EP2344016B1

EP2344016B1 - Method and device for conveying washing agents into a tub of a washing machine

Info

Publication number: EP2344016B1
Application number: EP09736285.9A
Authority: EP
Inventors: Costantino Mariotti; Giovanni Bombarideri; Daniele Rossi
Original assignee: Indesit Co SpA
Current assignee: Whirlpool EMEA SpA
Priority date: 2008-09-04
Filing date: 2009-08-28
Publication date: 2016-06-15
Anticipated expiration: 2029-08-28
Also published as: ITTO20080655A1; RU2497435C2; WO2010026516A1; RU2011112809A; IT1391855B1; EP2344016A1

Description

The present invention relates to a method for conveying washing agents into a tub of a washing machine according to the preamble of the first claim.
The present invention also relates to a washing machine equipped with a device for conveying washing agents into a tub according to the preamble of claim 5.
Reference will be made herein to washing machines, such as laundry washing or washing/drying machines or the like, which are equipped with a rotary drum housed in a tub and containing laundry to be washed.
Such machines are connected to a water main pipe delivering clean water which enters the machine through a supply duct; clean water is normally also used for carrying two washing agents, e.g. detergent and softener, into the tub.
For this purpose, the machine is equipped with two separate containers adapted to be flushed by the incoming clean water flow, the latter crossing them and carrying with it the washing agent contained therein towards the tub; such containers are typically separate compartments of a filling drawer.
With this system, the supply duct connected to the water main is split in two delivery ducts, each afferent to a respective container or drawer compartment and fitted with a valve allowing it to be individually opened or closed, so that two washing agents can be dispensed independently.
With the passing of time, designers have felt the need to be able to dispense three different washing agents, or to dispense washing agents at three different times during the operating cycle of the machine (e.g. a first detergent or dye fixative, a second detergent and a softener); this requires three separate containers, each adapted to contain a respective washing agent.
To this end, a third additional compartment operating in the same manner as the other two has been added to the drawer; it has therefore been necessary to ensure that said third compartment is supplied as well by using a third delivery duct which involves an additional cost, especially because it too must be equipped with a dedicated valve.
In order to simplify the construction of the machine and limit the production cost thereof, supply devices having two inlets and three outlets, known as "cross-jet" devices, have been conceived, like the one described in patent GB 2353540 to AWECO Appliance System GmbH & CO. KG; in these devices, the three outlets can be supplied alternately depending on how the two inlets are being supplied.
A known cross-jet device 1 is also shown in the annexed Fig. 1: said device 1 receives water from the main through supply duct 7 that branches off into two delivery ducts 2, 3, ending at respective inlets consisting of delivery mouths A, B; it should be noted that each delivery duct 2,3 is provided with a dedicated valve or solenoid valve 22, 23, so that it can be opened or closed.
Cross-jet device 1 comprises a crossing chamber X to which the two delivery mouths A, B and three drain mouths C, D, E are afferent; the latter are connected to as many drain ducts 4, 5, 6 in fluid communication with the three drawer compartments; two drain mouths C, D are aligned with two delivery mouths A, B in a manner such that the lines connecting each delivery mouth to the respective drain mouth intersect within chamber X; the third drain mouth E is located between the other two, and all mouths A, B, C, D, E substantially lie in the same horizontal plane.
Crossing chamber X contains air, and the principle of operation of device 1 is based on the crossing of the water jets emitted by delivery mouths A, B: when a jet of water comes out of either inlet A or inlet B, the jet will cross crossing chamber X in a straight line and reach respective outlet C or D; this condition is shown in Fig. 1 by the solid arrows.
On the contrary, when water comes out of both inlets A and B, the two corresponding water jets will cross each other within chamber X, resulting in a jet directed towards the third mouth E; this condition is shown in Fig. 1 by the dashed arrows.
There is thus no need to use a third delivery duct with a respective solenoid valve, since the three outlets can be supplied alternately by supplying the first inlet A, the second inlet B or both inlets A and B.
Additional improvements are described in the aforementioned patent GB 2353540 , to which reference should be made for further explanations.
Although this solution simplifies the construction of the washing machine, it is still relatively complex and requires that the supply duct be split in two delivery ducts, each of which must be fitted with a dedicated solenoid valve.
It is a first object of the present invention to further simplify the above solution by providing a lower-cost, simpler-construction washing machine.
It is another object of the present invention to reduce the number of components required for the operation of a cross-jet supply device like the one described above.
Said object is achieved through a washing machine implementing the method according to the first claim appended hereto.
A further object of the present invention is to provide a washing machine according to the appended claim 5.
Further advantageous aspects or variants are also specified in the appended claims, which are intended as an integral part of the present description.
The present invention is based upon the idea of using the circuit for recirculating the wash liquid contained in the tub (which may be either pure water or water mixed with a washing agent, according to the case) also for supplying one of the two inlet mouths of the cross-jet supply device.
In order to reduce clean water consumption, washing machines are often equipped with recirculation circuits, like the ones described in patents DE 43 37 943 or DE 199 02 911 , both in the name of MIELE & CIE GmbH, and US 5,191,669 in the name of

WHIRLPOOL CORPORATION.

In these machines, the wash liquid contained in the tub is drawn, possibly filtered and then delivered again into the tub, e.g. by spraying it onto the laundry, without needing any additional clean water supply.
To this end, known machines are equipped with a pump adapted to circulate the wash liquid in the recirculation circuit; typically, the latter includes the pipes to and from the tub, and possibly also valves or switches and cleaning filters.
By delivering at least a portion of the wash liquid contained in the tub to the cross-jet supply device, the machine can be simplified, as will be further explained below, by eliminating all that part of the hydraulic circuit which is used for splitting the supply duct in two delivery ducts connected to the cross-jet device; this is beneficial in terms of reduction of the number of components and simplification of the hydraulic circuit.
These features as well as further advantages of the present invention will become apparent from the following description of an embodiment thereof as shown in the annexed drawings, which are supplied by way of non-limiting example, wherein:

Fig. 1 is a schematic view of a cross-jet supply device and a respective hydraulic circuit according to the prior art;
Fig. 2 is a schematic view of a cross-jet supply device and a respective hydraulic circuit according to the present invention;
Fig. 3 shows a first variant of Fig. 2;
Fig. 4 shows a second variant of Fig. 2;
Fig. 5 is a schematic view of a washing machine comprising the device and circuit of Fig. 2.

The inherent operation of cross-jet supply device 1 shown in Fig. 1 is per se known and has already been described above, so that it needs no further explanation.
Referring now to Figs. 2 and 5, there is shown a cross-jet supply device 1 with the respective hydraulic circuit in accordance with the teachings of the present invention.
Said Figs. 2 and 5 illustrate a simple and low-cost solution of said circuit through a general diagram (Fig. 2) and a schematic view of the arrangement of said circuit in washing machine 100 (Fig. 5), i.e. a laundry washing or washing/drying machine.
In this case, cross-jet supply device 1 is arranged immediately on top of washing agent drawer 40, and has three outlets consisting of three drain mouths C, D and E in fluid communication (through drain ducts 4, 5, 6) with as many distinct compartments 43, 41, 42 of drawer 40; the first and second inlets consist of the two delivery ducts A and B.
Compartments 41, 42, 43 are in turn in fluid communication with tub 101 through a supply hopper 103 (per se known); the washing or washing/drying machine 100 normally also comprises a rotary drum 102 housed in the tub, in which the laundry is placed.
Three compartments 41, 42, 43 of drawer 40 can be filled with three distinct washing agents (e.g. a dye fixative, a detergent and a softener), or more in general with any washing agents (even all of the same type) adapted to be dispensed into the tub at different times of the wash cycle (e.g. two detergents, whether the same or different, and a softener or the like).
Figs. 2 and 5 also show pump 10, which is in fluid communication with tub 101 through suction duct 11; the outlet of said pump 10 is connected to delivery duct 3 ending in crossing chamber X of device 1, with second mouth B aligned with drain mouth D.
When the machine is equipped with a recirculation circuit, pump 10 and suction duct 11 advantageously consist of the recirculation pump and recirculation duct, respectively, of the washing machine.
Supply duct 7, intercepted by valve 22, is the second delivery duct 2 ending in crossing chamber X with first mouth A aligned with drain mouth C; third drain mouth E is visible between drain mouths C and D aligned with the respective delivery mouths A and B.
The system operates as follows: initially, tub 101 is filled (this normally takes place during a "prewash" or "water supply" step, when the laundry is imbibed): to this end, valve 22 opens and clean water (supplied by supply duct 7 connected to the water main) flows in delivery duct 2 and reaches delivery mouth A; the water jet coming out of delivery mouth A crosses chamber X in a straight line and reaches drain mouth C, which is in fluid communication with the tub through drain duct 4, compartment 43 and hopper 103.
If there are any washing agents in drawer 43, they will be already swept along by the clean water flow during this initial step.
When a certain quantity of wash liquid (which may be either pure water or water mixed with washing agents) is present in tub 101, it is conceivable to use pump 10 in order to dispense a washing agent contained in compartment 42 or in compartment 41.
In such a case, if a washing agent contained in compartment 41 is to be dispensed, pump 10 is turned on and valve 22 is kept in the condition in which it closes supply duct 7: the wash liquid taken from the tub through suction duct 11 thus flows in delivery duct 3 and comes out of mouth B in the form of a jet that crosses, unintercepted, chamber X, thus reaching mouth D and then compartment 41, from where it carries along any washing agents contained therein towards the tub.
When a washing agent contained in compartment 42 is to be dispensed, pump 10 is turned on and solenoid valve 22 is opened as well: thus, the wash liquid taken from the tub flows in delivery duct 3 and comes out of mouth B in the form of a jet that hits the clean water jet coming out of mouth A, thereby forming one common jet directed towards central mouth E, which is in fluid communication with compartment 42, thus allowing the washing agents contained therein to be dispensed into the tub.
In this regards, it should be pointed out that compartments 41 and 42 must necessarily be intended for washing agents to be used in operating steps of the machine to be executed after the tub filling step; for instance, compartments 41 and 42 are intended for a detergent and/or a softener, whereas compartment 43 may be used for a dye fixative or a detergent to be dispensed during the prewash step; advantageously, compartment 41 is assigned to detergent and compartment 42 is assigned to softener.
According to this teaching, the wash liquid recirculation circuit to and from tub 101 also comprises device 1 and drawer 40; during the recirculation step of the machine, the wash liquid taken from the tub flows through both device 1 and drawer 40; more in detail, two types of recirculation are possible: mixed recirculation, where clean water is also used, and unmixed recirculation.
In mixed recirculation mode, valve 22 is open and pump 10 is on: in this case, the flow of wash liquid taken from the tub is added to the flow of clean water supplied from the water main, and then this combined flow reaches the tub through compartment 42; this mode of operation may be used when the quantity of wash liquid in the tub is insufficient for the subsequent wash steps to be carried out by machine 100; the wash liquid recirculation circuit to/from tub 101 includes in this case suction duct 11, pump 10, delivery duct 3, delivery mouth B, chamber X, outlet mouth E, drain duct 5, compartment 42, and hopper 103.
In unmixed recirculation mode, valve 22 is closed and pump 10 is on: in this case, the flow of wash liquid taken from the tub is wholly re-admitted into the tub (except for any liquid spilled or partialized by any means) through compartment 41; this mode of operation may be used when the quantity of wash liquid in the tub is sufficient for the subsequent wash steps to be carried out by machine 100; the wash liquid recirculation circuit to/from tub 101 includes in this case suction duct 11, pump 10, delivery duct 3, delivery mouth B, chamber X, outlet mouth D, drain duct 6, compartment 41, and hopper 103.
Pump 10 may be a normal recirculation pump, per se known, which will not be discussed any further.
Incidentally, it should be pointed out that a positive displacement pump will also stop the water flow when it is off, thus acting upon duct 11 just like a closed valve.
By following the teachings of the present invention it is possible to simplify the machine and reduce the number components thereof, since any one of the three outlets C, D, E can be supplied alternately as a function of the two inlets A, B, one of which is supplied with wash liquid from the tub of the washing machine and the other is supplied with clean water from the main.
In this manner, the three compartments 41, 42, 43 of drawer 40 can be fed by using a minimal number of machine parts or components.
Of course, this basic idea may be subject to many variations: one of such variations is shown by way of example in Fig. 3: here, the recirculation step can also be performed without necessarily involving drawer 40 (as was the case in Fig. 2); in this drawing, equivalent parts are designated by the same reference numerals and will not be described any further.
Pump 10' has two outlets which can be supplied as a function of the direction of rotation of the electric motor of the pump itself; pumps of this type are per se known and have been described, for example, in patent US 6,617,733 in the name of DAEWOO ELECTRONICS CO., LTD.
In short, pump 10' is a dynamic impeller-type pump; depending on the direction of rotation of the electric motor that drives the impeller, the wash liquid coming in from suction duct 11 will be alternately delivered into either one of ducts 3 and 13.
With particular reference to Fig. 3, by using this type of pump 10' it is possible to route the wash liquid taken from tub 101 through suction duct 11 alternately to delivery duct 3 afferent to device 1 or to return duct 13, which is directed, for example, to nozzles adapted to spray the wash liquid onto the laundry.
It should be specified that the above-described pump 10' may be replaced with a different pump, e.g. a pump fitted with a flow diverter or a shutter adapted to partialize the output flow in order to direct a portion thereof into duct 3 and the other portion into duct 13.
Return duct 13 may also include a drain branch which can be opened by means of a dedicated valve (not shown).
This variant operates in much the same manner as the example previously described with reference to Fig. 2, and will not therefore be described in detail; let it suffice to say that in this case the washing agent contained in compartment 41 or 42 can be dispensed independently of recirculation, unlike the preceding case, where during the first recirculation step the washing agent contained in compartment 41 or 42 (depending on whether solenoid valve 21 is open or closed) is necessarily dispensed; it follows that, if on the one hand this solution implies the presence of a return duct 13 specifically intended for recirculation, on the other hand it offers more flexibility of use.
The different recirculation modes (mixed or unmixed) are similar to those discussed above, with the additional option of executing an unmixed recirculation step and a mixed recirculation step without necessarily involving drawer 40 (or any compartment thereof): in unmixed recirculation mode, it will be sufficient to activate pump 10 in a manner such that it directs the wash liquid into duct 13 while keeping valve 22 closed, whereas in mixed recirculation mode it will be sufficient to activate pump 10 in a manner such that it directs the wash liquid into duct 13 while keeping valve 22 open (in this second case, mixing takes place in tub 101).
A further variant is illustrated in Fig. 4 by using the same reference numerals for equivalent parts.
This variant is conceptually similar to that of Fig. 3, with the difference that in this case pump 10 is a traditional one (with one inlet and one outlet); at the delivery side of pump 10 there is a flow diverter 14 adapted to convey the wash liquid alternately into return duct 13 or into delivery duct 3: in practice, pump 10 and flow diverter 14 carry out the same functions as pump 10', and may even be integrated into a single casing.
In this case as well, the system operation is similar to that described above with reference to Fig. 3 and will not therefore be discussed any further, except that flow diverter 14 can also partialize the wash liquid flow so that device 1 and return duct 13 receive flows which can be adjusted at will by operating diverter 14; such a solution may be advantageous when the jets simultaneously emitted by mouths A and B are not capable of generating a single jet directed towards mouth E (e.g. because the flow rates of the jets coming out of mouths A and B are different, and the resulting jet is not directed towards mouth E), in which case flow diverter 14 also acts as an element for adjusting and calibrating device 1, thus allowing to change the rate of the wash liquid flowing in one of the two inlets of device 1 for the purpose of obtaining an optimal operation of device 1.
Furthermore, this allows to obtain a hybrid operation, wherein a portion of the wash liquid taken from the tub is delivered back into it through return duct 13 and the other portion is directed to dispenser 1, and from there to compartment 41 or 42 (depending on whether solenoid valve 21 is open or not).
It is also conceivable to connect return duct 13 to a drain.
Further advantages are offered by this variant by allowing to use a traditional pump 10, which is less expensive and delicate compared to double-outlet pump 10', and by diverting the output jet by means of a simple, robust and inexpensive flow diverter 14.
The solutions illustrated above have clearly shown that, unlike the prior art, supply duct 7 is not split in two, since it is only afferent to delivery duct 2, and that solenoid valve 22 of Fig. 1 is absent, which leads to the advantage of a simpler circuit having a smaller number of components.
On the basis of the teachings provided herein, many further variations and changes are of course conceivable, all of which will still fall within the scope of the present invention.
For example, pump 10 (or 10') may be (in certain solutions) a pump used for both the recirculation and drain functions (to a drain duct), being provided for that purpose with a flow diverter arranged downstream of the pump itself and adapted to switch the path of the wash liquid taken from the tub towards a drain or towards a recirculation circuit; in other solutions, the pump used for the drain function may alternatively be distinct from the one used for the recirculation function.
As a further alternative, flow diverter 14 may be a three-way valve.
The valves may advantageously consist of solenoid valves, which can be controlled automatically.
Of course, as an alternative to drawer 4, compartments 41, 42, 43 for the three washing agents may more generally be three separate washing agent containers associated with or incorporated into other devices of the washing machine; for example, they may be integrated into the machine frame, arranged in a fixed position and filled from above, or else they may be containers internally or externally associated with the tub, e.g. arranged on the door that allows access to the tub and drum.
In all of these cases, the three containers will be supplied by means of device 1 as previously described, being additionally necessary only to ensure that the three drain ducts 4, 5, 6 are afferent to the respective containers in fluid communication with tub 101.
The arrangement of cross-jet device 1 on top of drawer 4 is optional, since device 1 may also be installed in a remote position, at a distance from the drawer or containers.
As a further variant, four or more containers may of course be used and supplied alternately depending on the water flow carried by duct 3: in the above-described cross-jet device, in fact, the two input flows generate an output flow directed towards that outlet which is not aligned with the two inlets.
If the two liquid flows in ducts 2 and 3 are different, the resulting jet may not be directed in the middle, but at a variable angle dependent on the flow rate difference between the two jets, so that it may even supply a fourth outlet (not shown) afferent to a fourth container.
This reasoning may be extended to any number of outlets, provided that the flow rate can be adjusted with accuracy.
In this respect, the flow rate may be adjusted by acting upon the pump, e.g. by increasing the revolution speed thereof, if it is a dynamic impeller-type pump, or else through flow diverter 14 as previously described.
By adjusting the flow rate it will thus be possible to supply any one of the available outlets.

Claims

Method for alternately supplying one of at least three outlets (C,D,E) of a cross-jet device (1) delivering a liquid to at least three washing agent containers (41,42,43) in a washing machine (100), in particular a laundry washing or washing/drying machine, wherein said at least three containers (41,42,43) are in fluid communication with a tub of the washing machine (100), and wherein the cross-jet device (1) comprises a crossing chamber (X) to which a first and a second inlet (A,B) and at least three outlets (C,D,E) are afferent, which outlets (C,D,E) are in fluid communication with said at least three containers (43,41,42) and can be supplied alternately with said liquid depending on whether one or both of the inlets (A,B) are being supplied, and wherein the liquid supplied to the first inlet (A) is clean water taken from the water main,
characterized in that
the liquid supplied to the second inlet (B) is a wash liquid taken from the tub.
Method according to claim 1, comprising the steps of:
- drawing said wash liquid from the tub

- delivering said wash liquid to the second inlet (B) of said cross-jet device (1)

- preventing clean water from being supplied to the first inlet (A) of said cross-jet device (1)
in order to generate a jet of said wash liquid that reaches, unintercepted, a first one of said outlets (D) and then flows to a first washing agent container (41), thus conveying a washing agent contained in said first container (41) into the tub (101).
Method according to claim 1, comprising the steps of:
- drawing said wash liquid from the tub

- delivering said wash liquid to the second inlet (B) of said cross-jet device (1)

- supplying said clean water to the first inlet (A) of said cross-jet device (1) so as to generate a jet of said wash liquid and a jet of said clean water mutually interfering in the crossing chamber (X) to form a single jet directed to a third one of said outlets (E), which then flows to a respective washing agent container (42), thus conveying a washing agent contained in said container (42) into the tub (101).
Method according to any of the preceding claims, comprising a step of partializing the flow of said wash liquid before delivering it to said inlet (B).
Washing machine (100), in particular a laundry washing or washing/drying machine, of the type comprising a tub (101) that houses a rotatable drum (102), wherein the tub (101) is in fluid communication with at least three washing agent containers (41,42,43), and additionally comprising a cross-jet device (1) for supplying a liquid to said at least three containers (41,42,43), wherein the cross-jet device (1) comprises a crossing chamber (X) to which a first and a second inlet (A,B) and at least three outlets (C,D,E) are afferent, which outlets (C,D,E) are in fluid communication with said at least three containers (43,41,42) and can be alternately supplied with said liquid depending on whether one or both of the inlets (A,B) are being supplied, wherein the first inlet (A) of the cross-jet device (1) is in fluid communication with a water main
characterized in that
the second inlet (B) of the cross-jet device (1) is in fluid communication with the tub (101) such that the liquid supplied to the second inlet (B) is a wash liquid taken from the tub.
Washing machine (100) according to claim 5, comprising a pump (10,10') in fluid communication with the tub (101) through a suction duct (11), said pump (10,10') being in fluid communication with the second inlet (B) of said cross-jet device (1).
Washing machine (100) according to claim 4 or 5, comprising a supply duct (7) in fluid communication with a water main and with said first inlet (A), wherein the cross-section of said supply duct (7) can be shut off by a valve (22).
Washing machine (100) according to one or more of claims 5 to 7, wherein the pump (10') is a double-outlet dynamic pump, also comprising a return duct (13) in fluid communication with the double-outlet dynamic pump (10') and with said tub (101).
Washing machine (100) according to one or more of claims 5 to 7, wherein a flow diverter (14) is mounted downstream of the pump (10) and also comprises a return duct (13) in fluid communication with said tub (101), and wherein the flow diverter (14) is in fluid communication with at least the pump (10), the second inlet (B) and the return duct (13).
Washing machine (100) according to one or more of claims 5 to 9, wherein the cross-jet supply device (1) is located on top of a drawer (40) for loading washing agents, and wherein the three containers are three distinct compartments of said drawer (40).