EP0033684B1 - Dispenser for a liquid product and washing machine comprising such a dispenser - Google Patents

Description

The invention relates to the technique of dispensing liquid products; more precisely, it relates to a liquid product dispenser making it possible to dilute, in the filling water of a tank, a predetermined dose of a liquid additive; it also relates to a washing machine comprising such a dispenser.

In a washing machine, for example a washing machine, it is necessary, during the various stages of the programmed washing cycle, to add, to the filling water of the tank, different liquid additives such as products: detergents, fabric softeners, sanitizers, scented fabric softeners, etc.

Currently, domestic washing machines in service include at least one product container in which there is manually, before the start-up operation, a predetermined dose of an additive which must be diluted in the filling water of the tank. Recently, it has appeared on the market for washing machines, in particular, dish washing machines which comprise a dispenser comprising a reservoir for storing a reserve of a liquid additive, a metering container, and generally electromagnetic means, allowing to take a dose of product, to withdraw this dose, then to deposit it in the tank of the machine.

According to a different technique, the liquid product dispenser comprises: a reservoir for storing a reserve of a liquid additive placed in the lower part of the machine and a metering electric pump (peristaltic pump) controlled by the programmer of the machine, the size the dose of liquid additive released into the tank is determined by the duration of excitation of the electro-pump.

These liquid product dispensers have various drawbacks, in particular: the reserve of liquid product is in contact with the atmosphere from which this results in partial oxidation of the product thus stored; these dispensers do not include means ensuring the automatic and periodic rinsing of the constituent elements, and the means making it possible to withdraw a predetermined dose of the product, then to inject this dose into the water of the tank are relatively complex, with the consequence increased cost and reduced machine reliability.

Furthermore, in publication EP-A-0 020 252, a dispenser of doses of liquid product for a washing machine is already described, comprising a hermetically closed product tank, a metering chamber which is connected to this tank and disposed below the lower level of the latter, receives water which directly drives out the dose of product and at the same time rinses this dosing chamber. However, this dispenser has the drawback of being bulky.

In publication DE-B-2 239 484, the dispenser described comprises a product reservoir, a product supply chamber coming from this reservoir through a valve controlled by float and membrane sensitive to liquid pressure, and a chamber intermediate connected on one side to this chamber through metering valves and on the other side to a pipe for circulation of liquid. When the liquid circulates in this pipe, a vacuum is created in this intermediate chamber, and the product located above the level of the opening of the metering valves and the intermediate chamber is entrained by this current of liquid. When this flow of liquid is stopped, the liquid pressure reestablishes in the intermediate chamber, closes the metering valves and opens the valve of the product reservoir to fill the supply chamber. This distributor has a more or less complicated and expensive structure and the drawback of having a reservoir and a supply chamber which can only function properly if they are vented. In addition, no rinsing of the metering valves and of these supply and intermediate chambers is carried out automatically.

In publication FR-A-2 410 697, the product dispenser comprises a water pump to which are connected in parallel, the machine tank and the container or containers containing different products.

This dispenser has the disadvantage of having containers for products which bring these products into contact with air and does not rinse the pipes bringing the products.

The object of the present invention is to avoid these drawbacks.

According to the invention a liquid product dispenser having an airtight storage tank placing a reserve of liquid product or additive away from the atmosphere, a metering container disposed below the lower level of this tank, is characterized in that 'it comprises on the one hand in the hermetic tank, an internal pressure balancing means constituted by a tube having an upper end open in the space above the maximum level of this reserve of product and a lower part in communication with a pipe connecting a vacuum outlet of an injection means and the metering container through a withdrawal means provided with a hydrostatic valve, and on the other hand through a hydrostatic valve a communication between the lower part of the tank airtight and an inlet, at the bottom of the dosing container.

According to another characteristic of the invention, a cavity for retaining a small quantity of running water is arranged at the outlet of a venturi of the injection means with vacuum connection.

According to another characteristic of the invention, the means for balancing the internal pressure of the storage tank is provided with a hydrostatic valve located near the lower level of this tank.

According to another characteristic of the invention, the means for withdrawing the dose of liquid product comprises means making it possible to vary the position of the withdrawal orifice, in order to modify the magnitude of the dose of product injected into the tank filling water.

The liquid product dispenser has elements static elements such as hydrostatic valves which can be flushed periodically by retaining water stored in the cavity located downstream of the venturi.

• la figure 1 représente, sous une forme schématique, la structure de base, selon l'invention, d'un distributeur de produit liquide,
• la figure 2 représente, sous une forme schématique, le distributeur de produit liquide de la figure 1, dans lequel le récipient doseur est intégré au réservoir de stockage du produit liquide,
• la figure 3 représente, sous une forme schématique, le distributeur du produit liquide de la figure 2, comprenant un moyen permettant de modifier la grandeur de la dose de produit liquide injectée dans l'eau de remplissage de la cuve,
• la figure 4 représente, selon une vue en coupe, les détails de réalisation du distributeur de produit liquide de la figure 3.

Other characteristics and advantages will appear in the description which follows, of a liquid product dispenser, made with reference to the appended drawings; on these drawings:

• FIG. 1 represents, in schematic form, the basic structure, according to the invention, of a liquid product dispenser,
• FIG. 2 represents, in a schematic form, the liquid product dispenser of FIG. 1, in which the dosing container is integrated into the storage tank for the liquid product,
• FIG. 3 represents, in a schematic form, the dispenser of the liquid product of FIG. 2, comprising a means making it possible to modify the magnitude of the dose of liquid product injected into the filling water of the tank,
• 4 shows, in a sectional view, the details of the embodiment of the liquid product dispenser of FIG. 3.

• - un réservoir 1 permettant de stocker une réserve du produit liquide; ce réservoir est muni d'un orifice de remplissage 2 du produit, qui est clos par une fermeture hermétique 3; ce réservoir incluant un moyen d'équilibrage de la pression interne comprenant, par exemple, un tube 4 dont l'orifice supérieur 5 débouche au-dessus du niveau maximal H du liquide; ce tube étant muni, éventuellement, à son extrémité inférieure 6, d'une valve hydrostatique 7 située à proximité du fond de ce réservoir,
• - un récipient doseur 8 dont le volume interne est sensiblement égal à la dose maximale du produit qui doit être prélevée dans le réservoir 1; ce récipient doseur situé en dessous du niveau inférieur du réservoir comporte: un moyen de prélèvement du produit liquide comprenant: un orifice d'admission 9 situé à la partie inférieure du récipient et une liaison 10 dans laquelle est insérée une valve hydrostatique 11; un moyen d'aération comprenant: une entrée d'aération 12 située à la partie supérieure de ce récipient doseur, cette entrée d'aération étant munie d'un tube d'aération 13 dont l'orifice supérieur 14 débouche à l'air libre au-desses du niveau maximal H du produit liquide, et, un moyen de soutirage de la dose comprenant un tube 15 dont l'extrémité inférieure, ou orifice de soutirage 16 débouche à l'intérieur du récipient et la partie supérieure, ou orifice d'évacuation 17, est reliée, d'une part, au moyen d'aération du réservoir 1 par un conduit 18 et, d'autre part, au moyen d'injection du distributeur par une canalisation 19; de plus, une valve hydrostatique 20 est disposée entre ces orifices de soutirage et d'évacuation,
• - un moyen d'injection de la dose de produit liquide constitué par un venturi, ou trompe à eau, 21; l'entrée 21 a de cette trompe étant reliée à une source A, d'alimentation en eau courante, par une électrovanne 22 commandée par un signal électrique CMD fourni, par exemple, par le programmateur de la machine; la prise de dépression 21 b de cette pompe est relié à l'orifice d'évacuation 17 du moyen de soutirage et la sortie 21 c est reliée, à travers une cavité 23 de retenue d'une faible quantité d'eau, à une canalisation 24 terminée par une embouchure 25 débouchant dans la cuve C non représentée sur cette figure.

Figure 1 shows, in schematic form, a liquid product dispenser for taking from a tank, a predetermined dose of a liquid additive and injecting this dose into the filling water of the tank of a machine to wash. According to the invention, this dispenser comprises:

• - A tank 1 for storing a reserve of the liquid product; this reservoir is provided with a filling orifice 2 for the product, which is closed by a hermetic closure 3; this reservoir including a means for balancing the internal pressure comprising, for example, a tube 4, the upper orifice 5 of which opens out above the maximum level H of the liquid; this tube being optionally provided, at its lower end 6, with a hydrostatic valve 7 located near the bottom of this tank,
• - A metering container 8 whose internal volume is substantially equal to the maximum dose of the product which must be taken from the tank 1; this metering container located below the lower level of the reservoir comprises: a means for withdrawing the liquid product comprising: an inlet orifice 9 located at the bottom of the container and a connection 10 into which a hydrostatic valve 11 is inserted; aeration means comprising: an aeration inlet 12 located at the upper part of this metering container, this aeration inlet being provided with an aeration tube 13, the upper orifice 14 of which opens into the open air below the maximum level H of the liquid product, and, a means for withdrawing the dose comprising a tube 15 whose lower end, or withdrawal orifice 16 opens into the container and the upper part, or orifice d evacuation 17 is connected, on the one hand, by means of aeration of the reservoir 1 by a conduit 18 and, on the other hand, by means of injection of the distributor by a pipe 19; in addition, a hydrostatic valve 20 is disposed between these withdrawal and evacuation orifices,
• a means for injecting the dose of liquid product constituted by a venturi, or water pump, 21; the inlet 21 a of this trunk being connected to a source A, for supplying running water, by a solenoid valve 22 controlled by an electrical signal CMD supplied, for example, by the programmer of the machine; the vacuum outlet 21 b of this pump is connected to the discharge orifice 17 of the withdrawal means and the outlet 21 c is connected, through a cavity 23 for retaining a small amount of water, to a pipe 24 terminated by a mouth 25 opening into the tank C not shown in this figure.

A hydrostatic valve can be constituted, for example, by a spherical ball resting on a conical seat, this ball possibly being held captive by an openwork wall.

The hydrostatic valve 7, located at the lower part of the storage tank 1 comprises a ball whose apparent density is notably lower than the density of the liquid product stored in the tank; the function of this valve is to isolate the tube 4 from the reservoir when the level of the liquid product reserve is above the level of the ball.

The hydrostatic valve 11, located at the filling orifice 9 of the metering container 8 comprises a ball whose apparent density is substantially greater than the density of the liquid product, this ball has a weight of value M 1; it rests on its conical seat whose cross section of contact has a value S 1; the function of this valve is to isolate the storage tank 1 from the metering container 8 when the venturi creates a depression in the tube 19; conversely, when the solenoid valve 22 is cut, this valve 11 must allow the transfer of a dose of product from the storage tank to the metering container. To do this, the following condition must be satisfied: the weight M1 of the ball must be less than the thrust S1 P1 created by the liquid reserve contained in the storage tank where P1 is the pressure resulting from the difference in product levels in the tank and in the dosing container.

The hydrostatic valve 20 located in the tube 15 includes a ball whose apparent density is significantly greater than the density of the liquid product; this ball has a weight of value M2 and it rests on its conical seat whose cross section of contact has a value S2; the function of this valve is to isolate the metering container 8 from the tube 17 when the vacuum in this tube is zero; to do this, the following condition must be satisfied: the weight M2 of the ball must be greater than the thrust S2P2 exerted by the liquid product, where P2 is the pressure resulting from the difference in the levels of the liquid reserve and the valve .

We will now describe the operation of the liquid product dispenser shown in Figure 1. We will first consider a simplified dispenser in which the water retaining cavity 23 and the hydrostatic valve 7 have been eliminated, and where the end 6 of tube 4 was closed. When the solenoid valve 22 is not energized, the pressure prevailing in the tube 19 is the ambient atmospheric pressure Po, the ball of the valve 20 is applied to its seat and the hydrostatic pressure P1 on the ball of the valve 11 allows total filling. of the metering container 8 and partial of the aeration tube 13 whose internal volume is negligible compared to the internal volume of the metering container.

When the solenoid valve 22 is energized, the water passing through the venturi creates a strong vacuum in the tube 19 and, correspondingly, above the liquid product in the storage tank, the ball of the valve 11 is, consequently , strongly applied to its seat and isolates the storage tank; conversely, the ball of the valve 20 is lifted from its seat, and the dose of product is sucked in by the venturi then transferred into the line 24 for filling the tank of the machine.

We will now consider the addition of the water retaining cavity 23; when the excitation of the solenoid valve 22 is cut off, the small quantity of retained water flows through the tube 19 and rinses the corresponding pipes.

We will now consider the addition of the hydrostatic valve 11; when the storage tank 1 is completely empty, the retaining water from the cavity 23 flows through this valve into the tank and, provided that the user of the machine does not replenish the tank with product, in the following cycle , the venturi will suck up this rinse water.

FIG. 2 represents, in schematic form, a variant of the structure of the liquid product dispenser described in FIG. 1. According to this variant, the metering container 8 is integrated inside the reservoir 1 for storing the reserve of the liquid product.

In this FIG. 2, the dispenser is partially shown and identical references designate corresponding elements identical to those of FIG. 1.

• - à sa base, une protubérance 1 a à l'intérieur de laquelle est disposé le récipient doseur muni de ses moyens de prélèvement, d'aération, et de soutirage, la liaison 10 étant constituée par l'espace libre entre les parois de la protubérance 1 a et les parois du récipient doseur 8,
• - à sa partie supérieure, une ouverture 30 close par une fermeture hermétique 31 traversée: d'une part, par le tube d'aération 13 et, d'autre part, par le tube d'évacuation 19; les dimensions de l'ouverture 30 étant supérieures aux dimensions du récipient doseur 8.

According to this structural variant, the reservoir 1 comprises:

• at its base, a protuberance 1 a inside of which is placed the metering container provided with its means for sampling, aeration and withdrawal, the connection 10 being constituted by the free space between the walls of the protrusion 1 a and the walls of the metering container 8,
• - At its upper part, an opening 30 closed by a hermetic closure 31 crossed: on the one hand, by the ventilation tube 13 and, on the other hand, by the evacuation tube 19; the dimensions of the opening 30 being greater than the dimensions of the metering container 8.

The operation of this variant structure of the dispenser is identical to the operation of the dispenser as described above.

FIG. 3 represents, in diagrammatic form, the liquid product dispenser of FIG. 2 in which the level of the withdrawal orifice 16, relative to the bottom of the dosing container 8, can be adjusted in order to vary the size of the dose of product aspirated by the venturi. In this FIG. 3, the dispenser is partially shown and identical references designate corresponding elements identical to those of the preceding figures. The means for withdrawing from the metering container comprises a tube 32 fixed to the upper wall of the metering container, this tube passing through the hermetic closure 31 and comprising a first orifice for communication with the conduit 18 and a second orifice for communication with the pipe 19. A the lower end of this tube 32 is arranged a hollow sliding piston provided with the withdrawal tube 15 and the hydrostatic valve 20. A rigid rod 34 can slide in a hermetic closure 35 and is fixed to the piston 20 by an openwork mechanical connection; this rod possibly carries graduations 36 in order to visually indicate the magnitude of the dose of product which will be sucked in by the venturi at each operating cycle.

Figure 4 shows, in a sectional view, the details of embodiment of the liquid product dispenser described in Figure 3. The storage tank 1 can be made of a plastic material according to an extrusion process, for example: its shapes exterior are mainly dictated by its location in the washing machine considered. The metering container can be manufactured in two elements: a first element which constitutes the container itself and a second element, or cover, which comprises: the tube 32, the ventilation opening 12 and, optionally, the seat and the ball hydrostatic valve 7.

The hollow piston 33 is provided with a seal 33a, and with a pin 33b which passes through the adjustment rod 34.

In the embodiment shown, the adjustment rod 34 is folded towards an external wall of the storage tank and it carries an index 34a which can be read opposite the marks inscribed on this external wall. The internal volume of the dosing container is, for example, of the order of a tenth of a liter, and that of a dose which is sometimes lower, which, for a capacity of the storage tank of a liter or more, ensures washing autonomy. important between each product supply. The ball of the hydrostatic valves can be made of a material such as a plastic material, a resin or a metal, according to the apparent density required.

A liquid product dispenser according to the invention can equip an automatic washing machine. The storage tank, the metering container and its pipes can be arranged in the lower part of the machine, advantageously, in the vicinity of the front of this machine; this facade is then equipped with an access door to the filling orifice of the storage tank and to the rod for adjusting the dose of product to be diluted in the filling water of the tank. The other accessories such as the solenoid valve and the venturi can be arranged in various locations of the machine.

• - la réserve de produit est isolée de l'atmosphère ambiante par la retenue d'eau qui se déverse dans le tube 19,
• - la grandeur de la dose de produit prélevée dans le récipient doseur est indépendante de la viscosité du produit,
• - les tubulures sont rincées cycliquement et automatiquement,
• - l'absence de mécanismes complexes confère au distributeur une fiabilité intrinsèque élevée.

We now see more clearly, apart from the autonomy conferred on the machine, the advantages which a liquid product dispenser according to the invention provides:

• - the product reserve is isolated from the ambient atmosphere by the water retention which pours into the tube 19,
• - the size of the dose of product taken from the dosing container is independent of the viscosity of the product,
• - the pipes are rinsed cyclically and automatically,
• - the absence of complex mechanisms gives the distributor high intrinsic reliability.

Such a liquid product distributor finds its application in domestic washing machines or not.

Claims (8)

1. A dispenser of liquid products having a hermetic stocking container (1) which shelters a stock of the liquid product or additive from the atmosphere, and a dosing receptacle (8) which is located underneath the lower level of this container, characterized in that it comprises on the one hand in the hermetic container (1) a means for balancing the inner pressure, this means being constituted by a tube (4) having an upper end which opens into the space above the uppermost level of this stock of product, and a lower end which communicates with a pipe (19) connecting a tap of low pressure (21 b) of an injection means (21-21a) with the dosing receptacle (8) via a suction means (15), this means being provided with a hydrostatic valve (20), and on the other hand a communication via a hydrostatic valve (11) between the lower part of the hermetic container (1) and an inlet opening (9) located at the lower part of the dosing receptacle (8).

2. A dispenser according to claim 1, characterized in that it comprises close to the base of the stocking container (1) a hydrostatic valve (7) mounted at the lower end of the tube (4) which constitutes the means for balancing the inner pressure of said container.

3. A dispenser according to one of the claims 1 and 2, characterized in that it comprises in the lower part of the stocking container for the stock of liquid product (1) a hollow protuberance (1 a) which opens to the inside and in which a dosing receptacle (8) is located.

4. A dispenser according to claim 1, delivering adjustable doses of the product, characterized in that it comprises in the suction means (15) for the product which is contained in the dosing receptacle (8), a means able to modify the level of the opening of this suction means (15) with respect to the bottom of said dosing receptacle (8).

5. A dispenser according to claim 4, characterized in that means which are able to modify the level of the opening of the suction means (15) with respect to the bottom of the dosing receptacle (8) comprise a hermetically closed tube (32) which is fixed to the upper wall of the dosing receptacle (8) and comprises a sliding piston and a sliding shaft (34) which bears an indication graduation for the amount of product to be dispensed, this sliding shaft ensuring the positioning of the piston, the tube (32) being connected on the one hand to a tap of low pressure (21 b) of the venturi (21) belonging to the injection means and on the other hand to the pressure balancing means (4) of the stocking container.

6. Washing machine equipped in particular with a programming device for the washing cycle connected to a feed water electrovalve, characterized in that it comprises a dispenser of liquid products according to one of the claims 1 to 5.

7. A washing machine according to claim 6, characterized in that the stocking container and the dosing receptacle are disposed in the lower part of this machine.

8. A washing machine according to claim 7, characterized in that it comprises an access gate which is located in front of the stocking container and of the adjusting shaft of the sliding tight piston.

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