"APPARATUS TO GENERATE STEAM FOR A HOUSEHOLD APPLIANCE BY MEANS OF A REMOVABLE BOILER" * * * * * FIELD OF THE INVENTION The present invention refers to an apparatus to generate steam, associated with a household appliance, such as for example an iron, a cleaning apparatus or suchlike, and comprising a boiler, of the removable type, associated with a containing body provided with an electrical resistance in order to transform the water into steam. The apparatus according to the present invention comprises a containing body for a single boiler, which is divided into two parts to allow it to be selectively removed from the containing body, and to be quickly replaced with another analogous boiler.

BACKGROUND OF THE INVENTION Apparatuses to generate steam associated with household appliances, such as for example irons, cleaning apparatuses or suchlike, and comprising boilers installed in a fixed manner inside them in order to transform water into steam are known.

The boilers of known apparatuses are normally formed by a container, namely by two half-shells attached together either by means of screws, or welded together, so as to define a sealed chamber, where the water introduced is heated and transformed into steam, by means of an electrical resistance fixed externally, internally, or integrated in the boiler.

Two systems for the introduction of water into the boiler are mainly known.

A first system provides to equip the boiler with a hole in order to allow the boiler to be directly filled with water manually, then to close the boiler with a stopper and

wait for a certain period of time in order to allow the water to transform into steam.

A second system provides to equip the apparatus with a pump, which takes small quantities of water from a tank and transfers it inside the boiler so that the same water can be transformed into steam.

Both these known systems for the introduction of water have serious limitations, however, due to the presence of various minerals in the water, particularly calcium carbonate, or limestone, which is deposited in the boiler.

When the water introduced into the boiler is heated, the calcium carbonate in fact tends to sink to the bottom of the boiler, and to generate scaling which, in time, tends to block the boiler. Furthermore, if a scale of such limestone is dragged outside the boiler, such scaling may also affect other components, such as for example the electro valves or the resistances.

The blocking of the boiler renders the whole apparatus, or household appliance on which it is fitted, un-usable, so that it has to be replaced.

To obviate this shortcoming, boilers that are removable from the containing body have been proposed. In this case, the electric resistance is arranged within the containing body, also made of metal, which then yields heat to the boiler through conduction.

Such known removable boilers, however, have relatively small contact surfaces with the containing body, which causes a limited heating of the water and therefore a low performance as far as the generation of steam is concerned.

Removable boilers with a larger contact surface with the relative containing body are also known, but they normally have very complex clamping means which, in most cases, apart from comprising delicate mechanical components which

will easily deteriorate, require specific technical knowledge in order to remove or insert the boiler.

A removable boiler is also known from the international patent application WO-A-01/74129, in the name of the same Applicant.

One purpose of the present invention is to achieve an apparatus to generate steam provided with a boiler of the removable type which has a large contact surface with the relative containing body, and which can be easily replaced by any user in the event of a malfunction, breakage or blockage due to limestone.

The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art, and to obtain this and other purposes and advantages.

SUMMARY OF THE INVENTION The present invention is set forth and characterized in the main claim, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea.

In accordance with the aforesaid purpose, an apparatus to generate steam according to the present invention comprises at least a boiler suitable to contain the water to be evaporated, a containing body for the boiler and heating means, which are associated with the containing body and/or said boiler, in order to heat the water contained inside the boiler and turn it into steam.

According to a characteristic feature of the present invention, the containing body comprises a fixed part, wherein the heating means and/or temperature control means of said containing body and/or of said boiler can be advantageously arranged, and a mobile part, associated with the fixed part, able to be moved between a closed position

wherein it keeps the boiler clamped, and an open position wherein it allows the boiler to be removed from the containing body.

According to a preferential form of embodiment of the present invention, the boiler has a substantially cylindrical shape. In this case, both the fixed part and the mobile part have a semi-cylindrical shape and each has an axial half-seating, which are able to form, in reciprocal cooperation, a housing seating with a shape mating with that of the boiler, so that the containing body, with the mobile part in the closed position, contacts the largest possible surface of the boiler, optimizing the performance of the latter as far as steam production and the heat exchange between the containing body and the boiler are concerned.

According to another characteristic feature of the present invention, the containing body comprises closing means which can be selectively activated, in order to constrain or release the mobile part with respect to the fixed part.

Such closing means can, for example, consist of a lever pivoted to the mobile part and provided with a snap-in clamping seating attached to a fixed abutment provided on the fixed part of the containing body.

In this way, by de-activating the closing means and moving the mobile part with respect to the fixed one, the boiler can be removed easily and rapidly from the containing body and therefore autonomously from the apparatus to generate steam, so that it can be individually replaced in the event of breakage, malfunctions or blockage due to limestone.

Furthermore, rapid coupling means are provided, able to allow the boiler to be rapidly connected to the functional

means of the apparatus, without the use of utensils, and without requiring specific technical knowledge on behalf of the user to carry out its removal.

This advantage allows a considerable saving in terms of time and maintenance costs of the whole apparatus, and also the costs of managing the spare parts.

A further advantage of the present invention is obtained when the boiler is made entirely of aluminum, as it can be completely recycled after being replaced.

BRIEF DESCRIPTION OF THE DRAWINGS These and other characteristics of the present invention will become clear from the following description of a preferential form of embodiment, given as a non-restrictive example, with reference to the attached drawings wherein: - fig. 1 shows a lateral sectional view of an apparatus to generate steam according to the present invention; - fig. 2 shows a lateral section of an enlarged detail of fig. 1; - fig. 3 is a section from III to III of fig. 1; - fig. 4 shows the apparatus in fig. 1 in the step when the boiler is removed; - fig. 5 is a view from V of an enlarged detail of a containing body of the apparatus in fig. 3.

DETAILED DESCRIPTION OF A PREFERENTIAL FORM OF EMBODIMENT With reference to fig. 1, an apparatus 10 to generate steam according to the present invention is installed, in the case shown here, inside the body 11 of a control box of a steam iron, of the known type and not shown in the drawings.

In this case, the apparatus 10 comprises a water-tight boiler 12, to contain the water, an electrical resistance 13 arranged, as we shall see, next to the boiler 12, to

transform the water into steam, a containing body 27 for the boiler 12, a water feed pump 15, an electro valve 16 (fig. 3) to deliver the steam, and a pair of thermostats 18 (figs. 1,2 and 3), in order to control the temperature of the containing body 27 and of the boiler 12, when the latter is associated with the containing body 27.

The boiler 12 comprises a hollow container 17 (figs. 1 and 2), of a substantially cylindrical shape and closed on one side by a plane wall 17a, and a lid 19, able to close the open side of the container 17 in a water-tight manner, in order to define a tank 20 to contain the water.

The container 17 comprises, outside the wall 17a, a gripping knob 21 which facilitates the operations to grip and remove the boiler 12 from the apparatus 10.

The lid 19 comprises on the outside a rapid water-tight attachment device 22, of the known type and not described in detail, able to connect the boiler 12 to the respective feed pump 15 and electro valve 16 to deliver the steam, without the need to act on levers, bolts or otherwise.

To be more exact, the lid 19 comprises on the inside a water feed pipe 23 and a steam discharge pipe, not shown in the drawings, both communicating with the rapid water-tight attachment device 22 and respectively connected, by means of the latter, to the feed pump 15 and to the electro valve 16 to deliver the steam.

The water feed pipe 23 is provided with an opening 23a arranged in proximity with the plane wall 17a of the container 17, in order to prevent water being transported towards the steam discharge pipe, due to convective movements which are generated inside the boiler during the step when the water is loaded and the steam is delivered.

This configuration of the water feed pipe 23 allows to block the limestone inside the container 17 before its

scales move towards the exterior, passing through the electro valve 16, with the risk of blocking the latter or other components arranged downstream.

The material of which the container 17 and the lid 19 are made, such as for example steel, aluminum, a combination of steel, aluminum or others, can be of any known type and is irrelevant for the purposes of the present invention, as is the production method of such container 17 and lid 19, whether it be by molding, die-casting or otherwise.

The boiler 12 is arranged inside the containing body 27, which is of a substantially cylindrical shape, and consists of a first fixed half-cylinder 29, and a second movable half-cylinder 30. Each half-cylinder 29 and 30 comprises a housing half-seating, respectively 25 and 26, both with a determinate semi-circular shape so that, when said second half-cylinder 30 is next to the first half-cylinder 29 in its closed position, such half-seatings 25 and 26 define a housing seating 28 mating in shape to that of the container 17, so that the containing body 27 contacts the whole circular external surface of the boiler 12.

The electric resistance 13 is fixed to the first half- cylinder 29 and is arranged so that its heat is transmitted to the boiler 12 (fig. 2), so that, inside the latter, the water fed by the pump 15 through the pipe 23 is transformed into steam.

The second half-cylinder 30 is pivoted to the first half- cylinder 29 along one of its edges and is able to be rotated between a closed position (fig. 1) where it holds the boiler 12, and an open position (fig. 4) where it allows the individual boiler 12 to be removed from the apparatus 10.

In this way, the containing body 27 is in contact with a large external surface of the boiler 12, transmitting to

the latter, in an optimum manner, the heat produced by the electric resistance 13.

On the opposite side with respect to the pivoting edge of the two half-cylinders 29 and 30 at least two traction springs 31 (figs. 3 and 5) are provided, able to connect the two half-cylinders 29 and 30, particularly in order to hold the second half-cylinder 30 with respect to the first one 29 when it is in its open position.

A closing lever 32 is provided, parallel to the traction springs 31, pivoted, with a first end, to the second half- cylinder 30, and with its other end provided with a snap-in clamping seating 33 mating in shape with a clamping shaft 35 fixed to the first half-cylinder 29. In this way, the closed position of the containing body 27 is maintained by coupling the snap-in clamping seating 33 to the clamping shaft 35 in removable manner.

Connection means, not shown in the drawings, can be advantageously provided between the closing lever 32 and the outside of the body 11, in order to allow the user to selectively couple or uncouple the snap-in clamping seating 33 from the clamping shaft 35 in a simple, quick manner without needing to open the body 11.

The apparatus 10 as described heretofore functions as follows.

When the limestone which has been deposited inside the boiler 12 due to the water introduced obstructs the opening 23a of the water feed pipe 23, no more steam is generated inside the boiler 12. At this point the user uncouples the snap-in clamping seating 33 from the clamping shaft 35, causing the second half-cylinder 30 to rotate from the closed position to the open position.

Such rotation allows the user to remove the boiler 12 from the containing body 27, lifting it by means of the

gripping knob 21.

A new boiler 12 is then inserted inside the containing body 27, engaging the rapid water-tight attachment device 22 in order to connect the water feed pipe 23 and the steam discharge pipe to the respective feed pumps 15 and the electro valve 16 to deliver the steam.

Then, by acting on the closing lever 32, the user rotates the second half-cylinder 30 to the closed position to determine the initial clamping position of the new boiler 12 in the containing body 27.

The boiler 12 as described heretofore can therefore be removed and repositioned inside its containing body 27 simply by acting on the lever 32 and the knob 21, without having to provide complex mechanical components or components which can deteriorate easily, or requiring particular technical knowledge on the part of the user.

It is clear, however, that modifications and/or additions of parts can be made to the apparatus 10 to generate steam as described heretofore, without departing from the field and scope of the present invention.

For example, angular positioning means can be provided, such as a coupling seating, abutment blocks or others of a known type, able to cause the boiler 12 to be inserted into the containing body 27 according to a pre-determined angular orientation.

According to another variant, the closing lever 32 can be replaced by any known clamping mean, such as, for example, an attachment hook, a bolt type attachment or otherwise.

According to a further variant, automatic removal means can be provided, able to cooperate with said lid 19 in order to push the boiler 12 automatically towards the outside of the containing body 27, therefore making its removal easier.

According to a further variant, the electrical resistance 13 is arranged directly inside the boiler 12, or inserted in the external wall of the latter, rather than in the containing body 27.

Furthermore, the second half-cylinder 30 may not be pivoted to the first half-cylinder 29, but held to the latter by means of two further springs.

It is also clear that, although the present invention has been described with reference to specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of apparatus to generate steam with removable boiler for a household appliance, all of which shall come within the field and scope of the present invention.