Displacement conditioners are well known to the art and will not therefore be further discussed herein.

The displacement system is particularly suitable to operate in environments where telecommunications systems are installed, in Data Processing Centres, in electrical panel rooms and so forth, namely in environments (like those diagrammatically illustrated in Figures 2,3 and 5) characterised by the presence of cabinets (or"racks") containing apparatus with a high thermal load.

Equally known to those skilled in the art is the"attached air jet"air distribution, illustrated diagrammatically in Figure 1, which is obtained by introducing air through an aperture A positioned so that the air jet V moves along a surface S to which said air jet V tends to adhere.

"Attached air jet"air distribution is normally used in ceiling diffusers to distribute air into the environment.

In the environments characterised by the presence of cabinets (or racks) containing apparatus with a high thermal load, a displacement system works very well provided some installation conditions are respected but unfortunately these conditions are not always reproducible in reality.

Figure 2 shows a plan view of a room in which there is an ideal situation: the conditioners CO are placed in front of the corridors C between the rows of racks (only the first of which is indicated by A in Figures 2,3, 5 for the sake of simplicity of the graphic representation) where there are the air inlets of the racks themselves at a distance between the front of the conditioner CO and the front of the rows of racks as to allow the air flow F to be distributed perfectly according to the displacement system along the rows

of racks.

Actual operating conditions normally differ from the ideal conditions shown in Figure 2 because (for reasons of space inside the room) the rows of racks are generally too close to each other and/or to the conditioners CO and/or because the conditioners CO are wider then corridor C where they have to introduce the air.

In this case (shown diagrammatically in Figure 3) a part F of the air emitted by the conditioners CO enters the corridors C in which there are the air inlets of the racks; a part F'of the air strikes the racks losing the effect caused by the displacement, rises and tends to be sucked in again by the fan of the conditioner CO before reaching the racks; a part F"of the air enters the corridors C"between the rows of racks where there are no air inlets to the racks and is (practically) useless for the purposes of conditioning.

The conditioning system no longer works well and the performance can deteriorate.

As shown in Figure 3, only the part F of the air flow leaving the conditioners CO is distributed correctly in the room, whereas most of the flow is reabsorbed into the conditioner CO (part F') or does not contribute to conditioning (part F").

Object of the present invention is a conditioner, in particular a displacement conditioner, comprising means designed to distribute air in an"attached air jet"manner.

Said conditioner presents the characterising elements illustrated in claim 1; further advantageous characteristics of the invention form the subject matter of the dependent claims.

An exemplary embodiment of the invention will now be described, by way of non- limiting illustration, with reference to the appended figures, in which: - Figure 1 shows diagrammatically an"attached air jet"air distribution, - Figure 2 shows diagrammatically a plan view of a room in which the displacement conditioners operate in ideal conditions; - Figure 3 shows diagrammatically a plan view of a room in which the displacement conditioners operate in actual conditions; -Figure 4 shows diagrammatically a perspective, partially sectioned view of the bottom part of a displacement conditioner modified according to the invention;

- Figure 5 shows diagrammatically the plan view of a room in which displacement conditioners modified according to the invention operate in real conditions.

In the appended figures like elements are identified by the same alphabetical reference letters.

As stated above, Figure 1 shows-very diagrammatically-an"attached air jet"air distribution, Figure 2 shows diagrammatically a plan view of a room in which the displacement conditioners CO operate in ideal conditions and Figure 3 diagrammatically shows a plan view of a room in which the displacement air conditioners CO operate in actual conditions with performances that are often far inferior to those that can be obtained in ideal conditions.

Figure 4 shows diagrammatically a perspective, partially sectioned view of the bottom part of a displacement conditioner CO-modified according to the invention- comprising means designed to distribute air in an"attached air jet"manner, wherein said means consist of a series of nozzles U, formed in the base B of the displacement conditioner CO, which create"attached air jets"designed to draw by induction the flow of air leaving the displacement conditioner CO and direct it into the corridor C where the air inlets of the racks are situated.

Each of the nozzles U formed in the base B of the displacement conditioner CO can be occluded by means of per se known removable means and in any case in a manner obvious to a person skilled in the art.

Only a minimal percentage (preferably less than 15%) of the air handled by the conditioner CO is passed-at a sufficiently high speed to create an"attached air jet"-in the nozzles U.

The speed of the air flow leaving the nozzles U can be determined on a case-by-case basis by a person skilled in the art on the basis of his own experience (and in any case without having to perform inventive activity) to respond to a specific requirement.

The rest of the air handled by the conditioner CO exits from the displacement distribution grilles indicated by G in Figure 4 and not described herein because they are per se known.

Further structural elements of the conditioner CO, diagrammatically indicated by EC in Figure 4, will not be described because they are per se known and in any case they are outside the scope of the present invention.

Figure 5 shows diagrammatically a plan view of a room in which displacement conditioners CO, modified according to the invention, operate in actual conditions.

When the nozzles U which are not situated to coincide with the corridors C in which the flow of air leaving the conditioner CO is intended to be channelled are occluded, the air flows FU leaving the unoccluded nozzles U form"attached air jets"at floor level able to draw by induction the air flows F exiting the grilles G for displacement diffusion into the corridors C, preventing them from striking the rows of racks (as happens to the air flows F'of Figure 3) and/or from being channelled into the corridors C', as happens to the air flows F"in Figure 3.

The"attached air jet"air flows FU leaving the unoccluded nozzles U therefore convey the flow of air leaving the grilles G into the corridors C between the rows of racks where the air inlets of the racks are situated, optimising (or at least improving) the efficiency of the conditioner CO.

Without departing from the scope of the invention, a person skilled in the art can make to the apparatus previously described all changes and improvements suggested by normal experience and/or by the natural evolution of the art.