U.S. patent application number 14/145180 was filed with the patent office on 2014-10-23 for turbo fan.
This patent application is currently assigned to LG Electronics Inc.. The applicant listed for this patent is LG Electronics Inc.. Invention is credited to Namjoon Cho, Youngmin Park, Dongkeun Yang.
Application Number | 20140314575 14/145180 |
Document ID | / |
Family ID | 49999809 |
Filed Date | 2014-10-23 |
United States Patent
Application |
20140314575 |
Kind Code |
A1 |
Cho; Namjoon ; et
al. |
October 23, 2014 |
TURBO FAN
Abstract
Provided is a turbo fan. The turbo fan includes a main plate
rotating by a fan motor providing power and a plurality of blades
having one ends connected to the main plate, the plurality of
blades being disposed along a circumferential direction on the main
plate. Each of the plurality of blades includes a first curved part
curved in one direction with respect to an extension part and a
second curved part curved in the other direction with respect to
the extension part. A plurality of projections protruding in one
direction from the one end of the blade and a plurality of grooves
protruding in the other direction are alternately disposed on the
first and second curved parts. Alternatively, the turbo fan
includes a main plate rotating by a fan motor providing power, a
rotation shaft providing a rotation center of the main plate, a
plurality of blades having a blade front end disposed adjacent to
the rotation shaft and a blade rear end disposed spaced from the
rotation shaft, the plurality of blades being disposed in a
circumferential direction on the main plate, and an extension part
defined as a virtual line straightly extending from an upper
portion of the blade rear end to a lower portion of the blade rear
end. Each of the blades includes a first curved part curved in one
direction with respect to the extension part, a second curved part
curved in the other direction with respect to the extension part, a
first flow part defined as a space between the extension part and
the first curved part, and a second flow part defined as a space
between the extension part and the second curved part.
Inventors: |
Cho; Namjoon; (Seoul,
KR) ; Yang; Dongkeun; (Seoul, KR) ; Park;
Youngmin; (Seoul, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LG Electronics Inc. |
Seoul |
|
KR |
|
|
Assignee: |
LG Electronics Inc.
Seoul
KR
|
Family ID: |
49999809 |
Appl. No.: |
14/145180 |
Filed: |
December 31, 2013 |
Current U.S.
Class: |
416/170R ;
416/189 |
Current CPC
Class: |
F04D 29/681 20130101;
F04D 29/666 20130101; F04D 29/30 20130101; F04D 29/282 20130101;
F04D 29/281 20130101; F05D 2240/304 20130101 |
Class at
Publication: |
416/170.R ;
416/189 |
International
Class: |
F04D 29/22 20060101
F04D029/22 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 19, 2013 |
KR |
10-2013-0043387 |
Claims
1. A turbo fan comprising: a main plate rotating by a fan motor
providing power; and a plurality of blades having one ends
connected to the main plate, the plurality of blades being disposed
along a circumferential direction on the main plate, wherein each
of the plurality of blades comprises: a first curved part curved in
one direction with respect to an extension part; and a second
curved part curved in the other direction with respect to the
extension part, wherein a plurality of projections protruding in
one direction from the one end of the blade and a plurality of
grooves protruding in the other direction are alternately disposed
on the first and second curved parts.
2. The turbo fan according to claim 1, wherein the first and second
curved parts are disposed on rear end of the blade, and the
extension part is defined as a virtual line straightly extending
from an upper portion of the rear end of the blade up to a lower
portion of the rear end of the blade.
3. The turbo fan according to claim 1, further comprising a shroud
connected to the other end of the blade to guide an inflow of air
into the blade, wherein the blade comprises: a first contact point
at which the main plate and the rear end of the blade meets each
other; and a second contact point at which the shroud and the rear
end of the blade meet each other, wherein the extension part is
defined as a virtual line straightly extending from the first
contact point up to the second contact point.
4. The turbo fan according to claim 1, wherein the blade further
comprises a crossing part defined as a point at which the extension
part and the rear end of the blade meet each other, wherein the
crossing part is defined as a boundary between the first curved
part and the second curved part.
5. The turbo fan according to claim 4, wherein the crossing part is
defined as a central point of the extension part, and the first
curved part has a length equal to that of the second curved
part.
6. The turbo fan according to claim 1, further comprising: an outer
circumferential surface that is a virtual line connecting the
plurality of projections to each other; and an inner
circumferential surface that is a virtual line connecting the
plurality of grooves to each other, wherein the outer
circumferential surface and the inner circumferential surface are
disposed parallel to each other.
7. The turbo fan according to claim 6, wherein the outer
circumferential surface and the inner circumferential surface have
the same curvature.
8. The turbo fan according to claim 6, wherein a vertical distance
between the outer circumferential surface and the inner
circumferential surface is constant.
9. The turbo fan according to claim 6, wherein the blade comprises:
a protrusion protruding from the inner circumferential surface
toward the inner circumferential surface to constitute one surface
of the blade; and a hollow disposed between the protrusions,
wherein the protrusion and the hollow are alternately disposed with
respect to each other.
10. The turbo fan according to claim 1, further comprising a
rotation shaft providing a rotation center of the main plate,
wherein the blade comprises: a blade front end disposed adjacent to
the rotation shaft; and a blade rear end disposed spaced from the
rotation shaft, wherein the plurality of projections and the
plurality of grooves are disposed on the blade rear end.
11. The turbo fan according to claim 10, wherein the plurality of
projections and the plurality of grooves protrude from the blade
front end toward the blade rear end.
12. The turbo fan according to claim 11, wherein the plurality of
curved parts protrude in a direction perpendicular to the
protruding direction of the plurality of projections.
13. The turbo fan according to claim 12, wherein each of the
plurality of projections and the plurality of grooves has a
predetermined curvature.
14. The turbo fan according to claim 12, wherein each of the
plurality of projections and the plurality of grooves has a
tip.
15. A turbo fan comprising: a main plate rotating by a fan motor
providing power; a rotation shaft providing a rotation center of
the main plate; a plurality of blades having a blade front end
disposed adjacent to the rotation shaft and a blade rear end
disposed spaced from the rotation shaft, the plurality of blades
being disposed in a circumferential direction on the main plate;
and an extension part defined as a virtual line straightly
extending from an upper portion of the blade rear end to a lower
portion of the blade rear end, wherein each of the blades
comprises: a first curved part curved in one direction with respect
to the extension part; a second curved part curved in the other
direction with respect to the extension part; a first flow part
defined as a space between the extension part and the first curved
part; and a second flow part defined as a space between the
extension part and the second curved part.
16. The turbo fan according to claim 15, wherein the blade further
comprises a crossing part defined as a point at which the extension
part and the blade rear end meet each other, wherein the crossing
part is defined as a boundary between the first flow part and the
second flow part.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority under 35 U.S.C. 119
and 35 U.S.C. 365 to Korean Patent Application No. 10-2013-0043387
(filed on Apr. 19, 2013), which is hereby incorporated by reference
in its entirety.
BACKGROUND
[0002] The present disclosure relates to a turbo fan.
[0003] Turbo fans may be used in ceiling type air conditioners that
are used in homes or companies. Hereinafter, such a ceiling type
air conditioner will be described as an example.
[0004] In general, ceiling type air conditioners are devices that
are buried in an indoor ceiling to discharge air heat-exchanged
after suctioning indoor air from the ceiling into an indoor space.
In such a ceiling type air conditioner, air may be suctioned
through a suction hole defined in a central portion of the ceiling
type air conditioner, and then, the suctioned air may be
heat-exchanged by a heat exchanger disposed within the ceiling type
air conditioner. The air-conditioned air may be discharged into the
indoor space through a discharge part disposed on a circumferential
portion of the ceiling type air conditioner to adjust a temperature
and moisture of the indoor space.
[0005] Particularly, the air suctioned through the suction hole may
be guided in movement by a turbo fan disposed within the ceiling
type air conditioner. That is, the turbo fan may introduce air in
an axial direction with respect to the turbo fan to discharge in a
radius direction of the turbo fan.
[0006] FIG. 1 is a perspective view of a turbo fan according to a
related art.
[0007] Referring to FIG. 1, a turbo fan 1 according to a related
art may include a main plate 10 rotating by power provided from a
motor, a plurality of blades 20 radially arranged on the main plate
10 and integrated with the main plate 10, and a shroud 30 coupled
to ends of the blades 20 to face one surface of the main plate
10.
[0008] Also, the turbo fan 1 may further include a hub 11
accommodating the motor therein, a boss part 12 having a shaft hole
in a central portion of the hub 11 so that the motor is
shaft-coupled to the shaft hole, and a vent part 13 defined in a
surface of the hub 11 to cool the motor. The vent part 13 may
introduce cold air into the motor therethrough to decrease a
temperature of the motor.
[0009] The air suctioned into the turbo fan 1 through a suction
hole 33 may be discharged to the outside of the turbo fan through a
discharge hole 34. The discharge hole 34 may be defined as a space
between the plurality of blades 20.
[0010] When the blades 20 rotate in a counterclockwise direction in
FIG. 1, air flowing along a back surface of each of the blades 20
may be discharged to the outside through the discharge hole 34.
However, the air flowing along the blades 20 may be spaced and
delaminated from surfaces of the blades 20. The delamination
phenomenon may cause noises when the turbo fan 1 operates.
[0011] Also, in recent years, with the large-scaled
air-conditioning system, an air volume required for the
air-conditioning system may be increasing more and more. Also, due
the increase of the air volume of the air-conditioner system, a
flow nose of air passing through the turbo fan 1 is increasing. As
a result, user's inconvenience may occur by the noise generated
from the turbo fan 1.
SUMMARY
[0012] Embodiments provide a turbo fan that is capable of reducing
an air flow noise generated when a turbo fan operates.
[0013] In one embodiment, a turbo fan includes: a main plate
rotating by a fan motor providing power; and a plurality of blades
having one ends connected to the main plate, the plurality of
blades being disposed along a circumferential direction on the main
plate, wherein each of the plurality of blades includes: a first
curved part curved in one direction with respect to an extension
part; and a second curved part curved in the other direction with
respect to the extension part, wherein a plurality of projections
protruding in one direction from the one end of the blade and a
plurality of grooves protruding in the other direction are
alternately disposed on the first and second curved parts.
[0014] In another embodiment, a turbo fan includes: a main plate
rotating by a fan motor providing power; a rotation shaft providing
a rotation center of the main plate; a plurality of blades having a
blade front end disposed adjacent to the rotation shaft and a blade
rear end disposed spaced from the rotation shaft, the plurality of
blades being disposed in a circumferential direction on the main
plate; and an extension part defined as a virtual line straightly
extending from an upper portion of the blade rear end to a lower
portion of the blade rear end, wherein each of the blades includes:
a first curved part curved in one direction with respect to the
extension part; a second curved part curved in the other direction
with respect to the extension part; a first flow part defined as a
space between the extension part and the first curved part; and a
second flow part defined as a space between the extension part and
the second curved part.
[0015] The details of one or more embodiments are set forth in the
accompanying drawings and the description below. Other features
will be apparent from the description and drawings, and from the
claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a perspective view of a turbo fan according to a
related art.
[0017] FIG. 2 is a perspective view illustrating an indoor unit of
a ceiling type air conditioner according to an embodiment.
[0018] FIG. 3 is a cross-sectional view illustrating the indoor
unit of the ceiling type air conditioner according to an
embodiment.
[0019] FIG. 4 is a perspective view of a blade according to an
embodiment.
[0020] FIG. 5 is a front view of the blade according to an
embodiment.
[0021] FIGS. 6a and 6b are a view illustrating various shapes of a
delamination delay part according to an embodiment.
[0022] FIG. 7 is a view illustrating a relationship between an air
volume and a noise when the blade according to an embodiment is
applied to the ceiling type air conditioner.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0023] Reference will now be made in detail to the embodiments of
the present disclosure, examples of which are illustrated in the
accompanying drawings.
[0024] In the following detailed description of the preferred
embodiments, reference is made to the accompanying drawings that
form a part hereof, and in which is shown by way of illustration
specific preferred embodiments in which the invention may be
practiced. These embodiments are described in sufficient detail to
enable those skilled in the art to practice the invention, and it
is understood that other embodiments may be utilized and that
logical structural, mechanical, electrical, and chemical changes
may be made without departing from the spirit or scope of the
invention. To avoid detail not necessary to enable those skilled in
the art to practice the invention, the description may omit certain
information known to those skilled in the art. The following
detailed description is, therefore, not to be taken in a limiting
sense.
[0025] A turbo fan may be used in home appliance of homes or
companies or factory machines. For example, the turbo fan may be
used in a ceiling type air conditioner. Hereinafter, the ceiling
type air conditioner to which the turbo fan is applied will be
described as an example.
[0026] FIG. 2 is a perspective view illustrating an indoor unit of
a ceiling type air conditioner according to an embodiment, and FIG.
3 is a cross-sectional view illustrating the indoor unit of the
ceiling type air conditioner according to an embodiment.
[0027] Referring to FIGS. 2 and 3, a ceiling type air conditioner
according to the current embodiment may include an outdoor unit
(not shown) installed in an outdoor space, an indoor unit 100
installed in an indoor space, and a refrigerant tube (not shown)
connecting the outdoor unit (not shown) to the indoor unit 100 to
allow a refrigerant to flow therethrough.
[0028] The indoor unit 100 may include a case 105 defining an outer
appearance thereof, a turbo fan 200 disposed within the case 105, a
fan motor 120 coupled to the turbo fan 200 to provide power, and a
heat exchanger 130 disposed outside the fan motor 120.
[0029] The case 105 may include a main body 101 defining side
surfaces thereof and a front panel 102 coupled to the main body 101
to define a front surface thereof.
[0030] Also, the main body 101 is installed in an indoor ceiling.
The main body 101 may have an opened lower portion to communicate
with a suction hole 150 defined in the front surface of the front
panel 102. Although the main body 101 is installed in the indoor
ceiling in consideration of space availability or a sense of
beauty, the installation space of the main body 101 is not limited
thereto. For example, the main body 101 may be installed in an
indoor sidewall.
[0031] The front panel 102 may be detachably coupled to the lower
portion of the main body 101. Also, the front panel 102 may be
exposed to the indoor space so that air is suctioned into or
discharged from the indoor unit 100. The front panel 102 may cover
the opened portion of the main body 101. For example, the front
panel 102 may have a square plate shape to cover the opening of the
main body 101. Also, the front panel 102 may include a suction hole
150 through which indoor air is suctioned and discharge holes 140
through which air is discharged into the indoor space.
[0032] The suction hole 150 may be defined in a central portion of
the front panel 102. Also, the discharge holes 140 may be
symmetrically defined in four sides of the suction hole 150. The
suction hole 150 may have a grill structure. Each of the discharge
holes 140 may have a rectangular structure with a predetermined
width and length. However, each of the suction hole 150 and the
discharge hole 140 are not limited to a shape thereof.
[0033] Also, a filter 190 for removing various foreign substances
contained in the air suctioned into the main body 101 through the
suction hole 150 may be provided inside the front panel 102.
[0034] The turbo fan 200 may include a hub 112 connected to a
rotation shaft of the fan motor 120, a main plate 115 rotating by
the fan motor 120, a plurality of blades 400 having one ends
connected to the main plate 115 and arranged at a predetermined
distance along a circumferential direction on the main plate 115,
and a shroud 300 facing the main plate 115 to connect the other
ends of the plurality of blades 400 to each other. The shroud 300
may guide an inflow of air into the suction hole 150 when the turbo
fan 200 rotates.
[0035] The turbo fan 200 may be disposed on a position
corresponding to the suction hole 150 to improve suction efficiency
of the air suctioned into the main body 101. Particularly, in FIG.
3, the turbo fan 200 may be disposed to correspond to a vertical
direction of the suction hole 150.
[0036] Also, the turbo fan 200 may blow the indoor air suctioned
through the suction hole 150 toward the heat exchanger 130.
[0037] The heat exchanger 130 may surround the outside of the turbo
fan 200. For example, the heat exchanger 130 may have a square
structure corresponding to a shape of each of the side surfaces of
the main body 101. The heat exchanger 130 may heat-exchange the air
suctioned into the main body 101 through the turbo fan 200.
[0038] Particularly, when the ceiling type air conditioner operates
in a cooling mode, air passing through the heat exchanger 130 may
decrease in temperature. On the other hand, when the ceiling type
air conditioner operates in a heating mode, air passing through the
heat exchanger 130 may increase in temperature.
[0039] A drain plate 131 accommodating condensed water generated
when the refrigerant passing through the heat exchanger 130 is
heat-exchanged with the indoor air may be disposed under the heat
exchanger 130. Also, a drain tube (not shown) for discharging the
condensed water collected in the drain plate 131 to the outside may
be connected to the drain plate 131.
[0040] A guide passage 180 for guiding a flow direction of air may
be defined in an outer portion of the inside of the main body 101.
Particularly, the guide passage 180 may guide the air
heat-exchanged by the heat exchanger 130 toward the discharge hole
140.
[0041] A vane 141 for controlling the flow direction of the air may
be disposed in the discharge hole 140. The vane 141 may be
rotatable at a predetermined angle. Also, the vane 141 may be
inclined outward from the front surface of the front panel 102.
This is done for providing wind having a uniform wind speed to all
indoor portions. However, the rotation direction of the vane 141 is
not limited thereto. Also, the vane 141 is not limited to an
arrangement, configuration, and operation method thereof.
[0042] When the turbo fan 200 operates, air introduced into the
turbo fan 200 may be discharged to the outside through a space
defined between the plurality of blades 400. That is, the air may
flow along surfaces of the plurality of blades 400. However, the
air flowing along the blades 400 may be spaced and delaminated from
the surfaces of the blades 400. The delamination phenomenon may
cause noises when the turbo fan 200 operates. Thus, in each of the
blades 400 according to the current embodiment, a protrusion 530
may be disposed on a rear end of the blade 400.
[0043] Hereinafter, a detailed structure of the blade 400 will be
described.
[0044] FIG. 4 is a perspective view of the blade according to an
embodiment.
[0045] Referring to FIG. 4, the blade 400 according to the current
embodiment may include a blade front end 410 disposed adjacent to
the hub 112 and a blade rear end 420 spaced from the hub 112. Thus,
the air introduced into the turbo fan 200 along the suction hole
150 may move from the blade front end 410 toward the blade rear end
420. Also, the air introduced into the turbo fan 200 may move along
the surface of the blade 400.
[0046] A plurality of curved part may be disposed on the blade rear
end 420. The plurality of curved parts may include a first curved
part 421 curved in one direction with respect to an extension part
500 and a second curved part 422 curved in the other direction with
respect to the extension part 500. The extension part 500 may be
defined as a virtual line extending from an upper end of the blade
rear end 410 up to a lower end of the blade rear end 420.
[0047] Particularly, when a point at which the main plate 115 and
the blade rear end 420 meet each other is referred to as a first
contact point 450, and a point at which the shroud 300 and the
blade rear end 420 meet each other is referred to as a second
contact point 460, the extension part 500 may be defined as a
virtual line defined to straightly extend from the first contact
point 450 up to the second contact point 460.
[0048] Each of the first curved part 421 and the second curved part
422 may have a curved surface with a predetermined curvature. For
example, the first curved part 421 may protrude in a left direction
with respect to the extension part 500. Also, the second curved
part 422 may protrude in a right direction with respect to the
extension part 500. However, each of the first and second curved
parts 421 and 422 is not limited to the protruding direction
thereof. For example, the first curved part 421 may protrude in the
right direction with respect to the extension part 500, and the
second curved part 422 may protrude in the left direction with
respect to the extension part 500.
[0049] The blade according to the current embodiment may further
include a crossing part 425 defined as a point at which the
extension part 500 and the blade rear end 420 meet each other. The
crossing part 425 may be defined as a boundary point between the
first curved part 421 and the second curved part 422. For example,
in FIG. 4, the first curved part 421 may be disposed at an upper
side with respect to the crossing part 425, and the second curved
part 422 may be disposed at a lower side with respect to the
crossing part 425.
[0050] The first curved part 421 and the second curved part 422 may
have the same length. That is, the crossing part 425 may be
disposed at a central point of the extension part 500. However,
each of the first and second curved parts 421 and 422 is not
limited to the length thereof.
[0051] A first flow part 502 may be disposed in a space between the
first curved part 421 and the extension part 500. Similarly, a
second flow part 504 may be disposed in a space between the second
curved part 422 and the extension part 500. Thus, the first and
second flow parts 502 and 504 may guide a flow direction of air
flowing from the blade front end 410 up to the blade rear end 420.
Thus, the air flow delamination phenomenon occurring at a side of
the blade rear end 420 may be delayed.
[0052] A plurality of projections 523 protruding in one direction
from the blade rear end 420 and a plurality of grooves 424
protruding in the other direction from the blade rear end 420 may
be disposed on the blade rear end 420.
[0053] The plurality of projections 423 and the plurality of
grooves 424 may be perpendicular to the protruding direction of the
curved part 421. That is, the plurality of projections 423 and the
plurality of grooves 424 may protrude from the blade front end 410
toward the blade rear end 420.
[0054] Hereinafter, a detailed structure of the blade rear end 420
will be described.
[0055] FIG. 5 is a front view of the blade according to an
embodiment.
[0056] Referring to FIG. 5, a delamination delay part 600 for
delaying the delamination of the air flowing along the surface of
the blade 400 from the surface of the blade 400 may be disposed on
the blade rear end 420. The delamination delay part 600 may be
defined as a space between a surface connecting the plurality of
projections 423 disposed on the blade 400 to each other and a
surface connecting the plurality of grooves 424 defined in the
blade 400 to each other.
[0057] When the surface connecting the plurality of projections 423
to each other is referred to as an outer circumferential surface
510, and the surface connecting the plurality of grooves 424 to
each other is referred to as an inner circumferential surface 520,
each of the outer and inner circumferential surfaces may have a
curved line with a predetermined curvature.
[0058] The outer and inner circumferential surfaces 510 and 520 may
be disposed parallel to each other. That is, the outer
circumferential surface 510 and the inner circumferential surface
520 may have the same curvature. Thus, all of the flow lamination
phenomena of air passing through an upper end of the blade 400 and
air passing through a lower end of the blade 400 may be
delayed.
[0059] The delamination delay part 600 disposed on the upper end of
the blade 400 may have a width L equal to that L' of the
delamination delay part 600 disposed on the lower end of the blade
400. That is, a vertical distance between the projection 423 and
the groove 424 may be constant.
[0060] Also, the delamination delay part 600 may further include a
protrusion 530 protruding from the inner circumferential surface
520 toward the outer circumferential surface 510 with respect to
the blade rear end 420 and a hollow 540 disposed between the
protrusions 530 and defined as a hollow space. The protrusion 530
may constitute a portion of the surface of the blade 400. That is
to say, the protrusion 530 may be defined as a portion of the
surface of the blade 400 defined between the outer circumferential
surface 510 and the inner circumferential surface 520. The
protrusion 530 and the hollow 540 may be alternately disposed with
respect to each other.
[0061] An eddy may be generated in the hollow 540. Thus, since the
air flowing from the blade front end 410 to the blade rear end 420
is guided toward the protrusion 530 by the eddy, the air flow
delamination phenomenon occurring at the blade rear end 420 may be
delayed.
[0062] FIGS. 6a and 6b a view illustrating various shapes of a
delamination delay part according to an embodiment.
[0063] Referring to FIG. 6a the blade rear end 420 may have a shape
with a predetermined curvature. Also, the delamination delay part
600 according to the current embodiment may include a plurality of
projections 423 and a plurality of grooves 424. The plurality of
projections 423 may include a first projection and a second
projection disposed adjacent to the first projection. If a distance
between the first projection and the second projection is referred
to as a distance A, and a length of the blade rear end 420 is
referred to as a length B, a value of distance A/length B may range
from about 0.05 to about 0.15. However, a ratio of the distance
between the first and second projections and a length of the blade
rear end 420 is not limited to the above-described value.
[0064] Also, if a height of the projection 423 with respect to the
inner circumferential surface 520 is referred to as a height C, and
a vertical distance from the blade front end 410 to the blade rear
end 420 is referred to as a vertical distance D, a value of height
C/vertical distance D may range from about 0.06 to about 0.20.
However, a ratio of the height of the projection 423 and the
vertical distance from the blade front end 410 to the blade rear
end 420 is not limited to the above-described value.
[0065] Also, the shape of the blade rear end 420 is not limited to
the curved line having the predetermined curvature.
[0066] Referring to FIG. 6b, the projection 623 may have one end
having a tip shape with a tip point. Similarly, the groove 624 may
also have the tip shape. Alternatively, the projection 423 the
projection 423 may have a curved line shape with a predetermined
curvature, and the groove 624 may have a tip shape.
[0067] FIG. 7 is a view illustrating a relationship between an air
volume and a noise when the blade according to an embodiment is
applied to the ceiling type air conditioner.
[0068] Referring to FIG. 7, when the ceiling type air conditioner
to which the blade according to the related art is applied
operates, a relationship between a wind volume and a noise may be
expressed as a dotted line N of FIG. 7. Also, when the ceiling type
air conditioner to which the blade according to the related art is
applied operates, a relationship between a wind volume and a noise
may be expressed as a solid line M of FIG. 7.
[0069] That is, if it is assumed that the wind volume of air
discharged from the ceiling type air conditioner is the same, a
noise generated when the ceiling type air conditioner to which the
blade according to the current embodiment is applied operates may
be less than that generated when the ceiling type air conditioner
to which the blade according to the related art is applied
operates.
[0070] That is, in the blade 400 according to the current
embodiment, a plurality of curved parts 421 and 422 may be disposed
on the blade rear end 420, and a delamination delay part 600 for
delaying the air flow delamination may be disposed on each of the
curved parts 421 and 422. Particularly, a plurality of projections
423 and a plurality of grooves 424 may be disposed on the plurality
of curved parts 421 and 422 to delay the air flow delamination
phenomenon occurring at the blade rear end 420.
[0071] Although embodiments have been described with reference to a
number of illustrative embodiments thereof, it should be understood
that numerous other modifications and embodiments can be devised by
those skilled in the art that will fall within the spirit and scope
of the principles of this disclosure. More particularly, various
variations and modifications are possible in the component parts
and/or arrangements of the subject combination arrangement within
the scope of the disclosure, the drawings and the appended claims.
In addition to variations and modifications in the component parts
and/or arrangements, alternative uses will also be apparent to
those skilled in the art.
* * * * *