first predetermine position is such a position that the angle 01 is 5 degrees.

[00381

Also, according to the air conditioner 1 of the present

embodiment, the rectifying plates 32 are attached to the first

planar portion 18A, the second planar portion 18B, and the

third planar portion 18C of the indoor heat exchanger 18 at

the second predetermine position on the downstream side in the

rotational direction Rd of the turbofan 17 beyond the closest

positions P1, P2, and P3 to the blades 30 of the turbofan 17.

Thus, the raising of the velocity component of the blowing

wind in the rotational direction Rd again is curbed on the

downstream side in the rotational direction Rd of the turbofan

17 beyond the closest positions P1, P2, and P3, and blowing

noise generated by the blowing wind colliding against the fins

18b is thus reduced.

[00391

Here, the second predetermined position is such a

position that the angle 02 formed between the radial direction

passing through the closest position P1 (P2, P3) of the first planar portion 18A (the second planar portion 18B, the third planar portion 18C) and the radial direction passing through the distal end of the rectifying plate 32B falls within a range of equal to or greater than 15 degrees and equal to or less than 20 degrees.

[0040]

Further, according to the air conditioner 1 of the

present embodiment, the rectifying plates 32 have shapes

extending along the axial lines Xl and X2 that are parallel to

the rotational shaft 16A of the turbofan 17 and linearly

projecting toward the rotational shaft 16A, and a ventilation

resistance is thus reduced as compared with a case in which

the rectifying plates 32 are formed into a curved shape

inclined in the direction opposite to the rotational direction

Rd of the turbofan 17 and expanding inward. Also, the two

rectifying plates 32 are disposed to be adjacent to each other

on the upstream side and the downstream side in the rotational

direction Rd of the turbofan 17 with the closest positions P1,

P2, and P3 sandwiched therebetween, and the ventilation

resistance is thus reduced as compared with a case in which

three rectifying plates including the closest positions P1,

P2, and P3 are disposed.

In this manner, according to the air conditioner 1 of the

present embodiment, it is possible to reduce blowing noise

generate by blowing wind colliding against the fins 18b without significantly increasing a ventilation resistance.

[0041]

In the air conditioner 1 according to the present

embodiment, in a case in which the distance between the

turbofan 17 at the closest position P1 (P2, P3) to the first

planar portion 18A (the second planar portion 18B, the third

planar portion 18C) to which the rectifying plate 32A and the

rectifying plate 32B are attached and the indoor heat

exchanger 18 in the radial direction is defined as L, and the

projecting length of the rectifying plate 32A toward the

rotational shaft 16A is defined as 1, L/1 3.5 and 1 7 mm

are satisfied.

[0042]

By setting the distance L between the turbofan 17 and the

indoor heat exchanger 18 in the radial direction to be equal

to or greater than 3.5 times the projecting length 1 of the

rectifying plate 32A and the rectifying plate 32B toward the

rotational shaft 16A, it is possible to sufficiently curb an

increase in ventilation resistance due to the rectifying plate

32A and the rectifying plate 32B. By setting 1 to be equal to

or greater than 7 mm, it is possible to cause the rectifying

plate 32A to appropriately generate turbulence and to reduce

the velocity component of the blowing wind in the rotational

direction Rd at the closest position P1 (P2, P3).

Reference Signs List

[00431

1 Air conditioner

2 Outdoor unit

3 Indoor unit

4 Refrigerant pipe

Electric wiring

6 Refrigerant compressor

7 Outdoor heat exchanger

8 Outdoor fan

9 Control box

Cabinet

11 Ceiling panel

12 Air suction port

13 Bellmouth

14 Drain pan

Air duct

16 Fan motor

16A Rotational shaft

17 Turbofan

18 Indoor heat exchanger

18a Heat transfer pipe

18b Fin

18A First planar portion

18B Second planar portion

18C Third planar portion

18D Fourth planar portion

18E Fifth planar portion

18F First curved portion

18G Second curved portion

18H Third curved portion

181 Fourth curved portion

19 Air passage

Air outlet

21 Opening

22 Air filter

23 Suction grille

24 Wire

Wind direction adjustment louver

26 Hub

27 Main plate

28 Fluid flow path

29 Shroud

Blade

31 Recirculating path

32, 32A, 32B Rectifying plate

32a Base portion

32b Plate portion

Claims

The claims defining the invention are as follows:

[Claim 1]

An air conditioner comprising:

a fan that causes air flowing in along an axial direction

of a rotational shaft to flow out in a radial direction that

intersects the axial direction;

a heat exchanger that is disposed so as to surround an

outer periphery of the fan and has a heat transfer pipe and a

plurality of fins attached to the heat transfer pipe; and

a plurality of rectifying plates that is attached to the

heat exchanger on an inner peripheral side, extends along an

axial line that is parallel to the rotational shaft, and

linearly projects toward the rotational shaft,

wherein the heat exchanger has

a plurality of planar portions that is disposed

along a plane that perpendicularly intersects the radial

direction at a closest position to the fan, and

a plurality of curved portions that couples the

plurality of planar portions,

a first rectifying plate out of the rectifying plates is

attached to at least any of the plurality of planar portions

at a first predetermined position on an upstream side in a

rotational direction of the fan beyond the closest position

while a second rectifying plate out of the rectifying plates

is attached thereto at a second predetermined position on a downstream side in the rotational direction of the fan beyond the closest position, the first rectifying plate and the second rectifying plate are disposed to be adjacent to each other, and a first angle formed between the radial direction passing through the closest position of the planar portions and the radial direction passing through a distal end of the first rectifying plate is smaller than a second angle formed between the radial direction passing through the closest position of the planar portions and the radial direction passing through a distal end of the second rectifying plate.
[Claim 2]

The air conditioner according to claim 1, wherein the

first predetermined position is such a position that the first

angle falls within a range of equal to or greater than 3

degrees and equal to or less than 7 degrees.
[Claim 3]

The air conditioner according to claim 2, wherein the

first predetermined position is such a position that the first

angle is 5 degrees.
[Claim 4]

The air conditioner according to any one of claims 1 to

3, wherein the second predetermined position is such a

position that the second angle falls within a range of equal

to or greater than 15 degrees and equal to or less than 20 degrees.
[Claim 5]

The air conditioner according to any one of claims 1 to

4, wherein in a case in which a distance in the radial

direction between the fan at the closest position of the

planar portions to which the first rectifying plate and the

second rectifying plate are attached and the heat exchanger is

defined as L, and a projecting length of the first rectifying

plate toward the rotational shaft is defined as 1, L/1 3.5

and 1 7 mm are satisfied.