Under fireplace any combustion chamber for fires of various kinds is meant: home fireplaces, thermo- fireplaces, wood-fired ovens, wood-or coal-fired boilers, wherein the oxygen necessary to the combustion is provided by environmental air. To this purpose, the subject fireplace is opened, half-opened or, in any case, ventilated.

Various ventilation and draught systems are known. They are used to provide a better draught to a flue and anyway to guarantee an efficient ventilation to the fireplace.

This kind of systems, however, utilizes a flue or an existing chimney, in order to scavenge the smokes above the roof's level, not only to avoid that the smoke impurities are released at the ground level, but also to avoid dispersing the superheated smoke.

It is meant then that the known systems cannot fit in logistic and architectonical situations wherein a flue is not possible or it is difficult to implement.

In these cases, it is necessary to renounce to the installation of fireplaces or, for example, to make do with electric ovens which, as it is known, do not provide the same cooking performances compared to a wood-fired oven involving a fireplace.

The technical problem underlying the present invention is to provide a suction system enabling to obviate to the drawbacks mentioned with reference to the known art.

Such problem is solved by a suction system apt to be associated to a fireplace comprising: * a device of forced ventilation to extract smoke from a combustion chamber of the fireplace;

* a plurality of filter units wherein the devices necessary to cool and purify the extracted smokes are contained comprising: a plurality of sprayers fed with washing liquid; a ionization chamber; filtering chambers, filled-up with filtering material; * refrigerating means for the washing liquid to keep the washing temperature below a certain level, so that the whole temperature of the system remains contained, as well as the temperature of the smokes expelled from the system.

The main advantage of the suction system according to the present invention is. to enable the installation of fireplaces even in inappropriate sites, by providing the possibility to suck the produced smoke by correctly feeding the combustion and correctly eliminating each product of the combustion.

Such system may have a modular structure and it may be placed in narrow spaces, for example balconies, small. courtyards and the like.

The present invention will be here below described according to a preferred embodiment thereof, illustrated by way of example and not for limitative purposes with reference to the enclosed drawings wherein: * figure 1 is a partially-sectional perspective view of a suction system according to the invention; and * figure 2 is a cross-sectional view of the system of figure 1.

By referring to the figures, a suction system is designated as a whole with 1. It is apt to be associated to a fireplace of any nature, for example a home fireplace, a thermo-fireplace or a wood-fired oven of the kind used in restaurants,"pizzeria"or in home environment, which is not represented in the figures and which is equipped with a conventional exhaust at the vault of the combustion chamber.

To said exhaust an extraction duct 2 is connected which flows in a device of forced ventilation 3, in particular

a centrifugal blower, manufactured so as to stand the temperatures of the extracted smoke coming out from the combustion chamber already mixed with air. The device of forced ventilation 3 is equipped with a casing 4 containing a centrifugal rotor 5 driven by a first motor 6 by means of a shaft 7.

Said casing 4 is opened onto a first filter unit 8 delimited by a first box-shaped container 9. The system 1 further comprises a second filter unit 10 with a respective second box-shaped container 11 and a third filter unit 12 with a third box-shaped container 13.

The filter units 8,10,12 are parallelepiped-shaped and the respective box-shaped containers 9,11,13 are implemented by means of sheared plate walls. Said units 8,10,12 are stacked one onto the other, to form a filtering column, overlapped at the respective sides with larger surface.

The casing 4 of the device of forced ventilation 3 is opened at a first end wall 14 of the first unit 8, the opposite second end wall 15 is connected to the below first end wall 16, following the smokes'running direction, of the second unit 10. Likewise the second end wall 17 of the second unit 10 is connected to the first end wall 18 of the third unit 12. The connection is implemented, in both cases, by a respective first and second U-shaped duct 19,20.

At the second end wall 21 of the third unit 12, the latter comprises an exhaust port 22 equipped with a grate. Such port 21 could be connected to an exhaust duct 23.

The units 8,10,12 constitute a series of modular filter units, implemented with box-shaped containers with equal shape and sizes. Inside the units 8,10,12 the devices necessary to cool and purify the smokes extracted from the device of forced ventilation 3 are contained.

In the units 8,10,12 the smokes run along a winding route, capable of optimizing the room occupied by the units 8,10,12.

In the first unit 8, the system comprises first means for washing the smokes, comprising a plurality of sprayers 24 arranged on the upper wall 25 of the first box-shaped container 9. Said sprayers are arranged along the longitudinal development, of said container 9.

The first unit 8 is substantially divided into a ionization chamber 26, whereonto the casing 4 of the device of forced ventilation 3 is opened, and a first filtering chamber 27, filled-up with filtering material 28, for example spongy and/or fibrous material such as glass wool.

The second unit 10 too is wholly equipped with sprayers 24 and it is wholly filled-up with said filtering material 28, by implementing a single second filtering chamber.

The third unit 12 is divided, by following the smokes' running direction, into a third filtering chamber 29, followed by a dust reduction chamber 30, by a fourth, fifth and sixth filtering chamber 31,32,33 with increasing density of the material, to trap the finest particles.

The sprayers 24 are arranged, for the third unit 12, in the third filtering chamber 29 and in the reduction chamber 30.

The fifth chamber 32, to catch the finest particles, has a filtering material filtering material saturated with tackifying and not siccative products.

The sixth chamber 33 comprises means for deodorizing the smoke, that is substances saturated in the filtering material releasing vapours in the smoke.

Soon after the sixth chamber 33, the third unit 12 comprises a device for expelling the smokes 34, comprising an axial fan 35 driven by a not-shown motor.

By going back to the beginning of the smokes'route, the ionization chamber comprises a ionization plate 36 apt to negatively charge the smokes. The function of this chamber and of the sprayers 24 will be clearer from the description of the operation of the system 1.

The sprayers 24 of each unit are respectively fed by a first, a second and a third delivery duct 37,38,39 fed by a main delivery duct 40.

On the respective bottoms 41,42,43 of each unit 8,10, 12 the nebulized washing water, come into contact with the smokes, is collected. Each bottom is connected to a respective first, second and third collecting duct 44, 45,46, connected to a main collecting duct 47 flowing into a first collecting tank 48. Such tank is also fed by a feeding duct 49 to recharge the washing liquid.

A first circulation pump 50, driven by a second motor 51, carries the water of the first tank 48, through a circulation duct 52, to refrigerating means 53 for the washing liquid.

Such refrigerating means 53 is used to keep the washing temperature below a certain level, so that the whole temperature of the system 1 remains contained, as well as the temperature of the smokes expelled from the system 1.

It comprises a second tank 54 containing a refrigerated serpentine 55 or other refrigerating member, cooled by a conventional refrigerating device designated with 56. A second circulation pump 57, driven by a respective third motor 58, provides for sending the refrigerated water to the main delivery duct 40.

Since the description of the structure of the system 1 is completed, hereinafter the operation thereof will be described.

The smokes are sucked by the device of forced ventilation 3 from the combustion chamber of the fireplace and are entered the ionization chamber 26 wherein they undergo a first washing combined with a ionization which negatively charge the smokes.

Soon after, in the various passages inside the filtering material 28, the smoke particles, already negatively charged, are compelled to follow a tortuous route with continuous changes in direction which make the deposit on the filtering material 28 easier.

It is to be noted that the second unit, arranged between the first and the second unit, helps to lengthen the smokes'route without implying a great room occupation.

In particular contingent situations, the second unit may be superfluous.

The water circulation inside the unit acts too as depuring member according two ways: the chemical way according to which the water, by combining with the gaseous substances existing in the smokes (carbon monoxide, carbon dioxide, nitrogen oxides, etc.) dissolves them and absorbs them, then eliminating them; the mechanical way according to which the water increases the weight of the greatest particles, thus making the deposit thereof easier.

The water contributes in dropping the smokes' temperature, by making them arriving cool at the last treatment stage. It is to be meant, however, that the water can be changed, whenever it contains several impurities, by emptying the tank 48 and filling-up it through the feeding duct 49.

A control system, connected to means for measuring the temperature, could drive the first circulation pump 50 and also the second one, as well as the refrigerating means 53, to keep the smokes'temperature below a prefixed level at time of expulsion.

Once arrived at the third filtering chamber 29, the smokes are cool by this time and carry only very fine particles which are trapped in the following chambers, wherein the filtering material has an increasing compactness.

It is to be noted that all the parts may be disassembled, cleaned, replaced, assembled again quite easily; the

various plates may be fastened by bolts or similar screw- like members or even members with reversible fixed ends.

The seal may be guaranteed by inserting rubber strips, silicone rubber in particular, in appropriate areas.

The filtering material may be washed and re-activated, if this may be more convenient than the replacement. The refrigerating system may be fed by simple running water.

To avoid possible black-outs, the system may include an uninterruptible power supply and a special inverter to keep the system working until the fireplace is wholly burnt-out.

To the above described suction system a person skilled in the art, in order to satisfy additional and contingent needs, can introduce several additional modifications and variants, all however within the protective. scope of the present invention, as defined by the enclosed claims.