U.S. patent application number 11/262895 was filed with the patent office on 2006-05-04 for air conditioner.
This patent application is currently assigned to LG Electronics Inc.. Invention is credited to Se Dong Chang, Baik Young Chung, Ju-Won Kim, Sai-Kee Oh, Bong-Soo Park, Chi-Woo Song.
Application Number | 20060090487 11/262895 |
Document ID | / |
Family ID | 35840354 |
Filed Date | 2006-05-04 |
United States Patent
Application |
20060090487 |
Kind Code |
A1 |
Park; Bong-Soo ; et
al. |
May 4, 2006 |
Air conditioner
Abstract
Disclosed is an air conditioner. The air conditioner includes:
at least one indoor unit; an outdoor unit communicating with the
indoor unit and having at least one compressor and one outdoor heat
exchanger; a fluid path opening/closing valve for opening or
closing a fluid path through which a refrigerant can flow to the
outdoor heat exchanger; and a control unit for controlling the
compressor and the fluid path opening/closing valve to perform
appropriate compression and condensation of the refrigerant
according to the load amount of the indoor unit. Accordingly, as
the air conditioner comprises the fluid path opening/closing valve
and the branch fluid path opening/closing valve which are capable
of opening or closing fluid paths and a control unit for
controlling the valves, a high pressure of a cycle is appropriately
maintained even during small-load operation and therefore
reliability in operation can be increased.
Inventors: |
Park; Bong-Soo; (Seoul,
KR) ; Oh; Sai-Kee; (Gyeonggi-Do, KR) ; Chung;
Baik Young; (Incheon, KR) ; Chang; Se Dong;
(Gyeonggi-Do, KR) ; Song; Chi-Woo; (Incheon,
KR) ; Kim; Ju-Won; (Gyeongsangnam-Do, KR) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Assignee: |
LG Electronics Inc.
|
Family ID: |
35840354 |
Appl. No.: |
11/262895 |
Filed: |
November 1, 2005 |
Current U.S.
Class: |
62/160 ;
62/324.1 |
Current CPC
Class: |
F25B 13/00 20130101;
F25B 49/027 20130101; F25B 2400/075 20130101; F25B 2313/0252
20130101; F25B 2313/02531 20130101; F25B 2313/02533 20130101; F25B
2313/0231 20130101 |
Class at
Publication: |
062/160 ;
062/324.1 |
International
Class: |
F25B 13/00 20060101
F25B013/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 3, 2004 |
KR |
88948/2004 |
Claims
1. An air conditioner comprising: at least one indoor unit; an
outdoor unit communicating with the indoor unit and having at least
one compressor and one outdoor heat exchanger; a fluid path
opening/closing valve for opening or closing a fluid path through
which a refrigerant can flow to the outdoor heat exchanger; and a
control unit for controlling the compressor and the fluid path
opening/closing valve to perform appropriate compression and
condensation of the refrigerant according to the load amount of the
indoor unit.
2. The air conditioner of claim 1, wherein the fluid path
opening/closing valve is disposed on the upstream side of the
outdoor heat exchanger along the direction of the refrigerant
flow.
3. The air conditioner of claim 2, wherein the fluid path
opening/closing valve is an electric valve.
4. The air conditioner of claim 1, wherein the control unit,
according to the load amount obtained by calculating the load when
some indoor units are operated, controls the compressors such that
some compressors are operated or the compressors are operated at
low frequencies, and opens or closes the fluid path opening/closing
valve.
5. The air conditioner of claim 1, wherein the outdoor heat
exchanger comprises: a plurality of heat exchange units in which
the refrigerant branches off and flows, and performing heat
exchange; a header having branch fluid paths through which the
refrigerant can branch off and be supplied to the heat exchange
units; and a distributor connected with the heat exchange
units.
6. The air conditioner of claim 5, further comprising: a branch
fluid path opening/closing valve for opening or closing the branch
fluid path.
7. The air conditioner of claim 6, wherein the branch fluid path
comprises: an upstream branch fluid path for connecting the header
with the heat exchange units; and a downstream fluid path for
connecting the heat exchange units and the distributor, wherein the
branch fluid path opening/closing valve is installed at either the
upstream branch fluid path or the downstream branch fluid path.
8. The air conditioner of claim 6, wherein the branch fluid path
comprises: an upstream branch fluid path through which the header
is connected with the heat exchange units; and a downstream fluid
path through which the heat exchange units are connected with the
distributor, wherein the branch fluid path opening/closing valves
are installed at both the upstream branch fluid path and the
downstream branch fluid path.
9. The air conditioner of claim 6, wherein the control unit,
according to the load amount obtained by calculating the load when
some indoor units are operated, controls the compressors such that
some compressors are operated or the compressors are operated at
low frequencies, and opens or closes the fluid path opening/closing
valve and the branch fluid path opening/closing valve.
10. The air conditioner of claim 6, wherein the outdoor unit
comprises a main outdoor unit and a sub-outdoor unit connected and
installed in parallel.
11. The air conditioner of claim 10, further comprising: a pressure
equalizing pipe for allowing the upstream side of the outdoor heat
exchanger of the main outdoor unit and the upstream side of the
outdoor heat exchanger of the sub-outdoor unit to communicate with
each other.
12. The air conditioner of claim 10, wherein the fluid path
opening/closing valves are installed on the upstream side of the
outdoor heat exchanger of the main outdoor unit and on the upstream
side of the outdoor heat exchanger of the sub-outdoor unit.
13. The air conditioner of claim 10, wherein the branch fluid path
opening/closing valve is installed at the downstream branch fluid
path of the outdoor heat exchanger of the main outdoor unit.
14. The air conditioner of claim 10, wherein the control unit,
according to the load amount obtained by calculating the load when
some indoor units are operated, controls the compressors such that
some compressors of the main outdoor unit and the sub-outdoor unit
are operated or the compressors are operated at low frequencies,
and opens or closes the fluid path opening/closing valve and the
branch fluid path opening/closing valve.
15. An air conditioner comprising: at least one indoor unit; an
outdoor unit communicating with the indoor unit and having at least
one compressor and a plurality of heat exchange units in which the
refrigerant branches off and flows and performing heat exchange and
a header having branch fluid paths through which the refrigerant
can branch off and be supplied to the heat exchange units and a
distributor connected with the heat exchange units; a fluid path
opening/closing valve are installed on the upstream side of the
header for opening or closing a fluid path through which a
refrigerant can flow to the header; and a control unit for
controlling the compressor and the fluid path opening/closing valve
to perform appropriate compression and condensation of the
refrigerant according to the load amount of the indoor unit.
16. The air conditioner of claim 15, further comprising: a branch
fluid path opening/closing valve for opening or closing the branch
fluid path.
17. The air conditioner of claim 16, wherein the branch fluid path
comprises: an upstream branch fluid path for connecting the header
with the heat exchange units; and a downstream fluid path for
connecting the heat exchange units and the distributor, wherein the
branch fluid path opening/closing valve is installed at either the
upstream branch fluid path or the downstream branch fluid path.
18. The air conditioner of claim 16, wherein the branch fluid path
comprises: an upstream branch fluid path through which the header
is connected with the heat exchange units; and a downstream fluid
path through which the heat exchange units are connected with the
distributor, wherein the branch fluid path opening/closing valves
are installed at both the upstream branch fluid path and the
downstream branch fluid path.
19. The air conditioner of claim 16, wherein the control unit,
according to the load amount obtained by calculating the load when
some indoor units are operated, controls the compressors such that
some compressors are operated or the compressors are operated at
low frequencies, and opens or closes the fluid path opening/closing
valve and the branch fluid path opening/closing valve.
20. The air conditioner of claim 16, wherein the outdoor unit
comprises a main outdoor unit and a sub-outdoor unit connected and
installed in parallel.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an air conditioner, and
particularly, to an air conditioner capable of appropriately
maintaining a high pressure of a cycle during small-load
operation.
[0003] 2. Description of the Background Art
[0004] An air conditioner is for adjusting temperature, humidity,
air current and cleanliness of air in order to create a pleasant
indoor environment. According to the unit construction, there are
an integral type air conditioner in which an indoor unit and an
outdoor unit are received inside one single case and a separated
type air conditioner in which a compressor and a condenser as an
indoor unit are separated from an evaporator as an outdoor
unit.
[0005] An air conditioner for both heating and cooling, which is
part of the air conditioner, is provided with a fluid path switch
valve and switches a fluid path of a refrigerant to thereby
selectively perform its cooling or heating function. Recently, the
use of the so-called multi-type air conditioner having a plurality
of indoor units capable of cooling or heating according to indoor
spaces has been increasing.
[0006] In the multi-type air conditioner, a plurality of outdoor
units having a plurality of compressors and a plurality of outdoor
heat exchangers are connected to each other in parallel.
[0007] FIG. 1 is a schematic view of a conventional multi-type air
conditioner. With reference to FIG. 1, a conventional multi-type
air conditioner includes: a plurality of indoor units 10 having
indoor heat exchangers 11 and indoor expansion devices 13, and a
plurality of outdoor units 20 having outdoor heat exchangers 41 and
compressors 23. With the construction of FIG. 1, the outdoor units
20 supply the compressed refrigerant to each of the indoor units 10
via a pipe 30 and cool spaces where the indoor units 10 are
installed.
[0008] Meanwhile, the multi-air conditioner performs condensation
by using the outdoor heat exchangers 41 of all the outdoor units 20
even when some indoor units 10 perform cooling operations. As a
result, a condenser which is large in comparison to the area and
air flow of the heat exchangers corresponding to the indoor unit 10
load is used. Accordingly, a phenomenon that the system high
pressure decreases occurs.
[0009] When the phenomenon that the system high pressure decreases
occurs, a difference between a high pressure and a low pressure is
reduced and therefore the refrigerant cannot be smoothly supplied
to the indoor units 10 when the pipe 30 for connecting the indoor
units 10 and the outdoor units 20 to each other is long or when a
difference in altitude between the indoor units 10 and the outdoor
units 20 is great. In addition, since the lower pressure decreases
simultaneously when the high pressure of the system decreases, the
pipe of the indoor units 10 can be frozen. In particular, such a
phenomenon frequently occurs at low outdoor temperature.
[0010] Accordingly, the refrigerant cannot be smoothly supplied to
the indoor units 10 and the pipe of the indoor units 10 is frozen.
Thus, cooling or heating is impossible.
BRIEF DESCRIPTION OF THE INVENTION
[0011] Therefore, an object of the present invention is to provide
an air conditioner capable of appropriately maintaining a high
pressure of a cycle during small-load operation.
[0012] To achieve these and other advantages and in accordance with
the purpose of the present invention, as embodied and broadly
described herein, there is provided an air conditioner comprising:
at least one indoor unit; an outdoor unit communicating with the
indoor unit and having at least one compressor and one outdoor heat
exchanger; a fluid path opening/closing valve for opening or
closing a fluid path through which a refrigerant can flow to the
outdoor heat exchanger; and a control unit for controlling the
compressor and the fluid path opening/closing valve to perform
appropriate compression and condensation of the refrigerant
according to the load amount of the indoor unit.
[0013] The foregoing and other objects, features, aspects and
advantages of the present invention will become more apparent from
the following detailed description of the present invention when
taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The accompanying drawings, which are included to provide a
further understanding of the invention and are incorporated in and
constitute a part of this specification, illustrate embodiments of
the invention and together with the description serve to explain
the principles of the invention.
[0015] In the drawings:
[0016] FIG. 1 is a schematic view of a conventional multi-type air
conditioner;
[0017] FIG. 2 is a construction view of an air conditioner in
accordance with a first embodiment of the present invention;
[0018] FIG. 3 is a control block diagram of FIG. 2;
[0019] FIG. 4 is a construction view of an air conditioner in
accordance with a second embodiment of the present invention;
[0020] FIG. 5 is a construction view showing an important part of
an air conditioner in accordance with a third embodiment of the
present invention;
[0021] FIG. 6 is a control block diagram of FIGS. 4 and 5;
[0022] FIG. 7 is a construction view of an air conditioner in
accordance with a fourth embodiment of the present invention;
and
[0023] FIG. 8 is a control block diagram of FIG. 7.
DETAILED DESCRIPTION OF THE INVENTION
[0024] Hereinafter, an air conditioner in accordance with one
embodiment of the present invention will be described in detail
with reference to the accompanying drawings. FIG. 2 is a
construction view of an air conditioner in accordance with a first
embodiment of the present invention, and FIG. 3 is a control block
diagram of FIG. 2. For reference, a construction showing the same
operation and effect as the aforementioned and illustrated
construction will be given the same reference numerals, and a
description therefor will be omitted.
[0025] With reference to FIGS. 2 and 3, an air conditioner in
accordance with the first embodiment includes an indoor unit 10, an
outdoor unit 20, a fluid path opening/closing valve 55 and a
control unit 51.
[0026] Each of the indoor units 10 is disposed indoors, and
includes an indoor heat exchanger 11, a cooling fan (not
illustrated) disposed to promote heat exchange of the indoor heat
exchanger 11 and an indoor expansion device 13 disposed at one side
of the indoor heat exchanger 11 so as to expand a refrigerant.
[0027] The outdoor unit 20 includes compressors 23 for compressing
a refrigerant and a pair of outdoor heat exchangers 41 and 41'
connected with the compressors 23.
[0028] The compressors 23 are connected to each other via a flow
pipe 25 through which oil can flow, and each of the compressors 23
has an oil separator 27 and a check valve 29 at its discharge
side.
[0029] The downstream side of the check valves 29 along the
direction of the refrigerant flow join together at a confluence
junction. A four-way valve 31 is installed on the downstream side
of the confluence junction so as to switch a fluid path of the
refrigerant.
[0030] Each port of the four-way valve 31 communicates with each
one end of connection pipes 33 connected with the indoor heat
exchangers 41 and 41', an accumulator 35 and the indoor unit 10,
respectively.
[0031] Check valves 43 and outdoor expansion devices 45 are
provided on the downstream side of the outdoor heat exchangers 41
and 41', respectively, along the direction of the refrigerant
flow.
[0032] The fluid path opening/closing valve 55 is disposed on the
upstream side of the outdoor heat exchanger 41' along the direction
of the refrigerant flow. The fluid path opening/closing valve 55
blocks the fluid path of the refrigerant during small-load
operation, and comprises an electric valve such as solenoid in
order to allow the control by an electric signal.
[0033] The control unit 51 is implemented in the form of MICOM
having a control program therein and is electrically connected with
the compressors 23 and the fluid path opening/closing valve 55. The
control unit 51 calculates the load during small-load operation by
which some indoor units 10 are operated, and appropriately controls
compression and condensation on the basis of the calculated
load.
[0034] Hereinafter, the operation of an air conditioner illustrated
in FIGS. 2 and 3 will be described.
[0035] When some indoor units 10 are operated, the control unit 51
calculates the cooling or heating load. Of course, the control unit
51 can calculate the cooling or heating load when all the indoor
units 10 are operated.
[0036] According to the calculated cooling or heating load, the
control unit 51 control the compressors 23 such that some
compressors 23 are operated or the compressors 23 are operated at
low frequencies.
[0037] In addition, the control unit 51 controls the fluid path
opening/closing valve 55 such that the compressed refrigerant flows
or does not flow to the outdoor heat exchanger 41'. The compressors
23 and the fluid path opening/closing 55 can be simultaneously or
sequentially controlled as occasion demands.
[0038] Accordingly, the air conditioner having the construction of
FIGS. 2 and 3 can perform condensation corresponding only to the
amount of the indoor unit 10 load when some indoor units 10 perform
cooling or heating operation, so that a decrease of the system high
pressure does not occur.
[0039] FIG. 4 is a construction view of an air conditioner in
accordance with a second embodiment, FIG. 5 is a construction view
illustrating an important part of an air conditioner in accordance
with a third embodiment, and FIG. 6 is a control block diagram of
FIGS. 4 and 5.
[0040] With reference to FIG. 4, an air conditioner in accordance
with a second embodiment includes an indoor unit 10, an outdoor
unit 20, a fluid path opening/closing valve 55, a branch fluid path
opening/closing valve 49 and a control unit 51.
[0041] Since the indoor unit 10 has the same construction and
operation as the indoor unit 10 described in the first embodiment,
a description therefor will be omitted.
[0042] The outdoor unit 20 includes compressors 23 for compressing
a refrigerant and outdoor heat exchangers 41 and 41' connected with
the compressors 23.
[0043] Since the compressor 23 has the same construction and
operation as the compressor 23 described in the first embodiment, a
description therefor will be omitted.
[0044] In order that the optimum amount of refrigerant can flow,
the outdoor heat exchangers 41 and 41' include a plurality of heat
exchange units 42 separated from each other; headers 47 having
branch fluid paths through which the refrigerant branches off and
is supplied to each of the heat exchange units 42; and distributors
57, respectively.
[0045] The branch fluid path includes a plurality of upstream
branch fluid paths 48 for connecting the header 47 with the heat
exchange unit 42, and a plurality of downstream branch fluid paths
58 for connecting the heat exchange unit 42 with the distributor
57.
[0046] The fluid path opening/closing valve 55 is installed on the
upstream side of the header 47 of the outdoor heat exchanger 41',
and opens or closes the corresponding fluid path.
[0047] The branch fluid path opening/closing valve 49 is installed
on the upstream branch path 48 of the outer heat exchanger 41, and
opens or closes the upstream branch fluid path 48 along the
direction of the refrigerant flow.
[0048] FIG. 5 illustrates an air conditioner according to a third
embodiment in which a location where the branch fluid path
opening/closing valve 49 is installed is changed from the upstream
branch fluid path 48 of FIG. 4 to the downstream branch fluid path
58. With reference to FIG. 5, the branch fluid path opening/closing
valve 49 opens or closes the downstream branch fluid path 58. Of
course, the branch fluid path opening/closing valves 49 can be
installed at both the upstream branch fluid path 48 and the
downstream branch fluid paths 58.
[0049] With reference to FIG. 6, the control 51 is implemented as
MICOM having a control program therein, and is electrically
connected with the compressors 23, the fluid path opening/closing
valve 55 and the branch fluid path opening/closing valve 59. The
control unit 51 calculates the load during small-load operation by
which some indoor units 10 are operated. On the basis of the
calculated load, the control unit 51 appropriately controls
compression and condensation of the refrigerant.
[0050] Hereinafter, the operation of the air conditioner
illustrated in FIGS. 4 to 6 will be described.
[0051] When some indoor units 10 perform cooling operations, the
control unit 51 calculates the cooing or heating load. Of course,
if all the indoor units 10 perform cooling operations, the control
unit 51 can calculate the cooling or heating load.
[0052] According to the calculated cooling or heating load, the
control unit 51 controls the compressors 23 such that some
compressors 23 are operated or the compressors 23 are operated at
low frequencies.
[0053] In addition, the control unit 51 controls the fluid path
opening/closing valve 55 such that the compressed refrigerant flows
or does not flow to the outdoor heat exchanger 41'.
[0054] In addition, the control unit 51 controls the branch fluid
path opening/closing valve 49 such that the compressed refrigerant
flows or does not flow to the outdoor heat exchanger 41.
[0055] The compressors 23, the fluid path opening/closing valve 55
and the branch fluid path opening/closing valve 49 can be
simultaneously or sequentially controlled as occasion demands.
[0056] Accordingly, the air conditioner having the construction of
FIGS. 4 to 6 can perform condensation corresponding to the amount
of the indoor unit 10 load when some indoor units 10 perform
cooling or heating operation, so that the decrease of the system
high pressure does not occur.
[0057] FIG. 7 is a construction view of an air conditioner in
accordance with a fourth embodiment of the present invention and
FIG. 8 is a control block diagram of FIG. 7. With reference to
FIGS. 7 and 8, the air conditioner in accordance with the fourth
embodiment includes an indoor unit 10, an outdoor unit 20, a fluid
path opening/closing valve 55, a branch fluid path opening/closing
valve 59 and a control unit 51.
[0058] Since the indoor unit 10 has the same construction and
operation as the indoor unit described in the first embodiment, a
description therefor will be omitted.
[0059] The outdoor unit 20 includes a main outdoor unit 21a and a
sub-outdoor unit 21b connected and installed in parallel.
[0060] The main outdoor unit 21a and the sub-outdoor unit 21b
include a plurality of compressors 23, a plurality of outdoor heat
exchangers 41 and 41' and accumulators 35 and four-way valves 31,
respectively.
[0061] Oil separators 27 and check valves 29 are installed at
discharge sides of the compressors 23 of the main outdoor unit 21a
and the sub-outdoor unit 21b, respectively.
[0062] A pressure equalizing pipe 15 is provided between the main
outdoor unit 21a and the sub-outdoor unit 21b so as to allow the
upstream side of the outdoor heat exchangers 41 and 41' of the main
outdoor unit 21a and the upstream side of the outdoor heat
exchangers 41 and 41' of the sub-outdoor unit 21b to communicate
with each other along the direction of the refrigerant flow.
[0063] The fluid path opening/closing valves 55 are installed on
the upstream side of the outdoor heat exchanger 41 and 41' of the
main outdoor unit 21a and on the upstream of the outdoor heat
exchangers 41 and 41' of the sub-outdoor unit 21b, respectively, so
as to open or close the corresponding fluid path along the
direction of the refrigerant flow.
[0064] The branch fluid path opening/closing valve 59 is installed
at the downstream branch fluid path 58 of the outdoor heat
exchanger 41 of the main outdoor unit 21a so as to open or close
the corresponding branch fluid path 58.
[0065] With reference to FIG. 8, the control unit 51 is implemented
in the form of MICOM having a control program therein, and is
electrically connected with the compressors 23, the fluid path
opening/closing valve 55 and the branch fluid path opening/closing
valve 59.
[0066] The control unit 51 calculates the load during small-load
operation by which some indoor units 10 are operated and
appropriately controls compression and condensation on the basis of
the calculated load.
[0067] Hereinafter, the operation of the air conditioner
illustrated in FIGS. 7 and 8 will be described.
[0068] When some indoor units 10 perform cooling operations, the
control unit 51 calculates the cooling or heating load. Of course,
when all the indoor units 10 perform cooling operations, the
control unit 51 can calculate the cooling or heating load.
[0069] According to the calculated cooling or heating load, the
control unit 51 controls the compressors 23 such that some
compressors 23 are operated or the compressors 23 are operated at
low frequencies.
[0070] In addition, the control unit 51 controls the fluid path
opening/closing valve 55 such that the compressed refrigerant can
flow or cannot flow to the outdoor heat exchanger 41 and 41' of the
main outdoor unit 21a and to the outdoor heat exchangers 41 and 41'
of the sub-outdoor unit 21b.
[0071] In addition, the control unit 51 controls the branch fluid
path opening/closing path 49 such that the compressed refrigerant
can flow or cannot flow to the outdoor heat exchanger 41 of the
main outdoor unit 21a.
[0072] The compressor 23, the fluid path opening/closing valve 55
and the branch fluid path opening/closing valve 59 can be
simultaneously or sequentially controlled as occasion demands.
[0073] Accordingly, the air conditioner having the construction of
FIGS. 4 to 6 can perform condensation corresponding to the amount
of the indoor unit 10 load when some indoor units 10 perform
cooling or heating operation, so that the decrease of the system
high pressure does not occur.
[0074] The air conditioner in accordance with one embodiment of the
present invention of which description has been made so far
includes the fluid path opening/closing valve and the branch fluid
path opening/closing valve which are capable of opening or closing
fluid paths and a control unit for controlling the valves.
Accordingly, even during the small-load operation, a high pressure
of a cycle is appropriately maintained to thusly increase
reliability in operation.
[0075] 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.
* * * * *