ITTO20120640A1 - DOMESTIC DISHWASHER MACHINE - Google Patents

Description

DESCRIPTION of the industrial invention entitled:

â € œHousehold dishwasher machineâ €

TEXT OF THE DESCRIPTION

Field of invention

The present invention relates to a domestic dishwashing machine and to a related method for treating dishes.

Prior art

Modern dishwashers include a washing tank, inside which at least two crockery racks in superimposed positions and at least two sprayers, which are usually located one below the lower basket and the € ™ other under the upper basket. Limited load dishwashers usually comprise a single dish rack and a single sprinkler member.

In the normal operation of a dishwasher, the water is loaded from the mains into the washing tank, so as to collect on its bottom. The bottom of the tank typically includes a collecting sump, usually provided with a water filtering system. A washing pump takes the water collected in the well and sends it to the sprinklers. The water comes out of the sprinkler nozzles and hits the dishes contained in the relative baskets with relative force, for the purpose of their treatment. In order to carry out some dish treatment phases, for example a washing phase or a hot rinse phase, the water must be heated to a certain temperature established by the operating program, approximately between 45 and 75 ° C according to the various phases. The heating is carried out by means of one or more electric resistances. Some operating programs also include cold treatment phases, typically represented by a first rinse.

Modern dishwashers are increasingly conceived to guarantee a high quality of the treatment process and an efficient use of energy and water resources and for this purpose some dishwashers are equipped with auxiliary functional systems. A typical auxiliary system used on some machines is represented by a forced ventilation or drying system for dishes, which generally includes a condensation device outside the tank, attached to one of its stationary walls, or positioned inside the door of the tank. machine. In these machines, the overall quality of the treatment is increased because, at the end of a machine operating cycle, the dishes are almost completely dry and ready for a new use or to be put away. Another example of an auxiliary system is represented by a liquid accumulation system, based on the use of a container external to the tank and set against one of its stationary walls. In some machines the storage tank is envisaged with the aim of obtaining, in the context of at least one hot phase of a treatment cycle, a partial heating of the water to be used in a subsequent phase of the same cycle, exploiting the heat exchange that takes place between a wall of the tank and the tank attached to it.

The realization of dishwashing machines equipped with auxiliary systems of the indicated type is generally complex, particularly when the machine must be equipped with both of the above-mentioned systems.

Purpose and summary of the invention

In view of the foregoing, the present invention proposes to provide a dishwashing machine, of the type including a liquid accumulation system and a drying system, of simple and economical construction, reliable operation and increased efficiency.

This object is achieved, according to the present invention, by a dishwashing machine having the characteristics of claim 1. Preferred characteristics of the invention are indicated in the sub-claims. The claims form an integral part of the technical teaching provided in relation to the invention.

Brief description of the drawings

Further objects, characteristics and advantages of the present invention will become clear from the following description, made with reference to the attached drawings, provided purely by way of non-limiting example, in which:

- figure 1 is a schematic perspective view of some components of the supporting structure of a dishwashing machine according to the invention;

- figure 2 is a schematic section of a possible implementation of a collecting sump of a machine according to the invention, with a relative filter system;

- figure 3 is a simplified diagram of a possible hydraulic circuit of a machine according to the invention;

Figure 4 is a schematic perspective view of a first valve device used in a machine according to a possible implementation of the invention;

Figure 5 is a schematic perspective view of a second valve device used in a machine according to a possible implementation of the invention;

- figure 6 is a schematic plan view of a possible arrangement of components inside a base of a machine according to the invention;

- figure 7 is a schematic perspective view of a possible embodiment of a heat exchanger of a machine according to the invention;

- figure 8 is a schematic section, according to a vertical plane, of the exchanger of figure 7;

- figures 9 and 10 are perspective views of two different hollow modular elements forming part of the exchanger of figure 7;

- figure 11 is a side elevation view of the modular element of figure 9;

- figure 12 is a schematic plan view of the exchanger of figure 7, with an upper part removed;

- figure 13 is a partial and schematic section, according to a horizontal plane, of the exchanger of figure 7;

- figure 14 is a schematic section in lateral elevation of the exchanger of figure 7;

- Figures 15 and 16 are simplified diagrams similar to that of Figure 3, relating to possible variants of the invention.

Description of preferred embodiments of the invention

The reference to "an embodiment" within this description indicates that a particular configuration, structure, or feature described in relation to the embodiment is included in at least one embodiment.

Thus, the terms â € œin one embodimentâ € and the like, present in different parts within this description, are not necessarily all referring to the same embodiment. Furthermore, the particular configurations, structures or features can be combined in any suitable way in one or more embodiments. The references used below are for convenience only and do not define the scope of protection or the scope of the forms of implementation.

It should also be noted that in the following of the present description only the elements useful for understanding the invention will be described, assuming that the machine according to the invention includes all the elements known per se for the operation of a dishwasher, including its possible external cabinet, a user interface, a control system, level sensor means, a water heating resistance, a dispenser of washing agents, and so on.

Figure 1 schematically shows a dishwashing machine for domestic use according to a possible embodiment of the present invention. The machine 1 is illustrated limitedly to the parts of immediate interest for the understanding of the present invention.

The machine 1 has a structure which comprises a base 2 and a washing tank 3 supported by the base 2. The base 2, made for example of injection-molded thermoplastic material, has preferably open side walls and defines a housing space 2a, within which various functional components of the machine 1 are positioned, including a washing pump, a drain pump, part of the water collection well, a descaling device (if provided), these elements not being shown in the figure for needs for greater clarity of the drawing. The washing tank 3, of a generally known concept, comprises an upper wall 3a, a lower wall 3b and four side walls. In the figures, only the stationary side walls of the tank 3 are visible, ie the rear wall 3c, and the right and left walls, indicated with 3d and 3e; the fourth side wall of the tank 3, that is its front wall, is made up of an internal shell of the machine door, not shown here (the so-called â € œ counter doorâ €).

It should be noted that the term `` base '' is intended to designate any structure capable of supporting at least the lower wall 3b of the tank from the ground, determining the presence of a housing space 2a: in this perspective, therefore, the base 2 could simply include a plurality of legs or upright elements which support the lower wall 3b from below.

The machine 1 preferably has dimensions in the order of the machines for domestic use currently on the market, and therefore with a width and depth between 55 and 60 cm and with a height between 80 and 85 cm.

From figure 1 it is visible how the lower wall 3b of the tank defines a central opening 3b ', in correspondence with which the aforementioned collection sump is mounted, integrating a water filtering system. This well, with an example of a possible filtering system (for example of the type known from FR-A-2503557), is represented schematically in figure 2.

In this figure, the lower wall 3b of the tank is visible, to which the sump is tightly fixed (in correspondence with the opening 3bâ € ™ in figure 1), indicated as a whole with 5. In the lower part of the sump there is find an exhaust outlet 5a, for connection to the intake branch of a drain pump, not shown; a second outlet 5b is defined in the side wall of the well 5, for connection to the suction branch of a washing or recirculation pump, also not shown.

Well 5 is covered at the top by a first fine filter 6, generally funnel-shaped and relatively wide in its upper part. This filter 6 continues downwards, inside the well 5, with a generally sleeve part 6a. In the example shown, this sleeve part 6a substantially extends up to the inlet of the outlet 5a for the drain pump. The sleeve part 6a of the filter 6 is surrounded by a tubular filter 7 with very thin meshes, and in any case narrower than those of the filter 6, of the type known as â € œmicro-filterâ €. As can be seen, the micro-filter 7 extends from the bottom towards the other, that is from the upper part of the filter 6 to the vicinity of the outlet 5a, thereby forming a cylindrical filtering surface which encloses the sleeve part 6a of the filter 6. In the case illustrated by way of example, finally, in the sleeve part 6a of the filter 6 a large mesh filter, indicated with 8, in the shape of a cup and equipped with of a handle 8a.

When only the washing pump is running, for example during a washing phase in the strict sense, the water is sucked towards the outlet 5b, in the direction indicated by the arrows in figure 2. Part of this water it follows the path outlined by the arrows DW, ie through the fine filter 6, which retains the coarse and fine dirt parts present in the water. These dirt parts are then transferred to the sleeve part 6a of the filter 6: the smallest parts of dirt are deposited at the outlet 5a, while the larger parts of dirt that could cause the drain pump to block ( think of a small bone), are retained by the large mesh filter 8. Another part of the washing water goes towards the central area of the filter 6, according to the path outlined by the arrows WW, and passes through the filter at large mesh 8, the sleeve part 6a of the filter 6 and the microfilter 7: in this way, therefore, the most voluminous particles of dirt are retained by the large mesh filter 8, by the sleeve part 6a the small particles of dirt and by the micro filter 7 the very small particles of dirt. The result of this filtering action, carried out through a plurality of filters with different meshes, allows to direct towards the washing pump, and therefore towards the dishes being treated, a basically clean water, or in any case from which it is most of the dirt particles have been removed.

On the other hand, when the washing water has to be drained from the tank, only the drain pump is activated, with the entire volume of water being sucked towards outlet 5a. Part of the water sucked towards the outlet 5a detaches the very small dirt particles that may have remained on the inside of the cylindrical wall of the micro-filter 7 and the small particles of dirt left on the internal side of the sleeve part 6a . Another part of the sucked water removes the fine dirt particles retained on the upper part of the filter 6, through the bottom of the large mesh filter 8, which in any case retains the larger parts of dirt. As mentioned, the filter 8 is removable and can therefore be periodically removed for cleaning.

Machine 1 is equipped with a drying circuit. In the example shown, the drying circuit is of the substantially closed type, and includes a hollow body, indicated as a whole with 10, with a vertical portion 10a which is generally parallel to the side wall 3d of the tank and an upper horizontal portion 10b generally parallel to the upper wall 3a of the tank. The portion 10b defines an inlet for the air which is coupled, for example with the interposition of a fan, to an opening in the upper wall 3a, while the portion 10a is in fluid communication with the interior of the tank 3, by means of a container described below. The drying circuit preferably includes at least one fan, as in the case shown (reference 50), operative to forcibly suck in humid air from the inside of the tank 3, through the aforementioned opening present in the upper wall 3a. The illustrated configuration of the hollow body 10, although preferred. it has an exemplary purpose only, the same being able to have a shape different from the one shown (for example including only the portion 10a, provided in one of its upper areas with an inlet communicating with the inside of the tank 3).

Figure 3 shows a simplified diagram of the hydraulic circuit of the machine 1, limited to the components useful for understanding the invention. In the exemplified case, at least a lower basket 11 and an upper basket 12 are provided throughout the tank 3, intended to contain respective loads of crockery. The baskets 11 and 12 are mounted - in a per se known manner - to be able to be extracted and / or removed through a front opening of the tank 3. The invention can however also be applied to machines equipped with a single basket, or even to machines equipped with more than two baskets. The structure of the machine includes a front door, not shown, the internal part of which forms a closing wall for the front opening of the tank 3.

The machine 1 has loading means, for loading water into the tank 3 from a domestic water network R. In the illustrated non-limiting example, these means include a first duct 13 for feeding water into the tank 3, the inlet of which It is connected to a fitting 14 for connection to the water mains R. Along the first duct 13 there are an air-break device and a decalcifying device, of known design and indicated respectively with 15 and 16. Between the fitting 14 and the blowing device 15, valve means 17 are provided on the duct 13, such as an electrovalve, controlled by a control system of the machine, not shown. Such a solenoid valve is not necessarily installed inside the machine 1, as it may belong to a well-known anti-flooding safety device (generally known as â € œacquastopâ €) to be installed upstream of fitting 14.

The loading means are configured to load a substantially predetermined quantity of water into the tank 3, which quantity can vary according to the type of treatment program and / or according to the operating step of a treatment program. For this purpose, the loading means preferably include metering means of a per se known type, not shown, such as a level sensor, such as a two-level pressure switch, or an impeller volumetric meter. The functions of the dosing means can also be performed, according to a known technique, by analyzing electrical quantities linked to the operation of a washing pump.

The machine 1 has a sprinkler system, which includes at least a first sprinkler member 18, for sprinkling the dishes contained in a relative basket with water, here the basket 11. In the case shown, since the machine has two baskets, the sprinkler system also includes a second sprinkler member 19, to sprinkle the dishes contained in the basket 12 with water. The invention is in any case also applicable to machines equipped with a single sprinkler member, or even to machines provided with more than two sprinkler members. Preferably, the sprinkler members 18 and 19 are rotary sprinklers, of a per se known conception. In the example shown, the hydraulic circuit of the machine includes two ducts, indicated with 20 and 21, to supply the sprayer 18 and the sprayer 19, respectively.

The number 22 indicates a washing or recirculation pump, i.e. a pump driven by an electric motor, for example a centrifugal pump, having a suction section, in fluid communication with the outlet 5b of well 5 (figure 2) and a delivery section, which is in fluid communication with the inlets of the ducts 20 and 21. In the embodiment of Figure 3, between the delivery section of the pump 22 and the inlets of the ducts 20 and 21 are operationally interposed means valve means 23, which are controlled by the control system of the machine 1, can be switched at least between a first condition, in which the delivery section of the pump 22 is in fluid communication with the sprinklers 18 and 19, through the relative ducts 20 and 21, and a second condition, in which the delivery section of the pump 22 is in fluid communication with only one of the sprinklers, for example the sprinkler 18, through the duct 20.

The valve means 23 can comprise two solenoid valves, each at the inlet of the respective duct 20 and 21, or operating along the respective duct 20 and 21. In a preferred embodiment, the valve means 23 consist of a device for alternating power supply of the sprinklers. Devices of this type are generally known (see for example DE-A-3904359 or DE-A-10000772) and normally provided on some dishwashers in order to allow the execution of treatment programs on the contents of only one of a couple of baskets, for example in the event of a reduced load of dishes, or for the execution of treatment programs with alternating power supply of a pair of sprinklers, all according to a known technique.

In the following, and unless otherwise specified, it is assumed that the means 23 consist of an aforementioned device for alternating power supply, having an internal shutter or distributor capable of assuming at least a first position, opening both ducts 20 and 21, and a second position, for opening the duct 20 and closing the duct 21; the distributor member may possibly also be able to assume a third position, opening the duct 21 and closing the duct 20.

Still in figure 3 the well 5 is visible, having the outlet 5b in fluid communication with the suction section of the pump 22. As mentioned, the well 5 is of a generally known conception, as well as the relative system of filtering (see figure 2). The lower outlet 5a of well 5 is connected to the suction branch of a drain pump 24, whose delivery branch is connected to a discharge pipe 25.

In the practical embodiment of the machine 1, the well 5 protrudes inside the base 2, or in the housing space 2a, in which the pumps 22, 24, the valve means 23 and the descaling device 16 (if provided) are also positioned . The jump device 15 in the air, on the other hand, can be placed against one of the side walls of the tank 3, as in use.

As per known technique, in order to carry out a dish treatment step, such as a washing step or a rinse step, the water loaded into the tank 3 reaches the bottom 3b and flows towards the well 5. The water is sucked from the well 5 by the pump 22, which forces the water into the ducts 20 and / or 21, to feed the sprinklers 18 and / or 19. The water coming out of the sprinklers 18 and / or 19 invests the dishes contained in baskets 11 and / or 12, and falls on the bottom 3b, to then return to well 5 and - after filtering - be re-introduced into circulation by the pump 22. At the end of the treatment step, the water present in the well 5 and / or on the bottom 3b of the tank is evacuated from the machine 1, by means of the drain pump 24 and the relative conduit 25, connected to a sewer network.

The machine 1 further comprises heating means, for heating the water loaded into the tank. These means too can be of any known type. The heating means preferably include at least one electrical resistance, whose electrical supply is controlled by the control system of the machine 1. The resistance can be integrated, for example, in the pump 22, for example in correspondence with its delivery section; in addition or alternatively, an electric resistance can be housed in the well 5, or mounted adjacent to the bottom of the tank 3b or in the suction branch of the pump 22, in a position such as to be immersed in the water during or at the end of a step for loading water into the tank, all according to a known technique.

The heating system can also include sensor means for detecting the temperature of the water, in signal communication with the control system of the machine, of any type known in the sector. The water heating can also be programmed by time, i.e. with the resistance being activated for a predetermined time (in this case, the temperature sensor means could possibly be omitted, if not required for regulatory and / or safety reasons. ).

The control system of the machine, not shown, is preferably of the type employing an electronic microprocessor, which comprises or with which memory means are operationally associated. As per the known technique, the control system is configured to supervise the general operation of the machine 1, and therefore the execution of the treatment program or programs that can be executed by the machine itself. Preferably, the memory means of the control system contain the data necessary for the execution of a plurality of possible treatment programs and the system includes control means, such as a control panel or user interface, provided with means for selecting a program among those available and start its execution.

One or more treatment programs that can be carried out by the machine generally comprise several operating phases that are performed with water, for example one or more washing phases and one or more rinsing phases. One or more of these steps performed with water may in turn include a loading step, at least a heating step, at least a treatment step and a discharge step. However, it should be noted that there are also possible phases in which water already present in the tank is reused or in which the water is not heated.

In general, in a loading step, a substantially predetermined quantity of water is loaded into the tank 3. Depending on the selection and start of a treatment program operated by the aforementioned control means, the control system commands the opening of the solenoid valve 17, for the purpose of introducing water from the mains into the tank water R. On reaching a certain volume or level of loaded water, the system closes the solenoid valve 17. In the heating step, the water loaded into the tank 3 is heated to a substantially predetermined temperature (if the phase in question It is a hot phase). To this end, the system enables the electric power supply of the aforementioned resistance. The electric power supply of the resistance is interrupted by the control system when the system itself detects, for example by means of relative temperature sensor means, that the temperature substantially predetermined by the program has been reached, or when a predetermined time has elapsed, in the case of heating at time. In the treatment step, the control system commands the pump 22 at a certain treatment speed, necessary to feed the water (heated or not), from the bottom of the tank 3b and from the well 5 to the sprinkler system 18 and / or 19 , so as to make the operation of this system effective for the purpose of treating the dishes. In essence, therefore, the motor of the pump 22 is operated at a speed capable of imparting a pressure to the water in the ducts 20 and 21 such that the water flows out of the holes of the sprinklers 18 and / or 19 with sufficient energy to strike the dishes contained in the respective baskets 11 and / or 12 and perform the washing or rinsing function; at the same time the water passes through each sprinkler with sufficient pressure to cause it to rotate, so that these dishes are cyclically hit by the water jets. At the end of the treatment step, or of the last planned treatment step, the drain step is performed, through which the water previously used for the treatment of the dishes is discharged from tank 3, by means of the drain pump 24 (or, according to a preferred embodiment of the invention, by means of the washing pump 22) controlled by the control system.

As mentioned, the control system of the machine 1 is designed to control the execution of a plurality of dish treatment programs. In one embodiment, such programs comprise at least one including treatment program

- a first operational phase using heated water, such as a washing phase,

- a second operating phase using preferably, but not necessarily, heated water, such as a first rinsing phase,

- a third operational phase using heated water, such as a second rinsing phase.

The space 2a houses a container for the accumulation of water, indicated as a whole with 30 in figure 3, having an inlet 31 and an outlet 32. According to the invention, at least a portion of the first supply duct 13 - indicated with 13a in figure 3 and hereinafter referred to as â € œportion of heat exchangeâ € - extends inside the storage container 30, to form with it a substantially static type of heat exchanger.

The machine 1 further comprises first controllable means, for supplying the container 30 with water used in the aforementioned first operating step, and second controllable means, for evacuating the water contained therein from the container 30. In the example of Figure 3, the aforesaid first controllable means include the washing pump 22 and the valve means 23, in combination with a duct 26 which extends between the valve means 23 and the inlet 31 of the container 30. Always with reference to the illustrated example, the second controllable means include an additional drain pump, indicated with 27, whose suction branch is connected to the outlet 32 of the container 30 and whose delivery is instead connected to a duct 28, which can be connected to the exhaust duct 25 (as shown) or be parallel to it. In the example, the conduit 28 is connected to the conduit 25 and a non-return valve 28a is provided on it; a similar non-return valve 25a is also provided on the pipe 25 in its section upstream of the connection with the pipe 28. It should be noted that the non-return functions of the valves 25a and 28a can be fulfilled or integrated in the pumps 24 and 27, according to the technique in itself known in the industry.

The machine 1 has, in a preferred embodiment, a second duct, for feeding water from the water network into the tank 3 R. In the embodiment of Figure 3, this second supply duct, indicated with 33, Ã ̈ in parallel with the heat exchange portion 13a of the first supply duct 13. In a different embodiment, described below (Figure 15), the second supply duct 33 is substantially parallel to the entire first supply duct 13.

Respective valve means, indicated by 34, are operatively associated with the second supply duct 33. In the example of Figure 3 these valve means 34 are substantially located at a point where the second duct 33 is derived from the first duct 13 and may include a device including two solenoid valves or a diverter device, controllable in such a way that the water flow coming from the water mains R, after passing the devices 15 and 16, is alternately directed towards the heat exchange portion 13a of the first duct 13 or in the second duct 33.

In one embodiment the control system of the machine 1 is configured for

- control the aforementioned first means - represented here by the washing pump 22 and the valve means 23 in combination with the duct 26 - to discharge the hot water that was used in the aforementioned first operating phase into the storage container 30, - check the valve means 34 associated with the second supply duct 33, to feed into the tank 3 water drawn directly from the water network R, for the purpose of carrying out the second operating phase: in this way, at least during the execution of the second operating phase, the Hot water that has previously been discharged into the storage container 30 transfers heat to the water that is contained in the heat exchange portion 13a of the first supply duct 13,

- check the drain pump 24 for the purpose of evacuating from the machine the water used in the second operating phase (whether it is heated or unheated water), at the end of the latter,

- controlling the valve means 17 associated with the first supply duct 13 to allow the transfer into the tank 3 of the water contained in the heat exchange portion 13a of the first supply duct 13, and

- control the second means - represented by the additional pump 27 in combination with the relative pipe 28 - for the purpose of evacuating the water contained in the storage container 30 towards the drain 25.

The machine 1 is therefore advantageously able to recover part of the heat of the water used in the first operating phase, for the benefit of the water to be used during the third operating phase. In fact, at the end of the first operating phase, the hot water previously used in the tank is conveyed to the container 30, which is crossed by the heat exchange portion 13a of the first duct 13, which contains decalcified water from the water network R, at the network temperature. The control system then commands the opening of the valve means 17 and 34, so as to make the water coming from the water network R flow directly into the tank, through the second supply pipe 33, which is substantially at the temperature network, for the implementation of the second operational phase.

In this way, the hot water present in the container 30 heats the water present in the portion 13a of the first duct 13, under substantially static heat exchange conditions. The adequate heat exchange time is allowed by the fact that the machine 1, in the meantime, carries out the second operational phase, using the water loaded into the tank at the network temperature. Indicatively, if the second phase is represented by a rinse, its duration can be between 10 and 15 minutes. During the time in which the heat exchange takes place between the water contained in the container 30 and that contained in the portion 13a of the duct 13, the machine 1 here carries out an operational phase of wetting the dishes: this is advantageous, as it avoids the risk that any washing detergent residues can dry on the dishes themselves.

After the second operational phase, for example after the step of unloading the relative unheated water from the tank 3, a step of discharging the water present in the container 30 is preferably performed, by activating the additional pump 27 by the system control. The valve means 17 associated with the first supply duct 13 are then opened, while the valve means 34 are in the inoperative condition, ie they obstruct the second duct 33. In this way the water present in the heat exchange portion 13a of the first duct 13, now partially heated, is pushed into the tank 3 by the same pressure of the water network R: the new water entering the network R then replaces the heated one which is fed into the tank. This heated water that has reached the tank 3 can then be subjected to a further heating phase up to a predetermined temperature, by means of the traditional means of heating the machine, for the purpose of carrying out the third operating phase.

It will be appreciated that in this way it is possible to obtain energy savings, particularly by reducing the duration of the electrical supply necessary for the heating means to bring the water loaded into the tank to the aforementioned predetermined temperature, and overall reducing the program time. . An induced advantage is that the part of the water coming from the network R remains in the supply ducts 13 and 33 until the execution of a subsequent washing cycle carried out by the machine 1, with this undergoing a certain increase in temperature (for example example from about 15 ° C of the R network to about 20 ° C due to the ambient temperature), which also has positive effects on the reduction of energy consumption.

As previously seen, in a preferred embodiment, the filtering system including the filters 6-8 having meshes of different sizes is associated with the collection well 5. It will therefore be appreciated that the means represented by the pump 22, the valve means 23 and the duct 26 allow the container 30 to be fed with water filtered by at least two of the aforementioned filters. The hot water which is conveyed to the container 30, even if it is water already used for a treatment of the dishes, is therefore substantially filtered water in a fine way, and therefore tends to be free of significant residues of dirt. In this way the risk of clogging of the storage container 30 and of the ducts associated with it is drastically reduced.

As mentioned, the means for feeding the container 30 preferably comprise a device 23 for the alternate feeding of at least two sprinkler members 18 and 19 of the sprinkler system of the machine. In a preferred embodiment, this device 23 includes an outlet which, through the duct 26, is connected to the inlet 31 of the container 30, as well as a controllable shutter member, capable of assuming a plurality of alternative positions, in at least one of which the aforementioned exit is open. In this way, the control of the supply of the accumulation container 30 can be carried out by exploiting for the most part means that must in any case be provided on board the machine, and in particular in its base 2 or space 2a, to the advantage of reducing the number of components and overall dimensions.

An example of a device 23 that can be used for this purpose is shown schematically in figure 4. The device 23, like similar devices according to the prior art, has a casing 23a provided with an inlet 23b, intended for connection with the delivery of the washing pump. 22, and two main outlets 23c and 23d, connected to the supply ducts 21 and 20 of the upper sprinkler and the lower sprinkler, respectively. Inside the casing 23a there is a movable shutter or distributor member, which can be operated by a relative actuator, isolated from the fluid, to assume at least a first position for opening both outlets 23c and 23d, and at least one second position, for opening the outlet 23c and closing the outlet 23d and / or vice versa, all according to the known technique. For example, the aforesaid distributor member can have the shape of a disk or circular sector, with one or more through holes, and be mounted movably in front of the aforesaid outlets 23c and 23d.

According to a characteristic provided in an embodiment, the device 23 is configured in such a way that the casing 23a additionally defines a further outlet, indicated with 23e, which preferably has a lower passage section than the outlets 23c and 23d, to which the inlet of the supply duct 26 of the storage container 30 is connected.

In one embodiment, the opening and closing of the outlet 23e is controlled by means of the aforementioned obturator member or internal distributor of the device 23. In this way, when the water must be directed towards the container 30, the outlet 23e is opened (the outlets 23c, 23d can be indifferently open or closed), so that - given the active condition of the washing pump 22 - the volume of water contained in the tank is progressively transferred into the container 30 (such a case is represented in figure 15).

In a different embodiment, as exemplified in Figure 3, the outlet 23e is always in fluid communication with the inlet 23b of the device 23, regardless of the operating position of the aforementioned distributor member. In this case, the first end of the duct 26 is connected to the outlet 23, the second end of which is connected to the inlet 31 of the container 30, with the interposition of further valve means 40, of any known concept.

A possible embodiment of a valve usable for this purpose is exemplified in figure 5. The valve, indicated by 40, is preferably an open / closed type valve, which includes a connection body 40a having an inlet 40b, to which The duct 26 is connected, and an outlet 40c, connected with the interposition of suitable sealing means to the inlet 31 of the container 30. Between the inlet 40c and the outlet 40d, inside the body 40a, a shutter is operative, which can be moved by means of an actuator which, in the exemplified embodiment, is an electro-thermal actuator 41, of a per se known type. The valve 40 can therefore be actuated by the control system independently of the device 23 and is of the normally closed type: therefore, in the absence of power supply to the actuator 41, the pipe 26 is not in fluid communication with the container 30.

In this embodiment, when the heated water present in the tank, used in the first operating phase, must be supplied to the container 30, the control system commands the opening of the valve 40, with the washing pump 22 active. In this way, and regardless of the operating position of the internal distributor member of the device 23, the water is progressively fed into the duct 26, and therefore into the container 30.

Preferably, as seen, the means for evacuating the water contained therein from the container 30 include a pump 27, operatively interposed between the outlet 32 of the container 30 and a discharge duct 25 of the machine. The evacuation of the water therefore takes place preferably in a forced manner, and this ensures the emptying of the container 30, at the same time reducing the risk of clogging and dirt deposits within the container itself. For this purpose the outlet 32 is preferably located in a low point of the container 30.

The useful capacity of the heat exchange portion 13a of the supply duct 13 can be substantially the same or less than the useful capacity of the storage container 30. In general terms, the overall useful capacity of the exchanger represented by the container 30 and the portion of thermal exchange 13a can be substantially equal to the volume of water necessary for the execution of two phases of the washing cycle (preferably from 5 to 6.7 liters).

In one embodiment, the container 30 has a useful capacity substantially equal to or slightly greater than the volume of water which is used in the course of the first operating phase. In a preferred embodiment, this useful capacity is between 2.7 and 3.7 liters, preferably between 2.9 and 3.5 liters, most preferably between 3 and 3.3 liters, while the portion 13a of the first duct 13 it has a useful capacity between 2.2 and 3.4 liters, preferably between 2.4 and 3.2 liters, most preferably between 2.3 and 3 liters.

The useful capacity of the container 30 can also be less than the volume of water used during the first operational phase. For such a case, the control system will - after the filling step of the container 30 - activate the drain pump 24 to evacuate any residual water from the tank 3 and / or from the well 5.

In general terms, therefore, in the context of the heat exchanger consisting of the storage container 30 and the heat exchange portion 13a of the duct 13, the quantity of hot water can be greater than the water at the temperature of the water network R, and this favors the efficiency of the heat exchange and the energy gain. Naturally this means that, in such an implementation, the third operational phase of the treatment program will be carried out with a quantity of water lower than that used for the execution of the first operational phase. However, this does not face particular problems, considering for example that currently the washing phase in the strict sense of a load of dishes is often performed with a greater quantity of water than that used for the execution of a subsequent hot rinse phase of the same treatment program, driving the washing pump at a lower speed during rinsing. In a possible implementation, for example, the third operating phase is carried out for about half of its duration by operating the pump 22 at reduced speed and / or using only one of the sprinklers 18 and 19.

In one embodiment, the accumulation container 30 extends in a generally rear area of the base 2 or of the housing space 2a, preferably transversely with respect to the lateral sides of the base or of the machine structure, and at least behind the collection well 5, to the washing pump 22, to the drain pump 24 and to the descaling device 16 (if the latter is provided on the machine). This arrangement makes it possible to make the most of the space available inside the base and to maximize the size of the storage container. Such an arrangement is exemplified in schematic form in figure 6, where the device 23 for the alternating supply of the sprinklers, the valve 40 and the pump 27 are also visible. In the figure, F indicates an anti-interference filter, provided for reasons of electromagnetic compatibility, and with EC an electronic card that implements part of the machine control system. The figure also shows the air jump device 15 which, according to the known technique, can be associated with a side wall of the tank 3.

It will be appreciated that, in this way, in the rear part of the base 2, or in any case of the structure of the machine, there is always a volume of water, which is at least equal to that contained in the portion 13a of the supply duct 13, this volume of water water being able to help counterbalance the machine 1. In this regard, it should be remembered that current domestic dishwashers have, for various reasons, a relatively light load-bearing structure, so there is a risk - particularly in the case of free-standing machines - that the machine tends to tip forward, when its door is opened and the relative baskets with the load of dishes are extracted from the tank: for this reason it often becomes necessary to equip the machine with suitable counterweight masses. The proposed solution allows to eliminate such counterweights or, at least, to reduce their volume and mass.

With reference to this aspect, and when the storage container 30 is not used as an active part of a drying system of the machine, the control system can be configured to control the aforementioned second means (in particular the additional pump 27) in order to to evacuate the water contained in the container 30 only after the start of a treatment program which temporally follows the treatment program during which water was supplied to the container itself. Thanks to this feature, the volume of water that acts as a counterweight can be increased, with the ensuing advantages.

As previously mentioned, according to the invention, the machine 1 comprises a drying circuit, preferably of the substantially closed type, and the accumulation container 30 is used as an active part of the drying system.

As shown schematically in Figure 3, the container 30 has at least a first inlet 36 for the air, preferably in an area higher than the minimum level that can be reached by the water in the container itself, and at least one outlet for the air 37, preferably in an upper area thereof and in fluid communication with the inside of the tank 3.

In the example illustrated, the drying circuit therefore includes the hollow body 10, to which a fan is operationally associated, schematized in 50. In the example, the fan 50 is associated with the hollow body 10, with its branch suction which is in fluid communication with an opening in the upper wall of the tank and with its delivery branch which is instead connected to the inlet of the hollow body 10. The outlet of the hollow body 10 Ã On the other hand, it is in fluid communication with the air inlet 36 of the storage container 30, whose air outlet 37 communicates with the inside of the tank 3. In this realization, the inlet for the drying air in the tub, it can be defined, for example, in correspondence with the lower wall 3b of the tub. This inlet preferably includes a passage in the wall 3b, and a tubular chimney 38, of per se known design, which extends through this passage. In general, such a chimney 38 has an upper end and a lower end that open on opposite sides of the wall 3b, the upper end being at a height higher than the maximum level reachable by the water in the course of the washing or rinsing operations performed by the machine 1. Preferably, a hood or lid is associated with the upper end of the chimney 38, which defines a substantially shielded or labyrinth path, while its lower end is connected in communication of fluid the air outlet 37 of the container 30.

At least one of the treatment programs envisaged by the machine according to the invention includes a stage for drying the dishes, which is performed at a time subsequent to the evacuation of the water from the storage container 30, or in any case when the container 30 It is essentially empty.

In the drying phase, the fan 50, controlled by the control system, sucks in the humid air present in the tank 3 and the force in the hollow body 10, downwards. Advantageously, the hollow body 10 can be configured to perform condensation functions, for example by providing inside it a tortuous path for the air. At the exit from the hollow body 10, the air enters the storage container 30, through its inlet 36, and then returns to the tank, through the outlet 37 and the chimney 38: in this way, the flow of The still relatively hot air that passes through the container 30 touches the heat exchange portion 13a of the duct 13. In this phase, the portion 13a contains water which is substantially at the temperature of the water network R and this favors the condensation of the still humidity present in the air that has been extracted from the tank by means of the fan 50. The condensation of this humidity determines the formation of drops of water, which are collected in the container 30.

In a particularly advantageous embodiment of the invention, it is envisaged that, before starting the drying phase or during this phase, the control system controls the valve means 17 associated with the first supply duct 13 to cause short openings. Thanks to these short opening pulses of the solenoid valve 17, modest quantities of water at the temperature of the network R reach the initial section of the heat exchange portion 13a of the duct 13, in order to increase the condensation efficiency of the Humidity present in the circulating air.

To better clarify this concept, reference should be made to Figure 3, in which the container 30 is visible, with the heat exchange portion 13a of the duct 13 inside, substantially configured as a serpentine or in any case having a substantially tortuous course: as you can see, the inlet for air 36 is substantially close to the initial section of portion 13a. The air that penetrates from inlet 36, still relatively hot, first hits the aforementioned initial section of portion 13a, basically at the network temperature: as mentioned, this favors the condensation of the humidity present in the air. However, the incoming air is relatively hot and this progressively determines the heating of the water contained in the aforementioned initial section of the portion 13a. For this reason, by opening the solenoid valve 17 for a short time, it is possible to replace this water partially heated by the air with new water, substantially at a lower temperature, which fills the first or first coils of the portion 13a: in this way, the condensation efficiency can be restored. From this point of view, in the context of the drying phase, a plurality of the aforementioned short openings of the solenoid valve 17 can be provided, temporally distanced from each other and controlled by the control system (the times can be for example pre-set, based on experimental investigations).

With this method of operation, a passage of water in the tank is determined during drying, but the relative volume is very modest, in the order of 200-400 cc, and in any case not greater than a liter. Moreover, the presence of this volume of water added to the tank is advantageous, as it allows the creation of a sort of â € œwater capâ € in correspondence with the well 5, which avoids dispersion of the air flow in this area.

In a preferred embodiment, the portion 13a of the first supply duct 13 has a substantially tortuous course. This allows to increase the capacity of this portion 13a and to significantly increase the heat exchange surface between the heated water fed to the container 30 and the water present in the portion itself.

Again preferentially, the portion 13a of the supply duct 13 is made up of a plurality of modular hollow elements, coupled together in fluid communication and each having an inlet and an outlet. In this way, the portion 13a of the first duct 13 can be obtained by assembling together a plurality of components, connecting them in series by connecting the outlet of such an element with the inlet of the next element in the series, and with the relative major faces of the various hollow elements preferably spaced apart. In this way the hollow elements can be given a shape which is convenient for the purposes of heat exchange, the construction of the heat exchanger is simplified and the heat exchange surface can be maximized.

Figure 7 illustrates a possible embodiment of the storage container 30, with inside the relative heat exchange portion 13a, not visible, of the first supply duct 13.

The container 30 has a longitudinally extended body, preferably formed of at least two parts of plastic material, although a metal embodiment is not excluded in principle. In the example, the body of the container 30 consists of a lower part 30a and an upper part 30b, tightly coupled to each other in correspondence with respective flange parts, for example heat-sealed or fixed to each other by means threaded and interposition of suitable sealing means.

The body of the container 30 has, preferably in one of its side walls, the respective inlet 31 and outlet 32 for the water. Preferably, the inlet 31 is located in a generally upper region of the container 30, while the outlet 32 - to which the pump 27 is associated - is located in a lower region of the container itself. From figure 8 it can be seen how, in a preferred embodiment, the bottom wall of the container 30, or of its lower part 30a, is at least slightly inclined so as to favor the flow of water towards the outlet 32. In Figure 7 also shows the inlet 36 and the outlet 37 for the drying air.

In the body of the container 30, for example in its upper part, passages are defined to allow the connection, upstream and downstream of the container 30, of the heat exchange portion 13a to the supply duct 13. One of these passages, in correspondence with the which suitable sealing means are preferably operative, is indicated with 30c in figure 7, for the branch of the duct 13 which is upstream of the portion 13a. In the example shown, the passage for the branch of the duct 13 which is downstream of the portion 13a is represented by the outlet 37 for the drying air: however, nothing prevents the provision of a special passage similar to the one indicated with 30c.

Figure 9 shows one of the hollow modular elements used to make, in a preferred embodiment, the heat exchange portion 13a of the supply duct 13. The represented element, indicated as a whole with 50, is of a first type, with a hollow body preferably formed of plastic material, although a metal construction is not excluded in principle. In the example, the body of the element 50 has a generally annular shape with a protruding upper portion 50a. In this upper portion 50a, in correspondence with a side face or extremity of the body, here the left face, a first connection 51 is defined; a second fitting 52 is defined in an intermediate zone of the opposite side face, here the right face, preferably just below the fitting 51. Figure 10 instead illustrates a hollow modular element of the second type, indicated with 50â € ™. In general terms, the structure of element 50 'is similar to that of element 50, but with a symmetrical or inverted arrangement of the relative fittings: in essence, therefore, the upper connection, here indicated with 51' it is located on the right face of the body of element 50 ', while the second connection, not visible but later indicated with 52', is now on the left face, not visible.

Inside the cavity of the elements 50, 50â € ™ at least one intermediate closing wall is defined, visible in figure 11 for an element 50, where it is indicated with 53. This wall 53 essentially extends into the annular part of the body of the hollow element, above the intermediate fitting 52 or 52â € ™. In any case, wall 53 is defined in such a way that the water passing through the hollow body cannot pass directly between the two connections following the shortest path, but must instead necessarily travel the shortest path. long, ie for the most part the aforementioned annular part, as exemplified by the arrow W in figure 11 for an element 50 (in the case of an element 50â € ™, the path of the water will be the opposite of an element 50, ie from the connection 51â € ™ to junction 52â € ™).

Preferably, the diameter of the fitting 51 is slightly greater than the diameter of the fitting 51â € ™, or vice versa, so that they can be inserted tightly into each other, with the possible interposition of a gasket or a applied sealant, for example silicone. For the same reasons, the diameter of fitting 52 is preferably slightly larger than the diameter of fitting 52â € ™, or vice versa.

In this way, as can be understood, a plurality of elements 50 and 50â € ™ can be assembled alternately to each other, to create the heat exchange portion 13a of the supply duct 13, as exemplified in Figures 8 and 12. The connection of the elements is in series and is achieved by coupling the output of an element to the input of the next element. Such a connection method is clearly visible in figure 13: in this partial and schematic section you can see the connection of the fittings 52â € ™, which here act as outlets for the elements 50â € ™, to the fittings 52, which here act as inputs of the elements 50, as well as the connection of the fittings 51â € ™, which here act as inlets for the elements 50â € ™, to the fittings 51, which here act as outlets for the elements 50.

In the example shown, at the two ends of the heat exchange portion 13a there are modular hollow elements 50c and 50câ € ™ with a modified shape with respect to the elements 50 and 50â € ™. The hollow element indicated with 50c is for the most part similar to the elements 50, but it lacks the fitting 52, which is replaced by a fitting 52a which is located in the upper part of the element itself. Similarly, the hollow element indicated with 50câ € ™ is for the most part similar to the elements 50â € ™, but it lacks the fitting 52â € ™, which is replaced by a fitting 52aâ € ™ which is located in the upper part of the element itself. The use of hollow elements 50c and / or 50câ € ™ is preferred if you want to have the entry and exit of the portion 13a in correspondence with the upper area of the container 30 and / or maximize the useful dimensions of the same portion 13 within the container 30. Moreover, there is nothing to prevent the use, at the two opposite ends of the heat exchange portion 13a, two hollow elements 50 and 51â € ™, in which case the passages for connecting the portion 13a to the sections of the upstream and downstream duct 13 will be provided in the two opposite ends of the container 30 (for the upstream section, the inlet 36 may also be used for drying air.

As you can guess, with the illustrated arrangement, the water coming from the water network R penetrates into element 50câ € ™ through its fitting 52aâ € ™, filling it, and then passes into the next element 50, filling it in turn, and so on up to the last element of the series, here represented by the element 50c, with its connection 52a which acts as the outlet of the portion 13a. Thanks to the presence of the wall 53 of the hollow elements 50, 50â € ™, 50a, 50aâ € ™ the connection of the latter in series practically simulates a serpentine duct, with a sequential filling of the elements themselves.

Obviously, after the first operation of the machine 1 following installation, the heat exchange portion 13a, ie the hollow elements that constitute it, are always basically filled with water. In fact, it is evident that, when the solenoid valve 17 of figure 3 is open and also the valve means 34 are in the open condition of the duct 13, the water coming from the water mains R, at the pressure of this last, it will in any case keep the duct 13 full of water, downstream of the blowing device 15; when the solenoid valve 17 closes and the duct 13 switches to close by the valve means 34, the branch of the duct downstream of said means 34 will in any case remain full of water.

Figure 14 exemplifies, by means of a section in lateral elevation, the condition that occurs when the heat exchange portion 13a and the container 30 are both full of water. Basically, the tortuous portion 13a formed by the hollow elements - initially containing unheated water CW - is substantially completely immersed in the HW heated water present in the container 30. During the execution of the second operating phase of the treatment program (ie the phase carried out with water loaded into the tank through the second supply duct 33) the heat exchange takes place between the two HW and CW fluids, with the first transferring heat to the second. It will be appreciated that, in the particularly advantageous embodiment illustrated in Figures 7-14, the heat exchange surface is very high, particularly in virtue of the fact that also the larger faces of the hollow elements 50, 50â € ™, 50a, 50aâ € ™ are between spaced them apart. As an indication, with respect to a known machine of the type having an accumulation container leaning against a side wall of the tank, the preferential solution proposed allows to increase between 3 and 4 times the width of the heat exchange surface.

As previously mentioned, the exchanger consisting of the container 30 and the heat exchange portion 13a can also be used for the execution of a drying phase, and in this case the container 30 has an inlet 36 and an outlet 37 for the air. When the heated water is fed to the container 30, at the end of the first operating phase of the program, there is no risk of water overflowing through these inlets and outlets. If for any reason (for example a malfunction) a volume of water exceeding its useful capacity is added to the container 30, the excess water will be able to flow freely back into the tank, through the outlet 37 and the chimney 38. From the chimney 38. On the other side, even in normal conditions, part of the heated water conveyed to the container 30 will be able to flow into the air inlet 36, and eventually rise along the drying circuit (in particular along the hollow body 10, in the ™ example): it is however clear that, when the container 30 is unloaded, this water present in the drying circuit will also be evacuated.

In one embodiment, the valve means associated with the first supply duct 13 and the valve means associated with the second supply duct 33 can be integrated in the same device. This solution also simplifies the assembly of the machine and allows a reduction of the overall dimensions, particularly in the area of the machine base. Such a solution is exemplified in figure 15, where the same reference numbers of the previous figures are used, to indicate elements technically equivalent to those described above.

In the embodiment in question, the loading solenoid valve 17 and the valve means 34 of figure 1 are replaced by a single device 17 'controllable by the machine control system, such as for example a device including an inlet and two controlled outputs by respective shutter means, for example two solenoid valves. As can be seen, in this case, the second supply duct 33 is substantially parallel to the first supply duct 13.

The operation of the machine 1 in figure 15 is similar to that previously described, with the difference that, for the purpose of filling the tank with the water necessary for carrying out the first operating phase, respectively the third operating phase, of the first program treatment, the control system controls the device 17â € ™ so that the duct 13 opens, keeping the duct 33 closed. way to open the duct 33, keeping the duct 13 closed.

The second supply duct 33 can be derived from the first supply duct downstream of the decalcifying device 16, as in the embodiment of figure 3, or upstream thereof, in which case the valve means 34 can be provided between the air jump 15 and the decalcifying device 16. In the first case, the second operational phase of the first treatment cycle will be performed with decalcified water, while in the second case with water at the degree of hardness of the water mains. This is not a source of particular problems, given that the second operational phase is carried out with unheated water, substantially at the temperature of the network R, ie at a temperature that does not cause the precipitation of limestone. This also reduces the use of descaling resins, and therefore of the salt necessary for their regeneration. Moreover, the presence of a water softener is not strictly essential.

Figure 15 has also taken to explain a further possible variant of implementation. The air-blowing device, when necessary for regulatory reasons, can be provided along at least one of the first supply duct 13 and the second supply duct 33. In the case of the embodiment of figure 3, the air-blowing device 15 is located along the first supply duct 13, upstream of the decalcifying device 16, with the second supply duct 33 which branches off from the first duct 13 downstream of the device 15. In this embodiment, it is therefore possible to reduce the number of components of the car. Moreover, in a different embodiment, exemplified in figure 15, both the supply ducts 13 and 33 can each be provided with an air-blowing device. In the example shown, reference 15 'indicates a device that includes two distinct jumps in the air, one for the duct 13 and the other for the duct 33. As can be understood, in this embodiment, the second operational phase is performed with non-descaled water.

Figure 16 illustrates a further variant of implementation, which differs from the embodiment of Figure 3 substantially due to the absence of the valve device 23 for the alternating power supply of the sprinklers 18 and 19. In this solution the delivery of the washing pump 22 is connected directly to the pipes 20 and 21, so that the sprinklers 18 and 19 are always fed at the same time.

In this solution, for example in any point of the pump scroll (or in correspondence with its delivery) an outlet is defined, to which the inlet of the duct 26 is connected for the supply of the container. accumulation 30, on which duct a relative valve means 60 is operative, for example a valve similar to the valve 40 of Figure 5, of the normally closed type. In this embodiment, therefore, when the hot water used for the purpose of carrying out the first operating phase of the program must be used in the container 30, the control system commands the opening of the valve 60 and activates the pump 22. In this way, the water present in the tank 3 is progressively sent into the container 30. As in the previous embodiments, this step of discharging the water content of the tank 3 into the container 30 can have a predetermined duration, such as to guarantee emptying the tank, or being enslaved to the vacuum level of a pressure switch, in order to avoid cavitation noise.

Naturally, the variants described with reference to figures 15 and 16 can be combined in various ways and with respect to the embodiment of figure 3. It is clear that numerous variants are possible for the person skilled in the art to the dishwashing machine described as an example, without for this to go out of the scope of the invention as defined in the attached claims.

In the previously described embodiments, the cold rinsing phase which constitutes the second operating phase can be replaced by a phase essentially consisting in filling the tank with water at the network temperature, through the duct 33, and recirculating by means of the washing pump 22 ( for example using the lower sprinkler only) to clean the bottom wall 3b of the tank 3 and the well 5. The second operating phase can also be a hot phase.

In a particularly advantageous variant, at least one of the storage container 30 and the heat exchange portion 13a of the first supply duct can be at least partially integrated into a machine base, or at least partially formed in a single piece with it.

Claims (15)

CLAIMS 1. A dishwashing machine comprising a base (2), a washing tank (3) supported by the base (2) and a control system (EC), in which - the base (2) defines a housing space (2a) for operating components of the machine (1), - the tank (3) has a lower wall (3b) to which a collection well (5) is associated which protrudes inside the housing space (2a), - a washing pump (22) is housed in the housing space (2a), in fluid communication with the collecting sump (5) and designed to feed a sprinkler system (18, 19) operating inside the tank ( 3), and a drain pump (24), in fluid communication with the collecting sump (5) and designed to forcefully evacuate the water from the tank (3) through a drain duct (25), - the machine (1) has connection means (14), configured for connection to a water mains (R) and connected via a first supply duct (13) to a water inlet in the tank (3), to the first supply conduit (13) being operatively associated with valve means (17, 34; 17â € ™), - the control system (EC) is designed to control the execution of a plurality of dishes treatment programs, including at least a first treatment program that includes a plurality of operating phases, - wherein the machine (1) further comprises - a storage container (30) having a water inlet (31) and a water outlet (32), - first means (22, 23, 26, 40; 22, 23, 26; 22, 26, 60), for supplying the storage container (30) with water, and second means (27, 28), for evacuating from the container of accumulation (30) of water contained in it, - a fan (50) having an intake branch in fluid communication with the inside of the tank (3) and a delivery branch, characterized by the fact that - at least a portion (13a) of the first supply duct (13) extends inside the storage container (30), - the first treatment program includes a drying phase that can be carried out at a time subsequent to the evacuation of the water from the storage container (30), or in any case in a substantially empty storage container condition (30), - the storage container (30) has at least one inlet for the air (36), in fluid communication with the delivery branch of the fan (50), and an outlet for the air (37), in fluid communication with the inside of the tank (3), - the control system (EC) is configured to control the fan (50) during the drying phase, to cause the passage of a flow of air in the storage container (30), between the inlet for the Air (36) and the air outlet (37), in such a way that the air flow touches the said portion (13a) of the first supply duct (13). The dishwashing machine according to claim 1, wherein the control system (EC) is arranged to control one or more short openings of the valve means (17; 17â € ™) associated with the first supply duct (13) before and / or during the drying phase. The dishwashing machine according to claim 1 or claim 2, wherein - at least one said treatment program includes: - a first operational phase, particularly a washing phase, - a second operating stage, particularly a first rinsing stage, - a third operating stage, particularly a second rinsing stage, - the machine (1) comprises a second supply duct (33), parallel to one of the first duct supply duct (13) and said portion (13a) of the first supply duct (13), to feed water into the tank from the water mains (R), with the second supply duct (33) being operatively associated with valve means (17â € ™ ; 34), - the control system (EC) is configured for - controlling said first means (22, 23, 26, 40; 22, 23, 26; 22, 26, 60), to discharge the heated water used in the first operating phase into the storage container (30), - control the valve means (17â € ™; 34) associated with the second supply duct (33) to feed water from the water mains (R) into the tank (3), for the purpose of carrying out the second operating phase, in such a way that therefore, during the execution of the second operating phase, the heated water discharged into the storage container (30) transfers heat to the water contained in said portion (13a) of the first supply duct (13) in substantially static conditions , - check the drain pump (24) to drain the water used in the second operating phase from the tank (3), - controlling the valve means (17, 34; 17â € ™) associated with the first supply duct (33) to allow the transfer into the tank (3) of the water contained in said portion (13a) of the first supply duct (13 ), And - check said second means (27, 28) for the purpose of evacuating the water contained therein from the accumulation container (30). The dishwashing machine according to any one of the preceding claims, in which the collection well (5) is associated with a filtering system including a plurality of filters (6, 6a, 7, 8) having meshes of different sizes and in which said first means (22, 23, 26, 40; 22, 23, 26; 22, 26, 60) are designed to feed the storage container (30) with water filtered by one or more filters (6, 6a, 7, 8 ) of said plurality, said first means including the washing pump (22). 5. The dishwashing machine according to claim 4, wherein said first means (22, 23, 26, 40; 22, 23, 26; 22, 26, 60) comprise an arrangement for alternating power supply (23, 40) of at least two sprinkler members (18, 19) of the sprinkler system, said arrangement (23, 40) including an outlet (23e) connected to the water inlet (31) of the storage container (30) and a controllable member (40), capable of assuming a plurality of alternative positions, including an opening position of said outlet (23e) of the arrangement for alternating power supply (23, 40). 6. The dishwashing machine according to any one of the preceding claims, wherein said second means include a pump (27) operatively interposed between the water outlet (32) of the storage container (30) and the discharge duct (25 ). The dishwashing machine according to claim 1, wherein - the storage container (30) has a useful capacity of between 2.7 and 3.7 liters, preferably between 2.9 and 3.5 liters, most preferably between 3 and 3.3 liters, and - said portion (13a) of the first supply duct (13) has a useful capacity of between 2.2 and 3.4 liters, preferably between 2.4 and 3.2 liters, most preferably between 2.3 and 3 liters . The dishwashing machine according to any one of the preceding claims, in which said portion (13a) of the first supply duct (13) has a substantially tortuous or serpentine shape. The dishwashing machine according to claim 8, wherein said portion (13a) of the first supply duct (13) comprises a plurality of modular hollow elements (50, 50â € ™), coupled together in fluid communication and having each an entrance (52, 51 ') and an exit (51, 52'). The dishwashing machine according to any one of the preceding claims, in which the valve means associated with the first supply duct (13) and the valve means associated with the second supply duct (33) are integrated in the same device (17â € ™) , such as a device including two valves. 11. The dishwashing machine according to any one of the preceding claims, in which an air blow device (15; 15â € ™ ). The dishwashing machine according to claim 1, in which the accumulation container (30) is housed in the housing space (2a) and preferably extends into a rear area of the base (2), in a rear position with respect to the collection (5), to the washing pump (22) and to the drain pump (24). 13. The dishwashing machine according to claim 12, wherein in the housing space (2a) there is also housed a decalcifying device (16) having an inlet, in fluid communication with the connecting means (14), and a outlet, in fluid communication with the first supply duct (13), the accumulation container (30) extending rearward also to the decalcifying device (16). The dishwashing machine according to any one of the preceding claims, wherein at least one of the storage container (30) and said portion (13a) of the first supply duct (13) is at least partially integrated in the base (2), or at least partially formed in one piece with it. 15. A method for drying dishes in a domestic dishwashing machine (1) having a washing tank (3), a water storage container (30), a drying system (10, 50) including a fan (50), a duct (13) having associated valve means (17; 17â € ™) for feeding water into the tank (3) from a water network (R), in which at least a portion (13a) of the said duct (13) extends inside the storage container (30), the method comprising carrying out a phase of drying dishes in a time subsequent to the evacuation of the water contained in the storage container (30), the drying phase comprising operating the fan (50) to cause the transit of a flow of forced air in the storage container (30), between a respective inlet for the air (36) in fluid communication with a delivery of the fan (50) and an outlet for the air (36, 37) in fluid communication with the inside of the tank (3), in such a way that the air flow touches the said portion (13) of the said duct (13), before and / or during the execution of the drying, one or more short openings of the valve means (17; 17â € ™) associated with said duct (13) being preferably made.