Lavatory unit

Abstract

A lavatory unit ( 10 ) comprising a tank body ( 12 ) connected to a pressurised water supply ( 20 ), and flushing means ( 14, 21, 23 ) for releasing water from the tank body via an outlet to a lavatory bowl ( 11 ). The flushing means includes an elastic bladder ( 21 ) the interior of which is in communication with the tank, the tank being generally sealed otherwise, such that the bladder stressed with the expansion of air forced from the tank as the tank fills with water and the bladder relaxes elastically as the tank empties, and thereby assists in ejecting the water under pressure from the tank to provide a better flushing action.

1 . A lavatory tank comprising a tank body, means for connecting the tank body to a pressurised liquid supply, and means for releasing liquid from the tank body via an outlet, wherein said releasing means comprises an elastic means which becomes stressed as the tank fills with liquid and which becomes relaxed as the tank empties. 
     
     
         2 . A lavatory tank according to  claim 1 , wherein said elastic means comprises an expandable-contractible member defining an internal space which is in communication with the interior of the tank, whereby as liquid fills the tank it displaces gas from the empty tank to expand the said internal space. 
     
     
         3 . A lavatory tank according to  claim 2 , wherein said expandable-contractible member is chosen from one of the following: a flexible elastic bladder, a concertina-like flexible member. 
     
     
         4 . A lavatory tank according to  claim 2 , wherein said expandable-contractible member is mounted within a support housing, said support housing defining an internal chamber, said internal chamber defining the maximum expansion of said expandable-contractible member. 
     
     
         5 . A lavatory tank according to  claim 4 , wherein at least one aperture is defined on said support housing, said at least one aperture extending from said internal chamber of said support housing to the exterior of said support housing. 
     
     
         6 . A lavatory tank according to  claim 1 , wherein said lavatory tank further comprises a four way ball valve, said means for connecting the tank body to a pressurised liquid supply coupled to said ball valve, said releasing means further coupled to said ball valve. 
     
     
         7 . A lavatory tank according to  claim 1 , wherein said releasing means further comprises a sluice valve coupled to said outlet. 
     
     
         8 . A lavatory unit comprising a tank according to  claim 1 , and a lavatory bowl connected to the tank via the tank outlet. 
     
     
         9 . A lavatory unit according to  claim 8 , wherein the bowl comprises a substantially cylindrical section and a flared section, said cylindrical section adapted to hold a volume of water in normal use, said flared section extending from a narrow diameter portion, defined by the top of the cylindrical section, to a wide diameter portion, defined by the mouth of the bowl. 
     
     
         10 . A lavatory unit according to  claim 9 , wherein the water level is maintained in normal use in the cylindrical section at least 5 cm below the flared section. 
     
     
         11 . A lavatory unit according to  claim 9 , wherein said cylindrical section is coupled to a U-bend trap. 
     
     
         12 . A lavatory unit according to  claim 9 , wherein said lavatory unit further comprises a trap-door, said cylindrical section coupled to said trap door. 
     
     
         13 . A lavatory unit according to  claim 9 , wherein the ratio of the height of said cylindrical section to the height of said flared section is between 4:3 to 5:3, wherein the angle of incline of said flared section is between 30°-40°, and wherein said tank outlet enters into the flared section of said bowl at an angle of between 5°-15°. 
     
     
         14 . A lavatory unit according to  claim 13 , wherein the height of said cylindrical section is approximately 23 cm, wherein the height of said flared section is approximately 15 cm, wherein the tank outlet comprises a tube having a diameter of approximately 3 cm, the angle of entry of said tube into said flared section approximately 10°, and wherein the angle of incline of said flared section varies from 37° at that portion of the flared section immediately adjacent the point of entry of said tube into the flared section to 35° at that portion of the flared section directly opposite the point of entry of said tube into the flared section.