U.S. patent application number 16/747810 was filed with the patent office on 2021-07-22 for system and method for lowering humidity within a washing machine appliance.
The applicant listed for this patent is Haier US Appliance Solutions, Inc.. Invention is credited to Rushikesh Salvi, Aaron Lee Welch.
Application Number | 20210222339 16/747810 |
Document ID | / |
Family ID | 1000004611454 |
Filed Date | 2021-07-22 |
United States Patent
Application |
20210222339 |
Kind Code |
A1 |
Salvi; Rushikesh ; et
al. |
July 22, 2021 |
SYSTEM AND METHOD FOR LOWERING HUMIDITY WITHIN A WASHING MACHINE
APPLIANCE
Abstract
A washing machine appliance includes a wash tub defining a wash
chamber and an intake and exhaust duct that are fluidly coupled to
the wash chamber. A fan is operably coupled to one of these ducts
for urging a flow of air through the wash chamber. A controller is
configured for determining that a wash cycle has finished and
operating the fan according to a periodic fan schedule, the
periodic fan schedule comprising an ON time and an OFF time of the
fan, to urge the flow of air through the wash chamber and out the
exhaust duct to lower a humidity within the wash chamber and the
gasket, e.g., to reduce mold and mildew growth.
Inventors: |
Salvi; Rushikesh;
(Louisville, KY) ; Welch; Aaron Lee; (Louisville,
KY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Haier US Appliance Solutions, Inc. |
Wilmington |
DE |
US |
|
|
Family ID: |
1000004611454 |
Appl. No.: |
16/747810 |
Filed: |
January 21, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
D06F 2105/24 20200201;
D06F 2105/30 20200201; D06F 29/005 20130101; D06F 2105/12 20200201;
D06F 2105/32 20200201; D06F 33/44 20200201; D06F 33/64 20200201;
D06F 2103/04 20200201; D06F 33/36 20200201 |
International
Class: |
D06F 33/64 20060101
D06F033/64; D06F 33/36 20060101 D06F033/36; D06F 33/44 20060101
D06F033/44; D06F 29/00 20060101 D06F029/00 |
Claims
1. A washing machine appliance comprising: a wash tub positioned
within a cabinet and defining a wash chamber; a wash basket
rotatably mounted within the wash tub and being configured for
receiving of a load of articles for washing; one or more ducts
providing fluid communication between an ambient environment and
the wash chamber; a fan operably coupled to the one or more ducts
for urging a flow of air through the one or more ducts and through
the wash chamber; and a controller operably coupled to the fan, the
controller being configured for: determining that a wash cycle has
finished; and selectively operating the fan according to a periodic
fan schedule, the periodic fan schedule comprising an ON time and
an OFF time of the fan.
2. The washing machine appliance of claim 1, wherein the ON time
and the OFF time are fixed time intervals.
3. The washing machine appliance of claim 1, wherein the periodic
fan schedule comprises 5 minutes of fan operation every 30
minutes.
4. The washing machine appliance of claim 1, wherein selectively
operating the fan comprises: repeating the periodic fan schedule
until a total drying time has lapsed, the total drying time being
measured from the end of the wash cycle.
5. The washing machine appliance of claim 4, wherein the total
drying time is between about 6 and 10 hours.
6. The washing machine appliance of claim 4, wherein the total
drying time is about 8 hours.
7. The washing machine appliance of claim 1, wherein the one or
more ducts comprises: an intake duct providing fluid communication
between the ambient environment and the wash chamber for providing
the flow of air into the wash chamber; and an exhaust duct
providing fluid communication between the wash chamber and the
ambient environment for discharging the flow of air from the wash
chamber.
8. The washing machine appliance of claim 7, wherein the fan is
mounted in the exhaust duct at a rear panel of the washing machine
appliance.
9. The washing machine appliance of claim 1, further comprising: a
vent door operably coupled to one of the one or more ducts for
regulating the flow of air, wherein the controller is further
configured for: opening the vent door when the fan is
operating.
10. The washing machine appliance of claim 1, wherein the
controller is further configured for: determining whether a load is
in the wash chamber; and selectively operating the fan according to
the periodic fan schedule only if there is no load in the wash
chamber.
11. The washing machine appliance of claim 1, further comprises: a
vent button, wherein the periodic fan schedule is initiated only
when the vent button has been pressed after a wash cycle.
12. The washing machine appliance of claim 1, wherein the fan is a
single speed fan.
13. A method of lowering a humidity within a washing machine
appliance, the washing machine appliance comprising a wash basket
rotatably mounted within a wash tub, one or more ducts providing
fluid communication between an ambient environment and the wash
chamber, and a fan operably coupled to the one or more ducts, the
method comprising: determining that a wash cycle has finished; and
selectively operating the fan according to a periodic fan schedule
to urge a flow of air through the wash chamber, the periodic fan
schedule comprising an ON time and an OFF time of the fan.
14. The method of claim 13, wherein the ON time and the OFF time
are fixed time intervals.
15. The method of claim 13, wherein the periodic fan schedule
comprises 5 minutes of fan operation every 30 minutes.
16. The method of claim 13, wherein selectively operating the fan
comprises: repeating the periodic fan schedule until a total drying
time has lapsed, the total drying time being measured from the end
of the wash cycle.
17. The method of claim 16, wherein the total drying time is about
8 hours.
18. The method of claim 13, wherein the washing machine appliance
comprises a vent door operably coupled to at least one of the one
or more ducts for regulating the flow of air, the method further
comprising: opening the vent door when the fan is operating.
19. The method of claim 13, further comprising: determining whether
a load is in the wash chamber; and selectively operating the fan
according to the periodic fan schedule only if there is no load in
the wash chamber.
20. The method of claim 13, wherein the washing machine further
comprises a vent button, the method further comprising: selectively
operating the fan according to the periodic fan schedule only when
the vent button has been pressed after a wash cycle.
Description
FIELD OF THE INVENTION
[0001] The present subject matter relates generally to washing
machine appliances, or more specifically, to systems and methods
for reducing humidity and moisture within a washing machine
appliance.
BACKGROUND OF THE INVENTION
[0002] Washing machine appliances generally include a tub for
containing water or wash fluid, e.g., water and detergent, bleach,
and/or other wash additives. A basket is rotatably mounted within
the tub and defines a wash chamber for receipt of articles for
washing. During normal operation of such washing machine
appliances, the wash fluid is directed into the tub and onto
articles within the wash chamber of the basket. The basket or an
agitation element can rotate at various speeds to agitate articles
within the wash chamber, to wring wash fluid from articles within
the wash chamber, etc. During a spin or drain cycle, a drain pump
assembly may operate to discharge water from within sump.
[0003] Notably, when the wash or rinse cycle is completed, excess
wash fluid commonly collects in a bottom of the tub, within the
door gasket, etc. Because the wash tub is partially or
substantially sealed, this wash fluid remains in the tub until the
next wash or rinse cycle and the humidity remains relatively
constant between cycles. Such collected wash fluid, excessive
humidity, and moisture may result in mold, mildew, or foul smells.
Notably, conventional washing machine appliances have no way to
reduce such moisture collection or mitigate that effects of such
moisture. For example, users typically must leave the door open
after every cycle, which can be burdensome and can be relatively
ineffective at evaporating collected wash fluid.
[0004] Accordingly, a washing machine appliance having improved
features for reducing moisture and humidity would be desirable.
More specifically, a washing machine appliance with an improved
system and method for reducing the humidity and minimizing mold and
mildew in the wash tub would be particularly beneficial.
BRIEF DESCRIPTION OF THE INVENTION
[0005] Advantages of the invention will be set forth in part in the
following description, or may be apparent from the description, or
may be learned through practice of the invention.
[0006] In accordance with one exemplary embodiment of the present
disclosure, a washing machine appliance is provided, including a
wash tub positioned within a cabinet and defining a wash chamber, a
wash basket rotatably mounted within the wash tub and being
configured for receiving of a load of articles for washing, and one
or more ducts providing fluid communication between an ambient
environment and the wash chamber. A fan is operably coupled to the
one or more ducts for urging a flow of air through the one or more
ducts and through the wash chamber and a controller is operably
coupled to the fan and being configured determining that a wash
cycle has finished and selectively operating the fan according to a
periodic fan schedule, the periodic fan schedule including an ON
time and an OFF time of the fan.
[0007] In accordance with another exemplary embodiment of the
present disclosure, a method of lowering a humidity within a
washing machine appliance is provided. The washing machine
appliance includes a wash basket rotatably mounted within a wash
tub, one or more ducts providing fluid communication between an
ambient environment and the wash chamber, and a fan operably
coupled to the one or more ducts. The method includes determining
that a wash cycle has finished and selectively operating the fan
according to a periodic fan schedule to urge a flow of air through
the wash chamber, the periodic fan schedule comprising an ON time
and an OFF time of the fan.
[0008] These and other features, aspects and advantages of the
present invention will become better understood with reference to
the following description and appended claims. The accompanying
drawings, which are incorporated in and constitute a part of this
specification, illustrate embodiments of the invention and,
together with the description, serve to explain the principles of
the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] A full and enabling disclosure of the present invention,
including the best mode thereof, directed to one of ordinary skill
in the art, is set forth in the specification, which makes
reference to the appended figures.
[0010] FIG. 1 provides a perspective view of an exemplary washing
machine appliance according to an exemplary embodiment of the
present subject matter.
[0011] FIG. 2 provides a side cross-sectional view of the exemplary
washing machine appliance of FIG. 1.
[0012] FIG. 3 provides a side cross-sectional view of the exemplary
washing machine appliance of FIG. 1.
[0013] FIG. 4 is a perspective view of a damper assembly for use
with the exemplary washing machine appliance of FIG. 3 according to
an exemplary embodiment of the present subject matter.
[0014] FIG. 5 is a cross sectional view of the exemplary damper
assembly of FIG. 4 according to an exemplary embodiment of the
present subject matter.
[0015] FIG. 6 is a cross sectional view of the exemplary damper
assembly of FIG. 4 according to an exemplary embodiment of the
present subject matter.
[0016] FIG. 7 illustrates a method for lowering a humidity in a
washing machine appliance in accordance with one embodiment of the
present disclosure.
[0017] FIG. 8 provides an exemplary plot of the wash chamber and/or
gasket humidity over time while the exemplary method of FIG. 7 is
being used to reduce humidity in the washing machine appliance.
[0018] Repeat use of reference characters in the present
specification and drawings is intended to represent the same or
analogous features or elements of the present invention.
DETAILED DESCRIPTION
[0019] Reference now will be made in detail to embodiments of the
invention, one or more examples of which are illustrated in the
drawings. Each example is provided by way of explanation of the
invention, not limitation of the invention. In fact, it will be
apparent to those skilled in the art that various modifications and
variations can be made in the present invention without departing
from the scope or spirit of the invention. For instance, features
illustrated or described as part of one embodiment can be used with
another embodiment to yield a still further embodiment. Thus, it is
intended that the present invention covers such modifications and
variations as come within the scope of the appended claims and
their equivalents.
[0020] Referring now to the figures, FIG. 1 is a perspective view
of an exemplary horizontal axis washing machine appliance 100 and
FIG. 2 is a side cross-sectional view of washing machine appliance
100. As illustrated, washing machine appliance 100 generally
defines a vertical direction V, a lateral direction L, and a
transverse direction T, each of which is mutually perpendicular,
such that an orthogonal coordinate system is generally defined.
Washing machine appliance 100 includes a cabinet 102 that extends
between a top 104 and a bottom 106 along the vertical direction V,
between a left side 108 and a right side 110 along the lateral
direction, and between a front 112 and a rear 114 along the
transverse direction T.
[0021] Referring to FIG. 2, a wash basket 120 is rotatably mounted
within cabinet 102 such that it is rotatable about an axis of
rotation A. A motor 122, e.g., such as a pancake motor, is in
mechanical communication with wash basket 120 to selectively rotate
wash basket 120 (e.g., during an agitation or a rinse cycle of
washing machine appliance 100). Wash basket 120 is received within
a wash tub 124 and defines a wash chamber 126 that is configured
for receipt of articles for washing. The wash tub 124 holds wash
and rinse fluids for agitation in wash basket 120 within wash tub
124. As used herein, "wash fluid" may refer to water, detergent,
fabric softener, bleach, or any other suitable wash additive or
combination thereof. Indeed, for simplicity of discussion, these
terms may all be used interchangeably herein without limiting the
present subject matter to any particular "wash fluid."
[0022] Wash basket 120 may define one or more agitator features
that extend into wash chamber 126 to assist in agitation and
cleaning articles disposed within wash chamber 126 during operation
of washing machine appliance 100. For example, as illustrated in
FIG. 2, a plurality of ribs 128 extends from basket 120 into wash
chamber 126. In this manner, for example, ribs 128 may lift
articles disposed in wash basket 120 during rotation of wash basket
120.
[0023] Referring generally to FIGS. 1 and 2, cabinet 102 also
includes a front panel 130 which defines an opening 132 that
permits user access to wash basket 120 of wash tub 124. More
specifically, washing machine appliance 100 includes a door 134
that is positioned over opening 132 and is rotatably mounted to
front panel 130. In this manner, door 134 permits selective access
to opening 132 by being movable between an open position (not
shown) facilitating access to a wash tub 124 and a closed position
(FIG. 1) prohibiting access to wash tub 124.
[0024] A window 136 in door 134 permits viewing of wash basket 120
when door 134 is in the closed position, e.g., during operation of
washing machine appliance 100. Door 134 also includes a handle (not
shown) that, e.g., a user may pull when opening and closing door
134. Further, although door 134 is illustrated as mounted to front
panel 130, it should be appreciated that door 134 may be mounted to
another side of cabinet 102 or any other suitable support according
to alternative embodiments.
[0025] Referring again to FIG. 2, wash basket 120 also defines a
plurality of perforations 140 in order to facilitate fluid
communication between an interior of basket 120 and wash tub 124. A
sump 142 is defined by wash tub 124 at a bottom of wash tub 124
along the vertical direction V. Thus, sump 142 is configured for
receipt of and generally collects wash fluid during operation of
washing machine appliance 100. For example, during operation of
washing machine appliance 100, wash fluid may be urged by gravity
from basket 120 to sump 142 through plurality of perforations
140.
[0026] A drain pump assembly 144 is located beneath wash tub 124
and is in fluid communication with sump 142 for periodically
discharging soiled wash fluid from washing machine appliance 100.
Drain pump assembly 144 may generally include a drain pump 146
which is in fluid communication with sump 142 and with an external
drain 148 through a drain hose 150. During a drain cycle, drain
pump 146 urges a flow of wash fluid from sump 142, through drain
hose 150, and to external drain 148. More specifically, drain pump
146 includes a motor (not shown) which is energized during a drain
cycle such that drain pump 146 draws wash fluid from sump 142 and
urges it through drain hose 150 to external drain 148.
[0027] A spout 154 is configured for directing a flow of fluid into
wash tub 124. For example, spout 154 may be in fluid communication
with a water supply 155 (FIG. 2) in order to direct fluid (e.g.,
clean water or wash fluid) into wash tub 124. Spout 154 may also be
in fluid communication with the sump 142. For example, pump
assembly 144 may direct wash fluid disposed in sump 142 to spout
154 in order to circulate wash fluid in wash tub 124.
[0028] As illustrated in FIG. 2, a detergent drawer 156 is slidably
mounted within front panel 130. Detergent drawer 156 receives a
wash additive (e.g., detergent, fabric softener, bleach, or any
other suitable liquid or powder) and directs the fluid additive to
wash chamber 124 during operation of washing machine appliance 100.
According to the illustrated embodiment, detergent drawer 156 may
also be fluidly coupled to spout 154 to facilitate the complete and
accurate dispensing of wash additive.
[0029] In addition, a water supply valve or control valve 158 may
provide a flow of water from a water supply source (such as a
municipal water supply 155) into detergent dispenser 156 and into
wash tub 124. In this manner, control valve 158 may generally be
operable to supply water into detergent dispenser 156 to generate a
wash fluid, e.g., for use in a wash cycle, or a flow of fresh
water, e.g., for a rinse cycle. It should be appreciated that
control valve 158 may be positioned at any other suitable location
within cabinet 102. In addition, although control valve 158 is
described herein as regulating the flow of "wash fluid," it should
be appreciated that this term includes, water, detergent, other
additives, or some mixture thereof.
[0030] A control panel 160 including a plurality of input selectors
162 is coupled to front panel 130. Control panel 160 and input
selectors 162 collectively form a user interface input for operator
selection of machine cycles and features. For example, in one
embodiment, a display 164 indicates selected features, a countdown
timer, and/or other items of interest to machine users.
[0031] Operation of washing machine appliance 100 is controlled by
a controller or processing device 166 (FIG. 1) that is operatively
coupled to control panel 160 for user manipulation to select
washing machine cycles and features. In response to user
manipulation of control panel 160, controller 166 operates the
various components of washing machine appliance 100 to execute
selected machine cycles and features.
[0032] Controller 166 may include a memory and microprocessor, such
as a general or special purpose microprocessor operable to execute
programming instructions or micro-control code associated with a
cleaning cycle. The memory may represent random access memory such
as DRAM, or read only memory such as ROM or FLASH. In one
embodiment, the processor executes programming instructions stored
in memory. The memory may be a separate component from the
processor or may be included onboard within the processor.
Alternatively, controller 166 may be constructed without using a
microprocessor, e.g., using a combination of discrete analog and/or
digital logic circuitry (such as switches, amplifiers, integrators,
comparators, flip-flops, AND gates, and the like) to perform
control functionality instead of relying upon software. Control
panel 160 and other components of washing machine appliance 100 may
be in communication with controller 166 via one or more signal
lines or shared communication busses.
[0033] During operation of washing machine appliance 100, laundry
items are loaded into wash basket 120 through opening 132, and
washing operation is initiated through operator manipulation of
input selectors 162. Wash tub 124 is filled with water, detergent,
and/or other fluid additives, e.g., via spout 154 and or detergent
drawer 156. One or more valves (e.g., control valve 158) can be
controlled by washing machine appliance 100 to provide for filling
wash basket 120 to the appropriate level for the amount of articles
being washed and/or rinsed. By way of example for a wash mode, once
wash basket 120 is properly filled with fluid, the contents of wash
basket 120 can be agitated (e.g., with ribs 128) for washing of
laundry items in wash basket 120.
[0034] After the agitation phase of the wash cycle is completed,
wash tub 124 can be drained. Laundry articles can then be rinsed by
again adding fluid to wash tub 124, depending on the particulars of
the cleaning cycle selected by a user. Ribs 128 may again provide
agitation within wash basket 120. One or more spin cycles may also
be used. In particular, a spin cycle may be applied after the wash
cycle and/or after the rinse cycle in order to wring wash fluid
from the articles being washed. During a final spin cycle, basket
120 is rotated at relatively high speeds and drain pump assembly
144 may discharge wash fluid from sump 142. After articles disposed
in wash basket 120 are cleaned, washed, and/or rinsed, the user can
remove the articles from wash basket 120, e.g., by opening door 134
and reaching into wash basket 120 through opening 132.
[0035] While described in the context of a specific embodiment of
horizontal axis washing machine appliance 100, using the teachings
disclosed herein it will be understood that horizontal axis washing
machine appliance 100 is provided by way of example only. Other
washing machine appliances having different configurations,
different appearances, and/or different features may also be
utilized with the present subject matter as well, e.g., vertical
axis washing machine appliances.
[0036] Referring now generally to FIGS. 3 through 6, a washing
machine appliance and a humidity reduction system 170 will be
described according to an exemplary embodiment of the present
subject matter. Due to the similarity between the washing machine
appliance illustrated in FIGS. 3 through 6 and washing machine
appliance 100, like reference numerals may be used to refer to the
same or similar features. As explained briefly above, washing
machine appliance 100 may tend to collect excess liquid or moisture
within particular locations where mold, mildew, and foul smells may
be generated. Aspects of the present subject matter are directed to
features for reducing the humidity and moisture within washing
machine appliance 100, thereby reducing the likelihood of such
moisture related issues.
[0037] Specifically, humidity reduction system 170 may be operably
coupled to a dedicated controller or appliance controller 166 for
selectively reducing humidity within washing machine appliance 100.
In this regard, humidity reduction system 170 includes an intake
duct 172 that provides fluid communication between an ambient
environment 174 and wash chamber 126 for providing a flow of air,
e.g., as indicated by reference numeral 176 in FIG. 3. In addition,
humidity reduction system 170 includes an exhaust duct 178 that
provides fluid communication between wash chamber 126 and ambient
environment 174 for discharging the flow of air 176 from wash
chamber 126. Although one exemplary construction, positioning, and
configuration of humidity reduction system 170 is described herein,
it should be appreciated that variations and modifications may be
made to humidity reduction system 170 while remaining within the
scope of the present subject matter.
[0038] According to the illustrated embodiment, intake duct 172
extends from an intake inlet 190 positioned at front 112 of cabinet
102 to an intake outlet 192. Thus, the flow of air 176 from ambient
environment 174, e.g., from outside of cabinet 102, may be drawn
into intake duct 172 through intake inlet 190. The flow of air 176
may then pass into wash chamber 126 through intake outlet 192.
Specifically, washing machine appliance 100 may include a door
gasket 194 that is positioned between wash tub 124 and door 134,
e.g., to provide a fluid seal therebetween. Notably, door gasket
194 frequently has crevices or creases that tend to collect wash
fluid or retain excess moisture. Thus, according to the illustrated
embodiment, intake outlet 192 is defined on door gasket 194, e.g.,
proximate a top of door gasket 194. Thus, the flow of air 176
passes directly into door gasket 194, circulates through door
gasket 194, and passes into wash chamber 126 before exiting washing
machine appliance 100 through exhaust duct 178. Specifically,
exhaust duct 178 defines an exhaust inlet 196 and an exhaust outlet
198. According to the illustrated embodiment, exhaust inlet 196 is
defined on wash tub 124 and exhaust outlet 198 is defined in a rear
114 of cabinet 102.
[0039] Notably, for reasons described in more detail below, it may
be frequently desirable to stop the flow of air 176 passing through
intake duct 172 and exhaust duct 178 of humidity reduction system
170. Therefore, according to exemplary embodiments of the present
subject matter, humidity reduction system 170 further includes a
vent door 200 or another suitable damper system configured for
selectively restricting or stopping the flow of air 176. In this
regard, as best shown in FIGS. 4 through 6, vent door 200 may be
positioned within a damper housing 202 that is fluidly coupled to,
or forms a part of, intake duct 172. Specifically, vent door 200
may be pivotally mounted at a hinge 204 and may be movable between
a closed position (not shown) in an open position (e.g., as shown
in FIG. 6). According to the illustrated embodiment, vent door 200
is operably coupled to intake duct 172. However, it should be
appreciated that according to alternative embodiments, vent door
200 could be positioned on exhaust duct 178 or at any other
suitable location within humidity reduction system 170.
[0040] As best shown in FIGS. 4 and 5, vent door 200 may be
operably coupled with a vent door actuator 206 for moving vent door
200 between the open position and the closed position. For example,
according to the illustrated embodiment, the door actuator 206 is a
stepper motor 208 that may selectively position vent door 200 and
the fully closed position, the fully open position, or any other
suitable positioning therebetween. According to alternative
embodiments, vent door actuator 206 may be a hydraulic actuator, an
electromagnetic actuator, or any other suitable device for changing
the position of vent door 200. Vent door 200 may further include a
resilient seal 210, e.g., for forming an airtight seal when vent
door 200 is closed.
[0041] As will be described in more detail below, controller 166 of
washing machine appliance 100 may be operably coupled with both
stepper motor 208 of door 200 and with motor 122 for rotating wash
basket 120. Thus, at desired times, controller 166 may implement a
humidity reduction cycle using humidity reduction system 170. For
example, such a cycle may include opening vent door 200 and
selectively rotating wash basket 120 to urge the flow of air 176
through door gasket 194 and wash chamber 126.
[0042] Notably, according to an exemplary embodiment, a humidity
reduction cycle may be performed following every wash or rinse
cycle. According to other embodiments, washing machine appliance
100 may include one or more humidity sensors that detect the
humidity within wash chamber 126 and initiate a humidity reduction
cycle when humidity levels reach or remain at an unsuitable
humidity level. However, according to the illustrated embodiment,
washing machine appliance 100 does not include humidity sensors
(thus resulting in costs and appliance complexity savings).
According to such an embodiment, a humidity reduction cycle may be
performed after every cycle, after a predetermined number of
cycles, after a specific amount of time has passed, or according to
any other suitable schedule.
[0043] In addition, as best illustrated in FIG. 1, washing machine
appliance 100 may further include a vent button 220 that may be
used to control the performance of the humidity reduction cycles.
In this regard, vent button 220 may be operably coupled with
controller 166, and a user may press vent button 220 to cycle
between different humidity reduction schedules. For example,
pressing the vent button 220 may initiate a single humidity
reduction cycle, e.g., an on-demand cycle. Thus, a humidity
reduction cycle might not be performed after every wash cycle
(resulting in energy savings and noise reduction). Instead, for
example, such cycles may be performed on-demand, or vent button 220
may be used to cause a humidity reduction cycle to be performed
every cycle or at a suitable cycle or time-based frequency, or the
user may turn the humidity reduction cycles off altogether.
[0044] Referring now specifically to FIG. 3, humidity reduction
system 170 may further include an air handler 230 that is
positioned within exhaust duct 178, e.g., proximate rear 114 of
cabinet 102. Air handler 230 may be operably coupled with
controller 166 and may be selectively operated to urge the flow of
air 176 through intake duct 172, wash chamber 126, and exhaust duct
178. Although air handler 230 is illustrated as a single axial fan
positioned within exhaust duct 178, it should be appreciated that
humidity reduction system 170 may include any suitable number,
type, position, and configuration of air handling devices while
remaining within the scope of the present subject matter. For
example, it should be appreciated that according to alternative
embodiments, air handler 230 may be positioned within intake duct
172 and may be any other suitable fan type, such as a single speed
or variable speed fan, a tangential fan, a centrifugal fan,
etc.
[0045] Now that the construction of washing machine appliance 100
and the configuration of controller 166 according to exemplary
embodiments have been presented, an exemplary method 300 of
operating a washing machine appliance will be described. Although
the discussion below refers to the exemplary method 300 of
operating washing machine appliance 100, one skilled in the art
will appreciate that the exemplary method 300 is applicable to the
operation of a variety of other washing machine appliances, such as
vertical axis washing machine appliances. In exemplary embodiments,
the various method steps as disclosed herein may be performed by
controller 166 or a separate, dedicated controller.
[0046] Referring now to FIG. 7, method 300 includes, at step 310,
determining that a wash cycle has finished. In this regard, for
example, controller 166 may detect when a wash cycle, a rinse
cycle, and/or spin cycle has ended. Step 320 may include
determining that a vent button has been pressed, or that washing
machine appliance 100 is otherwise intended to perform a humidity
reduction cycle. In this regard, as explained briefly above, a user
may set washing machine appliance 100 to perform a humidity
reduction cycle after every wash cycle, on-demand, after a
predetermined number of cycles, etc. Vent button 230 provide the
means for a user to manipulate the frequency of performance of such
humidity reduction cycles, e.g., for improved moisture reduction or
improved energy savings and noise reduction.
[0047] Notably, it may be desirable to avoid operating a humidity
reduction cycle when clothes or other articles remain within wash
chamber 126. Thus, step 330 may include determining whether a load
is in the wash chamber 126. For example, controller 166 may operate
motor 122 to briefly rotate wash basket 120. Controller 166 may
further be used to detect whether a load is being tumbled as wash
basket 120 rotates, e.g., based on the back EMF of motor 122, based
on vibration or load sensors, etc. According to exemplary
embodiments, if a wash cycle has been finished (e.g., as determined
at step 310), if the vent button has been pressed or wash machine
appliance 100 is instructed to perform a humidity reduction cycle
after every wash cycle (e.g., as determined at step 320), and if
there are no clothes in wash chamber 126 (e.g., as determined at
step 330), controller 166 may initiate a humidity reduction cycle
as explained in further detail with respect to steps 340 through
360.
[0048] The humidity reduction cycle is generally configured for
reducing a humidity or moisture within door gasket 194 and wash
chamber 126, e.g., to prevent the formation of mold, mildew, or
stale smells. As explained above, such a humidity reduction cycle
may be initiated automatically or based on a user input, e.g., such
as via vent button 220.
[0049] Specifically, for example, it may be desirable to ensure
vent door 200 remains in the open position any time air handler 230
is operated. Thus, step 340 includes opening a vent door operably
coupled to one or more ducts (e.g., intake or exhaust duct). After
vent door is open, step 350 includes selectively operating a fan
according to a periodic fan schedule to urge a flow of air through
the wash chamber and the one or more ducts. Specifically, as
described in detail below, the periodic fan schedule includes both
a time when air handler 230 is operating (e.g., referred to herein
as "ON" time) and a time when air handler 230 is not operating or
is stopped (e.g., referred to herein as "OFF" time).
[0050] In addition to operating air handler 230 according to
periodic fan schedule, according to alternative embodiments,
controller 166 may also operate a drive motor to rotate a wash
basket to further facilitate the flow of air within the wash
chamber. In this regard, for example, while air handler 230 is
rotating, controller 166 may operate motor 122 to rotate wash
basket 120 to increase air circulation within wash chamber 126.
However, it should be appreciated that according to alternative
embodiments, wash basket 120 may remain stationary during a
humidity reduction cycle. Notably, when vent door 200 is open and
air handler 230 is operating, the flow of air 176 is urged through
intake duct 172, into door gasket 194 and wash chamber 126, and out
of wash chamber 126 through exhaust duct 178, thereby discharging
air with relatively high humidity.
[0051] As mentioned above, the periodic fan schedule may include
fixed or variable ON times and OFF times. For example, according to
an exemplary embodiment, periodic fan schedule may include
operating fan for 5 minutes out of every 30 minutes (e.g., 5
minutes of ON time followed by 25 minutes of OFF time). By
contrast, according to alternative embodiments, periodic fan
schedule may include operating fan for 10 minutes out of every 30
minutes (e.g., 10 minutes of ON time followed by 20 minutes of OFF
time), operating fan for 15 minutes out of every 30 minutes (e.g.,
15 minutes of ON time followed by 15 minutes of OFF time),
operating fan for 10 minutes out of every 1 hour (e.g., 10 minutes
of ON time followed by 50 minutes of OFF time), or operating fan
according to any other suitable ON/OFF schedule.
[0052] In addition, method 300 may include, at step 360, repeating
the periodic fan schedule until a total drying time has lapsed, the
total drying time being measured from the end of the wash cycle.
Notably, the periodic fan schedule and the total drying time may be
selected by the manufacturer based on empirical data associated
with normal or intended use of washing machine appliance 100. For
example, lab testing may determine a desirable periodic fan
schedule and total drying time for wash chamber 126 and gasket 194
to reach a desirable moisture or humidity threshold. Alternatively,
the periodic fan schedule and total drying time may be set by a
user or determined in any other suitable manner.
[0053] According to exemplary embodiments, total drying time may be
between about 1 and 24 hours, between about 2 and 20 hours, between
about 3 and 18 hours, between about 4 and 14 hours, between about 5
and 12 hours, between about 6 and 10 hours, or about 8 hours. Other
suitable total drying times are possible and within scope of the
present subject matter.
[0054] Referring briefly to FIG. 8, a plot illustrating the average
wash chamber or gasket humidity over a humidity reduction cycle is
illustrated according to an exemplary embodiment. As shown, when
air handler 230 is active (e.g., during ON time of the periodic fan
schedule), air is circulating within wash chamber 126 resulting in
a sharp drop in chamber relative humidity (RH %). However, when air
handler 230 is stopped (e.g., during OFF time of the periodic fan
schedule) the relative humidity quickly rises as wash chamber 126
normalizes and the newly introduced air begins to become humidified
by water remaining within wash chamber 126 and gasket 194.
[0055] Notably, when the humidity reduction cycle reaches eight
hours after the wash cycle has ended (e.g., as identified by the
dotted lines), the relative humidity within wash chamber 126 is
within 5% of the ambient humidity outside of washing machine
appliance 100. It should be appreciated that according to
alternative embodiments, other suitable total drying times may be
used. For example, the total drying time may be selected based on
the time require for a different between the ambient humidity and
the chamber humidity to fall below a predetermined threshold. Other
means for determining the stop time of the humidity reduction cycle
may be used while remaining within scope of the present subject
matter.
[0056] FIG. 7 depicts steps performed in a particular order for
purposes of illustration and discussion. Those of ordinary skill in
the art, using the disclosures provided herein, will understand
that the steps of any of the methods discussed herein can be
adapted, rearranged, expanded, omitted, or modified in various ways
without deviating from the scope of the present disclosure.
Moreover, although aspects of method 300 are explained using
washing machine appliance 100 as an example, it should be
appreciated that these methods may be applied to the operation of
any suitable washing machine appliance.
[0057] The system and method described above for reducing humidity
and moisture within a washing machine appliance provides a
cost-effective and efficient method for reducing excess moisture,
mold growth, mildew, and foul smells within the washing machine
appliance. Specifically, aspects of the present subject matter help
to evaporate water that has accumulated in the gasket quickly in
addition to reducing humidity in the washer after the clothes have
been removed from washer at the end of wash cycle. The evaporation
of water in the gasket prevents mold growth and the development of
fouls odors in the washing machine. Specifically, a fan is
installed on the back panel of the washer and is operated according
to a repeated periodic cycle after the wash cycle is completed and
the washed load has been removed.
[0058] According to exemplary embodiments, spinning the fan induces
forced convection within the wash chamber, while fresh air is
introduced through front vent of the unit and exhaled out through
rear panel. However, the rate of evaporation may be limited by the
difference between the saturated water vapor density at the surface
temperature of the water and the ambient water vapor density (e.g.,
the washer water vapor density). Hence, the effective water
evaporation by forced convection from a continuously operating fan
may be limited. Therefore, aspects of the present subject matter
are directed to a periodic, ON/OFF fan cycle, which includes
cycling the fan ON and OFF according to fixed time schedule
repeatedly for a total drying time, such as eight hours. The fan
spin in a periodic cycle is an effective way to reduce humidity for
several reasons. For example, it forces the water evaporation by
forced convection. In addition, when the evaporation limit is
reached, the fan is stopped, thereby allowing the air to be
exchanged with outside environment thus preventing the inhibition
of water evaporation rate. Thus, according to exemplary
embodiments, the time the fan is not spinning is as important as
the time the fan is spinning.
[0059] This written description uses examples to disclose the
invention, including the best mode, and also to enable any person
skilled in the art to practice the invention, including making and
using any devices or systems and performing any incorporated
methods. The patentable scope of the invention is defined by the
claims, and may include other examples that occur to those skilled
in the art. Such other examples are intended to be within the scope
of the claims if they include structural elements that do not
differ from the literal language of the claims, or if they include
equivalent structural elements with insubstantial differences from
the literal languages of the claims.
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