Abstract:
A flush valve having a cross section of a portion of the drain entrance that while in a rest position is positioned above the water line so that there can be no leakage. When flushed, the entire entrance momentarily falls below the waterline creating a siphon, siphoning water out of the tank flushing the toilet and then once again rises to a position above the waterline so that leakage cannot occur.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application is a continuation-in-part of prior application Ser. No. 10/259,674, filed Sep. 30, 2002, which claims the benefit of U.S. Provisional Application No. 60/327,946, filed Oct. 10, 2001, and U.S. Provisional Application No. 60/348,246, filed Jan. 15, 2002. 
     
    
     
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
         [0002]    Not Applicable  
         REFERENCE TO A MICROFICHE APPENDIX  
         [0003]    Not Applicable  
         BACKGROUND OF THE INVENTION  
         [0004]    A typical toilet tank like that found in most homes has a flush valve located within the toilet tank. A flapper resting on top of the flush valve stops the flow of water through the flush valve and forms a somewhat watertight seal. When the toilet flush handle is pushed downwards, the flapper is lifted allowing water to flow through the flush valve, flushing the toilet. The method of sealing the flush valve with a flapper is common. At some point, the underside of the flapper and the top portion of the flush valve that are in contact and forms a somewhat watertight seal degenerates and begins to leak. Leaking begets leaking and after some time a considerable amount of water is being wasted and the flush valve and flapper must be replaced.  
         BRIEF SUMMARY OF THE INVENTION  
         [0005]    The object of the present invention is to provide a leak proof flush valve that will retrofit existing toilet tanks as well as be able to be installed in new toilet tanks and having a life expectancy of many years and a cost that is less than conventional flush valves. The Leak Proof Toilet Tank Siphon Flush Valve comprises a toilet tank flush valve having a cross section of a portion of its entrance normally resting in a position above the waterline so water can never leak entirely through the entrance. Only when the toilet is being flushed does the entire entrance momentarily fall below the waterline creating a siphon allowing the water to be siphoned out of the tank, flushing the toilet. When most of the water has been siphoned out of the tank, the siphon is broken and a float raises as the fill valve refills the tank again keeping a cross section of the entrance above the water line. 
       
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING  
       [0006]    [0006]FIG. 1 is perspective view of the toilet tank outlet fixture.  
         [0007]    [0007]FIG. 2 is perspective view of the flexible tubing.  
         [0008]    [0008]FIG. 3 is a perspective view of a flush valve seal.  
         [0009]    [0009]FIG. 4 is a perspective view of a partial assembly.  
         [0010]    [0010]FIG. 5 is a plan view of the float.  
         [0011]    [0011]FIG. 6 is a perspective view of the entire assembly in a rest position.  
         [0012]    [0012]FIG. 7 is a perspective view of the entire assembly during a flush cycle.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0013]    The following discloses a means of flushing a toilet by creating a siphon within flexible tubing so that when the toilet is not being used while the toilet tank is full of water, at least one entire cross section of the flexible tubing is entirely above the water surface so that the toilet tank will never leak water while not being used.  
         [0014]    [0014]FIG. 1 shows a tank outlet fixture  1  having a lip  3  and a threaded end  5 . FIG. 2 shows a partial view of flexible tubing  7 . The flexible tubing  7  may have an internal support structure or may be made with ribs or baffles to help maintain the shape of its cross section. FIG. 3 shows a typical flush valve seal  11  having tapered side wills as shown. FIG. 4 shows the assembly of the tank outlet fixture  1 , the flexible tubing  7 , and the seal  11  to a toilet tank  13  of which only a partial representation of the tank  13  is shown. The flexible tubing  7  is fitted over the tank outlet fixture  1  with the threaded end  5  of the tank outlet fixture  1  protruding through the flexible tubing outlet end  9  as shown. The seal  11  is fitted over the flexible tubing  7  and outlet fixture  1  so that the tapered end of the seal  11  is positioned above the tank outlet hole  10  as shown and the top of seal  11  is positioned below the lip  3  of the outlet fixture  1 . The threaded end  5  of the outlet fixture  1  extends through the tank outlet hole  10 . The flexible tubing outlet end  9  also extends through the tank outlet hole  10  as shown. When the fastening element  15  is fastened onto the threaded end  5  of the outlet fixture  1 , the seal  11  forms a watertight seal between the flexible tubing  7  and the tank  13 . FIG. 5 shows a plan view of a float  41  having two holes  43  that extend through the float  41  that are positioned as shown. The float may be made from styrofoam but is not limited to styrofoam. Any suitable buoyant material may be used.  
         [0015]    Referring now to FIGS. 6 and 7. One end of the flexible tubing  7  is fastened and sealed to the tank  13  as previously described and the flexible tubing  7  is fitted into the tank  13  in an upside down U-shaped configuration as shown. This U-shaped configuration is maintained by having the flexible tubing  7  inserted into both holes  43  located in float  41  as shown. In FIG. 6 at least one entire cross section of the flexible tubing  7  that lies in a plane which is at right angles to the walls of the flexible tubing  7  and also at right angles to the surface of the water is entirely above the water surface  37  as shown. One end of the toilet fill tube  29  extends from the toilet fill valve outlet  27  with its other end fed into the flexible tubing inlet end  35  as shown. The float  41  is applying an upwards pressure on the fill valve lever  19  keeping it in an off position so that water is neither entering the tank  13  or the toilet via fill tube  29 . When flush handle  23  is pushed upwards the flexible tubing  7  is forced downwards, via extension  25  pushing downwards on float  41 , so the flexible tubing  7  is substantially submersed beneath the water surface  37  so the inside of the flexible tubing  7  is substantially under and filled with water. The water begins to siphon and drain out of tank  13  through the outlet fixture  1 , shown in FIG. 1 and FIG. 4, lowering the water level  37 . As the water level  37  in tank  13  drops below the upper most portion of flexible tubing  7 , the inside of flexible tubing  7  remains substantially filled with water because of the siphon created when the flexible tubing  7  is substantially submersed beneath the water surface  37  so the water continues to drain out of the tank  13  as previously described until the water surface  37  falls beneath the flexible tubing inlet end  35  breaking the siphon and stopping the draining of water from tank  13 .  
         [0016]    As the water level  37  falls, the fill valve lever  19  falls which opens up fill valve  17  allowing water to enter the toilet via toilet fill tube  29  and allows water to begin filling the tank  13  via tank fill outlets  31 . The tank  13  water level rises pushing upwards on float  41  until the fill valve lever  19  is forced upwards by float  41  far enough and fill valve lever  19  closes, stopping the flow of water into the toilet and tank  13  so that the water level  37  is once again at the position shown in FIG. 6. This completes one flush cycle.  
         [0017]    A float  41  positioned beneath the bottom of the bend in the flexible tubing  7  shown in FIGS. 6 and 7 is used to keep at least one entire cross section of the flexible tubing  7  as previously described entirely above the water surface  37  while the toilet is not being flushed.  
         [0018]    It is an important part of this invention that the distance the bottom of the flexible tubing end  35  is from the bottom of the tank  13  at the time the siphon is broken and water stops draining from tank  13 , substantially defines the amount of water used during one flush cycle. It is also an important note that fill tube  29 , used to fill the toilet bowl, is not necessarily needed with this type of flush valve. After the siphon begins to break and the toilet completes its flush, there is enough water still being siphoned after completion of the flush and before the siphon to completely broken to fill the toilet with enough water for the next flush. Prior to this invention, water entering the toilet via toilet fill tube  29  was the source used for this purpose. In other words, the toilet fill tube  29  and the internal components of the fill valve  17  supporting this portion of the toilet fill valve outlet  27  can be removed from the fill valve  17 , significantly reducing the costs of the fill valve  17 .