Dual-trap toilet having improved pressurization and flushing

Abstract

A toilet assembly may comprise a toilet tank to hold flush water, a flush valve assembly positioned in the toilet tank, a trapway in flow communication with the toilet bowl, a container positioned in the toilet tank, and a connecting tube extending from an interior of the container to the trapway. Between flush cycles, the tank may store a volume of flush water. The flush water may be divided between different regions of the tank that are defined by the structure of the container. Between flush cycles, the container and the trapway may contain pressurized air. A force exerted by pressurized air in the trapway on water in a lower trap may cause an upstream water level in the lower trap to be lower than a downstream water level in the lower trap.

1 . A toilet assembly, comprising
 a toilet tank to hold flush water;   a flush valve assembly positioned in the toilet tank;   a toilet bowl;   a trapway in flow communication with the toilet bowl;   a container positioned in the toilet tank, and   a connecting tube extending from an interior of the container to the trapway,   wherein:
 the container is in flow communication with the toilet tank, the container having an open lower end and a closed upper end, wherein the upper end of the container contains a first portion of pressurized air when the toilet assembly is between flush cycles, 
 the trapway comprises a sump trap, a first upstream weir, a lower trap, and a second downstream weir, and 
 the connecting tube is coupled to the trapway at a position between the sump trap and the lower trap, and provides flow communication between the container and the trapway, and 
 the trapway contains a second portion of pressurized air when the toilet assembly is between flush cycles, wherein a volume of the first portion of pressurized air is less than 30% of a volume of the second portion of pressurized air. 
   
     
     
         2 . The toilet assembly of  claim 1 , wherein, between flush cycles, the first portion of pressurized air is positioned above flush water in the container. 
     
     
         3 . The toilet assembly of  claim 1 , wherein, upon discharging water into a flush valve core to initiate a flush cycle, reduced pressure is created in one or both of the first portion of pressurized air and the second portion of pressurized air. 
     
     
         4 . The toilet assembly of  claim 1 , wherein, upon re-filling the toilet tank with water to end a flush cycle, increased pressure is created in one or both of the first portion of pressurized air and the second portion of pressurized air. 
     
     
         5 . The toilet assembly of  claim 1 , wherein, between flush cycles, the first portion of pressurized air and the second portion of pressurized air are pressurized at a pressure greater than or equal to 0.5 cm of water above atmospheric pressure and less than or equal to 5 cm of water above atmospheric pressure. 
     
     
         6 . The toilet assembly of  claim 1 , wherein the first upstream weir is positioned above a highest point of a trapway inlet by an offset distance of greater than or equal to 2 inches. 
     
     
         7 . The toilet assembly of  claim 1 , wherein the first upstream weir is positioned at point that, between flush cycles, is vertically higher than a water seal of the toilet bowl by a distance of greater than or equal to 0.2 inches. 
     
     
         8 . The toilet assembly of  claim 1 , wherein the flush valve assembly comprises a valve body extending from a valve inlet to a valve outlet and a valve cover having a seal to enclose the valve inlet. 
     
     
         9 . The toilet assembly of  claim 1 , wherein the container comprises a continuous side wall, an upper end wall, and an inner wall that together bound a vacuum chamber of the container. 
     
     
         10 . The toilet assembly of  claim 9 , wherein the inner wall bounds an inner chamber of the container. 
     
     
         11 . The toilet assembly of  claim 9 , wherein a vertical distance between a top surface of the connecting tube and an inner surface of the upper end wall is greater than or equal to 10 mm and less than or equal to 35 mm. 
     
     
         12 . The toilet assembly of  claim 1 , wherein an internal diameter of the connecting tube is greater than or equal to 12 mm and less than or equal to 20 mm. 
     
     
         13 . The toilet assembly of  claim 1 , wherein, between flush cycles, a vertical distance between a top surface of the connecting tube and a water level in the toilet tank is greater than or equal to 45 mm and less than or equal to 55 mm. 
     
     
         14 . A toilet assembly, comprising
 a toilet tank to hold flush water;   a flush valve assembly positioned in the toilet tank;   a toilet bowl;   a trapway in flow communication with the toilet bowl;   a container positioned in the toilet tank, and   a connecting tube extending from an interior of the container to the trapway,   wherein:
 the container is in flow communication with the toilet tank, the container having an open lower end and a closed upper end, 
 the trapway comprises a sump trap, a first upstream weir, a lower trap, and a second downstream weir, and 
 the connecting tube is coupled to the trapway at a position between the sump trap and the lower trap, and provides flow communication between the container and the trapway, and 
 the trapway contains pressurized air when the toilet assembly is between flush cycles, wherein the pressurized air in the trapway exerts force on water in the lower trap such that an upstream water level in the lower trap is lower than a downstream water level in the lower trap by an offset distance of greater than or equal to 15 mm between flush cycles. 
   
     
     
         15 . The toilet assembly of  claim 14 , wherein, between flush cycles, the container comprises pressurized air positioned above flush water. 
     
     
         16 . The toilet assembly of  claim 14 , wherein, upon discharging water into a flush valve core to initiate a flush cycle, reduced pressure is created in pressurized air in the trapway. 
     
     
         17 . The toilet assembly of  claim 14 , wherein, re-filling the toilet tank with water to end a flush cycle, increased pressure is created in the pressurized air in the trapway. 
     
     
         18 . A toilet assembly, comprising
 a toilet tank;   a flush valve assembly positioned in the toilet tank;   a toilet bowl;   a trapway in flow communication with the toilet bowl;   a container positioned in the toilet tank, wherein the container comprises an inner chamber and a vacuum chamber, and   a connecting tube extending from an interior of the container to the trapway,   wherein:
 the container is in flow communication with the toilet tank, the container having an open lower end and a closed upper end, 
 the trapway comprises a sump trap, a first upstream weir, a lower trap, and a second downstream weir, and 
 the connecting tube is coupled to the trapway at a position between the sump trap and the lower trap, and provides flow communication between the container and the trapway, and 
 during a flush cycle, the toilet assembly flushes a volume of flush water, wherein: 
 a first portion of the volume of flush water is stored in the tank prior to the flush cycle; 
 a second portion of the volume of flush water is stored in the vacuum chamber prior to the flush cycle; 
 a third portion of the volume of flush water is stored in the inner chamber prior to the flush cycle, wherein the third portion is greater than or equal to 40% of the volume of flush water. 
   
     
     
         19 . The toilet assembly of  claim 18 , wherein the first portion is less than or equal to 20% of the volume of flush water. 
     
     
         20 . The toilet assembly of  claim 18 , wherein the second portion is less than or equal to 40% of the volume of flush water. 
     
     
         21 . The toilet assembly of  claim 18 , wherein, between flush cycles, the container comprises pressurized air positioned above flush water in the vacuum chamber. 
     
     
         22 . The toilet assembly of  claim 18 , wherein, upon discharging water into a flush valve core to initiate a flush cycle, reduced pressure is created in pressurized air in the trapway. 
     
     
         23 . The toilet assembly of  claim 18 , wherein, upon re-filling the toilet tank with water to end a flush cycle, increased pressure is created in pressurized air in the trapway.