WO2008017926A2

WO2008017926A2 - Household appliance with detergent dispenser mounted on drum doors

Info

Publication number: WO2008017926A2
Application number: PCT/IB2007/002260
Authority: WO
Inventors: Roberto Vota; Nicola Colucci
Original assignee: Indesit Company S.P.A.
Priority date: 2006-08-07
Filing date: 2007-08-06
Publication date: 2008-02-14
Also published as: ITTO20060582A1; WO2008017926A3

Abstract

The present invention relates to a household appliance (1) adapted to carry out wash treatments on items, in particular textile items; it comprises a rotatable drum (3) adapted to contain items to be treated in its cavity (31) and fitted with at least one door (4,5) for loading items to be treated into its cavity (31), a door (7) for accessing the drum (3), and at least one washing agent dispenser (41,51); the dispenser (41,51) is applied to or integrated with the door (4,5).

Description

HOUSEHOLD APPLIANCE ADAPTED TO CARRY OUT WASH TREATMENTS ON ITEMS

DESCRIPTION

The present invention relates to a household appliance adapted to carry out wash treatments on items, in particular textile items, according to the preamble of claim 1.

Such a household appliance comprises a rotatable drum adapted to contain items to be treated in its cavity and fitted with at least one door for loading items to be treated into its cavity, a door for accessing the drum, and at least one washing agent dispenser; in general, the drum has a substantially cylindrical shape and rotates about a substantially horizontal axis within a tub also having a substantially cylindrical shape. A similar household appliance is known, for example, from patent application EP0628651, which describes a top-loading washing machine. In this case, the dispenser is applied to the underneath the door; in order to drain the washing agent completely, a hydraulic action is required in the dispenser which can be obtained, according to said patent application, by using a specific hydraulic circuit and/or from the rotation of the drum, in particular from the action of the water contained in the tub, which is lifted by the rotating drum (the drum paddles -"palmola" in Italian - may also contribute to this effect).

In known household appliances prior to this one, the dispenser was obtained in a drawer of the appliance cabinet, and a specific hydraulic circuit allowed to drain the washing agent.

It is an object of the present invention to provide a dispenser being an alternative to known solutions, in particular which can dispense the washing agent in an effective and complete manner without requiring any specific hydraulic circuit; of course, simplicity and cost are additional important factors taken into account by the present invention, which is intended for application in the field of consumer electronics.

It is another object of the present invention to provide a solution which allows to load the washing agents even after having loaded the items to be treated in the drum.

These and other objects are achieved by the household appliance having the features set out in the appended claims, which are intended as an integral part of the present description. The present invention is based on the idea of associating the dispenser with a door of the drum of the household appliance (as opposed to the door or the glass door bowl of the appliance).

The dispenser thus rotates together with the drum, and can therefore dispense the washing agent directly into the tub, in particular into the drum containing the items to be treated, during the treatment cycles or steps; it follows that no hydraulic circuit is required for dispensing the washing agent.

Furthermore, the dispenser comes in touch with the washing liquid being present in the tub during the wash treatments, so that no hydraulic circuit is required either for completely draining the washing agent or for cleaning the dispenser and its components (in particular its apertures).

Advantageously, several dispensers may be associated, in particular integrated, with one or more doors of the drum.

The dispenser according to the present invention is particularly suited to being associated with a high-capacity or multi-charge dispenser. According to another aspect, the present invention also includes a dispensing device adapted to be actuated, in particular closed and opened, under the effect of the centrifugal force generated by the rotating drum. This is particularly advantageous for a dispenser rotating together with the drum, since it is easy and inexpensive to manufacture. The present invention will become more apparent from the following description and from the annexed drawings, wherein:

Fig. l shows a very schematic sectional side view of a household appliance according to the present invention,

Fig.2 shows a very schematic sectional side view of a detail of the household appliance of Fig. l concerning the doors of the drum, and

Figs.3 show a dispensing device which can be used in a dispenser according to the present invention in two different operating conditions. Said description and said drawings are to be considered as non-limiting examples.

Fig. l shows a top-loading washing machine representing an example of embodiment of the present invention; the present invention is however not limited to such a type of household appliance, since it may also be applied to, for example, a top-loading washing/drying machine.

In Fig. 1 , the household appliance is designated as a whole by reference number 1. It comprises a substantially cylindrical tub 2, having an access aperture 21 in the top area of the appliance 1 ; the aperture 21 is closed by a door 7 which typically seals it hermetically; the door 7 is rectangular in shape and is hinged on one end so that it can pivot about a substantially horizontal axis (see cross and arrow in the drawing). It should be noted that, for example, an hermetically sealed shutter may be arranged under the door 7; in such a case, the door 7 may not provide a hermetic seal.

Inside the tub 2 there is a substantially cylindrical drum 3, which can rotate about a substantially horizontal axis 30 (see cross in the drawing). As known, the drum 3 turns during the various laundry treatments, e.g. "prewash", "wash", "rinse", "spin", "drying". As known, the drum has an inner cavity 31 into which the items to be treated are loaded. Inside the drum 3 there are "paddles" having the function of dragging and/or lifting the items during the treatments; three paddles 6A, 6B and 6C have the same shape, whereas another paddle (made up of elements 41 and 51) has a different shape because it is created by a dispenser, as explained below. In particular, the paddle 6A is bigger and/or heavier than the paddles 6B and 6C because it acts as a compensation paddle adapted to balance the weight of the paddle made up of the elements 41 and 51 and to bring the center of gravity of the paddle system on the axis 30.

The drum 3 has two doors 4 and 5 (matching each other) for loading items to be treated into its cavity through a matching aperture in the drum 3; the doors 4 and 5 are hinged to two respective opposite ends of the aperture in the drum 3 (note the hinge 40 of the door 4 and the hinge 50 of the door 5) in order to allow said doors to be opened and closed; their respective adjacent sides are adapted to match when both doors 4 and 5 are closed (i.e. when the aperture of the drum 3 is closed); known means are provided for coupling the doors 4 and 5 to each other. The dashed line in Fig. l shows the path followed by the above-mentioned opposite ends of the doors 4 and 5 in the access aperture 21 of the tub 2 as said doors are opened.

A first dispenser 41 having its own inner cavity for a first washing agent is associated, in particular integrated, with the door 4; for example, said washing agent may be any detergent (even bleach) or any softener. A second dispenser 51 having its own inner cavity for a second washing agent is associated, in particular integrated, with the door 5; for example, said washing agent may be any detergent (even bleach) or any softener.

As shown, the door 4 is smaller than the door 5; typically, therefore, the dispenser 41 is suitable for a washing agent required in small quantities (e.g. 100-150 ml of softener), whereas the dispenser 51 is suitable for a washing agent required in large quantities (e.g. 200-250 ml of detergent); for example, the ratio between these quantities may be approximately comprised between 1.5 and 2.0. The ratio between the dimensions of the doors does not necessarily imply that the same ratio should be maintained in the respective inner cavities in terms of quantity of washing agent; the ratio between the available volumes of the inner cavities is what counts.

The paddle 6A is heavier than the other two for counterbalancing the weight of the drum 3 in the area of the doors 4 and 5, which is greater because of the presence of the doors 4 and 5 with their coupling means, of the hinges 40 and 50, and of the dispensers 41 and 51. As to the washing agents contained in the inner cavities of the dispensers 41 and 51, it should be taken into account that they are not always in use (e.g. softener), and that during a treatment cycle, e.g. a cycle comprising "wash", "prewash" and "spin" phases, the washing agents are generally dispensed at different times; typically, during the final "spin" phase (i.e. the most critical treatment in terms of drum unbalance, because the drum rotates at its fastest speed), no washing agent remains to be dispensed anymore; therefore, it will be necessary to adopt a compromise solution suitable for the various operating conditions of the household appliance. Fig. l also shows the electronic system of the household appliance, the control panel thereof being provided as a box 8 which, in the illustrated example, is located in the rear, beside the door 7, and protrudes upward. In Fig.2, the two doors 4 and 5 with their respective dispensers 41 and 51 are shown more in detail; the latter are shown both in the closed position (horizontal) and in the open position (vertical); of course, these positions refer to a condition wherein the drum 3 is stationary and the aperture of the drum 3 matches the aperture 21 of the tub 2. The dispensers 41 and 51 are built in the inner side of the doors 4 and 5, respectively, and are so arranged as to protrude toward the cavity 31 of the drum 3 and so shaped as to act, when closed, as a dragging and/or lifting element on the items to be treated, i.e. as a "paddle". Though less advantageously, they may also be so arranged as to protrude outward from the drum 3; in such a case, they will not act as a paddle. Of course, they may also protrude partly inward and partly outward.

Both dispensers 41 and 51 comprise an inner cavity (not shown) adapted to contain a washing agent, and an aperture for loading (manually) the washing agent into said cavity. The dispenser 51 has an aperture 52 on the edge of the door 5 (in particular the edge opposite to the hinge 50); in the example of Fig.2, said aperture corresponds to a whole side of the dispenser and is provided with a grid. When the door is vertical (or very inclined), it is possible to load, for example, detergent into the inner cavity of the dispenser 51 through the grid without it coming out; when the door 5 is closed, the aperture 52 is closed by the edge of the other door 4, thus creating an obstacle which prevents the detergent from flowing out (in any case, the detergent will fall at least partly onto the items to be treated). If the aperture of the drum 3 has one door 5 only, the aperture 52 may be closed by an edge of the aperture of the drum itself. Said dispenser 51 may also have, on its outer surface, a series of holes or an auxiliary grid 53 used for allowing the washing liquid to flow into the inner cavity of the dispenser 51 more easily, resulting in the washing agent being dispensed in the tub 2 more easily as well. In the example of Fig.2, the edge of the door 4 (which is also the edge of the dispenser 41) is almost perfectly conjugated to the edge of the door 5 (which is also the edge of the dispenser 51); thus, there is no risk that the items to be treated might be caught and get trapped between the two edges or that the washing liquid might flow between the two edges and dissolve the washing agent (e.g. a liquid or powder detergent) contained in the inner cavity of the dispenser 51. The washing agent falls directly into the tub 2 and thus also into the cavity 31 of the drum 3, which contains the items to be treated, since the drum 3 has apertures (small holes) typically obtained on its side walls. It follows that the dispenser 51 can dispense, in particular release, the washing agent; in this case, the aperture 52 used for loading the washing agent is also adapted to dispense the washing agent.

The dispenser 41 has an aperture 42 in the area corresponding to the edge of the door 5 (in particular the edge opposite to the hinge 40); in the example of Fig.2, said aperture comprises manual opening/closing means, e.g. a screwed or bayonet-type plug or a non-return valve; as shown in the drawing, the aperture

42 is obtained in a recess of the edge in order to avoid the risk that the items to be treated might be caught, in particular, by the plug. When the door is vertical (or very inclined), it is possible to load, for example, softener into the inner cavity of the dispenser 41 through the aperture 42; before closing the door 4, the aperture 42 is closed by its closing/opening means and the softener cannot therefore come out.

As to the dispenser 41, means are of course provided for dispensing (releasing or metering) the washing agent contained in its inner cavity, i.e. a dispensing device 43, in particular a valve. In the case shown in the example of Fig.2, the device

43 is located on the outer side of the dispenser 41 (i.e. on the outer side of the door 4) and releases the washing agent directly into the tub 2, and thus also into the cavity 31 of the drum 3 containing the items to be treated, since the drum 3 has apertures (small holes) typically obtained on its side walls. As an alternative, the device 43 is located on the inner side of the dispenser 41 and releases the washing agent directly into the cavity 31 of the drum 3 containing the items to be treated. The former solution is to be preferred to the latter because the device 43 cannot get in touch with the items to be treated, in particular textile items, during the treatment cycle or phases thereof, so that it cannot cause damage to the items. In any case, it is advantageous that the device 43 does not protrude from the surface of the drum 3. It can be easily understood from the above description that during one or more phases of a treatment cycle there is liquid (washing or rinsing liquid) in the tub 2, or at least on the bottom thereof, so that the dispensers 41 and 51 (and the various components thereof) are "washed" and kept clean. In the example of Fig.2, two dispensers 41 and 51 are respectively associated, in particular integrated, with the two doors 4 and 5 of the drum 3. It is also possible to provide more than one dispenser associated with the same door and possibly integrated with each other as well as with the door.

It is now worth making some considerations about the dispensing device 43. Said dispensing device 43 must be so conceived as to open and thus allow the washing agent to be dispensed (released or metered) at specific times during a wash cycle; for example, if the dispenser 41 is adapted to be used for prewash detergent, it shall be opened shortly before or after the start of the prewash treatment; if the dispenser 41 is adapted to be used for wash detergent, it shall be opened shortly before or after the start of the wash treatment; if the dispenser 41 is adapted to be used for softener, it shall be opened shortly before or after the start of the rinse treatment.

The device 43 may be opened under the effect of centrifugal force (typically acting on the device 43) and/or temperature (typically the temperature of the device 43) and/or electric and/or magnetic fields (typically applied to the device 43) and/or electric signals (typically received by the device 43).

Fig.3 shows a particular advantageous example of embodiment of a dispensing device 43 which can be used in a dispenser according to the present invention, e.g. the dispenser 41 of Fig.2, in two different operating conditions; Fig.3 A shows the dispensing device in the closed condition, i.e. when the washing agent cannot flow and thus is not dispensed; Fig.3B shows the dispensing device in the open condition, i.e. when the washing agent can flow and thus is dispensed. The device 43 may be opened under the effect of centrifugal force, designated F in Fig.3B.

In Figs.3, 411 designates the wall of the dispenser 41 that faces the outside of the drum 3, which in the case of Fig.2 corresponds to the outer wall of the door 4.

The device 43 is integrated with said wall; as an alternative, the dispensing device may be mounted to said wall. As already mentioned, the dispensing device may also be located on the wall of the dispenser 41 facing the inside of the drum 3; in such a case, the configuration of the dispensing device shall be reversed.

The device 43 comprises at least one inlet 431 (e.g. a relatively large hole in Fig.3) and at least one outlet 432 (e.g. a plurality of relatively small holes in

Fig.3); there is also a mass 430 on which an elastic element 433 (e.g. a coil spring in Fig.3) acts in order to keep the inlet 431 closed.

The mass 430 is subjected to centrifugal force (acting in the direction shown in

Fig.3B) as the drum 3 rotates. If the centrifugal force ( mω²r , as known) is smaller than the elastic force (kx , as known) exerted by the element 433, the mass 430 keeps the inlet 431 closed and the washing agent cannot flow from the cavity of the dispenser 41 to the cavity 31 through the inlet 431 and the outlet 432.

If the centrifugal force ( mω²r , as known) is greater than the elastic force ( kx, as known) exerted by the element 433, the mass 430 opens the inlet 431 and the washing agent can flow from the cavity of the dispenser 41 to the cavity 31 through the inlet 431 and the outlet 432.

Therefore, whether the device 43 of Fig.3 opens or stays closed depends on the mass m of the element 430, on the elastic constant k of the element 433, on the compression x of the element 433, on the angular speed of rotation ω of the drum

3 (and thus of the dispenser 41 and of the device 43), and on the distance r between the device 43 and the center of the drum 3.

When the household appliance according to the present invention comprises two or three dispensers (for two or three washing agents) having a dispensing device similar to that of Fig.3, it is possible to obtain a differentiated release of the washing agents (typically at different times) in a rather simple manner by sizing and/or calibrating the three dispensing devices differently. A first possible solution is to use three equal masses 430 and three different calibrations of the springs 433; a second possible solution is to use three different masses 430 and three equal and equally calibrated springs 433; a third possible solution is to use three equal masses 430 and three different springs 433; as can be easily understood from the above description, additional solutions are also available which address several parameters at the same time, e.g. three different masses 430 and three different springs 433.

A dispensing device of the type as shown in Fig.3 may be made to open not only by the natural conditions of a treatment phase, but also by particular conditions occurring in the household appliance before a treatment phase is started. For example, let us suppose that a household appliance according to the present invention comprises three dispensers fitted with three respective dispensing devices, a first one for detergent, a second one for bleach and a third one for softener, and that the first dispensing device opens when the drum rotates at 100 rpm, the second dispensing device opens when the drum rotates at 200 rpm, and the third dispensing device opens when the drum rotates at 300 rpm. Of course, at low speed (in the above example, less than 100 rpm) all three dispensing devices are closed; therefore, the dispenser can be filled with washing agent at the end of a treatment cycle without the risk of any leaks, since the dispensing devices are closed.

In this case, a first short drum rotation phase at a speed of, for example, 140-160 rpm (i.e. faster than 100 rpm and between 100 and 200 rpm) may be provided before the wash treatment so as to cause the detergent to be released, whereas a second short drum rotation phase at a speed of, for example 240-260 rpm (i.e. faster than 200 rpm and between 200 and 300 rpm) may be provided before the bleaching treatment so as to cause the bleach to be released, and a third short drum rotation phase at a speed of, for example, 340-360 rpm (i.e. faster than 300 rpm) may be provided before the rinse treatment so as to cause the softener to be released. This ensures that during the first short phase only the detergent is released, since only the first device can open at that speed, that during the second short phase only the bleach is released, since both the first and second devices can open at that speed, but the first dispenser is empty; and that during the third short phase only the softener is released because, although all of the first, second and third devices can open at that speed, the first and second dispensers are empty. Such a controlled opening of the dispensing devices is obtained by appropriately controlling the motor of the household appliance by means of the electronic control system.

It is worth mentioning that, in the above example, one could also have used a detergent dispenser lacking any dispensing device, like the dispenser 41 of Fig.2. The dispenser according to the present invention, i.e. associated with the door of the drum, may be advantageously combined in a household washing appliance with a high-capacity or multi-charge dispenser. For example, the detergent may be loaded into the high-capacity or multi-charge device and then metered during the wash phases, while bleach and/or softener may be loaded into one or two devices associated with one or two drum doors. The present invention has been described with reference to a particular embodiment example, but it is clear that many changes may be made thereto by those skilled in the art, and that all said changes will still fall within the scope defined by the appended claims.

Claims

1. Household appliance (1) adapted to carry out wash treatments on items, in particular textile items, comprising: a rotatable drum (3) adapted to contain in its cavity (31) items to be treated, fitted with at least one door (4,5) for loading items to be treated into its cavity (31), a door (7) for accessing said drum (3), and at least one washing agent dispenser (41,51), characterized in that said dispenser (41 ,51) is applied to or integrated with said door (4,5).

2. Appliance (1) according to claim 1 , wherein said dispenser (41,51) protrudes toward the cavity (31) of the drum (3).

3. Appliance according to claim 2, wherein said dispenser (41,51) is also adapted to act as a dragging and/or lifting element on items to be treated.

4. Appliance according to claim 1 or 2 or 3, wherein said dispenser (41 ,51) comprises an inner cavity adapted to contain a washing agent and an aperture

(42,52) for loading a washing agent into said cavity.

5. Appliance according to claim 4, wherein said aperture (42) is fitted with manual closing/opening means.

6. Appliance according to claim 4, wherein the drum (3) includes a closed position for the door (5), which in particular is hinged (50), and is so configured that the aperture (52) of the dispenser (51) is at least partly closed when the door (5) is in said closed position.

7. Appliance according to any of claims 4 to 6, wherein the aperture (52) of the door (5) is located on one edge of the door (5).

8. Appliance according to any of claims 4 to 7, wherein said aperture (52) for loading the washing agent is also adapted to allow the washing agent to be dispensed during a treatment cycle or phase.

9. Appliance according to any of claims 4 to 8, wherein the dispenser (41) comprises a dispensing device (43) adapted to dispense the washing agent contained in said cavity during a treatment cycle or phase.

10. Appliance according to claim 9, wherein said dispensing device (43) is a valve adapted to open during a treatment cycle or phase.

11. Appliance according to claim 10, wherein said dispensing device (43) is a valve adapted to open under the effect of centrifugal force and/or temperature and/or electric fields and/or magnetic fields and/or electric signals.

12. Appliance according to any of the preceding claims, wherein said drum is provided with two matching doors (4,5), in particular hinged, and a dispenser (41,51) is applied to or integrated with each of said two doors (4,5).

13. Appliance according to any of the preceding claims, wherein two or more dispensers are applied to or integrated with a door.

14. Appliance according to claim 13, wherein said two or more dispensers are combined together.

15. Appliance according to any of the preceding claims, characterized by comprising at least two washing agent dispensers, each dispenser comprising a dispensing device adapted to dispense the washing agent, said dispensing devices being adapted to dispense a washing agent at different times.

16. Appliance according to any of the preceding claims, characterized by being a top-loading washing machine or washing/drying machine.