EP1319360A1

EP1319360A1 - Domestic dishwasher with a front loading door having a recessed panel and a detergent measurer/dispenser supported by the upper rack

Info

Publication number: EP1319360A1
Application number: EP01830746A
Authority: EP
Inventors: Silvano Fumagalli
Original assignee: Candy SpA
Current assignee: Candy SpA
Priority date: 2001-12-06
Filing date: 2001-12-06
Publication date: 2003-06-18
Anticipated expiration: 2021-12-06
Also published as: DE60102828T2; EP1319360B1; DE60102828D1

Abstract

Domestic dishwasher machine, with a front loading door (3), wherein the detergent measuring/dispensing device (15) is housed in the washing chamber (1) and is supported by the upper rack (16) in a dead zone thereof, wherein the withdrawal of the detergent takes place with the entry of a decalcified water flow into the device (15), at the start of a washing step, and an additive measuring/dispensing device (13), with the relative reservoir (12), is housed in the interspace between a side wall of the washing chamber and a corresponding outer wall, so that the counterdoor (7) for closing the washing chamber, free from the presence of these devices, is drawn into recess for the whole of its height and increases the useful volume of the washing chamber.

Description

The present invention relates to a domestic dishwasher machine, with a front loading door, a counterdoor entirely drawn into recess and a detergent measurer/dispenser supported by the upper rack.
It is known that in domestic dishwasher machines there is the serious problem of balancing the requirement of a high load volume of the washing chamber with an outer volume which is small and standardised, in terms of sizes, to allow built-in installation under a work surface, in combination with other functional modules.
Generally, control and programming devices, as well as dispenser devices of detergent and of washing additives, which must be actuated by the user, are all housed in the interspace comprised between a front panel of the loading door and a counterdoor panel which seals closed the washing chamber.
Command and programming devices can therefore be accessed either directly on a front instrument panel or on the upper edge of the door, with a limited opening of the door.
Dispenser devices of the detergent and of possible additives, on the other hand, can be accessed, for the loading thereof, with the complete opening of the door.
If, on the one hand, this arrangement gives some advantages, like the fact that with a single electromagnetic actuator it is possible to activate in subsequent steps of the wash cycle both the detergent dispenser device and the rinse aid additive dispenser device, in general forming a single integrated device, it also has various drawbacks, listed here:

firstly the size of the dispensing devices determines the thickness of the entire interspace, with it not being possible, with drawing operations of the counterdoor, to obtain selective housing space, having a different depth to take account of the different sizes of the components.

The drawing operation allows a single recess to be obtained, surrounded by a frame, only in the lower part of the counterdoor, arranging the different components in the interspace thus left in the upper part of the door.
This recess increases to some extent the useful volume of the washing chamber but most of the interspace volume between door and counterdoor is wasted.
Moreover, from the ergonomic point of view, the loading operations of the detergent and of the additives are awkward, because they have to be carried out with the door completely open and arranged horizontally, at a level only just above that of the floor.
Secondly, there is the problem of sending the electrical signals generated by the command and programming devices, housed in the door, to the electromechanical members which are housed in the body of the machine, in particular on the back of and under the washing chamber. There is also the need to transfer, from the body of the machine to the door, the feed voltage and the signals generated by sensors housed in the body of the machine.
This requires the use of flexible electrical cables, which are suitably protected and relatively expensive.
To increase the useful volume of the washing chamber, it has been proposed, as described in EP671.143, to arrange at least the detergent measuring and dispensing devices in the upper part of the encasement of the dishwasher, as is usually the case in washing machines.
This is obtained at the expense of a greater vertical size which excludes any possibility of fitting it to be built-in under a work surface..
In a recent patent application from the same Applicant this limitation is avoided foreseeing an original arrangement of the detergent measuring and dispensing devices in the upper side of a counterdoor frame, drawn into recess substantially for the whole of its vertical extension, so as to allow the use of an upper and lower rack with a greater length, partially housed in the recess or, alternatively, an upper auxiliary rack housed in the counterdoor recess.
This solution does not require a greater vertical size of the machine and allows an optimal exploitation of the volume available. It is also particularly ergonomic.
It is a purpose of the present invention to provide a dishwasher machine which gives the same results in an even simpler manner and which is susceptible to improvements to produce further enhancements and advantages, like that of not requiring an electrical connection between loading door and body of the machine.
These results are achieved with a machine realised, in its most simple form, in accordance with claim 1 or 2.
It is a further purpose of the present invention to provide a dishwasher machine in which the advantages outlined above are combined with the further benefit of a substantial cost-effectiveness and flexibility of operation and of a further increase in the useful load volume, obtained in the lower part of the washing chamber.
These further results are obtained with a machine realised according to claim 3.
Substantially, the dishwasher machine according to the present invention is based upon the following considerations and on the design criteria which derive therefrom:

the measuring and dispensing device for prewash and washing detergent, which has the largest size, can be separated from the measuring/dispensing device for liquid rinse aid additives;
in a dishwasher machine, in addition to the interspace between front panel and counterdoor, there are other interspaces in the body of the machine, even though of a lesser thickness, which can be used to house control devices and which are accessible from the front of the machine, if the loading door is open, even only partially;
as well as these interspaces, inside the washing chamber, there are some dead zones, accessible from the loading door, when it is opened, that for constructive requirements or even only for the particular configuration of the crockery, are not actually occupied and used.

Accordingly:

the detergent measuring/dispensing device can be arranged inside the washing chamber, easily accessible when the loading door is open. With this choice it is possible to dispense the detergent, timed in the appropriate step of the wash cycle, by means of water jets and detergent withdrawal activated in the appropriate step and without the need for mechanical or electromechanical devices directly associated with the measurer, so that the structure thereof is extremely simple, reducing itself to a suitably shaped container,
All of the other devices, be they control devices or additive dispensing devices, can be distributed in the interspace between the side (or even upper) walls of the washing chamber and the corresponding outer walls of the encasement, so as not to occupy any useful space in the washing chamber and at the same time to be accessible for activation or for loading, just by opening the door.
the withdrawal of detergent through at least one water jet, activated in the appropriate step, implies the provision of a control member (electrovalve or switch) which intrinsically allows the functionality of the machine to be enriched and in particular decalcified water to be used for certain washing steps and non decalcified water to be used for other steps, like prewash, intermediate cold rinses, and regeneration of the decalcifier.

The characteristics and advantages of the invention shall become clearer from the following description of a preferred embodiment and variants thereof, made with reference to the attached drawings wherein:

figure 1 is a schematic front/rear section view, taken according to the centre line, of a dishwasher machine in accordance with the present invention;
figure 2 is a partial front view, with the door open, of the upper part of the machine of figure 1;
figure 3 is a schematic front/rear section view, taken according to the centre line, of a preferred embodiment of a detergent measuring/dispensing device for the machine of figures 1 and 2, with the detergent draw in loading position;
figure 4 is a section view, according to the view I-I of figure 3, of the measuring device of figure 3;
figure 5 is a schematic front/rear section view, taken according to the centre line, of the device of figure 3, with the detergent draw in work position;
figure 6 is a schematic front/rear section view, taken according to the centre line, of the measuring device of figures 3, 4 and 5 with the detergent draw modified for the use of liquid detergent;
figure 7 is a partial section front view of a preferred embodiment of a measurer/dispenser of rinse aid additives, with the relative reservoir, for the dishwasher machine of figures 1 and 2;
figure 8 is a section view, according to the view II-II of figure 7, of the device of figure 7;
figure 9 is a view from above of the device of figure 7;
figure 10 is the hydraulic diagram of a dishwasher machine known in the prior art;
figure 11 represents a preferred embodiment of hydraulic diagram for the dishwasher machine of figures 1 and 2, with indications with a dashed line of possible variants thereof;
figure 12 is an overall partial section front view of the lower part of a dishwasher machine, according to a preferred embodiment of the invention, which incorporates all of the improvements foreseen and considered in the following description.

With reference to figure 1 the dishwasher machine according to the present invention essentially comprises a washing chamber 1, generally made of stainless steel, housed in an encasement 2 and closed, with a water-tight seal, by a front door 3, hinged to the container in its lower part.
Normally, the encasement and the door are sized so as to be able to be housed built-in under a work surface 4, with the front door 3 masked by a panel 5.
The front loading door consists of a flat front panel 6 and of a stainless steel counterdoor 7, conveniently drawn to form a recess surrounded by a raised frame 8 which engages to form a seal with a gasket 9, mounted near to the edge of the washing chamber.
In dishwashers of the prior art the interspace 10, between front panel and counterdoor, is used to house the control devices which are accessible, in the models foreseen for built-in installation, from the upper edge of the door, when the door is at least partially open. The measuring and dispensing devices for the detergent and the additives are also housed in the interspace. As already stated, the consequence of this is that, unlike that which is illustrated in figure 1, the counterdoor panel can be drawn into recess in just the lower part and not also in the upper part, as illustrated.
In accordance with the present invention the measuring/dispensing device is divided in two distinct components: a detergent measuring/dispensing device, with an extremely simple structure (essentially it involves a sliding drawer, with two compartments in line, housed in a dead zone of the washing chamber and supported by the upper rack with which the dishwasher machine is usually provided) and, separate from this, an additive measurer/dispenser 13, with the relative reservoir 12, housed in the interspace between one of the side walls of the washing chamber and the corresponding outer wall of the dishwasher machine.
Let us consider the two aspects separately. For the identification of the dead zones where the detergent measurer/dispenser drawer is to be arranged it is helpful to refer to figure 2 where, in a front view, a portion of the upper rack 16 is shown which is generally intended, and for this purpose designed, to house a set of dishes 17, arranged vertically one behind the other, suitably distanced.
Completely identical is the structure of the other half of the rack, only partially represented.
Supported from above by the rack, a sprayer 19 is rotatably mounted, with opposing horizontal arms, which receives, in a known manner, through a horizontal manifold 21 (figure 1) the jet of liquid detergent coming out of one or the other of the two nozzles 22A, 22B arranged, as shown in figure 1, on the rear wall of the washing chamber, at a different height, mutually closed and opened, in a known manner, according to the vertical position of the upper rack which, as is known, can be installed by the user, according to requirements, in one or the other of the two vertical positions.
In figures 1 and 2 the rack is represented in the lower installation position.
Alternatively, it is known to feed the sprayer 19 with a single venturi tube manifold 18 (fig. 1), arranged vertically and represented with a broken line, the inlet of which faces a spray nozzle 20, open on the top of the washing chamber.
Still with reference to figure 2 it is clear that at the base of the rack, in its middle section, as a result of the load arrangement, there is a dead zone, only partly used to house the manifold 21, in which it is possible to arrange the detergent measuring/dispensing device 15, above the rotational plane of the rotating sprayer 19 and aligned with the manifold 21 (fig. 1). It is clear that an analogous dead zone 24 is available at the dihedral between the base and the side of the rack 16 and thus also at the opposite dihedral, not shown in the figures.
In particular, unlike the dead zone in the middle section, the dead zone 24 can also comprise the volume of the washing chamber, arranged below the rack, outside and peripheral with respect to the cylindrical volume occupied by the rotor 19 during the course of its rotation.
For a better understanding of the invention figures 3, 4 and 5 represent in detail the structure of a preferred embodiment of a detergent measurer, respectively in a central vertical section view, with the draw in the extracted loading position, in a transversal section view according to view I-I of figure 3 and in a central vertical section view, with the draw in work position.
The measurer consists of a prismatic tubular container 25, equipped on the outside with attachment means (not illustrated), such as U-bolts and the like, at the metallic lattice which forms the rack 16 and which is conveniently shaped to form a sort of housing for the container 25.
In the container 25 is housed, capable of sliding axially, in the direction perpendicular to the front of the dishwasher machine, a draw 26 with two compartments in line, 27, 28, open at the top.
The draw 26, at its inner end, is equipped with an elastic tab 29, with an end stop tooth 30, capable of sliding in a lower slot 31 of the container 25. The tooth 30, interfering with the end of the slot, prevents the complete withdrawal of the draw and defines the maximum opening or load position.
At the same time the elasticity of the tab 29 allows, if desired, the disengagement of the tooth and the complete withdrawal of the draw 26 from the container 25, for the replacement thereof with a draw of a different type, as shall be seen later on.
When the draw is in load position it extends beyond the front 32 of the upper rack and the two compartments 27, 28 are easily accessible for the loading of detergent, in a comfortable position, because it is raised with respect to the plane of the completely open loading door. The accessibility is further eased by the possibility of wholly or partially extracting, from the washing chamber, the upper rack which, as is known, is mounted on sliding guides.
The work position of the draw 26, represented in figure 5, is defined by the interference with a nozzle 33, for spraying and withdrawing detergent, integral with the container 25 and whose end inserts into an opening 34 which is conical and/or has support shoulders, made in the most inner wall 35 of the compartment 28.
When the drawer 26 is in work position, the compartment 28 is entirely closed in the container 25 and it is protected by this against the infiltration of sprays and of liquid. Vice-versa the compartment 27 is at least partially open.
It follows from this that the detergent contained in the compartment 27, or prewash detergent, is sprayed by wash jets, present in the washing chamber, right from the first step of the wash cycle.
The liquid which accumulates in the compartment 27 dissolves the detergent (in granules, powder or tablets) contained in the compartment or mixes with the possible liquid detergent, and overflowing causes its withdrawal.
Advantageously, as illustrated, the drawer 26 is designed for the use of solid detergent and both the compartment 27 and the compartment 28 are equipped with at least one discharge opening 36, 37 respectively, arranged near to the base of the compartments, through which the liquid spray, enriched with detergent, even only partly dissolved, can flow into the washing chamber.
The withdrawal of the detergent contained in the compartment 28 (washing detergent) protected from sprays, is carried out with a flow of liquid sent into the compartment through the nozzle 33 and is only activated in a predetermined (washing) step of the wash cycle and possibly in steps following this one.
For this purpose the nozzle 33 is connected to a manifold 38 (figure 1) arranged parallel to the manifold 21, separated from this and fed independently or else, alternatively, to a manifold 39 (figure 2) which extends up to a side of the washing chamber to receive the spray jet coming out of one of the two nozzles 40, 41, arranged at different heights, on the side of the washing chamber, corresponding to the two different installation positions of the rack and activated simultaneously in a predetermined step of the wash cycle.
Figure 6 represents, in a vertical central section view, a draw designed for the use of liquid detergent which differs from the previous one in that the discharge openings 36, 37 are not included and are replaced by two inverted siphons 38, 39.
The base of the two compartments is slightly raised, to ensure a good draft of the siphons, with an outlet arm which extends beyond the base.
Moreover, a vertical diaphragm 40 separates the compartment 28 from the wall 35 in which there is the opening 34 for coupling with the nozzle 33 and prevents the escape of liquid detergent from the opening 34, whatever the vertical position of said opening.
The operation of this draw is simple: the increase in level of the liquid contained in the compartments, caused by the jet sprays (compartment 27) or by the flow fed through the nozzle 33 (compartment 28) causes the activation of the siphon and consequently the rapid discharge of the detergent in the washing chamber. The draw of fig. 6 can be supplied as an interchangeable element with the draw of figures 3, 4 and 5.
Alternatively it is possible to foresee the draw of figures 3, 4 and 5 with two detachable containers which insert into the compartments 27, 28 and are structurally identical to the compartments of the draw of figure 6.
In this way the draw can be adapted to receive both solid and liquid detergent also in combination, according to whether or not auxiliary containers, also by choice, are present.
Figures 7, 8 and 9 respectively represent, in a front partial section view, in a composite vertical section view, according to the view II-II of figure 7, and in a view from above, a preferred embodiment of a measuring/dispensing device for rinse aid additives, already shown schematically in figures 1 and 2 (where it is specified by reference numerals 12,13), to be housed in the interspace between one side of the washing chamber and the corresponding outer wall of the encasement.
The device essentially comprises a reservoir 41, preferably obtained by the welding of two plastic shells 42, 43 which also form a small discharge chamber 44, in communication with the inside of the reservoir 41 through an opening 45 which can be shut.
The reservoir 41 is equipped with an inlet pipe coupling 46, formed integral with the shell 43 and threaded externally, which inserts into an opening of the side 47 of the washing chamber, upon the insertion of a gasket 48.
A threaded locking ring 49, screwed onto the pipe coupling 46, locks sealed the reservoir 41 against the side 47.
In the pipe coupling 46, equipped with a cylindrical inner seat with suitable inclination with respect to the plane of the side 47 of the washing chamber, is engaged, mobile in rotation, an elbow pipe coupling 50, equipped with a removable closing cap 51 of the screw or bayonet type.
Through the pipe coupling 50, conveniently orientated so as to face towards the front, flush with the front edge 52 of the washing chamber (or even beyond) by passing over the sealing gasket 9 and the relative inner support 53, it is possible to comfortably carry out the loading of the rinse aid additives.
With the loading completed, once the pipe coupling is closed, this can be rotated towards the inside of the washing chamber, in the position indicated with a broken line in figures 7 and 9, so as not to interfere with the loading door and the relative frame when the door is closed.
Advantageously, the inclination of the rotational axis of the pipe coupling 50, relative to the plane of the side 47, ensures that the pipe coupling is arranged flush with the wall of the washing chamber which can be equipped, by drawing, with a suitable recess (54 in figure 9) for at least partially housing the pipe coupling, so that it occupies a minimum volume of the washing chamber and does not interfere with the crockery housed here.
The dispensing of the additive, in the appropriate step of the wash cycle, is ensured by the activation of an electromagnet 55 which opens a pin shutter 56 which, in rest position, closes the opening 45.
In this way a measure of additive which essentially depends upon the opening time is poured into the discharge chamber 44 and through this passes into the washing chamber.
Alternatively, for a more precise measure, the pin shutter device can be replaced in a known manner by a volumetric piston pump.
For the flowing of the additive into the washing chamber the discharge chamber 44 is equipped with a pipe coupling 57 which inserts, upon the insertion onto the pipe coupling of a gasket 58, into an aperture of the wall 47.
A ring nut 59, screwed onto the pipe coupling, ensures the seal between pipe coupling and wall and constitutes a further anchoring of the reservoir to the wall.
To avoid the entrance of liquid, dust or of other objects coming from the washing chamber into the discharge chamber 44, said discharge chamber can conveniently be equipped with a bayonet type cap 60 with a small peripheral port for the discharge of the additives in the washing chamber. In this case, foreseeing the shutting off of this port by the electromagnet 55 when activated, and suitably positioning the opening 45 to avoid the formation of air bubbles, the discharge chamber 44 can carry out the function of volumetric measuring chamber.
In this way, having removed from the loading door the detergent measurers/dispensers and the reservoir for rinse aid additives with the relative measurer/dispenser, it is possible to draw the counterdoor into recess for its entire height, increasing the useful load volume of the washing chamber and providing the possibility of using an upper rack of a greater length and capacity or else an auxiliary rack housed in the upper part of the counterdoor recess.
From this point of view it is possible to free the loading door entirely from any control and programming device.
In modern production techniques the control and programming devices essentially consist of one or two electronic boards which also function as a support for control buttons and visualisation devices, normally of the LED type.
The size of these boards perpendicular to their plane is minimal, so that they can be easily housed in the interspace between a side wall of the washing chamber and the corresponding outer wall of the body of the dishwasher machine, with the edge of the board carrying the control buttons and the visualisation devices flush with the front edge of the washing chamber and capable of being accessed through a convenient opening made on the edge.
This arrangement is represented in figure 2, where the control buttons and the visualisation devices are identified by the reference numeral 61. Alternatively or in conjunction the control devices can be wholly or partly arranged in the interspace between the top of the washing chamber and the corresponding upper wall of the encasement.
In any case, the controls are easily accessible even only with a limited opening of the loading door, as already takes place in machines foreseen for built-in and fold-away installation.
As a marginal detail it is clear that also the safety microswitch, usually mounted in the loading door, can be moved into the body of the machine, so as to free the loading door from any device which requires an electrical supply.
We can now consider a final aspect: whereas in the dishwashers of the prior art the dispensing of the washing detergent generally takes place through the timed opening of a shutter for closing the dispensing device, controlled by an electromagnet in the appropriate step of the wash cycle, the dispensing of the detergent into the machine according to the invention takes place through a timed flow of liquid, sent, through the manifold 38 of figure 1 or 39 of figure 2, into the compartment for containing the washing detergent.
For this purpose it is sufficient to make a small modification of the hydraulic diagram of the dishwasher machine which can be used, according to another aspect of the present invention, to gain further benefits.
For a better understanding of this aspect we refer to figure 10 which is an overall view of the hydraulic diagram of a dishwasher machine of the prior art.
The machine is fed from the water mains 91 through an electrovalve 62. The flow of water passes through an anti-backflow device 63 (which prevents a reverse sucking flow in the case of a drop into depression of the water mains) and is conveyed by tubing 64 to a resin decalcifier 65.
The supply flow, partialised by the anti-backflow device 63, also feeds a container 66 for storing regeneration water, equipped with a discharge 67 for releasing the excess water, opening onto the washing chamber.
The decalcified flow leaving the decalcifier is let into the washing chamber 68, crossing a filter 72 in countercurrent with respect to the circulation flow, considered later on.
In particularly advanced versions the discharge pipe 80, from the decalcifier to the washing chamber, is split into two pipes 80 and 81, respectively controlled by two electrovalves 76, 69 to avoid the washing liquid crossing the filter 72. This is crossed in countercurrent, as shall be seen later on, only by regeneration water of the decalcifier.
A pressure switch, not illustrated, interrupts the flow which fills the washing chamber, closing the electrovalve 62 for a predetermined filling level of the washing chamber.
The washing or rinsing water contained in the chamber passes through a filter 72, is made to circulate by a circulation pump 70 and feeds the spraying rotors (usually two), housed in the washing chamber, one of which is represented in figure 10 and is identified by the reference numeral 71.
At the end of each of the various successive steps of prewashing, cold rinsing, washing and final rinsing, which normally constitute a wash cycle, the washing/rinsing liquid is discharged by a discharge pump 73 and the washing/rinsing water in the chamber is reintegrated to carry out the subsequent step with the opening of the electrovalve 62 and of the electrovalve 69, if present.
The wash cycle is completed by a regeneration step of the decalcifying resin: the hard water contained in the container 66 is discharged, by activating an electrovalve 74, into a reservoir of regeneration salts 75, communicating with the decalcifier 65 and conveyed into the filter 72 with the activation of the electrovalve 76, if present.
At the same time the discharge pump 73 is activated, so that the regeneration water, crossing the filter in countercurrent with respect to the circulation flow, cleans it of the possible residue contained therein.
In this set-up there is the drawback that all of the water used in the various prewashing, washing and rinsing steps is decalcified and this involves a substantial consumption of regeneration salts and of water necessary for the regeneration (indicatively 2-3 litres per cycle).
Not only does this require an appropriate sizing of the container 66 and of the decalcifier 65 (which can be overcome with the execution of many successive regeneration steps during the course of the wash cycle, with the consequent reduction in the capacity of the container 66 and of the decalcifier 65) but also an appropriate sizing of the reservoir 75 for the regeneration salts, to limit the frequency with which the reservoir must be reloaded to within reasonable limits.
This implies that the reservoir 75 be of a substantial size, totally at the expense of the space available for the washing chamber.
On the other hand, it is desirable to carry out the decalcification of just the liquid used in the washing and final hot rinsing steps, which would involve a saving equal to about 60-70% of the regeneration salts (and of the regeneration water) with the consequent possibility of reducing the size of the container 66, of the decalcifier 65 and of the reservoir 75, simplifying and shortening the time of the wash cycle itself (a single regeneration step is sufficient, which is intrinsically shorter).
These results can advantageously be achieved in the dishwasher machine according to the invention, as a direct consequence of the adoption of the measurer/dispenser already described with the withdrawal of detergent carried out by a liquid jet.
Figure 11 represents the hydraulic diagram of the dishwasher machine of the present invention which allows these aims to be realised and at the same time takes care of the withdrawal of the detergent in the appropriate step.
Since the diagram of figure 11 differs from that of figure 10 only in a few details, the functionally equivalent elements are identified with the same reference numerals.
Substantially, the difference consists of the fact that the electrovalve 76 is necessarily present and the decalcified water coming out of the decalcifier 65, instead of being discharged directly into the washing chamber, feeds the compartment 28 for the washing detergent through a pipe 81, the electrovalve 69 and the manifold 38, already shown in figure 1 (or the equivalent manifold 39 of figure 2).
Although many variants are possible (and preferable), this is the only modification necessary.
The operation is therefore the following, keeping in mind that a wash cycle comprises, essentially in order, the cold prewash, cold rinse, hot wash, 1st cold rinse, 2nd hot rinse with drying of the crockery and regeneration steps:
at the start-up the electrovalve 62 is opened but the electrovalves 69,76 remain closed. The hard feeding water fills the container 66, flows out and loads the washing chamber up to the desired level, after which the electrovalve 62 is closed. With the start-up of the pump 70 the circulation flow feeds the rotor 71 and the spray jets withdraw the prewash detergent from the compartment 27, which is exposed to the sprays.
With this step carried out the prewash liquid is discharged by the pump 73.
With a reopening of the electrovalve 62, with valves 69,76 closed, the washing chamber fills directly, with overflow from the container 66 which is already full, and, activating the circulation pump, a cold rinse is carried out with hard water which is then discharged.
To carry out the washing step the electrovalve 62 is again opened and together with this also the electrovalve 69 is made to open.
The decalcified water, before discharging into the chamber, withdraws the detergent from the compartment 28. Then it is heated, made to circulate and finally discharged.
In the subsequent step, the opening of the only electrovalve 62 determines the loading of hard rinsing water coming from the container 66, which is then discharged.
Following the cold rinse there is a hot rinse (with the possible addition of rinse aid additives) carried out with decalcified water, obtained by simultaneously activating the electrovalves 62 and 69.
The passage of liquid, in whole or in part, into the compartment 28, does not involve any drawbacks since the compartment has already been emptied and cleaned from all detergent residue.
With the rinse completed, once the rinsing water is discharged, the electrovalves 74 and 76 are opened jointly and, simultaneously or successively, the discharge pump is activated: the hard water contained in the container 66 passing into the reservoir 75 and into the decalcifier 65, takes care of the regeneration of the resins and at the same time of the washing in countercurrent of the filter 72.
It is clear that many variants can be brought to the described hydraulic diagram.
For example, the feeding of the washing chamber with hard water, instead of coming out of the container 66, can be obtained in a faster manner (the partialisation hole of the anti-backflow device substantially limits the flow rate) with an electrovalve 77, connected to the water mains, which allows entry directly into the washing chamber above the maximum filling level of the washing chamber.
In this case the anti-backflow device is not necessary: it is the washing chamber which carries out this function.
Moreover, the electrovalve 69 becomes superfluous.
Alternatively, it is also possible to foresee, replacing the electrovalve 77, a switch valve 78, arranged on the pipe 64, which sends the hard water to the decalcifier or directly into the washing chamber. The same function of the switch valve can be carried out by two distinct electrovalves, commanded to open alternately.
It is clear that in all of the cases described the regeneration of the resins can be carried out at the end of every step of the cycle which uses decalcified water, with the advantage that the capacity of the container 66 and the size of the decalcifier can be reduced.
In all cases it can be noted that a route for the supply of water into the washing chamber which passes through the decalcifier 65 and the compartment 28 and a further by-pass route which supplies the hard water directly into the washing chamber, without passing through the decalcifier and the compartment 28, are foreseen.
It is then clear that many other variants can be brought: for example, to increase the useful volume of the washing chamber, extending it below, the reservoir 75 for the regeneration salts can be at least partly housed in the interspace between the side wall of the washing chamber, opposite the one which the additive measurer/dispenser faces, and the corresponding outer wall. The reservoir for the regeneration salts can be equipped with a loading pipe coupling which is similar or identical to that of the reservoir for the additives.
Figure 12 schematically represents a front partial section view of the body of a dishwasher machine which advantageously incorporates all of the aspects indicated above.
The measuring/dispensing device 15 is arranged in the washing chamber and is supported by the upper rack 16, so as to be easily accessible.
The reservoir 12 for the rinse aid additives, with the relative measurer, is housed in the interspace between a side of the washing chamber and the corresponding outer wall of the encasement.
The loading pipe coupling 50 of the reservoir 12 opens on one side of the washing chamber, in an easily accessible position.
The reservoir 75 for containing the regeneration salts, already having a per se reduced size, together with that of the decalcifier 65, for the selective use of decalcified water and the consequent reduction in the decalcification and regeneration operations, is equipped with a pipe 85, which constitutes an upward extension thereof with the consequent increase in the volumetric capacity, housed in the interspace between the other side of the washing chamber (opposite the one in which the pipe coupling 50 opens) and the corresponding outer wall.
The pipe 85 opens into the washing chamber with a loading pipe coupling 86, similar to the pipe coupling 50 and easily accessible from the front of the machine, with the loading door open.
The pipe 85 itself, to a large extent, constitutes a container of regeneration salts which allows a reduction in the size of the reservoir 75, arranged below the washing chamber and, unlike that which is foreseen in the prior art, without a loading pipe coupling arranged on the base of the washing chamber, which involves, as is known, a certain vertical size and a constructive limitation, since it must not interfere with the lower rotor.
The smaller size of the reservoir 75 and the absence of a loading pipe coupling on the base of the washing chamber allow the base of the washing chamber, as well as the lower spraying rotor 82, the protective filter grill 83, the heating resistance 84 and the lower rack 87 to be lowered to the great advantage of the useful volume of the washing chamber.
In this way a combined effect is realised:
the loading door, removed of any detergent dispensing device or additive reservoir, can be equipped with a counterdoor drawn into recess for its entire height, with a frontal increase in the useful volume of the washing chamber.
The base of the washing chamber can be lowered with an increase in the useful volume of the washing chamber in its lower part.
Then from the ergonomic point of view, the different devices which require a manual intervention (detergent dispenser, additive reservoir, regeneration salts reservoir) are more easily accessible, since they are equipped with loading openings arranged substantially half way up (40-50 cm from the floor) the body of the machine, unlike that which takes place in the dishwasher machines of the prior art.

Claims

Domestic dishwasher machine, wherein a washing chamber (1), closed at the front by a loading door (3), capable of being opened and hinged at the bottom, houses an upper rack (16), characterised in that it comprises:

a detergent measurer/dispenser device (15) supported by said upper rack (16) and comprising a container (25) with a draw (26), housed in said container and capable of being opened for the loading of detergent, said draw having at least one compartment (28) for containing detergent, protected from sprays when the draw is closed,

water feeding means (62,65,81,38,39) for sending a flow of liquid for withdrawing the detergent in said compartment, during the course of at least one predetermined step of the wash cycle, and

an additive measuring/dispensing device (12,13) housed in the interspace between one side of said washing chamber and a corresponding outer wall, said loading door comprising a counterdoor (7) drawn to form a recess, surrounded by a frame and substantially extending for the whole height of the counterdoor.
Dishwasher machine according to claim 1 wherein the control and programming devices (61) of said machine are housed in the interspace between at least one wall of said washing chamber and a corresponding outer wall, and are accessible on a front edge of said washing chamber, said loading door (3) being free of any electrical connections.
Dishwasher machine according to claim 1 or 2 wherein said water feeding means comprises a decalcifier (65) for sending a decalcified water flow into said compartment (28) and by-pass means (67,77,78) of said decalcifier, to directly convey a hard water flow into said washing chamber, without passing through said detergent containing compartment (28).
Machine according to any of the previous claims, wherein said draw (26) comprises a second detergent containing compartment exposed to the sprays in said washing chamber.
Machine according to any of the previous claims, wherein said additive measuring/dispensing device (12,13) comprises a reservoir (41) equipped with a loading pipe coupling (50), exposed in said washing chamber and directable to take up a loading position and a position taking up a minimum amount of space in said washing chamber.