Patent Publication Number: US-11655580-B2

Title: Washer appliance with removable agitator post having twist lock mechanism

Description:
FIELD OF THE INVENTION 
     The subject matter of the present disclosure relates generally to a washer appliance having a removable agitator post. 
     BACKGROUND OF THE INVENTION 
     Washing appliances (also referred to as “washing machines”) typically include a drum or basket for receipt of articles to be washed. Top-load or vertical axis washing machines rotate the drum about the vertical axis at various points during the cleaning cycle. Various components provide for adding fluid into the drum and for imparting motion to the fluid and articles being washed in order to clean the articles. 
     Conventionally, the washing appliance may include a knob or other switch by which the user selects the level of fluid in the vertical axis washing machine based on e.g., the load size of articles being washed. The user visually determines the desired fluid level based on the anticipated load size. Many washing appliance users are also accustomed to seeing a conventional agitator in the form of a post extending up from the bottom of the wash basket and configured to impart motion to the fluid and articles during the cleaning cycles. Users may associate factors such as fluid level and movement of the agitator as directly related to the effective cleaning of the articles and may believe that increased fluids levels and agitator action are advantageous. 
     Certain articles may require more wash space within the wash drum. For example, large garments, pillows, comforters and the like may require more volume for washing than typical articles of clothing. Sufficient space is required in order for the washing appliance to be able to impart motion to the articles and wash fluid as part of the cleaning process. Conventional agitator designs having a post that extends into the wash basket necessarily consume at least part of this space. In addition, in such designs the agitator is typically not designed for removal by the user of the appliance. 
     Improvements in technology and increasing water conservation requirements have resulted in washing appliances that can use less water during the cleaning cycle and may use features other than the conventional post-type agitator for imparting the desired movement of the articles within the wash basket or wash drum. For example, rotatable impellers have been developed that can impart the desired movement while consuming less volume inside the wash drum than the conventional agitator. Some washing appliances utilizing such designs may also be able to use less water during the cleaning cycle as well. 
     However, user perception of washing machine features that provide for the best cleaning experience may contradict the actual impact of such features. As previously mentioned, consumers familiar with a conventional post-type agitator extending vertically from the bottom of the wash drum may be reluctant to purchase or use a vertical-axis washing appliance lacking such feature. Yet, depending on the particular design employed, an impeller located at the bottom of the wash drum may have more impact in creating the desired agitation and cleaning of articles than the conventional agitator—including under conditions of less water usage. And for larger loads or loads with larger articles, the space consumed by the conventional post-type agitator is needed for the articles. 
     Accordingly, a washing appliance with a removable agitator would be useful. More particularly, a washing appliance that allows the user to readily install or remove an agitator while still providing for effective cleaning of articles would be beneficial. Such as washing appliance that can allow of the installation or removal without requiring special tools would be particularly beneficial. 
     BRIEF DESCRIPTION OF THE INVENTION 
     Additional aspects and 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. 
     In one exemplary embodiment, the present invention provides a washing appliance including a cabinet and a wash tub positioned in the cabinet and defining a wash chamber. A wash drum is rotatably mounted within the wash chamber and is configured for receiving articles for washing. An impeller is positioned in the wash drum. The impeller is rotational about a vertical axis and is configured for imparting motion to the articles during washing. The impeller may include a receptacle, a plurality of grooves extending along a circumferential direction about the receptacle, a plurality of notches with each notch connected with one of the plurality of grooves and extending along a vertical direction, and a plurality of access channels with each access channel connected with one of the plurality of grooves and extending along the vertical direction. 
     An agitator post can be configured for removable positioning in the receptacle of the impeller, the agitator post having a top end and a bottom end. The agitator post may include a plurality of agitator tabs proximate the bottom end that project along a radial direction and are configured for movement along the circumferential direction within the plurality of grooves and movement along the vertical direction within the plurality of notches and the plurality of access channels. A biasing element may be positioned between the impeller and agitator post when the agitator post is received in the receptacle, the biasing element configured for urging the agitator post upwardly along the vertical direction within the receptacle. 
     In another exemplary embodiment, the present invention may include a washing appliance. A wash drum may be rotatably mounted within a wash chamber and configured for receiving articles for washing. An impeller may be positioned in the wash drum, the impeller being rotational about a vertical axis and configured for imparting motion to the articles during washing. A receptacle may be centrally located on the impeller, the receptacle defining a recess. A plurality of access channels may be located within the recess and spaced apart along a circumferential direction. A plurality of notches may be located within the recess and spaced apart along a circumferential direction. A plurality of grooves may be located within the recess, each of the grooves extending longitudinally along a circumferential direction between one of notches and one of the access channels. 
     An agitator post can be removably positioned within the receptacle, the agitator post extending along the vertical axis between a top end and a bottom end. A plurality of agitator tabs may extend along a radial direction from the bottom end of the agitator post, the agitator tabs configured for sliding movement within the access channels, notches, and grooves. A spring may be positioned between the impeller and the agitator post when the agitator post is in the receptacle, the spring configured to urge the agitator post upwardly along the vertical axis. 
     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, in which: 
         FIG.  1    provides a partial perspective view of an exemplary embodiment of a washing machine of the present invention. 
         FIG.  2    provides a front cross-sectional view of the exemplary washing machine of  FIG.  1   . 
         FIG.  3    provides a perspective view of an exemplary impeller used with an article movement mechanism of the present invention. 
         FIG.  4    provides an exploded view of an exemplary article movement mechanism of the invention included the impeller of  FIG.  3   . 
         FIG.  5    is a close-up perspective view of the exemplary impeller of  FIG.  3   . 
         FIGS.  6  and  7    are cross-sectional views of a portion of the exemplary article movement mechanism of  FIGS.  3  through  5   . In  FIG.  7   , an exemplary agitator post is shown in a receptacle of the exemplary impeller. 
         FIG.  8    is a partial perspective view of the bottom end of an exemplary agitator post of the present invention. 
         FIG.  9    is another partial perspective view of the exemplary bottom end. 
         FIG.  10    is a close-up perspective view of another exemplary embodiment of an impeller of the present invention. 
         FIG.  11    is a perspective view of an exemplary embodiment of a removable cap. 
         FIG.  12    is a close-up perspective view of the exemplary cap of  FIG.  11    received in a recess of the exemplary impeller of  FIG.  10   . 
         FIG.  13    is an exploded view of an exemplary biasing element and the exemplary impeller of  FIG.  10   . 
         FIG.  14    is close-up, cross-sectional view of the exemplary embodiment of the impeller in  FIG.  10    with the exemplary agitator post of  FIGS.  8  and  9    installed therein. 
         FIG.  15    is an exploded perspective view of another exemplary article movement mechanism of the present invention. 
         FIG.  16    is a cross-sectional view of the bottom end of the exemplary agitator post depicted in  FIG.  15   . 
         FIG.  17    is a close-up perspective view of the exemplary impeller depicted in  FIG.  15   . 
         FIG.  18    is a close-up, cross-sectional view of the exemplary embodiment of the impeller in  FIG.  15    with the exemplary agitator post of  FIGS.  15  and  16    installed therein. 
         FIG.  19    is a schematic view of features provided by an exemplary receptacle as may be used for securing or releasing an agitator post. 
         FIG.  20    is a schematic view of features provided by another exemplary receptacle as may be used for securing or releasing an agitator post. 
     
    
    
     The use of the same or similar reference numbers in the figures denotes same or similar features unless the context indicates otherwise. 
     DETAILED DESCRIPTION OF THE INVENTION 
     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. 
       FIGS.  1  and  2    illustrate an exemplary embodiment of a vertical axis washing appliance  100  of the present invention, which is also sometimes referred to as a top loading or vertical axis washing machine. In  FIG.  1   , a door  103  (shown in  FIG.  2   ) has been removed for purposes of illustrating other features of the invention. Washing machine appliance  100  has a cabinet  104  that extends between a top portion  106  and a bottom portion  108  along the vertical direction V, between a first side (left)  110  and a second side (right)  112  along the lateral direction L, and between a front  114  and a rear  116  along the transverse direction T. The present invention is not limited to the particular vertical axis washing appliance  100  shown in the figures. Using the teachings disclosed herein, one or skill in the art will understand the other embodiments of a washing machine are also in the scope of the present invention. 
     As best shown in  FIG.  2   , a wash tub  118  is positioned within cabinet  102 , defines a wash chamber  120 , and is generally configured for retaining wash fluids during an operating cycle. A wash drum  122  is rotatably mounted within wash chamber  120  of wash tub  118 . Washing machine appliance  100  further includes a dispenser  124  for dispensing wash fluid into wash tub  118 . In addition, appliance  100  may include one or more additional dispensers for directing fluid into wash tub  118  and each dispenser may be separately controlled by one or more valves controlling flow to each dispenser independently of the others. The term “wash fluid” refers to a liquid used for washing and/or rinsing articles during an operating cycle and may include any combination of water, detergent, fabric softener, bleach, and other wash additives or treatments. As used herein, the term “cleaning cycle” includes a wash cycle, rinse cycle, spin cycle, or combinations thereof. 
     Wash drum  122  and cabinet  104  generally define an opening  126  (accessible through door  103 ) for receipt of articles for washing. Wash drum  122  rotates about a vertical axis of rotation VA ( FIGS.  2  and  3   ) powered by motor assembly  128 . According to the illustrated embodiment, the axis of rotation VA is substantially parallel to the vertical direction V. As used herein, terms of approximation, such as “approximately,” “substantially,” or “about,” refer to being within a ten percent margin of error. 
     As illustrated, cabinet  104  of washing machine appliance  100  has a top panel  130 . Top panel  130  defines an opening ( FIG.  1   ) that coincides with opening  126  of wash tub  118  to permit a user access to wash drum  122 . Door  103  is rotatably mounted to top panel  130  to permit selective access to opening  126 . In particular, door  103  selectively rotates between a closed position and an open position. In the closed position, door  103  inhibits access to wash drum  122 . Conversely, in the open position, a user can access wash drum  122 . Although door  103  is illustrated as mounted to top panel  130 , door  103  may alternatively be mounted to cabinet  104  or any other suitable support. 
     As best shown in  FIG.  2   , wash drum  122  further defines a plurality of perforations  132  to facilitate fluid communication between an interior of wash drum  122  and wash tub  118 . In this regard, wash drum  122  is spaced apart from wash tub  118  to define a space for wash fluid to escape wash chamber  120 . During a spin cycle, wash fluid within articles being washed (e.g., clothing) and within wash chamber  120  is urged through perforations  132  wherein it may collect in a sump  134  defined by wash tub  118 . Washing machine appliance  100  further includes a pump assembly  148  ( FIG.  2   ) that is located beneath wash tub  118  and wash drum  122  for gravity assisted flow when draining wash tub  118 . 
     An exemplary article movement mechanism  200 , including impeller  204  ( FIGS.  2  and  3   ) and agitator post  202 , is rotatably mounted within wash drum  122  to impart motion to articles and liquid in wash drum  122 . More specifically, impeller  204  and agitator post  202  extend into wash drum  122  and assist agitation of articles disposed within wash drum  122  (as will be later described) during operation of washing appliance  100 , e.g., to facilitate improved cleaning. For this exemplary embodiment, agitator post  202  includes one or more helical vanes  210  extending from the outer surface  212  of agitator post  202  and extending vertically between bottom end  216  and top end  214  thereof. Helical vanes  210  may be configured to assist the agitation of articles or support the overall desired motion thereof during a cleaning cycle. As will be understood by one of skill in the art using teachings disclosed herein, helical vanes  210  may have different shapes, thickness, and other features from what is depicted in the figures and may actually include multiples sets of overlapping or non-overlapping vanes. 
     In different embodiments, impeller  204  and agitator post  202  may rotate separately or together. Such rotations include a single action element (i.e., oscillatory only), a double action element (oscillatory movement at one end, single direction rotation at the other end) or a triple action element (oscillatory movement plus single direction rotation at one end, single direction rotation at the other end). Impeller  204 , agitator post  202 , and wash drum  122  are oriented to rotate about a vertical axis of rotation VA (which is substantially parallel to vertical direction V). For example, impeller  204  and/or agitator post  202  may rotate back and forth in alternate directions about vertical axis VA during a cleaning cycle. Additional description of the actions of impeller  204  and agitator post  202  are set forth below. 
     As stated, washing machine appliance  100  includes a motor assembly  128  in mechanical communication with wash drum  122  to selectively rotate wash drum  122  (e.g., during a wash cycle or a rinse cycle of washing machine appliance  100 ). In addition, motor assembly  128  may also be in mechanical communication with impeller  204  and agitator post  202 . For example, impeller  204  may be connected with assembly  128  using a fastener  254  that attaches impeller  204  to a shaft  252  from assembly  128 . Motor assembly  128  may be configured for selectively and independently rotating or oscillating wash drum  122 , impeller  204 , and/or agitator post  202  during various operating cycles of washing machine appliance  100 . 
     Referring still to  FIGS.  1  through  3   , a control panel  138  with at least one input selector  140  ( FIGS.  1  and  2   ) extends from top panel  130 . Control panel  138  and input selector  140  collectively form a user interface input for operator selection of machine cycles and features of washing appliance  100 . A display  142  of control panel  138  indicates selected features, operation mode, a countdown timer, and/or other items of interest to appliance users regarding operation. 
     Operation of washing machine appliance  100  is controlled by at least one controller or processing device  146  that is operatively coupled to control panel  138  for user manipulation to select washing machine cycles and features. In response to user manipulation of control panel  138 , controller  146  operates the various components of washing machine appliance  100  to execute selected machine cycles and features. According to an exemplary embodiment, controller  146  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. Alternatively, controller  146  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  138  and other components of washing machine appliance  100  may be in communication with controller  146  via one or more signal lines or shared communication busses. 
     During operation of washing machine appliance  100 , laundry items are loaded into wash drum  122  through opening  126 , and washing operation is initiated through operator manipulation of input selector  140 . Water, detergent and/or other fluid additives can be added to wash tub  118  and wash drum  122  through dispenser  124  and/or other dispensers as well. Controller  146  can operate one or more valves of washing appliance  100  to provide for filling wash tub  118  and wash drum  122  to the appropriate level for the amount of articles being washed and/or rinsed. By way of example for a wash mode, once wash drum  122  is properly filled with fluid, the contents of wash drum  122  can be agitated (e.g., with article movement mechanism  200  as discussed previously) for washing of laundry items in wash drum  122 . The specific operation of wash appliance  100  by controller  146  will depend on various inputs including the cycle and other settings that may be selected by the user, the amount of article placed in wash chamber  120 , and other variables as will be understood by one of skill in the art using the teachings disclosed herein. 
     By way of continuing example, after wash tub  118  is filled and the agitation phase of the wash cycle is completed, wash tub  118  and drum  122  can be drained, e.g., by drain pump assembly  148 . Laundry articles can then be rinsed by again adding fluid to wash drum  122  and tub  118  again depending on the specifics of the cleaning cycle selected by a user. The impeller  204  and/or agitator post  202  may also provide agitation within wash drum  122 . One or more spin cycles may also be used as part of the cleaning process. 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 spin cycle, wash drum  122  is rotated at relatively high speeds to help wring fluid from the laundry articles through perforations  132 . After articles disposed in wash drum  122  are cleaned and/or washed, the user can remove the articles from wash drum  122 , e.g., by reaching into wash drum  122  through opening  126 . 
     As will now be further described, the exemplary article movement mechanism  200  allows desired movements to be imparted to articles in wash drum  122  during a cleaning cycle. These movements, which can include combinations of movement along vertical direction V and radial direction R, assist in cleaning articles while in the wash fluid. One exemplary pattern of movement will now be described. Using the teachings disclosed herein, one of skill in the art will understand that other patterns or paths of fluid and/or article movement in drum  122  may be used as well in other embodiments of the invention. 
     For example, after articles to be cleaned and fluid are loaded into cylindrical wash drum  122 , rotations of impeller  204  may impart an inverse toroidal motion to articles in wash drum  122  during a cleaning cycle. In such motion, articles may move vertically upward from impeller  204  along agitator post  202  and then radially outward (the radial direction is indicated by arrow R in  FIG.  3   , which is a direction perpendicular to vertical axis VA) at the top of an article load towards the cylindrical portion  123  of wash drum  122 . 
     The articles then move vertically downward towards impeller  204  and radially inward along the bottom of an article load towards agitator post  202  where the cycle repeats under the influence of components such as impeller  204 . Accordingly, during a cleaning cycle, this inverse toroidal motion results generally in a turnover of articles in wash drum  122 . As used herein, “inverse toroidal motion” or “inverse toroidal movement” does not refer to the specific movement necessarily of any individual article but to the overall movement of articles in wash drum  122  instead. A variety of factors create the inverse toroidal motion the occurs in wash drum  122  including, for example, the relative amounts of fluid and articles present in drum  122 , the shape of wash drum  122 , the configuration and movements of agitator post  202 , the configuration and movements of impeller  204 , and other factors as well. 
     With reference to  FIG.  3   , for this exemplary embodiment of mechanism  200 , impeller  204  includes a plurality of radial lobes  206  spaced apart along circumferential direction C. Each lobe  206  has thickness T as measured along the circumferential direction C that varies moving along radial direction R. For the exemplary embodiment shown, thickness T narrows and then widens moving along radial direction R and away from agitator post  202 . Each lobe  206  also has a height H above impeller base  208  along axial direction A that also varies along radial direction R. For the exemplary embodiment shown, height H gradually decreases moving along radial direction R and away from agitator post  202 . Impeller  204  as depicted in  FIGS.  2  and  3    is provided by way of example only. Other shapes and configurations may be used as well. 
     As noted, the configuration of impeller  204  assists in creating the desired movement of fluid and/or articles within wash drum  122 . Article movement mechanism  200  also includes an agitator post  202  which may assist in providing or supporting the desired movement. In addition, using features as will also be described, agitator post  202  can be readily installed or removed by a user of appliance  100  without the use of special tools. Removal of agitator post  202  allows more volume within wash drum  122  for the receipt of articles and/or fluid. At the same time, agitator post  202  can be readily installed as may be needed for a particular movement of articles in drum  122  or as may be based on e.g., user preference. An exemplary embodiment of agitator post  202  is set forth in the figures and will now be further described. 
     Referring to  FIGS.  3  through  9    and  FIG.  19   , for this exemplary embodiment, agitator post  202  is removably positioned in a receptacle  218  supported by impeller  204 . Receptacle  218  is centrally located on impeller  204  and may be an integral part of impeller  204  or could be a discrete component added to impeller  204 . Receptacle  218  defines a recess  220  ( FIGS.  4  and  5   ) into which the bottom end  216  of agitator post  202  can be removably inserted through removable collar  256 . The connection between agitator post  202  and impeller  204 , which will be further described, allows for the transfer of torque to agitator post  202  during a cleaning cycle while also allowing a user to readily remove or replace agitator post  202 . 
     Receptacle  218  includes an interior surface  221  that extends circumferentially about recess  220  and includes multiples features for selectively securing or releasing agitator post  202 . These features are configured to receive a plurality of agitator tabs  228  positioned proximate to bottom end  216  of agitator post  202 . Agitator tabs  228  project along radial direction R and are configured for movement along circumferential direction C and vertical direction V within multiple features provided by receptacle  218 . The features within receptacle  218  may vary in different embodiments of the invention. 
     For the exemplary embodiment of  FIGS.  3  through  9    and  FIG.  19   , receptacle  218  includes a plurality of grooves  222  that extend along a circumferential direction C about receptacle  218 . A plurality of access channels  226  are spaced apart along circumferential direction C. Each access channel  226  is connected with one of the grooves  222  at a first end  262  of such groove  222 . A plurality of notches  224  are spaced apart along circumferential direction C. Each notch  224  is connected with one of the grooves  222  at a second end  264  of such groove  222 . Accordingly, each groove extends longitudinally along circumferential direction C between a notch  224  and an access channel  226 . 
     Each access channel  226  extends along vertical direction V, which is parallel to vertical axis VA. Each access channel  226  is open at a top end  258  and extends vertically to a closed end  260 . For this exemplary embodiment, closed end  260  is positioned below channel  226 . Each notch  224  extends vertically upward from a respective groove  222 . 
     As stated, at bottom end  216 , agitator post  202  includes a plurality of agitator tabs  228  that project outwardly along radial direction R and are spaced apart along circumferential direction C. Agitator tabs  228  have height along vertical direction V and a width along circumferential direction C that allows for sliding movement within access channels  226 , circumferential grooves  222 , and notches  224 . The alignment and number of agitator tabs  228  matches a corresponding alignment and number of access channels  226 , circumferential grooves  222 , and notches  224 . 
     For this exemplary embodiment, a cap  232  is positioned within the recess  220  of receptacle  218 . Cap  232  is movable along vertical direction V between an up position shown in  FIGS.  3  and  6    and a down position shown in  FIG.  7   . Similar to agitator tabs  228 , cap  232  includes a plurality of cap tabs  234  that project outwardly along radial direction R. Cap tabs  234  have a width along circumferential direction C that allows for sliding movement along vertical direction V within access channels  226  between the up position and the down position. 
     Cap  232  defines a cap recess  236  within a cylindrically-shaped wall  238 . A biasing element or spring  230  is positioned in cap recess  236 . As such, biasing element  230  is positioned between impeller  204  and agitator post  202  when agitator post  202  is in receptacle  218 . The compression of biasing element  230  causes it to apply a force that urges agitator post  202  upwardly along vertical direction V or vertical axis VA when in receptacle  218 . 
     For the exemplary embodiment of  FIGS.  3  through  9    and  FIG.  19   , a user can install agitator post  202  into receptacle  218  by vertically aligning agitator tabs  228  with access channels  226 . Once aligned, agitator post  202  can be moved downwardly along vertical axis VA, which results in bottom end  216  pressing upon cap  232 . As cap  232  moves downwardly, cap tabs  234  slide downwardly in access channels  226  until reaching closed end  260 . Cylindrically-shaped wall  238  is received into a circumferentially-extending slot  240  defined by receptacle  218 . At the same time, agitator tabs  228  move into access channels  226  and move downwardly along vertical axis VA. Upon reaching the height of grooves  222 , the user can rotate agitator post  202 , which causes agitator tabs  228  to move from first end  262  to second end  264 . Upon reaching second end  264 , the user can release agitator post  202 , which allows biasing element  230  to urge agitator post  202  upwardly. Agitator tabs  228  will move upwardly along vertical axis VA until received into notches  224 . This secures the position of agitator post  202  and allows torque from impeller  204  to be transferred to agitator post  202 . 
     The user can remove agitator post  202  by simply reversing the movement just described for installation. Upon removal, biasing element  230  will return cap  232  to the up position, keeping recess  220  of receptacle  218  closed as shown in  FIG.  3   . As such, this embodiment of article movement mechanism  200  allows washing appliance  100  to be used with or without agitator post  202 . When agitator post  202  is not present, cap  232  precludes articles from migrating into recess  220  while also providing improved aesthetics. 
     Another exemplary embodiment of the invention is shown in  FIGS.  10  through  14    and  FIG.  20   . This embodiment may use the same agitator post  202  with tabs  228  as previously described. Similarly, for this exemplary embodiment, agitator post  202  is also removably positioned in a receptacle  218  supported by impeller  204 , and the connection between agitator post  202  and impeller  204  similarly allows for the transfer of torque to agitator post  202  during a cleaning cycle while also allowing a user to readily remove or replace agitator post  202 . Receptacle  218  again includes multiples features on interior surface  221  for selectively securing or releasing agitator post  202 . While these features are configured to receive agitator tabs  228  and allow for movement along circumferential direction C and vertical direction V, as shown in  FIG.  20   , such features differ somewhat from the previously described embodiment. 
     More particularly, in this embodiment, receptacle  218  includes a plurality of grooves  222  that extend along a circumferential direction C about receptacle  218  ( FIG.  20   ). A plurality of access channels  226  are spaced apart along circumferential direction C. Each access channel  226  is connected with one of the grooves  222  at a first end  262  of such groove  222 . A plurality of notches  224  are spaced apart along circumferential direction C. Each notch  224  is connected with one of the grooves  222  at a second end  264  of such groove  222 . Each notch  224  extends vertically upward from a respective groove  222 . Each access channel  226  extends along vertical direction V, which is parallel to vertical axis VA. Each access channel  226  is open at a top end  258  and extends vertically to a groove  222 —but does not extend vertically below channel  226 . 
     As with the previous embodiments, agitator tabs  228  have height along vertical direction V and a width along circumferential direction C that allows for sliding movement within access channels  226 , circumferential grooves  222 , and notches  224 . The alignment and number of agitator tabs  228  matches a corresponding alignment and number of access channels  226 , circumferential grooves  222 , and notches  224 . 
     The embodiment of  FIGS.  10  through  14    and  FIG.  20    does not include cap  232  within recess  220 . Instead, a user installs agitator post  202  into receptacle  218  by vertically aligning agitator tabs  228  with access channels  226 . Once aligned, agitator post  202  is moved downwardly along vertical axis VA, which results in bottom end  216  making direct contact with biasing element or spring  230  ( FIG.  14   ). As agitator tabs  228  move downwardly along vertical direction V within access channels  226 , tabs  228  eventually reach grooves  222 . The user can then rotate agitator post  202 , which causes agitator tabs  228  to move from first end  262  to second end  264 . 
     Upon reaching second end  264 , the user can release agitator post  202 , which allows biasing element  230  to urge agitator post  202  upwardly. Agitator tabs  228  will move upwardly along vertical direction V until received into notches  224 . This secures the position of agitator post  202  and allows torque from impeller  204  to be transferred to agitator post  202 . The user can remove agitator post  202  by simply reversing the movement just described for installation. Biasing element  230  will urge agitator post  202  upwardly as tabs  228  move upwardly along access channels  226  so that agitator post  202  may be removed from receptacle  218 . 
     Upon removal of agitator post  202 , the user can place a removable cap  242  ( FIG.  11   ) into receptacle  218  ( FIG.  12   ). Removable cap  242  includes a cylindrically-shaped wall  244  that is received into circumferentially-extending slot  240 . A peripheral lip  245  helps cover recess  220  and limit further movement of removable cap  242  downward along vertical direction V. A recess  246  in cap  242  receives spring  230  ( FIG.  12   ). As such, this embodiment of article movement mechanism  200  also allows washing appliance  100  to be used with or without agitator post  202 . When agitator post  202  is not present, removable cap  242  can be used to preclude articles from migrating into recess  220  while also providing improved aesthetics. 
     For previously described embodiments, biasing element  230  is positioned in recess  220  between impeller  204  and agitator post  202 . However, in still another exemplary embodiment of the invention depicted in  FIGS.  15  through  18   , biasing element  230  may be contained within agitator post  202 . This embodiment may still use the access channels  226 , circumferential grooves  222 , and notches  224  as described for the embodiment of  FIGS.  10  through  14    and  FIG.  20   . 
     More particularly, for the embodiment of  FIGS.  15  through  19   , receptacle  218  includes a plurality of grooves  222 , access channels  226 , and notches  224  as previously described in reference to  FIG.  20   . Agitator post  202  again includes agitator tabs  228  ( FIG.  15   ) having a height along vertical direction V and a width along circumferential direction C that allows for sliding movement within access channels  226 , circumferential grooves  222 , and notches  224 . The alignment and number of agitator tabs  228  matches a corresponding alignment and number of access channels  226 , circumferential grooves  222 , and notches  224 . 
     The biasing element or spring  230  is located in a chamber  250  shown in  FIG.  16   . Chamber  250  is formed by bottom end  216  of agitator post  202  and a retainer  248 . In order to allow for compression of spring  230 , retainer  248  is movable along vertical direction V relative to bottom end  216 . 
     A user can install agitator post  202  into receptacle  218  by vertically aligning agitator tabs  228  within access channels  226 . Once aligned, agitator post  202  is moved downwardly along vertical axis VA, which results in retainer  248  contacting receptacle  218  and compressing spring  230 . As agitator tabs  228  move downwardly along vertical direction V within access channels  226 , tabs  228  eventually reach grooves  222 . The user can then rotate agitator post  202 , which causes agitator tabs  228  to move from first end  262  to second end  264 . 
     Upon reaching second end  264 , the user can release agitator post  202 , which allows biasing element  230  to urge agitator post  202  upwardly. Agitator tabs  228  will move upwardly along vertical direction V until received into notches  224 . This secures the position of agitator post  202  and allows torque from impeller  204  to be transferred to agitator post  202 . The user can remove agitator post  202  by simply reversing the movement just described for installation. Spring  230  will urge agitator post  202  upwardly as tabs  228  move upwardly along access channels  226  so that agitator post  202  may be removed from receptacle  218 . Upon removal of agitator post  202 , the user can place removable cap  242  into receptacle  218  as previously described with reference to  FIGS.  11  and  12   . As such, as with previous embodiments, this embodiment of article movement mechanism  200  allows also washing appliance  100  to be used with or without agitator post  202 . When agitator post  202  is not present, removable cap  242  can be used to preclude articles from migrating into recess  220  while also providing improved aesthetics. 
     A different number of tabs, access channels, notches, and grooves may be used from that shown in the figures. Although shown as uniformly spaced along circumferential direction C, different spacings may be used as well. Additionally, the present invention is not limited to the particular shape, size, or configuration of agitator post  202  or impeller  204 —including lobes  206  and vane  210 . While the embodiments shown in the figures would use a clockwise rotation (as viewed downwardly along vertical direction V) to secure agitator post  202  and a counter-clockwise rotation to release it, the features within receptacle  218  may be readily rearranged to provide for an opposite operation to secure or release—as will be understood by one of skill in the art using the teachings disclosed herein. 
     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.