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[0001]     The present application is a continuation of U.S. Provisional Patent Application Ser. No. 60/535,738 filed Jan. 8, 2004. This referenced patent application is to be incorporated into the present application in its entirety by this specific reference thereto. 
     
    
       [0002]     The present invention is generally related to pressurized flushed systems for toilets and is more specifically directed to a flushing system that maximizes the efficiency of effluent transport within a pressure baffle and discharge to a toilet bowl.  
         [0003]     Water conservation is an environmental consideration and has resulted in strict controls being placed on domestic water usages.  
         [0004]     Pressurized flushed systems have been developed to conserve water use.  
         [0005]     Often prior art systems do not efficiently discharge water and often require a user to hold open a valve in order that water is fully discharged. Accordingly, a user is required to cooperate with time delay operation in order to efficiently discharge the water from the pressure tank.  
         [0006]     In addition, any prior art devices have no air-in provision. This does not provide efficient water filling into the pressure.  
         [0007]     The present invention overcomes the drawbacks of the prior art.  
       SUMMARY OF THE INVENTION  
       [0008]     The present invention provides an improved structure in which flush performance is not influenced by a users&#39; habits, while providing for simple structure to accomplish this aim.  
         [0009]     A pressurized flush system in accordance with the present invention generally includes a pressure water vessel, having an inlet and an outlet, an infill valve, an open valve, and a flush valve disposed within said pressure water vessel and in fluid communication with said infill valve and said open valve. More particularly, the flush valve includes a hollow valve body and cooperating pistons for controlling water discharge from the water vessel outlet. The cooperating pistons are disposed within the hollow valve body.  
         [0010]     Further, the system flush valve includes a partition disposed within the valve body, with the partition having a hole therethrough and the cooperating pistons include a big piston disposed below the partition and a small piston disposed above the partition within an upper cylinder sleeve, the small piston having a bottom engaging the partition hole.  
         [0011]     Accordingly, the big piston, small piston, upper cylinder sleeve, and partition divide the valve body into a lower cavity, an upper cavity and a normal pressure cavity.  
         [0012]     A normal pressure opening may be disposed in the normal pressure cavity and the small piston may include an opening in the bottom thereof communicating with said upper cavity.  
         [0013]     More particularly, the open valve includes an open valve body with an inlet connected with an outlet of the flush valve, the open valve body includes a water release hole connected to the normal pressure cavity, and the open valve includes a spring loaded handle having a side covering and sealing the open valve body inlet.  
         [0014]     The system further includes a combination valve disposed between the infill valve and the water vessel inlet, with the combination valve including a pressure-controlled valve disposed in a manner shutting of the vessel inlet when the water vessel is discharging water and an air-in device disposed in a manner filling air into the water vessel when water is filled into the water vessel.  
         [0015]     Still more particularly in accordance with the present invention the pressure-controlled valve includes an infill cavity, a water pressure cavity, an infill piston and a pressure-controlled spring, the infill cavity being connected respectively with the inlet duct and the outlet duct of the combination valve; the water pressure cavity being connected with the outlet of the combination valve.  
         [0016]     In addition, the system may include a through hole partition disposed between the infill cavity and the water pressure cavity and the infill piston may be disposed inside the water pressure cavity on which is set a piston rod, which goes through the partition through hole and reaches into an outlet duct with the push of the pressure-controlled spring with and end forming a seal with the outlet duct.  
         [0017]     Further, a spout may be disposed inside the outlet duct of the combination valve with the spout having a necked bottom and an air-in ball valve is disposed in a ring shaped cavity between the outlet duct and the spout, the ball valve forming an air-in device with the spout.  
         [0018]     More specifically, the system includes a water release tube disposed inside the flush valve and located in a middle of the upper cylinder sleeve and extending to the water vessel outlet, a check valve being disposed inside the water release tube.  
         [0019]     Still more particularly, the system includes an outer flank surrounding the vessel outlet and defining an annulus outlet therebetween, the flank including a normal pressure water release hole and a ring shaped check valve is disposed in said annulus outlet below the normal pressure water release hole.  
         [0020]     The system may also include an anti-siphon ball valve disposed in a combination valve inlet duct, the anti-siphon ball valve opening when the pressure in a water supply line is equal or lower than atmospheric pressure.  
         [0021]     Finally, the system may also include a check ball valve disposed in a channel between the connecting valve inlet duct and a combination valve outlet duct, the check ball valve shutting off when pressure in the combination valve outlet duct is higher than pressure in the combination valve inlet duct.  
         [0022]     The flush system in accordance with the present invention has the following advantages:  
         [0023]     1. The structure of the flush valve facilitates effective operation.  
         [0024]     As the present invention has one big and one small piston in the flush valve, and the flush valve body is divided into three cavities; the upper cavity, the lower cavity, and the normal pressure cavity, when to flush the toilet, it is only needed to discharge a small portion of water in the upper cavity to open the big piston, and water in the lower cavity can be temporarily stored in the normal pressure cavity. As pressurized water that need be discharged from the flush valve is much less than that of the prior art, the open valve is not required to be complicated. Generally speaking, only a simple restoring device is needed for the open valve, with which the pressurized water in the upper cavity can be fully discharged with a short press, and the pressurized water in the lower cavity can be temporarily stored in the normal pressure cavity until the flush is completed. And thus the structure of the open valve is much simplified, and the water flush volume as well as the flush performance will not be influenced by different press habits of users.  
         [0025]     2. An air-in device is added at the pressure-controlled switch, performing a combination valve, which improves the flush performance. The present invention utilizes the high-speeded water flow during the initial period, making it carry air when filling and add air into the pressure water vessel, and thus a better flush performance can be attained.  
         [0026]     3. The combination valve mentioned in the present invention is a valve with multiple functions, including a pressure-controlled valve, an air-in device, an anti-siphon device, and a check valve.  
         [0027]     Among these, the pressure-controlled valve can attain a purpose of not to infill when flushing, and can make the flush volume more steady, preventing leakage when the flush valve cannot close due to the low pressure in the water supply system; the air-in device can fill some air into the pressure water vessel when water is filling; the anti-siphon device and the check valve device can prevent backflow from the pressure water vessel into the water supply system and making it polluted.  
         [0028]     4. In the flush valve of the present invention is set a water release tube, which, during the refill stage, can release water stored in the normal pressure cavity when flushing the toilet bowl. There is also a check valve in the water release tube, which can prevent backflow of wastewater from the toilet bowl into the normal pressure cavity caused by the resistance from the toilet bowl when flushing. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0029]     The advantages and features of the present invention will be better understood by the following description when considered in conjunction with the accompanying drawings in which:  
         [0030]      FIG. 1  is a sectional view of the present invention (not in function);  
         [0031]      FIG. 2  is a sectional view of the present invention under efficient flushing stage;  
         [0032]      FIG. 3  is a sectional view of the present invention under a posterior stage of flushing;  
         [0033]      FIG. 4  is a sectional view of the present invention in a refilling stage;  
         [0034]      FIG. 5  is a sectional view of the present invention in a refilling stage; and  
         [0035]      FIG. 6  is a diagrammatical sketch of a prior art pressurized flush system. 
     
    
     DETAILED DESCRIPTION  
       [0036]     With reference to  FIG. 6 , there is shown a prior art pressurized flush system used in toilets that has been widely accepted due to its saving more water than a conventional normal pressure flush system.  
         [0037]     As shown in  FIG. 6 , this pressurized flush system comprises a pressure water vessel  1 ′ fixed in a ceramic tank  6 ′, an infill valve  2 ′, a flush valve  4 ′, and an open valve  5 ′ which can discharge the pressurized water from the flush valve  4 ′. The flush valve  4 ′ is fixed through the pressure water vessel  1 ′ and seals it. Above the outlet  14 ′ in the pressure water vessel  1 ′ is set a refill bar  15 ′, in the bottom of which is set at least one refill orifice  151 .  
         [0038]     The flush valve  4 ′ mainly includes a hollow valve body  41 ′ fixed in the pressure water vessel  1 ′, and a flush piston  42 ′ which is set in the valve body  41 ′ and can hermetically slide in it. The bottom of the flush piston  42 ′ can seal the outlet  14 ′ of the pressure water vessel  1 ′, and on the valve body  41 ′ are set an inlet  411 ′ and an outlet  412 ′. Besides, between the infill valve  2 ′ and the inlet  18 ′ of the pressure water vessel  1 ′ is set a pressure-controlled switch  3 ′ which closes the inlet  18 ′ when water is being discharged from the pressure water vessel  1 ′. The inlet  411 ′ of flush valve  4 ′ is connected with the pressure-controlled switch  3 ′, and the outlet  412 ′ is connected with the open valve  5 ′.  
         [0039]     However, the prior art described has disadvantages as follows:  
         [0040]     1. The structure of the flush valve  4 ′ is too simple, and especially, the flush valve cavity  44 ′ above the flush piston  42 ′ is too big, and thus the water that need be discharge is too much, and all the water will go through the open valve  5 ′, which requires the user delay some time when opening the open valve  5 ′, otherwise, water in the flush valve cavity  44 ′ cannot be fully discharged, making the flush piston close too early, which influences the flush performance for the toilet. Whereas if is not realistic to request the user to cooperate on the time delay, and then the open valve  5 ′ need to have the time delay function, which will make the open valve  5 ′ too complicated.  
         [0041]     2. There is no air-in device. Although in the above patent application the pressure water vessel  1 ′ is under normal pressure during the terminal phase of flushing and the refill process, air form the outside can fill into the pressure water vessel  1 ′ during this period, and a wanted flush performance can be reached even though there is no air-in device, however, during the initial phase of water filling into the pressure water vessel, the energy of high-speeded water flow is not utilized but wasted. If to add an air-in device here, more energy can be stored in the pressure water vessel  1 ′, and the flush performance can be better.  
         [0042]     As shown in  FIG. 1 , the present invention includes a pressure water vessel  1 , an infill valve  2 , a combination valve  3 , a flush valve  4 , and an open valve  5 . The infill valve  2  is fixed at the bottom of the pressure water vessel  1 ; the combination valve  3  is fixed on the top of the pressure water vessel  1 ; the flush valve  4  is fixed through the pressure water vessel  1 ; and the open valve  5  can be fixed at any position of the ceramic toilet tank  6 , namely, the front, side or top of the toilet tank. Below is the detailed description of all these sub assemblies.  
         [0000]     The Pressure Water Vessel  
         [0043]     The pressure water vessel  1  is a sealed container made of high-strength and high-stability material. An opening  11  is centered on the top of the pressure water vessel  1 . The outlet  12  is set under the opening  11  and some external threads are set in the peripheral lower section of the outlet  12  to connect with the inlet of the toilet tank. A locating plate  13  is set at the top of the outlet  12 . An outlet  14  is set under the locating plate  13  and inside the upper section of the outlet  12 , and its inner diameter is smaller than the diameter of the outlet  12 . The cylindrical refill bar  15  is set at the peripheral of the locating plate  13 .  
         [0044]     The height of the cylindrical refill bar  15  can be adjusted according to different refill rate requirements. This adjustment can be implemented by adjusting the threads or any other ways. At least one refill orifice  151  is set at the bottom of the refill bar  15 . In addition, the normal pressure water release hole  16  is set in the sidewall of the upper section of the outlet  12 . The ring shaped checked valve  17  is set in the ring area between the outlet  12  below the normal pressure water release hole  16  and the outlet  14 . This device can discharge the normal pressure water in the ceramic toilet tank  6 . Besides, the inlet  18  is set on the upper section of one side of the pressure water vessel  1 .  
         [0045]     The pressure water vessel  1  is installed inside a ceramic water tank  6 , with external threads on a lower section of the outlet  12  threaded in the inlet of the standard toilet (not shown).  
         [0000]     The Infill Valve  
         [0046]     The infill valve  2  includes a valve body  21 , a valve rod assembly  22 , and a valve support  23 .  
         [0047]     The valve body  21  is a hollow cylinder with an outlet  211  in the front portion and several overflow openings  212  set in the wall panel. A seal gland  213  with a through hole is set in the inner rear portion.  
         [0048]     The valve rod assembly  22  is set in the valve body  21 , including the valve rod  221 , the valve rod spring  222 . The valve rod  221  is hollow inside. A seal component  223  is set in the front portion of the valve rod, forming seal with the valve body  21 . The posterior segment of the valve rod  221  goes through the through hole of the seal gland  213 , forming seal with the seal component  224 .  
         [0049]     The valve support  23  is fixed at the rear end of the valve body  21 . The movable valve support  231  and the spring  232  are set inside the valve support  23 . Pushed by the spring  232 , the movable valve support  231  pushes against the valve rod  221 . The inlet  233  is set in the sidewall of the valve support  23 .  
         [0050]     The assembled fill valve  2  is fixed onto the ceramic water tank  6  with the inlet  233  connected with the charging duct (not shown in the drawing) of the water supply system, and the outlet  211  is connected by hose with the inlet duct  31  of the combination valve  3  described below.  
         [0051]     The infill valve  2  also has the function of pressure stabilizer. Namely, when the pressure in the pressure water vessel  1  is higher than the set value, the inner pressure will be released through the overflow outlet  212  of the infill valve  2  into the ceramic toilet tank  6  until the pressure in front of the infill valve  2  is equal to that of the rear. The structure and the stabilizing process is the same as the technology of the previous application, and will not be described here.  
         [0000]     The Combination Valve  3   
         [0052]     Inside the combination valve are set an inlet duct  31 , an anti-siphon ball valve  32 , a check valve  33 , an outlet duct  34 , a spout  35 , a flush control valve  36 , an air-in valve  37 , and an outlet  39  connecting the flush valve  4  and open valve  5 . Among these:  
         [0053]     The inlet duct  31  is connected with the infill valve  2 .  
         [0054]     The anti-siphon ball valve  32  is set on the upper section of the inlet duct  31 . When the inlet duct  31  is filled with pressurized water, the anti-siphon valve  32  closes; when the pressure in the water supply system is equal or lower than the atmospheric pressure, the anti-siphon valve  32  opens.  
         [0055]     The check valve  33  is set in the channel between the inlet duct  31  and the outlet duct  34 . When the pressure in the outlet duct  34  is higher than that in the inlet duct  31 , the check valve  33  closes, otherwise, opens.  
         [0056]     The bottom of the outlet duct  34  is connected with the inlet  18  of the pressure water vessel  1 . Inside the outlet duct  34  is set the spout  35 , the lower end of which is set as a conic necking segment.  
         [0057]     Above the outlet duct  34  is set the pressure-controlled switch  36 , which includes the infill cavity  361 , the water pressure cavity  362 , the infill piston  363  and the pressure-controlled spring  364 . The infill cavity  361  is connected with the check valve  33 . A partition  30  with a through hole is set between the infill cavity  361  and the water pressure cavity  362 .  
         [0058]     The infill piston  363  is set inside the water pressure cavity  362 .  
         [0059]     The piston rod  365  of the infill piston  363  goes through the through hole  301 , and, with the push of the pressure-controlled spring  364 , reaches into the spout  35  inside the outlet duct  34 . An the seal component  366  set at the ending of the pressure-controlled spring  364  forms seal with the spout  35 .  
         [0060]     The air-in ball valve  37  is set in the ring chamber between the outlet duct  34  and spout  35 . The air-in ball valve  37  and the spout  35  form an air-in device.  
         [0061]     The outlet  39  is set on the bottom sidewall of the water pressure cavity  362 , and is connected with the inlet  411  of the flush valve  4 , and then connecting the inlet  52  of the open valve  52 .  
         [0062]     In addition, the piston rod  365  and the through hole  362  are a small gap fitting-in. Namely, when the infill piston  363  closes, the pressurized water can goes slowly through the small gap from the infill cavity  361  to the water pressure cavity  362 . The fitting-in with small gap has various kinds of structure, but this is not the major point of the present invention, and will not be further described. As shown in the drawing, this small gap fitting-in is to open a small cross-section V groove on the piston rod  365 .  
         [0000]     The Flush Valve  4   
         [0063]     The flush valve is set through inside the pressure water vessel  1 , and forms seal with the pressure water vessel  1 . The flush valve  4  includes a hollow valve body  41 , a big piston  42 , an upper cylinder sleeve  43 , a small piston  44 , and a spring  45 . Among these:  
         [0064]     Above the valve body  41  are set the inlet  411  and outlet  412  (The drawing is just a diagrammatical sketch, in which the inlet  411  and outlet  412  are shown as one part.); the valve body  41  is placed inside the pressure water vessel  1  through the opening  11  on its top; the bottom of the valve body is fixed on the locating plate  13  in the pressure water vessel  1 . The inlet  411  is connected with the outlet  39  of the combination valve  3 ; the outlet  412  is connected with the inlet  52  of the below described open valve  5 . Above the valve body  41  is set a normal pressure orifice which is connected with the outside; inside the middle of the valve body  41  is set a partition  414  with a through hole.  
         [0065]     The big piston  42  is set sliding below the partition  414  inside the valve body  41 . The seal component  422  seals the space between the partition  414  and the big piston  42 , forming the lower cavity  46 . A protruding plate  421  with smaller diameter is set at the bottom of the big piston  42 . A seal component  423  is set at the bottom end of the protruding plate  421 . This seal component  423  can be pushed onto the top of the outlet  14  and seals it.  
         [0066]     The upper cylinder sleeve  43  is fixed above the partition  414  in the valve body  41 , with an inlet and an outlet, which are connected respectively with the inlet  411 , and the outlet  412  of the valve body  41 . In the middle of the upper cylinder sleeve  43  is set a water release tube  431 , which is directly connected with the outlet  14  of the pressure water vessel  1 . A check valve  432  is set inside the water release tube  431 .  
         [0067]     A small piston  44  is fixed above the partition  414  inside the valve body  41 , with the upper part set sliding inside the upper cylinder sleeve  43 , forming seal by the seal component  441  with the upper cylinder sleeve  43 . A seal component  442  below the small piston  44  can be pushed onto the through hole of the partition  414  of the valve body  41 . Besides, at the bottom of the small piston  44  is an opening  443  connecting with the lower cavity  46 .  
         [0068]     The spring  45  is set between the upper cylinder sleeve  43  and the small piston  44 . And, the upper cavity  47  is formed between the upper cylinder sleeve  43  and the small piston  44 ; the normal pressure cavity  48  is formed above the partition  414  of the valve body  41  and around the upper cylinder sleeve  43  and the small piston  44 .  
         [0000]     The Open Valve  5   
         [0069]     On the body  51  of the open valve  5  is set an inlet  52 , which is connected with the outlet  412  of the flush valve  4 . On the body  51  is also set a water release hole  53 , which is connected through a tube with the normal cavity  48  of the flush valve  4 , and then with the water release tube  431  of the flush valve  4 . Inside the open valve  5  is set a spring  54  and a handle  55  (or a push button). With the push of the spring  54 , a side of the handle  55  can cover and seal the inlet  52  of the body  51 .  
         [0070]     The open valve  5  can be installed on sidewall of the ceramic tank  6 , forming a side-push structure. If the handle  55  is changed into a push button, the open valve  5  can be installed on the top of the ceramic tank  6 , forming a top-push open button.  
         [0000]     Working Principle  
         [0071]     As shown in  FIG. 1 , the pressurized flush system described in the present invention is in a static state, in which the water level in the pressure water vessel  1  reaches a certain value, and the air in it is compressed. When the pressure in the pressure tank  1  reaches the set value, the infill valve  2  shuts off, and the inlet  18  of the pressure water tank  1  does not fill water any more. Pressure in the pressure-controlled switch  36  of the combination valve  3  and that in the upper cavity  46  and lower cavity  47  of the flush valve  4  come to a balance under normal pressure. The infill piston  363  is at the highest position (open state); the big and small piston  42  and  44  of the flush valve  4  are at the lowest position (closed state); the anti-siphon ball valve  32  and the air-in ball valve  37  inside the combination valve  3  closes with the effect of the water pressure and the check valve  33  is at the open state; and, besides, the open valve  5  is at the closed state, namely, with the push of the spring  54 , one side of the handle  55  covers and seals the inlet  52  of the valve body  51 .  
         [0072]     As shown in  FIG. 2 , when to flush the toilet, press the handle  55  of the open valve  5 , making the inlet  52  open, and the pressurized water in the upper cavity  47  of the flush valve  4  flows into the open valve  5 , and then flows through the outlet  53  of the open valve  5  back into the normal cavity  48  of the flush valve  4 , with which the pressure in the upper cavity  47  of the flush valve  4  goes down. Now the pressure in the lower cavity  46  of the flush valve  4  is higher than that in the upper cavity  47 , so the pressure in the lower cavity  46  will push the small piston  44  to go up, making the pressurized water in the lower cavity  46  go through the ring channel around the upper cavity  47  into the normal cavity  48 .  
         [0073]     Then the big piston  42  is effected at the bottom by the pressure in the pressure water vessel  1  and goes up, making the outlet  14  of the pressure water vessel  1  open, and starting to flush the toilet. Meanwhile, as the open valve  5  is connected with the water pressure cavity  362  of the pressure-controlled switch  36  in the combination valve  3 , the pressure in the water pressure cavity  362  disappears.  
         [0074]     With the effect of the spring  364 , the infill piston  363  falls rapidly, and covers and seals the spout  35 , closing the inlet  18  of the pressure water vessel  1 , and reaches the purpose of not infilling water into the pressure water vessel when flushing. Besides, during the course of flushing the toilet, the resistance pressure makes the pressure in the water release tube  431  of the flush valve  4  increase, pushing the check valve  432  in the water release tube  431  to ascend, and thus preventing water in the toilet flows into the normal pressure cavity. And at the same time, water flowing from the upper cavity  47  of the flush valve  4  and the water pressure cavity  362  of the pressure-controlled switch  36  through the open valve  5 , and that from the lower cavity  46  of the flush valve  4  is stored temporarily in the normal pressure cavity  48 .  
         [0075]     As shown in  FIG. 3 , when the water level in the pressure water vessel  1  goes down to the top of the refill bar  15 , the big-area outlet  14  is exposed in the compressed air in the pressure water vessel  1 . The compressed air flushes rapidly out of the outlet  14  of the pressure water vessel  1 , and pushes the water flow in the toilet channel, which reaches the performance of a high-speed flush of the posterior water flow, and making the posterior flush still as strong.  
         [0076]     As shown in  FIG. 4 , as now the pressure water vessel  1  is under normal pressure, with the work of gravity the water below the refill bar  15  flows slowly into the toilet, forming water seal, and the whole process from flushing to refill is completed. Now as the pressure in the toilet channel is restored into normal pressure, the check valve  432  inside the water release tube  431  of the flush valve  4  falls down, the water stored in the normal pressure cavity during flushing flows through the water release tube  431  into the toilet.  
         [0077]     As shown in  FIG. 5 , during the process of flushing and refill, as the open valve  5  has closed, the pressure in the pressure water vessel  1  disappears, and the valve rod  221  of the infill valve  2  opens itself by the effect of the spring  222 .  
         [0078]     The pressurized water from the water supply system flows through the hollow valve rod  221  into the pressure-controlled switch  36 . A small portion of this pressurized water flows through the V shaped groove in the piston rod  365  of the infill piston  363  into the water pressure cavity  362 , and then into the upper cavity  47  of the flush valve  4 , and next through the opening  443  in the bottom of the small piston  44  into the lower cavity  46 , and pushes the big piston  42  to close.  
         [0079]     As the cross section of the opening  443  in the bottom of small piston  44  is bigger than that the V shaped groove on the piston rod  365  of the infill piston  363 , the water pressure in the water pressure cavity  362  of the combination valve  3  cannot increase until the small piston  42  and the big piston  44  of the flush valve  4  close. And then this water pressure overcomes the action force of the spring  364 , making the infill piston  363  ascend, and opening the inlet  18  of the pressure water vessel  1 . Now the major portion of the pressurized water from the water supply system flows through the spout  35  into the pressure water vessel  1 .  
         [0080]     During the initial process of the infilling water, as the pressure water vessel  1  is under a normal or law pressure state, the pressure difference between the back and front of the spout  35  is comparatively big, and as the front of the spout  35  is set as a conic necking segment, the speed of the water flowing through the spout  35  is very high.  
         [0081]     The high-speed water column makes the ring chamber around the conic necking segment become vacuum, namely produce a Venturi effect. The atmospheric pressure pushes the air-in ball valve  37  open; air is carried into the pressure water vessel  1 .  
         [0082]     With the water level in the pressure water vessel  1  going up, the pressure goes up as well, and the Venturi effect disappears; the air-in ball valve  37  closes with the effect of the pressure in the pressure water vessel  1 .  
         [0083]     Now the pressurized water from the water supply system continues flowing into the pressure water vessel  1  until the pressure in the pressure water vessel reaches a certain value, and then the infill valve  2  closes. The water infill process is completed, and the whole flush system restores to the static state.  
         [0084]     Although there has been hereinabove described a specific pressurized flush system in accordance with the present invention for the purpose of illustrating the manner in which the invention may be used to advantage, it should be appreciated that the invention is not limited thereto. That is, the present invention may suitably comprise, consist of, or consist essentially of the recited elements. Further, the invention illustratively disclosed herein suitably may be practiced in the absence of any element which is not specifically disclosed herein. Accordingly, any and all modifications, variations or equivalent arrangements which may occur to those skilled in the art, should be considered to be within the scope of the present invention as defined in the appended claims.

Summary:
A pressurized flush system includes a pressure water vessel having an inlet and an outlet. An infill valve, an open valve, and a flush valve are provided with the flush valve disposed within the pressure vessel and in fluid communication with the infill valve and the open valve. The flush valve includes a hollow valve body and cooperating pistons controlling water discharge from the water vessel outlet. The cooperating pistons are disposed within the hollow valve body.