U.S. patent application number 13/186700 was filed with the patent office on 2012-03-01 for modular refrigerator and icemaker.
This patent application is currently assigned to Alexander Rafalovich. Invention is credited to Alexander Rafalovich.
Application Number | 20120047917 13/186700 |
Document ID | / |
Family ID | 45695308 |
Filed Date | 2012-03-01 |
United States Patent
Application |
20120047917 |
Kind Code |
A1 |
Rafalovich; Alexander |
March 1, 2012 |
MODULAR REFRIGERATOR and ICEMAKER
Abstract
A refrigerator includes a cabinet, a sealed system, a cooling
recipient, and a heat pipe. To transport cooling capacity to the
cooling recipient, evaporator in the sealed system includes a cold
plate section with heat transfer surface. A cold end of the heat
pipe is attached to the cold plate section of the evaporator. An
internal refrigerating or freezing compartment, an external
compartment, an ice maker, or an ice-making cabinet could be a
recipient of cooling capacity. Air flowing around a warm end of the
heat pipe brings cooling potential to the internal and/or external
compartments. Icemaker and/or ice-making cabinet can be located in
the freezing compartment, in the freezing compartment door, in
refrigerating compartment, or in refrigerating compartment door. To
facilitate heat transfer the warm end of the heat pipe is in heat
transfer contact with an ice making cavity that receives and
freezes water to ice. Depending on design and application an
assembly of the cold plate section of the evaporator and the cold
end of the heat pipe can be accessible either from inside or from
outside of the refrigerator.
Inventors: |
Rafalovich; Alexander;
(Sarasota, FL) |
Assignee: |
Rafalovich; Alexander
Sarasota
FL
|
Family ID: |
45695308 |
Appl. No.: |
13/186700 |
Filed: |
July 20, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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61402287 |
Aug 27, 2010 |
|
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Current U.S.
Class: |
62/66 ; 62/186;
62/340; 62/449; 62/452; 62/455 |
Current CPC
Class: |
F25D 11/025 20130101;
F25C 5/22 20180101; F25D 23/04 20130101; F28D 15/0275 20130101;
F25B 23/006 20130101; F25B 5/00 20130101; F25C 2400/10 20130101;
F28D 2021/0071 20130101; F25B 2600/2511 20130101 |
Class at
Publication: |
62/66 ; 62/452;
62/449; 62/340; 62/455; 62/186 |
International
Class: |
F25D 11/00 20060101
F25D011/00; F25D 17/06 20060101 F25D017/06; F25C 1/00 20060101
F25C001/00; F25D 23/02 20060101 F25D023/02 |
Claims
1. A refrigerator with a refrigerator cabinet, a cooling recipient,
control means, and a refrigeration sealed system including: a
compressor to compress refrigerant vapor; a condenser to condense
vapor refrigerant to liquid; an expansion device; an evaporator
with a cold plate section to evaporate liquid refrigerant, said
cold plate section with a heat transfer surface configured to have
refrigerant flow therethrough to absorb heat and wherein liquid
refrigerant evaporates; a heat pipe with a cold end that is in heat
transfer contact with the heat transfer surface of the cold plate
and a warm end that is in heat transfer communications with the
cooling recipient providing cooling to said recipient.
2. The refrigerator according to claim 1 further comprising an
internal cooling compartment inside of the refrigerator cabinet, a
door to access to this compartment, and an evaporating section of
the evaporator to evaporate a part of liquid refrigerant providing
cooling to said cooling compartment.
3. The refrigerator according to claim 2 wherein the cooling
compartment is a freezing compartment
4. The refrigerator according to claim 2 wherein the cooling
compartment is a refrigerating compartment.
5. The refrigerator according to claim 1 wherein an assembly of the
cold plate section of the evaporator and the cold end of the heat
pipe is accessible from outside of the refrigerator cabinet.
6. The refrigerator according to claim 1 wherein an assembly of the
cold plate section of the evaporator and the cold end of the heat
pipe is accessible from inside of the refrigerator cabinet.
7. The refrigerator according to claim 1 wherein the cooling
recipient is an icemaker.
8. The refrigerator according to claim 7 wherein the warm end of
the heat pipe is disposed either in the refrigerating compartment
or in the door of the refrigerating compartment and wherein either
said compartment or said door contains the icemaker.
9. The refrigerator according to claim 8 wherein the icemaker
includes an ice making cavity for receiving water and freezing
water to ice and wherein the warm end of the heat pipe is in heat
transfer contact with the ice making cavity.
10. The refrigerator according to claim 7 wherein icemaker located
either in the freezing compartment or in the door of the freezing
compartment and wherein the warm end of the heat pipe is disposed
in said compartment or said door.
11. The refrigerator according to claim 10 wherein the icemaker
includes an ice making cavity for receiving water and freezing
water to ice and wherein the warm end of the heat pipe is in heat
transfer contact with the ice making cavity.
12. The refrigerator according to claim 1 wherein the cooling
recipient is an internal cooling compartment inside of the
refrigerator cabinet.
13. The refrigerator according to claim 12 wherein the internal
cooling compartment is a refrigerating compartment.
14. The refrigerator according to claim 1 wherein the cooling
recipient is an external cooling compartment.
15. The refrigerator according to claim 1 wherein the refrigeration
sealed system includes a multi-way valve located after the
condenser directing refrigerant flow to the evaporating
sections.
16. The refrigerator according to claim 1 having a fan to enhance
heat transfer from the warm end of the heat pipe to the cooling
recipient.
17. The refrigerator according to claim 16 wherein the cooling
recipient is provided with a temperature sensor that sends a signal
to stop the fan when the cooling recipient temperature reaches or
drops below a set temperature.
18. The refrigerator according to claim 17 wherein the cold plate
is provided with a cold plate temperature sensor that sends signals
to stop refrigerant flow through the cold plate when the cold plate
temperature drops below a predetermined temperature level or
derivative of the cold plate temperature change exceeds a
predetermined pace of the temperature reduction.
19. A method for refrigerating, freezing, and ice-making with a
refrigerator comprising of a refrigerator cabinet, a refrigeration
sealed system, a heat pipe with a cold and a warm ends, and a
recipient to be provided with cooling, said refrigeration sealed
system consisting of all essential elements of refrigeration sealed
systems including a compressor, a condenser, an expansion device,
and an evaporator that includes a cold plate section with a heat
transfer surface, said cold plate section is configured to have
refrigerant flow there through; the method to transfer cooling
potential from the evaporator to the cooling recipient by
positioning the cold end of the heat pipe in heat transfer contact
with the heat transfer surface of the cold plate and the warm end
in heat transfer communications with the cooling recipient.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to residential and commercial
refrigerators, freezers, icemakers, and other cooling
apparatuses.
[0002] Main assembly in existing refrigerators and other cooling
appliances consists of a sealed system, an insulated cabinet with
one or several doors, and a control system. Basic parts of the
sealed system include a compressor, a condenser, an expansion
device that is often a capillary tube, an evaporator, and
hermetically sealed connecting lines (tubes) delivering refrigerant
to and from compressor, condenser, and evaporator. In addition,
sealed system may be equipped with a drier, an accumulator and a
receiver. Some sealed systems may have extra evaporators, expansion
devices, compressors, condensers, and refrigerant valves. In medium
and large refrigerators sealed system includes elements to provide
airflow through condenser and evaporator.
[0003] Refrigerator may also include an icemaker whereto cooling
potential is delivered mainly by airflow while in stand alone
icemakers the cooling potential may be absorbed from evaporating
refrigerant in thermal contact with an ice making surface.
[0004] In many existing refrigerating appliances compressor,
condenser, and some auxiliary parts are located in a machine
compartment, while evaporator is either in the freezing and/or
refrigerating compartments or in the machine compartment. If
evaporator is in the machine compartment, the evaporator heat
transfer surface is in air communications with freezing and/or
cooling compartments.
[0005] This arrangement doesn't allow any meaningful variation in
the refrigerator compartments without redesigning of the sealed
system. It's hard to add a compartment, an icemaker, or to increase
or reduce width and height of an existing compartment without
considerable changes in the sealed system including redesign of
airflow passages, evaporators, fans, and so on.
[0006] Another problem with existing refrigerators is diagnostics
and repair. It's almost impossible to find a refrigerant leak in
the sealed system, if the leak is in foamed connection tubes. It
may also be very expensive to fix any dent in the walls or local
damage of the compartment liner. Thus, often it's cheaper to trash
a whole refrigerator than to repair it.
[0007] While designing a new refrigerator it's also complicated to
position an icemaker in the cooling compartment. For example, to
put an icemaker in the fresh food (refrigerating) compartment or to
make an additional compartment for an icemaker in the door of this
compartment, special air passages from the freezing compartment
or/and an additional evaporator are needed.
[0008] All these problems could be solved if it was a way to
transfer cooling capacity from the evaporator to different parts of
the refrigerator without special air passages.
[0009] One way to eliminate a need in complicated air system is
implementing a heat pipe as means for delivering cooling capacity
to any point of refrigerator. U.S. Pat. No. 4,003,214 considers
location of the icemaker in the refrigerating compartment with a
heat pipe transferring cooling capacity from the freezer to the
icemaker. According to this patent the cold end of the heat pipe is
located in a freezing compartment and a warm end is in a water
reservoir of the ice-making system transferring cooling potential
to freezing water. However, U.S. Pat. No. 4,003,214 considers heat
pipe as a means to deliver cooling potential only to the icemaker.
Besides, there are a couple weaknesses in this design. One is in
transferring of cooling potential from the freezing compartment to
the cold end of the heat pipe by natural air convection. Even with
well-developed fins on the cold end of the heat pipe heat transfer
by natural convection considerably increases heat pipe temperature
that, in turn, reduces efficiency. Adding a fan to assist in heat
transfer from the freezer or the freezer evaporator to the heat
pipe cold end requires extra room and energy for the fan and only
partly improves efficiency. Another weakness of U.S. Pat. No.
4,003,214 is in positioning the warm end of the heat pipe in a
reservoir filled with water to be frozen. It considerably
complicates ice harvesting from the icemaker.
SUMMARY OF THE INVENTION
[0010] One preferred embodiment of the invention provides a
refrigerator comprising a refrigerator cabinet, a cooling
recipient, control means, and a refrigeration sealed system
including: a compressor, a condenser, an expansion device, an
evaporator with a cold plate section with a heat transfer surface
configured to have refrigerant flow therethrough to absorb heat and
wherein at least a part of liquid refrigerant evaporates, a heat
pipe, wherein a cold end of the heat pipe is in heat transfer
contact with the cold plate while a warm end of the heat pipe is in
heat transfer communications with the cooling recipient providing
cooling to said recipient.
[0011] Another preferred embodiment of the invention provides a
refrigerator further comprising an internal cooling compartment
inside of the refrigerator cabinet, a door to access to this
compartment, and an evaporating section of the evaporator to
evaporate a part of liquid refrigerant providing cooling to the
cooling compartment.
[0012] Another embodiment of the invention further provides the
internal cooling compartment operating as a freezing
compartment.
[0013] Yet another embodiment of the invention provides the
internal cooling compartment operating as a refrigerating
compartment.
[0014] Another preferred embodiment of the invention provides a
refrigerator wherein the cold end of the heat pipe is attached to
the heat transfer surface of the cold plate and an assembly of the
cold plate section of the evaporator and the cold end of the heat
pipe is accessible from outside of the refrigerator.
[0015] Yet another embodiment of the invention provides a
refrigerator wherein the cold end of the heat pipe is attached to
the heat transfer surface of the cold plate and an assembly of the
cold plate section of the evaporator and the cold end of the heat
pipe is accessible from inside of the refrigerator.
[0016] Another preferred embodiment provides a refrigerator
comprising an icemaker as a cooling recipient.
[0017] Further in accordance with the present invention the
icemaker and the warm end of the heat pipe is disposed either in
the freezing or in the refrigerating compartment.
[0018] Yet another embodiment provides a refrigerator with the
icemaker and the warm end of the heat pipe disposed either in the
freezing or in the refrigerating compartment door. Further in
accordance with the present invention the icemaker includes a body
with an ice making cavity for receiving water and freezing water to
ice and wherein the warm end of the heat pipe is in heat transfer
contact with surface of the cavity.
[0019] In accordance with another aspect of the invention the
cooling recipient is an internal cooling compartment inside of the
refrigerator cabinet.
[0020] Further in accordance with the present invention the
internal cooling compartment that is the cooling recipient is a
refrigerating compartment.
[0021] Still another preferred embodiment of the invention provides
a refrigerator with an external cooling compartment.
[0022] Yet another embodiment of the invention provides a
refrigerator with a refrigeration sealed system that includes a
multi-way valve located after the condenser directing refrigerant
flow to the evaporating sections.
[0023] Yet another embodiment of the invention provides a
refrigerator with an air fan to enhance heat transfer from the warm
end of the heat pipe to the cooling recipient. Still another
embodiment of the invention provides a refrigerator wherein the
cooling recipient is equipped with a temperature sensor that sends
a signal to stop the fan when the cooling recipient temperature
reaches or drops below a set temperature.
[0024] Still another preferred embodiment of the invention provides
a refrigerator with a cold plate temperature sensor that sends a
signal to stop refrigerant flow through the cold plate when the
cold plate temperature drops below predetermined temperature level
or derivative of the cold plate temperature drop exceeds a
predetermined level.
[0025] Another preferred embodiment of the invention provides a
method for refrigerating, freezing, and ice-making with a
refrigerator comprising of a refrigerator cabinet, a refrigeration
sealed system, a heat pipe, and a recipient to be provided with
cooling; said sealed system consists of all essential elements of
compression-refrigeration sealed system and a cold plate section
configured to have a refrigerant flow therethrough to absorb heat
and wherein at least a part of liquid refrigerant evaporates, said
cold plate is with a heat transfer surface; the method to transfer
cooling potential from the evaporator to the cooling capacity
recipient by attaching one end of the heat pipe to the heat
transfer surface of the cold plate while another end is in heat
transfer communications with the cooling recipient.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is sealed system schematics.
[0027] FIG. 2 is a heat pipe.
[0028] FIG. 3 is schematics of modular refrigerator with sealed
system of FIG. 1.
[0029] FIG. 4 is a refrigerator with icemaker in a compartment
door.
[0030] FIG. 5 is a refrigerator with icemaker inside of
refrigerating compartment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0031] FIG. 1 shows sealed system schematics of a refrigerator with
a heat pipe. Compressed gaseous refrigerant after compressor 1
flows to condenser 3 wherein high-pressure refrigerant cools down
and condenses rejecting heat to airflow driven by fan 5. Liquid
refrigerant through dryer 7 flows to multi-way valve 9. The valve
depicted in FIG. 1 is a 3-way valve. However, it may be 2, 4, 5,
N-way valve, or may be no valve at all. The 3-way step motor valve
of Sanyo can be used as the 3-way valve depicted in FIG. 1. After
valve 9 liquid refrigerant flows to expansion devices 11 and 13
that, for example, may be capillary tubes, and further to an
evaporator that consists from several sections including cold plate
sections 15, 17, and a conventional evaporating section 19. Cold
plates 15, 17 are configured to have refrigerant flow therethrough
to absorb heat and wherein at least a part of liquid refrigerant
evaporates. Each cold plate section has a surface that is in heat
transfer relations with cold end 25 or 27 of heat pipes 21, 23.
Conductive surface of the heat pipe cold end is attached either
straight to the cold plate or through intermediate conductive
media. The surfaces of the cold plate and the cold end of the heat
pipe may be flat or rounded or any other shape providing good
thermal contact between the cold plate and the cold end. The second
(warm) end of heat pipes 21, 23 extends to a refrigerator
compartment and/or another cooling capacity recipient. A cooling
capacity recipient could be a fresh food compartment, a kimchi
compartment, an icemaker, or any other apparatus that requires and
receives cooling potential. After evaporator sections vapor
refrigerant flows through suction line 12 back to compressor 1. To
increase efficiency and capacity one or both cap tubes 11, 13 may
be attached to suction line 12. In depicted in FIG. 1 sealed system
refrigerant flows through cold plate sections 15 and 19 in
parallel, while to get to section 19 refrigerant first flows
through section 15. However, it could be a different arrangement
for refrigerant flow. For example, cold plate sections 15 and 17
may be in serious connections. 3-way valve 9 may have several
positions. One allows refrigerant to flow only through capillary
tube 11 to the cold plate section 15 and to the evaporating section
19. Another valve position allows refrigerant to flow to capillary
tube 13 and to the section 17. Yet third valve position directs
refrigerant to both cap tubes 11 and 13 to reach all sections 15,
17, 19. Valve 9 may also be closed preventing refrigerant flow to
any evaporating section.
[0032] As it is shown in FIG. 1 there are heat pipes 21, 23 with
cold ends 25, 27 attached to heat transfer surfaces of cold plate
sections 15, 17 respectively. Connections and contact area of the
cold end of each heat pipe and cold plate sections of the
evaporator are designed a way that provides efficient heat transfer
from evaporating in the cold plate refrigerant to condensing in the
cold end heat pipe media. Another (warm) ends 29, 31 of the heat
pipes are located either in refrigerator compartments, or in
refrigerator doors, or in proximity to the compartments whereto
cooling capacity to be delivered. To enhance heat transfer the warm
ends of the heat pipes may be equipped with fins. Fans 33, 35 may
improve temperature distribution in the compartments also as
efficiency of the system.
[0033] Not all of the refrigerator compartments are cooling
recipients acquiring cooling potential delivered by heat pipes.
Besides of cold plate sections transferring cooling to heat pipes
FIG. 1 depicts section 19 that is a regular evaporating section
that may be installed in an internal (relative to the refrigerator
cabinet) cooling compartment or connected to the internal cooling
compartment with air passages.
[0034] FIG. 2 shows a heat pipe 21 of FIG. 1. As an example, the
heat pipe depicted in FIG. 2 consists of 5 hermetically sealed
tubes 42. Each tube contains heat pipe media that condenses in the
cold ends 25 and evaporates in the warm ends 29. Condensed media
returns to the warm end either by gravity force or through
capillary action. A wick, or sintered metal powder, or a series of
grooves parallel to the pipe axis, or other means can be used to
achieve capillary effect. Cold end of each individual pipe is
connected to others with brackets 44 and 46. Bracket 46 is to be
attached to the cold plate surface with, for example, screws
protruded through holes 48 to position the cold heat pipe end in
heat transfer and structural communications with the cold plate.
Bracket 44 could be covered with insulating material to prevent
moisture condensation on the surface. At the opposite (warm) end 29
of the heat pipe individual tubes are spaced from each other and
provided with fins to enhance air to tubes heat transfer.
[0035] There are different types of heat pipes to use in
refrigerator. Each heat pipe may consist from several or only one
tube. Internal surface of tubes may be smooth and without a wick,
if the cold end of heat pipe is above the warm end and gravity
provides satisfactory return of the heat pipe liquid media to the
warm end. At least a part of the heat pipe tube could be flexible
allowing bending and twisting of the heat pipe. There are several
well-known companies designing and manufacturing different heat
pipes: Thermacore, Heat Pipe Technology, Noren Products, etc.
[0036] FIG. 3 shows schematics of a refrigerator with four
compartments and sealed system according to FIG. 1. Four
compartments include an internal freezing compartment 50, machine
compartment 52 located under the freezing compartment 50, internal
refrigerating compartment 54 above the freezing compartment 50, and
external compartment 56. A refrigerator cabinet comprises from side
walls 58, 60, back wall 62, top 64, and bottom 66. Machine
compartment houses sealed system parts (see FIG. 1): compressor 1,
condenser 3 with fan 5, 3-way valve 9, capillary tubes 11, 13. A
water valve, dryer 7, and, at least, a part of a control system are
also may be located in the machine compartment (these parts are not
shown in FIG. 3). Internal freezing compartment 50 is provided with
cooling by evaporating section 19 with a fan 70 positioned behind a
cover (not shown) in freezing compartment 50. Cold plate 15 is
inside of the refrigerator cabinet, on the top of compartment 50.
Cold plate 15 is connected to the cold end 25 of heat pipe 21. The
connection is accessible from inside of the refrigerator. Another
cold plate 17 is on the side of freezing compartment 50 and
connected to the cold end 23 of heat pipe 27. The connection is
accessible from outside of the refrigerator cabinet. Each cold
plate, excluding the heat transfer surface wherein the cold end of
heat pipe is attached, may be foamed in refrigerator wall or maybe
simply attached to this wall.
[0037] Heat pipe 21 provides cooling to the internal refrigerating
compartment 54. Cooling to the external compartment 56 is delivered
by heat pipe 23. Fasteners attach cold ends 25, 27 of the heat
pipes to cold plates 15, 17. Warm ends 29, 31 of the heat pipes
with fans 33, 35 are installed in the compartments behind the
covers (not shown). Filled with phase change media tubes connect
cold and warm ends of the heat pipes and may be foamed in the
compartment walls, or located behind the cover. Air pumped by fans
33 and 35 through the warm ends of heat pipes deliver heat to the
pipe media evaporating liquid media while absorbing heat from air.
Thus, air exits warm end of the heat pipe with lower temperature
providing cooling to the compartments. Evaporated heat pipe media,
in turn, condenses in the cold end of the heat pipe rejecting
absorbed from the warm end heat to the cold plate.
[0038] Each compartment may have either an individual control or
control connected to the main control board of the refrigerator. In
case of individual control a signal from a thermistor or a
thermocouple monitoring compartment temperature (not shown) stops
the fan when the compartment temperature drops below a
predetermined or set temperature level. Lack of air circulation
through the warm end of the heat pipe stops or greatly decreases
delivery heat to the cold end of the heat pipe that, in turn,
decreases refrigerant evaporation inside of the cold plate and
reduces evaporating pressure and temperature. The cold plate
surface temperature also drops down. Thermistor or thermocouple
attached to the cold plate or cold plate vicinity (not shown) sends
signals to the main refrigerant control board that together with a
timer gets both temperature and derivative of the temperature
change. When either temperature drops below a predetermined level
or pace of temperature reduction exceeds a predetermined level,
control sends a command to stop refrigerant flow through the cold
plate that could be done either switching the 3-way valve position
or stopping the compressor. In case of a multi-speed compressor
and/or multi-speed fan instead of stopping the speed of compressor
and fan could be reduced. On the contrary, when the compartment
temperature increases above some level the valve turns in the
position to deliver refrigerant to the corresponding cold plate and
compressor and/or fan speed is increased depending on the control
algorithm. Individual control of compartments 54, 56 allows
avoiding additional AC and DC electrical connections of these
compartments with the main control board.
[0039] Individual for each 54 and 56 compartments electrical cord
(not shown) maybe plugged in an electrical outlet providing
compartment illumination, the fan drive, and temperature, fan and
lights control.
[0040] In an alternative design compartment 54 or both compartments
50 and 54 are external compartments. In this design the
refrigerator cabinet (machine compartment 52) contains elements of
sealed system, control system, and some auxiliary parts. External
compartments may be manufactured separately from the refrigerator
cabinet and later connected to the cabinet by fasteners. Same as
compartment 56 with heat pipe 23 any external compartment could
become an additional refrigerating compartment, or a kimchi
compartment, an ice making compartment, or a compartment for other
cooling applications. Additional compartments can be attached to
the top, bottom, or any side of the refrigerator. The height,
depth, and width of fully assembled refrigerator may vary. If there
is no need in additional compartment this compartment as, for
example, compartment 56 could be removed from refrigerator
temporarily or permanently. If there is not a compartment, a
corresponding cold plate heat transfer surface (pos. 17 in FIG. 3)
shall be covered with insulation to avoid sweat. The cold plate
could be recessed below the compartment external surface a way the
cold plate covered with insulation creates a flat surface with the
rest of the wall.
[0041] In an alternative design cold plate section of the
evaporator could be installed in the upper part instead of the
lower part of refrigerator, the way that attached to the cold plate
the cold end of the heat pipe is above the warm end. Thus,
condensed heat pipe media may move to the warm end only by gravity
force like in a thermosiphon that, in turn, simplifies the heat
pipe.
[0042] In many well-known refrigerator brands like Sub Zero,
Kitchen Aid, Monogram, etc. the machine compartment is located at
the top. It makes positioning cold plate above the compartment
wherein cooling is to be delivered especially simple and
convenient. Another application of heat pipe in a refrigerator is
in delivering cooling capacity to an icemaker or/and ice storage
bin located in a refrigerating or freezing compartment. In some
refrigerators icemaker and ice bin can be enclosed in a special
ice-making section separated from the rest of the compartment, in
others an icemaker may not require separation from the compartment.
Examples of icemakers wherein a heat pipe delivers cooling capacity
to freeze water and preserve ice from melting are depicted in FIGS.
4, 5. FIG. 4 demonstrates schematics of a bottom mount refrigerator
100. There are 2 main compartments in refrigerator 100:
refrigerating compartment 102 with door 104 and freezing
compartment 106 with door 108. There is also an ice producing
apparatus, for example, icemaker schematically depicted in position
110. The icemaker can be installed in any part of the refrigerator
including the refrigerating compartment, or the refrigerating
compartment door, or the freezing compartment, or the freezing
compartment door. In FIG. 4 ice maker 110 is installed in the
refrigerating compartment door 104. In this arrangement the
icemaker within door 104 is enclosed in enclosure 112. Ice storage
bin 116 is in the same enclosure. An ice dispenser (not shown) is
on the other part of the door. Ice dispenser delivers ice to a
customer from ice bin 116 without the door opening. Ice dispenser
can be one of well-known designs that are in the most domestic
refrigerators like GE, Whirlpool, Sub Zero, etc.
[0043] An evaporator of the refrigeration sealed system includes
cold plate 120 and conventional evaporating section 124 connected
in series. Liquid refrigerant expanded after condenser in a cap
tube (not shown) flows through cold plate 120. After the cold plate
wherein a part of liquid refrigerant evaporates refrigerant flows
to the evaporating section 124. Bold dash lines with arrows in FIG.
4 demonstrate refrigerant flowing to the cold plate and from cold
plate to the evaporating section. After evaporating in evaporating
section 124 vapor refrigerant returns to compressor (not shown).
Evaporating section 124 provides cooling capacity to freezing
compartment 106 while cold plate 120 supplies the icemaker and ice
bin with cooling delivering this cooling with a heat pipe. Heat
pipe consists of cold end 128, warm end 122, and connecting tube
127 transporting vapor and liquid media between cold and warm
ends.
[0044] The icemaker includes a body with an ice making cavity
having a surface for receiving water and freezing water to ice.
Cold end 128 of the heat pipe is attached to cold plate 120 to
receive cooling from the cold plate and condense media vapor inside
of cold end 128. Warm end 122 is connected to the icemaker a way
that the warm end of the heat pipe through the icemaker body is in
heat transfer contact with the surface of the cavity delivering low
temperature potential to water to be frozen in the icemaker 110.
Besides of freezing water cold icemaker body provides cooling to
keep ice from thawing in the ice storage bin. To enhance cooling
supply to the ice bin an additional heat pipe section next to the
ice bin can be employed. Small fan assistance may also be useful to
transfer cooling potential from the icemaker to the ice bin. While
water and ice absorb cooling from the heat pipe, liquid media in
the warm end of the heat pipe evaporates and moves to the cold end
to be condensed. If gravity allows sufficient liquid media flow to
the warm end, the heat pipe can be simplified to a
thermosiphon.
[0045] An insulation pad 130 above the heat pipe cold end covers
both heat pipe cold end and the cold plate preventing sweat and
accidental touching of cold metal. Tubing 127 is also insulated
preventing sweat and accidental cold burns. Besides of connection
in series cold plate 120 may also be installed in parallel with
evaporating section 124 or connected to the evaporating section by
series-parallel refrigerant lines.
[0046] In FIG. 4 cold plate 120 is accessible from outside of the
refrigerating compartment, more particularly from the top of
refrigerator 100. In an alternative design the cold plate may be
installed on the outside wall 126 close to the edge where the door
hinges are located. The cold plate also could be installed inside
of any compartment or on any side or even on the back of the
refrigerator. Tubing 127 connecting the cold and warm ends of the
heat pipe may go through a hinge 132 of door 104. There are
different methods of designing connection between the heat pipe and
cold plate 120 allowing easy opening of door 104 and possibility to
disassemble the door from the refrigerator cabinet. In design
depicted in FIG. 4 tubing 127 includes a flexible section. Design
of the heat pipe with a flexible section can be close to designs
that Thermacore and several other companies use manufacturing heat
pipes with flexible sections.
[0047] Another use of heat pipe is in a refrigerator with icemaker
located inside of a refrigerating or freezing compartment. FIG. 5
shows same as in FIG. 4 bottom mount refrigerator 100 but with an
ice-making enclosure 112 and ice storage bin 116 inside of the
refrigerating compartment 102. The icemaker includes a body with an
ice making cavity for receiving water and freezing water to ice.
Same as with icemaker in the door, surface of the cavity is in heat
transfer communications with heat pipe warm end 122. There are
several ways to achieve a good heat transfer contact between the
heat pipe warm end and the cavity surface. Tubes of the heat pipe
warm end depicted in FIG. 5 may be molded into the icemaker body,
or these tubes can be wrapped around the body, or passed through
holes in the icemaker body. Flat or rounded conductive piece with
same profile as the corresponding icemaker part can be attached to
the heat pipe warm end and connected the ice making cavity.
[0048] Same as in refrigerator in FIG. 4 bold dash lines with
arrows show refrigerant flowing to the cold plate and from cold
plate to the evaporating section.
[0049] The warm end of the heat pipe is connected with cold end 128
by tubes 127 transporting heat pipe liquid media to the warm end
and vapor to the cold end. Cold end 128 is connected with fasteners
or springs to the cold plate 120 that is a part of the
refrigeration sealed system described above. Heat transfer surface
of the cold plate is accessible to be connected or disconnected
with heat pipe cold end 128 from inside of the refrigerator
cabinet. In FIG. 5 the cold plate is on the top of the compartment.
However, it may be positioned on the bottom or compartment's
sides.
[0050] A layer of heat transfer grease 134 can be used to improve
heat transfer between heat transfer surface of cold plate 120 and
heat pipe cold end 128. Ice storage bin 116 slides underneath of
ice making enclosure 112. To prevent ice cubes from fusing the ice
bin could be insulated. The bin is designed a way that gravity
moves ice to hole 136. When door 104 closed and ice is to be
delivered to a customer, hole 136 is opened against the opening 140
in ice chute 138. When the door is opened or an ice dispenser is
not activated, the hole 136 is obstructed not allowing ice cubes
dropping down into the refrigerating compartment. Well known
mechanical or electromechanical means maybe used for obstruction of
hole 136. Because of highly efficient heat transfer from cold plate
to the heat pipe and further to the ice making cavity, icemaker can
be relatively small. It allows locating ice-making cabinet next to
the wall as shown in FIG. 5 and making it narrow. Thus, icemaker
wouldn't considerably obstruct an access to food in the
refrigerating compartment.
[0051] An ice dispenser (not shown) is on the other part of the
door 104. To simplify the ice chute ice dispenser may be located on
the periphery of the door against the chute. Control of icemaker
operations has several steps. Besides of controlling icemaker body
temperature another way is the cold plate temperature control.
While icemaker is in freezing water operation control directs, at
least, a part of refrigerant through cold plate 128. When water in
the icemaker becomes frozen heat transfer to the heat pipe warm end
considerably reduces, this decreases delivery of heat pipe media
vapor to the cold end of the heat pipe and diminishes refrigerant
evaporation in the cold plate. This, in turn, decreases evaporating
pressure and temperature. The cold plate surface temperature drops
down. Thermistor or thermocouple attached to the cold plate sends
signals to the control board that with an assistance from a timer
gets both temperature or/and derivative of the temperature change.
When either temperature drops below a predetermined level, or pace
of temperature reduction exceeds a predetermined level, control
sends a command to cut refrigerant flow through the cold plate and
activate an icemaker heater (not shown). After ice is detached and
extracted from the ice making cavity and a new portion of water is
brought to the icemaker, refrigerant flow to the cold plate is
restored. When ice bin is filled, mechanical, electrical, or
photoelectrical device stops ice making operation. Still there is a
necessity to keep temperature in the ice bin several degrees below
0 deg. C. or 32 deg. F. To provide ice making cabinet with cooling
capacity combination of cold plate-heat pipe-icemaker still will be
in periodical operation but without water delivering to the ice
making cavity. To enhance cooling supply to the ice bin an
additional heat pipe section next to the ice bin can be employed.
Small fan assistance may also be useful.
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