Patent Publication Number: US-2023160122-A1

Title: Washing machine ventilation structure

Description:
FIELD OF THE INVENTION 
     The present subject matter relates generally to washing machine appliances and, more particularly, to washing machine appliances having one or more ventilation features. 
     BACKGROUND OF THE INVENTION 
     Washing machine appliances generally include a wash tub for containing water or wash fluid (e.g., water, detergent, bleach, or other wash additives). A wash basket is rotatably mounted within the wash 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 wash tub and onto articles within the wash chamber of the wash basket. The wash basket or an agitation element can rotate at various speeds to agitate articles within the wash chamber and to wring wash fluid from articles within the wash chamber. 
     Some existing washing machine appliances, such as horizontal axis washing machines or front load washing machines, may be provided with one or more ventilation features. Such features may allow a washing machine appliance to exchange air between the wash tub and the ambient environment. The exchange of air may be necessary to prevent moisture from accumulating within the wash tub. For example, if the wash tub is not ventilated, moist, stagnant air may form within the washing machine. Furthermore, ventilation may be required for pressure equalization during wash and rinse cycles of washing machines. 
     Challenges exist in ventilation features, however. Ventilation features are a potential pathway for cleaning fluids to exit the wash tub. For example, to wring wash or rinse fluid from articles in the wash chamber, the wash basket may rotate at a high speed to send fluid out of the wash basket through perforations and into an annulus between the wash basket and the wash tub. As wash fluid is sent out of the wash basket, sometimes at relatively high speed and in various directions, it may be directed out of ventilation features. Wash fluid would then be outside the wash tub, undesirably wetting other components of the washing machine and in extreme cases, depositing fluid outside of the appliance. 
     Accordingly, a washing machine appliance having the ability to remove moisture by use of ventilation features while also preventing wash liquids from exiting the wash tub would be useful. A ventilation feature that allowed air to exit the wash tub while deterring liquids from exiting the wash tub at the same time would be beneficial. 
     BRIEF DESCRIPTION OF THE INVENTION 
     Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention. 
     In one exemplary embodiment, a front load washing machine appliance is provided. The washing machine appliance may include a cabinet, a wash tub positioned within the cabinet, and a wash basket. The wash basket may be rotatably mounted within the wash tub and may be accessible through an opening in the cabinet. The washing machine appliance may further include a door mounted to a front of the cabinet. The door may be moveable between an open position and a closed position for selectively controlling access to the wash basket. The washing machine appliance may further include a vent line extending from the wash tub. The vent line may provide for a flow of air along a flow direction from the wash tub. The vent line may have a vent inlet positioned at the wash tub. The washing machine appliance may further include a vent filter disposed at the vent inlet to the vent line. The vent filter may include a plurality of louvers located adjacent to each other and spaced apart from each other so as to form a plurality of openings for the flow of air from the wash tub. Each louver may include an upstream face and a downstream face along the flow direction, a bottom portion and a top portion along a vertical direction, and a top lip extending from the top portion. The top lip may have an upstream surface forming an obtuse or right angle with the upstream face. The upstream face may be positioned so that fluid ejected from the wash basket during rotation of the wash basket may impinge upon the upstream face to deter fluid from travelling through the vent line. 
     In another exemplary embodiment, a front load washing machine appliance is provided. The washing machine appliance may include a cabinet, a wash tub positioned within the cabinet, a wash basket rotatably mounted within the wash tub and accessible through an opening in the cabinet and a door mounted to a front of the cabinet. The door may be moveable between an open position and a closed position for selectively controlling access to the wash basket. The washing machine appliance may further include a vent line. The vent line may extend from the wash tub. The vent line may provide for a flow of air along a flow direction from the wash tub. The vent line may have a vent inlet positioned at the wash tub. The washing machine appliance may further include a vent filter disposed at the vent inlet to the vent line. The vent filter may include a plurality of louvers located adjacent to each other and spaced apart from each other so as to form a plurality of openings for the flow of air from the wash tub. Each louver may have an upstream face and a downstream face. Each louver may further have a bottom portion and a top portion along a vertical direction. Along the top portion, each louver may further include a top lip forming a non-zero angle with respect to the upstream face. The upstream face may be positioned so that fluid ejected from the wash basket during rotation of the wash basket may impinge upon the upstream face to block fluid from travelling through the vent line. 
     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 
       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. 
         FIG.  1    provides a perspective view of a washing machine appliance according to exemplary embodiments of the present disclosure. 
         FIG.  2    provides a cross-sectional view of the exemplary washing machine appliance of  FIG.  1    taken along a plane that includes the transverse and vertical directions. 
         FIGS.  3  and  4    provide front schematic views and of an exemplary wash tub and wash basket depicting exemplary placements of a vent line. 
         FIGS.  5 A,  5 B and  5 C  illustrate an exemplary vent filter of the present invention in which  FIG.  5 A  is side view,  FIG.  5 B  is a perspective view, and  FIG.  5 C  is a cross-sectional view. 
         FIGS.  6 A and  6 B  illustrate another exemplary vent filter of the present invention in which  FIG.  6 A  is side view and  FIG.  6 B  is a perspective view. 
         FIGS.  7 A and  7 B  illustrate another exemplary vent filter of the present invention in which  FIG.  7 A  is side view and  FIG.  7 B  is a perspective view. 
         FIGS.  8 A and  8 B  illustrate another exemplary vent filter of the present invention in which  FIG.  8 A  is side view and  FIG.  8 B  is a perspective view. 
     
    
    
     Use of the same of similar reference numerals in the figures denotes the same or similar features unless the context indicates otherwise. 
     DETAILED DESCRIPTION 
     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 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. 
     In order to aid understanding of this disclosure, several terms are defined below. The defined terms are understood to have meanings commonly recognized by persons of ordinary skill in the arts relevant to the present invention. The terms “includes” and “including” are intended to be inclusive in a manner similar to the term “comprising.” Similarly, the term “or” is generally intended to be inclusive (i.e., “A or B” is intended to mean “A or B or both”). The terms “first,” “second,” and “third” may be used interchangeably to distinguish one element from another and are not intended to signify location or importance of the individual elements. Terms such as “inner” and “outer” refer to relative directions with respect to the interior and exterior of the washing machine appliance, and in particular the wash basket therein. For example, “inner” or “inward” refers to the direction towards the interior of the washing machine appliance. Terms such as “left,” “right,” “front,” “back,” “top,” or “bottom” are used with reference to the perspective of a user accessing the washing machine appliance. For example, a user stands in front of the washing machine appliance to open the door and reaches into the wash basket to access items therein. Furthermore, it should be appreciated that as used herein, terms of approximation, such as “approximately,” “substantially,” or “about,” refer to being within ten percent greater or less than the stated value. When used in the context of an angle or direction, such terms include within ten degrees greater or less than the stated angle or direction. For example, “generally vertical” includes directions within ten degrees of vertical in any direction, e.g., clockwise or counter-clockwise. 
     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 L, and between a front  112  and a rear  114  along the transverse direction T. Cabinet  102  is generally configured for containing or supporting various components of appliance  100  and which may also define one or more internal chambers or compartments of appliance  100 . In this regard, as used herein, the terms “cabinet,” “housing,” and the like are generally intended to refer to an outer frame or support structure for appliance  100 , e.g., including any suitable number, type, and configuration of support structures formed from any suitable materials, such as a system of elongated support members, a plurality of interconnected panels, or some combination thereof. It should be appreciated that cabinet  102  does not necessarily require an enclosure and may simply include open structure supporting various elements of appliance  100 . By contrast, cabinet  102  may enclose some or all portions of an interior of cabinet  102 . It should be appreciated that cabinet  102  may have any suitable size, shape, and configuration while remaining within the scope of the present subject matter. 
     A wash tub  120  is positioned within a cabinet  102  and is generally configured for retaining fluids during an operating cycle. As used herein, such fluids may include a “cleaning fluid” or “wash fluid” having water, detergent, fabric softener, bleach, or any other suitable wash additive or combination thereof. Such fluids may also include a “rinse fluid” that includes water and may have one or more additives. The terms “wash fluid” and the like may be used herein to generally refer to a liquid used for washing or rinsing clothing or other articles. For example, the wash fluid is typically made up of water that may include other additives such as detergent, fabric softener, bleach, or other suitable treatments (including combinations thereof). 
     A wash basket  122  is received within wash tub  120  and defines a wash chamber  124  that is configured for receipt of articles for washing. More specifically, wash basket  122  is rotatably mounted within wash tub  120  such that it is rotatable about an axis of rotation AR. According to the illustrated embodiment, the axis of rotation is substantially parallel to the transverse direction T. In this regard, washing machine appliance  100  is generally referred to as a “horizontal axis” or “front load” washing machine appliance  100 . 
     Wash basket  122  may define one or more agitator features that extend into wash chamber  124  to assist in agitation and cleaning articles disposed within wash chamber  124  during operation of washing machine appliance  100 . For example, as illustrated in  FIG.  2   , a plurality of ribs  126  extends from wash basket  122  into wash chamber  124 . In this manner, for example, ribs  126  may lift articles disposed in wash basket  122  during rotation of wash basket  122 . 
     Washing machine appliance  100  includes a drive assembly  128  which is coupled to wash tub  120  and is generally configured for rotating wash basket  122  during operation, e.g., such as during an agitation or spin cycle. More specifically, as best illustrated in  FIG.  2   , drive assembly  128  may include a motor assembly  130  that is in mechanical communication with wash basket  122  to selectively rotate wash basket  122  (e.g., during an agitation or a rinse cycle of washing machine appliance  100 ). According to the illustrated embodiment, motor assembly  130  is a pancake motor. However, it should be appreciated that any suitable type, size, or configuration of motors may be used to rotate wash basket  122  according to alternative embodiments. In addition, drive assembly  128  may include any other suitable number, types, and configurations of support bearings or drive mechanisms. 
     Referring generally to  FIGS.  1  and  2   , cabinet  102  also includes a front panel  140  that defines an opening  142  that permits user access to wash basket  122 . More specifically, washing machine appliance  100  includes a door  144  that is positioned over opening  142  and is rotatably, e.g., pivotably, mounted to front panel  140  (e.g., about a door axis that is substantially parallel to the vertical direction V). In this manner, door  144  permits selective access to opening  142  by being movable between an open position (not shown) facilitating access to a wash tub  120  and a closed position ( FIG.  1   ) prohibiting access to wash tub  120 . 
     A gasket  202  may be provided at opening  142  to seal door  144  when door  144  is in the closed position. For example, gasket  202  may extend between wash tub  120  and front panel  140 , e.g., generally along the transverse direction T and may extend about or around opening  142  such that gasket  202  is covered by door  144  when door  144  is in the closed position, and gasket  202  may promote sealing between door  144  and cabinet  102 , e.g., front panel  140  of cabinet  102  to help contain fluids including wash and rinse fluids. 
     In some embodiments, a window  146  ( FIG.  1   ) in door  144  permits viewing of wash basket  122  and articles therein when door  144  is in the closed position (e.g., during operation of washing machine appliance  100 ). Door  144  also includes a handle (not shown) that, for example, a user may pull when opening and closing door  144 . Further, although door  144  is illustrated as mounted to front panel  140 , it should be appreciated that door  144  may be mounted to another portion of cabinet  102  or any other suitable support according to alternative embodiments. 
     Referring again to  FIG.  2   , wash basket  122  also defines a plurality of perforations  152  in order to facilitate fluid communication between an interior of wash basket  122  and wash tub  120 . A sump  154  is defined by wash tub  120  at a bottom of wash tub  120  along the vertical direction V. Thus, sump  154  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 (e.g., by gravity) from wash basket  122  to sump  154  through the plurality of perforations  152 . A pump assembly  156  is located beneath wash tub  120  for gravity assisted flow when draining wash tub  120  (e.g., via a drain  158 ). Pump assembly  156  is also configured for recirculating wash fluid within wash tub  120 . Accordingly, pump assembly  156  may also be referred to or include a drain pump or a circulation pump. 
     Pump assembly  156  is located beneath wash tub  120  and is in fluid communication with sump  154  for periodically discharging wash and rinse fluids from washing machine appliance  100 . Pump assembly  156  may generally include a drain pump (not shown) which is in fluid communication with sump  154  and with an external drain  148  through a drain hose  150 . During a drain cycle, drain pump in pump assembly  156  urges a flow of wash fluid from sump  154 , through drain hose  150 , and to external drain  148 . 
     Referring still to  FIGS.  1  and  2   , in some embodiments, washing machine appliance  100  may include an additive dispenser or spout  170 . For example, spout  170  may be in fluid communication with a water supply  160  in order to direct fluid (e.g., clean water) into wash tub  120 . Spout  170  may also be in fluid communication with sump  154 . For example, pump assembly  156  may direct wash fluid disposed in sump  154  to spout  170  in order to circulate wash fluid in wash tub  120 . 
     As illustrated, a detergent drawer  172  may be slidably mounted within front panel  140 . Detergent drawer  172  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  172  may also be fluidly coupled to spout  170  to facilitate the complete and accurate dispensing of wash additive. 
     In some embodiments, an optional bulk reservoir  174  may be disposed within cabinet  102 . Bulk reservoir  174  may be configured for receipt of fluid additive for use during operation of washing machine appliance  100 . Moreover, bulk reservoir  174  may be sized such that a volume of fluid additive sufficient for a plurality or multitude of wash cycles of washing machine appliance  100  (e.g., five, ten, twenty, fifty, or any other suitable number of wash cycles) may fill bulk reservoir  174 . Thus, for example, a user can fill bulk reservoir  174  with fluid additive and operate washing machine appliance  100  for a plurality of wash cycles without refilling bulk reservoir  174  with fluid additive. A reservoir pump  176  may be configured for selective delivery of the fluid additive from bulk reservoir  174  to wash tub  120 . 
     A control panel  180  including a plurality of input selectors  182  may be coupled to front panel  140 . Control panel  180  and input selectors  182  collectively form a user interface input for operator selection of machine cycles and features. A display  184  of control panel  180  indicates selected features, operation mode, a countdown timer, or other items of interest to appliance users regarding operation. 
     Operation of washing machine appliance  100  is controlled by a processing device or a controller  186  that is operatively coupled to control panel  180  for user manipulation to select washing machine cycles and features. In response to user manipulation of control panel  180 , controller  186  operates the various components of washing machine appliance  100  to execute selected machine cycles and features. Controller  186  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 methods described herein. 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  186  may be constructed without using a microprocessor, e.g., using a combination of discrete analog 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  180  may be in communication with controller  186  via one or more signal lines or shared communication busses to provide signals to or receive signals from controller  186 . 
     In addition, the memory or memory devices of the controller  186  can store information or data accessible by the one or more processors, including instructions that can be executed by the one or more processors. It should be appreciated that the instructions can be software written in any suitable programming language or can be implemented in hardware. Additionally, or alternatively, the instructions can be executed logically or virtually using separate threads on one or more processors. 
     For example, controller  186  may be operable to execute programming instructions or micro-control code associated with an operating cycle of washing machine appliance  100 . In this regard, the instructions may be software or any set of instructions that when executed by the processing device, cause the processing device to perform operations, such as running one or more software applications, displaying a user interface, receiving user input, processing user input, etc. Moreover, it should be noted that controller  186  as disclosed herein is capable of and may be operable to perform any methods, method steps, or portions of methods as disclosed herein. For example, in some embodiments, methods disclosed herein may be embodied in programming instructions stored in the memory and executed by controller  186 . 
     The memory devices may also store data that can be retrieved, manipulated, created, or stored by the one or more processors or portions of controller  186 . The data can include, for instance, data to facilitate performance of methods described herein. The data can be stored locally (e.g., on controller  186 ) in one or more databases or may be split up so that the data is stored in multiple locations. In addition, or alternatively, the one or more database(s) can be connected to controller  186  through any suitable network(s), such as through a high bandwidth local area network (LAN) or wide area network (WAN). In this regard, for example, controller  186  may further include a communication module or interface that may be used to communicate with one or more other component(s) of washing machine appliance  100 , controller  186 , an external appliance controller, or any other suitable device, e.g., via any suitable communication lines or network(s) and using any suitable communication protocol. The communication interface can include any suitable components for interfacing with one or more network(s), including for example, transmitters, receivers, ports, controllers, antennas, or other suitable components. 
     In exemplary embodiments, during operation of washing machine appliance  100 , laundry items are loaded into wash basket  122  through opening  142 , and a wash operation is initiated through operator manipulation of input selectors  182 . For example, a wash cycle may be initiated such that wash tub  120  is filled with water, detergent, or other fluid additives (e.g., via detergent drawer  172  or bulk reservoir  174 ). One or more valves (not shown) can be controlled by washing machine appliance  100  to provide for filling wash basket  122  to the appropriate level for the amount of articles being washed or rinsed. By way of example, once wash basket  122  is properly filled with fluid, the contents of wash basket  122  can be agitated (e.g., with ribs  126 ) for an agitation phase of laundry items in wash basket  122 . During the agitation phase, wash basket  122  may be motivated about the axis of rotation AR at a set speed (e.g., first speed or tumble speed). As wash basket  122  is rotated, articles within wash basket  122  may be lifted and permitted to drop therein. 
     After the agitation phase of the washing operation is completed, wash tub  120  can be drained, e.g., by drain pump assembly  156 . Laundry articles can then be rinsed (e.g., through a rinse cycle) by again adding fluid to wash tub  120 , depending on the particulars of the cleaning cycle selected by a user. Ribs  126  may again provide agitation within wash basket  122 . One or more spin cycles may also be used. In particular, a spin cycle may be applied after the wash cycle or after the rinse cycle in order to wring fluid, (e.g., wash or rinse fluid) from the articles being washed. During a spin cycle, wash basket  122  is rotated at relatively high speeds. For instance, wash basket  122  may be rotated at one set speed (e.g., second speed or pre-plaster speed) before being rotated at another set speed (e.g., third speed or plaster speed). As would be understood, the pre-plaster speed may be greater than the tumble speed and the plaster speed may be greater than the pre-plaster speed. Moreover, agitation or tumbling of articles may be reduced as wash basket  122  increases its rotational velocity such that the plaster speed maintains the articles at a generally fixed position relative to wash basket  122 . After articles disposed in wash basket  122  are cleaned (or the washing operation otherwise ends), a user can remove the articles from wash basket  122  (e.g., by opening door  144  and reaching into wash basket  122  through opening  142 ). 
     It should be appreciated that the present subject matter is not limited to any particular style, or model of washing machine appliance. The exemplary embodiment depicted in  FIGS.  1  and  2    is simply provided for illustrative purposes only. Other washing machine appliances having different configurations, different appearances, or different features may also be utilized with the present subject matter as well. For example, different locations may be provided for the user interface, different configurations may be provided, e.g., two in one wash and dry machine appliances, and other differences may be applied as well. 
     During wash and rinse cycles, a pressure difference can build in wash chamber  124  during rotation of wash basket  122 . In accordance with exemplary aspects of the present disclosure, washing machine appliance  100  may include a vent damper  200  and vent line  210  to aid in equalization of pressure from within washing machine appliance  100 . 
     Vent damper  200  may be provided to selectively control an air flow F between wash tub  120  and the exterior or environment of appliance  100 . Generally, vent damper  200  is in fluid communication with wash tub  120  and vent line  210  as denoted by air flow path arrows F. In certain embodiments, vent damper  200  is enclosed, at least in part, within cabinet  102 . Vent damper  200  may be selectively controlled or operated to permit or preclude the flow of air from the ambient environment into the interior of cabinet  102 , such as to wash tub  120 , during certain operations, phases, or cycles. Along air flow path F, vent damper  200  may be positioned between aperture  204  and wash tub  120  or between an aperture  204  and gasket  202 . Opening vent damper  200  permits fluid communication or air flow into washing machine appliance  100 . 
     For this exemplary embodiment, vent damper  200  is positioned upstream of the internal components, e.g., wash basket  122 , with respect to a flow of ambient air F from the exterior of washing machine appliance  100 . Accordingly, air flow F may travel through vent damper  200 , into and through wash basket  122  and wash chamber  124  therein and may exit washing machine appliance  100  via vent line  210  by entering vent line  210  at a vent inlet  214 , flowing through vent line  210 , and returning to the exterior via vent outlet  216 . Such air flow may be created by convective flow or rotation of wash basket  122 . For example, rotation of wash basket  122 , including ribs  126  therein, can create centrifugal forces pushing the air around to promote circulation of the ambient air through washing machine appliance  100 , e.g., into and through wash basket  122  along air flow F. In some embodiments, a fan (not shown), may aid in the flow of air F through washing machine appliance  100 . In other exemplary embodiments, washing machine  100  may have other air flow systems having different configurations and features. 
     For this exemplary embodiment, vent line  210  extends between wash tub  120  and cabinet  102 . Vent inlet  214  is located at wash tub  120  near an outer circumferential surface  240  of wash tub  120 . As used herein, the term “at” may include touching, nearby, positioned coincident with, or immediately adjacent to. Vent line  210  extends in the transverse direction T and ends at vent outlet  216 . Vent line  210  maybe cylindrical in shape, may be constructed from a conduit, may include various bends or other configurations as desired for specific embodiments. Other shapes and constructions may be used as well. For this exemplary embodiment, vent outlet  216  of vent line  210  is located at back  114  of cabinet  102 . Vent outlet  216  may be located at any other discrete position on cabinet  102 , including top  104 , bottom  106 , left side  108 , right side  110 , or front  112 . Regardless of location, vent outlet  216  allows air flow F to flow out of vent line  210  and out of washing machine appliance  100 . 
     In some embodiments, vent line  210  may be located at wash tub  120 . Vent line  210  may allow air to flow from wash tub  120 . In some embodiments, vent line  210  may have a vent outlet (not shown) that is within cabinet  102 . In certain embodiments, vent line  210  may have a return flow pattern, allowing air to flow from wash tub  120 , into vent line  210  and then out of vent line  210  at a vent outlet that returns to a position on wash tub  120  separate from a position of a vent inlet along vent line  210  positioned on wash tub  120 . 
     Referring to  FIGS.  3  and  4   , for this exemplary embodiment, vent inlet  214  of vent line  210  is positioned above a lateral midline LM of wash basket  122  and may be positioned anywhere along lateral direction L between, or coincident with, a vertical midline VM and a vertical tangent VT to outer circumferential surface  240  of wash tub  120 .  FIGS.  3  and  4    illustrate exemplary placements for vent inlet  214 . In  FIG.  3   , vent inlet  214  is located at wash tub  120  near wash basket  122 , and at a point midway along lateral direction L between vertical midline VM and vertical tangent VT. In  FIG.  4   , vent inlet  214  is located immediately adjacent to vertical tangent VT of wash tub  120 . Other positions may be used as well. 
     As discussed above, during rotation of wash basket  122 , fluid can be urged by centrifugal forces from wash basket  122  through perforations  152 . Such fluid could undesirably enter vent line  210 , which is not intended as a pathway for cleaning fluids (e.g., wash or rinse fluid) to exit wash tub  120 . Accordingly, in accordance with exemplary aspects of the present disclosure, washing machine appliance  100  may further include a vent filter  212  to allow air to flow through washing machine appliance  100  while keeping cleaning fluids (e.g., wash or rinse fluid) within wash tub  120 . 
       FIGS.  5 A,  5 B, and  5 C , illustrate an exemplary embodiment of a vent filter  212  disposed at vent inlet  214 . Vent filter  212  is located at wash tub  120  near outer circumferential surface  240  of wash tub  120 . For this exemplary embodiment, vent filter  212  is configured as internal feature within vent line  210 . Vent filter  212  may be insertable within vent line  210  using, for example, a groove  213  in a vent filter casing  256  for orientation. In some embodiments, vent filter  212  connects with vent line  210  with clips, snaps, screws, threaded ends, bent ends, or other shaped end to fit with vent line  210 . For this embodiment, vent filter  212  lies within a plane that includes lateral direction L and transverse direction T. 
     Vent filter  212  is positioned to allow air flow F out of wash tub  120  and through vent line  210  while deterring fluids (arrows W), such as wash or rinse liquids, from travelling along flow path F through vent line  210 . To aid in deterring fluid W from flowing through while allowing air flow F to pass through vent line  210 , vent filter  212  includes a plurality of louvers  218  located adjacent to each other and spaced apart from each other in an equidistant manner so as to form a plurality of openings  220  for the flow of air F from wash tub  120  through vent line  210 . Vent filter casing  256  includes an inside circumferential surface  258  to which each louver  218  is attached at ends  260 . 
     For this exemplary embodiment, louvers  218  are divided by a central beam  252  located in the middle of filter  212  and extending between opposing sides of vent filter casing  256 . Central beam  252  has a connecting surface  254  to which louvers  218  are connected. Connecting surface  254  lies in a vertical plane. Each louver  218  has two ends  260 , a first end  260  attached to central beam  252  at connecting surface  254  and a second end  260  attached to vent filter casing  256  at circumferential surface  258 . 
     Relative to air flow direction F, louvers  218  include an upstream face  222  and a downstream face  224 . Upstream face  222  faces generally toward wash tub  120 . Upstream face  222  is upstream in relation to air flow F such that air flow F and liquid or fluid flow F generally encounters upstream face  222  before downstream face  224 . Stated alternatively, upstream face  222  faces oncoming air flow F as it travels to vent line  210 . Upstream face  222  is positioned so that fluid ejected from wash basket  122  impinges upon upstream face  222  to deter fluids W from passing into or through vent line  210 . For this exemplary embodiment, upstream face  222  is planar and forms a louver angle LV with the horizontal direction. In certain embodiments, upstream angle LV is in a range between about 30 and about 60 degrees. In certain embodiments, upstream angle LV is about 45 degrees. 
     Each louver  218  further includes a bottom portion  226  and a top portion  228  that are offset from each other along vertical direction V. In general, top portion  228  is a vertically upper portion of louver  218  while bottom portion  226  is a vertically lower portion. Top portion  228  is along an upper half of louver  218  while bottom portion  226  is a vertically lower half of louver  218 . Both top portion  228  and bottom portion  226  attach to central beam  252  at connecting surface  254  and attach to vent filter casing  256  at circumferential surface  258 . 
     A top lip  230  extends from top portion  228  and has an upstream surface  232  that extends upstream face  222  of each louver  218 . For this exemplary embodiment, upstream surface  232  extends outwardly and horizontal—i.e., parallel to lateral direction L and transverse direction T. Upstream surface  232  forms an upstream angle UV ( FIG.  5 C ) with upstream face  222  to create a top corner  262  between top lip  230  and top portion  228 . As shown, upstream angle UV is an obtuse angle. In certain embodiments, upstream angle UV may be between about 120 and about 150 degrees. In certain other embodiments, upstream angle UV is about 135 degrees. Top lip  230  aids in redirecting fluid impinging on louver  218  toward wash tub  120 , while allowing air flow along air flow path F to flow past top lip  230  and through vent line  210 . 
     Referring particularly to  FIG.  5 C , during operation of appliance  100 , fluid W ejected from wash basket  122  during rotation in a counter-clockwise direction (CCW in  FIGS.  3  and  4   ) impinges upon upstream face  222  and upstream surface  232 , which are configured (e.g., angled relative to vertical direction V) to deter fluids from entering vent line  210 . Fluids impinging on upstream face  222  and upstream surface  232  fall back toward wash tub  120  as indicated by arrows D. As will be understood by one of skilled in the art using the teachings disclosed herein, the present invention is not limited to wash basket  122  that is only rotated in counter-clockwise direction (arrows CCW in  FIGS.  3  and  4   ) and may be used with rotations in a clock-wise direction (arrows CW in  FIGS.  3  and  4   ) as well. Vent inlet  214  may be located on either side of vertical midline VM along lateral direction L. 
     For the exemplary embodiment of  FIGS.  5 A through  5 C , upstream face  222  is planar.  FIGS.  6 A and  6 B  illustrates another embodiment of filter  212  in which upstream face  222  of louvers  218  is curved. In addition, for this embodiment, top lip  230  extends downwardly from top portion  228  and parallel to vertical direction V—thereby providing an upstream surface  232  that is parallel to vertical direction V. 
       FIGS.  7 A and  7 B  illustrates another exemplary embodiment of filter  212  in which upstream face  222  of louvers  218  is planar. As with the embodiment of  FIGS.  5 A through  5 C , top lip  230  extends from top portion  228  and provides an upstream surface  232  that extends upstream face  222  of each louver  218 . Upstream surface  232  extends outwardly and horizontal—i.e., parallel to lateral direction L and transverse direction T. Upstream surface  232  forms an upstream angle UV with upstream face  222  to create top corner  262  between top lip  230  and top portion  228 . As shown, for this exemplary embodiment, upstream angle UV forms a right angle or an angle of 90 degrees. 
     Additionally, for the embodiment of  FIGS.  7 A and  7 B , each louver  218  further includes a bottom lip  234  forming a bottom corner  264  with bottom portion  226  on each louver  218 . Bottom lip  234  extends from bottom portion  226 , in a direction opposite to the direction top lip  230  extends from top portion  228 . Bottom lip  234  may be parallel to top lip  230  as shown. 
     Bottom lip  234  has a bottom upstream surface  236 . Bottom upstream surface  236  of bottom lip  234  extends along a direction that is parallel to the horizontal direction or lies in a plane include the lateral and transverse directions. Bottom upstream surface  236  forms a bottom angle BV with upstream face  222 . Bottom angle BV is a reflex angle. Bottom lip  234  further forms bottom corner  264  with downstream face  224 . Bottom corner  264  is an inner corner. Bottom lip  234  forms a bottom outer corner  265  between bottom upstream surface  236  and upstream face  222 . Bottom lip  234  aids in redirecting fluid impinging on louver  218  toward wash tub  120 , while allowing air flow along air flow path F to flow past bottom lip  234  and through vent line  210 . Bottom lip  234  is further offset from top portion  228  and top lip  230  along vertical direction V. 
     In other embodiments of the invention, the configuration of louvers  218  in filter  212  may be varied in other aspects including, e.g., the number of louvers, shape of each louver, and relative physical dimensions. For example,  FIGS.  8 A and  8 B  provide another exemplary embodiment of filter  212  in which louvers  218  have a different overall length and vary in number from previous embodiments. The increased length may improve the ability to redirect fluids back towards wash tub  120 . 
     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.