U.S. patent application number 12/582111 was filed with the patent office on 2010-05-27 for indoor unit for air conditioning apparatus.
Invention is credited to Deok Huh, Jeong Taek Park, Ki Won Seo.
Application Number | 20100126206 12/582111 |
Document ID | / |
Family ID | 41527851 |
Filed Date | 2010-05-27 |
United States Patent
Application |
20100126206 |
Kind Code |
A1 |
Park; Jeong Taek ; et
al. |
May 27, 2010 |
INDOOR UNIT FOR AIR CONDITIONING APPARATUS
Abstract
An indoor unit for an air conditioning apparatus is provided.
The indoor unit includes a cross flow fan having a structure that
can reduce noise and flow resistance of air passing through a heat
exchanger in the indoor unit.
Inventors: |
Park; Jeong Taek; (Seoul,
KR) ; Huh; Deok; (Seoul, KR) ; Seo; Ki
Won; (Seoul, KR) |
Correspondence
Address: |
KED & ASSOCIATES, LLP
P.O. Box 221200
Chantilly
VA
20153-1200
US
|
Family ID: |
41527851 |
Appl. No.: |
12/582111 |
Filed: |
October 20, 2009 |
Current U.S.
Class: |
62/419 ;
165/121 |
Current CPC
Class: |
F24F 7/007 20130101;
F24F 1/0025 20130101; F24F 1/0007 20130101; F04D 29/30 20130101;
F24F 1/0057 20190201; F04D 29/283 20130101; F24F 13/24
20130101 |
Class at
Publication: |
62/419 ;
165/121 |
International
Class: |
F25D 17/06 20060101
F25D017/06; F28D 21/00 20060101 F28D021/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 26, 2008 |
KR |
10-2008-0117860 |
Claims
1. An indoor unit for an air conditioning apparatus, comprising: a
chassis, including: a stabilizer; and a fan insertion groove formed
at a first end of the stabilizer and a fan supporter provided at a
second end of the stabilizer; a cross flow fan supported in the
chassis by the fan insertion groove and the fan supporter, and
extending across a portion of the stabilizer, wherein the fan draws
indoor air into the indoor unit and the stabilizer guides the
indoor air through the indoor unit; and a heat exchanger provided
an inlet side of the cross flow fan so as to perform a heat
exchange with the indoor air, wherein a ratio of a thickness T of a
blade of the fan to a chord length L of the blade of the fan is
greater than or equal to 0.088 and less than or equal to 0.132.
2. The indoor unit of claim 1, wherein a ratio of an inner diameter
D1 to an outer diameter D2 of the fan is greater than or equal to
0.77 and less than or equal to 0.80.
3. The indoor unit of claim 1, wherein an outer circumferential
angle .beta.2 of the cross flow fan is greater than or equal to 30
degrees and less than or equal to 32 degrees.
4. The indoor unit of claim 1, wherein a ratio of an insertion
depth t of the fan to the chord length L of the blade is greater
than or equal to 0.0044 and less than or equal to 0.0143.
5. The indoor unit of claim 1, further comprising: a front frame
coupled to the chassis so as to form an interior space of the
indoor unit therebetween, wherein the fan and the heat exchanger
are positioned in the interior space; an inlet grill and an inlet
port formed in the front frame, each at positions corresponding to
respective portions of the heat exchanger so as to guide indoor air
therethrough and into the heat exchanger; a front panel movably
coupled to the front frame so as to selectively open and close the
inlet port; and a discharge grill coupled to the front frame and
positioned so as to define an outlet port together with the
chassis.
6. The indoor unit of claim 5, wherein the heat exchanger is
positioned in the interior space between the inlet grill and the
fan, and between the inlet port and the fan, such that rotation of
the fan draws indoor air through the inlet grill and the inlet port
and through the heat exchanger for heat exchange, and then draws
heat exchanged air through the fan for discharge from the indoor
unit through the outlet port.
7. The indoor unit of claim 5, further comprising: a louver
rotatably positioned between an outlet of the fan and the outlet
port, wherein the louver controls a lateral flow direction of heat
exchanged air through the outlet port; and a vane rotatably
positioned at the outlet port, wherein the vane selectively opens
and closes the outlet port and controls a vertical flow direction
of heat exchanged air through the outlet port.
8. The indoor unit of claim 1, wherein the fan includes a plurality
of blades each having a predetermined curvature from a root end to
a tip end thereof, and a mean camber line that bisects the
thickness T of the blade and follows the predetermined curvature of
the blade.
9. The indoor unit of claim 8, wherein an inner circumferential
angle .beta.1 is formed between a first line that connects a root
end of the mean camber line and a center of the fan and a second
line that extends tangentially through the root end of the blade,
and an outer circumferential angle .beta.2 is formed between a
third line formed as an extension of the mean camber line from a
tip end of the blade and a fourth line that extends tangentially
through the tip end of the blade.
10. The indoor unit of claim 8, wherein the predetermined curvature
of the blade includes a first predetermined curvature that defines
a first surface of the blade, and a second predetermined curvature
that defines a second surface of the blade opposite the first
surface, wherein the first predetermined curvature is different
from the second predetermined curvature such that the thickness T
of the blade varies along the chord length.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This claims the priority to Korean Patent Application No.
10-2008-0117860 (filed in Korea on Nov. 26, 2008), the entirety of
which is incorporated herein by reference.
BACKGROUND
[0002] 1. Field
[0003] An air conditioning system is provided, and in particular an
indoor unit for an air conditioning system is provided.
[0004] 2. Background
[0005] In general, an air conditioning apparatus cools/heats a room
using a compressor, a condenser, an expander, and an evaporator.
The air conditioning apparatus may be a separated-type air
conditioning apparatus in which an indoor unit is separated from an
outdoor unit, or an integrated-type air conditioner in which an
indoor unit is integrated with an outdoor unit. Improvements in
efficiency, effectiveness and noise level during operation are
desirable in either type of air conditioning apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The embodiments will be described in detail with reference
to the following drawings in which like reference numerals refer to
like elements, wherein:
[0007] FIG. 1 is a side cross-sectional view of a structure of an
indoor unit for an air conditioning apparatus according to an
embodiment as broadly described herein;
[0008] FIG. 2 is a front perspective view of a chassis of the
indoor unit shown in FIG. 1;
[0009] FIG. 3 is a partial perspective view of a fan of the indoor
unit shown in FIG. 1;
[0010] FIG. 4 is a side view of the fan shown in FIG. 3;
[0011] FIG. 5 is a perspective view of a blade corresponding to a
portion A of FIG. 4;
[0012] FIG. 6 is a graph of a relationship between an outer
circumferential angle and noise in a fan of an indoor unit
according to an embodiment as broadly described herein;
[0013] FIG. 7 is a graph of a relationship between a ratio of inner
diameter to outer diameter and noise in a fan of an indoor unit
according to an embodiment as broadly described herein;
[0014] FIG. 8 is a graph of a relationship between a ratio of
thickness to length of a fan and noise in a fan of an indoor unit
according to an embodiment as broadly described herein;
[0015] FIG. 9 is a graph of a relationship between a ratio of an
insertion depth to length of a fan and noise in a fan of an indoor
unit according to an embodiment as broadly described herein;
and
[0016] FIG. 10 is a graph of noise performance improvement of an
indoor unit including a fan and an indoor unit as embodied and
broadly described herein.
DETAILED DESCRIPTION
[0017] In a separated air conditioning apparatus, a fan and a heat
exchanger that performs a heat exchange operation with indoor air
drawn in by the fan may be received in the indoor unit. Air may
flow from, for example, a front upper surface of the indoor unit
downward to be discharged at a lower portion of the front surface
of the indoor unit. A high efficiency cross flow fan may be
installed in an indoor unit that is installed on a wall surface to
reduce power consumption.
[0018] A heat exchanger that has an increased heat exchange area
may also be used to improve efficiency. Such a heat exchanger may
include coolant pipes arranged in 3 rows forward and backward.
However, if this type of 3 row heat exchanger is used in an indoor
unit in combination with a cross flow fan, system resistance may be
increased. As system resistance is increased, the noise level at a
given air flow rate may also be increased. For example, a surging
noise may be generated. A structure in which the fan may be
operated at a desired level without generating abnormal noise would
be beneficial, especially when air resistance is increased due to
dust accumulated on a heat exchanger or a filter after extended
use, and a 3 row heat exchanger and cross flow fan are used.
[0019] FIG. 1 is a side cross-sectional view of an indoor unit 10
for an air conditioning apparatus, including a chassis 11 that may
be closely adhered to a support surface, such as, for example, a
wall, a front frame 12 that is coupled to a front side of the
chassis 11, a front panel 13 that is rotatably or slidably provided
on a front surface of the front frame 12, a fan 17 that is received
in a space formed by the chassis 11 and the front frame 12 to draw
indoor air into the indoor unit 10, and a heat exchanger 16 that
surrounds the fan 17 to perform a heat exchange operation with the
indoor air.
[0020] A stabilizer 112 may be provided on a front surface of the
chassis 11 to allow air flow to be generated as the fan 17 rotates.
A heat exchanger seating part 111 that supports a first end of the
heat exchanger 16 may be formed on an upper side of the stabilizer
112. An inlet grill 121 may be formed on an upper surface of the
front frame 12 to guide the flow of indoor air into the indoor unit
10, and a front surface inlet port 122 may be formed on a front
surface of the front frame 12. A filter 15 may be mounted on a
front surface of the heat exchanger 16 to filter indoor air drawn
in through the inlet grill 121 and the front surface inlet port
122.
[0021] As the indoor unit 10 operates, an upper end or a lower end
of the front panel 13 may be rotated away from the front frame 12
or may be moved vertically relative to the front frame 12 to allow
the front surface inlet port 122 to be opened or exposed. A
discharge grill 14 may be provided on a lower end of the indoor
unit 10 so that a second end of the heat exchanger 16 may be seated
on an upper side of the discharge grill 14. An air outlet port 141
may be formed on a lower side of the discharge grill 14. A lower
end of the stabilizer 112 may extend to the air outlet port 141. A
discharge louver 143 that controls a leftward and rightward flow of
discharged air and a discharge vane 142 that not only selectively
opens/closes the air outlet port 141 but also controls an upward
and downward flow of the discharged air may each be provided on the
air outlet port 141. The discharge vane 142 and the discharge
louver 143 may be rotatably coupled to each other on a lower side
of the discharge grill 14. In certain embodiments, the heat
exchanger 16 may have a shape in which coolant pipes are arranged
in 3 rows from front to back or are divided into plural sections so
as to surround a front and an upper portion of the fan 17, and the
fan 17 may be a cross flow fan.
[0022] FIG. 2 is a front perspective view of the chassis shown in
FIG. 1. In the embodiment shown in FIG. 2, the heat exchanger
seating part 111 and the stabilizer 112 are formed on the front
surface of the chassis 11, and a fan supporter 114 is provided at a
first end of the chassis 11, along a corresponding end of the
stabilizer 112. A motor seating part 113 is provided on a side of
the fan supporter 114 to support a motor that drives the fan 17. A
fan insertion groove 115 may be formed at a second end of the
chassis 11 opposite the first end. The fan insertion groove 115 may
have a predetermined depth t, or thickness, to support the
corresponding end of the fan 17.
[0023] Fan noise may be generated differently depending on the
extent to which the fan insertion groove 115 extends into the
chassis 11, its thickness or depth t, and its shape. Therefore, the
depth t of the fan insertion groove 115 may be one design factor to
consider for reducing noise of the indoor unit 10. Hereinafter, the
relationship between the depth t of the fan insertion grove 115 and
noise, and determination of an appropriate depth t of the fan
insertion groove 115 will be explained.
[0024] Referring to FIGS. 3 and 4, the fan 17 included with an
indoor unit 10 as embodied and broadly described herein may be a
cross flow fan, and the cross flow fan may include a plurality of
blades 171 that are radially arranged in a circumferential
direction. Each blade 171 may be slanted at a predetermined angle
.theta., such that a line that extends along a width s (see FIG. 5)
direction of each blade is not parallel to a rotation shaft of the
fan 17, but instead is slanted by the predetermined angle .theta..
The fan 17 defines a mean camber line by means of an inner diameter
D1 from a center to an inner end, or root end, of the blade 171, an
outer diameter D2 from a center to an outer end, or tip end, of the
blade 171, an inner circumferential angle .beta.1 and an outer
circumferential angle .beta.2. The mean camber line of the blade
171 (hereinafter, referred to as a camber line) is a line that
bisects a thickness T of the blade 171, essentially following the
contour of the blade.
[0025] The inner circumferential angle .beta.1 is an angle defined
by a line connecting the inner end, or root end, of the camber line
to the center of the fan 17 and a tangential line that passes
through the inner end, or root end, of the camber line at the inner
diameter D1. Hereinafter, the inner circumferential angle .beta.1
will be set to approximately 90 degrees. The outer circumferential
angle .beta.2 is an angle is defined by a straight line that
extends outward from the outer end, or tip end, of the camber line
and a tangential line that passes through the outer end, or tip
end, of the camber line at the outer diameter D2.
[0026] Referring to FIG. 5, the blade 171 may have a predetermined
chord length L and a predetermined width s and may be somewhat
rounded in the length L direction. More specifically, an inner
curvature p1 of the blade 171 (at a surface of the blade 171 that
is oriented toward the center of the fan 17) may be different from
an outer curvature p2 thereof (at a surface of the blade 117 that
is oriented away from the center of the fan 17). Therefore, a
thickness of the edge portion of the blade 171 may be different
from that of the central portion. In other words, the blade 171 has
a shape that is thick and then becomes thin from one end to the
other end. And, the length L of the blade 171 is defined based on a
straight line distance from the inner, root, end of the blade 171
to the outer, tip, end thereof.
[0027] In an indoor unit 10 in which the fan 17 constituted as
described above is installed, the relationship between a ratio of
inner diameter D1 to outer diameter D2 of the fan 17 and noise, the
relationship between an outer circumferential angle .beta.2 and
noise, the relationship between a ratio of thickness T to length L
of a fan and noise, the relationship between a ratio of an
insertion depth t of a side end of a fan to a length L of the fan
and noise, may all be taken into consideration in reducing fan
noise.
[0028] FIG. 6 is a graph of the relationship between an outer
circumferential angle .beta.2 and noise in a fan in which an inner
circumferential angle .beta.1 is set to approximately 90 degrees.
As shown in FIG. 6, noise is on a downward trend and continues to
be reduced until the outer circumferential angle .beta.2 of the
blade 171 reaches approximately 30 degrees and then begins to
increase as it exceeds 30 degrees. Thus, noise may be minimized
when the outer circumferential angle .beta.2 is approximately 30
degrees. In certain embodiments, the outer circumferential angle
.beta.2 of the blade 171 is preferably 28
degrees.ltoreq..beta.2.ltoreq.32 degrees, and more preferably, 30
degrees.ltoreq..beta.2.apprxeq.32 degrees.
[0029] FIG. 7 is a graph of the relationship between a ratio of
inner diameter to outer diameter D1/D2 and noise in a fan of an
indoor unit as embodied and broadly described herein. As shown in
FIG. 7, noise is on a downward trend and continues to be reduced
until the ratio of inner diameter to outer diameter D1/D2 is
approximately 0.79 and then increases as the ratio of inner
diameter D1/D2 to outer diameter exceeds 0.79. In certain
embodiments, the ratio of inner diameter to outer diameter of the
blade 171 is preferably 0.77.ltoreq.D1/D2.ltoreq.0.81, and more
preferably, 0.77.ltoreq.D1/D2.ltoreq.0.8.
[0030] FIG. 8 is a graph of the relationship between a ratio of
thickness to length T/L of a fan blade 117 and noise in a fan of an
indoor unit according to an embodiment as broadly described herein.
As shown in FIG. 8, noise is on a downward trend and continues to
be reduced until the ratio of thickness to length T/L reaches
approximately 0.1, and then increases as the ratio of thickness to
length T/L exceeds 0.1. In other words, the noise level is
minimized at a point where the ratio of thickness to length T/L is
approximately 0.1. In certain embodiments, the ratio of thickness
to length of a fan is preferably 0.088.ltoreq.T/L.ltoreq.0.132.
[0031] FIG. 9 is a graph of a relationship between a ratio of an
insertion depth t to length L and noise in a fan of an indoor unit
according to an embodiment as broadly described herein. As shown in
FIG. 9, noise is on a downward trend and continues to be reduced
until the ratio of an insertion depth to length t/L reaches
approximately 0.007, and then increases as the ratio of an
insertion depth to length t/L exceeds 0.007. In other words, the
noise level is minimized at a point where the ratio of an insertion
depth to length is approximately 0.007. In certain embodiments, the
ratio of thickness to length t/L is preferably
0.0044.ltoreq.t/L.ltoreq.0.0143.
[0032] Thus, a blowing function may be improved or maximized in a
fan of an indoor unit as embodied and broadly described herein when
designed based on the noise level parameters shown in FIGS. 6 to 9.
In particular, the blowing function may be improved and the noise
level may be reduced when a fan 17 and its blade 171 have a
structure that takes these parameters into consideration.
[0033] FIG. 10 is a graph of noise performance improvement of an
indoor unit including such a fan. As shown in FIG. 10, noise
generated by a fan that does not include the improved structure as
described above is represented by the lighter, grey portion of the
graph, while noise generated by a fan including the improved
structure as described above is represented by the black portion of
the graph. A mean, or average, noise difference between these two
exemplary fans, i.e., the mean or average of the noise level
difference between the "before" and "after" lines at measured
corresponding points is approximately 2.2. Thus, noise may be
reduced by about 2.2 dB when the structure of the fan is improved
as described above. This allows blowing performance of the fan to
be increased and system resistance and fan noise to be reduced, and
may be applied regardless of the size of the indoor unit and/or the
size of the fan.
[0034] An indoor unit for an air conditioning apparatus as embodied
and broadly described herein may include a chassis including a
stabilizer that generates a flow of air, and a fan insertion
groove; a cross flow fan that is mounted on a front surface of the
chassis corresponding to an upper end of the stabilizer, to inhale
indoor air; a heat exchanger that is provided on a front side of
the fan to perform a heat exchange with the indoor air, wherein
0.088.ltoreq.T/L.ltoreq.0.132 (T: thickness of fan, L: length of
fan).
[0035] In an indoor unit for an air conditioning apparatus as
embodied and broadly described herein, system resistance may be
reduced even when a 3 row heat exchanger is applied in order to
improve heat exchange efficiency of the indoor unit. Also, although
resistance due to dust accumulated on a heat exchanger or a filter
is increased due to extended use, the fan may be normally operated
without generating abnormal noise. Also, although a 3 row heat
exchanger is used, the noise level may be reduced.
[0036] Any reference in this specification to "one embodiment," "an
embodiment," "example embodiment," etc., means that a particular
feature, structure, or characteristic described in connection with
the embodiment is included in at least one embodiment of the
invention. The appearances of such phrases in various places in the
specification are not necessarily all referring to the same
embodiment. Further, when a particular feature, structure, or
characteristic is described in connection with any embodiment, it
is submitted that it is within the purview of one skilled in the
art to effect such feature, structure, or characteristic in
connection with other ones of the embodiments.
[0037] 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, numerous
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.
* * * * *