EP3715712B1 - Electric household device for producing steam - Google Patents

Description

[The present invention relates to a household appliance for steam straightening comprising a tank in which water is brought to a boil and relates more particularly to a household appliance provided with means for removing scale formed in the tank.

The documents US-B1-6427637 And WO 00/17575 A disclose similar home appliances, the document FR2904683 discloses an apparatus according to the preamble of claim 1.

In these devices where the water boils en masse, the scale, or calcium carbonate, is deposited in the tank in the form of sludge and fine plates. When the quantity of sludge and fine platelets becomes significant, foam forms under the action of the steam bubbles and it can then be driven outside the tank. In the case of an ironing appliance, for example, the entrained scale can block a control solenoid valve or be deposited on the linen, leaving unpleasant traces.

The scale accumulated in the tank must therefore be evacuated periodically to avoid these drawbacks. For example, it is recommended to intervene every ten uses to carry out this cleaning on an ironing device used normally.

It is known, from the document EP2047174 (A2 ) filed by the applicant, to propose a household appliance comprising a tank in which water is brought to the boil and comprising a removable device making it possible to easily remove the scale formed by the boiling of the water in the tank. However, the collection efficiency can still be improved and an object of the present invention is to respond to the drawbacks of the documents of the prior art mentioned above and in particular, to propose a household appliance which allows a collection of scale still more efficient, without compromising the ease of use of the device.

• une chaudière, agencée pour contenir de l'eau à vaporiser,
• des moyens de chauffage de la chaudière, agencés pour chauffer et vaporiser de l'eau contenue dans la chaudière,
• des moyens d'alimentation de la chaudière en eau, agencés pour injecter de l'eau dans la chaudière,
• un dispositif de collecte de tartre agencé dans la chaudière et comprenant au moins un bord supérieur agencé en hauteur par rapport à un fond de la chaudière,

caractérisé en ce que l'appareil comprend des moyens de mesure de niveau d'eau connectés aux moyens d'alimentation, de sorte à maintenir un niveau d'eau dans la chaudière à un niveau prédéterminé se trouvant approximativement à la même altitude que le bord supérieur du dispositif de collecte du tartre dans la chaudière, le bord supérieur se trouvant préférentiellement légèrement immergé ou affleurant la surface de l'eau, pour permettre à des particules de tartre contenues dans de l'eau de passer par-dessus ledit au moins un bord supérieur, de sorte à aller dans le dispositif de collecte de tartre.For this, a first aspect of the invention relates to a household appliance for generating steam, and in particular a steam steaming appliance comprising a steam plant supplying a steaming tool such as an iron or a steaming brush, comprising:

• a boiler, arranged to contain water to be vaporized,
• means for heating the boiler, arranged to heat and vaporize the water contained in the boiler,
• means for supplying the boiler with water, arranged to inject water into the boiler,
• a scale collection device arranged in the boiler and comprising at least one upper edge arranged in height relative to a bottom of the boiler,

characterized in that the apparatus comprises water level measuring means connected to the supply means, so as to maintain a water level in the boiler at a predetermined level lying approximately at the same altitude as the edge top of the scale collecting device in the boiler, the upper edge being preferably slightly immersed or flush with the surface of the water, to allow scale particles contained in the water to pass over said at least one upper edge, so as to go into the limescale collection device.

According to the above implementation, a predetermined (or reference) level of water is defined and maintained in the boiler or heating tank. This predetermined or reference level is chosen taking into account the altitude in the boiler of the upper edge of the scale collection device. In particular, the predetermined level is chosen so that the scale which bubbles in the boiling water is pushed by the eddies (generated by the steam bubbles and/or the convection currents) over the upper edge, to then end up in the scale collection device. In particular, it is understood that the predetermined level of water and the upper edge are approximately at the same altitude in the boiler. Preferably, the upper edge will be slightly submerged (one or two millimeters below the surface for example) or flush with the surface of the water.

Advantageously, the scale collection device comprises a scale collector provided to be removable from the boiler. This allows a user to remove scale without having to drain the boiler, without having to add an anti-scale product.

Advantageously:

• the scale collector has an elongated gutter shape,
• the boiler comprises an orifice provided for inserting the scale collector into the boiler, and reversible fixing means, such as a thread or a quarter turn, to allow mounting/removal of the scale collector. Such an elongated scale collector makes it possible to recover the scale over the entire useful dimension (depth or diameter) of the boiler.

Advantageously, the scale collection device comprises means of separation arranged in the boiler between at least part of the heating means and the predetermined level, so as to shield the passage of bubbles of steam and/or convection current , and thus define a calm water zone in the boiler at the level of the scale collection device. In particular, the separation means are a sheet forming a deflector. Such a baffle defines in the boiler a zone of calm water (in contrast to the rest of the water agitated by the bubbles / currents of convection), conducive to the recovery of scale (by gravity, sedimentation, progressive movement towards the collector tartar).

Preferably, the separation means form an inclined wall extending in its upper part from the zone of calm water/zone of agitated water border to its lower part adjacent to the scale collector. The separation means can be likened to a funnel which guides the scale towards the scale collector. In practice, two inclined plates can be provided on either side of the scale collector, forming a V.

Advantageously, the separating means comprise said at least one upper edge.

Advantageously, the steam-generating household appliance comprises a steam withdrawal valve and a protective wall arranged between the steam withdrawal valve and the predetermined level. Such a protective wall (located above the surface of the water) protects the withdrawal valve by forming a screen against the drops of water projected by the bubbling, and also against any particles of scale present in the water in the boiler.

Advantageously, the protective wall is integrated into the separation means. This limits the parts to be fixed in the boiler. Concretely, a plate can be provided with a first portion with a horizontal edge completely submerged or at surface level (at the predetermined level), and a second portion which is partially submerged, and which extends above the predetermined level, so as to go between the surface of the water and the steam draw-off valve.

Advantageously, said at least one upper edge is arranged at the predetermined level or below the predetermined level.

Advantageously, the water level measurement means comprise a capacitive sensor. Typically, such a capacitive sensor has an electrode at its lower end, and the lower end of the sensor is arranged substantially at the same height as said upper edge. In detail, this capacitive sensor makes it possible to conduct a low-intensity electric current between an electrode at the end of the sensor and the walls of the boiler when the water level comes into contact with it.

The end of the sensor is preferably located directly above the deflector zone and as close as possible to the center of the boiler.

Advantageously, the level measuring means are arranged in a central portion of the boiler, the central portion preferably having a radius of less than 5 cm. Such an arrangement makes it possible to limit variations in filling level, even if the user does not place the device on a horizontal support.

Advantageously, the level measuring means are offset from the scale collector. According to this implementation, the level sensor is offset from the scale collector, which avoids any interference between these elements during the assembly/dismantling phases of the scale collector.

Advantageously, the steam-generating household appliance comprises a water tank connected to the supply means.

Advantageously, the supply means comprise a pump.

• [Fig. 1] représente une vue d'un appareil de production de vapeur selon la présente invention ;
• [Fig. 2] représente une vue en perspective d'une chaudière de l'appareil de production de vapeur de la figure 1 ;
• [Fig. 3] représente une vue éclatée en perspective de la chaudière de la figure 2 ;
• [Fig. 4] représente une vue en coupe de la chaudière de la figure 2 ;
• [Fig. 5] représente une autre vue en coupe de la chaudière de la figure 2 ;
• [Fig. 6] représente un détail de la figure 5, lors de l'utilisation de l'appareil de production de vapeur.

Advantageously, the steam generating household appliance comprises a control unit connected to the water level measuring means and to the supply means.

• [ Fig. 1 ] shows a view of a steam generating apparatus according to the present invention;
• [ Fig. 2 ] shows a perspective view of a boiler of the steam generating apparatus of the figure 1 ;
• [ Fig. 3 ] shows an exploded perspective view of the boiler of the figure 2 ;
• [ Fig. 4 ] shows a sectional view of the boiler from the figure 2 ;
• [ Fig. 5 ] shows another sectional view of the boiler from the figure 2 ;
• [ Fig. 6 ] represents a detail of the figure 5 , when using the steam generating device.

DETAILED DESCRIPTION

With reference to the Fig. 1 , this represents a perspective view of a steam generating apparatus according to the invention, with in dotted lines a steam generating boiler 10, which will be detailed in the following figures, a pump 31 for supplying water to the the boiler 10, and a water tank 32 which is connected to the pump 31. Typically, the apparatus of the figure 1 is a steam generator that supplies a steam iron through a cord connecting the steam generator to the iron.

There figure 2 represents the boiler 10, that is to say a heating tank comprising a lower tank 11 and an upper tank 12. Typically, the boiler 10 is made of sheet metal, preferably of a material which resists heat and corrosion , that is to say in lacquered steel, stainless steel, or aluminum.

Boiler 10 is equipped with heating means 20, an electric resistor which is affixed to the lower surface of boiler 10. A circular or U-shaped path of the electric resistor can be provided, and one can also provide an intermediate floor between the boiler 10 and the heating means 20, to evenly distribute the heat.

A steam withdrawal valve 60 is also provided in the upper part of the boiler 10, with a strainer 61 arranged in the boiler 10, as shown in picture 3 For example. Supply means 30 are coupled to the boiler 10 to fill it with water, typically comprising an injection nozzle, coupled to the pump 31 of the figure 1 . Finally, water level measuring means 50 are provided near the center of the boiler 10.

As shown in figure 6 , it is then possible to fill the boiler 10 with water 70 to be vaporized, to a predetermined level NP, measured by the water level measuring means 50, here a capacitive sensor having its measuring end located at the level predetermined NP. The location of the water level measuring means 50 in the center of the boiler 10 makes it possible to guarantee a substantially constant filling level, even if the device is not perfectly horizontal.

There is also provided a scale collection device with in particular a scale collector 43 visible on the figures 3-6 , removable relative to the boiler 10, via a wheel 44 screwed onto the sleeve of the water supply means. The scale collector 43 is in the form of a gutter, and extends all along the boiler 10, that is to say over the major part of its diameter. The user can remove the scale collector 43 by acting on the knob 44 (one can provide a screw, a bayonet coupling, a quarter turn...). It should be noted that the capacitive sensor essentially forming the water level measuring means 50 is offset with respect to the scale collector 43, which avoids any interference between these components, even if the user does not align not perfectly scale collector 43 with its intended location.

In addition, the boiler 10 also contains a deflector 40 which forms separation means in the boiler 10, to define a zone of calm water ZEC, in the part of the liquid above the separation means.

Specifically, and with reference to the figure 6 which shows a detail of the boiler 10 during the generation of steam, the deflector 40 is an inclined plate, which has an upper edge 42 placed substantially at the same height as the predetermined level NP. Consequently, the separation means are located between the heating means and the water 70 which is located in the upper part in the center of the boiler 10. This zone above the deflector 40 is the zone of calm water ZEC, in contrast of the peripheral zone where air bubbles as well as convection currents cause eddies on the surface, in a zone of agitated water ZEA.

We see figure 6 that scale particles 80 (schematized in the form of stars) are carried towards the surface by the vapor bubbles and the convection currents. These scale particles 80 "bubble" on the surface, and end up being pushed by the eddies from the agitated water zone ZEA towards the calm water zone ZEC, over the upper edge 42. Then, these scale particles 80 can fall under the action of gravity, and they will be guided, driven along the slope of the inclined plate of the deflector 40 directly towards the scale collector 43. Thus, the separation means, with their upper edge flush or substantially below the surface, allow effective collection of scale particles 80.

On the figures 3, 4 And 5 , it can be seen that the separation means formed by the deflector 40 are essentially a V-shaped plate which converges towards the scale collector 43. The deflector 40 comprises two essentially horizontal edges 41 and 42 on either side of the scale collector 43 , which helps to guide a large amount of scale particles 80.

In addition, the deflector 40 comprises a portion of sheet metal which rises above the predetermined level NP, under the strainer 61 of the steam withdrawal valve 60. This part of the deflector forms a protective wall or a screen for droplets of water or particles of scale which would be projected from the bubbling surface of the water 70 towards the strainer 61 of the steam withdrawal valve 60. Consequently, this screen portion avoids seeing water or impurities carried away with vapor, which increases the overall quality of the device.

Furthermore, it should be noted that the cold water supply is located so as to open into the liquid water zone directly above the scale collector 43: in this way the finest particles of scale created immediately during of the thermal shock linked to the heating of the water entering the boiler are located in the collection zone and are more easily captured. 1

Claims (15)

1. Electric household device for producing steam, and in particular a steam device for removing wrinkles comprising a steam generating unit supplying a wrinkle removing tool such as an iron or wrinkle removing brush, comprising:

   - a boiler (10), arranged to contain the water to be vaporised,

   - heating means (20) of the boiler (10), arranged to heat and vaporise the water contained in the boiler (10),

   - supplying means (30) for supplying the boiler (10) with water, arranged to inject water into the boiler (10),

   - a scale collection device arranged in the boiler (10) and comprising at least one upper edge (41, 42) arranged at a height with respect to a bottom of the boiler (10), in order to allow scale particles (80) contained in the water to pass over said at least one upper edge (41, 42), in such a way as to go into the scale collection device,

   characterised in that the device comprises means for measuring the water level (50), connected to the supplying means (30), in such a way as to maintain a water level in the boiler (10) at a predetermined level (NP) located at approximately the same altitude as the upper edge (41, 42) of the scale collection device in the boiler (10), the upper edge (41, 42) preferably being located immersed or flush with the surface of the water.
2. Electric household device for producing steam according to the preceding claim, wherein the scale collecting device comprises a scale collector (43) that can be removed from the boiler (10).
3. Electric household device for producing steam according to the preceding claim, wherein:

   - the scale collector (43) has an elongated gutter shape,

   - the boiler (10) comprises an orifice provided to insert the scale collector (43) into the boiler (10), and reversible means of fastening, such as a threading or a quarter turn, to allow for an assembly/disassembly of the scale collector (43).
4. Electric household device for producing steam according to one of the preceding claims, wherein the scale collection device comprises separating means arranged in the boiler (10) between at least one part of the heating means (20) and the predetermined level (NP), in such a way as to shield bubbles of steam and/or convection current from passing, and thus define a calm zone of water in the boiler (10) at the scale collection device.
5. Electric household device for producing steam according to the preceding claim, wherein the separating means comprise said at leas one upper edge (41, 42).
6. Electric household device for producing steam according to one of the preceding claims, comprising a steam withdrawal valve (60) and a protection wall arranged between the steam withdrawal valve (60) and the predetermined level (NP).
7. Electric household device for producing steam according to the preceding claim in its dependence with one of claims 4 or 5, wherein the protection wall is integrated into the separating means.
8. Electric household device for producing steam according to one of the preceding claims, wherein said at least one upper edge (41, 42) is arranged at the predetermined level (NP) or below the predetermined level (NP).
9. Electric household device for producing steam according to one of the preceding claims, wherein the means for measuring the water level (50) comprise a capacitive sensor.
10. Electric household device for producing steam according to one of the preceding claims, wherein the means for measuring the water level (50) are arranged in a central portion of the boiler (10), the central portion preferably having a radius less than 5 cm.
11. Electric household device for producing steam according to claim 2 or according to one of claims 3 to 10 in their dependence with claim 2, wherein the means for measuring the water level (50) are offset from the scale collector (43).
12. Electric household device for producing steam according to one of the preceding claims, comprising a water tank (32) connected to the supplying means (30).
13. Electric household device for producing steam according to one of the preceding claims, wherein the supplying means (30) comprise a pump (31).
14. Electric household device for producing steam according to one of the preceding claims, comprising a control unit connected to the means for measuring the water level (50) and to the supplying means (30).
15. Electric household device for producing steam according to the preceding claim, forming a steam generating unit, comprising in particular a steam iron and/or a steam cleaning broom.

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