U.S. patent application number 14/567001 was filed with the patent office on 2015-06-18 for cooling apparatus.
This patent application is currently assigned to SAMSUNG ELECTRONICS CO., LTD.. The applicant listed for this patent is SAMSUNG ELECTRONICS CO., LTD.. Invention is credited to Hee Moon JEONG, Seong Ho KIL, Byung Moo LEE.
Application Number | 20150168024 14/567001 |
Document ID | / |
Family ID | 53367970 |
Filed Date | 2015-06-18 |
United States Patent
Application |
20150168024 |
Kind Code |
A1 |
LEE; Byung Moo ; et
al. |
June 18, 2015 |
COOLING APPARATUS
Abstract
A cooling cycle includes a first refrigerant circuit, a second
refrigerant circuit and the third refrigerant circuit and switches
the refrigerant circulation between the refrigerant circuits
according to cooling modes so that a plurality of evaporators is
efficiently controlled and Coefficient of Performance (COP) is
improved by including an ejector.
Inventors: |
LEE; Byung Moo; (Seoul,
KR) ; JEONG; Hee Moon; (Yongin-si, KR) ; KIL;
Seong Ho; (Seongnam-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SAMSUNG ELECTRONICS CO., LTD. |
Suwon-si |
|
KR |
|
|
Assignee: |
SAMSUNG ELECTRONICS CO.,
LTD.
Suwon-si
KR
|
Family ID: |
53367970 |
Appl. No.: |
14/567001 |
Filed: |
December 11, 2014 |
Current U.S.
Class: |
62/117 ;
62/511 |
Current CPC
Class: |
F25B 2700/02 20130101;
F25B 2400/0409 20130101; F25B 2341/0012 20130101; F25B 2600/2519
20130101; F25B 2600/0251 20130101; F25B 2600/0253 20130101; Y02B
30/70 20130101; F25B 2600/112 20130101; F25B 2700/2104 20130101;
F25B 2500/06 20130101; F25D 21/006 20130101; F25B 2500/28 20130101;
F25B 2400/06 20130101; Y02B 30/743 20130101; F25B 2400/23 20130101;
F25B 2500/19 20130101; F25B 2600/2507 20130101; F25B 2500/14
20130101; F25B 2600/23 20130101; F25D 21/08 20130101; F25B 49/02
20130101; F25B 2341/0011 20130101; Y02B 30/741 20130101; F25B
2341/0661 20130101; F25B 2400/054 20130101; F25B 5/04 20130101;
F25B 41/00 20130101; F25B 2400/052 20130101; F25B 2700/2117
20130101 |
International
Class: |
F25B 5/00 20060101
F25B005/00; F25B 49/02 20060101 F25B049/02 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 12, 2013 |
KR |
10-2013-0154692 |
Claims
1. A cooling apparatus comprising: a first refrigerant circuit
configured to allow a refrigerant discharged from a compressor to
flow to a suction side of the compressor by passing through a
condenser, an ejector, and a vapor liquid separator; a second
refrigerant circuit configured to allow the refrigerant to be
sucked into an inlet of the ejector to be circulated by passing
through the ejector, the vapor liquid separator, a first expansion
device, a first evaporator and a second evaporator; and a third
refrigerant circuit configured to allow the refrigerant passing
through the ejector and the vapor liquid separator to be sucked
into an inlet of the ejector by passing through a second expansion
device and the second evaporator to bypass the first expansion
device and the first evaporator, wherein the ejector mixes a
refrigerant discharged from the condenser in the first refrigerant
circuit with a refrigerant discharged from the second evaporator to
discharge to the vapor liquid separator.
2. The cooling apparatus of claim 1, further comprising: a flow
path switching device installed on a portion of a discharge side of
the vapor liquid separator to allow a liquid refrigerant passing
through the vapor liquid separator to flow through at least one of
the second refrigerant circuit and the third refrigerant
circuit.
3. The cooling apparatus of claim 2, further comprising: a control
unit configured to control the flow path switching for a
refrigerant to flow through the second refrigerant circuit when
power supply is started and to flow through the third refrigerant
circuit when cooling through the second refrigerant circuit is
completed.
4. The cooling apparatus of claim 1, wherein the second refrigerant
circuit is configured to allow a refrigerant passing through the
first evaporator to pass through the second evaporator.
5. The cooling apparatus of claim 1, wherein the ejector mixes a
refrigerant discharged from the condenser and a refrigerant
discharged from the second evaporator, increases a pressure of the
mixed refrigerant, and discharges to the vapor liquid
separator.
6. The cooling apparatus of claim 1, wherein the vapor liquid
separator separates a refrigerant discharged from the ejector into
a vapor refrigerant and a liquid refrigerant, discharges the vapor
refrigerant to the first refrigerant circuit, and discharges the
liquid refrigerant to the second refrigerant circuit or the third
refrigerant circuit.
7. The cooling apparatus of claim 5, wherein the ejector comprises
a nozzle configured to decompress and expand a refrigerant
discharged from the condenser, a suction unit configured to suction
a refrigerant discharged from the second evaporator, a mixing unit
configured to mix a refrigerant introduced to the nozzle and a
refrigerant introduced to the suction unit, and a diffuser
configured to raise a pressure of a refrigerant mixed in the mixing
unit.
8. The cooling apparatus of claim 1, wherein the compressor
comprises an inverter compressor configured to control the amount
of a refrigerant flow by controlling a rotation.
9. The cooling apparatus of claim 1, wherein the expansion device
comprises at least one of a capillary, an electronic expansion
valve and a capillary tube.
10. The cooling apparatus of claim 1, further comprising: a third
expansion device provided on a discharge unit of the condenser to
increase a humidity of a refrigerant introduced to the ejector.
11. The cooling apparatus of claim 10, further comprising: a
Suction Line Heat Exchanger (SLHX) configured to exchange heat
between the third expansion device and the suction unit of the
compressor.
12. The cooling apparatus of claim 1, wherein the first refrigerant
circuit further comprises a heat exchanger configured to exchange
heat between the discharge unit of the condenser and the suction
unit of the compressor.
13. The cooling apparatus of claim 1, wherein the second
refrigerant circuit further comprises an intermediate expansion
device provided on a discharge unit of the first evaporator to
decompress a refrigerant flowing in the second evaporator.
14. The cooling apparatus of claim 13, wherein an internal diameter
of the intermediate expansion device is smaller than an internal
diameter of a refrigerant pipe disposed on a suction side of the
compressor.
15. The cooling apparatus of claim 14, wherein the internal
diameter of the intermediate expansion device is approximately
2.about.4 mm.
16. A cooling apparatus comprising: a main refrigerant circuit
provided with a vapor liquid separator separating a refrigerant
into a vapor refrigerant and a liquid refrigerant, a compressor
compressing a refrigerant by introducing the vapor refrigerant
which is separated in the vapor liquid separator, and a condenser
condensing a refrigerant compressed by the compressor; an entire
cooling mode refrigerant circuit configured to pass through a first
expansion device, a first evaporator, and a second evaporator; a
freezing mode refrigerant circuit configured to pass through the
second expansion device and the second evaporator to bypass the
first expansion device and the first evaporator; a flow path
switching device configured to switch a flow path to allow a liquid
refrigerant introduced from the vapor liquid separator to flow
through at least one of the entire cooling mode refrigerant circuit
and the freezing mode refrigerant circuit; and an ejector
configured to mix a refrigerant, which is discharged from the
condenser in the main refrigerant circuit, and a refrigerant, which
is discharged from the second evaporator in at least one of the
entire cooling mode refrigerant circuit and the freezing mode
refrigerant circuit, to introduce to the vapor liquid
separator.
17. The cooling apparatus of claim 16, wherein the ejector mixes a
refrigerant discharged from the condenser and a refrigerant
discharged from the second evaporator, increases a pressure of the
mixed refrigerant, and discharges to the vapor liquid
separator.
18. A control method of a cooling apparatus having a first
refrigerant circuit configured to allow a refrigerant discharged
from a compressor to flow to a suction side of the compressor by
passing through a condenser, an ejector, and a vapor liquid
separator; a second refrigerant circuit configured to allow the
refrigerant to be sucked into an inlet of the ejector to circulate
by passing through the ejector, the vapor liquid separator, a first
expansion device, a first evaporator cooling a first cooling
compartment, and a second evaporator cooling a second cooling
compartment; a third refrigerant circuit configured to allow the
refrigerant passing through the vapor liquid separator to be sucked
into an inlet of the ejector by passing through a second expansion
device and the second evaporator to bypass the first expansion
device and the first evaporator, and a flow path switching device
installed on a portion of a discharge side of the vapor liquid
separator to switch a refrigerant flow to allow a liquid
refrigerant passing through the vapor liquid separator to pass
through at least one of the second refrigerant circuit and the
third refrigerant circuit, the control method comprising: cooling
the first and the second cooling compartments by controlling the
flow path switching device so that a refrigerant may flow through
the first refrigerant circuit and the second refrigerant circuit;
and cooling the second cooling compartment by controlling the flow
path switching device so that a refrigerant may flow through the
first refrigerant circuit and the third refrigerant circuit when a
temperature of the first cooling compartment reaches a target
temperature.
19. The control method of claim 18, wherein the amount of a
refrigerant flow in the entire cooling mode and the freezing mode
is adjusted by controlling the number of rotation of the compressor
when an operation through the first refrigerant circuit and the
second refrigerant circuit is referred to as an entire cooling
mode, and an operation through the first refrigerant circuit and
the third refrigerant circuit is referred to as a freezing
mode.
20. The control method of claim 18, wherein the first evaporator is
defrosted by supplying the compressed refrigerant discharged from
the compressor to the second refrigerant circuit by closing the
third refrigerant circuit and opening the second refrigerant
circuit by controlling the flow path switching device when driving
the compressor is stopped.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of Korean Patent
Application No. 10-2013-0154692, filed on Dec. 12, 2013 in the
Korean Intellectual Property Office, the disclosure of which is
incorporated herein by reference.
BACKGROUND
[0002] 1. Field
[0003] Embodiments of the present disclosure relate to a cooling
apparatus, more particularly a cooling apparatus having improved
Coefficient of Performance (COP).
[0004] 2. Description of the Related Art
[0005] A cooling apparatus having at least two cooling chambers
separated by a center partition is provided so that each cooling
chamber is opened/closed by a door. In addition, each cooling
chamber may have an evaporator generating cooling air and a fan
blowing the cooling air in to each chamber. All cooling chambers
may be independently refrigerated by each evaporator and each fan,
which is referred as a separate-cooling type. A representative
cooling apparatus having the separate-cooling type may be a
refrigerator provided with a refrigerating compartment and a
freezing compartment. The freezing compartment is to store frozen
food, and a proper temperature thereof may be about -18.degree. C.
Meanwhile, the refrigerating compartment is store general food,
which is stored at a cool temperature without requiring freezing,
and a proper temperature thereof may be about 3.degree. C.
[0006] As mentioned above, although the proper temperature of the
refrigerating compartment and the proper temperature of the
freezing compartment are different, evaporation temperatures of a
first evaporator and a second evaporator in conventional
refrigerators are the same. Because of this, a fan of the freezing
compartment is rotated continuously and a fan of the refrigerating
compartment is rotated intermittently as needed to blow cool air to
the refrigerating compartment so that a temperature of the
refrigerating compartment may be prevented from being lowered.
[0007] When it is required that the refrigerating compartment be
independently cooled, a load of a compressor may be increased
unnecessarily since a refrigerant is compressed corresponding to
the evaporation temperature required by the second evaporator.
SUMMARY
[0008] Therefore, it is an aspect of the present disclosure to
provide a cooling apparatus having an improved Coefficient of
Performance (COP).
[0009] Additional aspects of the present disclosure will be set
forth in part in the description which follows and, in part, will
be apparent from the description, or may be learned by practice of
the invention.
[0010] In accordance with one aspect of the present disclosure, a
cooling apparatus includes a first refrigerant circuit configured
to allow a refrigerant discharged from a compressor to flow to a
suction side of the compressor by passing through a condenser, an
ejector, and a vapor liquid separator; a second refrigerant circuit
configured to allow the refrigerant to be sucked into an inlet of
the ejector to be circulated by passing through the ejector, the
vapor liquid separator, a first expansion device, a first
evaporator and a second evaporator; and a third refrigerant circuit
configured to allow the refrigerant passing through the vapor
liquid separator to be sucked into an inlet of the ejector by
passing through a second expansion device and the second evaporator
to bypass the first expansion device and the first evaporator,
wherein the ejector may mix a refrigerant, which is discharged from
the condenser in the first refrigerant circuit, and a refrigerant,
which is discharged from the second evaporator in the second
refrigerant circuit or the third refrigerant circuit, to discharge
to the vapor liquid separator.
[0011] The cooling apparatus may include a flow path switching
device installed on a portion of a discharge side of the vapor
liquid separator to allow a liquid refrigerant passing through the
vapor liquid separator to flow through at least one of the second
refrigerant circuit and the third refrigerant circuit.
[0012] The cooling apparatus may include a control unit configured
to control a refrigerant flow by selectively opening or closing the
flow path switching device, wherein the control unit may control
the flow path switching so that a refrigerant may flow in the
second refrigerant circuit when power supply is started and a
refrigerant may flow in the third refrigerant circuit when cooling
through the second refrigerant circuit is completed.
[0013] The second refrigerant circuit may be configured to allow a
refrigerant passing through the first evaporator to pass through
the second evaporator.
[0014] The ejector may increase pressure of a refrigerant
discharged from the condenser and a refrigerant discharged from the
second evaporator, and discharge to the vapor liquid separator.
[0015] The vapor liquid separator may separate a refrigerant
discharged from the ejector into a vapor refrigerant and a liquid
refrigerant, may discharge the vapor refrigerant to the first
refrigerant circuit, and may discharge the liquid refrigerant to
the second refrigerant circuit or the third refrigerant circuit
[0016] The ejector may include a nozzle configured to decompress
and expand a refrigerant discharged from the condenser, a suction
unit configured to suction a refrigerant discharged from the second
evaporator, a mixing unit configured to mix a refrigerant
introduced to the nozzle and a refrigerant introduced to the
suction unit, and a diffuser configured to raise a pressure of a
refrigerant mixed in the mixing unit.
[0017] The compressor may include an inverter compressor configured
to control the amount of a refrigerant flow by controlling a
rotation.
[0018] The expansion device may include at least one of a
capillary, an electronic expansion valve and a capillary tube.
[0019] The cooling apparatus may further include a third expansion
device provided on a discharge unit of the condenser to increase a
humidity of a refrigerant introduced to the ejector.
[0020] The cooling apparatus may further include a Suction Line
Heat Exchanger (SLHX) configured to exchange heat between the third
expansion device and the suction unit of the compressor.
[0021] The first refrigerant circuit may further include a heat
exchanger configured to exchange heat between the discharge unit of
the condenser and the suction unit of the compressor.
[0022] The second refrigerant circuit may include an intermediate
expansion device provided on a discharge unit of the first
evaporator to decompress a refrigerant flowing in the second
evaporator.
[0023] An internal diameter of the intermediate expansion device
may be smaller than an internal diameter of a refrigerant pipe
disposed on a suction side of the compressor.
[0024] In accordance with one aspect of the present disclosure, a
cooling apparatus includes a main refrigerant circuit, an entire
cooling mode refrigerant circuit, a freezing mode refrigerant
circuit, a flow path switching device, and an ejector. The main
refrigerant circuit may include a vapor liquid separator separating
a refrigerant into a vapor refrigerant and a liquid refrigerant, a
compressor compressing a refrigerant by introducing the vapor
refrigerant, which is separated in the vapor liquid separator and a
condenser condensing a refrigerant compressed by the compressor.
The entire cooling mode refrigerant circuit may be configured to
pass through a first expansion device, a first evaporator, and a
second evaporator. The freezing mode refrigerant circuit may be
configured to pass through the second expansion device and the
second evaporator to bypass the first expansion device and the
first evaporator. The flow path switching device may be configured
to switch a flow path to allow a liquid refrigerant introduced from
the vapor liquid separator to flow through at least one of the
entire cooling mode refrigerant circuit and the freezing mode
refrigerant circuit. The ejector may mix a refrigerant, which is
discharged from the condenser in the main refrigerant circuit, and
a refrigerant, which is discharged from the second evaporator in at
least one of the entire cooling mode refrigerant circuit and the
freezing mode refrigerant circuit, to introduce to the vapor liquid
separator
[0025] The ejector may increase a pressure of a refrigerant
discharged from the condenser and a refrigerant discharged from the
second evaporator, and discharge to the vapor liquid separator.
[0026] In accordance with one aspect of the present disclosure, a
control method of a cooling apparatus provided with a first
refrigerant circuit configured to allow a refrigerant discharged
from a compressor to flow to a suction side of the compressor by
passing through a condenser, an ejector, and a vapor liquid
separator; a second refrigerant circuit configured to allow the
refrigerant to be sucked into an inlet of the ejector to be
circulated by passing through the ejector, the vapor liquid
separator, a first expansion device, a first evaporator cooling a
first cooling compartment, and a second evaporator cooling a second
cooling compartment; a third refrigerant circuit configured to
allow the refrigerant passing through the vapor liquid separator to
be sucked into an inlet of the ejector by passing through a second
expansion device and the second evaporator to bypass the first
expansion device and the first evaporator, and a flow path
switching device installed on a portion of a discharge side of the
vapor liquid separator to switch a refrigerant flow to allow a
liquid refrigerant passing through the vapor liquid separator to
pass through at least one of the second refrigerant circuit and the
third refrigerant circuit, includes cooling a first and a second
cooling compartment by controlling the flow path switching device
so that a refrigerant may flow through the first refrigerant
circuit and the second refrigerant circuit; and cooling the second
cooling compartment by controlling the flow path switching device
so that a refrigerant may flow through the first refrigerant
circuit and the third refrigerant circuit when a temperature of the
first cooling compartment reaches a target temperature.
[0027] The amount of a refrigerant flow in the entire cooling mode
and the freezing mode may be adjusted by controlling the number of
rotation of the compressor when an operation through the first
refrigerant circuit and the second refrigerant circuit is referred
to as an entire cooling mode, and an operation through the first
refrigerant circuit and the third refrigerant circuit is referred
to as a freezing mode.
[0028] The first evaporator may be defrosted by supplying the
compressed refrigerant discharged from the compressor to the second
refrigerant circuit since the third refrigerant circuit may be
closed and the second refrigerant circuit may be opened by
controlling the flow path switching device when driving the
compressor is stopped.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] These and/or other aspects of the disclosure will become
apparent and more readily appreciated from the following
description of embodiments, taken in conjunction with the
accompanying drawings of which:
[0030] FIG. 1 is a view of a cooling apparatus according to a first
embodiment of the present disclosure;
[0031] FIG. 2 is a view of a refrigerant flow in an ejector in the
cooling apparatus according to a first embodiment of the present
disclosure;
[0032] FIG. 3 is a Mollier diagram of the cooling apparatus
according to a first embodiment of the present disclosure;
[0033] FIG. 4 is a view of operations of each component in each
mode of the cooling apparatus according to a first embodiment of
the present disclosure;
[0034] FIG. 5 is a view of a control diagram of the cooling
apparatus according to a first embodiment of the present
disclosure;
[0035] FIG. 6A is a view of a multi cycle type cooling apparatus,
and FIG. 6B is a table comparing the multi cycle type cooling
apparatus with the cooling apparatus according to a first
embodiment of the present disclosure;
[0036] FIG. 7 is a view of a cooling apparatus according to a
second embodiment of the present disclosure;
[0037] FIG. 8 is a Mollier diagram of the cooling apparatus
according to a second embodiment of the present disclosure;
[0038] FIG. 9 is a view of a cooling apparatus according to a third
embodiment of the present disclosure;
[0039] FIG. 10 is a Mollier diagram of the cooling apparatus
according to a third embodiment of the present disclosure;
[0040] FIG. 11 is a schematic view of a refrigerator provided with
a cooling apparatus according to a fourth embodiment of the present
disclosure; and
[0041] FIG. 12 is a view of the cooling apparatus according to a
fourth embodiment of the present disclosure.
DETAILED DESCRIPTION
[0042] Reference will now be made in detail to embodiments of the
present disclosure, examples of which are illustrated in the
accompanying drawings, wherein like reference numerals refer to
like elements throughout.
[0043] FIG. 1 is a view of a cooling apparatus according to a first
embodiment of the present disclosure. FIG. 2 is a view of the
amount of refrigerant flow in an ejector in the cooling apparatus
according to a first embodiment of the present disclosure.
[0044] As illustrated in FIG. 1, a compressor 110, a condenser 120,
a first evaporator 154, a second evaporator 164, and an ejector 130
may be connected by a refrigerant pipe so that a closed loop
refrigerant circuit may be provided.
[0045] Particularly, a cooling apparatus may include a first
refrigerant circuit, a second refrigerant circuit, and a third
refrigerant circuit.
[0046] In the first refrigerant circuit, a refrigerant discharged
from the compressor 110 may flow a suction side of the compressor
110 by passing through the condenser 120, the ejector 130, and a
vapor liquid separator 140. In the second refrigerant circuit, a
refrigerant may flow the ejector 130, the vapor liquid separator
140, a first expansion device 152, a first evaporator 154, and a
second evaporator 164 and be sucked into a suction unit 132 of the
ejector 130 to be circulated. In the third refrigerant circuit, a
refrigerant passed through the vapor liquid separator 140 may flow
a second expansion device 162 and the second evaporator 164, and be
sucked into the suction unit 132 to bypass the first expansion
device 152 and the first evaporator 154.
[0047] The first refrigerant circuit may be referred to as a main
refrigerant circuit, the second refrigerant circuit may be referred
to as an entire cooling mode circuit, and the third refrigerant
circuit may be referred to as a freezing mode refrigerant
circuit.
[0048] Use of the first evaporator 154 and the second evaporator
164 are not limited thereto, but according to one embodiment of the
present disclosure, the first evaporator 154 may be used for a
refrigerating compartment 150 of a refrigerator, and the second
evaporator 164 may be used for a freezing compartment 160 of a
refrigerator. That is, the first evaporator 154 may be referred to
as a refrigerating compartment evaporator and the second evaporator
164 may be referred to as a freezing compartment evaporator.
[0049] A flow path switching device 170 may control a refrigerant
flow between the second refrigerant circuit and the third
refrigerant circuit. Particularly, the flow path switching device
170 may be installed in a discharge side of the vapor liquid
separator 140 to switch a flow path so that a liquid refrigerant
passed through the vapor liquid separator 140 may pass at least one
of the second and the third refrigerant circuit.
[0050] The flow path switching device 170 may include a three way
valve. The flow path switching device 170 may include a first valve
171 opening/closing the second refrigerant circuit and a second
valve 172 opening/closing the third refrigerant circuit.
[0051] A condenser fan motor 122 driving a condenser fan 121, a
first fan motor 158 driving a first fan 157 of the refrigerating
compartment 150, and a second fan motor 168 driving a second fan
167 of the freezing compartment 160 may be further provided.
[0052] A first defrost heater 156 and a second defrost heater 166
may be provided in the first evaporator 154 and the second
evaporator 164 to remove frost on surface of the evaporators.
[0053] An operating refrigerant flowing in the cooling apparatus
may include HCs isobutane (R600a) and propane (R290), HFCs R134a,
and HFOs R1234yf.
[0054] Expansion devices 152, 162, 280, and 390 may include a
capillary, a capillary tube and an electronic expansion valve
(EV).
[0055] The ejector 130 may include a nozzle 131, a suction unit
132, a mixing unit 133, and a diffuser 134. A refrigerant
discharged from the condenser 120 may be referred to as a main
refrigerant and refrigerant discharge from the second evaporator
164 may be referred to as a sub refrigerant. The main refrigerant
may flow to the mixing unit 133 through the nozzle 131, and the sub
refrigerant may be sucked into the suction unit 132, mixed with the
main refrigerant in the mixing unit 133 and then flow out from the
ejector 130 through the diffuser 134.
[0056] When the main refrigerant passes through the nozzle 131, the
main refrigerant may be isentropic expansion and an enthalpy
difference between the front and the back of the nozzle 131 may
cause a speed difference of the main refrigerant. Therefore, the
main refrigerant may be ejected at high speed from an outlet of the
nozzle 131.
[0057] In the diffuser 134, velocity energy of a mixed refrigerant
in which the main refrigerant and the sub refrigerant are mixed, is
converted to pressure energy, and thus there is an effect of the
boost pressure. Therefore, when suctioning, compression work may be
reduced so that an efficiency of a cycle may be increased.
[0058] Hereinafter, a refrigerant flow in the ejector 130 will be
described.
[0059] The main refrigerant discharged from the condenser 120 may
be introduced to an inlet of the nozzle 131 of the ejector 130. A
flow velocity of the main refrigerant may be increased and a
pressure may be decreased after passing through the nozzle 131 in
the ejector 130.
[0060] In an outlet of the nozzle 131, the main refrigerant may
flow in a low pressure and the sub refrigerant, which flows in a
saturated gas state due to passing through the second evaporator
164 through the second refrigerant circuit or the third refrigerant
circuit, may be sucked into the suction unit 132 of the ejector 130
due to a pressure difference with the main refrigerant having
relative lower pressure than saturation pressure.
[0061] The main refrigerant passed through the nozzle 131 and the
sub refrigerant suctioned through the suction unit 132 may be mixed
in the mixing unit 133 of the ejector 130. A flow velocity of the
mixed refrigerant may be reduced while passing through the diffuser
134 installed an outlet of the ejector 130 and having a fan shape,
and a pressure of the mixed refrigerant may be increased and
introduced to the vapor liquid separator 140.
[0062] From the vapor liquid separator 140, a vapor refrigerant may
be introduced to the suction unit of the compressor 110, and a
liquid refrigerant may pass the expansion device 152 and 162 to be
a proper temperature and pressure thereof, which is required by the
evaporator 154 and 164, and be introduced to the evaporator 154 and
164. A refrigerant in the outlet of the evaporator 154 and 164 may
become a saturated gas state since a refrigerant is evaporated by
absorbing heat from the ambient air while passing through the
evaporator 154 and 164. The refrigerant in the saturated gas state
may be sucked into the suction unit 132 of the ejector 130, as
mentioned above, and a refrigerant circulation may be
maintained.
[0063] In a cycle provided with the ejector 130, a pressure of a
refrigerant sucked into the compressor 110 may be increased
comparing with a cycle without the ejector 130, thus the amount of
work of the compressor 110 may be reduced when a refrigerant
introduced to the compressor 110 is compressed to a condensation
temperature. In addition, a liquid refrigerant passed through the
vapor liquid separator 140 may flow in the evaporator 154 and 164
provided on the second refrigerant circuit or the third refrigerant
circuit so that a cooling capacity may be improved and Coefficient
of Performance (COP) of an entire cycle may be increased.
[0064] FIG. 3 is a Mollier diagram of the cooling apparatus
according to a first embodiment of the present disclosure.
[0065] The compressor 110 may suction a low temperature and low
pressure refrigerant from the vapor liquid separator 140 and
compress low temperature and low pressure refrigerant with
superheated steam having high temperature and high pressure
(7.fwdarw.1). The superheated refrigerant with a high temperature
and a high pressure by the compressor 100 may become a liquid
refrigerant while passing through the condenser 120 to exchange
heat with the ambient air (1.fwdarw.2).
[0066] When a refrigerant condensed in the condenser 120 is
referred to as a main refrigerant, the main refrigerant may be
introduced to the nozzle 131 of the ejector 130. While a pressure
of the refrigerant introduced to the nozzle 131 is reduced, a state
of the refrigerant may be changed, that is a second state, and thus
the refrigerant in the outlet of the nozzle 131 may have a high
speed and a low pressure (2.fwdarw.3).
[0067] A suction flow path part having a shape of a concentric
circle disposed on the same cross section with the outlet of the
nozzle 131 may have a low pressure. Particularly, when a
refrigerant passed through only the second evaporator 164 or both
of the first evaporator 154 and the second evaporator 164 according
to driving modes, is referred to as a sub refrigerant, the sub
refrigerant may be introduced through the suction unit 132 of the
ejector 130. The pressure of the main refrigerant in the outlet of
the nozzle 131 may be lower than that of the sub refrigerant passed
through the evaporator 154 and 164 so that the sub refrigerant may
be sucked through the suction unit 132 of the ejector 130.
[0068] In the mixing unit 133, the main refrigerant passed through
the nozzle and the sub refrigerant passed through the evaporator
154 and 164 may be mixed so that momentum may be transferred
(3.fwdarw.4, 3'.fwdarw.4), and the mixed refrigerant may be
introduced to the diffuser 134 through the mixing unit 133
(4.fwdarw.5). In the diffuser 134, a flow velocity of the
refrigerant may be reduced and a pressure of the refrigerant may be
increased. Accordingly, while the refrigerant having increased
pressure, a vapor refrigerant among the refrigerant having
increased pressure may be introduced to the compressor 110
(5.fwdarw.7), and work of compression of the compressor 110 may be
reduced as much as increased pressure by the ejector 130 thereby
saving electricity.
[0069] The refrigerant passed through the ejector 130 may be
introduced to the vapor liquid separator 140 and may be separated
into a vapor refrigerant and a liquid refrigerant. As mentioned
above, the vapor refrigerant from the vapor liquid separator 140
may be introduced to the suction unit of the compressor 110
(5.fwdarw.7), and the liquid refrigerant may be introduced to the
flow path switching device 170 (5.fwdarw.8). In an outlet of the
flow path switching device 170, the expansion device 152 and 162
may be provided to generate a certain temperature, which is
required by the first evaporator 154 and the second evaporator 164,
and a the refrigerant may have a pressure drop while passing
through the expansion device 152 and 162.
[0070] In the entire cooling mode, the first valve 171 is opened,
and the second valve 172 is closed. The liquid refrigerant
discharged from the vapor liquid separator 140 may have a pressure
drop while passing through the first expansion device 152
(8.fwdarw.9).
[0071] The refrigerant having a pressure drop may be circulated
along the second refrigerant circuit to pass through the first
evaporator 154 and the second evaporator 165
(9.fwdarw.10.fwdarw.6). The refrigerant passing through the second
evaporator 164 may be sucked through the suction unit 132 of the
ejector 130 and during suctioning a pressure of the refrigerant may
be decreased by the main refrigerant introduced through the nozzle
131 (6.fwdarw.3').
[0072] In the freezing mode, the first valve 171 may be closed, and
the second valve 172 may be opened. The liquid refrigerant
discharged from the vapor liquid separator 140 may have a pressure
drop while passing through the second expansion device 162
(8.fwdarw.11).
[0073] The refrigerant having decreased pressure may be circulated
along the third refrigerant circuit to bypass the first evaporator
154 and to pass through the second evaporator 164 (11.fwdarw.6').
The refrigerant passing through the second evaporator 164 may be
sucked through the suction unit 132 of the ejector 130 and during
suctioning a pressure of the refrigerant may be decreased by the
main refrigerant introduced through the nozzle 131
(6'.fwdarw.3').
[0074] The flow path switching device 170 may be provided to switch
a refrigerant flow between the second refrigerant circuit and the
third refrigerant circuit according to temperature.
[0075] Only the liquid refrigerant from the vapor liquid separator
140 may pass through the expansion device 152 and 162 to flow in
the evaporator 154 and 164 so that a cooling capacity may be
increased, thereby improving the efficiency of the entire
cycle.
[0076] FIG. 4 is a view of operations of each component in each
mode of the cooling apparatus according to a first embodiment of
the present disclosure.
[0077] Pressure change of the refrigerant and changes in an
evaporation temperature in the each evaporator according to the
pressure change when the entire cooling mode and the freezing mode
of a refrigerator according to an embodiment of the present
disclosure are as follows.
[0078] In the entire cooling mode, when the first valve 171 of the
flow path switching device 170 is opened, that is the second valve
172 is closed, a refrigerant discharged from the condenser 120 may
be firstly evaporated in the first evaporator 162 after firstly
decompressing in the first expansion device 152. The refrigerant
firstly evaporated in the first evaporator 154 may be secondly
evaporated in the second evaporator 164. A freezing compartment 150
fan and a refrigerating compartment 150 fan may be driven at the
same time.
[0079] A proper temperature of a general freezing compartment may
be approximately -18.degree. C., and a proper temperature of a
general refrigerating compartment may be approximately 3.degree. C.
As mentioned above, a difference between the proper temperature for
the refrigerating compartment and the proper temperature for the
freezing compartment may be large. Therefore, when increasing the
evaporation temperature of the each evaporator to prevent the
refrigerating compartment from being excessively cooling, the
freezing compartment 160 may be not sufficiently cooled. In the
cooling apparatus according to one embodiment of the present
disclosure, when cooling in the freezing compartment 160 is not
enough, the freezing compartment 160 except the refrigerating
compartment 150 may be cooled according to a low evaporation
temperature so that a temperature in the freezing compartment 160
may quickly reach a target temperature.
[0080] When a target temperature inside the refrigerating
compartment 150 is obtained, the entire cooling mode is switched to
the freezing mode.
[0081] In the freezing mode for cooling only the freezing
compartment 160, the second valve 172 of the flow path switching
device 170 is opened, that is the first valve 171 is closed, so
that the refrigerant discharged from the condenser 120 may flow to
the second evaporator 164 through the second expansion device 162.
In the freezing mode, after being decompressed to have a lower
pressure in the second expansion device 162, the refrigerant may be
evaporated in the second evaporator 164. Due to the decompression
of the refrigerant by the second expansion 162, the evaporation
temperature of the second evaporator 164 may be lower than that of
the first evaporator 154. At this time, only the freezing
compartment 160 fan may be driven.
[0082] When the entire cooling mode is switched to the freezing
mode, the amount of a refrigerant flow flowing in the refrigerant
circuit may be reduced. Particularly, the compressor 110 may
include an inverter compressor 110 and, the amount of refrigerant
flow flowing in the refrigerant circuit may be reduced by
controlling the number of rotation of the compressor.
[0083] When the target temperature of the freezing compartment is
obtained, the compressor 110 and the second fan 167 may be stopped.
After this time, the first fan 157 may be operated during a certain
time t1, the first valve 171 may be opened, the second valve 172
may be closed, and 3.degree. C. air inside the refrigerating
compartment 150 may be circulated so that frost on the first
evaporator 154 may be defrosted. Moisture generated during the
defrosting may secure a high level of about 75% humidity inside the
refrigerating compartment 150 to significantly contribute to
keeping vegetables fresh.
[0084] FIG. 5 is a view of a control diagram of the cooling
apparatus according to a first embodiment of the present
disclosure.
[0085] A refrigerator according to one embodiment of the present
disclosure may provide various cooling modes by controlling a
control unit 60, such as MICOM (Microcomputer). FIG. 5 is a control
diagram by the control unit 60 provided on the refrigerator
according to one embodiment of the present disclosure. As
illustrated in FIG. 5, a key input unit 52, a refrigerating
compartment temperature detecting unit 54, a freezing compartment
temperature detecting unit 56, and a first evaporator temperature
detecting unit 58 may be connected to an input port of the control
unit 60. On the key input unit 52, various function keys may be
provided and the various function keys may be related to setting
driving conditions of the refrigerator, such as setting
refrigerating modes and setting target temperatures. The
refrigerating compartment temperature detecting unit 54 and the
freezing compartment temperature detecting unit 56 may detect
temperatures inside the refrigerating compartment 150 and the
freezing compartment 160, respectively to provide the temperatures
to the control unit 60. The first evaporator temperature detecting
unit 58 may detect an evaporation temperature of the refrigerant in
the first evaporator 154 to provide to the control unit 60.
[0086] A compressor driving unit 62, a first fan driving unit 64, a
second fan driving unit 66, a flow path switching device driving
unit 68, a display unit 70, and a defrost heater driving unit 72
may be connected to an output port of the control unit 60. The
driving units except for the display unit 70 may drive the
compressor 110, the refrigerating compartment fan motor 158, the
freezing compartment fan motor 168, the first valve 171 and the
second valve 172 of the flow path switching device 170, and the
defrost heater 156 and 166, respectively. The display unit 70 may
display an operation state of the cooling apparatus, various
setting values, temperatures, etc.
[0087] The control unit 60 may control the flow path switching
device 170 to allow a refrigerant to be circulated on at least one
of the second refrigerant circuit and the third refrigerant
circuit, as illustrated in FIG. 5, so that various cooling modes
may be realized. A representative cooling mode in the refrigerator
according to one embodiment of the present disclosure may be a
first cooling mode, that is an entire cooling mode, and a second
cooling mode, that is a freezing mode. The entire cooling mode may
be defined as an operation mode cooling both the refrigerating
compartment 150 and the freezing compartment 160. The control unit
60 may open the first valve 171 of the flow path switching device
170 to realize the entire cooling mode. In the entire cooling mode,
a refrigerant discharge from the condenser 120 may be circulated
through the first expansion device 152, the first evaporator 154
and the second evaporator 164.
[0088] The freezing mode may be defined as an operation mode
cooling only the freezing compartment 160. The control unit 60 may
open the second valve 172 of the flow path switching device 170 to
realize the freezing mode. In the freezing mode, a refrigerant
discharge from the condenser 120 may be circulated through the
second expansion device 162, and the second evaporator 164.
[0089] By this configuration, as mentioned above, when cooling the
refrigerating compartment 150 and the freezing compartment 160
through the first evaporator 154 and the second evaporator 164,
respectively, the refrigerator may be initially operated in a
simultaneous cooling mode, and when reaching a predetermined
temperature, the simultaneous cooling mode may be switched to a
cooling mode cooling only the freezing compartment 160, thereby
maximizing cooling capacity. In addition, the refrigerant having
increased pressure by the ejector 130 may be sucked into the
compressor 110 so that work of compression may be reduced. The
entire cooling mode may allow a refrigerant passed through the
first evaporator 154 to pass through the second evaporator 164, so
that a liquid refrigerant, which is not evaporated in the first
evaporator 154, may be evaporated in the second evaporator 164, and
thus a refrigerant sufficiently evaporated may be sucked into the
suction unit 132 of the ejector 130. Therefore, the suction
operation of the ejector 130 may be smooth, and thereby a stable
operation may be obtained. Further, the amount of refrigerant flow
using in the entire cooling mode may be less than the amount of
refrigerant flow using in the freezing mode, and a difference may
be controlled by the number of a rotation of the inverter
compressor 110 so that efficient operation may be obtained.
[0090] FIG. 6A is a view of a multi cycle type cooling apparatus,
and FIG. 6B is a table comparing the multi cycle type cooling
apparatus with the cooling apparatus according to a first
embodiment of the present disclosure.
[0091] FIG. 6A is a view illustrating a multi cycle type cooling
apparatus (A) not having the ejector 130 and the vapor liquid
separator 140, and FIG. 6B is a table of comparing coefficient of
performance of the multi cycle type cooling apparatus (A) with the
cooling apparatus (B) according to one embodiment of the present
disclosure.
[0092] The multi cycle type cooling apparatus (A) may include a
first refrigerant circuit and a second refrigerant circuit and a
flow path switching device 170a. In the first refrigerant circuit,
a refrigerant discharged from a compressor 110a may flow to a
suction side of the compressor 110a through a condenser 120a, a
first expansion device 152a, a first evaporator 154a and a second
evaporator 164a. In the second circuit, a refrigerant passed
through the condenser 120a may flow to a suction side of the
compressor 110a through a second expansion device 162a and a second
evaporator 164a, and then bypass the first evaporator 154a and the
first expansion device 152a. The flow path switching device 170a
may switch a flow path so that the refrigerant may flow through at
least one of the first refrigerant circuit and the second
refrigerant circuit.
[0093] In FIG. 6B, QR represents a freezing capacity in the
refrigerating compartment 150, QF represents a freezing capacity in
the freezing compartment 160, m represents a flow, Q1 represents a
freezing capacity in the entire cooling mode, W1 represents the
amount of work of the compressor 110 in the entire cooling mode, Q2
represents freezing capacity in the freezing mode, and W2
represents the amount of work of the compressor 110 in the entire
cooling mode.
[0094] Coefficient of Performance (COP) may be a value obtained by
dividing a total freezing capacity (Qt) of the combined Q1 and Q2
with the total amount of work (Wt) of the compressor of the
combined W1 and W2. To compare COP of the multi cycle type cooling
apparatus (A) with COP of the cooling apparatus (B) according to
one embodiment of the present disclosure, when COP of the multi
cycle type cooling apparatus (A) is assumed as 1, COP.sub.--1 may
represent COP of the cooling apparatus (B) according to one
embodiment of the present disclosure.
[0095] As illustrated in the table shown in FIG. 6B, each cooling
capacity in the entire cooling mode and the freezing mode may set
to be the same value to compare the performance of the cycle.
[0096] In comparison with the multi cycle type cooling apparatus
(A), the cooling apparatus (B) may have a larger the amount of
refrigerant flow since a vapor refrigerant and a liquid refrigerant
may be independently circulated using by the vapor liquid separator
140. In addition, in comparison with the entire cooling mode, in
the freezing mode, the first evaporator 154 may be bypassed so that
the amount of refrigerant flow may be less.
[0097] Accordingly, in comparison with the multi cycle type cooling
apparatus (A), COP of the cooling apparatus (B) according to one
embodiment may be improved by 1.2 times. That is, the vapor liquid
separator 140 may allow the liquid refrigerant to sufficiently flow
in the evaporator so that a cooling capacity may be improved and in
comparison with the multi cycle type cooling apparatus (A) being
not provided with the ejector 130, the cooling apparatus may
provided with the ejector 130 to increase pressure of suctioned
refrigerant to the compressor 110 so that the amount of work of
compression of the compressor 110 may be reduced.
[0098] FIG. 7 is a view of a cooling apparatus according to a
second embodiment of the present disclosure, and FIG. 8 is a
Mollier diagram of the cooling apparatus according to a second
embodiment of the present disclosure.
[0099] Hereinafter, a cooling apparatus according to a second
embodiment of the present disclosure will be described.
[0100] A description of the same parts as those described above
will be omitted. For example, the diffuser 134 shown in the first
embodiment is shown as the diffuser 234 in the second
embodiment.
[0101] Particularly, a cooling apparatus may include a first
refrigerant circuit, a second refrigerant circuit, and a third
refrigerant circuit.
[0102] In the first refrigerant circuit, a refrigerant discharged
from a compressor 210 may flow to a suction side of the compressor
210 through a condenser 220, an ejector 230, and a vapor liquid
separator 240. In the second refrigerant circuit, a refrigerant may
be sucked into an inlet of the ejector 230 to be circulated by
passing through the ejector 230, the vapor liquid separator 240, a
first expansion device 252, a first evaporator 254 and a second
evaporator 264. In the third refrigerant circuit, the refrigerant
passing through the vapor liquid separator 240 may be sucked into
an inlet of the ejector 230 by passing through a second expansion
device 262 and the second evaporator 264 to bypass the first
expansion device 252 and the first evaporator 254.
[0103] Use of the first evaporator 254 and the second evaporator
264 are not limited thereto, but according to one embodiment of the
present disclosure, the first evaporator 254 may be used in a
refrigerating compartment 250 of a refrigerator, and the second
evaporator 264 may be used in a freezing compartment 260 of a
refrigerator. That is, the first evaporator 254 may be referred to
as a refrigerating compartment evaporator and the second evaporator
264 may be referred to as a freezing compartment evaporator.
[0104] A flow path switching device 270 may control the amount of
refrigerant flow between the second refrigerant circuit and the
third refrigerant circuit. Particularly, the flow path switching
device 270 may be installed in a discharge side of the vapor liquid
separator 240 to switch a flow path so that a liquid refrigerant
passed through the vapor liquid separator 240 may pass at least one
of the second and the third refrigerant circuit.
[0105] The flow path switching device 270 may include a three way
valve. The flow path switching device 270 may include a first valve
271 opening/closing the second refrigerant circuit and a second
valve 272 opening/closing the third refrigerant circuit.
[0106] A condenser fan motor 222 driving a condenser fan 221, a
first fan motor 258 driving a first fan 257 of the refrigerating
compartment 250, and a second fan motor 268 driving a second fan
267 of the freezing compartment 260 may be further provided.
[0107] A first defrost heater 256 and a second defrost heater 266
may be provided in the first evaporator 254 and the second
evaporator 264 to remove frost on surface of the evaporators.
[0108] The first refrigerant circuit may include heat exchangers
270 and 272.
[0109] The heat exchanger 270 and 272 may be provided to exchange
heat between a discharge unit of the condenser 220 and an inlet of
the compressor 210. It is desirable that a liquid refrigerant may
be introduced to the compressor 210, but a vapor refrigerant may be
introduced. Thus, for the prevention of damage or the performance
degradation of the compressor 210, the heat exchangers 270 and 272
may be provided to exchange heat between an outlet of the condenser
220 and the inlet of the compressor 210.
[0110] The heat exchangers 270 and 272 may include a first heat
exchanger 270 provided on the discharge unit of the condenser 220
and a second heat exchanger 272 provided on the inlet of the
compressor 210. By transferring heat from the first heat exchanger
270 to the second heat exchanger 272 (2'' in FIG. 2), a liquid
refrigerant may be overheated to be a vapor refrigerant. (7'' in
FIG. 8)
[0111] The first refrigerant circuit may include a third expansion
device 280.
[0112] The third expansion device 280 may be installed between the
condenser 220 and the ejector 230. When a refrigerant introduced to
a nozzle 231 of the ejector 230 is in a two phase state, an
efficiency of the ejector 230 may be improved. Therefore, the third
expansion device 280 may be provided so that a humidity of a
refrigerant discharged from the condenser 220 may be increased.
[0113] The third expansion device 280 the heat exchangers 270 and
272 may be provided at the same time. The heat exchangers 270 and
272 may include a Suction Line heat exchanger (SLHX) provided
between the third expansion device 280 and the suction unit of the
compressor 210. Superheat of a refrigerant introduced to the
compressor 210 may be obtained by the Suction Line heat exchanger
(SLHX) so that a damage to the compressor 210 caused by introducing
a liquid refrigerant may be prevented and an efficiency of the
ejector may be improved by the third expansion device 230.
[0114] It may be desirable that the amount of pressure drop by the
third expansion device 280 is within 30% of the amount of pressure
drop by the nozzle 231 of the ejector 230.
[0115] FIG. 9 is a view of a cooling apparatus according to a third
embodiment of the present disclosure, and FIG. 10 is a Mollier
diagram of the cooling apparatus according to a third embodiment of
the present disclosure.
[0116] Hereinafter, a cooling apparatus according to a third
embodiment of the present disclosure will be described.
[0117] A description of the same parts as those described above
will be omitted. For example, the diffuser 134 shown in the first
embodiment is shown as the diffuser 334 in the third
embodiment.
[0118] Particularly, a cooling apparatus may include a first
refrigerant circuit, a second refrigerant circuit, and a third
refrigerant circuit.
[0119] In the first refrigerant circuit, a refrigerant discharged
from a compressor 310 may flow to a suction side of the compressor
310 through a condenser 320, an ejector 330, and a vapor liquid
separator 340. In the second refrigerant circuit, a refrigerant may
be sucked into an inlet of the ejector 330 to be circulated by
passing through the ejector 330, the vapor liquid separator 340, a
first expansion device 352, a first evaporator 354 and a second
evaporator 364. In the third refrigerant circuit, the refrigerant
passing through the vapor liquid separator 340 may be sucked into
an inlet of the ejector 330 by passing through a second expansion
device 362 and the second evaporator 364 to bypass the first
expansion device 352 and the first evaporator 354.
[0120] Use of the first evaporator 354 and the second evaporator
364 are not limited thereto, but according to one embodiment of the
present disclosure, the first evaporator 354 may be used in a
refrigerating compartment 350 of a refrigerator, and the second
evaporator 364 may be used in a freezing compartment 360 of a
refrigerator. That is, the first evaporator 354 may be referred to
as a refrigerating compartment evaporator and the second evaporator
364 may be referred to as a freezing compartment evaporator.
[0121] A flow path switching device 370 may control the amount of
refrigerant flow between the second refrigerant circuit and the
third refrigerant circuit. Particularly, the flow path switching
device 370 may be installed in a discharge side of the vapor liquid
separator 340 to switch a flow path so that liquid refrigerant
passed through the vapor liquid separator 340 may pass at least one
of the second and the third refrigerant circuit.
[0122] The flow path switching device 370 may include a three way
valve. The flow path switching device 370 may include a first valve
371 opening/closing the second refrigerant circuit and a second
valve 372 opening/closing the third refrigerant circuit.
[0123] A condenser fan motor 322 driving a condenser fan 321, a
first fan motor 358 driving a first fan 357 of the refrigerating
compartment 350, and a second fan motor 368 driving a second fan
367 of the freezing compartment 360 may be further provided.
[0124] A first defrost heater 356 and a second defrost heater 366
may be provided in the first evaporator 354 and the second
evaporator 364 to remove frost on surface of the evaporators.
[0125] When two evaporators connected by a refrigerant pipe having
the same internal diameter as a refrigerant pipe provided in a
suction side of the compressor 310, in the entire cooling mode,
each evaporation temperature of the first evaporator 354 and the
second evaporator 364 may be the same. In this case, when
considering cooling the freezing compartment 360 and decreasing the
evaporation temperature of the second evaporator 364, a surface of
the first evaporator 354 may be frosted up, and when increasing the
evaporation temperature of the second evaporator 364 to prevent
frost, sufficient cooling of the freezing compartment 360 may not
be obtained.
[0126] Those difficulties may be solved by connecting the second
evaporator 364 and the first evaporator 354 to an intermediate
expansion device 390.
[0127] The first expansion device 352 may decrease a pressure of a
refrigerant passing through the condenser 320 so that a refrigerant
may be evaporated at an evaporation temperature required by the
first evaporator 354. The intermediate expansion device 390 may
decrease a pressure of the refrigerant passing through the first
evaporator 354 once again so that the refrigerant may be evaporated
at an evaporation temperature required by the second evaporator
364. (12 in FIG. 10) That is because the evaporation temperature
required by the second evaporator 364 may be lower than the
evaporation temperature required by the first evaporator 354. The
second expansion device 362 may decompress the refrigerant passing
through the condenser 320 so that the refrigerant may be evaporated
at an evaporation temperature required by the second evaporator
364. That is the second expansion device 362 may directly
decompress the refrigerant passing through the condenser 320 until
the refrigerant may be evaporated at the evaporation temperature
required by the second evaporator 364, whereas the intermediate
expansion device 390 may decrease a pressure of the refrigerant,
which is firstly decompressed by the first expansion device 352,
once again. In this regard, a resistance of the second expansion
device 362 may be larger than that of the intermediate expansion
device 390 and accordingly a level of the decompression in the
second expansion device 362 and the intermediate expansion device
390 may allow the evaporation temperature required by the second
evaporator 364 to be realized. In addition, an internal diameter of
the intermediate expansion device 390 may be smaller than that of
the refrigerant pipe disposed on the suction side of the compressor
310, e.g. approximately 2.about.4 mm, so that the refrigerant may
be compressed while passing through the intermediate expansion
device 390. When the internal diameter of the intermediate
expansion device 390 may be extremely large, an evaporation
temperature difference between two evaporators may be not
significant, and when the internal diameter of the intermediate
expansion device 390 is extremely small, an excessively large
resistance may be generated in a refrigerant flow in which a liquid
refrigerant and a vapor refrigerant are mixed in the first
evaporator 354 and thereby a cooling speed of the refrigerating
compartment 350 may be slow.
[0128] FIG. 11 is a schematic view of a refrigerator provided with
a cooling apparatus according to a fourth embodiment of the present
disclosure and FIG. 12 is a view of the cooling apparatus according
to a fourth embodiment of the present disclosure.
[0129] Hereinafter, a cooling apparatus according to a fourth
embodiment of the present disclosure will be described.
[0130] A description of the same parts as those described above
will be omitted. For example, the diffuser 134 shown in the first
embodiment is shown as the diffuser 434 in the fourth
embodiment.
[0131] A refrigerator may include a refrigerating compartment 401,
a freezing compartment 402, and a converting compartment 403. Those
sections may be configured to have three independent temperature
zones.
[0132] The refrigerator may be driven by a dual loop cycle. The
dual loop cycle may include a first cooling apparatus 404 and a
second cooling apparatus 400.
[0133] The first cooling apparatus 404 and the second cooling
apparatus 400 may be independently operated without interfering
with each other.
[0134] The first cooling apparatus 404 may be provided to lower a
temperature inside the refrigerating compartment 401 to a target
temperature.
[0135] The first cooling apparatus 404 may include a compressor
405, a condenser 406, an expansion device 407, and an evaporator
408. A refrigerant compressed by the compressor 405 may be
discharged in a liquid state having a high temperature and a high
pressure while passing through the condenser 406, and may be
discharged in a vapor state having a low temperature and a low
pressure while passing through the expansion device 407 and the
evaporator 408, and then be introduced once again to the compressor
405.
[0136] The second cooling apparatus 400 may be provided to lower
temperatures inside the freezing compartment 402 and the converting
compartment 403 to a target temperature.
[0137] The second cooling apparatus 400 may include a first
refrigerant circuit, a second refrigerant circuit, and a third
refrigerant circuit.
[0138] In the first refrigerant circuit, a refrigerant discharged
from a compressor 410 may flow to a suction side of the compressor
410 through a condenser 420, an ejector 430, and a vapor liquid
separator 440. In the second refrigerant circuit, a refrigerant may
be sucked into an inlet of the ejector 430 to be circulated by
passing through the ejector 430, the vapor liquid separator 440, a
first expansion device 452, a first evaporator 454 and a second
evaporator 464. In the third refrigerant circuit, the refrigerant
passing through the vapor liquid separator 440 may be sucked into
an inlet of the ejector 430 by passing through a second expansion
device 462 and the second evaporator 464 to bypass the first
expansion device 452 and the first evaporator 454.
[0139] Use of the first evaporator 454 and the second evaporator
464 are not limited thereto, but according to one embodiment of the
present disclosure, the first evaporator 454 may be used in the
converting compartment 403 of the refrigerator, and the second
evaporator 464 may be used in the freezing compartment 460 of the
refrigerator. That is, the first evaporator 454 may be referred to
as the converting compartment evaporator and the second evaporator
464 may be referred to as a freezing compartment evaporator.
[0140] A flow path switching device 470 may control the amount of
refrigerant flow between the second refrigerant circuit and the
third refrigerant circuit. Particularly, the flow path switching
device 470 may be installed in a discharge side of the vapor liquid
separator 440 to switch a flow path so that a liquid refrigerant
passed through the vapor liquid separator 440 may pass at least one
of the second and the third refrigerant circuit.
[0141] The flow path switching device 470 may include a three way
valve. The flow path switching device 470 may include a first valve
471 opening/closing the second refrigerant circuit and a second
valve 472 opening/closing the third refrigerant circuit.
[0142] A condenser fan motor 422 driving a condenser fan 421, a
first fan motor 458 driving a first fan 457 of the converting
compartment 403, and a second fan motor 468 driving a second fan
467 of the freezing compartment 460 may be further provided.
[0143] A first defrost heater 456 and a second defrost heater 466
may be provided in the first evaporator 454 and the second
evaporator 464 to remove frost on surface of the evaporators
[0144] As is apparent from the above description, by allowing a
liquid refrigerant to sufficiently flow in the evaporator, a
cooling capacity may be improved, and the amount of work of
compression may be reduced by increasing a pressure of a suction
refrigerant of the compressor.
[0145] By changing a refrigerant flow according to modes, a cooling
efficiency and a freezing efficiency may be improved.
[0146] By improving a structure of the cooling apparatus,
Coefficient of Performance (COP) may be improved.
[0147] Although a few embodiments of the present disclosure have
been shown and described, it would be appreciated by those skilled
in the art that changes may be made in these embodiments without
departing from the principles and spirit of the disclosure, the
scope of which is defined in the claims and their equivalents.
* * * * *