U.S. patent application number 12/201857 was filed with the patent office on 2009-04-02 for heat exchanger and refrigeration cycle apparatus having the same.
Invention is credited to Dong Hwi Kim, Hong Seong Kim, Ju Hyok Kim, Han Choon Lee, Sang Yeul Lee, Yong Cheol Sa.
Application Number | 20090084129 12/201857 |
Document ID | / |
Family ID | 40149550 |
Filed Date | 2009-04-02 |
United States Patent
Application |
20090084129 |
Kind Code |
A1 |
Kim; Dong Hwi ; et
al. |
April 2, 2009 |
HEAT EXCHANGER AND REFRIGERATION CYCLE APPARATUS HAVING THE
SAME
Abstract
A heat exchanger including a plurality of first refrigerant
tubes, and a plurality of second refrigerant tubes separated from
the plurality of first refrigerant tubes in an air flow direction.
Further, a diameter of a respective refrigerant tube of the
plurality of first refrigerant tubes is smaller than a diameter of
a respective refrigerant tube of the plurality of second
refrigerant tubes.
Inventors: |
Kim; Dong Hwi; (Seoul,
KR) ; Sa; Yong Cheol; (Seoul, KR) ; Lee; Han
Choon; (Seoul, KR) ; Lee; Sang Yeul; (Seoul,
KR) ; Kim; Ju Hyok; (Seoul, KR) ; Kim; Hong
Seong; (Seoul, KR) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Family ID: |
40149550 |
Appl. No.: |
12/201857 |
Filed: |
August 29, 2008 |
Current U.S.
Class: |
62/502 ;
165/151 |
Current CPC
Class: |
F25B 39/00 20130101;
F28F 2210/08 20130101; F28F 1/325 20130101; F28D 2021/007 20130101;
F28F 2215/02 20130101; F28F 13/08 20130101; F28D 2021/0071
20130101; F28D 1/0477 20130101; F28D 1/05333 20130101; F25B 2500/01
20130101 |
Class at
Publication: |
62/502 ;
165/151 |
International
Class: |
F25B 1/00 20060101
F25B001/00; F28D 1/04 20060101 F28D001/04 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 31, 2007 |
KR |
10-2007-0088489 |
Claims
1. A heat exchanger, comprising: a plurality of first refrigerant
tubes; and a plurality of second refrigerant tubes separated from
the plurality of first refrigerant tubes in an air flow direction,
wherein a diameter of a respective refrigerant tube of the
plurality of first refrigerant tubes is smaller than a diameter of
a respective refrigerant tube of the plurality of second
refrigerant tubes.
2. The heat exchanger as claimed in claim 1, further comprising: at
least one fin configured to couple the plurality of first
refrigerant tubes to the plurality of second refrigerant tubes,
wherein the at least one fin includes first openings configured to
receive the plurality of first refrigerant tubes and second
openings configured to receive the plurality of second refrigerant
tubes, and wherein a diameter of a respective opening of the first
openings is smaller than a respective opening of the second
openings.
3. The heat exchanger as claimed in claim 2, wherein the at least
one fin includes a first fin unit configured to couple the
plurality of first refrigerant tubes and a second fin unit
configured to couple the plurality of second refrigerant tubes,
wherein the first fin unit includes a plurality of first slits and
the second fin unit includes a plurality of second slits, and
wherein forward slits of the plurality of first slits are longer
than backward slits of the plurality of second slits.
4. The heat exchanger as claimed in claim 3, wherein the plurality
of first slits are arranged asymmetrically with respect to the
plurality of second slits.
5. The heat exchanger as claimed in claim 1, wherein a ratio of the
diameter of the respective refrigerant tube of the plurality of
first refrigerant tubes to the diameter of the respective
refrigerant tube of the plurality of second refrigerant tubes is
0.3 to 0.95.
6. The heat exchanger as claimed in claim 5, wherein the diameter
of the respective refrigerant tube of the plurality of second
refrigerant tubes is 3 mm to 15 mm.
7. The heat exchanger as claimed in claim 6, wherein a distance
between centers of the plurality of first refrigerant tubes and a
distance between centers of the plurality of second refrigerant
tubes are 15 mm to 25 mm.
8. The heat exchanger as claimed in claim 2, wherein the at least
one fin has a width of 10 mm to 30 mm in the air flowing
direction.
9. The heat exchanger as claimed in claim 1, wherein each diameter
of the plurality of first refrigerant tubes is smaller than each
diameter of the plurality of second refrigerant tubes.
10. A refrigeration cycle apparatus comprising: a compressor
configured to compress a refrigerant; a condenser connected to the
compressor and configured to condense the refrigerant; an expander
connected to the condenser and configured to expand the
refrigerant; and an evaporator connected to the expander and the
compressor and configured to evaporate the refrigerant, wherein at
least one of the condenser and the evaporator includes a plurality
of first refrigerant tubes, and a plurality of second refrigerant
tubes separated from the plurality of first refrigerant tubes in an
air flow direction, wherein a diameter of a respective refrigerant
tube of the plurality of first refrigerant tubes is smaller than a
diameter of a respective refrigerant tube of the plurality of
second refrigerant tubes, and wherein the at least one of the
condenser and the evaporator further includes a connector
configured to connect together the respective refrigerant tube of
the plurality of first refrigerant tubes and the respective
refrigerant tube of the plurality of second refrigerant tubes so
that liquid refrigerant passes through the plurality of first
refrigerant tubes and that gas refrigerant passes through the
plurality of second refrigerant tubes.
11. The refrigeration cycle apparatus as claimed in claim 10,
wherein the connector is further configured to sequentially connect
the respective refrigerant tube of the plurality of second
refrigerant tubes and the respective refrigerant tube of the
plurality of first refrigerant tubes in a refrigerant flowing
direction so that refrigerant compressed by the compressor passes
through the plurality of second refrigerant tubes, passes through
the plurality of first refrigerant tubes, and flows to the
expander.
12. The refrigeration cycle apparatus as claimed in claim 10,
wherein the connector is further configured to sequentially connect
the respective refrigerant tube of the plurality of first
refrigerant tubes and the respective refrigerant tube of the
plurality of second refrigerant tubes in a refrigerant flowing
direction so that the refrigerant expanded by the expander passes
through the plurality of first refrigerant tubes, passes through
the plurality of second refrigerant tubes, and flows to the
compressor.
13. The refrigeration cycle apparatus as claimed in claim 10,
wherein a diameter of a first part of the connector connected to
the respective refrigerant tube of the plurality of first
refrigerant tubes is smaller than a diameter of a second part of
the connector connected to the respective refrigerant tube of the
plurality of second refrigerant tubes and an area of a channel
increases from the first part toward the second part.
14. The refrigeration cycle apparatus as claimed in claim 10,
wherein said at least one of the condenser and the evaporator
further includes at least one fin configured to couple the
plurality of first refrigerant tubes to the plurality of second
refrigerant tubes, wherein the at least one fin includes first
openings configured to receive the plurality of first refrigerant
tubes and second openings configured to receive the plurality of
second refrigerant tubes, and wherein a diameter of a respective
opening of the first openings is smaller than a respective opening
of the second openings.
15. The refrigeration cycle apparatus as claimed in claim 14,
wherein the at least one fin includes a first fin unit configured
to couple the plurality of first refrigerant tubes and a second fin
unit configured to couple the plurality of second refrigerant
tubes, wherein the first fin unit includes a plurality of first
slits and the second fin unit includes a plurality of second slits,
and wherein forward slits of the plurality of first slits are
longer than backward slits of the plurality of second slits.
16. The refrigeration cycle apparatus as claimed in claim 15,
wherein the plurality of first slits are arranged asymmetrically
with respect to the plurality of second slits.
17. The refrigeration cycle apparatus as claimed in claim 10,
wherein a ratio of the diameter of the respective refrigerant tube
of the plurality of first refrigerant tubes to the diameter of the
respective refrigerant tube of the plurality of second refrigerant
tubes is 0.3 to 0.95.
18. The refrigeration cycle apparatus as claimed in claim 17,
wherein the diameter of the respective refrigerant tube of the
plurality of second refrigerant tubes is 3 mm to 12 mm, and wherein
a distance between centers of the plurality of first refrigerant
tubes and a distance between centers of the plurality of second
refrigerant tubes are 15 mm to 25 mm.
19. The refrigeration cycle apparatus as claimed in claim 18,
wherein the at least one fin has a width of 10 mm to 30 mm in the
air flowing direction.
20. The refrigeration cycle apparatus as claimed in claim 10,
wherein each diameter of the plurality of first refrigerant tubes
is smaller than each diameter of the plurality of second
refrigerant tubes.
Description
[0001] This nonprovisional application claims priority under 35
U.S.C. .sctn. 119(a) on Patent Application No. 10-2007-0088489
filed in the Republic of Korea to Aug. 31, 2007, the entire
contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a heat exchanger for
exchanging heat between refrigerant and air and a refrigeration
cycle apparatus having the same, and more particularly, to a heat
exchanger in which a plurality of refrigerant tubes through which
refrigerant passes are provided back and forth in an air flowing
direction and a refrigeration cycle apparatus having the same.
[0004] 2. Description of the Background Art
[0005] A refrigeration cycle apparatus for cooling/heating the room
using a refrigeration cycle generally includes a compressor, a
condenser, an expander, and an evaporator. Further, a heat
exchanger including the condenser and the evaporator has a
refrigerant channel through which refrigerant passes.
[0006] Various types of heat exchangers exist. For example, in a
fin-tube type heat exchanger, a fin for increasing a heat transfer
area is coupled with a refrigerant tube through which refrigerant
passes. In more detail, FIG. 1 is a side view illustrating an
enlargement of a part of a background art heat exchanger.
[0007] As shown in the background art heat exchanger, refrigerant
flows in the inside of a plurality of columns of refrigerant tubes
102 and 104 and air A flows on the surface of a fin 106 that is an
enlarged surface connected to external sides of the refrigerant
tubes 102 and 104. To exchange heat between the refrigerant and the
air A, the heat exchanger has an optimal heat transfer area
suitable for the characteristics of the refrigerant and the
air.
[0008] In addition, the columns of refrigerant tubes 102 and 104
are arranged so that refrigerant tubes having the same diameter are
positioned back and forth in an air flowing direction and that the
latter columns of refrigerant tubes 104 are positioned in the rear
between former columns of refrigerant tubes 102.
[0009] Because a heat transfer coefficient of refrigerant varies in
accordance with diameters of the refrigerant tubes 102 and 104, the
temperature of the external sides of the refrigerant tubes varies.
Therefore, the amount of heat exchange between the refrigerant and
the air varies. In addition, for the air, the row pitch of the
refrigerant tubes 102 and 104 is set to have an enough heat
transfer area and the optimal heat transfer area of the air varies
in accordance with the diameter of the tubes.
[0010] However, the entire volume of the background art heat
exchanger having the above structure is determined by the diameters
of the refrigerant tubes 102 and 104 and the width L of the fin
106. Further, the heat exchanger is generally made to have a thin
shape. However, because the diameters of the refrigerant tubes 102
and 104 are equal to each other in the heat exchanger having the
above-described structure, the heat exchanger cannot be easily made
to have a thin shape.
[0011] Further, in the background art heat exchanger having the
above-described structure, a dead zone 108 to which the air is not
directly transferred exists in the rear parts of the refrigerant
tubes 102 and 104 so that the actual heat transfer area is
reduced.
SUMMARY OF THE INVENTION
[0012] Accordingly, one object of the present invention is to
address the above-noted and other drawbacks.
[0013] Another object of the present invention is to provide a heat
exchanger capable of being made thin and that minimizes a dead zone
to which air and refrigerant are not transferred to improve the
heat transfer performance of the heat exchange.
[0014] Yet another object of the present invention is to provide a
refrigeration cycle apparatus having a heat exchanger capable of
being made thin and that minimizes the pressure loss of
refrigerant.
[0015] To achieve these and other objects and in accordance with
the purpose of the present invention, as embodied and broadly
described herein, the present invention provides in one aspect a
heat exchanger including a plurality of first refrigerant tubes,
and a plurality of second refrigerant tubes separated from the
plurality of first refrigerant tubes in an air flow direction.
Further, a diameter of a respective refrigerant tube of the
plurality of first refrigerant tubes is smaller than a diameter of
a respective refrigerant tube of the plurality of second
refrigerant tubes.
[0016] In another aspect, the present invention provides a
refrigeration cycle apparatus including a compressor configured to
compress a refrigerant, a condenser connected to the compressor and
configured to condense the refrigerant, an expander connected to
the condenser and configured to expand the refrigerant, and an
evaporator connected to the expander and the compressor and
configured to evaporate the refrigerant. Further, at least one of
the condenser and the evaporator includes a plurality of first
refrigerant tubes, and a plurality of second refrigerant tubes
separated from the plurality of first refrigerant tubes in an air
flow direction, a diameter of a respective refrigerant tube of the
plurality of first refrigerant tubes is smaller than a diameter of
a respective refrigerant tube of the plurality of second
refrigerant tubes, and the at least one of the condenser and the
evaporator further includes a connector configured to connect
together the respective refrigerant tube of the plurality of first
refrigerant tubes and the respective refrigerant tube of the
plurality of second refrigerant tubes so that liquid refrigerant
passes through the plurality of first refrigerant tubes and that
gas refrigerant passes through the plurality of second refrigerant
tubes.
[0017] Further scope of applicability of the present invention will
become apparent from the detailed description given hereinafter.
However, it should be understood that the detailed description and
specific examples, while indicating preferred embodiments of the
invention, are given by illustration only, since various changes
and modifications within the spirit and scope of the invention will
become apparent to those skilled in the art from this detailed
description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The present invention will become more fully understood from
the detailed description given hereinbelow and the accompanying
drawings, which are given by illustration only, and thus are not
limitative of the present invention, and wherein:
[0019] FIG. 1 is a side view illustrating an enlargement of a part
of a background art heat exchanger;
[0020] FIG. 2 is an overview illustrating a heat exchanger
according to an embodiment of the present invention;
[0021] FIG. 3 is a side view illustrating an enlargement of a part
of the heat exchanger according to an embodiment of the present
invention;
[0022] FIG. 4 is a perspective view illustrating an enlargement of
a part of a fin of FIG. 3;
[0023] FIG. 5 is a partial sectional view illustrating a connector
connecting the former and latter columns of refrigerant tubes of
FIG. 3;
[0024] FIG. 6 is a graph illustrating a change in performance in
accordance with a diameter ratio of the columns of refrigerant
tubes of the heat exchanger according to an embodiment of the
present invention;
[0025] FIG. 7 is an overview illustrating a refrigeration cycle
apparatus having the heat exchanger according to an embodiment of
the present invention; and
[0026] FIG. 8 is a graph schematically comparing a heat transfer
performance of the heat exchanger according to an embodiment of the
present invention with a heat transfer performance of the
background art heat exchanger.
DETAILED DESCRIPTION OF THE INVENTION
[0027] Hereinafter, embodiments of the present invention will be
described in detail with reference to the accompanying
drawings.
[0028] FIG. 2 is an overview illustrating a heat exchanger
according to an embodiment of the present invention. As shown, the
heat exchanger includes a plurality of columns of refrigerant tubes
2 and 4 through which refrigerant passes and fins 10 coupling the
plurality of columns of refrigerant tubes 2 and 4. Further, the
plurality of fins 10 are coupled to the refrigerant tubes 2 and 4
by a predetermined distance.
[0029] In addition, the refrigerant tubes 2 and 4 are
longitudinally arranged to be orthogonal to the flowing direction
of air A and the fins 10 are arranged to run parallel to the
flowing direction of the air A. The refrigerant tubes 2 and 4 also
include former columns of refrigerant tubes 2 positioned in the
front in the air flowing direction and latter columns of
refrigerant tubes 4 positioned in the rear. The former columns of
refrigerant tubes 2 and the latter columns of refrigerant tubes 4
are integrally connected to each other so that refrigerant that
passes through the refrigerant tubes 2 and 4.
[0030] In addition, as shown in FIG. 3, the refrigerant tubes 2 and
4 are formed so that the diameter D1 of the former columns of
refrigerant tubes 2 is smaller than the diameter D2 of the latter
columns of refrigerant tubes 4. That is, in the heat exchanger
according to the present embodiment, the diameter of the former
columns of refrigerant tubes 2 is different from the diameter of
the latter columns of refrigerant tubes 4 such that the heat
exchanger can be made thinner. In particular, the refrigerant tubes
2 having a small diameter are used for the former columns to
increase the flow rate of the refrigerant affected by the sectional
area of the tubes and to increase the heat transfer coefficient of
the refrigerant tubes, in particular, the heat transfer coefficient
of the insides of the former columns of refrigerant tubes 2.
[0031] Further, when the refrigerant tubes having the small
diameter are used, the heat transfer coefficient increases in
accordance with an increase in the flow rate of the refrigerant,
However, because the heat transfer area of the insides of the
refrigerant tubes having the small diameter is reduced, when the
refrigerant tubes having the small diameter are used for the former
and latter columns of refrigerant tubes of the heat exchanger, the
total heat transfer amount is reduced so that the pressure loss of
the refrigeration apparatus is increased. In addition, when the
refrigerant tubes having the small diameter and the refrigerant
tubes having the large diameter are mixedly used for the former and
latter columns of refrigerant tubes 2 and 4, the increase in heat
transfer coefficient caused by the increase in the refrigerant flow
rate and the increase in the pressure loss are offset so that the
heat transfer amount is increased overall.
[0032] Further, the pressure loss is reduced than when all of the
former and latter columns of the refrigerant tubes 2 and 4 are
formed of the tubes having the large diameter. That is, although
the distance SP between the former and latter columns of
refrigerant tubes 2 and 4 is reduced, the pressure loss of the air
is not increased. Also, when the distance SP between the former and
latter columns of refrigerant tubes 2 and 4 is reduced, the fin
efficiency can be increased. In addition, due to the reduction in
the pressure loss of the air, the noise is minimized and the power
consumption of a fan for flowing the air to the heat exchanger is
reduced.
[0033] In addition, when the refrigerant tubes having the small
diameter are used as the former columns of refrigerant tubes 2, a
dead zone in the rear of the former columns of refrigerant tubes 2
is smaller than when the former columns of refrigerant tubes 2 have
the same diameter as the diameter of the latter columns of
refrigerant tubes 4.
[0034] Also, as shown in FIG. 3, the size of former columns of
colars 12 coupled to the former columns of refrigerant tubes 2 is
smaller than the size of latter columns of colars 14 coupled to the
latter columns of refrigerant tubes 4. Further, the diameter of the
latter columns of refrigerant tubes 4 is preferably set to be 3 mm
to 12 mm and the former columns of refrigerant tubes 2 and the
latter columns of refrigerant tubes 4 are formed so that the
distance SP between the tubes is 15 mm to 25 mm in a direction
perpendicular to the flowing direction of the air.
[0035] As illustrated in FIGS. 3 and 4, when the fin 10 is divided
back and forth into a forward fin unit 16 around the former columns
of refrigerant tubes 2 and a backward fin unit 18 around the latter
columns of refrigerant tubes 4 in the flowing direction of the air,
the sum of the width RP1 of the forward fin unit 16 and the width
RP2 of the backward fin unit 18 is about 10 mm to 30 mm.
[0036] Further, the fin 10 also includes slits 20 and 22 that
increase the heat transfer area through which the air passes. In
this embodiment, at least three columns of forward slits 20 are
formed in the forward fin unit 16 and at least three columns of
backward slits 22 are formed in the backward fin unit 18.
[0037] Also, the length SL1 of the forward slits 20 is preferably
0.3 mm to 1.5 mm and the length SL2 of the backward slits 22 is
preferably 0.3 mm to 1.5 mm. The forward slits 20 and the backward
slits 22 are also asymmetrical with each other so that heat
transfer performance is maximally improved. Further, the area of a
space between the former columns of refrigerant tubes 2 in the
forward fin unit 16 is larger when the diameter of the former
columns of refrigerant tubes 2 is different from the diameter of
the later columns of refrigerant tubes 4 than when the diameter of
the former columns of refrigerant tubes 2 is equal to the diameter
of the latter columns of refrigerant tubes 4. In addition, the
length SL1 of the forward slits 20 is longer than the length SL2 of
the backward slits 22.
[0038] Further, the width d1 of the forward slits 20 and the width
d2 of the backward slits 22 are preferably 0.5 mm to 2 mm. The
slits 20 and 22 are also formed in the same or opposite directions
as to the direction in which the colars 12 and 14 protrude and the
minimum distance between adjacent slits is preferably 0.5 mm.
[0039] In addition, in the slits 20 and 22, the length SL1, the
width d1, and the number of former columns of slits 20 are designed
to be optimal in accordance with the area of the latter columns of
slits 22 and the area of the parts excluding the slits 20 and 22 so
as to maximally secure the heat transfer performance. The distance
between the slits is also designed so that condensed water can be
easily discharged to actively transfer heat. In addition, the
length SL2, the width d2, and the number of the latter columns of
slits 22 are designed in accordance with the fin area different
from the fin area of the former columns of slits 20 so that it is
possible to maximally transfer the heat.
[0040] Further, as shown in FIG. 3, flat units 17 and 19 are formed
between the slits in the forward fin unit 16 and the backward fin
unit 18 and the widths d3 and d4 of the flat units 17 and 19 are
made large so that the condensed water can be easily discharged. In
addition, as illustrated in FIG. 5, a U-shaped connector 24
connected to a former column of refrigerant tube 2 and a latter
column of refrigerant tube 4 is provided to connect the refrigerant
tubes 2 and 4.
[0041] The connector 24 is also formed so that the diameter D3 of a
part 26 connected to the former column of refrigerant tube 2 is
smaller than the diameter D4 of a part 28 connected to the latter
column of refrigerant tube 4. In addition, the connector 24 is
formed so that the area of a channel increases from the part
connected to the former column of refrigerant tube 2 toward the
part 28 connected to the latter column of refrigerant tube 4.
[0042] Next, FIG. 6 is a graph illustrating a change in performance
in accordance with the diameter ratio of the former and latter
columns of refrigerant tubes of the heat exchanger according to an
embodiment of the present invention. In particular, FIG. 6
illustrates a heat transfer performance in accordance with the
ratio D1/D2 of the tubes 2 and 4.
[0043] Further, FIG. 6 illustrates an embodiment when the diameter
of the latter columns of refrigerant tubes 4 is 3 mm to 12 mm, the
distance SP between the former columns of refrigerant tubes 2 and
the distance SP between the latter columns of refrigerant tubes 4
are 11 mm to 25 mm and when the width of the air flowing direction
of the fin is 10 mm to 30 mm.
[0044] As shown, proper heat transfer performance can be maintained
when the ratio D1/D2 is 0.3 to 0.95. Further, the heat transfer
performance rapidly deteriorates when the ratio D1/D2 is Less than
0.3. That is, in the heat exchanger according to an embodiment of
the present embodiment, the ratio D1/D2 is 0.3 to 0.95. For
example, when the diameter D2 of the latter columns of refrigerant
tubes 4 is 7 mm, the diameter of the former columns of refrigerant
tubes 2 is set to be 2.1 mm to 6.65 mm.
[0045] Next, FIG. 7 is an overview illustrating a refrigeration
cycle apparatus having the heat exchanger according to an
embodiment of the present invention. As shown, the refrigeration
cycle apparatus includes a compressor 32 for circulating
refrigerant, a condenser 34, an expander 36 and an evaporator 38.
Also included is a condenser fan 35 for blowing the air to the
condenser 34 rotatably provided around the condenser 34. An
evaporator fan 39 for blowing the air to the evaporator 38 is also
rotatably provided around the evaporator 38.
[0046] Further, in the refrigeration cycle apparatus, the
evaporator 38 functions as an indoor heat exchanger for extracting
heat from the indoor air and evaporating the refrigerant, and the
condenser 34 functions as an outdoor hear exchanger for discharging
heat to the outdoor air and condensing the refrigerant.
[0047] Further, at least one of the condenser 34 and the evaporator
38 is formed of the heat exchanger illustrated in FIGS. 2 to 5.
That is, at least one of the condenser 34 and the evaporator 38 is
formed so that the diameter of the former columns of refrigerant
tubes 2 is smaller than the diameter of the latter columns of
refrigerant tubes 4 in the flowing direction of the air. In the
next description, both of the condenser 34 and the evaporator 38
are formed of the heat exchanger illustrated in FIGS. 2 to 5.
[0048] Further, when the condenser 34 and the evaporator 38 are
connected to each other so that liquid refrigerant passes through
the former columns of refrigerant tubes 2 and that gas refrigerant
passes through the latter columns of refrigerant tubes 4, the
condenser 34 and the evaporator 38 can be made thin and the
pressure loss of the refrigerant is minimized.
[0049] In addition, in the condenser 34, the latter columns of
refrigerant tubes 4, the former columns of refrigerant tubes 2, and
the expander are sequentially connected to each other in a
refrigerant flowing direction so that the refrigerant compressed by
the compressor 32 passes through the latter columns of refrigerant
tubes 4, passes through the former columns of refrigerant tubes 2,
and flows to the expander.
[0050] In the evaporator 38, the former columns of refrigerant
tubes 2 and the latter columns of refrigerant tubes 4 are
sequentially connected to each other in a refrigerant flowing
direction so that the refrigerant expanded by the expander 36
passes through the former columns of refrigerant tubes 2, passes
through the latter columns of refrigerant tubes 4, and flows to the
compressor 32.
[0051] Next, FIG. 8 is a graph schematically comparing a heat
transfer performance of the heat exchanger according to an
embodiment of the present invention with a heat transfer
performance when the diameters of the background art heat
exchanger.
[0052] In more detail, in FIG. 8, the heat transfer performance is
illustrated when the diameter of the former columns of refrigerant
tubes 2 is 5 mm, the diameter of the latter columns of refrigerant
tubes 4 is 7 mm, the sum of the width RP1 of the forward fin unit
16 and the width RFP2 of the backward fin unit 18 is about 20 mm,
the distance between the center of the former column of refrigerant
tube 2 and the center of the Latter column of refrigerant tube 4 is
9.5 mm, and the heat exchanger is used as the evaporator and the
condenser and is compared with the heat transfer performance when
the diameter of the former columns of refrigerant tubes 2 and the
diameter of the latter columns of refrigerant tubes 4 are 7 mm, the
sum of the width RP1 of the forward fin unit 16 and the width RFP
of the backward fin unit 18 is about 25.4 mm, the distance between
the center of the former column of refrigerant tube 2 and the
center of the latter column of refrigerant tube 4 is 10.5 mm, and
the heat exchanger is used as the evaporator and the condenser.
[0053] As shown, the heat transfer performance of the present
invention is greater than that of the background art. That is, in
the heat exchanger according to the present embodiment, as
illustrated in FIG. 5, although the width RP1 of the forward fin
unit 16 of the fin 10 and the width RP2 of the backward fin unit 18
of the fin 10 are smaller, when the heat exchanger is used as the
evaporator and the condenser, the heat transfer performance is
higher than when the diameter of the former columns of refrigerant
tubes 2 and the diameter of the latter columns of refrigerant tubes
4 are 7 mm.
[0054] In the heat exchanger according to embodiments of the
present invention having the above structure, among the plurality
of columns of referigerant tubes, the diameter of the former
columns of refrigerant tubes is smaller than the diameter of the
latter columns of refrigerant tubes in the air flowing direction.
Therefore, the heat exchanger can be made thin in the air flowing
direction and a dead zone in which air and heat are not exchanged
among the refrigerant tubes of the heat exchanger can be minimized
to improve the heat transfer performance.
[0055] In the refrigeration cycle apparatus having the heat
exchanger according to the present invention, liquid refrigerant
flows through the former columns of refrigerant tubes having the
small diameter and gas refrigerant flows through the latter columns
of refrigerant tubes having the large diameter so that the
condenser and the evaporator can be made thin and the pressure loss
of the refrigerant can be minimized.
[0056] Thus, according to an embodiment of the present invention,
the heat exchanger includes the plurality of columns of refrigerant
tubes and the diameter of the former columns of refrigerant tubes
is smaller than the diameter of the latter columns of refrigerant
tubes in the air flowing direction. Therefore, the heat exchanger
can be made thin and can be used for a refrigeration cycle
apparatus capable of minimizing the pressure loss of the
refrigerant. The dead zone and pressure loss can also be
minimized.
[0057] As the present invention may be embodied in several forms
without departing from the spirit or essential characteristics
thereof, it should also be understood that the above-described
embodiments are not limited by any of the details of the foregoing
description, unless otherwise specified, but rather should be
construed broadly within its spirit and scope as defined in the
appended claims, and therefore all changes and modifications that
fall within the metes and bounds of the claims, or equivalence of
such metes and bounds are therefore intended to be embraced by the
appended claims.
* * * * *