Abstract:
Disclosed are various embodiments for prematurely terminating a flush cycle. A valve stem may be coupled to a cable to move the valve stem in an upward direction to initiate a flush cycle. A buoyant float may be configured to engage the valve stem to prevent the valve stem from moving in a downward direction during the flush cycle, until a water level drops below a predefined level. Finally, a second cable coupled to a valve release assembly may be utilized to release the valve stem from the buoyant float to prematurely terminate the flush cycle.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent Application entitled “TOILET FLUSH VALVE WITH BOWL OVERFLOW PREVENTION” having Ser. No. 61/504,176, filed on Jul. 2, 2011. 
    
    
     BACKGROUND 
     A typical toilet used in domestic applications includes a toilet bowl mounted on a floor surface and in communication with a drain to take away the contents of the toilet bowl, and a water supply tank at a higher elevation that provides the proper amount of water during a flush cycle of the toilet bowl. In order to re-fill the tank after a flush cycle, a float in the toilet tank moves down during a flush cycle and opens a fill valve to supply replacement water in the tank. The float responds to the rising level of the liquid in the tank to close the fill valve. If the drain opening of the toilet is clogged and the toilet is flushed, the fresh replacement water coming from the toilet tank to the bowl has no escape, the water level in the toilet bowl rises, and there is a hazard of overflow of the contents in the toilet bowl. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the present disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
         FIGS. 1A-1D  are cross sections of a toilet tank flush valve assembly and illustrate the progressive steps of opening the flush valve and closing the flush valve in anticipation of an overflow condition of the toilet bowl. 
         FIGS. 2A-2D  are similar cross sections of another toilet tank flush valve assembly illustrating similar progressive steps to avoid an overflow condition of a toilet bowl. 
         FIGS. 3A-3D  are similar cross sections of a third toilet tank flush valve assembly illustrating similar progressive steps of an overflow condition of a toilet bowl. 
         FIGS. 4A-4C  are similar cross sections of a fourth toilet tank flush valve assembly illustrating similar progressive steps of an overflow condition of a toilet bowl. 
         FIGS. 5A-5B  are similar cross sections of a fifth toilet tank flush valve assembly illustrating similar progressive steps of an overflow condition of a toilet bowl. 
         FIGS. 6A-6C  are cross sections of the toilet tank flush valve assemblies of  FIGS. 1A-1D , but showing the stand pipe and connection of the toilet flush valve assembly to the toilet tank. 
         FIG. 7  shows a three-dimensional view of the portion of a toilet tank flush valve assembly. 
     
    
    
     DETAILED DESCRIPTION 
     The various structures described herein are applicable to single flush and/or dual flush systems for toilets. Referring now in more detail to the drawings, in which like numerals indicate like parts throughout the several views,  FIG. 1A  discloses a toilet flush valve assembly  10  that is to be mounted in a toilet tank (not shown) in registration with the inlet opening of a toilet bowl (not shown). 
     Toilet flush valve assembly  10  includes a housing  16  that includes at its bottom an outlet opening  18  that registers with an opening of the toilet bowl, and legs  38  define water ports that allow water to flow from the tank through the lower portion of the external housing  16  and through the outlet opening  18  of the toilet flush valve assembly  10  on down through the inlet opening of a toilet bowl. 
     Flush valve assembly  10  includes valve plate  24  that registers with and closes the outlet opening  18  of the toilet flush valve assembly  10 , and upright valve stem  26  is connected at its lower portion to the valve plate  24 . A sealing gasket  25  is disposed on the valve plate  24  and engages with a seal ring  27  that defines an opening of the flush valve assembly  10 . Valve stem  26  extends upwardly through the tubular passage  28  and a cable connector  30  comprising a tubular structure or other structure extends from the upper end of valve stem  26 . 
     Flush actuator cable  32  extends downwardly from the actuator handle (not shown) that is mounted on the toilet tank in which the toilet flush valve assembly  10  is mounted. The flush actuator cable  32  extends downwardly through the upper portion of the external housing  16  and its lower terminal end passes through slot  34  of the cable connector  30 , with an enlarged lower terminal end  36  that projects below the slots  34 . The flush actuator cable  32  is sized and shaped so that it may slip through the slots  34  when moved in an upward direction until the enlarged terminal end  36  engages the cable connector that forms the slots  34 , and further upward movement of the flush actuator cable  32  causes the enlarged terminal end  36  to lift the cable connector  30  and valve stem  26  which, in turn, lifts the valve plate  24 . This opens flush valve assembly  22  to the position as shown in  FIG. 1B . The flush actuator cable  32  slides through a cable sleeve  37  that is rigidly connected to the housing  16 . Specifically, the cable sleeve  37  may be pressure fitted into recesses  39  formed in the housing  16  as shown. In another embodiment, a structural connector may be molded onto the end of the cable sleeve  37  that mates with an opposing structure embodied in the housing  16 . 
     When the valve plate  24  is lifted as described above, it passes the water ports defined by the legs  38  and allows water to flow from the toilet tank through the outlet opening  18  of the toilet flush valve assembly  10  and ultimately through a gasket  13  that mates with a flush orifice, according to one embodiment, that leads into the toilet bowl as will be described. 
     Tiltable float  40  is supported by pivot pin  47  at the mid-level of the external housing  16 , and the float  40  rests on the surface of the water and tilts in accordance with the vertical movement of the surface of the water. The valve stem  26  includes a lateral projection  42  that passes up through the tiltable float  40  when it is lifted by the flush actuator cable  32 . Float  40  includes a laterally extending hook  44  that faces the path of movement of the valve stem  26 . When the valve stem is raised high enough for its lateral projection  42  to pass the lateral extending hook  44  of the float  40 , the lateral extending hook  44  of the float prevents the valve stem  26  from moving in a downward direction. This holds the valve stem and valve plate  24  elevated so that the valve plate  24  does not descend to close the outlet opening  18 , thereby allowing water to drain from the toilet tank through the water port defined by legs  38  in the external housing  16  and into the toilet bowl. This is best illustrated in  FIG. 1B . 
     Float  40  is supported on a pivot pin  47  so that when the water level descends, the float  40  progressively tilts and its laterally extending hook  44  slips out from beneath the lateral projection  42  of the valve stem  26 , allowing the valve stem and the valve plate  24  to move downwardly into closed relationship with respect to the outlet opening  18  of the external housing  16 , thus terminating the flow of liquid to the toilet bowl. 
     As shown in  FIGS. 1A and 1B , a valve release actuator  46  is pivotally mounted on a support plate  48  by a pivot pin  50  extending through the support plate  48  and through the valve release actuator  46 . In this embodiment, the valve release actuator  46  is J-shaped with a downwardly extending foot  52  that is directed toward engagement with the upper surface of float  40 . The opposite end  50  of the valve release actuator  46  is connected to the terminal end  54  of the downwardly extending emergency stop cable  56 . When the actuator  46  is rotated, the foot  52  abuts float  40 , and the actuator  46  exerts a force on the float  40  in the downward direction. 
     When there is a hazard of an overflow condition in the toilet bowl below, the operator of the toilet can move the handle that is connected to the emergency stop cable  56  to lift the cable and thereby tilt the valve release actuator  46  from the position shown in  FIGS. 1A and 1B  to the position shown in  FIGS. 1C and 1D . This causes the laterally extending hook  44  to engage the upper surface or any other appropriate portion of the float  40 , tilting the float  40  so that the float&#39;s outwardly extending hook  44  withdraws from beneath the lateral projection  42  of the valve stem  26 . This immediately removes the support from the valve stem and valve plate  24  so that, under the influence of gravity and the downward movement of the water through the valve outlet opening  18 , the valve stem and valve plate will move downwardly until the valve plate  24  is seated on the outlet opening  18  of the housing  16 . This maneuver tends to completely and abruptly terminate the flow of water from the toilet tank to the toilet bowl, thereby averting the overflow condition of the toilet bowl. 
       FIGS. 2A, 2B, 2C, and 2D  illustrate a second embodiment. The valve plate and valve stem of this embodiment may be the same as previously described with respect to  FIGS. 1A-1D . However, the valve release actuator is embodied in a projection  60  that is rigidly mounted to the float  62 . When the valve stem  64  moves upwardly in response to the pulling force applied by the flush actuator cable  66 , the lateral projection  68  of the valve stem passes the laterally extending hook  70  so that the valve stem comes to rest on the laterally extending hook, while the water in the toilet tank tends to flow out through the open valve of the toilet flush valve assembly and into the toilet bowl. This condition remains until the float  62  tilts enough to withdraw its laterally extending hook  70  out from beneath the lateral projection  68  of the valve stem, whereupon the valve stem and valve plate will move downwardly under the influence of gravity toward a closed relationship with respect to the outlet opening. 
     Should a toilet bowl be stopped up at the beginning of a flush cycle, the operator may pull the cable  72  upward so that its enlarged lower distal end  74  engages and lifts the projection  60  of the right side of the float  62 , tilting the float so that the laterally extending hook  70  slips out from beneath the lateral projection  68  of the stem  64 . The laterally extending hook  70  may tilt in a downward direction to release the valve stem from the buoyant float to prematurely terminate the flush cycle. This allows the stem and its valve plate to move in a downward direction to close the outlet opening of the toilet flush valve assembly. 
       FIGS. 3A, 3B, 3C, and 3D  disclose another embodiment which includes a cable actuated lever  76  that is pivotal about pivot pin  78  in response to the tension applied by emergency stop cable  82 . When the water level is high in the bowl, the downward movement of the distal end  80  of the cable actuated lever  76  will engage the projection  84  of the cable connector  86 , applying downward force to the valve stem  88 , forcing the lateral projection  90  out from beneath the laterally extending hook  92 , allowing the valve stem  88  and its valve plate to move back into a closed relationship with respect to the bottom outlet opening  18 . 
       FIGS. 4A-4C  illustrate a handle assembly that mounts to, for example, the front wall of a toilet tank of a toilet, which may be used for actuating the toilet flush valve assembly of the previously described products. 
     A flush lever assembly  101  includes a housing  102  that is mounted to the internal surface of the vertical sidewall of a toilet tank. A lever  104  has its stem  106  extending through an opening in the sidewall of the housing  102 , with the lever being positioned externally of the toilet tank and the housing internally of the toilet tank. 
     As shown in  FIG. 4B , stem  106  is connected to cam  108  that rotates as indicated by the double-headed arrow in response to the rotation of the lever  104 . A slider  110  is located within the housing  102  and moves laterally with the housing as guided by rails  112 . Flush actuator cable  114  is connected at its internal end to slider  110  and extends laterally through the housing  102 . 
     When the lever  104  is pivoted downwardly as indicated by arrow  117 , the cam  108  pushes the slider  110  to the left as shown in  FIG. 4B , causing the actuator cable  114  to retract into the housing  102 . This movement of the cable is used to begin a flush cycle in the previously described devices. 
     As shown in  FIG. 4C , the same flush lever assembly  101  includes an emergency stop button  116  that is spring urged so as to protrude from the lever  104 . Alternatively, the emergency stop button  116  may be flush with the surface of the lever  104  or may be recessed with respect to the surface of the lever  104 . The stem  118  extends from the emergency stop button  116  into the housing  102  for engagement with an L-shaped lever  120  that is mounted on pivot pin  122 . Emergency stop cable  124  is connected to the downwardly extending arm  126  of the L-shaped lever  120  so that when the horizontally extending arm  128  of the lever is pivoted downwardly, the downwardly extending arm pulls the emergency stop cable  124 . The emergency stop cable  124  terminates into an enlarged end portion  127  that is retained by the downwardly extending arm  126 . It is understood that the cables  114  and  124  are enclosed in cable sleeves  129 . 
     It will be noted that the flush lever assembly of  FIGS. 4A and 4B  may be used with the previously described toilet flush valve assemblies. 
       FIGS. 5A and 5B  show another flush lever assembly that may be used with the previously described toilet flush valve assemblies. Note that structural components that mate the lever  130  with the housing  134  are not shown. 
     The lever  130  is connected to a stem  132  that extends from outside to the inside of the toilet tank. A housing  134  is mounted to the inside vertical surface of the toilet tank housing. Laterally extending double ended actuator arm  136  is rigidly mounted to the stem  132 . Sliders  138  and  140  are movable along the length of the housing  134 . The ends of the actuator arm  136  engage the sliders so that when the flush lever  130  is rotated, the actuator arm  136  will move the sliders in opposite directions. This causes the flush actuator cable  142  to move along its length in directions opposite to the directions of movement of the emergency stop cable  144 . 
     When the user of the toilet rotates the flush lever in one direction, a flush cycle begins. However, should there be a hazard of toilet bowl overflow, the user can rotate the flush lever in the opposite direction to apply movement of the emergency stop cable and thereby terminate the flush cycle. 
     The foregoing disclosure is focused on the overflow prevention features of the toilet flush valve assembly. The mounting of the toilet flush valve assembly to the toilet tank, the arrangement of the stand pipe, the tank flush valve and float assembly and other items are not specifically disclosed herein but are shown in U.S. patent application Ser. No. 12/715,757. Further, applicant incorporates herein by reference U.S. patent application Ser. No. 12/715,757 in its entirety. 
       FIG. 6A  shows the toilet flush valve assembly  10  that comprises an integrally molded portion of a flush valve  200 . Alternatively, the toilet flush valve assembly  10  may be rigidly connected to the remaining portion of the flush valve  200  via a screw fit connection, a pressure fitted connection, or some other connection that provides for proper sealing to prevent leakage of water. The flush valve  200  includes a standpipe  203  and is mounted to a floor  206  of a toilet tank. In one embodiment, the flush valve  200  includes a thread  209  that engages a nut (not shown) to fasten the flush valve  200  to the floor  206  of the toilet tank. A gasket  213  may be positioned to form a seal between the flush valve  200  and the floor  206  of the toilet tank to prevent leakage. 
       FIGS. 6B and 6C  show the toilet flush valve assembly  10  mounted to a previously existing flush valve  230  via a gasket  233  that is attached to the toilet flush valve assembly  10  at slots  236  near the outlet opening  18 . In  FIG. 6C , the toilet flush valve assembly may slide over or otherwise be connected to a standpipe  203  to align the toilet flush valve assembly  10  with the outlet opening  18 , as is shown in  FIG. 6B . 
       FIG. 7  shows a bottom portion  253  of the toilet flush valve assembly  10  that illustrates the legs  38  and water ports  256  that allow water to flow through the opening  118  and into the toilet bowl. 
     Although preferred embodiments of the invention have been disclosed herein, it will be obvious to those skilled in the art that variations and modifications of the disclosed embodiments can be made without departing from the spirit and scope of the invention.