This Application claims the benefit of U.S. Provisional Application No. 62/024,126, filed Jul. 14, 2014. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to indoor plumbing and gravity-operated flush toilets. More particularly, the present invention relates to flapper valves that are used in such toilets and to an improved flapper valve and assembly of the type that has variably adjustable mounts such that the flapper valve is attachable to a variety of flush valve housings. Further, the two-way adjustment of the rotatable leg clips allows for use of the same flapper valve with a variety of makes and models of flush valves, and flush valves having pegs that may be spaced apart so as to adjust for pegs that may have different diameters or that may be separated from one another by different distances, depending on the flush valve used in the toilet. 
     BACKGROUND OF THE INVENTION 
     Conventional gravity-operated flush toilets have several basic components. The porcelain or china components include a bowl and a water tank mounted on top of a rear portion of the bowl. The bowl and tank can be separate pieces bolted together to form a two-piece toilet. Other gravity-operated flush toilets are made as a one-piece toilet in which the bowl and tank are made as one continuous integral piece of china. 
     More importantly, the plumbing components of a gravity-operated flush toilet include a fill valve in the tank which is connected to a water supply line, a flush valve surrounding a drain hole in the bottom of the tank that communicates with the bowl, and a flapper valve that normally closes and seals the flush valve or, more precisely, the main flush valve orifice. 
     Toilet flapper valves are typically formed as a single structure having a rim for sealing the main flush valve orifice with the flapper valve rim following flushing. The flapper valve is often formed of a soft elastomeric material and is hinged to allow the valve to be pivotally moved upwardly and away from the main flush valve orifice by means of a chain that is connected to the flush handle on the outside of the tank. Once the tank empties, the flapper valve then returns to a position where it seals the main flush valve orifice, the rim of soft elastomeric material forming a sealing area about that main flush valve orifice. 
     The hinged toilet flapper valve mentioned above is typically secured to the flush valve by virtue of a pair of spaced apart parallel mounting arms. The mounting arms also typically include apertures, the apertures being used to rotatably connect the flapper valve to pegs that form part of the flush valve. Depending on the make and model of toilet tank, the size of its flush valve determines how far apart the mounting arms must be in order to accommodate a specific size of flapper valve for that flush valve. That is, the two-way adjustment of the rotatable leg clips of the present invention allows for use of the same flapper valve with a variety of makes and models of flush valves, and flush valves having pegs that may be spaced apart so as to adjust for pegs that may have different diameters or that may be separated from one another by different distances depending on the flush valve used in the toilet. 
     Located forwardly of the flapper valve mounting arms is also a ballast structure which controls the buoyancy of the flapper valve. The buoyancy of a flapper valve is an important function because it determines how much or how little water is used to empty the water tank upon flushing, thus creating water conservancy issues. The buoyancy of the flapper valve is determined by how quickly air is allowed to escape from the ballast. One way that the buoyancy of the flapper valve ballast can be controlled is by controlling the rate at which air within the ballast can flow out of the ballast. This can be done by creating and/or adjusting the size of an aperture at a point within the flapper valve ballast. 
     In the experience of this inventor, flapper valves of current manufacture do not provide an easy-to-use and adjustable flapper valve which combines both functionalities into a single structure. 
     SUMMARY OF THE INVENTION 
     Accordingly, a primary objective of the device of the present invention is to provide a new, useful and non-obvious improved toilet flapper valve that can be used to cover and seal the main flush valve orifice, which flapper valve comprises a pair of rotatable legs and leg clips having two-way adjustment capabilities and which serve to function as the “mounting arms” described above. Significantly, the two-way adjustment of the rotatable leg clips allows for use of the same flapper valve with a variety of makes and models of flush valves, and flush valves having pegs that may be spaced apart so as to adjust for pegs that may have different diameters or that may be separated from one another by different distances depending on the flush valve used in the toilet. The flapper valve of the present invention also includes a variably-adjustable air outlet capability. 
     The foregoing and other features of the improved flapper valve of the present invention will be apparent from the detailed description that follows. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a top, front and left side perspective view of one embodiment of an improved flapper valve that is constructed in accordance with the present invention. 
         FIG. 2  is a bottom, rear and right side perspective view of the flapper valve shown in  FIG. 1 . 
         FIG. 3  is a top plan view of the flapper valve illustrated in  FIG. 1  and showing the mounting legs in a “narrow setting” position. 
         FIG. 4  is a view similar to that illustrated in  FIG. 3  and showing the mounting legs in a “wide setting” position. 
         FIG. 5  is a cross-sectioned left side elevational view of the flapper valve shown in  FIG. 1  taken along line A-A of  FIG. 3 . 
         FIG. 6  is a rear elevational view of the flapper valve shown in  FIG. 1 . 
         FIG. 7  is a front elevational view of the flapper valve shown in  FIG. 1 . 
         FIG. 8  is an enlarged top and partially sectioned view of the leg clip mounting structure in accordance with the present invention. 
         FIG. 9  is an enlarged side and partially sectioned view of the captive portions that are built into the flapper body of the flapper valve of the present invention and showing how an edge of the cone is captured and how an edge of the rotatable vent ring is captured as well. 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to the drawings in detail, wherein like-numbered elements refer to like elements throughout,  FIGS. 1 and 2  generally illustrate a preferred embodiment of an improved flapper valve, generally identified  10 , that is constructed in accordance with the present invention. The improved flapper valve  10  is the type that is intended to be used with a toilet flush valve and main flush valve orifice (not shown). As illustrated, the improved flapper valve  10  is comprised of four primary elements: a flapper body  20 ; a pair of mounting legs  30  disposed rearwardly of the flapper body  20 ; a cone  40  disposed below the flapper body  20 ; and a rotating vent band  50  disposed below the flapper body  20  and about the cone  40 . 
     The flapper body  20  is typically made of an elastomeric material such as real or synthetic rubber having a suitable durometer or softness. In the preferred embodiment, the flapper body  20  is comprised of a real rubber material for suitable sealing with chemical resistance by virtue of CHLORAZONE® additive (CHLORAZONE is a registered trademark of Lavelle Industries, Inc. The flapper body  20  has a top surface  21 , a bottom surface  23  and a circumferential peripheral lip  22 . 
     Forwardly of the top surface  21  of the flapper body  20  and extending upwardly from that top surface  21  is a connection structure  25 . The connection structure  25  typically includes an aperture (not shown) to receive a hook and chain-like structure (also not shown) for lifting the flapper valve  10  upwardly during the initiation of the flush cycle of the toilet. The peripheral lip  22  is configured to mate with the valve seat (also not shown) of the main flush valve orifice to close off water flow through that orifice. 
     Extending rearwardly of the flapper body  20  and also disposed on the top surface  21  thereof is a pair of spaced-apart parallel leg clip mounting structures  24 . Each mounting structure  24  comprises a rearward flat  26  and a frustroconical retainer  28  extending rearwardly from the flat  26 . See  FIGS. 3 and 8 . The retainer  28  comprises a peripheral groove  29  that is disposed immediately adjacent the rearward-facing surface  126  of the rearward flat  26 . Extending forwardly of the rearward flat  26  is a plurality of support ribs  27 . The mounting structures  24  and all of their respective component structures are integrally formed as part of the flapper body  20 . 
     Attachable to each flat  26  of the leg clip mounting structures  24  is a mounting leg  30 . The mounting leg  30  is a substantially L-shaped structure having a forward facing flat  36 , which flat  36  has a hole  39  defined in it. The hole  39  is configured to receive the retainer  28  of the flapper body  20 , the hole  39  capturing the retainer  28  via the peripheral groove  29 . The retainer  28 , like the remainder of the flapper body  20 , is made of rubber which allows the retainer  28  to collapse when pulled on to pass through the hole  39  in the flat  36  of the leg  30 . Once captured, the mounting leg  30  is rotatable about the axis of the retainer  28  such that the mounting legs  30  can be rotated inwardly and set in a “narrow setting” position, as is shown in  FIG. 3 , or rotated outwardly and set in a “wide setting” position, as is shown in  FIG. 4 . 
     Extending rearwardly from the flat  36  is a clip portion  32 , the clip portion  32  being disposed substantially perpendicular to the flat  36 . The clip portion  32  comprises a first clip member  31  and a second clip member  33  which, together, provide a pincer action such that the mounting legs  30  can “capture” the pegs (not shown) of a flush valve (also not shown) of conventional manufacture within an opening  34  formed between the clip members  31 ,  33  to rotatably connect the flapper valve  10  to the flush valve. See  FIG. 5 . This allows the mounting legs  30  to rotate the flapper valve  10  when the flush valve is actuated. It should also be appreciated that the size of the mounting legs  30  can be altered to accommodate flush valve pegs of different diameters. That is, a mounting leg  30  having a wider or narrower opening  34  is intended to be included within the scope of this invention. 
     Extending upwardly from the bottom surface  23  of the flapper body  20  is a round and circumferential captive portion  127 . This captive portion  127  of the flapper body  20  is configured to receive a portion of the cone  40  within a first groove  128  and a portion of the vent band  50  within a second groove  129 . The cone  40  comprises a hollow cup-like structure defining a cone cavity  42 . The cone  40  further comprises a substantially horizontal upper cone edge  44 . The upper cone edge  44  is captured within and held in place by the first groove  128  of the flapper body  20 . The cone  40  further comprises an upper cone wall  43  having an outer surface  41  and a cone bottom  45  having an opening  46  defined in it. The upper cone wall  43  likewise has a plurality of openings  47  defined in it, the openings  47  facing forwardly of the flapper body  20 . These openings  47  work with the vent ring  50  to control air outflow from the cone cavity  42 . Further, the cone  40  comprises a polarizing tab (not shown) to ensure proper positioning of the cone  40  relative to the flapper body  20 . In other words, the cone  40  is attached and polarized in one position so that the holes or openings  47  in the cone  40  can only be positioned one way, which is forward. In short, the cone  40  is integral with the flapper body  20  and does not rotate. Lastly, the cone  40  comprises a plurality of snap tabs  48  extending outwardly from the outer surface  41  of the upper cone wall  43 . The snap tabs  48  are used to maintain the vent band  50  in a position such that the band  50  is rotatable about the upper cup wall  43  but is not able to move vertically relative to that wall  43 . The upper cup wall  43  further comprises indicia  140  to indicate to the user that the rotatable band  50  is functionally disposed about the cone  40  in several positions. See  FIG. 6 . 
     The rotating vent band  50  comprises a flat ring-like structure comprising a cylindrical band body  52  having an inner surface  51 , an outer surface  53 , an upper band body lip  58  and a plurality of support ribs  54 . As shown in  FIG. 9 , the upper band body lip  58  is receivable within the second groove  129  of the captive portion  127  of the flapper body  20 , the band body  52  further being rotationally-movable about the outer surface  41  of the upper cone wall  43  of the cone  40 . The vent band body  52  further comprises a substantially plurality of circular apertures  56 . The vent band body  52  is rotatable to place the apertures  56  in several different positions to achieve desired air flow out of the cone cavity  42 . In short, the vent band  50  is a locking device that captures the flapper body  20  and the cone  40 . That is, it is a metering device that rides on the edge of the cone  40  which prevents binding during rotation. The vent band  50  further provides detents (not shown) which allow the band  50  to be positioned in specific settings. 
     The present invention also contemplates use of the flapper valve  10  in combination with a flush valve as described at the beginning of this disclosure. This use would be an assembly of the type that could be installed within the tank of a conventional toilet.
An improved toilet flapper valve is used to cover and seal a main flush valve orifice, which flapper valve comprises a pair of rotatable legs and leg clips having two-way adjustment capabilities and which serve to function as mounting arms. The two-way adjustment of the rotatable leg clips allows for use of the same flapper valve with a variety of makes and models of flush valves, and flush valves having pegs that may be spaced apart so as to adjust for pegs that may have different diameters or that may be separated from one another by different distances depending on the flush valve used in the toilet. The flapper valve of the present invention also includes a variably-adjustable air outlet capability.