U.S. patent application number 14/487476 was filed with the patent office on 2015-09-03 for single evaporator refrigeration system for multi-compartment refrigerator appliance with isolated air flows.
This patent application is currently assigned to WHIRLPOOL CORPORATION. The applicant listed for this patent is Whirlpool Corporation. Invention is credited to BRENT A. JUNGE.
Application Number | 20150247662 14/487476 |
Document ID | / |
Family ID | 38947874 |
Filed Date | 2015-09-03 |
United States Patent
Application |
20150247662 |
Kind Code |
A1 |
JUNGE; BRENT A. |
September 3, 2015 |
Single Evaporator Refrigeration System For Multi-Compartment
Refrigerator Appliance With Isolated Air Flows
Abstract
A refrigeration appliance has a cabinet having a first
compartment, a second separate compartment and a refrigeration
system including a compressor, an evaporator and a condenser. The
evaporator is associated with the first compartment to lower a
temperature of the first compartment air. A heat exchanger is
exposed to the temperature of the first compartment and has a
surface area exposed to second compartment air. An air moving
device is associated with the second compartment to direct a flow
of second compartment air over the heat exchanger surface area and
circulate the second compartment air within the second compartment.
The cabinet, compartments and heat exchanger are configured such
that first compartment air is completely isolated from second
compartment air.
Inventors: |
JUNGE; BRENT A.;
(Evansville, IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Whirlpool Corporation |
Benton Harbor |
MI |
US |
|
|
Assignee: |
WHIRLPOOL CORPORATION
Benton Harbor
MI
|
Family ID: |
38947874 |
Appl. No.: |
14/487476 |
Filed: |
September 16, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11457157 |
Jul 13, 2006 |
8863537 |
|
|
14487476 |
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Current U.S.
Class: |
62/443 ;
62/414 |
Current CPC
Class: |
F25D 2317/0682 20130101;
F25D 2400/06 20130101; F25D 11/02 20130101; F25D 17/065 20130101;
F25D 2700/12 20130101; F25D 17/067 20130101; F25D 2700/122
20130101; F25B 39/02 20130101; F25D 17/08 20130101 |
International
Class: |
F25D 17/06 20060101
F25D017/06; F25D 11/02 20060101 F25D011/02 |
Claims
1. A refrigeration appliance comprising: a cabinet having a first
compartment and a second separate compartment, a refrigeration
system including a compressor, an evaporator and a condenser, the
evaporator being associated with the first compartment to lower a
temperature of the first compartment air, a heat exchanger
comprising a plate in direct contact with the evaporator, the heat
exchanger being exposed to the temperature of the first compartment
and having a surface area in the form of a flat plate with a
plurality of ribs exposed to second compartment air, an air moving
device associated with the second compartment to direct a flow of
second compartment air over the heat exchanger surface area and
circulate the second compartment air within the second compartment,
the air moving device arranged to operate at a speed to produce a
volume flow rate of air greater than 8 cfm and not greater than
about 25 cfm in the second compartment, the ribs on the plate being
oriented in a direction of air flow of the second compartment air
over the plate, the cabinet, compartments and heat exchanger being
configured such that first compartment air is completely isolated
from second compartment air.
2. The refrigeration appliance of claim 1, wherein the heat
exchanger comprises an air passage for the first compartment air
and a separate air passage for the second compartment air.
3. The refrigeration appliance of claim 1, wherein the heat
exchanger comprises a plate having one side in thermal contact with
the first compartment, the plate being thermally shielded from the
second compartment.
4. A refrigeration appliance comprising: a cabinet having a first
compartment and a second separate compartment, a refrigeration
system including a compressor, an evaporator and a condenser, a
first fan in air flow communication with the first compartment to
direct a flow of first compartment air over the evaporator and
circulate the first compartment air within the first compartment to
lower a temperature within the first compartment, a heat exchanger
comprising a metal plate in direct contact with the evaporator,
wherein the metal plate has a first surface area in thermal
communication with the first compartment and has a second surface
area exposed to second compartment air, a second fan in air flow
communication with the second compartment to direct a flow of
second compartment air over the heat exchanger second surface area
and circulate the second compartment air within the second
compartment, the second fan arranged to operate at a speed to
produce a volume flow rate of air in the range of 20 to 25 cfm in
the second compartment, the second surface area being provided with
a plurality of ribs oriented in a direction of air flow of the
second compartment air over the plate, the cabinet, compartments
and heat exchanger being configured such that no surface area or
space is exposed to both first compartment air and second
compartment air.
5. The refrigeration appliance of claim 4, wherein the heat
exchanger comprises an air passage for the first compartment air
and a separate air passage for the second compartment air.
6. The refrigeration appliance of claim 4, wherein the heat
exchanger comprises a plate having one side in thermal contact with
the first compartment, the plate being thermally shielded from the
second compartment.
7. A refrigeration appliance comprising: a cabinet having a first
compartment and a second separate compartment, a refrigeration
system including a compressor, an evaporator and a condenser, the
evaporator being associated with the first compartment to lower a
temperature of the first compartment air, an air to air heat
exchanger having a plurality of air passages therein, with a first
plurality of the air passages communicating with first compartment
air and a second plurality of the air passages communicating with
second compartment air, an air moving device associated with the
second compartment to direct a flow of second compartment air
through the second plurality of the air passages and circulate the
second compartment air within the second compartment, the air
moving device arranged to operate at a speed to produce a volume
flow rate of air greater than 8 cfm and not greater than about 25
cfm in the second compartment, the cabinet, compartments and heat
exchanger being configured such that first compartment air is
completely isolated from second compartment air.
8. The refrigeration appliance of claim 7, wherein the air passages
in the heat exchanger for both the first compartment air and the
second compartment air comprise parallel tubes.
9. The refrigeration appliance of claim 7, wherein the air passages
in the heat exchanger for both the first compartment air and the
second compartment air comprise parallel channels.
10. The refrigeration appliance of claim 7, wherein the air
passages in the heat exchanger for both the first compartment air
and the second compartment air comprise side by side tubes.
11. The refrigeration appliance of claim 7, wherein the air
passages in the heat exchanger for both the first compartment air
and the second compartment air comprise side by side channels.
12. The refrigeration appliance of claim 7, wherein the heat
exchanger is located at a wall separating the first compartment
from the second compartment.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application is a divisional application of U.S. patent
application Ser. No. 11/457,157, filed on Jul. 13, 2006, entitled
"SINGLE EVAPORATOR REFRIGERATION SYSTEM FOR MULTI-COMPARTMENT
REFRIGERATOR APPLIANCE WITH ISOLATED AIRFLOWS," the disclosure of
which is hereby incorporated herein by reference in its
entirety.
BACKGROUND OF THE INVENTION
[0002] This invention relates generally to combined
refrigerator/freezer appliances.
[0003] Combined refrigerator/freezer appliances typically have two
or more compartments that are refrigerated to differing
temperatures, one being chilled to a temperature well below the
freezing temperature of water, such as around 0.degree. F. and the
other being chilled to a below ambient temperature, which is above
freezing, such as around 40.degree. F. To chill the two different
compartments to these temperatures, a refrigeration system is
typically employed which includes one or two evaporator
components.
[0004] In a single evaporator system, such as that disclosed in
U.S. Pat. No. 5,490,395, the evaporator is located in, or in close
communication with the freezer compartment, and the evaporator is
chilled to below the desired temperature for the freezer
compartment. Air is circulated over the evaporator to chill the
freezer compartment. To cool the refrigerator or fresh food
compartment, air is ducted out of the freezer compartment and is
circulated through the fresh food compartment, and then returned to
the freezer compartment. A separate fan is usually provided for the
fresh food compartment air circulation system along with baffles
for permitting or preventing the flow of sub-freezing air into the
fresh food compartment. Problems that result from single evaporator
systems are that the significantly higher humidity levels in the
fresh food compartment are transferred to the freezer compartment
as the air is circulated between the two compartments, reducing the
desired humidity level in the fresh food compartment and increasing
a build-up of frost in the freezer compartment, and food odors are
also transmitted between the two compartments.
[0005] In a dual or multi-evaporator refrigerator/freezer
appliance, such as disclosed in U.S. Pat. No. 5,465,591, a separate
evaporator is used for each compartment, which addresses some of
the problems listed above since the air in each compartment is
isolated from the air in other compartments, however, there are
significant increased costs for two separate evaporators and
possibly two complete refrigeration systems. Also, there are more
joints in the cooling system that may fail over time, and the
addition of another evaporator and refrigerant system for that
evaporator, results in a loss of at least 0.3 to 0.5 cubic feet
from the food storage space in the compartments. Also, proving two
evaporators results in increased tooling costs and factory
complexity.
[0006] A single evaporator system is disclosed in U.S. Pat. No.
5,375,428 in which the single evaporator is positioned in the
mullion between the freezer compartment and the fresh food
compartment. Air is alternately circulated over the evaporator from
one of the two compartments, such that the mixing of air between
the two compartments is reduced, although not eliminated. This
system requires that the evaporator be operated at different
pressures, and hence different temperatures, depending on which of
the two compartments is being cooled, thereby increasing the
complexity of the system and control. Also, in such a system, only
one compartment may be cooled at a time, even when both
compartments may be demanding cooling.
SUMMARY OF THE INVENTION
[0007] The present invention addresses the problems associated with
the prior art and provides a refrigeration appliance with a cabinet
having a first compartment, a second separate compartment and a
refrigeration system including a compressor, an evaporator and a
condenser. The evaporator is associated with the first compartment
to lower a temperature of the first compartment air. A heat
exchanger is exposed to the temperature of the first compartment
and has a surface area exposed to second compartment air. An air
moving device is associated with the second compartment to direct a
flow of second compartment air over the heat exchanger surface area
and circulate the second compartment air within the second
compartment. The cabinet, compartments and heat exchanger are
configured such that first compartment air is completely isolated
from second compartment air.
[0008] In an embodiment, the heat exchanger includes a plate in
direct contact with the evaporator.
[0009] In an embodiment, the heat exchanger comprises an air
passage for the first compartment air and a separate air passage
for the second compartment air.
[0010] In an embodiment, the heat exchanger comprises an air
passage for only second compartment air.
[0011] In an embodiment, the heat exchanger comprises a plate
having one side in thermal contact with the first compartment, the
plate being thermally shielded from the second compartment.
[0012] In an embodiment, a first temperature sensor is provided in
the first compartment in communication with a control to operate
the first air moving device and the refrigeration system, a second
temperature sensor is provided in the second compartment in
communication with the control to operate the second air moving
device, and operation of the first air moving device is independent
from operation of the second air moving device.
[0013] In an embodiment, the heat exchanger is located at a wall
separating the first compartment from the second compartment.
[0014] In an embodiment, the invention provides a refrigeration
appliance including a cabinet having a first compartment, a second
separate compartment, and a refrigeration system including a
compressor, an evaporator and a condenser. A first fan is in air
flow communication with the first compartment to direct a flow of
first compartment air over the evaporator and circulate the first
compartment air within the first compartment to lower a temperature
within the first compartment. A heat exchanger is provided having a
metal plate with a first surface area in thermal communication with
the first compartment and having a second surface area exposed to
second compartment air. A second fan is in air flow communication
with the second compartment to direct a flow of second compartment
air over the heat exchanger second surface area and circulate the
second compartment air within the second compartment. The cabinet,
compartments and heat exchanger are configured such that no surface
area or space is exposed to both first compartment air and second
compartment air.
[0015] In an embodiment, the invention provides a refrigeration
appliance including a cabinet having a first compartment, a second
separate compartment, and a refrigeration system including a
compressor, an evaporator and a condenser. A first fan is located
in the first compartment to direct a flow of first compartment air
over the evaporator and circulate the first compartment air within
the first compartment to lower a temperature within the first
compartment. A heat exchanger is located in a wall separating the
first compartment and the second compartment having a metal plate
with a first surface area in thermal communication with the first
compartment and having a second surface area exposed to second
compartment air. A second fan is located in the second compartment
to direct a flow of second compartment air over the heat exchanger
second surface area and circulate the second compartment air within
the second compartment. The cabinet, compartments and heat
exchanger are configured such that no surface area or space is
exposed to both first compartment air and second compartment
air.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a front elevational view of a refrigeration
appliance incorporating the present invention, with the doors
removed for clarity.
[0017] FIG. 2 is a partial front sectional view of the plenum wall
in a refrigeration appliance with a second embodiment of the
invention.
[0018] FIG. 3 is a partial front sectional view of the plenum wall
in a refrigeration appliance with a third embodiment of the
invention.
[0019] FIG. 4 is a side sectional view of the plenum wall taken
generally along the line IV-IV of FIG. 3
[0020] FIG. 5 is a partial front sectional view of the plenum wall
in a refrigeration appliance with a fourth embodiment of the
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] The present invention provides a refrigeration appliance 20
with a cabinet 22 having a first compartment 24, a second separate
compartment 26 and a refrigeration system 28. The refrigeration
appliance 20 in which the invention finds particular utility is a
side-by-side refrigerator-freezer, in which the first compartment
24 is a freezer compartment and the second compartment 26 is a
fresh food compartment. The invention may also be used in other
appliances, such as where the freezer compartment is located above
or below the fresh food compartment. Also, although the preferred
refrigeration appliance 20 includes a compartment maintained at a
temperature below freezing and a compartment above freezing, the
invention could also be utilized in an appliance where both
compartments are maintained below freezing or both compartments are
maintained above freezing.
[0022] The refrigeration system 28 may be of conventional design
and include a compressor 30, an evaporator 32 and a condenser 34.
The evaporator 32 is associated with the first compartment 24 to
lower a temperature of first compartment air 38. For example, the
evaporator 32 may be located in a passage 36 through which a flow
of first compartment air 38 is directed by means of an air moving
device 40, such as a fan. The first compartment air 38 is
introduced into the first compartment 24 via an inlet 39 from the
passage 36 and flows back to the evaporator 32 via a return 41. In
other embodiments, the evaporator 32 may have a component that is
merely exposed to the interior of the first compartment 24 and a
general air flow created by an air moving device within the first
compartment will effect a heat transfer at the evaporator. In other
embodiments, natural convection currents may move the air in the
first compartment 24 and over the evaporator 32, without the need
for a separate air moving device associated with the first
compartment.
[0023] A heat exchanger 42 is exposed to the temperature of the
first compartment 24 and has a surface area 44 exposed to second
compartment air 45. As illustrated in the embodiment shown in FIG.
1, the heat exchanger 42 may include a metal plate 46 that lies
against an inside surface 47 of a center mullion wall 48. In this
embodiment, the plate has one side 50 in thermal contact with the
first compartment 24. The heat exchanger 42 may include an air
passage 52 located in the center mullion wall 48 which communicates
with the second compartment 26, such as by an inlet vent 54 and a
return vent 56. In this embodiment, the heat exchanger 42 includes
an air passage 52 for only second compartment air 45. Other
embodiments discussed below provide air passages for both first 38
and second 45 compartment air. The heat exchanger 42 may also be
provided with a condensation drain 57 to permit any collected
condensation from the heat exchanger to be removed. The
condensation drain 57 may lead to a common collection or storage
area with condensation drained from the evaporator 32, or a
separate storage area may be provided.
[0024] An air moving device 58 is associated with the second
compartment 26 to direct a flow of second compartment air 45 over
the heat exchanger surface area 44 and circulate the second
compartment air within the second compartment by drawing the second
compartment air in through the return vent 56 and dispensing the
second compartment air into the second compartment through the
inlet vent 54. For example, the air moving device 58 may be a fan
that operates at a single speed, or it may be a variable speed
fan.
[0025] The cabinet 22, compartments 24, 26 and heat exchanger 42
are configured such that first compartment air 38 is completely
isolated from second compartment air 45. That is, the air flow
passage 52 for the second compartment air 45 does not come into
contact with any surface contacted by the first compartment air 38,
and there is no passage or area through which both first
compartment air and second compartment air flow, even at different
times.
[0026] The plate 46 may be a flat plate, or it may be provided with
ribs or fins, preferably oriented in a direction of air flow along
the plate, to increase the effective surface area contacted by the
second compartment air 45.
[0027] The plate 46 may be thermally shielded from the second
compartment 26, such as by a layer of insulation material 59, or by
being positioned away from the second compartment. For example, the
air passage 52 may be formed by an expanded polystyrene material
which both forms that passage and provides heat insulation between
the plate 46 and the second compartment 26. By providing the
insulation, a second compartment side 61 of the mullion wall 48
will remain at close to the temperature of the second compartment
26, rather than the temperature of the plate 46, thereby reducing
the possibility of formation of condensation on the mullion wall.
Also, by providing the insulation 59, cooling of the second
compartment 26 by the heat exchanger 42 will occur only when second
compartment air 45 is being moved over the plate 46.
[0028] A first temperature sensor 60 may be provided in the first
compartment 24 in communication with a control 62 to operate the
first air moving device 40 and the refrigeration system 28. A
second temperature sensor 64 may be provided in the second
compartment 26 in communication with the control 62 to operate the
second air moving device 58. Operation of the first air moving
device 40 may be independent from operation of the second air
moving device 58, such that both air moving devices may be
operating simultaneously, or one or both may be turned off at any
given time, depending on the temperature sensed by the temperature
sensors 60, 64 located in each compartment 24, 26.
[0029] The second air moving device 58 may be operated at different
speeds, depending on the temperature sensed by the second
temperature sensor 64, or the differential between the sensed
temperature and a desired temperature entered in the control 62 by
a user. Applicant has found that a higher volume flow rate of air,
such as on the order of 20 to 25 cfm, may be provided in the second
compartment 26, such as a fresh food compartment, than was
practical in prior refrigerator appliances which typically has
volume flow rates of 5 to 8 cfm. This higher volume air flow rate
results since the temperature of the heat exchanger 42 contacted by
the second compartment air 45 is not as low as the temperature in
the first compartment 24, and the transfer of heat is less rapid
when utilizing the heat exchanger as opposed to circulating air
from the first compartment 24 through the second compartment 26.
The higher volume flow rate is advantageous in that it helps to
prevent condensation from occurring on surfaces in the second
compartment 26, and helps in removing any condensation that does
occur in the second compartment. That condensation is transferred
to the heat exchanger and is removed through the condensation drain
57 as described above.
[0030] In an embodiment, as illustrated in FIG. 2, the heat
exchanger 42 may comprise a plate 66 that is exposed to direct air
flow from both the second compartment 26, as well as the first
compartment 24, although on different sides of the plate. An air
flow passage 68 may be provided for the second compartment air 45,
as well as an air flow passage 70 for the first compartment air 38.
The two air flow passages 68, 70 remain isolated from one another
so that there will be no mixing of first compartment air 38 and
second compartment air 45.
[0031] In an embodiment, as illustrated in FIGS. 3 and 4, again
separate air flow passages 2, 74 may be provided for the second
compartment air 45 and the first compartment air 38. This heat
exchanger 42 may be constructed as a conventional air to air heat
exchanger, in which the heat from the second compartment air 45 is
transferred to and absorbed by the first compartment air 38,
without any mixing of the two air flows. This heat exchanger may be
constructed in the form of side by side parallel channels, tubes,
or other known arrangements for air to air heat exchangers.
[0032] In an embodiment, as illustrated in FIG. 5, the heat
exchanger 42 includes a plate 76 in direct contact with the
evaporator 32. The evaporator 32 may be positioned in abutting
relationship with a wall 78 separating the first 24 and second 26
compartments, which provides several benefits. For example, the
efficiency of the heat transfer from the plate 76 is increased,
since the transfer occurs by conduction directly to the evaporator,
in addition to convection and radiation. During a defrosting
operation of the evaporator 32, when the temperature of the
evaporator is elevated to remove frost from the evaporator, the
plate 76 would also be heated, thereby removing any frost build-up
on the plate.
[0033] The present invention, by maintaining an isolation between
the first compartment air 38 and the second compartment air 45,
allows a higher level of humidity to be maintained in the second
compartment 26, when it is a fresh food compartment, than in the
first compartment 24 when it is a freezer compartment, which allows
for a greater refrigerated lifespan for fresh foods. This also
allows for a low level of humidity to be maintained in the first
compartment 24, which, when operated as a freezer compartment, will
reduce the build-up of frost in the first compartment and on the
evaporator 32, allowing for a higher operating efficiency, and
allowing for other materials, such as glass shelves, to be used in
the first compartment. Condensation in the second compartment, when
a fresh food compartment is reduced by allowing a greater and
nearly continuous flow of air via the second air moving device 58,
if need be, since any collected condensation in the second
compartment will be evaporated and transported by the moving second
compartment air 45, and the moisture will be recondensed at the
cooler surface of the heat exchanger 42
[0034] The transfer of odors from one compartment to the other is
greatly reduced or eliminated by having the first compartment air
38 and the second compartment air 45 isolated from each other and
by not having any areas or surfaces contacted by both first
compartment air and second compartment air, even if not
simultaneously.
[0035] The present invention has been described utilizing
particular embodiments. As will be evident to those skilled in the
art, changes and modifications may be made to the disclosed
embodiments and yet fall within the scope of the present invention.
For example, various components could be utilized separately or
independently in some embodiments without using all of the other
components in the particular described embodiment. The disclosed
embodiment is provided only to illustrate aspects of the present
invention and not in any way to limit the scope and coverage of the
invention. The scope of the invention is therefore to be limited
only by the appended claims.
[0036] As is apparent from the foregoing specification, the
invention is susceptible of being embodied with various alterations
and modifications which may differ particularly from those that
have been described in the preceding specification and description.
It should be understood that I wish to embody within the scope of
the patent warranted hereon all such modifications as reasonably
and properly come within the scope of my contribution to the
art.
* * * * *