Patent ID: 7581263

Claim:
A toilet flush opening device ( 10 ), comprising: a water cistern ( 12 ); a valve, supplying the water cistern, connected to a water supply system, openable to allow the cistern ( 12 ) to be filled with water if a water level in the cistern ( 12 ) drops below a predetermined lower limit; a lower discharge aperture ( 14 ) at a bottom of the cistern ( 12 ); a vertical moveable discharging open/close element ( 16 ) over the aperture ( 14 ), configured to occupy i) a closed lower position to keep the water in the cistern ( 12 ), and ii) an open upper position to discharge the water from the cistern ( 12 ) into a toilet bowl, the open/close element ( 16 ) comprised of a tubular vertical casing ( 24 ), the tubular vertical casing ( 24 ) having an upper face ( 40 ) and a lower end ( 26 ), the lower end ( 26 ) comprised of an open/close element seat ( 28 ) coinciding with the lower discharge aperture ( 14 ); an electrohydraulic actuator ( 18 ) comprised of a controlled solenoid valve ( 20 ) and an expandable hydraulic device ( 22 ), the expandable hydraulic device ( 22 ) supplied by the solenoid valve ( 20 ) and connected mechanically to the open/close element ( 16 ); and a sliding actuating rod ( 32 ) mounted inside the tubular vertical casing ( 24 ) and having a lower first end and an upper second end, the lower first end comprising an open/close element seat seal ( 34 ), and the upper second end, having a horizontal shoulder element ( 44 ) mounted immediately proximate to an uppermost end of the upper second end, projecting from the tubular vertical casing ( 24 ), the upper second end configured to be actuated by the expandable hydraulic device ( 22 ) to actuate the open/close element seal ( 34 ), wherein the solenoid valve ( 20 ) is configured to occupy an inactive position and an active position, the solenoid valve ( 20 ) configured to deliver water at pressure when the active position is occupied, wherein the hydraulic device ( 22 ) is moveable between a retracted position and an extended position, the expandable hydraulic device ( 22 ) i) not supplied by the solenoid valve ( 20 ) and not moving the open/close element ( 16 ) when the hydraulic device ( 22 ) is in the retracted position, and ii) the expandable hydraulic device ( 22 ) supplied with water at pressure by the solenoid valve ( 20 ) and tending to move the open/close element ( 16 ) from the closed lower position to the open upper position when the hydraulic device ( 22 ) is in the extended position, and wherein the expandable hydraulic device ( 22 ) is mounted on the upper face ( 40 ) of the tubular casing ( 24 ), and comprises at least one moveable upper actuating face ( 42 ), the at least one moveable upper actuating face ( 42 ) configured to apply an actuating force to the shoulder element ( 44 ) of the upper second end ( 38 ) of the actuating rod ( 32 ) when the expandable hydraulic device ( 22 ) is in the extended position.