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CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a divisional of U.S. patent application Ser. No. 10/540,006 filed on Nov. 14, 2006, which is a National Stage of International Application No. PCT/US2003/038021 filed on Nov. 26, 2003, which claims the benefit of U.S. Provisional Application No. 60/430,130 filed on Nov. 30, 2002. The entire disclosures of each of the above applications are incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to waste management systems. More particularly, the present invention relates to a flush toilet. More specifically, but without restriction to the particular embodiment and/or use which is shown and described for purposes of illustration, the present invention pertains to a reduced water consumption flush toilet. 
       BACKGROUND OF THE INVENTION 
       [0003]    Vehicles including recreational vehicles (“RVs”), airplanes, boats, trains, and the like often include toilets for the comfort and convenience of the passengers. The toilets of vehicles must perform under operating conditions that are significantly different from non-transitory toilets conventionally found in homes and businesses (“home toilets”). For example, vehicle toilets are typically required to operate often in a confined area. Additionally, vehicle toilets rely on a source of on-board water for flushing. For the latter reason, vehicle toilets are typically designed to operate with reduced water consumption for water conservation. 
         [0004]    The design of vehicle toilets must accommodate the distinct operating conditions and preferably provide the customer with the comforts and customary features associated with home toilets. One example of a vehicle toilet is shown and described in commonly assigned U.S. Pat. No. 5,060,320 which is hereby incorporated by reference as if fully set forth herein. U.S. Pat. No. 5,060,320 discloses a toilet having a foot pedal flush control arrangement including two pedals. One of the pedals opens a toilet bowl discharge outlet and the other pedal supplies flush water to the bowl. The pedals both operate through actuation cables having a wire member slidable within a conduit. The flush water pedal can be independently actuated to partially fill the bowl prior to use of the toilet while the outlet closure member pedal co-acts with the flush water pedal so that upon opening of the bowl outlet, the flush water pedal is depressed providing water to the bowl. The wire members are solid wire members coupled to the pedals for both pull and push operation so that upon a failure of the pedal return mechanism, the pedals can be manually returned closing the bowl outlet and terminating the flow of flush water to the bowl. 
         [0005]    While known vehicle toilets, including the toilet disclosed by U.S. Pat. No. 5,060,320, have proven acceptable for their intended applications, there remains a need for continuous improvement in the pertinent art. 
       SUMMARY OF THE INVENTION 
       [0006]    It is an object of the present invention to provide flush toilet for a motor vehicle that has a ball valve for selectively opening and closing a discharge opening of a bowl assembly that is driven by a flexible a cable. 
         [0007]    It is another object of the present invention to provide a flush toilet for a motor vehicle that includes a china bowl and a plastic shroud that allows for easy mounting of the bowl to the base. 
         [0008]    It is another object of the present invention to provide a flush toilet for a motor vehicle having a china bowl and a plastic shroud that reduces the weight of the flush toilet. 
         [0009]    It is a related object of the present invention to provide a flush toilet with a china bowl and a plastic shroud with improved cleanability. 
         [0010]    It is another object of the present invention to provide a flush toilet system having a common base and a plastic shroud that provides for an aesthetically pleasing product. 
         [0011]    It is another object of the present invention to provide a flush toilet with a shroud for attachment to a china bowl that is easily removed after original installation for cleaning and service. 
         [0012]    It is another object of the present invention to provide a flush toilet having a single sealing member that performs the dual functions of sealing a vitreous china bowl to a plastic base and sealing at a waste ball valve. 
         [0013]    It is another object of the present invention to provide a flush toilet with a quality flush with a limited amount of water pressure and volume. 
         [0014]    In one form, the present invention provides a flush toilet for a motor vehicle having a bowl assembly, a waste ball valve assembly and a water valve assembly. The bowl assembly defines a bowl and a discharge opening at a lower end of the bowl. The waste ball valve assembly is mounted to the flush toilet for selectively opening and closing the discharge opening of the bowl assembly. The water valve assembly delivers a source of flush water to the bowl. The water valve assembly includes a water valve operable in a water valve open condition and a water valve closed condition. The flush toilet further includes a common actuator for controlling both the waste ball valve assembly and the water valve assembly. The common actuator is movable from a first position to an intermediate position and from the intermediate position. In the first position the waste ball valve assembly closes the discharge opening and the water valve assembly is in the closed condition. In the intermediate position the waste ball valve assembly closes the discharge opening and the water valve assembly is in the open position for adding water to the bowl. In the second position the waste ball valve assembly opens the discharge opening and the water valve assembly is in the open position for flushing the bowl. 
         [0015]    In another form, the present invention provides a flush toilet for a motor vehicle having a bowl assembly, a waste ball valve assembly and a water valve assembly. The bowl assembly defines a bowl and a discharge opening at a lower end of the bowl. The waste ball valve assembly is mounted to the flush toilet for selectively opening and closing the discharge opening of the bowl assembly. The water valve assembly selectively delivers a source of flush water to the bowl. The water valve assembly includes a water valve operable in a water valve open condition and a water valve closed condition. An actuator controls the waste ball valve assembly and is interconnected to the waste ball valve assembly by a flexible cable. The actuator is movable from a first position to second position for selectively opening the discharge opening. 
         [0016]    In another form, the present invention provides a reduced water consumption flush toilet including a bowl assembly defining a bowl having a discharge outlet at a lower end and a ledge circumferentially extending about a substantial portion of the bowl. The flush toilet includes a nozzle mounted to the bowl assembly for pressurizing a source of flush water and delivering the source of flush water to the bowl for rinsing and flushing of the bowl. The nozzle is positioned at a rear portion of the bowl and operatives to produce a first flow of water in a first circumferential direction about the bowl and a second flow of water in a second circumferential direction about the bowl, the second circumferential direction being opposite to the first circumferential direction. The ledge cascades the first and second flows of flush water down the bowl as the first and second flows of water move in the first and second circumferential directions, respectively. 
         [0017]    In yet another form, the present invention provides a flush toilet including a base and a bowl assembly defining a bowl. The bowl assembly is mounted to the base and defines a discharge opening at a lower end of the bowl. A waste ball valve assembly is mounted to the flush toilet for selectively opening and closing the discharge opening of the bowl assembly. A common sealing member seals the bowl to the base and wipes a ball of the ball valve assembly as the waste ball valve assembly is selectively opened and closed. 
         [0018]    In still yet another form, the present invention provides a flush toilet including a bowl assembly defining a bowl, a base downwardly extending from the bowl assembly and a shroud removable attached to the toilet. The shroud peripherally surrounding at least a portion of the bowl assembly or at least a portion of the base. 
         [0019]    Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]    The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
           [0021]      FIG. 1  is a front perspective view of a flush toilet constructed in accordance with the teachings of a first preferred embodiment of the present invention. 
           [0022]      FIG. 2  is a rear perspective view of the flush toilet of  FIG. 1  shown partially exploded. 
           [0023]      FIG. 3  is a cross-sectional view taken along the line  3 - 3  of  FIG. 1 . 
           [0024]      FIG. 4  is a cross-sectional view taken along the line  4 - 4  of  FIG. 3 . 
           [0025]      FIG. 5  is a cross-sectional view taken along the line  5 - 5  of  FIG. 3 . 
           [0026]      FIGS. 6A-6C  represent a series of views of the base of the flush toilet of  FIG. 1  illustrating the water valve drive arm as it rotates from a closed position ( FIG. 6A ), to a water-add position ( FIG. 6B ), and to a flush position ( FIG. 6C ). 
           [0027]      FIG. 7  is an enlarged front view of the nozzle of the flush toilet of  FIG. 1  illustrating flow from the nozzle. 
           [0028]      FIG. 8  is a perspective view of the flush arrangement of the flush toilet of  FIG. 1 . 
           [0029]      FIG. 9  is an exploded perspective view illustrating the waste valve assembly and the waste valve drive arm of the flush arrangement of the flush toilet of  FIG. 1 . 
           [0030]      FIG. 10  is an exploded perspective view of the water valve drive arm of the flush arrangement of the flush toilet of  FIG. 1 . 
           [0031]      FIGS. 11A and 11B  are cross-section views of the water valve assembly of the flush toilet of  FIG. 1 , illustrating the water valve assembly in an open condition and a closed condition, respectively. 
           [0032]      FIG. 12  is an alternative flush arrangement of the flush toilet of  FIG. 1 . 
           [0033]      FIG. 13  is a perspective view of a seal member and seal retainer of the flush toilet of  FIG. 1 . 
           [0034]      FIG. 14  is a front perspective view of a flush toilet constructed in accordance with the teachings of a second embodiment of the present invention. 
           [0035]      FIG. 15  is a top view of the flush toilet of  FIG. 1  shown with the seat and lid removed for purposes of illustration. 
           [0036]      FIG. 16  is a cross-sectional view taken along the line  16 - 16  of  FIG. 15 . 
           [0037]      FIG. 17  is a cross-sectional view taken along the line  17 - 17  of  FIG. 15 . 
           [0038]      FIG. 18  is a rear perspective view of the flush toilet of  FIG. 14  shown partially exploded. 
           [0039]      FIG. 19  is a front view of the nozzle of the flush toilet of  FIG. 14 . 
           [0040]      FIG. 20  is an exploded, rear perspective view of the nozzle of the flush toilet of  FIG. 14 . 
           [0041]      FIG. 21  is a view similar to  FIG. 15  illustrating the flow characteristics of the nozzle of  FIGS. 19 and 20 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0042]    The following description of the preferred apparatus of the present invention is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
         [0043]    With reference to  FIGS. 1-13  of the drawings, a flush toilet constructed according to the teachings of a first embodiment of the present invention is illustrated and generally identified at reference character  10 . In one particular application, the flush toilet  10  is intended for use within a motor vehicle such as a recreational vehicle or the like. After a reading of the remainder of this detailed description, however, those skilled in the art will readily appreciate that the teachings of the present invention are not limited to this exemplary application. Rather, various of the teachings of the present invention have applicability to other vehicle and non-vehicle applications. 
         [0044]    The flush toilet  10  of the present invention is illustrated as what is known as a high rise toilet and is generally shown to include a bowl assembly  12  and a base or housing  14 . Alternatively, the flush toilet  10  can be constructed as a low rise toilet that is mounted on a platform. The bowl assembly  12  is constructed of a vitreous china. The base  14  is constructed of a plastic. As will be addressed below, a shroud or shroud  16  surrounds the base  14  and provides an improved aesthetic appearance for the toilet  10 . 
         [0045]    With particular reference to the cross-sectional views of  FIGS. 3 through 5 , the geometry of the bowl assembly  12  insofar as it relates to the present invention will be described. As will become more apparent below, the bowl assembly  12  has a unique geometry that cooperates with a nozzle  32  to provide for improved rinsing and flushing. The toilet  10  of the present invention is particularly intended, but not exclusively limited for motor vehicle applications. Such applications are expected to receive a wide range of incoming water pressures depending on the particular source of flush water. In the particular embodiment illustrated, the pressure of the incoming flush water is not dynamically controlled. It is important that the bowl geometry and the nozzle  32  cooperatively function to provide an adequate rinse and flush at lower water pressures and also cooperatively function to prevent water from splashing from the toilet  10  at higher water pressures. 
         [0046]    The bowl assembly  12  is shown to include at its lower end a discharge outlet  20  defined by a downwardly projecting portion  22 . The upper end of the bowl assembly  12  is open to define a bowl  24 . A lower end of the bowl assembly is mounted to the base  14 . The bowl assembly  12  is bolted or otherwise securely fastened to the base  14  in any manner well known in the art. 
         [0047]    The bowl assembly  12  of the flush toilet  10  is constructed to include a rim  26  and a ledge  27 . The rim  26  includes an upper surface  28  and a downwardly extending flange  30 . The rim  26  provides protection against splashing of water outside of the unit and provides a more “home-like” appearance. In the embodiment illustrated, the rim  26  is a separately constructed piece that is bonded to a lower portion of the bowl assembly  12 . 
         [0048]    The ledge  27  of the bowl assembly  12  is shown most clearly in  FIGS. 3 and 4 . The bowl  24  defines a generally flat and generally vertical surface  29  (see  FIG. 3 , for example) immediately adjacent the nozzle  32 . This generally vertical surface  29  transitions into the ledge  27  as the bowl  24  continues in both a clockwise and a counterclockwise direction. Reference to clockwise and counterclockwise directions will be understood to be in relationship to the top view of  FIG. 4 . The horizontal width of the ledge  27  increases as the ledge continues from the generally vertical surface  29  to the front of the bowl  24 . The angle of the ledge  27  increases as the ledge continues from adjacent the generally vertical surface  29  to the front of the bowl  24 . In this regard, the maximum slope of the ledge  27  is located at the front of the bowl  24 . 
         [0049]    In a manner to be discussed more fully below, the nozzle  32  provides a source of flush water and is positioned below the rim  26 . The nozzle  32  includes a plurality of holes that cooperates with the rim  26  and the ledge  27  to create an improved flushing or rinsing action by distributing flush water around the rim  26 . The symbiotic relationship between the ledge  27  and the nozzle pattern provides improved rinsing and flushing action for low water consumption applications. 
         [0050]    With continued reference to the cross-sectional views of  FIGS. 3 through 5  and additional reference to the exploded view of  FIG. 8 , a flush arrangement  40  of the flush toilet  10  of the present invention will be described. In the embodiment illustrated, the flush arrangement  40  is controlled by a single actuator. In the embodiment illustrated, the actuator is a foot actuated lever  42 . 
         [0051]    The foot actuated lever  42  is movable from a first position (as shown in  FIGS. 1 and 3 , for example) to a second position (identified in the drawings in simple phantom lines in  FIG. 3  at reference character  42 ″) downwardly pivoted about 25° from the first position. As will be more further discussed below, articulation of the lever  42  from the first position to an intermediate position functions to add water to the bowl  24  without opening the discharge opening  20 . The intermediate position is identified in the drawings in simple phantom lines in  FIG. 3  at reference character  42 ′. Continued articulation from the intermediate position to the second position functions to selectively open the discharge opening  20  of the bowl assembly  12  and functions to selectively deliver a source of flush water to the bowl  24  of the bowl assembly  12  for flushing. It will be appreciated by those skilled in that art that various teachings of the present invention may alternatively be employed with a hand actuated lever or an electronically controlled arrangement. 
         [0052]    The flush arrangement  40  is illustrated to generally include a waste ball valve assembly  44  and a water valve assembly  46 . In a manner to be discussed, the waste ball valve assembly  44  is operative to selectively open and close the discharge opening  20  of the bowl assembly  12 . The water valve assembly  46  is operative for selectively delivering a source of flush water to the bowl  24  for rinsing and flushing. 
         [0053]    As will become more apparent below, the flush arrangement  40  of the flush toilet  10  allows the foot actuated lever  42  to be conveniently positioned at the front of the flush toilet  10  and the water valve assembly  46  to be positioned at the rear of the flush toilet  10 . The waste valve assembly  44  includes a central portion  44  and first and second ends  50  and  52 . The central portion  48  is spherical in shape and in a manner to become more apparent below cooperates with a seal member  54  for selectively opening and closing the discharge opening  20 . The first and second ends  50  and  52  of the waste valve assembly  44  are generally cylindrical in shape and are rotatably received in cooperating cylindrical apertures defined by the housing  14 . As such, the central portion  48  is rotatable between open and closed positions about an axis extending through the first and second cylindrical ends  50  and  52 . 
         [0054]    Opening and closing of the water valve assembly  46  is controlled by a water valve drive arm  58 . The water valve drive arm  58  is rotatably mounted to the housing  14  and includes a main body portion  59  and a valve member  60 . A snap ring  61  and an O-ring  63  are positioned between the main body  59  and the valve member  60 . In this regard, a splined extension  65  of the main body  59  passes through the snap ring  61  and the O-ring  63  and engages an aperture of the valve member  60 . 
         [0055]    As shown in  FIGS. 11A and 11B , the valve member  60  extends into the water valve assembly  46  and functions to selectively open and close a water path for the delivery of flush water to the bowl  24 .  FIG. 11A  illustrates the valve member  60  rotated to a first position in which the water valve assembly  46  is in an open condition.  FIG. 11B  illustrates the valve member  60  rotated to a second position in which the water valve assembly is in a closed condition. In the open condition, flush water passes through the water valve assembly  46  to a breaker assembly  62  and in turn to the nozzle  32 . 
         [0056]    The water valve drive arm  58  is connected to the foot actuated lever  42  by a flexible cable  64 . The cable  64  provides flexibility for relative positioning of the lever  42  and the remainder of the flush arrangement  40 . In this regard, prior art arrangements incorporating a ball valve require the actuating member and the ball valve to rotate about parallel (if no coincident) axes. As such, conventional placement of the lever and flush arrangement has been limited. 
         [0057]    A first end of the cable  64  is coupled to the foot actuated lever  42  (see  FIG. 5 ). A second end of the cable  64  is coupled to the water valve drive arm  58  (see  FIG. 8 , for example). When the foot actuated lever  42  is rotated from the first position to the intermediate position, the water valve drive arm  58  is rotated through approximately 5-10 degrees. This initial rotation of the water valve drive arm  58  is shown in  FIG. 6B , for example, and rotates the valve member  60  to open the water valve assembly  46  for adding water to the bowl  24 . 
         [0058]    The waste valve assembly  44  is driven by a waste valve drive arm  68 . The waste valve drive arm  68  is mounted to the waste valve assembly  44  by a fastener  70  for common rotation. The fastener  70  engages an aperture  71  in the end  52 . The second end  52  and waste valve drive arm  68  are provided with cooperating structure to prevent relative rotation therebetween. 
         [0059]    The waste valve drive arm  68  is coupled to the water valve drive arm  58  through a lost motion connection. More particularly in this regard, the waste valve drive arm  68  is connected to the water valve drive arm  58  by a link  72 . A first end of the link  72  is received by an aperture  73  of the water valve drive arm  58 . A second end of the link  72  is slidably received within a slot  74  defined by the waste valve drive arm  68 . When the foot actuated lever  42  is rotated from the first position to the intermediate position, the second end of the link  72  transitions from one end of the slot  74  to the other end of the slot without rotating the waste valve drive arm  68 . When the foot actuated lever  42  is rotated from the intermediate position to the second position, continued rotation of the water valve drive arm  58  causes corresponding rotation of the waste valve drive arm  68 . This rotation of the waste valve drive arm  68  in turn rotates the waste valve assembly  44  for opening of the discharge opening  20 . In this position, the water valve assembly  46  remains open for delivering the source of flush water to the bowl  24  for flushing of the bowl  24 . 
         [0060]    Turning now to the perspective view of  FIG. 12 , an alternative flush assembly of the present invention is illustrated and generally identified at reference character  80 . Various components are also common between the flush assemblies. For this reason, like reference numbers are used with reference to  FIG. 12  to denote like components previously discussed. The alternative flush assembly of  FIG. 12  again includes a waste valve assembly  44  having a central portion  48  that is partially spherical in shape and is mounted to the base  14  for rotation about an axis. The waste valve assembly  44  rotates in a direction A from a waste valve open position (as shown in  FIG. 12 ) to a waste valve closed position (not specifically shown). 
         [0061]    A first end  50  of the waste valve assembly  44  is coupled to an input shaft  84 . An end of the input shaft  84  is coupled to the foot actuated lever  42  through a camming member  86 . The camming member  86  converts approximately 25 degrees of lever  42  articulation to approximately 105 degrees of waste valve assembly  44  rotation. Through this rotation, the waste valve assembly  44  is articulated between its closed and open positions. A spring  88  functions to bias the waste valve assembly  44  to its closed position and also functions to bias the lever  42  to its first or upper position. 
         [0062]    A second end  52  of the waste valve assembly  44  opposite the input shaft  84  is interconnected the water valve assembly  46  such that rotation of the waste valve assembly  44  from its closed position to its open position moves the water valve assembly  46  from a closed condition to an open condition. The water valve assembly  46  is shown to generally include a water valve fitting  90  and a water valve body  92 . The water valve body  92  houses a ball valve (not specifically shown) that is movable between an open position and a closed position. Insofar as the present invention is concerned, the water ball valve is otherwise conventional in construction. 
         [0063]    In the embodiment illustrated, the water valve assembly  46  is indirectly connected to the waste valve assembly  44  through a gear arrangement  96 . The gear arrangement  96  is shown to include a first or waste gear  98  meshingly engaged with a second or water gear  100 . The gear reduction provided by the gearing arrangement  96  allows the water valve to rotate through a lesser degree as compared to the waste ball valve assembly  44 . 
         [0064]    In the illustrated embodiment, an initial rotation of the waste ball valve assembly  44  through approximately 15 degrees does not function to open the discharge opening  106  of the bowl assembly  12 . However, the water valve is opened for purposes of delivering flush water to the bowl  24 . Further rotation of the waste ball valve assembly  44  functions to open the discharge opening  20  and continue to deliver flush water to the bowl  24 . In this manner, additional flush water can be delivered to the bowl  24  as desired through partial rotation of the lever  42  from the first position. 
         [0065]    With particular reference to the cross-sectional views of  FIGS. 3 through 5  and  FIG. 13 , the seal member  54  of the present invention will be described. As will become understood by those skilled in the art, the seal member  54  provides a single element that performs the function of sealing a vitreous china bowl  24  to a plastic base  14  and also performs the function of sealing at a waste ball valve assembly  44 . The sealing member  54  also functions to wipe the waste ball valve assembly  44  as the waste ball valve assembly  44  is moved from its closed position to its open position. 
         [0066]    The seal member  54  is retained in the housing  14  by a retaining member  102 . The seal member  54  is toroidal in shape and defines a central opening  104 . The central opening  104  tapers in an upward direction to facilitate mating engagement with the central portion  48  of the waste ball valve assembly  44 . The seal member  54  includes an upwardly extending cylindrical flange  106  and a lower, generally horizontal portion  108 . In one particular embodiment, the upwardly extending cylindrical flange  106  is constructed a compressible foam rubber and the lower, generally horizontal portion  108  is constructed of generally incompressible solid rubber. The upper and lower portions  106  and  108  are laminated to one another. 
         [0067]      FIG. 13A  illustrated an alternative seal member  54 ′ that is injection or compression molded of a common rubber material. The material of the seal member  54 ′ is a relatively incompressible rubber. Many suitable materials are well known in the art. The upper portion  106  of the seal member  54 ′ is shown to include an open cross section to maintain the compressibility of the seal member  54 ′ in a vertical direction. 
         [0068]    The upwardly extending cylindrical flange  106  is compressed between the bowl assembly  12  and the base  14  and provides a water-tight seal between the bowl assembly  12  and the base  14 . Thus, a single seal member  54  performs the dual functions of sealing the vitreous china bowl assembly  12  to a plastic base  14  and sealing/wiping at a ball valve assembly  44 . The horizontal portion  108  engages the waste ball valve assembly  44  and maintains contact with the central portion  48  of the waste ball valve assembly  44  throughout its rotation. In this manner, the seal member  54  provides an improved wiping action to remove waste from the waste ball valve assembly  44 . 
         [0069]    In certain applications it may be desirable to treat the lower surface of the lower portion  108  of the seal member to reduce the effective coefficient of friction. Such a reduction of the coefficient of friction may further facilitate wiping of the central portion  48  of the waste ball valve assembly  44 . In one application, the lower surface of the lower portion  108  is coated with Teflon. In another application, the lower surface of the lower portion  108  is chlorinated. Other materials or treatments may be used within the scope of the present invention to reduce the coefficient of friction. 
         [0070]    The seal retainer  102  provides relative positioning of the seal member  54  to the central portion  48  of the waste ball valve assembly  44 . The seal retainer  102  also provides a surface against which the seal member  54  may be vertically compressed for sealing the vitreous china bowl assembly  12  to the plastic base  14 . In certain applications, the seal member  54  can be over-molded of a thermoplastic material directly to the retainer  102 . 
         [0071]    Incorporation of a single element to seal the bowl assembly  12  relative to the base  14  and to seal the bowl assembly  12  relative to the waste ball valve assembly  44  eliminates errors in assembly that may otherwise result. In this regard, seal arrangements known in the art that incorporate two separate seals are frequently assembled with the wrong seal on top. Additionally, the seals of conventional arrangements are often put in upside down. 
         [0072]    With particular reference to the cross-sectional view of  FIG. 4  also to  FIG. 7 , the flow created for flushing of the bowl  24  by the nozzle  32  will be further described. The nozzle  32  restricts the flow of the flush water and thereby pressurizes the flush water for flushing or rinsing action. In the particular embodiment illustrated, the nozzle  32  includes a single inlet port  120  and functions to divert water in three general directions. As shown in  FIG. 7 , the nozzle  32  defines a laterally extending channel  122 . The opposing sides of the channel  122  angle slightly downward from a lateral center of the nozzle  32 . First and second ends  124  and  126  of the nozzle  32  are open for creating first and second flows of water A and B, respectively. Due to the geometry of the channel  122 , the first and second flows A and B are correspondingly angled slightly downward. An opening  128  in a lower side of the channel  122  provides for a third flow of water C. In one particular application, water dispersed from the nozzle  32  is regulated to a rate of approximately 2.5 gallons per minute. In this application, the flow of water is allocated approximately as follows: A=35%; B=35%; and C=30%. 
         [0073]    As diagrammatically shown in the cross-sectional view of  FIG. 4 , the flows A, B, and C from the nozzle  32  create a flush pattern for full coverage of the bowl  24 . The nozzle  32  pressurizes the water and the rim  26  provides protection against splashing. The water flows A and B define a symmetrical pattern and converge at an imaginary line X that passes through the nozzle and the front of the bowl  24  directly opposite the nozzle  32 . The increasing horizontal width of the ledge  27  and the increasing slope of the ledge  27  as the ledge continues from adjacent the generally vertical surface  29  causes the water flows A and B to gradually cascade downward from opposing directions as they progress toward the front of the bowl  24 . In this manner, water from flow A and flow B is under enough pressure even under lower pressure conditions to provide complete wetting of the bowl  24 . 
         [0074]    With particular reference to  FIGS. 1 and 2 , the shroud will be further described. In the embodiment illustrated, the shroud  16  is integrally molded of a plastic material. In one particular application, the shroud is constructed of TPO or other suitable plastic material. Incorporation of a compliant material allows for variable fit to the bowl assembly  14  to accommodate for vitreous china processing tolerances. 
         [0075]    In one application, the shroud  16  is constructed of a composite material including a microbacterial agent. For example, the composite material may include an antimicrobial biocidic. The composite material would be capable of killing bacteria on contact. 
         [0076]    The shroud  16  is illustrated to include a side wall  130  that wraps around the base  14  of the toilet  10 . As perhaps shown most clearly in the exploded view of  FIG. 2 , the side wall  130  has two ends  132  and  133  that terminate at a vertically extending centerline. The resilient nature of the shroud  16  allows the ends  132  and  133  to be separated sufficiently from one another for attachment to or removal from the base  14 . A lower portion of a front side of the shroud  16  is shown to include a cut-out  132 . The cut-out  34  accommodates the lever  18 . A rear side of the shroud  16  is formed to include a pair of flanges that accommodate the water valve assembly  40 . The plastic material of the shroud  16  reduces the china material required while maintaining an aesthetically pleasing appearance. In this manner, the weight of the toilet  10  is reduced approximately 2.5-4.0 pounds. 
         [0077]    The shroud  16  is integrally formed to include two pairs of flanges  138 . An upper pair of flanges  138  align with one another and receive an elastic member in the form of an O-ring  140  for securing the first and second ends  132  and  133  of the sidewall  130 . A lower pair of the flanges  138  similarly align with one another and receive an O-ring  140  for further securing the first and second ends  132  and  133 . Removal of the O-rings  138  allows the shroud  16  to be easily removed from the remainder of the toilet  10  for cleaning or replacement. 
         [0078]    Turning now to  FIGS. 14  though  20 , a flush toilet constructed in accordance with a second embodiment of the present invention is illustrated and generally identified at reference character  200 . Various elements of the toilet  200  of the second embodiment are common with the toilet  10  of the first embodiment described above. Principally in this regard, the flush arrangement  40  and seal member  54  are common between the two embodiments. For this reason, these features need not be particularly described with respect to the second embodiment. 
         [0079]    The flush toilet  200  is illustrated to generally include a bowl assembly  212  and a base or housing  214 . The bowl assembly  212  is constructed of a vitreous china. The base  214  is constructed of plastic. A shroud or wrap  216  surrounds an outer portion of the bowl assembly  212 . 
         [0080]    The bowl assembly  212  is shown to include at its lower end a discharge outlet or opening  220 . The discharge outlet  220  is defined by a downwardly projecting portion  222 . The upper end of the bowl assembly  212  is open to define a bowl  224 . The bowl assembly  212  is bolted or otherwise suitable securely fastened to the base  214  in any well known manner in the art. 
         [0081]    The bowl assembly  212  of the flush toilet  200  is constructed without a rim (i.e., the bowl assembly  212  has an open-bowl design). Rather, the bowl assembly  212  includes an upper surface  228  and a downwardly extending flange  230 . As will become more apparent below, an upper edge of the shroud  216  is received between the downwardly extending flange  230  and the sidewall of the bowl assembly  212 . 
         [0082]      FIGS. 15 and 17  illustrate the toilet  200  to include a nozzle  32  similar to the nozzle discussed above. As such, the nozzle generally creates the symmetrical water pattern discussed above. Use of the nozzle  32  with the open-bowl design of the bowl assembly  212  may require dynamic flow control of the source of flush water. In this regard, it may be necessary in certain applications to dynamically restrict to flow of flush water to the nozzle  32  to a predetermined maximum pressure to prevent splashing from the bowl  224 . Such dynamic flow control will be understood to be conventional insofar as the present invention is concerned. One suitable type of dynamic flow control is commercially available from Thetford Corporation with its toilets sold under the Aurora® trademark. 
         [0083]    Turning to  FIGS. 19 through 21 , an alternative nozzle  240  for use with the toilet  200  will be described. As will become more apparent below, the nozzle  240  is operative for creating an asymmetrical pattern. In certain applications, the nozzle  240  may be used with the open-bowl design of the bowl assembly  224  without the need for dynamic flow control. 
         [0084]    The nozzle  240  is generally illustrated to include a front component  241  and a rear component  243 . The components  241  and  243  are registered and fastened together. The nozzle  240  restricts the flow of the flush water and thereby pressurizes the flush water for flushing or rinsing action. In the particular embodiment illustrated, the nozzle  240  includes a single inlet port  242  integrally formed with the component  243 . The components  241  and  243  cooperate to direct water in three general directions. As shown in  FIG. 19 , the nozzle  240  defines a generally, laterally extending channel  245 . The opposing sides of the channel  245  angle slightly downward from a lateral center of the nozzle  240 . First and second ends  244  and  246  of the nozzle  240  are open for creating first and second flows of water D and E, respectively. Due to the geometry of the channel  245 , the first and second flows D and E are correspondingly angled slightly downward. A plurality of openings  248  in a lower side of the channel  245  provides for a third flow of water F. In one particular application, the flow of water creates an asymmetrical pattern and is allocated approximately as follows: D=50%; E=20%; and F=30%. 
         [0085]    As diagrammatically shown in the top view of  FIG. 21 , the flows D, E, and F from the nozzle  240  create a flush pattern for full coverage of the bowl  224 . The nozzle  240  pressurizes the flush water and the water flows D and E create the asymmetrical pattern that converges at an imaginary line Y is offset from the imaginary line X that passes through the nozzle  240  and the front of the bowl  24  directly opposite the nozzle  240 . In the particular embodiment illustrated, the imaginary line Y defines a tangent to the bowl  224  that is located approximately 120 degrees clockwise from the nozzle  240 . The geometry of the bowl  224  causes the water flows D and E to gradually cascade downward from opposing directions as they progress toward the imaginary line Y. In this manner, water from flow D and flow E is under enough pressure even under lower pressure conditions to provide complete wetting of the bowl  224 . 
         [0086]    With particular reference to  FIGS. 14 through 17 , the shroud  216  will be further described. In the embodiment illustrated, the shroud  216  is integrally molded of a plastic material. In one particular application, the shroud  216  is constructed of a polypropylene. As with the shroud  16 , the shroud  216  may be constructed of a composite material including a microbacterial agent. The shroud  216  is illustrated to include a side wall  250  that wraps around the base  114  of the toilet  200 . As perhaps shown most clearly in the exploded view of  FIG. 18 , the side wall  250  has two ends  252  and  254  that terminate at a vertically extending centerline. The resilient nature of the shroud  216  allows the ends  252  and  254  to be separated sufficiently from one another for attachment to or removal from the unit  200 . An upper edge of the shroud  216  is received between the downwardly extending flange  230  and the sidewall of the bowl assembly  212 . A rear side of the shroud  216  is formed to include an opening that accommodate the water valve assembly  40 . The plastic material of the shroud  216  reduces the china material required while maintaining an aesthetically pleasing appearance and providing an easier cleaned surface. 
         [0087]    Adjacent the lower end of the shroud  216 , cooperating structure is provided for securing the first and second ends  252  and  254  together. In this regard, a fastener  256  passes through an aperture (not particularly shown) in a boss portion of the first side and engages a projection  258  of the second side  254 . Adjacent an upper edge, the shroud  216  is integrally formed to include a pair of rearwardly extending projections  262 . Both of the sides  252  and  254  are formed to include one of the projections  262 . The projections  262  receive an elastic member in the form of an O-ring  264  for securing the first and second ends  252  and  254  of the sidewall  250 . Removal of fastener  256  and the O-ring  264  allows the shroud  216  to be easily removed from the remainder of the toilet  200  for cleaning or replacement while the bowl assembly  224  is secured to the base  214 . 
         [0088]    The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention. Furthermore, the present invention has been described with reference to two particular embodiments having many common and some distinct features. One skilled in the art will recognize that these features may be used singularly or in any combination based on the requirements and specifications of a given application or design.

Summary:
A flush toilet includes a bowl assembly defining a bowl. The bowl assembly has a discharge outlet at a lower end and a ledge circumferentially extending about a substantial portion of the bowl. The bowl has a rear surface that is generally flat and vertical. The rear surface transitions to the ledge as the bowl continues clockwise and counter clockwise from the rear surface. A horizontal dimension of the ledge increases as the ledge continues from the rear surface to a front of the bowl. An angle of the ledge increases as the ledge continues from the rear surface to the front. A maximum slope of the ledge is located proximate the front. A nozzle is mounted to the bowl assembly for pressurizing a source of flush water and delivering the source of flush water to the bowl for rinsing and flushing of the bowl. The nozzle is positioned at a rear portion of the bowl and produces a first flow of water in a first circumferential direction about the bowl and a second flow of water in a second circumferential direction about the bowl. The second circumferential direction is opposite to the first circumferential direction. The ledge cascades the first and second flows of flush water down the bowl as the first and second flows of water move in the first and second circumferential directions, respectively.