Abstract:
A hollow, open-ended closure for the tank valve which enables a large cross-section area of discharge port to be used, and which can pass bowl-refill water during the flushing sequence. It is especially useful as part of a valve in which it can be tilted to open the tank valve with reduced physical effort.

Description:
CROSS REFERENCE TO OTHER PATENT APPLICATION 
   This is a division of applicant&#39;s U.S. patent application Ser. No. 10/291,220, filed Nov. 7, 2002 now U.S. Pat. No. 6,910,232. 

   FIELD OF THE INVENTION  
   A closure for a fast-discharge, small volume toilet tank flush system. 
   BACKGROUND OF THE INVENTION  
   The advent of indoor plumbing and flush toilets, and decades of use and gradual improvement started with simple plug and flapper tank valves that were levered open, to remain open while a full tank emptied, and a ballcock valve which was open whenever the water level in the tank was below a storage level. While the ballcock valve was open, part of its total flow was diverted to refill the bowl at the same time the tank was being refilled. That procedure remains the same to this day for systems which use stored water to flush the toilet. 
   Nearly every year there has been an improvement in some part of the conventional systems. Tank-valves have evolved into many forms of pivoted plates and floats. Ballcock valves have evolved from simple floats on a lever that pressed on a valve plate, to differential pressure actuated valves that require movement by the float of only a pin to open or close a very small bleed orifice for their control. 
   The floats themselves have evolved from copper spheres to foam bodies, to inverted cups of various shapes. Some were on lever arms. Others embraced an upright post. The ultimate limit on the water level was overflow into the bowl, through the same passage as was provided for the bowl refill. 
   The industry was greatly assisted by the development of plastic materials of construction. These materials need to resist pressure-for a long time and also resist chemicals which would show up in the water from time to time. They enable the production of shapes and parts which could not economically be produced by metal casting and machinery processes. 
   As a disadvantage these new shapes and materials also enabled the production of sophisticated products in low-cost countries, to the disadvantage of domestic production. As a consequence, there has been significant incentive to invent and market even more sophisticated products hopefully made as inexpensively and perhaps better in the United States. 
   If it were merely a matter of making a same thing cheaper, there would be no merit in making changes. However, as the availability of these products (in part because of their low cost) improved, and along with population growth, the effluent from their systems also has increased to the extent that sewage systems designed for lesser loads are being overwhelmed. 
   The response to this problem has been to redefine how much water a toilet is permitted to discharge per flush. Low volume flush systems are now routinely required. Whereas in the past a large flush which depended on a sustained and relatively slow flow of water was the norm, now a much lesser amount of water is permitted for each flush cycle to do the same job. In order for this to happen a quick, high rate of flow of a low total volume of water is needed to wash away the waste. 
   Systems using direct flow from a pressure valve can often attend to this, but systems favored in less commercial places such as residences tend to use water tanks. It is an object of this invention to provide a water tank system with the capability of a sufficient and very rapid discharge of stored water. 
   As it happens, such improved systems involve related problems of their own. While each problem is relatively small, together they add up to a significant challenge. For example, to discharge a large volume quickly requires a large area discharge port and an equally large closure for it. The force required to lift the closure off of the discharge port valve seat is proportionally increased to the extent that it is difficult for an average person to operate. 
   Here, the ultimate problem is in the inefficiency of the trip lever used to lift the valve. The lever is inherently inefficient because the outside handle or knob available to the user is short, and the inside lever it turns is long. In itself it magnifies the force necessary to turn the handle, thereby compounding the problem. 
   It is an object of this invention to reduce the force needed to open the tank valve. In fact, without the improvements of this invention it may take as much as 10 pounds force on a 3 inch handle to open the valve. With the improvements of this invention, the required force to open a 3 inch diameter plug valve is only about 3 pounds. 10 pounds is too much force for many people, while 3 pounds is tolerable by almost everybody. 
   Another problem arises from the-variations of dimensions of installed systems. To compensate for these, trip levers have often lifted a valve closure with flexible links such as chains or cables. This invention provides a lifting lever with a profile suitable for a wide range of dimensions for actuating the valve closure, and which does not require a flexible link. This is a savings in cost and, as will be seen, is also an improvement in function. 
   Conventional tank valves often rely on a pivoted valve closure which is costly and subject to later malfunction. It is an object of this invention to provide a single piece valve closure of surprisingly simple design—a unibody with a distinctive exterior, a passage entirely through the closure, with a lower guide and an upper end receptive of refill water, and which when open is a freely floating body without restraint to the tank structure. It can readily be opened by a tilting, rather than an axial movement, requiring less physical force to open the valve. 
   BRIEF DESCRIPTION OF THE INVENTION  
   This invention is adapted for use in a tank having a bottom and a peripheral sidewall to receive, store and discharge water to flush a toilet. A discharge port is formed through the bottom. A tank valve having a tank valve seal is fitted in the discharge port. This seal is horizontally disposed. 
   A tank valve closure is a hollow circularly-shaped body having an upper opening and a lower opening. It includes a reduced dimension lower guide loosely to guide the closure in the discharge port. A flared-out portion above the guide has a lower valving surface disposed and arranged to rest upon the valve seat to close it. A reduced-diameter neck rises from the flared-out portion, and carries an engagement means to be engaged by a lifting lever, eccentrically from the central axis of the closure. 
   A ballcock valve receives water which on demand supplies the tank with stored water and supplies the bowl with refill water. The ballcock valve is responsive to the water level in the tank. It is closed when the tank is filled to a desired storage level and open when the tank is to be refilled. Its bowl refill tube discharges into the neck of the tank valve closure. 
   Low profile installations frequently require that all of the mechanisms be in the tank, located above its bottom. For such installations, an optional riser may be fitted into the tank&#39;s discharge port and the valve seat is placed well above the bottom of the tank. This enables all parts of the system to be placed in the tank above the bottom, or within a spud just beneath the bottom. 
   The system is actuated by turning a handle which is journaled to the sidewall. When turned it rotates a lever linked to the closure. According to a preferred but optional feature of this invention, the lever is connected to the closure laterally off of its axis so that when it lifts the closure it first tilts it with little effort, which promptly reduces the differential pressure across the closure and thereby reduces the ultimate force needed to open the valve by further lifting the closure. 
   According to a preferred but optional feature of the invention the upper edge of the lifting lever is serrated along part of its length so that it can engage the closure reliably over a wide range of dimensions, and with the closure in a wide range of angular portions around its axis. This enables considerable freedom of movement and adaptability to dimensions of different installations. 
   As another preferred but optional feature of the invention, the handle is attached to the lift lever by a joinder which allows for universal adjustment of the angle between the two. 
   The above and other features of this invention will be fully understood from the following detailed description and the accompanying drawings, in which: 

   
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a side elevation of a toilet tank installation, partly in cutaway cross-section, showing the invention; 
       FIGS. 2 and 2A  are cross-sections taken at line  2 — 2  in  FIG. 1 , showing the tank valve closed and first being opened, respectively; 
       FIG. 3  is an exploded schematic view showing the lift lever and tank valve; 
       FIG. 4  is an enlarged fragment of the lift lever; 
       FIG. 5  is an axial cross-section of the tank valve; and 
       FIG. 6  is a side elevation-similar to  FIG. 1 , showing the system open to flow. 
   

   DETAILED DESCRIPTION OF THE INVENTION  
   A toilet tank  10  has a bottom  11 , a peripheral sidewall  12  and an open top  12   a , which in use is covered by a removable lid (not shown). A central water discharge aperture  13  and an inlet aperture  14  are formed in the bottom of the tank. 
   A ballcock valve  20  is fitted in the inlet aperture by means of a typical spud  21  and nut  22 . Any type of ballcock valve is suitable that provides the necessary functions of opening to flow when the water level  23  in the tank is below a predetermined elevation. At that time the valve workings  25  will supply water to the tank via a discharge tube  26 , and to the toilet bowl through a bowl refill tube  27 . 
   The illustrated valve is fully described in Antunez U.S. Pat. No. 6,244,292 which is incorporated herein in its entirety and made a part hereof by reference for its showing of the construction and operation of the valve workings. 
   A float  28  is wrapped partially around riser  29 . Water under pressure is conveyed through the riser to the valve workings. The float follows the water level to actuate the workings via a linkage  30 . 
   A tank valve  31  is fitted in water discharge aperture  13 . A circular riser  32  is fitted to the tank bottom and held to it by a nut  33 . The riser has a height H for a reason to be described below. 
   A tank valve seat  35  is formed atop riser  32 . If the height of the riser were not necessary, the seat could be formed closer to the bottom. 
   A flexible washer  36  can be provided loosely, or can instead be attached to a closure  40  or to the valve seat so as in effect to form a valve seat, as preferred. A centering guide  41  comprises a group of axially and inwardly extending blades  42 . Their innermost edges form a centering path. Guide  41  is fixed in the riser below the seat. 
   Closure  40  is a hollow structure with a substantially constant wall thickness throughout. It has a dimension of axial length with an upper neck  43 , a bottom guide  44 , and an enlargement  45  between them. Although it is not immediately apparent, this closure will float when its upper end and lower end are vented at the same time and the closure is not seated on the seal. 
   As best seen in  FIG. 5 , the neck, guide, and enlargement forming a continuous passage open from the upper end of the closure to its lower end. 
   The enlargement has a lower surface  46  which can abut and close on the seal (or washer). When it is seated, the lower end will be exposed to atmosphere in the outlet port (which leads to the toilet bowl), and the upper end will be above the water line and thereby also exposed to atmosphere. At this time there is a substantial net downward force on the closure which will keep it closed. 
   Here it will be observed that the bowl refill line discharges into the upper end of the closure, and water from it will flow directly through the closure to the bowl to refill it. 
   The closure is conveniently made by a blow-molding process. Ears  50 ,  51  are formed on the outside of the neck wall, to one side of the central axis  52  of the closure. Alternatively, the ears may be formed on a separate collar to be fitted around the neck. Actuation of the system begins with a full tank and the closure against the tank valve seal to close the tank valve. 
   A lift lever  60  has a free end  61 , and a pivot end  62 . The pivot end is attached to flush handle  63  through the peripheral wall, to both of which they are mounted. In order that the lever and handle can be adjusted relative to one another, the lever makes a press fit in a socket (not shown) in the lever. If desired, axial striations and grooves in the handle can be provide for a greater range of angular relationship between them. Alternatively the lever and socket may have smooth enlarging surface to permit universal adjustments between them. 
   A plurality of holes  64  are provided near the free end of the lever. A circlet  65  can be fitted into one of them after the free end has been inserted through one of the ears of the closure. The circlet will prevent the lever from separating from the closure. The plurality of holes  64  provides for different distances between the location of the ears and the pivot of the handle. 
   A plurality of serrations  66  are formed along the top of the lever where contact is to be made with the ears. In the course of use, the closure may turn around its axis for a few degrees, and also the distance from the ears to the handle may differ among installations. There will always be a serration in which the upper reach of an ear will lodge. 
   The advantage of the off-center lift on the closure will be appreciated from an examination of  FIGS. 2 and 2A . In  FIG. 2 , the closure is firmly seated on the seat, and is held by the pressure derived from the differential pressure on the top surface  70  of the closure which is exposed to water pressure, and the lower surface  46  which is exposed to atmosphere. This is a net heavy load to be lifted by an inefficient lever. 
     FIG. 2A  shows the closure being lifted by the ear. Its first effect is to tilt, rather than axially to lift, the closure. This requires a markedly lesser force than a straight lift. “Cracking” the abutment as shown in  FIG. 2A  immediately releases the downward net force, and the closure can easily be raised the rest of the way. 
   After this is done, the float remains buoyant so long as water is flowing through the outlet port so as to expose the lower surface to atmospheric pressure. When flow stops, the closure will drop and close the outlet, and the net closure force is again exerted. The ballcock valve while still open will provide water directly to the tank and, through the closure to the bowl. 
   Attention is called to the stabilizing effect of the bottom guide  44  and the group of spaced apart blades  42 . While permitting some tilting and sideward movement of the closure, they still keep the closure in line for operation. 
   In the embodiment shown in the drawings, there will always be water in the tank up to the level of the top of riser  32 . This enables the mechanism to be contained entirely inside the tank and that portion of the riser which must extend below the bottom of the tank in any arrangement. 
   It will be noted that many of the advantages of this invention can be obtained by connecting the lever to the ears with a chain. This is another “operative engagement” of the lever and the closure. Therefore the use of a direct connection of the lever and the ears is not a limitation on the invention, but instead is a considerable advantage 
   This invention is not to be limited by the embodiment shown in the drawings and described in the description, which is given by way of example and not of limitation, but only in accordance with the scope of the appended claims.