Adjustable-volume metering pump automatic dispenser device   

BACKGROUND OF THE INVENTION

The present invention relates to an adjustable-volume metering pump automatic dispenser which is mounted in a toilet cistern in order automatically, each time the toilet is used and at the end of the flush cycle, to dispense a dose of sanitary product that is prediluted, regulated and suited to the volume of water, in order to clean, disinfect and deodorize the toilet bowl.

The cleaning and disinfection of private and communal toilet bowls in companies, restaurants, hotels, holiday sites and centers, public establishments, hospitals and clinics, medico-social establishments, regularly require the manual intervention of those tasked with maintenance operations and the frequency of intervention is dependent on the usage: private domestic, communal, intensive. These interventions are time consuming and unpleasant and communal spaces are often smelly with toilet bowls that have been insufficiently cleaned and especially with dubious and sometimes even no, disinfection. Often, a strong smell of deodorizing product coexists with a bad smell of dirty toilets.

The use of a perforated plastic fitting is commonly employed, this being attached to the interior rim of the toilet bowl and containing a pellet containing anti-limescale and anti-odor products, which dissolve with the repeated passage of water, with the aim of sanitizing the toilets.

The disadvantages are great: firstly, these pellets dissolve very quickly as soon as they have been in contact with the water, secondly the flow of the discharged water carries the product of the dissolving operation directly in its wake and sideways to be discharged into the drain in just a few seconds. When it is around about half-used, the pellet dissolves suddenly and in its entirety, creating a strong concentration of product which is completely flushed down the drain as the water is discharged, and very little product remains in the bottom of the bowl; the product never reaches or covers the entire interior surface of the toilet bowl, thus making the hoped-for action extremely insufficient and ineffective, especially with no antibacterial action, although an antibacterial action is one of the basic principles in cleanliness and hygiene. We know that toilets are a hotbed for the growth of germs. Analyses performed have shown that, with the toilet lid open, splashes containing substances with harmful germs in are collected a distance of 1 meter away.

When the plastic fitting becomes accidentally unhooked and drops down into the bottom of the toilet bowl it becomes difficult to recover because even though the product in the pellet has been used up, the plastic fitting has still to be fished out.

There are also in existence single-use effervescent pellets that are placed in the U-bend of the toilet, in order to remove scale and marks, but these products act only in the bottom of the U-bend and on the discharge pipes leading to the drains. The toilet cannot be re-used until the pellet has had a chance to dissolve and to act, and the reuse of the toilet discharges the product into the drain.

A device similar to the above one is also on offer; this is a plastic fitting on which a small bottle of liquid sanitary product is positioned, this bottle being hooked, inverted, on the interior rim of the bowl; the product is supposed to pour out slowly as the water passes, but it does no such thing; the bottle empties very quickly and especially without reaching or coating all of the interior surfaces of the toilet bowl and flushing the toilet in a few seconds systematically in its wake and sideways discharges practically all of the product down the drain; nonetheless, an infinitesimally small proportion of product does remain and its action is limited to the U-bend of the toilet.

Another system proposes linking the toilet seat in with the centralized forced ventilation and extraction system in order to extract unpleasant smells, but this does nothing towards addressing the need for cleanliness and for actually deodorizing the points at which the smells are produced or the unavoidable requirement for disinfection.

Also, there is a device known as a diffuser which is placed in the toilet cistern and equipped with a fixed-capacity metering device operated by a float and suited only to the product of that make; the cleaning product is diluted in all of the toilet cistern water, this dilution being extremely weak, of the order of 1 part in 5000 and what is more, it presupposes the use of a highly concentrated product; the dosage is approximately 2 milliliters to every 8 liters of water on average in a toilet cistern.

The major disadvantage is that the water in the toilet cistern with its small quantity of product is flushed down the drain when the toilet is flushed. Water that discharges in between 3 and 5 seconds can produce no more of an effect than that of the passage of water because ultimately in practice the amount of product that remains in the toilet bowl is actually too small for it to be able to have any effective cleaning or disinfection action. This system allows the low-dosage solution to wash all the surfaces and all of the product is discharged directly down the drain in 4 seconds.

In all of the cases mentioned hereinabove, this amounts to discharging 90% of the products used down the drain, and to attempting to clean, disinfect and deodorize the toilet bowl with the remaining one tenth of the water and product, in a dose that is far to dilute and ill-suited to the remaining volume of water.

Another system on offer is based on a thick and sticky gel which is compressed by hand and driven by a piston in its cylindrical support. This system allow a pellet of this sticky gel to be applied and stuck to the internal wall of the toilet bowl to disinfect and deodorize it. This system is one of the latest products currently to have been marketed and the deodorizing effect does not last as long as the presence of the pellet; as far as disinfection is concerned, the product is subjected to direct and sideways passage of the water and can never reach and cover all the interior surfaces of the bowl. As in all the cases mentioned earlier, everything is discharged down the drain.

Other multifunction products in the form of liquid or powder have been marketed but their use always requires the regular intervention of those tasked with cleaning. This is why one very often finds a notice reading “please leave these toilets as clean as you found them”, or entertaining notices discussing cleanliness and smells at some length and, in the best of cases, a deodorizing spray is made available which does not disinfect anything, and the vaporization of the microparticles of which are known to be hazardous to health.

Professional inspectors are no fools, they make the toilets their first point of call when carrying out an inspection. In the restaurant industry, it is common practice to make a preliminary inspection of the toilets which provides information on which to base an assessment.

SUMMARY

The present invention, the adjustable-volume metering pump automatic dispenser is aimed at addressing and meeting the need presented by the technical problem: regularly cleaning, disinfecting and deodorizing effectively and permanently all of the interior parts of the toilet, made up of: starting from the inside of the cistern, fill and discharge mechanisms, internal piping for the water circuit and especially all of the interior surfaces of the toilet bowl, even those surfaces that are not accessible manually.

The adjustable-volume metering pump of the dispenser allows the volume of the dose of liquid product to be regulated in relation to a determined volume of water and allows this regulated dosage to be maintained throughout the use of the same product for cleaning, disinfecting and deodorizing the toilets. The user can vary the volume of the dose as need be and according to the product, with the possibility of using products that are currently on the market, because each product has its own dosage specifications and protocol.

The adjustable-volume metering pump automatic dispenser can be equipped with two versions of an adjustable-volume metering pump: FIGS. 1 and 3 depict the membrane-pump metering pump version (4c), and FIGS. 2, 4 and 5 depict the piston-pump metering pump version (6a).

For both versions of adjustable-volume metering pump, FIGS. 1 and 2, the operation is the same. The operating cycle is broken down into four phases with respect to the emptying and the filling of the toilet cistern (2). With reference to FIG. 1:

Phase One: From the emptying and discharge of water from the toilet cistern (2), the dispenser allows just 90% of the cistern water to flow away in order to discharge, after use, the content of the toilet bowl with conventional cleaning using a high flow rate of water. During this emptying the water level drops and the float (10) moves down taking with it the membrane (4c), and this allows the sanitary product contained in the reservoir (1) to be drawn up and introduced via the inlet valve (7) into the volume above the membrane (4c) of the metering pump (4), this representing a first technical feature.

Phase Two: Before the end of emptying, when, during the discharge, just 1.5 liters of water remains in the toilet cistern (2), the float (20) fixed to the articulated lever (19) tips and instantly triggers the opening of the valve (17) of the auxiliary reservoir (15) which releases the predilution immediately mixed with the end of the discharge of water from the toilet cistern (2); the regulated and prediluted dose of sanitary product is prepared by the previous cycle in the auxiliary reservoir (15).

It takes 1.5 liters of water, or a depth of 4.5 centimeters of water in the toilet cistern (2), and it is at this precise moment that the opening of the valve (17) is triggered to make up, with the predilution of product, just the right amount of mixture mixed according to the specification of the sanitary product, to sanitize and deodorize the toilet bowl, and this is a second technical feature.

Another of the specifics of the invention is that all of this mixture, consisting of this 1.5 liters of water and the predilution of product, from the toilet cistern (2), allows optimal action of the product as it is the maximum volume of water and the dose of product recommended by the manufacturer that has been calculated so that this final volume corresponds to the volume of the U-bend and is not flushed down the drain so that the mixture collects in the U-bend of the toilet bowl in which it remains until the next time the toilet is used. In its passage from the toilet cistern to the U-bend of the bowl the mixture has covered and coated all of the sensitive interior surfaces of the toilet to which surfaces the product adheres, even surfaces that are manually inaccessible, and this represents a third technical feature.

Phase Three: Phase Three corresponds to the filling of the toilet cistern (2) with water, and the rise in water level submerges the float (20) which, through its action on the articulated lever (19) closes the discharge valve (17) of the auxiliary reservoir (15).

Phase Four: The refilling of the toilet cistern (2) continues, the water level rising and submerging the float (10) and the upthrust applied by the float to the plunger (4d) and to the membrane (4c) causes the sanitary product, introduced during Phase One and contained above the membrane (4c), to be delivered through the outlet valve (8) of its fluidtight duct (8a) then tipped out by the pouring spout (8b) into the top of the auxiliary reservoir (15), the rising of the float (10), of the piston plunger (4d) and of the membrane (4c) stopping when the mounting plate (4e) of the membrane (4c) comes into contact with the end-stop adjusting rod (5) and determining the setting for the volume of the dose, which represents a fourth technical feature.

The toilet cistern (2) has now completely refilled, water fills the auxiliary reservoir (15) via the filling slot above the adjusting slide (21) and prepares, in readiness for the next cycle, the predilution with the dose of sanitary product received from the metering pump (4). This represents a fifth technical feature.

The predilution is prepared in this auxiliary reservoir (15) with the dose of product that has just been transferred and the water contained in this reservoir, this making it easier for the predilution to mix rapidly and more effectively with the end of the discharge next time the toilet is used, and this represents a sixth technical feature.

The use of the automatic dispenser allows the sanitary products to act to their best effect in order to achieve the aim of true cleaning, disinfection, anti-limescale treatment of all the interior surfaces of the toilets and of deodorizing all of this and the room as is done with manual intervention.

After the treatment preparation has, following the emptying of the cistern (2), covered and coated all the sensitive interior surfaces of the toilet, this final volume of treatment preparation is not flushed down the drain and the fact that it is held in the U-bend of the toilet bowl makes the use of a toilet brush, where needed, easier and more effective without any need to resort to a further flushing or find any additional cleaning product.

Current commercially available liquid products propose multi-function treatments that are perfectly suited to and useable in the adjustable-volume metering pump automatic dispenser.

Thus, the present invention contributes to solving the stated technical problems mentioned in the previous chapter “prior art” on page 1, line 6.

FIG. 1 depicts in cross section all of the adjustable-volume metering pump automatic dispenser equipped with the membrane pump (4c) version of metering pump with the form of auxiliary reservoir (15) that is open with a filling slot, shown in-situ inside a toilet cistern (2).

FIG. 2 depicts in cross section all of the adjustable-volume metering pump automatic dispenser equipped with the piston pump (6a) version with the form of auxiliary reservoir (15) that is open with a filling slot, mounted in-situ inside a toilet cistern (2).

FIG. 3 is a detailed cross section of the adjustable-volume metering pump in its membrane pump (4c) version, in the position for filling the reservoir (1) with sanitary product.

FIG. 4 is a detailed cross section through the adjustable-volume metering pump in the piston pump (6a) version in the position for filling the reservoir (1) with sanitary product.

FIG. 5 is a detailed cross section through the adjustable-volume metering pump in the piston pump (6a) version butting against the volume adjusting screw (5), in the position for emptying the dose of sanitary product into the auxiliary reservoir (15).

FIG. 6 depicts how the automatic dispenser is fitted using the filling spout (3), seals (3c) and by tightening nuts (3a), inside the reservoir (1) of the automatic dispenser and on the outside of the toilet cistern (2).

FIG. 7 is a part section through the adjusting slide (21), mounted in the filling slot, in the form of auxiliary reservoir (15) that is open and the water level in the toilet cistern (2).

FIG. 8 is a schematic view in cross section of the form of auxiliary reservoir (15a) that is closed and fluidtight having a sealed cover (16) at its top, with the inlet valve (18) and the entire discharge system comprising the float (20), mounted on the articulated lever (19) and the predilution discharge valve (17).

FIG. 9 depicts how the metering pump is attached to the reservoir (1) of the dispenser. The same fixings are used for both versions of metering pump (4) and (6).

FIG. 10 is a part section showing details of the mounting of the cylindrical pin (12) on the piston (6a) with respect to the oblong recess of the metering pump (6) in FIGS. 4 and 5.

FIG. 11 is a schematic cross section of the form of auxiliary reservoir (15b) that is open with an inlet valve (18), with the discharge device comprising the float (20), mounted on the articulated lever (19) and the predilution discharge valve (17).

With reference to these drawings, the adjustable-volume metering pump automatic dispenser of FIG. 2 is made up the main reservoir (1) that receives and contains the various sanitary products used for sanitizing the toilets, and of the open auxiliary reservoir (15) with filling slot.

The auxiliary reservoir (15) is fixed laterally to the main reservoir (1), it potentially being possible for these two reservoirs to be produced as a single component. The auxiliary reservoir (15) can also be mounted such that it can slide vertically in an adjustable manner against the reservoir (1) with a screw that holds it in position at the set point at which the float (20) triggers the opening of the discharge valve (17) when just 1.5 liters of water remain at the end of discharge.

These two reservoirs are mounted inside the toilet cistern (2) using the ready-made hole that is still free as toilet cisterns come with two holes, so that the water inlet cock can be fixed either on the right or on the left. It is also possible in the case of toilet cisterns in which the water arrives from the bottom or somewhere else to provide fastening systems, using wedging or lateral hooks clamped against the edges of the cistern (2).

A sealed mounting of the main reservoir (1), FIG. 6, against the toilet cistern (2) is performed using the spout (3) via which the reservoir (1) is filled with product, and this mounting is achieved by screwing two nuts (3a) onto the spout (3), one outside the cistern (2) and one inside the reservoir (1), trapping two seals (3c) between them. The spout has a flexible cover (3b) that closes and protects it. The spout may be transparent so that its fullness can be seen at a glance.

The main reservoir (1) has a rigid cover (13) indicating the setting of the volume of the doses using the indexed knob (14) that operates the volume-adjusting rod (5).

In the bottom of this main reservoir (1) there is a vertical cylindrical recess in which the adjustable-volume piston-type metering pump device (6) is mounted, mounting being achieved from underneath using four-point hooking, detail A in FIG. 4 depicted in FIG. 9, or by screwing, not depicted, the base of the metering pump (6) to the reservoir (1). A circular seal (11) seals against the sanitary treatment product present in the upper part and the toilet cistern water in which this metering pump assembly is immersed.

This setup provides a sealed assembly for holding the metering pump in position.

The volume-adjusting end-stop rod (5) is screwed at the top and in the middle of the metering pump (6) into a central tapped through-hole, and screwing the adjusting rod (5) in or out forms the end stop that adjusts the volume of the dose of product; the end-stop position of the adjusting rod (5) thus obtained determines the adjustable upper point of contact of the upper part of the piston (6a), thus limiting its upward movement in order to set the volume of the dose of product of the metering pump (6).

FIGS. 4 and 5 provide information regarding the movement of the piston and the action of the end stop (5) on the piston (6a); a spring (6b) encourages the piston (6a) to move down.

Also provided in the upper part of the metering pump (6) are two other orifices. One is an orifice over which a flap-type or ball-type inlet valve (7) is positioned for taking up and filling with product, using for filling the metering pump (6), the positioning of the inlet valve (7) having to allow pumping from the main reservoir (1) right until the sanitary product is all used up. FIGS. 2 and 4.

The other orifice is used to accept the outlet valve (8), of the flap or ball type, the valve carrier (8c) being connected to a duct (8a) that is sealed and, at the top, connected to the pouring spout (8b) so that on each cycle it supplies a regulated dose of sanitary product into the top of the auxiliary reservoir (15), FIG. 2.

There is an oblong recess across the diameter of the metering pump (6) and the length or inter-axis distance of this recess is slightly greater than the maximum forecast travel of the piston (6a). The piston (6a) is also pierced across its diameter to accept a cylindrical pin (12) which emerges at each end into the oblong recess of the metering pump (6) which guides it. This setup means that the piston (6a) can be left free to move axially by a maximum amount equal to the length of the oblong recess. See FIGS. 4 and 5 and detail in FIG. 10.

On its upper part, the piston (6a) is fitted with a two-way double-lip seal (9) fitted elastically into a circular groove at the top of the piston and the main float (10) is cylindrically force-fitted to its lower part and, each time there is a change in water level in the toilet cistern (2) actuates the piston (6a) within the limits provided by the adjustable position of the end-stop rod (5) of the metering pump (6), the drop in water level causing the downward movement of the float (10) and the piston (6a) which draws treatment product from the main reservoir (1) through the flap-type or ball-type inlet valve (7), the product also entering under gravity feed which means that the pump is self-priming and self-filling.

There are three possible forms that the auxiliary reservoir (15) can adopt:

The form of auxiliary reservoir (15) that is open with filling slot, see FIGS. 1, 2 and 7.

The form of auxiliary reservoir (15a) that is closed and sealed, see FIG. 8.

The form of auxiliary reservoir (15b) that is open with an inlet valve, see FIG. 11.

In the form of auxiliary reservoir (15) that is open with filling slot and adjusting slide (21), FIGS. 2 and 7, as the toilet cistern (2) fills, the rising water level submerges the float (20) which, by acting on the lever (19), closes the discharge valve (17). Next, the rise in water level submerges the float (10) which rises and its upthrust on the piston (6a) ceases upon contact with the end-stop adjusting rod (5) that determines the set volume of the dose, materially embodied by the lowermost and uppermost positions of the piston (6a), FIGS. 2 and 5. The dose of product drawn into and contained in the metering pump (6) above the double-lip seal (9) is transferred to the auxiliary reservoir (15) passing through the outlet valve (8) then along the duct (8a) to be tipped by the pouring spout (8b) into the auxiliary reservoir (15).

On each toilet operating cycle, a dose of product is transferred and injected into this auxiliary reservoir (15), at the setting that has been set.

As the cistern (2) continues to fill and reaches its maximum level, the water fills the auxiliary reservoir (15) via the slot, passing over the slide (21), see detail in FIG. 7. The slide (21) has to be set a few millimeters lower down than the maximum water level in the toilet cistern in order to allow the water to fill the auxiliary reservoir (15) and mix with the product from the pouring spout (8b) in order to achieve the predilution. With this position of the slide (21), if there is some variation in the level in the toilet cistern, the content of the auxiliary reservoir (15) will not be affected by this nor will it be dispersed into the water of the toilet cistern.

As the toilet cistern (2) empties toward the end of the flush while, during the discharge, around 1.5 liters, namely a depth of 4.5 centimeters, of water still remain in the reservoir (2) ready to leave, the float (20) mounted on the articulated lever (19) tips and causes the valve (17) to open instantly, releasing the column of prediluted product contained in the auxiliary reservoir (15). The predilution of treatment product contained in the auxiliary reservoir (15) immediately mixes and is discharged with the end of the flush, the treatment product, the final volume of which corresponds to the volume of the U-bend, being calculated so that it is not discharged down the drain, coats all of the surfaces as it passes, and ends up flowing into the U-bend of the toilet bowl where it is collected and held so that it cleans, disinfects and deodorizes the toilet automatically, and the same operation is repeated each time the toilet is used.

In the form of auxiliary reservoir (15a) that is closed and sealed, as per FIG. 8, as the toilet cistern (2) fills, the rising water level submerges the float (20) which, by action on the lever (19), closes the discharge valve (17).

Next, the rise in water level submerges the float (10) which moves upward and its upthrust on the piston (6a) stops upon contact with the end-stop adjusting rod (5) which determines the set volume of the dose which is materially embodied by the lowermost and uppermost positions of the piston (6a), FIGS. 2 and 5.

The dose of product drawn into and contained in the metering pump (6) above the double-lip seal (9) is transferred to the auxiliary reservoir (15a), passing through the valve (8) and then along the duct (8a) to be tipped by the pouring spout (8b) into the auxiliary reservoir (15a).

On each toilet operating cycle, a dose of product is transferred and injected into this auxiliary reservoir (15a), according to the setting that has been set.

The ever-rising water level reaches the inlet valve (18), the sealed cover (16) keeps the air in this auxiliary reservoir (15a), and water enters via this valve up to its level, then stops entering the reservoir (15a) because of the vacuum bell effect. The amount of water admitted is determined by the position of the inlet valve (18).

The inlet valve (18) does, however, allow the reserve of air, due to the depth of water in the cistern (2) to pass through into this auxiliary reservoir (15a), and pressurize it, this reserve of air being compressed in the auxiliary reservoir (15a) above the predilution. The sealed connection between the duct (8a) and the flap-type or ball-type outlet valve (8) and the inlet valve (18) prevent any leaks or returns and the pressure and the predilution can be released only by the opening of the discharge valve (17), even if the water level in the toilet cistern (2) were to drop without reaching the level at which the opening of the discharge valve (17) is triggered. The pressure of the air inside the auxiliary reservoir (15a) is equalized with the external water pressure, making any leak via the valves (17) and (18) impossible if the toilet cistern has not emptied.

The volume of air in the auxiliary reservoir (15a) needs to be as voluminous as possible in order to obtain the best propulsion behind the discharge of the predilution.

When the toilet is used, once the water is in the process of discharging, at the precise moment just at the end of the flush cycle when the water level in the toilet cistern suddenly causes the float (20) to drop and just 1.5 liters of water remain in the toilet cistern at the end of the flush, the sudden drop of the float (20) mounted on the articulated lever (19) triggers the instant opening of the discharge valve (17). The reserve of compressed air contained inside the auxiliary reservoir (15a) instantly, upon the opening of the discharge valve (17), drives the predilution into the on-going discharge leaving the toilet cistern (2). At this precise moment there is no longer any external pressure and the end of the flush comprising around 1.5 liters of water with a dose of product constitutes a correctly dosed solution of sanitary product. This mixture of product covers and coats all of the interior surfaces of the water reservoir, the circulation ducts, reaches, coats and adheres to all of the interior surfaces of the toilet bowl and this quantity of treatment mixture, the final volume of which corresponds to the volume of the U-bend, is calculated so as not to be flushed down the drain, and ends up flowing into and being collected and held in the U-bend of the toilet bowl. The product will be able to act correctly over time on all the product-coated surfaces, and between each use of the toilet the product will have time to act in the same way as in a manual operation, to clean, disinfect and deodorize the entire interior of the toilet and use the minimum amount of product and of water for this final operation. Because it is present in the toilet bowl, the product also acts in the U-bend.

In the form of auxiliary reservoir (15b) that is open with an inlet valve, as in FIG. 11, in the same way as in the previous two forms, once the toilet has been used, the rising water level in the cistern (2) submerges the float (20) which, by acting on the lever (19), closes the discharge valve (17). Next, see FIG. 2, the rising water level submerges the float (10) which rises and pushes on the piston (6a), the vertical upthrust of the piston (6a) stops upon contact with the end-stop adjusting rod (5) used for setting the volume of the dose, materially embodied by the lowermost and uppermost positions of the piston in FIGS. 4 and 5. The dose of product drawn into and contained above the double-lip seal (9) of the metering pump (6) is transferred, passing through the outlet valve (8) and along the duct (8a) to be poured by the pouring spout (8b) into the auxiliary reservoir (15b). The filling of the cistern (2) continues and on reaching the inlet valve (18) the water enters and continues until it fills the auxiliary reservoir (15b) to the same level as the water level in the cistern (2), thus leading to a column of prediluted product. The pressures on the inside and on the outside of the auxiliary reservoir (15b) are the same and the valve (18) prevents any egress of liquid even if the level on the outside drops without reaching the float (20). If there is a variation in the water level in the toilet cistern, the content of the auxiliary reservoir (15b) will not be affected by this, nor will it be dispersed in the water of the toilet cistern. In this form of auxiliary reservoir (15b), the inlet valve (18) can be positioned between the lowest and highest water levels of the toilet cistern.

As the toilet cistern (2) empties, towards the end of the discharge when around 1.5 liters, namely a depth of 4.5 centimeters of water are yet to be discharged, the float (20) mounted on the articulated lever (19) tips and causes the instant opening of the discharge valve (17) which releases the predilution column of treatment product contained in the reservoir (15b). At this precise moment there is no longer any external pressure and water and the predilution immediately mixes and is discharged with the end of the flush and the treatment product, the final volume of which corresponds to the volume of the U-bend, is calculated so that it is not flushed down the drain, so that it coats all the surfaces as it passes, and ultimately flows into and is collected and held in the U-bend of the toilet bowl.

The filling cycle then starts over and water rises up inside the toilet cistern (2).

The adjustment-volume metering pump automatic dispenser in FIG. 1 is made up of the membrane pump (4c) version of metering pump and of the form of auxiliary reservoir (15) that has filling slot and slide (21) of FIGS. 3 and 7.

The way in which this version of adjustable-volume metering pump automatic dispenser with membrane pump (4c), FIGS. 1 and 3, works is the same as for the piston-pump (6) version, except that its design is less elaborate. The screwed or notched assembly of the metering pump (4) means that the membrane (4c), the seal (4b) and the upper part of the pump (4a) with the reservoir (1) can be clamped to its periphery. The plate (4e) fixes the membrane (4c) to the plunger (4d). The membrane (4c) needs to be flexible and inelastic.

As the toilet cistern (2) empties, the float (10) mounted on the plunger (4d) pulls in a downward direction the membrane (4c) which is fixed to the plunger (4d) by the plate (4e). The product in the reservoir (1) enters via the inlet valve (7) and fills the upper part of the membrane (4c), toward the end of the discharge when around 1.5 liters, namely a depth of 4.5 centimeters, of water still remain in the cistern (2) ready to be discharged. The float (20) tips and via the articulated lever (19) causes the instant opening of the discharge valve (17) which releases the column of predilution of treatment product contained in the auxiliary reservoir (15). At this precise moment there is no longer any external pressure and the predilution immediately mixes and is discharged with the end of the flush and this final volume of treatment product corresponds to the volume of the U-bend and is calculated so as not to be flushed down the drain but to coat and adhere to all the surfaces as it passes and the mixture ends up flowing into and being collected and held in the U-bend of the toilet bowl.

Once emptying is complete, the refilling of the toilet cistern (2) begins. The rise in water level submerges the float (20) which, by acting on the lever (19), closes the discharge valve (17), then the rising water level submerges the float (10) which rises, and its upthrust on the piston plunger (4d) and on the membrane (4c) stops upon contact with the end-stop adjusting rod (5) which determines the setting for the volume of the dose. The dose of product drawn into and contained in the metering pump (4) above the membrane (4c) is transferred to the auxiliary reservoir (15), passing via the valve (8), flows along the duct (8a) to be tipped via the pouring spout (8b) into the auxiliary reservoir (15).

The filling of the cistern (2) continues until the maximum level is reached, the water fills the auxiliary reservoir (15) via the slot passing over the slide (21), FIGS. 1 and 7. The slide (21) has to be set a few millimeters lower down than the maximum water level in the toilet cistern in order to allow the water to fill the reservoir (15) and mix with the product from the pouring spout (8b); if a variation in the water level in the toilet cistern occurs, the content of the auxiliary reservoir (15) is not affected by it, nor is it dispersed in the water of the toilet cistern.

The adjustable-volume metering pump automatic dispenser cycle is over, until the toilet is next used, and this cycle will recommence each time the toilet is used. The automatic cleaning and disinfection thus obtained of all the sensitive parts of the toilet make the upkeep task easier, quicker and less painstaking for those who have to do it and eliminate nuisance and unpleasantness.

The use of this adjustable-volume metering pump automatic dispenser is very useful for private use in toilets equipped with cistern-fed washroom facilities, although the use of the adjustable-volume metering pump automatic dispenser is recommended for private and public washrooms, washrooms in superstores, in a professional company environment, restaurants, hotels, holiday centers and is indispensable in the health sector in hospitals, clinics, social medical reception centers where a permanent hygiene solution and fight against bacteria is a constant and absolute key requirement.