The previous technology consisted of two basic types : A) The"delayed closure"flush valve has input and output connections of equal diameters; the input and output outflows are therefore equal. On being operated, the valve opens, releasing the water. To reduce the damage of the hydraulic impact that occurs when, in closing, the speed of the fluid is rapidly converted into pressure energy, the conventional valve possesses a system that delays closure. For the inflows and the outflows of the"delayed closure"flush valve to be equal, a large diameter supply from the water tank is required and cannot be directly supplied from the mains since the tubing into the houses is, normally, of insufficient diameter.

B) The other option, the cistern, on being operated, opens a valve, releasing the stored water to the sanitary vessel. This cistern possesses a ball cock that is closed when the cistern is full. It does not introduce hydraulic impact into the system, nor does it demand large diameter tubing and can be supplied directly from the mains.

The CAPACITY FLUSH SYSTEM FOR SANITARY VESSELS, focus of the invention under consideration, consists of a-pressure vessel (2) that is constantly full of water under direct pressure from the hydraulic system, an air vent (3) that limits the upper level of the water and'a user-operated valve (1) that releases the water into the sanitary vessel and which is automatically closed.

This invention combines the advantages of"delayed closure"flush valves and of water cisterns without incorporating their disadvantages: A) The CAPACITY FLUSH SYSTEM can be opened and dosed quickly without the inconvenience of hydraulic impact. The zdelayed closuren flush valves are the main sources of strong dynamic oscillations in the hydraulic systems in buildings. The fact that the present CAPACITY FLUSH SYSTEM

does not produce impact in the hydraulic system results in lower requirements in relation to its mechanical resistance when dimensioning the tubing.

B) The fact that the CAPACITY FLUSH SYSTEM has no delay in the closure results in significant water economy.

C) When a"delayed dosure"valve is opened, in the initial moments of acceleration, the water is launched without pressure into the sanitary vessel, lacking sufficient energy to cause cleaning'. This amount of liquid is, therefore, wasted. The CAPACITY FLUSH SYSTEM is installed dose to the sanitary vessel. It is not, therefore, necessary to accelerate large water masses. This results in water economy.

D) By not having internal components that require maintenance, as in the case of cisterns, the pressure vessel can be set at a high point in the wall. The water thus flows more quickly, since it has the necessary pressure. This also results in water economy.

E) Given the good distance attainable between the pressure chamber and the sanitary vessel, the water discharge will occur directly and uniformly independent of the floor of the building or the inlet water pressure.

F) This distance also results in larger mechanical energy per volume of water, which makes the cleaning more efficient and it results in lower water consumption per operation.

G) This same factor also dispenses with the need or special arrangements for sanitary vessels, so that they can work under tow pressure, as in the case of shared cisterns.

H) This CAPACITY FLUSH SYSTEM can be fed by means of small-diameter tubing and components. As the refilling occurs gradually, the incidence or "weight"in te calculation of the diameter of the hydraulic system is lower, which will result in substantial reductions in the diameters and costs throughout the system.

1) The absence of pressure oscillations in the hydraulic system guarantees more comfortable bathing in the case where the water heating is of the

centralised type. Thus the construction of an exclusive hydraulic installation for the sanitary vessels, which is usually very costly, can be dispensed with.

J) The filling of the pressure chamber (2) is moderate, but not as slow as in the case of water cisterns, in which the outflow is limited by the small opening in the ball cock. In this way re-filling, although gradual, is fast enough not to be routinely perceived by the user.

K) The CAPACITY FLUSH SYSTEM can be installed within the internal part of the walls in order to become invisible, like the"delayed closure"flush valve, satisfying the hygiene requirements, the use of space and appearance. The fact that this flush system does not possess internal components, such as a ball cock, a siphon or rubber gaskets means there are no intenal iterns requiring maintenance.

L) Because of its construction features, the CAPACITY FLUSH SYSTEM will operate well under a wide range of pressures, from a water column of a few centimetres to the direct pressure from the mains.

M) As the CAPACITY FLUSH SYSTEM is permanently connected to the hydraulic system and since the valve contains within it an air cushion under pressure (7), this will absorb blows generated in other components connected to the same hydraulic installation.

N) The existence of an air vent (3) at the upper extremity prevents the aspiration of the content of the sanitary vessel in the event of negative pressure in the hydraulic system (4). In this eventuality, the vent will open instantly, allowing outside air into the interior of the hydraulic system. (4), preventing the negative pressure from reaching the outlet tubing (5) and therefore the sanitary vessel.

O) The automatic return valve (1) may be of the pedal type because the re-flux will not occur. under negative pressures.

P) If the option is for installing the automatic return valve (1) in the section of the outlet tubing between the wall and the sanitary vessel, it is guaranteed that there will be no maintenance-dependent part within the wall, as the air vent (3) is entirety accessible by removing the cover and unscrewing it.

Q) As the water inside the pressure container (2), at the moment of opening, remains under pressure from the air cushion (7), this gives the water an extra impulse, besides that of gravity, which means that it is forced into the sanitary vessel, reaching the maximum flow rate in the minimum time. The effect of this impulse is to make the siphoning of the vessel start more quickly and this will also imply in lower water consumption.

R) This initial impulse also has a positive effect on the transportation of detritus within the sewage systems.

In FIGURE 1 we see the CAPACITY FLUSH SYSTEM FOR SANITARY VESSELS in section, representing the operated valve for the user, with automatic return to the normal closed position (1), the pressure chamber (2), the air vent (3), the narrow diameter hydraulic system feed (4), the large diameter discharge tubing (5), and the sanitary vessel (6). We also see the hydraulic impact absorber consisting of an air cushion (7) in the upper portion of the pressure chamber (2), and also the ventilation and outflows draining tubing (8) that connects the air vent (3) chamber to the discharge tubing (5), on its portion beyond the user-operated valve (1).

The CAPACITY FLUSH SYSTEM FOR SANITARY VESSELS, object of the invention, consists basically of joining together a user-operated valve, with automatic return to the closed position (1), a pressure chamber (2), and an air vent (3). The pressure chamber is constantly supplied with water direcdy from the narrow diameter hydraulic feed system (4) that enters the pressure chamber (2) at its lower portion. The air vent (3) is installed at the top of the pressure chamber in such a way as to vent atmospheric air in both directions, in and out of the pressure chamber. The air vent (3) will prevent the outflow of water from the pressure chamber (2) when this reaches the maximum level. A large diameter discharge tubing (5) exits from the lower portion of the pressure chamber (2) and is connected to the sanitary vessel (6) by means of the i, automatic return valve (1). The automatic return valve (1) can be of the fast return type, for the velocity in the closure does not produce a hydraulic impact in the feed system (4).

Right after the system is installed, when opening the main valve, the pressure chamber (2) will gradually fill with water fed by a narrow diameter tube (4). When the water reaches the top of the pressure chamber (2) the air vent wi ! t dose and the water wit stop flowing. At this moment the chamber pressure will be raised and it will quickly equalise to the pressure of the feed system (4).

The CAPACITY FLUSH SYSTEM will be full and ready for use. This operation takes some seconds. On opening the automatic return valve (1), the water in the pressure chamber will start to descend en route to the sanitary vessel ... making the pressure in the pressure chamber (2) fall rapidly. The air vent (3) will open automatically allowing the surrounding air to flow to the interior of the pressure chamber (2), occupying the space set free by the water, thus preventing its flow being inhibited by the ensuing vacuum. The stored water will flow down through gravity and will clean the sanitary vessel. From the instant when the pressure in the interior of the pressure chamber (2) falls, the water wi ! ! start to flow from the system (4) to the interior of the pressure chamber (2) and as soon as the automatic return valve (1) doses, a new re-filling process will be initiated. When the level reaches the top of the pressure chamber (2) causing I i the locking of the air vent, a new cycle will have been concluded.

The air cxushion (7) located in the upper part of the pressure chamber (2) makes the damping of the hydraulic impact effect more efficient when the air vent (3) obstructs the passage. This cushion (7) will be attainable as a result of the disposition of the exit point for the air vent (3) a little below the top of the pressure chamber (2). After a discharge, the pressure chamber (2) will be gradually filled with water, this being fed by a narrow tube (4). When the water reaches the top of the pressure chamber (2) the air vent (3) will be dosed and the water will stop flowing. Although the water flow is less, this closure could still be responsible for the induction of a lower intention hydraulic impact in the feed system (4), this problem being overcome by the inclusion. of the air cushion (7) in the upper portion of the pressure chamber (2).

The ventilation and outflows draining tubing (8) that connects the air vent (3) to the discharge tubing (5), in its portion beyond the user-operated valve (1), functions as a release to the sanitary vessel (6) of any eventual

outflow of the air vent (3), and also allows for the draining of the fluid that could be retained in this section of the discharge tubing (5) beyond the user valve (1) after its closure, allowing this water to fulfil its function, by admitting ambient air to flow inside the discharge tubing (5).

Independently of the quality of air vent (3), it will be liable to leakage.

The ventilation and outflow draining tubing (8) will allow this small amount of liquid to flow from the air vent (3) chamber to the discharge tubing (5), in its portion beyond the user-operated valve (1), preventing it from spilling down the wall. This same tubing (8) will also fulfil another function, allowing for the complete drainage of the water from the lower portion of the discharge tubing (5) after the user-operated valve (1) closes. Were it not for this, the atmospheric pressure would retain some water in this section of the discharge tubing (5).

Depending on the type of sanitary vessel (6), this retained water would gradually flow down, as some air would enter the discharge tubing (5), causing an unpleasant noise and, for lack of energy, this amount of water would be wasted. The proposed tubing (8) will allow for this water to fulfil its function after the closure of the user-operated valve (1) which will bring positive consequences in terms of economy, as well as a decrease in noise disturbance.