Toilet flush water opening device provided with an electrohydraulic actuator

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.