Patent Publication Number: US-10772481-B2

Title: Carrier roller assembly for a rack of a dishwasher appliance

Description:
FIELD OF THE INVENTION 
     The present disclosure relates generally to dishwasher appliances, and more particularly to carrier roller assemblies for supporting the racks of dishwasher appliances. 
     BACKGROUND OF THE INVENTION 
     Dishwasher appliances generally include a tub that defines a wash chamber. Rack assemblies can be mounted within the wash chamber of the tub for receipt of articles for washing. Wash fluid (e.g., various combinations of water and detergent along with optional additives) may be introduced into the tub where it collects in a sump space at the bottom of the wash chamber. During wash and rinse cycles, a pump may be used to circulate wash fluid to spray assemblies within the wash chamber that can apply or direct wash fluid towards articles disposed within the rack assemblies in order to clean such articles. During a drain cycle, a pump may periodically discharge soiled wash fluid that collects in the sump space and the process may be repeated. 
     Conventional dishwasher appliances include slide assemblies for supporting one or upper racks within the wash chamber. These slide assemblies permit a user to slide the upper racks out of the wash chamber for emptying and loading dishes and back into the wash chamber for running a wash cycle. Similarly, typical racks are slidable into and out of the wash chamber between cycles for removing and loading dishes, but rely on roller assemblies to achieve such movement. Particularly, carrier roller assemblies are typically mounted to the rack and include a plurality of rollers that roll along the dishwasher door which opens to a horizontal position. Notably, however, conventional carrier roller assemblies are formed from many parts, require different mold parts for the left and right sides of the rack, and are unable to accommodate racks formed from wires having different sizes. As a result, manufacturing complexity is increased, part procurement and storage is complicated, and appliance assembly is complex and costly. 
     Accordingly, a dishwasher appliance that utilizes an improved carrier roller assembly would be useful. More specifically, a carrier roller assembly that is simple to assemble, versatile, and may be universally used with different wash racks having different wire diameters and on the left and right side of the racks in different model dishwashers would be particularly beneficial. 
     BRIEF DESCRIPTION OF THE INVENTION 
     The present subject matter provides a dishwasher appliance including a carrier roller assembly for supporting a rack within a wash chamber. The carrier roller assembly includes a carrier body defining a receiving slot for receiving a wire of the rack. A first and a second retention clip extend from the carrier body into the receiving slot for securely locking the wire in position after it is fully inserted into the receiving slot. The first retention clip and the second clip are different sizes for snapping around and securing wires having different diameters such that the carrier roller assembly is versatile and may be universally used with dishwasher appliances using differing wire sizes. Additional aspects and advantages of the invention will be set forth in part in the following description, may be apparent from the description, or may be learned through practice of the invention. 
     In accordance with one exemplary embodiment of the present disclosure, a dishwasher appliance defining a vertical, a lateral, and a transverse direction is provided. The dishwasher appliance includes a wash tub that defines a wash chamber for receipt of articles for washing and a rack slidably positioned within the wash chamber and configured for movement along the transverse direction. A door is rotatably mounted to the wash tub for providing selective access to the wash chamber, the door defining a rack rolling surface. A carrier roller assembly supports the rack and includes a carrier body mounted to the rack, the carrier body defining a receiving slot for receiving a wire of the rack, the receiving slot being defined in part by a first wall. A first retention clip extends from the carrier body into the receiving slot, a distal end of the first retention clip being spaced apart from the first wall by a first gap height. A second retention clip extends from the carrier body into the receiving slot, a distal end of the second retention clip being spaced apart from the first wall by a second gap height, the second gap height being smaller than the first gap height. 
     In accordance with another exemplary embodiment of the present disclosure, a carrier roller assembly for supporting a rack within a wash chamber of a dishwasher appliance is provided. The carrier roller assembly includes a carrier body mounted to the rack, the carrier body defining a receiving slot for receiving a wire of the rack, the receiving slot being defined in part by a first wall. A first retention clip extends from the carrier body into the receiving slot, a distal end of the first retention clip being spaced apart from the first wall by a first gap height. A second retention clip extends from the carrier body into the receiving slot, a distal end of the second retention clip being spaced apart from the first wall by a second gap height, the second gap height being smaller than the first gap height. 
     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 an exemplary embodiment of a dishwashing appliance of the present disclosure with a door in a partially open position. 
         FIG. 2  provides a side, cross sectional view of the exemplary dishwashing appliance of  FIG. 1 . 
         FIG. 3  provides an exploded view of a lower rack and carrier roller assemblies according to an example embodiment of the present subject matter. 
         FIG. 4  provides a side view of the exemplary carrier roller assembly of  FIG. 3  mounted on the lower rack according to an example embodiment of the present subject matter. 
         FIG. 5  provides a perspective view of the exemplary carrier roller assembly of  FIG. 3  according to an example embodiment of the present subject matter. 
         FIG. 6  provides a side view of the exemplary carrier roller assembly of  FIG. 3  according to an example embodiment of the present subject matter. 
         FIG. 7  provides a close-up view of retention features of the exemplary carrier roller assembly of  FIG. 3  according to an exemplary embodiment of the subject matter. 
         FIG. 8  provides another close-up view of retention features of the exemplary carrier roller assembly of  FIG. 3  according to an exemplary embodiment of the subject matter. 
     
    
    
     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 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. 
     As used herein, the term “article” may refer to, but need not be limited to dishes, pots, pans, silverware, and other cooking utensils and items that can be cleaned in a dishwashing appliance. The term “wash cycle” is intended to refer to one or more periods of time during which a dishwashing appliance operates while containing the articles to be washed and uses a detergent and water, preferably with agitation, to e.g., remove soil particles including food and other undesirable elements from the articles. The term “rinse cycle” is intended to refer to one or more periods of time during which the dishwashing appliance operates to remove residual soil, detergents, and other undesirable elements that were retained by the articles after completion of the wash cycle. The term “drain cycle” is intended to refer to one or more periods of time during which the dishwashing appliance operates to discharge soiled water from the dishwashing appliance. The term “wash fluid” refers to a liquid used for washing and/or rinsing the articles and is typically made up of water that may include other additives such as detergent or other treatments. Furthermore, as used herein, terms of approximation, such as “approximately,” “substantially,” or “about,” refer to being within a ten percent margin of error. 
       FIGS. 1 and 2  depict an exemplary domestic dishwasher or dishwashing appliance  100  that may be configured in accordance with aspects of the present disclosure. For the particular embodiment of  FIGS. 1 and 2 , the dishwasher  100  includes a cabinet  102  ( FIG. 2 ) having a tub  104  therein that defines a wash chamber  106 . As shown in  FIG. 2 , tub  104  extends between a top  107  and a bottom  108  along a vertical direction V, between a pair of side walls  110  along a lateral direction L, and between a front side  111  and a rear side  112  along a transverse direction T. Each of the vertical direction V, lateral direction L, and transverse direction T are mutually perpendicular to one another. 
     The tub  104  includes a front opening  114  and a door  116  hinged at its bottom for movement between a normally closed vertical position (shown in  FIG. 2 ), wherein the wash chamber  106  is sealed shut for washing operation, and a horizontal open position for loading and unloading of articles from the dishwasher  100 . According to exemplary embodiments, dishwasher  100  further includes a door closure mechanism or assembly  118  that is used to lock and unlock door  116  for accessing and sealing wash chamber  106 . 
     As best illustrated in  FIG. 2 , tub side walls  110  accommodate a plurality of rack assemblies. More specifically, a lower rack assembly  122 , a middle rack assembly  124 , and an upper rack assembly  126  are stacked along the vertical direction V within wash chamber  106 . Each rack assembly  122 ,  124 ,  126  is adapted for movement between an extended loading position (not shown) in which the rack is substantially positioned outside the wash chamber  106 , and a retracted position (shown in  FIGS. 1 and 2 ) in which the rack is located inside the wash chamber  106 . With respect to middle rack assembly  124  and upper rack assembly  126 , this is facilitated, for example, by guide rails  120  which are mounted to side walls  110  and rollers  128  mounted onto rack assemblies  124 ,  126 , respectively. In addition, as will be described in more detail below, lower rack assembly  122  (or any other rack assembly) may include a plurality of carrier roller assemblies  200  which slidably support lower rack assembly  122 , thereby permitting the lower rack to roll out of wash chamber  106  and rest on door  116  when it is in the open (i.e., horizontal) position. Although a guide rails  120 , rollers  128 , and carrier roller assemblies  200  are illustrated herein as facilitating movement of the respective rack assemblies  122 ,  124 ,  126 , it should be appreciated that any suitable sliding mechanism or member may be used according to alternative embodiments. 
     Some or all of the rack assemblies  122 ,  124 ,  126  are fabricated into lattice structures including a plurality of wires or elongated members  130  (for clarity of illustration, not all elongated members making up rack assemblies  122 ,  124 ,  126  are shown in  FIG. 2 ). In this regard, rack assemblies  122 ,  124 ,  126  are generally configured for supporting articles within wash chamber  106  while allowing a flow of wash fluid to reach and impinge on those articles, e.g., during a cleaning or rinsing cycle. According to another exemplary embodiment, a silverware basket (not shown) may be removably attached to a rack assembly, e.g., lower rack assembly  122 , for placement of silverware, utensils, and the like, that are otherwise too small to be accommodated by rack  122 . 
     Dishwasher  100  further includes a plurality of spray assemblies for urging a flow of water or wash fluid onto the articles placed within wash chamber  106 . More specifically, as illustrated in  FIG. 2 , dishwasher  100  includes a lower spray arm assembly  134  disposed in a lower region  136  of wash chamber  106  and above a sump  138  so as to rotate in relatively close proximity to lower rack assembly  122 . Similarly, a mid-level spray arm assembly  140  is located in an upper region of wash chamber  106  and may be located below and in close proximity to middle rack assembly  124 . In this regard, mid-level spray arm assembly  140  may generally be configured for urging a flow of wash fluid up through middle rack assembly  124  and upper rack assembly  126 . Additionally, an upper spray assembly  142  may be located above upper rack assembly  126  along the vertical direction V. In this manner, upper spray assembly  142  may be configured for urging and/or cascading a flow of wash fluid downward over rack assemblies  122 ,  124 , and  126 . As further illustrated in  FIG. 2 , upper rack assembly  126  may further define an integral spray manifold  144 , which is generally configured for urging a flow of wash fluid substantially upward along the vertical direction V through upper rack assembly  126 . 
     The various spray assemblies and manifolds described herein may be part of a fluid distribution system or fluid circulation assembly  150  for circulating water and wash fluid in the tub  104 . More specifically, fluid circulation assembly  150  includes a pump  152  for circulating water and wash fluid (e.g., detergent, water, and/or rinse aid) in the tub  104 . Pump  152  may be located within sump  138  or within a machinery compartment located below sump  138  of tub  104 , as generally recognized in the art. Fluid circulation assembly  150  may include one or more fluid conduits or circulation piping for directing water and/or wash fluid from pump  152  to the various spray assemblies and manifolds. For example, as illustrated in  FIG. 2 , a primary supply conduit  154  may extend from pump  152 , along rear  112  of tub  104  along the vertical direction V to supply wash fluid throughout wash chamber  106 . 
     As illustrated, primary supply conduit  154  is used to supply wash fluid to one or more spray assemblies, e.g., to mid-level spray arm assembly  140  and upper spray assembly  142 . However, it should be appreciated that according to alternative embodiments, any other suitable plumbing configuration may be used to supply wash fluid throughout the various spray manifolds and assemblies described herein. For example, according to another exemplary embodiment, primary supply conduit  154  could be used to provide wash fluid to mid-level spray arm assembly  140  and a dedicated secondary supply conduit (not shown) could be utilized to provide wash fluid to upper spray assembly  142 . Other plumbing configurations may be used for providing wash fluid to the various spray devices and manifolds at any location within dishwasher appliance  100 . 
     Each spray arm assembly  134 ,  140 ,  142 , integral spray manifold  144 , or other spray device may include an arrangement of discharge ports or orifices for directing wash fluid received from pump  152  onto dishes or other articles located in wash chamber  106 . The arrangement of the discharge ports, also referred to as jets, apertures, or orifices, may provide a rotational force by virtue of wash fluid flowing through the discharge ports. Alternatively, spray arm assemblies  134 ,  140 ,  142  may be motor-driven, or may operate using any other suitable drive mechanism. Spray manifolds and assemblies may also be stationary. The resultant movement of the spray arm assemblies  134 ,  140 ,  142  and the spray from fixed manifolds provides coverage of dishes and other dishwasher contents with a washing spray. Other configurations of spray assemblies may be used as well. For example, dishwasher  100  may have additional spray assemblies for cleaning silverware, for scouring casserole dishes, for spraying pots and pans, for cleaning bottles, etc. One skilled in the art will appreciate that the embodiments discussed herein are used for the purpose of explanation only, and are not limitations of the present subject matter. 
     In operation, pump  152  draws wash fluid in from sump  138  and pumps it to a diverter assembly  156 , e.g., which is positioned within sump  138  of dishwasher appliance. Diverter assembly  156  may include a diverter disk (not shown) disposed within a diverter chamber  158  for selectively distributing the wash fluid to the spray arm assemblies  134 ,  140 ,  142  and/or other spray manifolds or devices. For example, the diverter disk may have a plurality of apertures that are configured to align with one or more outlet ports (not shown) at the top of diverter chamber  158 . In this manner, the diverter disk may be selectively rotated to provide wash fluid to the desired spray device. 
     According to an exemplary embodiment, diverter assembly  156  is configured for selectively distributing the flow of wash fluid from pump  152  to various fluid supply conduits, only some of which are illustrated in  FIG. 2  for clarity. More specifically, diverter assembly  156  may include four outlet ports (not shown) for supplying wash fluid to a first conduit for rotating lower spray arm assembly  134 , a second conduit for rotating mid-level spray arm assembly  140 , a third conduit for spraying upper spray assembly  142 , and a fourth conduit for spraying an auxiliary rack such as the silverware rack. 
     The dishwasher  100  is further equipped with a controller  160  to regulate operation of the dishwasher  100 . The controller  160  may include one or more memory devices and one or more microprocessors, such as general or special purpose microprocessors 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  160  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. 
     The controller  160  may be positioned in a variety of locations throughout dishwasher  100 . In the illustrated embodiment, the controller  160  may be located within a control panel area  162  of door  116  as shown in  FIGS. 1 and 2 . In such an embodiment, input/output (“I/O”) signals may be routed between the control system and various operational components of dishwasher  100  along wiring harnesses that may be routed through the bottom of door  116 . Typically, the controller  160  includes a user interface panel/controls  164  through which a user may select various operational features and modes and monitor progress of the dishwasher  100 . In one embodiment, the user interface  164  may represent a general purpose I/O (“GPIO”) device or functional block. In one embodiment, the user interface  164  may include input components, such as one or more of a variety of electrical, mechanical or electro-mechanical input devices including rotary dials, push buttons, and touch pads. The user interface  164  may include a display component, such as a digital or analog display device designed to provide operational feedback to a user. The user interface  164  may be in communication with the controller  160  via one or more signal lines or shared communication busses. 
     It should be appreciated that the invention is not limited to any particular style, model, or configuration of dishwasher  100 . The exemplary embodiment depicted in  FIGS. 1 and 2  is for illustrative purposes only. For example, different locations may be provided for user interface  164 , different configurations may be provided for rack assemblies  122 ,  124 ,  126 , different spray arm assemblies  134 ,  140 ,  142  and spray manifold configurations may be used, and other differences may be applied while remaining within the scope of the present subject matter. 
     Referring now generally to  FIGS. 3 through 6 , a lower rack and carrier roller assembly  200  will be described according to an example embodiment of the present subject matter. Carrier roller assembly  200  may be used as shown in  FIG. 2  for supporting lower rack assembly  122 . Carrier roller assembly  200  is generally configured for providing vertical support to a lower rack  202 , which may be equivalent to lower rack assembly  122 . In addition, as shown in the exemplary embodiment illustrated in  FIG. 2 , tub  104  of dishwasher  100  may define lower guide rails  204  and door  116  may define a lower rack rolling surface  206 . In this manner, when door  116  is in the open position such that it extends substantially within a horizontal plane, carrier roller assembly  200  may permit lower rack  202  slide out of wash chamber  106  along the transverse direction T and rest on door  116  for loading and unloading dishes. Although carrier roller assembly  200  is illustrated as being used to support lower rack  202 , it should be appreciated that carrier roller assembly  200  may be used with any suitable dishwasher rack. 
     As best shown in  FIG. 3 , lower rack  202  may be supported by four carrier roller assemblies  200 . In this regard, two carrier roller assemblies  200  may be positioned on each lateral side of lower rack  202 . Moreover, as described below, carrier roller assemblies  200  are designed to be interchangeably used on either the left side or the right side of lower rack  202 . In this manner, a single set of molds may be used to form the left and right side carrier roller assemblies  200 , thereby reducing manufacturing costs and complexity. Notably, when carrier roller assembly  200  is installed onto lower rack  202 , carrier roller assembly  200  shares a coordinate system with dishwasher  100 . Therefore, carrier roller assembly  200  will be described in herein as sharing the vertical direction V, the lateral direction L, and the transverse direction T with dishwasher  100 . 
     Referring now to  FIGS. 4 through 6 , carrier roller assembly  200  includes a carrier body  210  that is mounted to lower rack  202  and defines a plurality of roller mounts  212 . More specifically, according to the illustrated embodiment, carrier body  210  defines two roller mounts  212  that are spaced apart along the transverse direction T and extend along the lateral direction L. Carrier roller assembly  200  further includes a plurality of rollers  214  that are rotatably mounted onto the plurality of roller mounts  212 . In this regard, rollers  214  may define a cylindrical channel that is received over roller mounts  212  may be secured in place using a pin or another latching feature, such as a resilient clip  216 . Therefore, when rollers  214  are mounted onto roller mounts  212 , and when carrier body  210  is fixed to lower rack  202 , lower rack  202  may roll into and out of wash chamber  106 , e.g., along lower guide rails  204  and lower rack rolling surface  206 . 
     As illustrated, carrier body  210  also defines a receiving slot  220  that is generally configured for receiving a wire  222  of lower rack  202 . More specifically, receiving slot  220  extends through carrier body  210  and is defined at least in part by a first wall  224 , a second wall  226 , and an end wall  228 . In general, carrier roller assembly  200  is mounted on lower rack  202  by sliding carrier body  210  onto lower rack  202  such that wire  222  is received within receiving slot  220 . According to the illustrated embodiment, receiving slot  220  is defined proximate a top surface  230  of carrier body  210 . More specifically, receiving slot  220  extends from an entry  232  defined in top surface  230  and extends at least partially within the horizontal plane (i.e., as defined by the lateral direction L and transverse direction T) within carrier body  210 . In order to further stabilize carrier roller assembly  200 , carrier body  210  may further define a secondary slot  234  that is spaced apart from receiving slot  220  along the transverse direction T. Secondary slot  234  may have the same or a similar shape to receiving slot  220  and may be configured for receiving an adjacent wire  222  of lower rack  202 . 
     The various components of carrier roller assembly  200  may be formed from any suitable material and in any suitable manner. For example, according to an exemplary embodiment, carrier body  210  is injection molded as a single piece using a suitably rigid plastic material. Similarly, rollers  214  are injection molded from plastic and snapped onto carrier body  210  to complete carrier roller assembly  200 . Notably, such a construction reduces the number of parts necessary to assemble lower rack assembly  122  thereby reducing manufacturing time, costs, and complexity. 
     In order to secure carrier roller assembly  200  onto lower rack  202 , carrier body  210  defines various features for locking lower rack  202 , or more specifically wires  222 , into carrier body  210 . More specifically, according to an exemplary embodiment, carrier roller assembly  200  includes a first retention clip  240  and a second retention clip  242  that extend from carrier body  210  into receiving slot  220 . In general, retention clips  240 ,  242  are resilient members configured for engaging and locking wire  222  in position at a bottom of receiving slot  220 , i.e., where wire  222  is contacting end wall  228 . 
     According to the illustrated embodiment, first retention clip  240  and second retention  242  are each flexible arms have a fixed end  244  positioned proximate entry  232  of receiving slot  220  and a distal end  246  that extends toward end wall  228  in a cantilevered manner. More specifically, an aperture  248  is defined through top surface  230  of carrier body  210  (i.e., through second wall  226 ). Retention clips  240 ,  242  extend from carrier body within aperture  248  and protrude down into receiving slot  220 . In this manner, retention clips  240 ,  242  may deflect when wire  222  is pressed into receiving slot  220  until wire  222  clears retention clips  240 ,  242  which may then snap back into a relaxed position for preventing the subsequent removal of wire  222  from receiving slot  220 . 
     Referring now to  FIGS. 7 and 8 , retention clips  240 ,  242  have a size and geometry for securing wires  222  having different diameters. In this regard, for example, distal end  246  of first retention clip  240  may be spaced apart from end wall  228  by a first distance  250  along the transverse direction T. Similarly, distal end  246  of second retention clip  242  may be spaced apart from end wall  228  by a second distance  252  along the transverse direction T. As illustrated, second distance  252  is smaller than the first distance  250 . In this manner, if wire  222  has a diameter that is less than or substantially equal to first distance  250 , first retention clip  240  will secure and lock wire  222  in place when pressed fully into receiving slot  220  (i.e., such that wire  222  contacts end wall  228 ). Similarly, if wire  222  has a diameter that is less than or substantially equal to second distance  252 , second retention clip  242  will secure and lock wire  222  within receiving slot  220 , while first retention clip  240  remains disengaged from wire  222 . 
     As best shown in  FIG. 8 , receiving slot  220  further defines a slot height  260  between first wall  224  and second wall  226  along the vertical direction V. according to the illustrated embodiment slot height  260  is substantially equivalent to first distance  250  such that any wire  222  having a diameter less than or equal to first distance  250  may be received within receiving slot  220 . In addition, retention clips  240 ,  242  both extend into receiving slot  220  along the vertical direction V to define a gap height between first wall  224  and each respective retention clip  240 ,  242 . More specifically, according to the illustrated exemplary embodiment, first retention clip  240  protrudes into receiving slot  220  to define a first gap height  262 , which according to an exemplary embodiment is equal to about half of slot height  260 . Similarly second retention clip  242  protrudes into receiving slot  220  to define a second gap height  264  which is less than the first gap height  262 . 
     It should be appreciated that retention clips  240 ,  242  and receiving slot  220  are described above according to an exemplary embodiment to explain aspects of the present subject matter. It should be appreciated that the size and geometry of these features may be changed according to alternative embodiments. For example, the size, resiliency, and geometry of retention clips  240 ,  242  may be altered to accommodate wires  222  having different sizes. In addition, the lengths of retention clips  240 ,  242 , the gap height and the gap distances defined within receiving slot  220  may be altered depending on the resiliency of retention clips  240 ,  242  and the size of wire  222 . According to still another embodiment, each retention clip may define a stiffening rib  266  that extend along the transverse direction T on each clip to provide additional rigidity. Other configurations of retention clips  240 ,  242  are possible and within the scope of the present subject matter. 
     By defining carrier body  210  and retention clips  240 ,  242  as described above, carrier roller assembly  200  may be used in dishwasher appliances having lower racks formed from different types of wire. In this regard, for example, a typical wire  222  that is formed from polyvinyl chloride (PVC) may have a maximum diameter of approximately 0.18 inches. By contrast, a typical wire  222  that is formed from nylon may have a maximum diameter of approximately 0.17 inches. According to alternative embodiments, typical wire  222  may have any other suitable size, such as between 0.15 and 0.19 inches. Notably, retention clips  240 ,  242  may define first distance  250  and second distance  252  to be approximately 0.18 and 0.17 inches, respectively, to enable carrier roller assembly  200  to be used to support lower racks formed from either PVC or nylon wires. As described above, carrier body  210  defines two retention clips  240 ,  242  which may be used for mounting carrier roller assembly  200  to lower racks formed from wires having two different diameters. However, it should be appreciated that according to alternative embodiments, carrier body  210  may define any suitable number retention clips for securing any suitable size wire  222 , being constructed of any material and having any suitable type and thickness of coating. 
     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 language of the claims.