EP4031701B1

EP4031701B1 - Plate unit for a steam iron

Info

Publication number: EP4031701B1
Application number: EP20796666.4A
Authority: EP
Inventors: Riccardo GIROTTO
Original assignee: De Longhi Appliances SRL
Current assignee: De Longhi Appliances SRL
Priority date: 2019-09-20
Filing date: 2020-09-17
Publication date: 2023-10-25
Anticipated expiration: 2040-09-17
Also published as: IT201900016862A1; CN114729497B; WO2021053702A1; CN114729497A; EP4031701A1

Description

FIELD OF THE INVENTION

The present invention concerns a plate unit for an iron provided with an integrated valve unit able to improve the cleaning process of the plate itself, and consequently to prolong its life.
The present invention also concerns a method for cleaning a plate of an iron, which allows to effectively remove possible limescale encrustations and residues without risking blocking the holes for the steam to exit.

BACKGROUND OF THE INVENTION

Irons are known, comprising a plate unit provided with a heating plate defining a steam chamber, into which water is injected which, due to contact with the heating plate, is transformed into steam and exits through holes made in the lower surface of the heating plate itself.
It is also known that one disadvantage of known irons is that, since water is injected into the steam chamber at room temperature, limescale encrustations and deposits can be generated inside it, which can block the passages and/or holes from which the steam exits, causing the steam function of the iron itself to stop.
This causes, especially where the water is rich in limescale, a reduced life of the ironing apparatus, or in any case a frequent need for maintenance.
To preserve the life of the plate units for irons, a washing and cleaning process is therefore generally provided, able to remove, at least partly, the deposits of limescale and/or minerals, which depending on the type of water used for generating the steam can be deposited inside the hydraulic circuit of the plate itself.
For example, solutions for cleaning the plate unit are known, which generally provide a washing cycle, possibly associated with thermal shocks, during which water is introduced into the plate unit, and made to exit from the same holes where the steam usually exits, in order to wash and remove encrustations and mineral deposits.
Solutions are also known which provide a stopper in the rear zone, able to at least partly open the steam chamber of the plate, to improve the cleaning method and have a wide aperture for the outflow of the water used during the cleaning cycle, and of the removed particles, avoiding the risk of blocking the exit holes of the steam during the cleaning step.
US 3,747,241 describes a steam iron equipped with a self-cleaning system, comprising a large aperture made in correspondence with the water tank, associated with a valve that allows it to be emptied quickly.
One purpose of the present invention is to provide a plate unit for an iron that allows to improve the cleaning efficiency of the steam chamber, reducing the risk of blocking the steam emission holes during cleaning operations.
Another purpose of the present invention is to provide a plate unit for an iron that allows maintenance and cleaning operations to be carried out quickly and effectively.
Another purpose is to provide a plate unit for an iron that allows to obtain a high outflow speed of the water, the dissolved particles and the possible steam from the steam chamber, reducing the cleaning times of the plate unit to a minimum.
Another purpose of the present invention is to perfect a method for cleaning the plate unit which is effective and rapid.
The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claim. The dependent claims describe other characteristics of the present invention or variants to the main inventive idea.
In accordance with the above purposes, the present invention concerns a plate unit for an iron comprising a heating block and an upper closing lid which define inside them a steam chamber in which steam is generated.
In the closing lid there is normally provided an entry aperture for the water, through which the water is injected into the steam chamber.
The plate unit also comprises a steam distribution chamber, which is connected to the steam chamber by passage ducts for the steam, and is delimited at the lower part by an ironing soleplate provided with holes and/or apertures for the steam to exit.
According to one aspect of the present invention, the plate unit comprises a valve unit integrated inside it and configured to optimize the cleaning operations of the plate itself. In particular, this valve unit allows to reduce the risk of blocking the holes and passages for the exit of steam during the cleaning operations, and to reduce the time required for the cleaning operation itself.
In particular, the valve device is selectively drivable to open and close a discharge aperture provided in the steam chamber in order to allow the discharge of the water directly therefrom to the distribution chamber, without the water having to pass through the channels that connect the steam chamber and the distribution chamber.
Thanks to the valve device integrated in the plate unit, it is possible to perform the cleaning cycle in a simple and effective manner, without needing to remove any component whatsoever, such as for example a stopper or a manifold, from the ironing apparatus.
According to some embodiments, the valve device comprises a fixed valve body and a shutter body mobile with respect to the valve body and the discharge aperture in order to open and close the latter.
According to some embodiments, the shutter comprises a stem provided on a lower end of a shutter portion having a width greater than the diameter of the stem.
The stem of the shutter is conformed to move axially, sliding in a guide of the valve body, with respect to the valve body itself. The shutter portion is configured to act on one side, or a lower surface, of the discharge aperture, determining its opening and closing.
In particular, the shutter portion can cooperate directly with the lower surface of the wall that delimits the steam chamber and the steam distribution chamber.
In the steam ironing position, the shutter portion blocks the discharge aperture so that the generated steam is induced to pass through the transit channels toward the distribution chamber and exit from the dedicated apertures, provided in the soleplate.
In the cleaning position, the valve device is driven so as to open the discharge aperture, and the water injected into the steam chamber can flow directly through it. According to some embodiments, it can also be provided that on the ironing soleplate there are provided through holes located in correspondence with the discharge aperture and the valve device, so that, during the cleaning operations, when the valve device is driven, the water can be discharged directly through them, without passing through the holes and apertures dedicated to the passage of steam.
In this way, advantageously, the limescale residues dragged by the cleaning water are prevented from obstructing the holes dedicated to the passage of steam, compromising the effectiveness of the functioning of the ironing apparatus.
During the cleaning step, the plate can be disposed in an inclined manner, so that the discharge aperture is lower than the water entrance area, thus exploiting the force of gravity to promote the exit of the water, introduced during cleaning, and of the particles and residues of limescale present therein.
The present invention also concerns a method for carrying out the cleaning of a plate unit for an ironing apparatus, which provides to inject water into the steam chamber and drive a valve device to selectively open a discharge aperture provided in the steam chamber in such a way as to discharge the water and possible limescale particles and residues from the steam chamber without it passing through the channels dedicated to the passage of steam.
These and other aspects, characteristics and advantages of the present disclosure will be better understood with reference to the following description, drawings and attached claims. The drawings, which are integrated and form part of the present description, show one embodiment of the present invention, and together with the description, are intended to describe the principles of the disclosure.

ILLUSTRATION OF THE DRAWINGS

These and other characteristics of the present invention will become apparent from the following description of some embodiments, given as a non-restrictive example with reference to the attached drawings wherein:

fig. 1 is a top plan view of a plate unit with an integrated valve device according to some embodiments described here;
fig. 2 is a section view of the plate unit of fig. 1 according to the section line II-II;
fig. 3a is an enlarged detail of fig. 2 in which the valve device is in a closed operating position;

fig. 3b is an enlarged detail of fig. 2 in which the valve device is in the open operating position;
fig. 4 is a top plan view of the plate unit according to some embodiments described here without the upper closing lid;
fig. 5 is a bottom plan view of the plate unit of fig. 1.

To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one embodiment can conveniently be incorporated into other embodiments without further clarifications.

DESCRIPTION OF EMBODIMENTS

We will now refer in detail to the various embodiments of the invention, of which one or more examples are shown in the attached drawings. Each example is supplied by way of illustration of the invention and shall not be understood as a limitation thereof. For example, the characteristics shown or described insomuch as they are part of one embodiment can be adopted on, or in association with, other embodiments to produce another embodiment. It is understood that the present invention shall include all such modifications and variants.
Embodiments described here with reference to the attached drawings 1-4 concern a plate unit 10 for a steam ironing apparatus, in particular suitable for an ironing apparatus of the type defined as "cold", that is, in which the steam is generated directly inside the plate unit 10 itself.
The plate unit 10 comprises a heating block 12 and an upper closing lid 13, which define inside them a steam chamber 19.
The upper lid 13 is provided with a water entrance aperture 14, connected during use to an injection duct, not shown, through which water is fed into the steam chamber 19.
The water is transformed into steam when it comes into contact with a hot wall of the heating block 12 defining the bottom wall 30 of the steam chamber 19.
The water comes into contact with the wall 30 in correspondence with a water entrance area 14A disposed in a position coherent with the water entrance aperture 14 and the inclination of the iron provided with the plate unit 10.
The steam chamber 19 can be conformed with a variable geometry, in order to maximize the vaporization of the water introduced through the water entrance aperture 14.
The lower surface of the plate unit 10 is then delimited by an ironing soleplate 11, which constitutes the contact surface between the plate unit 10 and the fabrics to be ironed.
Such soleplate 11 comprises a plurality of holes, or through apertures 26 which allow the steam to exit.
The heating block 12 and the ironing soleplate 11 define, one with the other, a steam distribution chamber 28, which is connected to the steam chamber 19 by means of ducts for the passage of steam, not shown. In this way, the steam generated in the steam chamber 19 is conveyed toward the distribution chamber 28 in which it is distributed in such a way as to obtain a uniform delivery of the steam through the dedicated apertures 26.
According to one aspect of the present invention, the steam chamber 19 also comprises at least one discharge aperture 17 configured to allow the discharge of the water directly from the steam chamber 19 to the distribution chamber 28, separate and distinct from the passage ducts of the steam.
According to a preferred embodiment, the steam chamber 19 has a longitudinal conformation, in which the water entrance area 14A is disposed at one end, and the at least one discharge aperture 17 is positioned in proximity to the opposite end.
In the heating block 12 there can therefore be made one or more discharge apertures 17, which can be disposed more or less close to the end of the steam chamber 19, as a function of its conformation.
According to some embodiments, the plate unit 10 comprises a valve unit 20 integrated inside it.
The valve unit 20 is selectively drivable to open and close the discharge aperture 17 and allow a direct discharge of the water from the steam chamber 19 to the distribution chamber 28.
According to some embodiments, the valve unit 20 comprises a valve body 25 fixed with respect to the heating block 12 and a shutter body 21 axially mobile with respect to the valve body 25 and the discharge aperture 17.
According to some embodiments, the shutter body 21 is of the poppet valve type, which has advantageous characteristics of efficiency, practicality and cost compared to other shutter devices.
The shutter body 21 can comprise a stem 22 and a mushroom-shaped or umbrella-shaped shutter portion 23, provided in correspondence with a lower end thereof facing, during use, toward the soleplate 11.
The shutter portion 23 acts on the discharge aperture 17, determining its opening and closing, respectively moving away from and toward the wall 30 delimiting the steam chamber 19 and the distribution chamber 28.
The area of the shutter portion 23 is greater than or equal to that of the discharge aperture 17, preferably greater, so as to guarantee a hermetic closure of the latter during normal ironing operations.
The width of the shutter portion 23 can be indicatively equal to 3 times the diameter of the stem 21. In this way, it is possible to obtain in the heating block 12 a discharge aperture 17 with a diameter greater than the diameter of the stem 22, for example equal to 2 times the latter.
Providing a stem 22 of a smaller size than the size of the discharge aperture 17 allows to optimize the outflow speed of the water from the steam chamber 19, of the dissolved particles and of the possible steam generated in the step of cleaning the ironing apparatus, reducing the time required for this operation.
According to some embodiments, the soleplate 11 has, in a zone located in correspondence with the discharge aperture 17, a plurality of holes or apertures 27 for the water having sizes preferably larger than the apertures 26 for the exit of steam (see fig. 5). In this way, during use, the water discharged from the discharge aperture 17 can be made to exit through the apertures 27 for the water, without passing through the apertures 26 for the steam, preventing the risk of possible obstructions thereof.
The stem 22 slides in a guide of the valve body 25, which can be mounted by means of attachment means, such as for example screws, onto an upper surface of the upper closing lid 13.
According to a further embodiment, the body of the valve(s) 25 can be integrated into the upper closing lid 13.
According to some embodiments, the shutter portion 23 comprises an external edge 29 inclined by an angle of inclination α with respect to the axis of the valve itself, presenting a flared shape toward the lower end.
According to some embodiments, the angle of inclination α can for example be comprised between 30° and 60°, for example about 45°.
According to other variants, the angle of inclination α can vary from 0° up to the theoretical maximum limit of 90°.
According to some embodiments, in order to obtain an optimal seal of the valve unit 20, the wall 30 comprises, made on its lower side, a seating 24 configured to house the shutter portion 23 in the position in which the valve unit 20 is closed.
According to some embodiments, the lateral walls of the seating can have an angle of inclination correlated to that of the outer edge 29, so as to create with it a broad sealing surface.
According to some embodiments, the seating 24 can have a depth correlated to the height of the shutter portion 23 so that, in the closed condition, a lower surface 16 of the shutter portion 23 is positioned perfectly flush with the lower surface of the wall 30.
With reference to fig. 3a, in a position of normal use (steam ironing), the shutter portion 23 blocks the discharge aperture 17, positioning itself inside the seating 24, so that the steam generated is induced to exit through the ducts for the passage of steam and the apertures 26 of the soleplate 11.
According to some embodiments, the closure of the discharge aperture 17 occurs by means of contact between the shutter portion 23, which could also be equipped with one or more gaskets (not shown here), and a lower surface 18 of the seating 24 of the valve, made in the wall 12.
During the maintenance and cleaning operations of the plate unit 10, the stem 22 is driven axially and in such a way that the shutter portion 23 disengages and moves away from the discharge aperture 17 and from the seating 24. In this way, the preferential passage is allowed of the water, the dissolved particles and the possible steam generated by the steam chamber 19 in the distribution chamber 28 and the dedicated water exit apertures 27 provided in the soleplate 11, limiting the risk that some particles can be forced to exit through the holes 26 for the steam to exit, blocking them. With reference to figs. 3a and 3b, it is possible to note the different position of the stem 22 and of the shutter portion 23, respectively in the closed and open position, where in the closed position the distance D between one internal surface 15 of the soleplate 11 and the lower surface 16 of the shutter portion 23 is maximum, while in the open position this distance D is zeroed, so as to allow the maximum passage through the discharge aperture 17.
According to other embodiments, as a function of the conformation of the steam chamber 19, of the distribution chamber 28 and of the stroke of the stem of the poppet valve 22, the distance D in the open position can be greater than zero, that is, the distance between the internal surface 15 of the soleplate 11 and the lower surface 16 of the shutter portion 23 can be different from zero, but become minimal, in any case allowing the maximum passage area through the discharge aperture 17.
In accordance with what has been described above, according to the disposition of the discharge aperture(s) 17, it is possible that during the cleaning operations the iron is disposed on an inclined plane, so as to position the discharge aperture(s) 17 lower than the water entrance area 14A, so as to exploit the force of gravity in order to promote the exit of the water introduced during the cleaning, and advantageously of the dissolved particles.
According to other embodiments, the shutter 21 can be made with the lower end 23 in different shapes, for example with cylindrical or truncated-conical symmetry. The corresponding seating 24, made in the heating block 12, will have a lower surface 18, of the discharge aperture 17, mating in shape with the shutter portion 23 of the shutter 21, which goes to rest on it, obtaining a seal in the position of valve closed or of normal use of the iron.
According to further embodiments, the seating 24 can be not present in the heating block 12, with only the discharge aperture 17 being present, so that in the closed valve position the shutter portion 23 contacts the upper surface of the distribution chamber 28 by means of suitable sealing gaskets, disposed on the upper surface of the shutter portion 23.
According to another embodiment, it can also be provided that the shutter 21 has a substantially cylindrical shape with a constant diameter along its length, provided with a concavity, or with a notch made in correspondence with a lower portion thereof. In order to allow the preferential passage of the water, the dissolved particles and the possible steam generated through the discharge aperture 17 during the cleaning steps, the shutter 21 can be moved so as to position the concavity, or the notch, in correspondence with the discharge aperture 17 itself, thus defining a channel for the passage of the water. In the closed valve position, the shutter 21 can guarantee the seal of the discharge aperture 17 through suitable gaskets, housed on the shutter itself.
It is clear that modifications and/or additions of parts may be made to the plate unit 10 and to the valve unit 20 as described heretofore, without departing from the field and scope of the present invention.
It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of plate unit 10 and valve unit 20 and method for cleaning a plate unit 10, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.
In the following claims, the sole purpose of the references in brackets is to facilitate reading: they must not be considered as restrictive factors with regard to the field of protection claimed in the specific claims.

Claims

Plate unit for a steam iron, comprising an ironing soleplate (11) provided with a plurality of holes (26) for the steam to exit, a heating block (12), an upper closing lid (13) provided with an entrance (14) for the water, a steam chamber (19) enclosed between said heating block (12) and said closing lid (13) and a steam distribution chamber (28) enclosed between said heating block (12) and said soleplate (11) and fluidically connected to said steam chamber (19) by means of steam distribution channels, wherein the plate unit comprises at least one valve unit (20) selectively drivable to open and close at least one discharge aperture (17) made in a wall (30) of said heating block (12) in order to allow a direct discharge of the water from said steam chamber (19) to said steam distribution chamber (28), and characterized in that said soleplate (11) comprises, in correspondence with said discharge aperture (17), a plurality of holes or apertures (27) for the water, which have larger sizes than said holes (26) for the steam to exit, in order to allow the direct exit of the water from said distribution chamber (28) toward the outside.
Plate unit as in claim 1, characterized in that said valve unit (20) comprises at least one fixed valve body (25) and a shutter body (21) mobile with respect to said valve body (25) and to said discharge aperture (17) and configured to open and close the latter.
Plate unit as in claim 2, characterized in that said shutter body (21) comprises a stem (22) provided, on a lower end thereof, with a shutter portion (23) that has an extension greater than or equal to that of said discharge aperture (17).
Plate unit as in claim 3, characterized in that said wall (30) comprises, made on a lower side thereof, a seating (24) configured to house said shutter portion (23) in the position where said valve unit (20) is closed.
Plate unit as in any claim hereinbefore, characterized in that said steam chamber (19) has a longitudinal conformation, wherein a water entrance area (14A) is disposed at one end, below said entrance (14) for the water, and said at least one discharge aperture (17) is positioned in proximity to the opposite end.
Method for cleaning a plate unit of a steam iron, as defined in one of claims 1-5, which provides to:
- introduce water into a steam chamber (19) provided in a heating block (12) through an entrance (14) for the water made in a closing lid (13);

- generate steam in said steam chamber (19) by means of contact of the water with said heating block (12) in a water entrance area (14A);

- activate a valve unit (20) disposed in said plate unit (10) in order to open a discharge aperture (17), provided in a wall (30) of said heating block (12), and to directly discharge the water, together with the steam and possible solid residues from said steam chamber (19) into a steam distribution chamber (28) defined between said heating block (12) and an ironing soleplate (11), without it passing through dedicated channels for the passage of steam, and in that it provides to discharge the water from said distribution chamber (28) through dedicated apertures (27) for the water provided in said soleplate (11) in correspondence with said discharge aperture (17).
Method for cleaning as in claim 6, characterized in that during the introduction of the water into said steam chamber (19) it provides to maintain the iron inclined so that the discharge aperture (17) is at a lower height than said water entrance area (14A), and the water introduced, together with the dissolved particles and the possible steam generated, can flow by gravity through said discharge aperture (17), distribution chamber (28) and apertures (27) for the water.
Method for cleaning as in either claim 6 or 7, characterized in that the activation of said valve unit (20) provides to axially drive a stem (22) of a shutter unit (21) with respect to a fixed body of the valve (25) so as to move a shutter portion (23) of said shutter unit (21) toward said soleplate (11) and move it away from said discharge aperture (17), determining the opening of the latter.
Method for cleaning as in any claim hereinbefore, characterized in that at the end of the maintenance and cleaning operations it provides to deactivate said valve unit (20) and close said discharge aperture (17).