(19)
(11) EP 0 519 875 B1

(12) EUROPEAN PATENT SPECIFICATION

(45) Mention of the grant of the patent:
12.07.1995 Bulletin 1995/28

(21) Application number: 92830245.4

(22) Date of filing: 22.05.1992
(51) International Patent Classification (IPC)6D06F 39/08

(54)

Hydraulic circuit for supplying water and detersive to a washing machine

Hydraulischer Kreislauf zum Zuführen von Wasser und Waschmittel in eine Waschmaschine

Circuit hydraulique pour alimenter une machine à laver en eau et en détergent


(84) Designated Contracting States:
DE FR GB IT

(30) Priority: 12.06.1991 IT MI910525 U

(43) Date of publication of application:
23.12.1992 Bulletin 1992/52

(73) Proprietor: CANDY S.p.A.
I-20047 Brugherio (Milano) (IT)

(72) Inventor:
  • Fumagalli, Silvano, c/o Candy S.p.A.
    I-20047 Brugherio (Milano) (IT)

(74) Representative: Cicogna, Franco 
Ufficio Internazionale Brevetti Dott.Prof. Franco Cicogna Via Visconti di Modrone, 14/A
20122 Milano
20122 Milano (IT)


(56) References cited: : 
FR-A- 1 204 775
FR-A- 2 477 591
   
       
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description


    [0001] The present invention relates to a hydraulic circuit for supplying water and a detersive or cleancing agent to a washing machine.

    [0002] As is known, a very important problem of a washing machine, is that related to the so-called "detersive mechanical loss" that is to the amount of detersive that, at the start of the washing cycle, because of the falling of a portion of the detersive into the region downstream of the washing machine basin, is not actually used or exploited.

    [0003] In order to overcome this problem there are at present used several systems; of these systems there is mentioned the basin preloading system, in which the basin and the portion underlying it are partially filled with water before supplying the detersive from its vessel to the basin, in order to prevent the detersive from being entrained by the first discharging water.

    [0004] Even if this system has been found to be partially effective, it however presents the problem that,since there are at present used continuously decreasing water amounts, a differentiated water discharging will provide a continuously decreasing water amount for entraining the detersive dose.

    [0005] In particular, as the so-called compact detersives are used, a poor fluidity problem can occur.

    [0006] In order to perform the above mentioned operation, it is necessary to preset the control device of the washing machine to a mechanical type of operation, which will cause the cost of the control device to increase.

    [0007] Another prior system provides for the use of either a ball or disc valve to be directly arranged in the discharging hole of the basin.

    [0008] With such a valve, the pushing force on the valve closure is provided by the remaining water column which is held in a suitable vessel.

    [0009] The main drawbacks of this system are a not perfect closure of the valve, mainly because of loose bodies such as buttons, threads and the like, and a difficult opening of the valve itself, in the case of a discharging or draining circuit partially obstructed.

    [0010] Thus, such a system, which is comparatively expensive, is used for high quality washing machines.

    [0011] The document FR-A- 2 477 591 discloses a hydraulic circuit having substantially the features of the pre-characterizing portion of the main claim.

    SUMMARY OF THE INVENTION



    [0012] Accordingly, the aim of the present invention is to overcome the above mentioned drawbacks, by providing a new hydraulic circuit for supplying water and a detersive or cleancing agent to a washing machine which allows to greatly reduce the detersive mechanical losses.

    [0013] Within the scope of the above mentioned aim, a main object of the present invention is to provide such a hydraulic circuit for washing machines which allows to efficiently exploit the available water amount in order to efficiently entrain the detersive from the vessel thereof to the washing machine basin without the need of constructionally modifying the main components of the washing machine.

    [0014] Yet another object of the present invention is to provide such a hydraulic circuit which is so designed as to provide a water turbulence or flow suitable to prevent the fitting ducts from being obstructed.

    [0015] Yet another object of the present invention is to provide such a hydraulic circuit for washing machines which is very reliable in operation and which, in addition,can easily be made starting from easily available elements and materials and which, moreover, is very competitive from a mere economic standpoint.

    [0016] According to one aspect of the present invention, the above mentioned aim and objects, as well as yet other objects, which will become more apparent hereinafter, are achieved by a hydraulic circuit for supplying water and a detersive to a washing machine, having the features of the characterizing portion of the main claim.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0017] Further characteristics and advantages of the present invention will become more apparent from the following detailed description of a preferred, though not exclusive, embodiment thereof, which is illustrated, by way of an indicative, but not limitative, example in the figures of the accompanying drawings, where:

    Figure 1 is a front view of the hydraulic circuit according to the present invention;

    Figure 2 is a side view of the subject hydraulic circuit;
    and

    Figures 3 and 4 illustrate two possible embodiments of the first fitting duct included in the hydraulic system according to the invention.


    DESCRIPTION OF THE PREFERRED EMBODIMENT



    [0018] With reference to the figures of the accompanying drawings, the hydraulic circuit for supplying water and detersive to a washing machine, which has been generally indicated at the reference number 1, comprises a first fitting duct 2 which is connected to the bottom portion of a manifold element 3 arranged under the vessel 4 provided for receiving the detersive or cleansing agent.

    [0019] The first duct 2 extends downwardly, to a collecting region which is arranged at the lowermost point of the hydraulic circuit.

    [0020] This collection region comprises the body 5 of the draining or discharging pump which, advantageously, is of a self-cleaning type.

    [0021] From tests performed by the Applicant it has been found that, in order to prevent the detersive from accumulating, it is necessary to arrange the mouth portion 6 connecting the first fitting 2 to the body 5 with a slanted arrangement with respect to a horizontal line of about 30°: in fact, with such a slanted arrangement, the detersive is effectively prevented from accumulating in the duct.

    [0022] In fact, if the mouth portion 6 would be arranged vertically, because of a narrowing of the liquid flow during the water loading step, the detersive would accumulate on the side walls which thing, on the contrary, does not occur if the fitting duct forms a loop arrangement at sail mouth portion so as to facilitate the outflow of the water on the walls.

    [0023] In order to prevent the detersive from accumulating, the first fitting duct, as is shown in figure 3,has an elliptical inner configuration, indicated at the reference number 10, which is directly obtained during the molding of the duct or, if desired, and as is shown in figure 4, the duct 1 has a smooth inside, and a coil or helical element 11 is added to it, so as to provide a turbulence effect in the duct effective to efficiently spread the detersive through the water, by breaking possible large size particles susceptible to be present in a commercially available detersive material.

    [0024] Thus, the supplied water, by flowing about the mentioned coil element, will dissolve the mentioned comparatively large size detersive particles or agglomerates.

    [0025] As shown, from the body 5 there extends a second fitting duct, indicated at the reference number 20, which leads to the bottom of the basin 21.

    [0026] In this manner, the first loaded water will remove the detersive from the vessel 4 and will entrain it to the body 5, which constitutes the lowermost point of the hydraulic circuit, and then will cause the detersive to be raised to the basin owing to the pushing effect of the remaining water and because of the pressure column of the circuit.

    [0027] The hydraulic circuit further comprises a draining syphon duct 30.

    [0028] In this connection it should be pointed out that the disclosed circuit is of a fully static type, since the fitting duct, which is not connected to the basin, will prevent any wear due to a vibration of the basin assembly.

    [0029] It is moreover to be pointed out that the distance of the syphon bent portion of the draining duct is a comparatively great one, since it does not allow the detersive solution to enter the draining duct if the water has not reached a set level in the basin, at which the solution will be sufficiently diluted.

    [0030] From the above disclosure it should be apparent that the invention fully achieves the intended aim and objects.

    [0031] In particular, the fact is to be pointed out that, owing to the invention, it is possible to exploit the full amount of the water present in the basin in order to drive the detersive and solution from the detersive vessel to said basin, without the need of modifying the main construction of the washing machine.

    [0032] Moreover, a static type of hydraulic circuit is provided which is not affected by the swinging or vibrating movements of the washing machine basin.


    Claims

    1. A hydraulic circuit for supplying water and a detersive to a washing machine, said hydraulic circuit comprising a first fitting duct (2) extending between a manifold element (3) of said washing machine under the detersive loading vessel (4) and a collection region (5) arranged at the lowermost point of the hydraulic circuit, there being moreover provided a second fitting duct (20) extending between said collection region (5) and the bottom of the basin (21) of the washing machine, said collection region comprising the body (5) of a draining pump, characterized in that said first fitting duct (2) is connected to said body by means of a mouth portion which is slanted at 30° with respect to a horizontal line and that said first fitting duct has its cross-section provided with a helical arrangement (10,11) adapted to provide a turbulence effect in the duct effective to efficiently spread the detersive through said water.
     
    2. A hydraulic circuit according to claim 1,characterized in that said helical arrangement (10) is directly molded with said first fitting duct (2).
     
    3. A hydraulic circuit according to claim 1,characterized in that said helical arrangement (11)is an helical element (11) added to the inner smooth surface of said first fitting duct (2).
     
    4. A hydraulic circuit according to claim 1, characterized in that said circuit is of a static type with respect to the swinging or vibrating movements of the basin (21) of said washing machine.
     
    5. A hydraulic circuit according to one or more of the preceding claims, characterized in that said hydraulic circuit uses the full amount of water present in the basin in order to drive the detersive from the detersive vessel (4) to said basin (21) of said washing machine.
     


    Ansprüche

    1. Ein hydraulischer Kreislauf zum Zuführen von Wasser und eines Waschmittels zu einer Waschmaschine, wobei dieser hydraulische Kreislauf eine erste Anschlußleitung (2) umfaßt, die sich zwischen einem Verteiler (3) dieser Waschmaschine, unterhalb des Waschmittelladebehälters (4), und einer Sammelzone (5) erstreckt, die sich am tiefsten Punkt des hydraulischen Kreislaufes befindet, wobei weiterhin eine zweite Anschlußleitung (20) bereitgestellt ist, die sich zwischen dieser Sammelzone (5) und dem Boden des Beckens (21) der Waschmaschine erstreckt, wobei diese Sammelzone den Körper (5) einer Drainagepumpe umfaßt, dadurch gekennzeichnet, daß diese erste Anschlußleitung (2) mit diesem Körper mittels eines Auslasses in Verbindung steht, der um 30° bezüglich der Horizontalen geneigt ist, und daß der Querschnitt dieser ersten Anschlußleitung mit einer schraubenförmigen Konfiguration (10, 11) bereitgestellt ist, die angepaßt ist, einen Turbulenzeffekt in der Leitung bereitzustellen, der wirksam ist, das Waschmittel in diesem Wasser wirkungsvoll zu verteilen.
     
    2. Ein hydraulischer Kreislauf gemäß Anspruch 1, dadurch gekennzeichnet, daß diese schraubenförmige Anordnung (10) direkt in dieser ersten Anschlußleitung (2) geformt ist.
     
    3. Ein hydraulischer Kreislauf gemäß Anspruch 1, dadurch gekennzeichnet, daß diese schraubenförmige Anordnung (11) ein schraubenförmiges Teil (11) ist, das der inneren glatten Oberfläche dieser ersten Anschlußleitung (2) hinzugefügt ist.
     
    4. Ein hydraulischer Kreislauf gemäß Anspruch 1, dadurch gekennzeichnet, daß dieser Kreislauf vom statischen Typ bezüglich der schwingenden oder vibrierenden Bewegungen des Beckens dieser Waschmaschine (21) ist.
     
    5. Ein hydraulischer Kreislauf gemäß einem oder mehreren der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß dieser hydraulische Kreislauf die ganze Wassermenge verwendet, die im Becken anwesend ist, um das Waschmittel vom Waschmittelbehälter (4) zu diesem Becken (21) dieser Waschmaschine zu leiten.
     


    Revendications

    1. Un circuit hydraulique pour fournir de l'eau et un détersif à une machine à laver, ledit circuit hydraulique comprenant un premier conduit de raccordement (2) s'étendant entre un manifold (3) de ladite machine à laver, sous le bac de chargement du détersif (4), et une zone collectrice (5) située au point le plus bas du circuit hydraulique, y étant en plus mis en oeuvre un second conduit de raccordement (20) s'étendant entre ladite zone collectrice (5) et le fond de la cuve (21) de la machine à laver, ladite zone collectrice comprenant le corps (5) d'une pompe de drainage, caractérisé en ce que ledit premier conduit de raccordement (2) est couplé audit corps au moyen d'un orifice, qui est incliné de 30° par rapport à l'horizontale, et en ce que ledit premier conduit de raccordement possède une coupe transversale dotée d'un arrangement hélicoïdal (10, 11) adapté à livrer un effect de turbulence dans le conduit qui provoque une distribution efficace du détersif à travers ladite eau.
     
    2. Un circuit hydraulique selon la revendication 1, caractérisé en ce que ledit arrangement hélicoïdal (10) est moulé directement dans ledit premier conduit de raccordement (2).
     
    3. Un circuit hydraulique selon la revendication 1, caractérisé en ce que ledit arrangement hélicoïdal (11) est un élément hélicoïdal (11) ajouté à la surface interne lisse dudit premier conduit de raccordement (2).
     
    4. Un circuit hydraulique selon la revendication 1, caractérisé en ce que ledit circuit est d'un type statique par rapport au mouvements oscillants ou vibrants de la cuve (21) de ladite machine à laver.
     
    5. Un circuit hydraulique selon l'une ou plusieurs des revendications précédentes, caractérisé en ce que ledit circuit hydraulique utilise toute la quantité d'eau présente dans la cuve afin d'entraîner le détersif à partir du bac à détersif (4) à ladite cuve (21) de ladite machine à laver.
     




    Drawing