U.S. patent application number 13/828246 was filed with the patent office on 2013-10-03 for heat sink for a condensing unit and method of using same.
This patent application is currently assigned to EMERSON CLIMATE TECHNOLOGIES, INC.. The applicant listed for this patent is EMERSON CLIMATE TECHNOLOGIES, INC.. Invention is credited to Roy J. Doepker, Stephen M. Seibel, Robert C. Stover.
Application Number | 20130255932 13/828246 |
Document ID | / |
Family ID | 48040040 |
Filed Date | 2013-10-03 |
United States Patent
Application |
20130255932 |
Kind Code |
A1 |
Doepker; Roy J. ; et
al. |
October 3, 2013 |
HEAT SINK FOR A CONDENSING UNIT AND METHOD OF USING SAME
Abstract
A condensing unit control module may be cooled using multiple
methods of cooling. A first method of cooling can be used to cool
the control module when a minimal or reduced amount of cooling is
needed, and a second method of cooling can be used when the control
module requires a larger or maximum amount of cooling. The first
method of cooling may include the use of air cooling. The second
method of cooling can be through working fluid cooling. The second
cooling method can supplement the first cooling method as the
cooling needs of the control module increase. The second cooling
method can be activated based upon a temperature of a heat sink, a
temperature of one or more components of the control module,
operating conditions of a heat pump system, ambient conditions,
and/or a temperature of the working fluid flowing throughout the
heat pump system.
Inventors: |
Doepker; Roy J.; (Lima,
OH) ; Seibel; Stephen M.; (Celina, OH) ;
Stover; Robert C.; (Versailles, OH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
EMERSON CLIMATE TECHNOLOGIES, INC. |
Sidney |
OH |
US |
|
|
Assignee: |
EMERSON CLIMATE TECHNOLOGIES,
INC.
Sidney
OH
|
Family ID: |
48040040 |
Appl. No.: |
13/828246 |
Filed: |
March 14, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61618244 |
Mar 30, 2012 |
|
|
|
Current U.S.
Class: |
165/287 ;
165/104.11; 165/122; 165/168; 165/96 |
Current CPC
Class: |
F25B 2400/071 20130101;
F25B 13/00 20130101; F24F 1/24 20130101; F25B 2700/21153 20130101;
F25B 2600/2507 20130101; F25B 2341/0661 20130101; F28D 15/00
20130101; F25B 49/022 20130101; F25B 5/00 20130101; F25B 31/006
20130101; F25B 2400/0409 20130101 |
Class at
Publication: |
165/287 ;
165/168; 165/122; 165/96; 165/104.11 |
International
Class: |
F28D 15/00 20060101
F28D015/00 |
Claims
1. A condensing unit housing a compressor, a control module
controlling operation of said compressor, and a heat sink in
heat-transferring relation with said control module, said control
module being in heat-transferring relation with a first fluid and a
second fluid, said first fluid selectively flowing through a fluid
passageway in said heat sink, said second fluid being a different
substance than said first fluid and in selective convective
heat-transferring relation with a heat-transferring member in
heat-transferring relation with said heat sink.
2. The condensing unit of claim 1, further comprising: a condenser
at least partially defining a cavity; a fan operable to direct a
flow of said second fluid through said condenser, and wherein said
compressor, said control module, said heat-transferring member and
said heat sink are disposed in said cavity.
3. The condensing unit of claim 2, wherein said fan operates
independently of an operating condition of said condenser.
4. The condensing unit of claim 1, further comprising a cooling
module operable to selectively route said first fluid discharged by
said compressor through said flow path to remove heat from said
control module.
5. The condensing unit of claim 4, wherein said cooling module
includes a valve disposed in said fluid conduit that selectively
allows said fluid conduit to direct said first fluid discharged by
said compressor into said fluid passageway.
6. The condensing unit of claim 5, wherein said valve is an
expansion device.
7. The condensing unit of claim 4, wherein said cooling module
includes a temperature sensing device and said cooling module
selectively routes said first fluid discharged by said compressor
through said fluid passageway based on an output of said
temperature sensing device.
8. The condensing unit of claim 4, wherein said cooling module a
temperature responsive valve operable to selectively allow said
first fluid discharged by said compressor into said fluid
passageway based on a temperature sensed by said temperature
responsive valve.
9. The condensing unit of claim 1, wherein an entirety of a flow of
said first fluid discharged by said compressor can flow through
said fluid passageway.
10. The condensing unit of claim 1, further comprising a first fan,
said first fan inducing a flow of said second fluid across said
heat-transferring member.
11. The condensing unit of claim 10, further comprising a condenser
at least partially defining a cavity; a second fan operable to
direct a flow of said second fluid through said condenser, and
wherein said compressor, said control module, said
heat-transferring member and said heat sink are disposed in said
cavity and said flow of said second fluid induced by said second
fan passes across said heat-transferring member, and said first fan
and said second fan can be operated independently of one
another.
12. A method of cooling a compressor control module comprising:
removing heat from the control module with a first cooling method
that transfers heat to a first fluid; and selectively supplementing
said first cooling method by removing heat from the control module
with a second cooling method that transfers heat to a second fluid
different than said first fluid while simultaneously removing heat
with said first cooling method.
13. The method of claim 12, wherein said first fluid is ambient air
and said second fluid is working fluid discharged by the
compressor.
14. The method of claim 12, wherein selectively supplementing said
first cooling method includes removing heat with said second method
based on a temperature, said temperature including at least one of
an ambient air temperature, a temperature of the control module, a
temperature of working fluid discharged by the compressor, and a
temperature of a heat sink in heat-transferring relation to the
control module.
15. The method of claim 12, wherein removing heat with said first
cooling method includes inducing an airflow through a condenser and
over a heat sink in heat-transferring relation with the control
module.
16. The method of claim 12, wherein removing heat with said first
cooling method includes inducing an airflow over a heat sink in
heat-transferring relation with the control module, the induced
airflow being independent of an operating condition of a
condenser.
17. The method of claim 12, wherein removing heat from the control
module with said second cooling method includes routing at least a
portion of working fluid discharged from the compressor through a
flow path in a heat sink in heat-transferring relation to the
control module.
18. The method of claim 12, wherein selectively supplementing
includes removing heat from the control module with said second
cooling method when the compressor is operating in a predetermined
range.
19. A method of cooling a compressor control module comprising:
inducing an airflow across a heat sink in heat-transferring
relation to the control module; transferring heat from the control
module to the airflow through said heat sink; selectively routing a
working fluid through a flow path in said heat sink in
heat-transferring relation to the control module; and transferring
heat from the control module to said working fluid when said
working fluid is flowing through said heat sink.
20. The method of claim 19, wherein selectively routing includes
selectively routing a condensed working fluid through said flow
path in said heat sink.
21. The method of claim 19, wherein selectively routing includes
selectively routing an entirety of a flow of working fluid
discharged by the compressor through said flow path in said heat
sink.
22. The method of claim 19, wherein selectively routing includes
selectively routing said working fluid through said flow path based
on a temperature of said working fluid.
23. The method of claim 19, wherein inducing said airflow includes
inducing said airflow during an entire time the compressor is
operating.
24. The method of claim 19, wherein inducing said airflow includes
inducing said airflow to flow through a condenser within which the
compressor and control module are disposed.
25. The method of claim 19, wherein inducing said airflow includes
inducing said airflow with a fan that operates independently from
operation of a condenser.
26. The method of claim 19, wherein selectively routing said
working fluid includes using an expansion valve to selectively
route and expand said working fluid in said flow path.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 61/618,244, filed on Mar. 30, 2012. The entire
disclosure of the above application is incorporated herein by
reference.
FIELD
[0002] The present disclosure relates to heating and
air-conditioning systems and, more particularly, to cooling
electrical components that drive the operation of the
compressor.
BACKGROUND
[0003] This section provides background information related to the
present disclosure and is not necessarily prior art.
[0004] Control modules, such as electronic devices, used in heating
and air-conditioning systems often require a reliable means to cool
their components. One such control module is a drive unit used with
a variable-speed compressor.
[0005] The control module may be required to be cooled to within a
specific temperature range or be maintained below a predetermined
temperature to ensure adequate component life, performance, and
reliability. The cooling needs of the control module can vary based
on the operating condition of the heating and air-conditioning
system. In situations where the cooling needs are not met, the
temperature of the control module may reach a maximum operating
temperature, which may trigger a sensor that shuts down the system
operation, causing a nuisance trip in the drive.
SUMMARY
[0006] This section provides a general summary of the disclosure,
and is not a comprehensive disclosure of its full scope or all of
its features.
[0007] In one form, the present disclosure provides a condensing
unit that houses a compressor, a control module and a heat sink.
The control module may control operation of the compressor. The
heat sink may be in heat-transferring relation with the control
module. The control module may be in heat-transferring relation
with a first fluid and a second fluid. The first fluid may
selectively flow through a fluid passageway in the heat sink. The
second fluid may be a different substance than the first fluid and
may be in selective convective heat-transferring relation with a
heat-transferring member in heat-transferring relation with the
heat sink.
[0008] In another form, the present disclosure provides a system
that may include a compressor, a heat sink, a fluid conduit, at
least one external heat-transferring member, and a control module.
The heat sink may include a flow path therethrough. The fluid
conduit may communicate with the heat sink flow path. The at least
one external heat-transferring member may be in heat-transferring
relation with the heat sink. The control module may be in
heat-transferring relation with the heat sink. The control module
may control operation of the compressor. The heat sink may transfer
heat from the control module to a fluid flowing over the
heat-transferring member and to a fluid flowing through the flow
path.
[0009] In another form, the present disclosure provides a method of
cooling a compressor control module. The method may include
removing heat from the control module with a first cooling method
that transfers heat to a first fluid. The method may also include
selectively supplementing the first cooling method by removing heat
from the control module with a second cooling method that transfers
heat to a second fluid different than the first fluid while
simultaneously removing heat with the first cooling method.
[0010] In another form, the present disclosure provides a method of
cooling a compressor control module that may include inducing an
airflow across a heat sink in heat-transferring relation to the
control module. The method may also include transferring heat from
the control module to the airflow through the heat sink. A working
fluid may be selectively routed through a flow path in the heat
sink in heat-transferring relation to the control module. Heat from
the control module may be transferred to the working fluid when the
working fluid is flowing through the heat sink.
[0011] In another form, the present disclosure provides a control
module that can be cooled using multiple methods of cooling. A
first method of cooling can be used to cool the control module when
a minimal or reduced amount of cooling is needed, and a second
method of cooling can be used when the control module requires a
larger or maximum amount of cooling. The use of multiple methods of
cooling the control module can be referred to as hybrid cooling.
The first method of cooling the control module can be through the
use of air cooling. The second method of cooling the control module
can be through working fluid cooling. The air cooling can be used
to provide a first level of cooling and the working fluid cooling
can be utilized when a greater degree of cooling is required. The
second cooling method can supplement the first cooling method as
the cooling needs of the control module increase. The second
cooling method can be activated based upon a temperature of a heat
sink, a temperature of one or more components of the control
module, operating conditions of a heat pump system, ambient
conditions, and/or a temperature of a working fluid flowing
throughout the heat pump system, by way of non-limiting
example.
[0012] Further areas of applicability will become apparent from the
description provided herein. It should be understood that the
description and specific examples are intended for purposes of
illustration only and are not intended to limit the scope of the
present teachings.
DRAWINGS
[0013] The drawings described herein are for illustration purposes
only and are not intended to limit the scope of the present
teachings in any way.
[0014] FIG. 1 is a cut-away perspective view of a condensing unit
having a compressor and control module therein that are cooled
according to the present teachings;
[0015] FIG. 2 is an enlarged perspective view of the compressor,
the control module, and the cooling components of FIG. 1;
[0016] FIG. 3 is a perspective view of the control module with the
cover removed;
[0017] FIG. 4 is a schematic representation of a heating and
air-conditioning system showing the working fluid cooling of the
control module according to the present teachings;
[0018] FIGS. 5 and 6 are schematic representations of heating and
air-conditioning systems including other working fluid cooling
configurations according to the present teachings;
[0019] FIGS. 7 and 8 are schematic representations of a heating and
air-conditioning system in the form of a heat pump shown in a
cooling mode and a heating mode, respectively, and showing the
working fluid cooling of the control module according to the
present teachings;
[0020] FIG. 9 is a graph illustrating a possible
compressor-operating envelope and showing where the control module
is air cooled and working fluid cooled according to the present
teachings;
[0021] FIG. 10 is a flowchart illustrating the hybrid cooling
method according to the present teachings; and
[0022] FIG. 11 is a schematic representation of a cooling module
according to the present teachings.
DETAILED DESCRIPTION
[0023] Example embodiments are provided so that this disclosure
will be thorough, and will fully convey the scope to those who are
skilled in the art. Numerous specific details are set forth such as
examples of specific components, devices, and methods, to provide a
thorough understanding of embodiments of the present disclosure. It
will be apparent to those skilled in the art that specific details
need not be employed, that example embodiments may be embodied in
many different forms and that neither should be construed to limit
the scope of the disclosure. In some example embodiments,
well-known processes, well-known device structures, and well-known
technologies are not described in detail.
[0024] The terminology used herein is for the purpose of describing
particular example embodiments only and is not intended to be
limiting. As used herein, the singular forms "a," "an," and "the"
may be intended to include the plural forms as well, unless the
context clearly indicates otherwise. The terms "comprises,"
"comprising," "including," and "having," are inclusive and
therefore specify the presence of stated features, integers, steps,
operations, elements, and/or components, but do not preclude the
presence or addition of one or more other features, integers,
steps, operations, elements, components, and/or groups thereof. The
method steps, processes, and operations described herein are not to
be construed as necessarily requiring their performance in the
particular order discussed or illustrated, unless specifically
identified as an order of performance. It is also to be understood
that additional or alternative steps may be employed.
[0025] When an element or layer is referred to as being "on,"
"engaged to," "connected to," or "coupled to" another element or
layer, it may be directly on, engaged, connected or coupled to the
other element or layer, or intervening elements or layers may be
present. In contrast, when an element is referred to as being
"directly on," "directly engaged to," "directly connected to," or
"directly coupled to" another element or layer, there may be no
intervening elements or layers present. Other words used to
describe the relationship between elements should be interpreted in
a like fashion (e.g., "between" versus "directly between,"
"adjacent" versus "directly adjacent," etc.). As used herein, the
term "and/or" includes any and all combinations of one or more of
the associated listed items.
[0026] Although the terms first, second, third, etc. may be used
herein to describe various elements, components, regions, layers
and/or sections, these elements, components, regions, layers and/or
sections should not be limited by these terms. These terms may be
only used to distinguish one element, component, region, layer or
section from another region, layer or section. Terms such as
"first," "second," and other numerical terms when used herein do
not imply a sequence or order unless clearly indicated by the
context. Thus, a first element, component, region, layer or section
discussed below could be termed a second element, component,
region, layer or section without departing from the teachings of
the example embodiments.
[0027] Spatially relative terms, such as "inner," "outer,"
"beneath," "below," "lower," "above," "upper," and the like, may be
used herein for ease of description to describe one element or
feature's relationship to another element(s) or feature(s) as
illustrated in the figures. Spatially relative terms may be
intended to encompass different orientations of the device in use
or operation in addition to the orientation depicted in the
figures. For example, if the device in the figures is turned over,
elements described as "below" or "beneath" other elements or
features would then be oriented "above" the other elements or
features. Thus, the example term "below" can encompass both an
orientation of above and below. The device may be otherwise
oriented (rotated 90 degrees or at other orientations) and the
spatially relative descriptors used herein interpreted
accordingly.
[0028] The following description is merely exemplary in nature and
is not intended to limit the present teachings, application, or
uses. It should be understood that throughout the drawings,
corresponding reference numerals indicate like or corresponding
parts and features (e.g., 20, 120, 220, etc.). As used herein, the
term "module" may refer to an application-specific integrated
circuit (ASIC), an electronic circuit, a processor (shared,
dedicated, or group) and memory that executes one or more software
or firmware programs, a combinational logic circuit, or other
suitable components that provide the described functionality.
[0029] An exemplary condensing unit 20 utilizing the cooling
techniques of the present teachings is shown in FIG. 1. Condensing
unit 20 is shown in a partially cut-away perspective view with
various components, connections, and other features removed for
simplicity. Condensing unit 20 includes a condenser 22 that extends
around condensing unit 20. Condenser 22 includes one or more fluid
conduits (not shown) from which a plurality of heat-transferring
fins 60 extend. A fan 26 driven by an electric motor 28 can be
disposed in an interior cavity 30 of condensing unit 20. Fan 26 can
draw an airflow through condenser 22 to remove heat and condense
the working fluid flowing through condenser 22. A compressor 32,
such as a variable-speed compressor, can be disposed in interior
cavity 30. For example, a control module 34 that controls operation
of compressor 32 can be disposed in interior cavity 30 above
compressor 32. Control module 34 can control the operation of
compressor 32 to meet the demands of the heating and
air-conditioning or heat pump system within which condensing unit
20 is used. Control module 34 is also referred to herein as the
drive electronics. Control module 34 is in heat-transferring
relation with a heat sink 36. The airflow induced by fan 26 flows
across heat sink 36 to facilitate removal of heat from control
module 34 via convection.
[0030] Referring now to FIGS. 2 and 3, details of compressor 32 and
control module 34 are shown. Compressor 32 is operable to compress
a working fluid from a suction pressure to a discharge pressure
greater than the suction pressure. Working fluid enters compressor
32 at a suction pressure through suction inlet conduit 38 and is
discharged from compressor 32 at the discharge pressure through
discharge outlet conduit 40. Compressor 32 can take a variety of
forms. For example, compressor 32 can be a variable-speed
compressor that changes speed while in operation, thereby varying
the capacity. Compressor 32 can be a scroll compressor, a
reciprocating compressor, a screw compressor, a rotary compressor,
and the like by way of non-limiting example.
[0031] Control module 34 can include a cover 44 which may be
removed to access the internal components of control module 34, as
shown in FIG. 3. Control module 34 can include one or more circuit
boards 46 and one or more electronic components 48 that enable
control module 34 to perform its functions. It should be
appreciated that the details of control module 34 shown in FIG. 3
are merely exemplary in nature and that control module 34 can
include additional or other components and/or modules, as needed,
to provide the desired functionality.
[0032] A cooling module 50 can be used to command the cooling of
control module 34. Cooling module 50 can be part of control module
34, as shown in FIGS. 3-8, or can be a separate module or
component, as shown in phantom in FIG. 4-8. Cooling module 50 can
ascertain when cooling of control module 34 is needed and command
the appropriate actions to achieve the desired cooling of control
module 34, as described below.
[0033] Heat sink 36 can include a base 54 having a first surface 56
in heat-transferring relation with control module 34. A second
surface 58 of base 54 can include a plurality of fins 60 that
extend outwardly therefrom in heat-transferring relation. Fins 60
facilitate the transferring of heat via convection from heat sink
36 to an airflow induced by fan 26 flowing across fins 60. A fluid
conduit 64 can extend through base 54 to provide additional cooling
for heat sink 36. Fluid conduit 64 allows a working fluid to flow
therethrough in heat-transferring relation with base 54 to remove
heat therefrom. Fluid conduit 64 can extend through base 54 in a
variety of orientations to facilitate heat transfer therebetween.
For example, fluid conduit 64 can extend through base 54 in a
serpentine manner, by way of non-limiting example. A
valve/expansion device 66 (hereinafter valve) is disposed in fluid
conduit 64 and is operable to control the flow of working fluid
therethrough. Valve 66 can be operated by cooling module 50 or
independently of cooling module 50. For example, in some
embodiments cooling module 50 can send signals to valve 66 to open
and close, as needed, to provide the desired cooling for control
module 34, while in some embodiments valve 66 can be responsive to
components independent of cooling module 34, such as a temperature
sensor that causes valve 66 to open and close based on a sensed
temperature. In some embodiments, the temperature sensor can be a
component of cooling module 50, as shown in FIG. 11. A return fluid
conduit 68 communicates with fluid conduit 64 and directs working
fluid exiting base 54 back to the working fluid flowing through the
refrigerant system within which condensing unit 20 is utilized.
[0034] Heat sink 36 is operable to remove heat from control module
34 by air flowing over fins 60 and/or a working fluid flowing
through fluid conduit 64. In this manner, two different methods of
cooling can be realized. The two different cooling methods can be
used independently of one another or can be used in conjunction
with one another, as described below.
[0035] Referring now to FIG. 4, a schematic representation of a
heating and air-conditioning system 70 having a mechanization that
enables working fluid to flow through heat sink 36 according to the
present teachings is shown. In a typical heating and
air-conditioning system, compressor 32 discharges high-pressure,
high-temperature compressed working fluid through discharge conduit
40. The discharged working fluid flows through condenser 22 wherein
the temperature is reduced and the working fluid can condense into
a liquid. The working fluid exits condenser 22 through a conduit 72
and flows through an expansion device 74 which reduces the pressure
of the working fluid. The low-pressure, low-temperature working
fluid flows from expansion device 74 through fluid conduit 76 and
into an evaporator 78. Within evaporator 78, the working fluid can
absorb heat from a fluid flowing along evaporator 78, thereby
increasing the temperature of the working fluid. The working fluid
travels from evaporator 78 back into compressor 32 through suction
conduit 38. The preceding explanation is a description of a typical
vapor-compression cycle utilized in heating and air-conditioning
systems. Thus, it should be appreciated that changes in the
operation can be implemented without deviating from the present
teachings.
[0036] In the mechanization shown in FIG. 4, fluid conduit 64
communicates with conduit 72 to allow condensed working fluid to be
expanded by valve 66 and flow through base 54 and remove heat from
control module 34. Valve 66 can be selectively operated to allow
working fluid in conduit 64 to flow through base 54. The working
fluid flowing through valve 66 will be expanded wherein the
pressure is lowered across valve 66. As a result, a
reduced-pressure, low-temperature working fluid (either gas or
liquid, or both) can flow through base 54 in heat-transferring
relation with control module 34. The working fluid can thereby
convectively absorb heat from base 54 and control module 34. The
working fluid exiting base 54 flows through fluid conduit 68 and is
supplied to suction conduit 38 for entering the suction side of
compressor 32.
[0037] A temperature sensor 82 can be coupled to heat sink 36, such
as to base 54, to provide a signal to cooling module 50 that is
indicative of the temperature of heat sink 36. Cooling module 50
can use this signal to command operation of valve 66 to supply
working fluid through base 54 to reduce the temperature thereof. In
some embodiments, a temperature sensor 84 can be connected to
control module 34 to provide a signal to cooling module 50 that is
indicative of a temperature of control module 34. Cooling module 50
can then command operation of valve 66 based on the signal to allow
working fluid to flow through base 54 and reduce the temperature of
control module 34. In some embodiments, cooling module 50 can
command operation of valve 66 based on the operating conditions of
compressor 32. For example, when compressor 32 is in a low load
operating state, cooling module 50 can maintain valve 66 closed as
sufficient cooling can be achieved through the airflow over fins
60. When operation of compressor 32 is increased, cooling module 50
can command valve 66 to open to thereby allow working fluid to flow
through base 54 and reduce the temperature of control module 34.
The changing operation of compressor 32 can be based on the ambient
conditions, by way of non-limiting example. Thus, in the
mechanization shown in FIG. 4, valve 66 can be opened and closed
based on the temperature of heat sink 36, the temperature of
control module 34, the operating conditions of compressor 32,
and/or the ambient conditions. As shown in FIG. 4, cooling module
50 can be integral with control module 34 or a separate module, as
shown in phantom.
[0038] Air cooling of control module 34 can be provided by fan 26
of condensing unit 20 inducing an airflow across fins 60 and heat
sink 36. Optionally, an airflow across fins 60 and heat sink 36 can
be provided by a separate fan 86 which is independent of condenser
fan 26. Fan 86 is shown in phantom in FIG. 4 to indicate that fan
86 is optional. Fan 86 can be operated independently from fan 26 of
condensing unit 20. Fan 86 can communicate with cooling module 50
and receive signals from cooling module 50 to command operation. In
this manner, cooling module 50 can command independent operation of
fan 86 to provide an airflow across fins 60 and heat sink 36. Thus,
an independent fan 86 can be commanded to induce an airflow over
fins 60 and heat sink 36 to provide air cooling of control module
34. It should be appreciated that in some embodiments both fan 26
and independent fan 86, when present, can be operated
simultaneously to induce airflow over fins 60 and heat sink 36.
Some embodiments (e.g., geothermal units) may include fan 86 and
may not include fan 26.
[0039] Referring now to FIGS. 5 and 6, a heating and
air-conditioning system 170 having another mechanization that
enables the cooling of the heat sink 36 with the working fluid is
shown. Heating and air-conditioning system 170 is similar to
heating and air-conditioning system 70 discussed above. Therefore,
only the differences associated with the mechanization for
providing working fluid through base 54 of heat sink 36 is
discussed.
[0040] In this mechanization, fluid conduit 164 receives expanded
working fluid from fluid conduit 176 downstream of expansion device
74. A thermal valve 190 is disposed in fluid conduit 176 and
coupled to fluid conduit 164. Thermal valve 190 is operable to
allow all of the working fluid to either flow through fluid conduit
176, bypassing fluid conduit 164 and heat sink 36, or to flow
through fluid conduit 164, heat sink 36, and fluid conduit 168 and
rejoin fluid conduit 176 in a downstream location prior to
evaporator 78.
[0041] Valve 190 can direct the flow through fluid conduit 164
based on a temperature of the working fluid entering valve 190.
That is, valve 190 can be a temperature-sensing valve that, upon
detecting a temperature above a predetermined value, directs all of
the flow through heat sink 36 to provide cooling for control module
34. For example, as shown in FIG. 5, fluid conduits 164 and 168 are
indicated in phantom, while fluid conduit 176 is entirely in solid.
In this situation, all of the working fluid flows through fluid
conduit 176 and does not flow through fluid conduits 164, 168 or
heat sink 36. This operation corresponds to operation of control
module 34 without being cooled by the working fluid. As shown in
FIG. 6, when valve 190 redirects the flow of the working fluid
through fluid conduits 164, 168 (now shown in solid), the working
fluid flows through base 54 of heat sink 36 to provide cooling to
control module 34. The working fluid re-enters fluid conduit 176
after flowing through base 54. As such, a portion 176a of fluid
conduit 176 is shown in phantom, thereby indicating that working
fluid does not flow therethrough. In this manner, valve 190 can
automatically adjust to enable working fluid to cool control module
34, as needed, based upon a temperature of the working fluid
entering valve 190. Additionally, in this mechanization, an
entirety of the expanded working fluid flows through base 54 of
heat sink 36 when working fluid is being used to cool control
module 34. Valve 190 can be a component of cooling module 50, as
shown in phantom in FIG. 5 and shown in solid in FIG. 11.
[0042] Referring now to FIGS. 7 and 8, a heating and
air-conditioning system 270 having another mechanization that
enables the cooling of heat sink 36 with the working fluid is
shown. Heating and air-conditioning system 270 is a heat pump
system that is similar to heating and air-conditioning system 70
discussed above. Therefore, only the differences associated with
the mechanization are discussed.
[0043] In this mechanization, heating and air-conditioning system
270 is in the form of a heat pump system and includes an outdoor
heat exchanger 222, an indoor heat exchanger 278, first and second
expansion devices 274a, 274b, and associated bypass conduits 272a,
272b with respective check valves 287a, 287b therein, and a
reversing valve 288. Reversing valve 288 communicates with both
suction conduit 238 and discharge conduit 240 to reverse the flow
through heating and air-conditioning system 270 to switch between a
cooling mode, as shown in FIG. 7, and a heating mode, as shown in
FIG. 8. An outdoor conduit 289 extends between reversing valve 288
and outdoor heat exchanger 222. An indoor conduit 291 extends
between reversing valve 288 and indoor heat exchanger 278.
[0044] In a first position of reversing valve 288, discharge
conduit 240 communicates with outdoor conduit 289 while suction
conduit 238 communicates with indoor conduit 291, as shown in FIG.
7. In a second position of reversing valve 288, discharge conduit
240 communicates with indoor conduit 291 while suction conduit 238
communicates with outdoor conduit 289, as shown in FIG. 8. The
movement of reversing valve 288 between the first and second
positions changes the operation of heating and air-conditioning
system 270 from a cooling mode, as shown in FIG. 7, to a heating
mode, as shown in FIG. 8. Movement of reversing valve 288 can be
based on commands from control module 34, a thermostat (not shown)
or a system controller (not shown).
[0045] Referring now to FIG. 7, when heating and air-conditioning
system 270 is in the cooling mode, reversing valve 288 is in the
first position. In the first position, discharge conduit 240
communicates with outdoor conduit 289 to direct compressed working
fluid to outdoor heat exchanger 222. In outdoor heat exchanger 222,
the temperature of the working fluid is reduced and the working
fluid can condense into a liquid. The working fluid exits outdoor
heat exchanger 222 through conduit 272. In the cooling mode,
expansion device 274a is closed and, as a result, working fluid
flowing through conduit 272 flows through bypass conduit 272a and
through check valve 287a. The working fluid may not experience any
significant change in its state or properties when flowing through
bypass conduit 272a and check valve 287a. After flowing through
bypass conduit 272a, the working fluid re-enters conduit 272 and
flows through expansion device 274b, which is active and reduces
the pressure of the working fluid. The low-pressure,
low-temperature working fluid flows from expansion device 274b into
indoor heat exchanger 278 wherein the working fluid can absorb heat
from a fluid flowing along indoor heat exchanger 278, thereby
increasing the temperature of the working fluid. The working fluid
is prevented from bypassing expansion device 274b through bypass
conduit 272b due to the presence of check valve 287b and the
pressure difference of the working fluid on either side thereof.
Working fluid travels from indoor heat exchanger 278 to reversing
valve 288 through conduit 291 and on into compressor 32 through
suction conduit 238.
[0046] Referring now to FIG. 8, operation of heating and
air-conditioning system 270 in the heating mode is shown. In the
heating mode, reversing valve 288 is in the second position such
that discharge conduit 240 communicates with indoor conduit 291 and
suction conduit 238 communicates with outdoor conduit 289. The
discharged working fluid flows through discharge conduit 240,
through reversing valve 288, and into indoor heat exchanger 278
through indoor conduit 291. In indoor heat exchanger 278, the
temperature of the working fluid is reduced as heat is transferred
from the working fluid to a fluid flowing along indoor heat
exchanger 278, such as an airflow. The working fluid can condense
into a liquid as its temperature is reduced in indoor heat
exchanger 278. The working fluid exits indoor heat exchanger 278
through conduit 272. In the heating mode, expansion device 274b is
closed and the working fluid flows through bypass conduit 272b and
check valve 287b. The working fluid may not experience any
significant change in its state or properties when flowing through
bypass conduit 272b and check valve 287b. The working fluid
continues to flow through conduit 272 and through expansion device
274a, which is active in the heating mode and reduces the pressure
of the working fluid flowing therethrough. The working fluid flows
from expansion device 274a into outdoor heat exchanger 222 through
conduit 272. The working fluid is prevented from flowing through
bypass conduit 272a due to the presence of check valve 287a and the
pressure difference on either side thereof. The low-pressure,
low-temperature working fluid flows from expansion device 274a
through fluid conduit 272 and into outdoor heat exchanger 222.
Within outdoor heat exchanger 222, the working fluid can absorb
heat from a fluid flowing along outdoor heat exchanger 222, thereby
increasing the temperature of the working fluid. The working fluid
travels from outdoor heat exchanger 222 back into compressor 32
through outdoor conduit 289, reversing valve 288, and suction
conduit 238.
[0047] In the mechanizations shown in FIGS. 7 and 8, fluid conduit
64 communicates with conduit 272 between expansion devices 274a,
274b. This positioning of fluid conduit 64 allows condensed working
fluid to flow into fluid conduit 64 and be expanded by valve 66 and
flow through base 54 and remove heat from control module 34, as
described above with reference to the mechanization shown in FIG.
4. When in the cooling mode, the working fluid in communication
with fluid conduit 64 is in a condensed non-expanded state due to
expansion device 274a being closed while expansion device 274b is
active. When in the heating mode, the working fluid in
communication with fluid conduit 64 is again in a condensed
non-expanded state due to expansion device 274b being closed while
expansion device 274a is active. Thus, the same type of cooling can
be provided for control module 34, as described above with
reference to the mechanization shown in FIG. 4, regardless of
heating and air-conditioning system 270 being operated in the
cooling mode or heating mode.
[0048] According to the present teachings, control module 34 can be
cooled by airflow induced by fan 26, fan 86 (when present), and by
working fluid flowing through base 54 of heat sink 36. Typically,
control module 34 will be air cooled by air flowing across fins 60
of heat sink 36. When the air cooling is insufficient to maintain
control module 34 below a predetermined temperature or within a
predetermined temperature-operating range, the cooling can be
supplemented by providing working fluid to base 54 to provide
additional cooling for control module 34. The conditions under
which additional cooling is provided by the working fluid can vary
based upon the needs of control module 34 and the desired operation
of compressor 32 and the system within which compressor 32 is
utilized. For example, the use of air cooling and working fluid
cooling can be dictated by the current compressor 32 operating
condition within an operating envelope 92, such as that shown in
graph 93 of FIG. 9. In graph 93, the saturated evaporator
temperature is shown along the horizontal axis while the saturated
condenser temperature is shown along the vertical axis. A line 95
extends between the horizontal and vertical axes. The area below
line 95, above the vertical axis, and to the left of the horizontal
axis represents the operating envelope 92 within which compressor
32 may operate.
[0049] Within operating envelope 92, control module 34 can be
cooled by air cooling and, in some areas, supplemented with
additional cooling provided by the working fluid. A transition line
96 can divide the operating envelope into a first area 97, wherein
control module 34 is cooled solely by air cooling, and a second
area 98, wherein the cooling of control module 34 is supplemented
with additional cooling provided by working fluid flowing through
heat sink 36. Second area 98 is indicated in cross-hatching in FIG.
9. The location and shape of transition line 96 can vary based upon
the desired operation of compressor 32, the operational-temperature
range of control module 34 and/or the desired operation of the
system within which condensing unit 20 is operating. For example,
in some embodiments, the transition line 96 can be based upon a
condenser temperature of 140.degree. F., as shown in FIG. 9. When
this is the case, the working fluid can be supplied to base 54 of
heat sink 36 whenever the condenser temperature is 140.degree. F.
or greater. When the temperature drops below 140.degree. F., the
working fluid flow through base 54 is ceased and cooling can be
provided entirely by air cooling. In some embodiments (e.g., a
geothermal unit), the operating envelope 92 may be than described
above. For example, the transition line 96 may be at a temperature
lower than 140.degree. F. In such embodiments, independent fan 86
may be used to assist in cooling heat sink 36.
[0050] The use of the working fluid to provide additional cooling
to control module 34 adds an efficiency loss to the system within
which compressor 32 is operating. To reduce the efficiency loss, in
some embodiments the working fluid can be supplied to base 54 of
heat sink 36 only in situations requiring the additional cooling.
Additionally, in some embodiments the use of the working fluid can
be limited to ranges that do not affect the efficiency rating of
compressor 32 and/or the system within which compressor 32 is
utilized. For example, the efficiency rating of compressor 32
and/or the system within which it is utilized can be limited to
specific operating points, such as points 99a, 99b shown in FIG. 9.
These rating points can be industry-derived standards for rating
the efficiencies of the compressor and/or heating and
air-conditioning systems. The use of supplemental cooling provided
by directing working fluid through base 54 of heat sink 36 can
affect the efficiency. Therefore, the supplemental cooling provided
by the working fluid can be limited to areas in operating envelope
92 within which compressor rating points 99a, 99b do not occur. For
example, as shown in FIG. 9, both rating points 99a, 99b are in
first area 97, wherein the entire cooling of control module 34 is
provided by airflow across fins 60. Thus, by limiting the use of
working fluid to provide cooling for control module 34 to areas
within which the compressor rating points do not exist, such as in
second area 98, the use of the working fluid to cool control module
34 does not affect the system rating. Additionally, the use of
working fluid to cool control module 34 can allow control module 34
to operate at a lower temperature, thereby possibly allowing the
use of less-expensive components for control module 34.
[0051] It should be appreciated that compressor operating envelope
92 is merely exemplary in nature and just one possible arrangement
for dividing operating envelope 92 into first and second areas 97,
98 within which different cooling methods, according to the present
teachings, are used is illustrated. Other operating envelopes
having differing transition lines and differing first and second
areas 97, 98 can be utilized, as desired, to achieve a desired
cooling for control module 34.
[0052] Referring now to FIG. 10, a method of implementing the
cooling of a control module 34, according to the present teachings,
is shown. The method begins with the initiating of compressor 32
operation, as indicated in block 200. With the initial startup of
the compressor 32, control module 34 is air cooled, as indicated in
block 202. This can be accomplished by fan 26 and/or fan 86 (when
present) inducing airflow across fins 60 of heat sink 36.
[0053] While control module 34 is being air cooled, control
monitors the status, as indicated in block 204. Cooling module 50
can monitor the status. The types of information monitored can
include the temperature of control module 34, the temperature of
heat sink 36, the demand placed on compressor 32, and/or
environmental conditions, by way of non-limiting example. In some
embodiments, the temperature of the condensed working fluid
downstream of expansion device 74 is monitored, such as with valve
190 in the configuration shown in FIGS. 5 and 6.
[0054] A determination is made if supplemental cooling is needed,
as indicated in block 206. If supplemental cooling is not needed,
control moves to block 208 and monitors the status. If supplemental
cooling is needed, control module 34 is cooled with working fluid,
as indicated in block 210. Specifically, in the configurations
shown in FIGS. 4, 7, and 8, cooling module 50 commands valve 66 to
open, thereby allowing working fluid to flow through fluid conduit
64 and base 54 of heat sink 36 to remove heat from control module
34. In the case of the configuration shown in FIGS. 5 and 6, valve
190 can automatically open upon sensing a temperature of the
working fluid flowing thereto above a predetermined temperature.
The opening of control valve 190 thereby directs the working fluid
through fluid conduit 164 and base 54 of heat sink 36 to remove
heat from control module 34.
[0055] While control module 34 is being cooled with working fluid,
the status is monitored by cooling module 50, as indicated in block
208. In block 212, a determination of the need for supplemental
cooling is ascertained. The determination of whether supplemental
cooling is needed can be done by cooling module 50 and can be based
on the same considerations discussed above with reference to block
206. If supplemental cooling is needed, control returns to block
210 and either initiates cooling of control module 34 with working
fluid, if not already occurring, or continues to cool control
module 34 with working fluid, if already occurring. If supplemental
cooling is not needed, flow of working fluid to base 54 of heat
sink 36 is stopped, as indicated in block 213. In the
configurations shown in FIGS. 4, 7, and 8, this can be accomplished
by cooling module 50 commanding valve 66 to close, thereby stopping
flow of working fluid through heat sink 36. In the configuration
shown in FIGS. 5 and 6, this can be accomplished by valve 190
sensing the temperature of the working fluid having dropped below a
predetermined temperature and stopping the flow of working fluid
through heat sink 36.
[0056] With the flow of working fluid to heat sink 36 stopped,
control determines if compressor 32 is still operating, as
indicated in block 214. If compressor 32 is still operating,
control returns to block 202 and continues to air cool control
module 34. If compressor 32 is no longer operating, control moves
to block 216 and the method ends.
[0057] Thus, the method of the present teachings can utilize
air-cooling and/or other fluid-cooling to cool control module 34
and, as needed, supplement the cooling by supplying working fluid
to base 54 of heat sink 36 to provide additional cooling for
control module 34. The conditions under which the cooling of
control module 34 is supplemented with the working fluid can be
selected to achieve a desired operational-temperature of control
module 34 and can be selected to occur during conditions that do
not include the system rating zone. Additionally, the use of the
working fluid to supplement the cooling can occur during high-load
or high-ambient conditions. By limiting the periods of use of the
working fluid to cool control module 34, increased efficiency can
be achieved over that when working fluid is used to continuously
cool control module 34. Additionally, the use of the two stages of
cooling can reduce the quantity of air cooling necessary to
maintain control module 34 in a desired operational-temperature
range. The ability to provide supplemental cooling may allow the
use of components in control module 34 that have a lower cost due
to the reduced required operational-temperature range of the
components.
[0058] While the present teachings have been described with
reference to specific examples, mechanizations, and methods, it
should be appreciated that changes in these configurations,
mechanizations, and methods can be implemented without deviating
from the present teachings. For example, the configuration of
condensing unit 20 can vary from that shown. Additionally, the
mechanizations shown in FIGS. 4-8 can be altered to change the
locations of fluid conduits 64, 164, 68, 168 to provide the desired
interconnections to the heating and air-conditioning system.
Additionally, the temperatures and operating conditions at which
supplemental cooling is provided by the working fluid can vary from
that shown above. Accordingly, such variations and changes are to
be regarded as being within the spirit and scope of the present
teachings.
* * * * *