U.S. patent application number 11/750245 was filed with the patent office on 2007-11-22 for air conditioner and method of controlling the same.
This patent application is currently assigned to LG ELECTRONICS INC.. Invention is credited to Seung Youp HYUN, Ji Young JANG, Seung Woo KANG, Chan Ho SONG.
Application Number | 20070266719 11/750245 |
Document ID | / |
Family ID | 38710729 |
Filed Date | 2007-11-22 |
United States Patent
Application |
20070266719 |
Kind Code |
A1 |
KANG; Seung Woo ; et
al. |
November 22, 2007 |
AIR CONDITIONER AND METHOD OF CONTROLLING THE SAME
Abstract
An air conditioner includes first and second compressors, an
outdoor heat exchanger through which refrigerant discharged from
the first and second compressors passes, an outdoor fan for
forcedly directing air toward the outdoor heat exchanger, an
expansion valve for expanding the refrigerant discharged from the
outdoor heat exchanger, an indoor heat exchanger through which the
refrigerant expanded in the expansion valve passes, a linear
expansion valve for adjust a flow rate of the refrigerant, a load
detecting unit for deterring an indoor load, and a control unit for
controlling the operation of the first and second compressors in
accordance with the detected indoor load. In a state where the
second compressor is not driven, the control unit allows the second
compressor to drive when a driving start conditioner of the second
compressor is satisfied and a driving start retarding time has been
elapsed. The control unit adjusts an opening of the linear
expansion valve and an operation of the outdoor fan for the driving
start retarding time.
Inventors: |
KANG; Seung Woo; (Seoul,
KR) ; JANG; Ji Young; (Seongnam-si, KR) ;
SONG; Chan Ho; (Goyang-si, KR) ; HYUN; Seung
Youp; (Seoul, KR) |
Correspondence
Address: |
WORKMAN NYDEGGER
60 EAST SOUTH TEMPLE
1000 EAGLE GATE TOWER
SALT LAKE CITY
UT
84111
US
|
Assignee: |
LG ELECTRONICS INC.
Seoul
KR
|
Family ID: |
38710729 |
Appl. No.: |
11/750245 |
Filed: |
May 17, 2007 |
Current U.S.
Class: |
62/228.5 ;
62/183 |
Current CPC
Class: |
Y02B 30/70 20130101;
F25B 2600/01 20130101; F24F 2110/00 20180101; F25B 2600/021
20130101; F25B 2600/111 20130101; F24F 11/30 20180101; F25B 49/022
20130101; F25B 2400/075 20130101; F25B 2500/26 20130101; F25B
2600/2513 20130101 |
Class at
Publication: |
062/228.5 ;
062/183 |
International
Class: |
F25B 39/04 20060101
F25B039/04; F25B 49/00 20060101 F25B049/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 20, 2006 |
KR |
10-2006-0045421 |
Claims
1. A method of controlling an air conditioner, comprising: driving
a first compressor among a plurality of compressors; determining if
a driving start condition of the second compressor is satisfied
during driving of the first compressor; and adjusting, when the
driving start condition of the second compressor is satisfied, at
least one of discharge and intake pressures of the second
compressor for a driving start retarding time such that a
difference between the discharge and intake pressures is less than
a predetermined value.
2. The method according to claim 1, wherein one of the first and
second compressors is an inverter compressor and the other is a
constant compressor.
3. The method according to claim 1, wherein the driving start
retarding time is a time measured after only the first compressor
is driven.
4. The method according to claim 1, wherein the discharge pressure
of the second compressor is reduced for the driving start retarding
time of the second compressor.
5. The method according to claim 4, wherein a linear expansion
valve is fully opened for a first reference time to reduce the
discharge pressure of the second compressor.
6. The method according to claim 5, wherein the opening of the
linear expansion valve is returned to an initial state when the
first reference time has been elapsed.
7. The method according to claim 1, wherein the intake pressure
increases for the driving start retarding time of the second
compressor.
8. The method according to claim 7, wherein an outdoor fan is
stopped for a second reference time in order to increase the intake
pressure of the second compressor.
9. The method according to claim 8, wherein the outdoor fan starts
operating after the second reference time has been elapsed.
10. The method according to claim 1, wherein the discharge pressure
of the second compressor is reduced for the driving start retarding
time while the intake pressure of the second compressor increases
for the driving start retarding time.
11. The method according to claim 10, wherein the reduction of the
discharge pressure and the increase of the intake pressure are
sequentially realized.
12. The method according to claim 11, wherein a linear expansion
valve for adjusting a flow rate of the refrigerant is fully opened
for a first reference time to reduce the discharge pressure of the
second compressor and an outdoor fan is stopped for a second
reference time in order to increase the intake pressure of the
second compressor.
13. The air conditioner according to claim 12, further comprising
driving the second compressor after the driving start retarding
time has been elapsed.
14. A method of controlling an air conditioner, comprising:
stopping driving of a first compressor during driving of a
plurality of compressors; determining if a driving start condition
of the first compressor is satisfied; and driving, when the driving
start condition is satisfied, the first compressor after a driving
start retarding condition has been elapsed, wherein a discharge
pressure of the first compressor is forcedly reduced for the
driving start retarding time or an intake pressure of the first
compressor is forcedly increased for the driving start retarding
time.
15. The method of claim 14, wherein a linear expansion valve for
adjusting a flow rate of the refrigerant is fully opened for a
first reference time to reduce the discharge pressure of the second
compressor.
16. The method according to claim 15, wherein the opening of the
linear expansion valve is returned to an initial state when the
first reference time has been elapsed.
17. The method according to claim 16, wherein driving of an outdoor
fan is stopped for a second reference time after the opening of the
linear expansion valve is returned to the initial state.
18. The method according to claim 17, wherein the outdoor fan
starts driving after the second reference time has been
elapsed.
19. An air conditioner comprising: first and second compressors; an
outdoor heat exchanger through which refrigerant discharged from
the first and second compressors passes; an outdoor fan for
forcedly directing air toward the outdoor heat exchanger; an
expansion valve for expanding the refrigerant discharged from the
outdoor heat exchanger; an indoor heat exchanger through which the
refrigerant expanded in the expansion valve passes; a linear
expansion valve for adjust a flow rate of the refrigerant; a load
detecting unit for deterring an indoor load; and a control unit for
controlling the operation of the first and second compressors in
accordance with the detected indoor load, wherein, in a state where
the second compressor is not driven, the control unit allows the
second compressor to drive when a driving start conditioner of the
second compressor is satisfied and a driving start retarding time
has been elapsed; and the control unit adjusts an opening of the
linear expansion valve or an operation of the outdoor fan for the
driving start retarding time.
20. The air conditioner according to claim 19, wherein the linear
expansion valve is fully opened for a first reference time within a
range of the driving start retarding time and the outdoor fan is
stopped for a second reference time within a range of the driving
start retarding time.
Description
[0001] The present application claims priority under 25 U.S.C. 119
and 35 U.S.C. 365 to Korean Patent Application No. 10-2006-0045421
(field on May 20, 2006), which is hereby incorporated by reference
in its entirety.
BACKGROUND
[0002] 1. Field
[0003] This disclosure relates to an air conditioner and a
controlling method thereof.
[0004] 2. Description of the Related Art
[0005] Generally, an air conditioner is an electronic appliance
that maintains indoor air at a most proper state in accordance with
use and purpose. For example, the air conditioner allows the indoor
air to be in a cool state in summer and allows the indoor air to be
in a hot state in winter. Further, the air conditioner controls a
humidity of the indoor space and purifies the air by removing
impurities from the air.
[0006] The air conditioners are classified into split type air
conditioners where indoor and outdoor units are separated from each
other and integral type air conditioners where the indoor and
outdoor units are integrally coupled to each other.
[0007] Meanwhile, the air conditioner includes a compressor for
compressing refrigerant, an outdoor unit, an expansion valve, and
an indoor heat exchanger, thereby forming one cycle. Recently, a
plurality of compressors having different volumes have been used to
vary the compression volume in accordance with indoor load.
[0008] That is, in the air conditioner having two compressors
(first and second compressors) having different volumes, only one
of the first and second compressors is used when the indoor load is
relatively low and both of the first and second compressors are
used when the indoor load is relatively high.
[0009] Further, when the indoor load is reduced in a state where
both of the compressors are operating due to the high indoor load,
one of the compressors is not driven. In this state, when the
indoor load increases again, the stopped compressor is driven
again. That is, both of the compressors are driven.
SUMMARY
[0010] An implementation of an air conditioner includes a plurality
of compressors that are selectively driven in accordance with the
indoor load.
[0011] When it is intended to driving start a stopped compressor,
the stopped compressor starts operating after a predetermined
driving start retarding time has been elapsed. Discharge and intake
pressures of the stopped compressor are adjusted for the
predetermined driving start retarding time.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a view illustrating an operational cycle of an air
conditioner;
[0013] FIG. 2 is a block diagram illustrating a control method of
an air conditioner; and
[0014] FIG. 3 is a flowchart illustrating a control method of an
air conditioner.
DETAILED DESCRIPTION
[0015] FIG. 1 is a view illustrating an operational cycle of an air
conditioner.
[0016] Referring to FIG. 1, an air conditioner includes compressors
12 and 14 for compressing refrigerant an outdoor heat exchanger 30
for condensing the refrigerant compressed in the compressors 12 and
14, an expansion valve 50 for expanding the refrigerant condensed
in the outdoor heat exchanger 30, and an indoor heat exchanger 60
for converting the refrigerant expanded by the expansion valve 50
into gas-phased refrigerant.
[0017] An outdoor fan 32 is provided at the outdoor heat exchanger
30 and an indoor fan 62 is provided at the indoor heat exchanger
60.
[0018] In addition, a linear expansion valve 40 is provided at an
outlet side of the outdoor heat exchanger 30.
[0019] In more detail, the compressors 12 and 14 are selectively
operated to vary the capacity of the air conditioner in accordance
with the indoor load. The compressors 12 and 14 will be
respectively referred to as first and second compressors.
[0020] Here, the first compressor 12 may be an inverter compressor
whose capacity is variable. The second compressor 14 may be a
constant compressor that operates constantly.
[0021] Therefore, when the indoor load is relatively low, only the
first compressor 12 is driven. Subsequently, when the indoor load
increases to be higher than the capacity of the first compressor
12, the second compressor 14 is additionally driven. Alternatively,
when the indoor load is relatively low, only the second compressor
14 is driven. Subsequently, when the indoor load increases to be
higher than the capacity of the second compressor 14, the first
compressor 12 may be additionally driven.
[0022] In the present embodiment, a case where the first compressor
12 is firstly driven and subsequently the second compressor 14 is
additionally driven in accordance with the indoor load.
[0023] With the above structure of the air conditioner, when the
air conditioner operates with a cooling mode, the refrigerant
discharged from the indoor heat exchanger 60 is directed into the
compressors 12 and 14 and compressed therein. The refrigerant
compressed in the compressors 12 and 14 flows inside of the outdoor
heat exchange 30 to heat-exchange with an external air.
[0024] The refrigerant passing through the outdoor heat exchanger
30 is pressure-reduced while passing through the expansion valve
50. At this point, an amount of the refrigerant directed to the
expansion valve 50 varies in accordance with an opening of the
linear expansion valve 40.
[0025] The refrigerant that is pressure-reduced while passing
through the expansion valve 50 heat-exchanges with indoor air while
passing through the indoor heat exchanger 60. The indoor heat
exchanger 60 passing through the indoor heat exchanger 60 is
directed to the compressors 12 and 14 again, thereby completing a
cooling cycle of the air conditioner.
[0026] The indoor load may vary during the operation of the air
conditioner. When the indoor load is relatively low, only the first
compressor 12 operates.
[0027] In a state where only the first compressor 12 operates, when
the indoor load increases to be higher than the capacity of the
first compressor 12, the operation of the second compressor 14 is
required.
[0028] At this point, the second compressor 14 starts operating
after an driving start retarding time, e.g., 10 minutes, has been
elapsed from the stopping of the operation.
[0029] That is, in order to prevent the operation failure of the
second compressor 14, the second compressor starts operating after
a difference between an intake pressure and a discharge pressure of
the second compressor is less than a predetermined value.
[0030] Here, when the driving start of the second compressor 14 is
required before the driving start retarding time has been elapsed
from the stopping state, the second compressor 14 starts operating
after the driving start retarding time has been elapsed. When the
driving start of the second compressor 14 is required after the
driving start retarding time has been elapsed from the stopping
state, the second compressor 14 immediately starts operating.
[0031] However, even when there is the driving start retarding
time, the difference between the discharge pressure and the intake
pressure of the second compressor is not less than a predetermined
value, e.g., 0.2 bar, there may be a driving start failure of the
second compressor.
[0032] Therefore, in order to prevent the driving start failure of
the second compressor, it is preferable that the difference between
the exhaust and intake pressures is forcedly reduced to be less
than the predetermined value before the driving start retarding
time has been elapsed.
[0033] The following will describe a method for preventing the
driving start failure of the second compressor 14 in more
detail.
[0034] FIG. 2 is a block diagram illustrating a control method of
an air conditioner according to an embodiment of the present
invention, and FIG. 3 is a flowchart illustrating a control method
of an air conditioner according to an embodiment of the present
invention.
[0035] Referring to FIG. 3, the air conditioner of this embodiment
includes a load detecting unit 210 for detecting the indoor load, a
control unit 200 for controlling the operation of the compressors
12 and 14 in accordance with the detected indoor load, a timer 220
for counting the driving start retarding time of the second
compressor 14, and a driving unit 230 for driving the outdoor fan
32 and the linear expansion valve 40 in accordance with the control
of the control unit 200.
[0036] The control unit 200 controls the operation of the outdoor
fan 32 as the driving start retarding time passes and further
controls the opening of the linear expansion valve 40.
[0037] The following will describe a control method of the air
conditioner that is structured as describe above.
[0038] When the user operates the air conditioner, the indoor load
is detected by the load detecting unit 210 and the compressors 12
and 14 are driven in accordance with the detected indoor load.
[0039] At this point, when the indoor load is relatively high, both
of the first and second compressors 12 and 14 are driven, in the
course of which, when the indoor load is reduced to a predetermined
level, the driving of the second compressor 14 is stopped and the
first compressor operated (S1).
[0040] When the indoor load increases again to satisfy the driving
start condition of the second compressor (S2), the second
compressor 14 is driven after a predetermined driving start
retarding time, e.g., 10 minutes, has elapsed. At this point, the
driving start retarding time is counted by the timer 220.
[0041] For example, when a first predetermined driving start
retarding time, e.g., 8.5 minutes, has elapsed, the control unit
200 fully opens the linear expansion valve 40 for a first reference
time, e.g., 15 seconds.
[0042] Then, since the flow rate of the refrigerant increases, the
discharge temperature of the second compressor 14 is reduced and
thus the discharge pressure of the second compressor 14 is
reduced.
[0043] When the first reference time has elapsed, the control unit
200 returns the linear expansion valve to an initial state
(S4).
[0044] Next, when a second predetermined driving start retarding
time, e.g., 9 minutes, has further elapsed, the driving of the
outdoor fan 32 is stopped for a second reference time, e.g., 10
seconds.
[0045] Then, the temperature of the refrigerant passing through the
outdoor heat exchanger 30 increases and thus the condensing
pressure increases. As a result, the intake pressure of the second
compressor 14 increases.
[0046] When the second reference time has elapsed, the driving of
the outdoor fan 32 is stopped (S6).
[0047] Subsequently, when the driving start retarding time has
elapsed (S7), the second compressor 14 is driven (S8).
[0048] Therefore, the discharge pressure of the second compressor
is forcedly reduced and the intake pressure of the second
compressor forcedly increases. As a result, the difference between
the discharge and intake pressures becomes less than a
predetermined value. Therefore, when the driving start condition of
the second compressor is satisfied, the second compressor can be
driven immediately after the driving start retarding time has
elapsed.
[0049] Here, in the present embodiment, the discharge pressure of
the second compressor 14 is reduced before the intake pressure of
the second compressor 14 increases. However, the present invention
is not limited to this embodiment. For example, the intake pressure
of the second compressor 14 is reduced before the discharge
pressure of the second compressor 14 increases.
* * * * *