ES2777923A1 - EXTRACTOR ASSEMBLY TO BE INSTALLED INSERTED IN A DUCT OF AIR (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

Extractor assembly to be installed inserted in an air duct, comprising an impeller (1); an actuator element (2) for providing a rotational impulse on the impeller (1); a support (3); and, a casing (4) to externally wrap the impeller (1), the actuator element (2) and the support (3). The support (3) comprises an internal wall (3.3) that with the first face (3.1) determines a housing (6) to house the actuator element (2); and an external wall (3.4), which is arranged radially and externally with respect to the internal wall (3.3), so that these walls (3.3, 3.4) define a passage (7) for displacement of the air. With the extractor assembly ready for use, the external wall (3.3) partially wraps radially and internally the casing (4), so that the casing (4) is free from contact with the air driven by the impeller (1) in correspondence with the external wall (3.4). (Machine-translation by Google Translate, not legally binding)

Description

DESCRIPTION

EXTRACTOR ASSEMBLY TO BE INSTALLED INSERTED IN A DUCT

OF AIR

Technical sector

The present invention is related to the industry dedicated to extractor assemblies to be installed interspersed in air ducts.

State of the art

At present, extractor assemblies are widely known to be installed interspersed in air ducts. These extractor assemblies have an impeller with blades, an electric motor to rotate the impeller so that, by means of the vanes, an air flow or displacement is generated, a support to fix the motor inside the extractor assembly and a casing external as a general envelope.

Said extractor assemblies, as a consequence of the generation of said air flow or displacement, generate annoying noise. Mainly, this noise is generated as a consequence of air displacement along the extractor assemblies.

In turn, this is largely due to the fact that the air is not displaced in a completely continuous or uniform manner, but is generated with discontinuities that derive in point contacts according to a mainly irregular frequency with the external casing. This drawback is seriously aggravated in the case of metallic external housings.

In view of the described disadvantages or limitations that presently existing solutions present, a solution is necessary that allows reducing the noise generated by the passage of air along the extractor assembly.

Object of the invention

In order to meet this objective and solve the technical problems discussed so far, in addition to providing additional advantages that may be derived later, the present invention provides an extractor assembly to be installed interleaved in an air duct.

The extractor assembly comprises an impeller having a base and blades, the blades projecting from the base, in addition to being able to additionally have a panel to prevent air contact with the casing in correspondence with the blades.

The extractor assembly further comprises an actuator element to provide a rotational impulse in the impeller so as to generate an air flow through the blades; a support having a first face and a second face, the first face being for fixed arrangement of the actuator element; and, a housing comprising a first part and a second part for externally wrapping the impeller, the actuator element and the support.

The support comprises an internal wall that with the first face determines a housing to house the actuator element; and an external wall, which is arranged radially and externally with respect to the internal wall, such that these walls define a passage for displacement of the air.

Thus, with the extractor assembly ready for use, the external wall contacts radially and internally against the first part and the second part, as well as against a joint area of the first part and the second part with each other, so that it remains blocked an air outlet in correspondence with the external wall. In this way, a noise outlet through said junction area is also blocked.

Preferably, the outer wall is arranged in contact against the entire joint area. Said joining zone, for its part, is preferably formed by an overlap between the first part and the second part.

Preferably, the support comprises fins in the passage to direct the air flow. Accordingly, the fins are preferably curved to eliminate a tangential component of the air flow generated by the blades so that the air flow is steerable according to a rectilinear path.

With the actuator element fixedly arranged on the support and the impeller attached to the actuator element, between the base and the internal wall there is a gap for an air inlet to the actuator element.

The extractor assembly can comprise a cover arranged in correspondence with the second face of the support so as to determine a continuation of the passage. Accordingly, the cover preferably has a concave side for enveloping components of the extractor assembly and a convex side for conducting air.

The extractor assembly may comprise a conduit arranged communicating an external part of the casing with the housing. Accordingly, the conduit preferably has a first section externally projecting with respect to the external wall and each of the parts of the casing has a groove to jointly define a reception gap for the first section.

The extractor assembly may comprise a locking element arranged to prevent an air movement between the casing and the impeller panel, so that the air entering the casing is conducted between the panel and the base.

Preferably the housing comprises a metallic material. Additionally or alternatively, preferably the support comprises a plastic material. Additionally or alternatively to any of the above, preferably the impeller comprises a plastic material.

Description of the figures

Figure 1 shows an extractor assembly belonging to the state of the art, upper part, and an extractor assembly object of the invention, lower part.

Figure 2 shows an exploded schematic view of an extractor assembly to be installed interspersed in an air duct, object of the invention.

Figures 3 and 4 show schematic perspective views of the extractor assembly, object of the invention.

Figures 5 and 7 show schematic side views of the extractor assembly, object of the invention; while figures 6 and 8 show a rear and front view, respectively.

Figure 9 shows a schematic view, according to a longitudinal section, of the extractor assembly in readiness for use.

Figures 10A and 10B show schematic views of an impeller comprised in the extractor assembly, object of the invention.

Figures 11 and 12 show schematic perspective views of a support included in the extractor assembly, object of the invention.

Figures 13 and 15 show rear and front schematic views of the support, respectively; while Figures 14 and 16 show a schematic side view and a schematic side sectional view of said support, respectively.

Detailed description of the invention

The present invention refers to an extractor assembly to be installed interspersed in an air duct, which comprises an impeller (1), an actuator element (2), a support (3) and a casing (4), the which comprises a first part (4.1) and a second part (4.2) to externally wrap the impeller (1), the actuator element (2) and the support (3) as a general envelope.

The impeller (1) has a base (1.1) and blades (1.2), the blades (1.2) being projected from the base (1.1). The base (1.1) has a contact face (1.1 ') configured to receive a contact from the air that enters the impeller (1), and therefore the extractor assembly. The impeller (1) is visible in Figures 2, 10A and 10B.

This configuration of the base (1) provides a direction to the internal periphery of the air extractor assembly, that is to say towards a radial and externally remote part with respect to an imaginary central longitudinal axis (X) of the extractor assembly, minimizing the impact or a impediment against the advance of air along the casing (4) by an internal part thereof. Accordingly, said contact face (1.1 ') has a convex shape.

The actuator element (2), for its part, is an electric motor arranged to provide a rotational impulse to the impeller (1) in such a way that it generates an air flow through the blades (1.2). The actuator element (2) is visible in figures 2 and 9.

Accordingly, the impeller (1), and more specifically through the base (1.1), is arranged mechanically connected to the actuator element (2) to receive the rotation driven by it (2). Said air flow generated by the rotary movement of the blades (1.2) is displaced along the extractor assembly.

The support (3) has a first face (3.1) and a second face (3.2), the first face (3.1) being opposite the second face (3.2). The first face (3.1) is for a fixed arrangement of the actuator element (2). The support (3) is visible in figures 11 to 16.

The actuator element (2) is fixedly arranged on said first face (3.1) of the support (3) by means of threaded joints. Likewise, preferably, between the actuator element (2) and said first face (3.1) a shock absorber or vibration absorbing element (5) is arranged. Accordingly, the fixed connection of the actuator element (2) on the first face (3.1) is through being fixed to the damper (5), which in turn is arranged fixed to said first face (3.1) for the use of the extractor assembly.

The support (3), on the one hand, additionally has an internal wall (3.3) perpendicular, or substantially perpendicular, to the first fixing face (3.1) of the actuator element (2). Preferably, the internal wall (3.3) extends parallel to the imaginary central longitudinal axis (X) of the extractor assembly. Likewise, preferably, said internal wall (3.3) describes a geometric shape, preferably cylindrical, so that it determines a housing (6).

The first face (3.1) of the support (3) is peripherally limited by said internal wall (3.3). In this way, the housing (6) is defined radially and externally or perimeter by the internal wall (3.3) and axially or longitudinally by the first face (3.1).

Said housing (6) has an opening at a longitudinal end opposite the location of the first face (3.1) through which the actuator element (2) projects at its junction with the impeller (1), that is, the internal wall ( 3.3) and the first face (3.1) determine the housing (6), this (6) being open.

The support (3), on the other hand, additionally has an external wall (3.4) which is arranged radially and externally with respect to the internal wall (3.3). Also, preferably, the external wall (3.4) describes a geometric shape, preferably cylindrical. Thus, preferably, said external wall (3.4) is parallel, or substantially parallel, to the internal wall (3.3). Accordingly, the inner wall (3.3) and the outer wall (3.4) are radially spaced from each other so as to define a passage (7) for air displacement.

The internal wall (3.3) and the external wall (3.4) are joined together by fins (3.5) included in the support (3). These fins (3.5), in addition to acting as a connecting element between both said walls (3.3, 3.4), act as directing elements of air or the air flow generated by the impeller (1), at the same time that they determine a space of step between them according to step (7).

Preferably, the fins (3.5) are curved. Said flow of air generated by the impeller (1), due to the rotation of the impeller (1), leaves it with a helical flow, that is, describing a spiral-shaped path. In other words, the air flow exiting the impeller (1) has a speed with a tangential component. Accordingly, the fins (3.5) are arranged to eliminate said tangential component so that the air is directed in a linear or rectilinear manner, the speed and pressure of the air being increased.

Preferably, the external wall (3.4) is smooth, continuous and uniform, that is to say lacking through holes in the radial direction. Likewise, also preferably, the internal wall (3.3) is equally smooth, continuous and uniform, that is to say lacking through holes in the radial direction.

The actuator element (2) being correspondingly fixed on the support (3) in correspondence with the housing (6) and the impeller (1) mechanically joined to the actuator element (2) to receive the rotational impulse provided by it (2) from shape that generates the air flow, the configuration and arrangement of the impeller (1) and of the external wall (3.4) are such that the air flow leaves the impeller (1) driven in such a way that it is directed in part substantially parallel to the wall external (3.4) and partly against said external wall (3.4).

By means of this configuration and arrangement, which can be derived from the view of figure 9, at least a greater part of the generated air flow is prevented from contacting the casing (4) both at the outlet of the impeller (1) and in its advance or displacement longitudinal and parallel to the imaginary central longitudinal axis (X) along the extractor assembly.

Preferably, through this configuration and arrangement, the proportion of the air flow generated that contacts the casing (4) at the outlet of the impeller (1) is zero, or at least negligible from the point of view of the sound decibels it generates. Likewise, the proportion of the air flow that can be generated that can contact the casing (4) in its longitudinal advance or displacement and parallel to the imaginary central longitudinal axis (X) along the extractor assembly is also zero, or at least negligible from the point view of the noise generated.

The base (1.1) of the impeller (1) has a flange or contour (1.1 '') which, the actuator element (2) being correspondingly fixed in the support (3) in correspondence with the housing (6) and the impeller (1 ) mechanically attached to the actuator element (2) to receive the rotational impulse provided by it (2) in such a way as to generate the air flow, it is aligned, or substantially aligned, with the internal wall (3.3) of the support (3). Additionally, said flange or contour (1.1 '') includes a longitudinal extension aligned with said internal wall (3.3)

Accordingly, between said contour (1.1 '') and a longitudinal end of the internal wall (3.3) there is a defined separation space (S) for a controlled entry of air to the housing (6). The gap (S) is therefore configured to provide cooling of the actuator element (2) through a controlled and reduced part of the air flow generated by the impeller (1).

The second face (3.2) of the support (3) is configured for the provision of additional components (8), which intervene in the operation of the extractor assembly. In figures 2 and 9 one of these components (8) is indicated, which is a capacitor.

The present extractor assembly comprises a cover (9) to be arranged, ready for use, in correspondence with the second face (3.2) of the support (3) in such a way which determines a continuation of step (7). Preferably, said cover (9) is arranged attached to the support (3) by means of threaded connections, although alternatively it can be by means of connection points by clipping or elastic jump.

On the one hand, the cover (9) is defined in such a way that it has a concave side to surround the components (8) of the extractor assembly arranged in correspondence with the second face (3.2) and a convex side to guide the air. Accordingly, said cover (9) has a perimeter edge (9.1) dimensioned so that it is equal to or less, in terms of a radial measure, than the geometric shape of the internal wall (3.3). See figure 9.

Preferably, the cover (9) is attached to the support (3) so that the perimeter edge (9.1) is arranged in such a way as to determine a continuation of the internal wall (3.3), according to the longitudinal direction and parallel to the imaginary central longitudinal axis (X) of the extractor assembly. Thus, the generation of turbulence in the air flow generated by the impeller (1) in its movement in correspondence with the end of the internal wall (3.3) according to the direction of movement or advance of said air flow is prevented. This arrangement or configuration is clearly visible in figure 9.

On the other hand, the cover (9) is defined such that it has a convex side to conduct the air. That is, it smoothes the directing of the air flow after its advance through the passage (7) towards a more radial and internal zone to exit the extractor assembly.

Accordingly, said coverage (9) has a curved edge (9.2) on said convex side dimensioned in such a way as to determine a reduction of the radial measure, or with respect to said imaginary central longitudinal axis (X), of the coverage ( 9) in a progressive way, that is to say, devoid of brusqueness. In this way, the cover (9) prevents the formation of turbulence or pressure changes that hinder or reduce the fluidity of the air when leaving the extractor assembly, or at least in its direction towards a more radial and internal zone after its advance through step (7) to exit the extractor assembly.

As previously mentioned, the casing (4) comprises the first part (4.1) and the second part (4.2). Preferably, said parts (4.1, 4.2) are available joined together, each determining a longitudinal end of the extractor assembly, as is clearly seen, for example, in figure 2, although alternatively they can be available joined together, each determining a longitudinal half of said set.

The first part (4.1) and the second part (4.2) are joined together, according to a joining zone (U) located in correspondence with the external wall (3.4). More specifically, the external wall (3.4) is arranged in contact with the first part (4.1) and with the second part (4.2), both in proximity to the junction area (U) between the two and in correspondence with the area of union (U), which is formed by an overlap between said parts (4.1,4.2).

According to the aforementioned preferred option according to which each of the parts (4.1, 4.2) determines one of the longitudinal ends of the extractor assembly, the joint zone (U) is located completely in correspondence and in contact with the external wall (3.4), that is to say in its entirety, as can be derived from figures 2 and 9. In this way, it contributes to a watertight union or sealing between the aforementioned parts (4.1,4.2) of the casing (4) in such a way that an air leakage or exit through said junction zone (U) is prevented.

The first part (4.1) and the second part (4.2) have a first step (4.1 ', 4.2') in a longitudinal part parallel, or substantially parallel, to the imaginary central longitudinal axis (X) for longitudinally adjusted arrangement of the outer wall (3.4). Additionally, said first steps (4.1 ', 4.2') are defined so that an internal face, opposite to that in contact with the casing (4), of the external wall (3.4) is aligned or gives continuity to an internal surface of the casing (4), that is to say the parts (4.1, 4.2). See figure 9.

Thus, the generation of turbulence in the air flow generated by the impeller (1) in its movement in correspondence with both the beginning of the external wall (3.4) and the end of said wall (3.4) is prevented according to the direction of displacement or advance of said air flow.

Additionally, one of the parts (4.1, 4.2) has a second step (10) to overlap the corresponding longitudinal end of the other part (4.2, 4.1) in order to improve the sealing, that is to say to prevent the escape of air and noise. In this case, the one junction zone (U) is determined or defined according to this overlap, as has also been previously described.

The casing (4) has an inlet mouth (11) and an outlet mouth (12).

one

Preferably, the inlet mouth (11) is located entirely in the first part (4.1) and the outlet mouth (12) is located in its entirety in the second part (4.2). Likewise, the inlet mouth (11) determines the entry of the air sucked into the extractor assembly by the impeller (1) and the outlet mouth (12) determines the output of the air flow driven or generated by the impeller (1) of the assembly extractor.

These openings (11, 12) are configured to be connected to an air duct, not the object of the present invention. Likewise, the parts (4.1,4.2) of the casing (4) have smaller dimensions in said openings (11, 12), that is to say a smaller internal diameter.

In this way, therefore, the casing (4) has diameter change sections (4 '). Accordingly, the casing (4) has one of the diameter change sections (4 ') immediately after the inlet mouth (10) and another of the diameter change sections (4') immediately before the outlet mouth (11), according to the direction of advance or displacement of the air flow generated by the impeller (1).

Optionally, the external wall (3.4) of the support (3) extends so that it radially and internally surrounds the casing (4) also in correspondence with the diameter change section (4 ') located immediately before the outlet mouth ( 12).

In correspondence with each of the openings (11, 12), radially and externally to these (11, 12), the extractor assembly comprises a gasket (13) to provide a seal so as to prevent an air leak with respect to the air duct and the extractor assembly itself.

With the extractor assembly mounted, or at least the parts (4.1, 4.2) of the casing (4) joined together according to the joining zone (U) in correspondence on the external wall (3.4) of the support (3), the openings (11, 12) are arranged concentric with respect to the imaginary central longitudinal axis (X) and according to a smaller diameter with respect to said external wall (3.4), in addition to preferably with respect to internal wall (3.3) . In this way, both the entry of air to the extractor assembly and the exit of air from it are favored.

Preferably, and as can be clearly seen in Figures 10A and 10B, the impeller (1) additionally has a panel (1.3). This panel (1.3) has an extension in the longitudinal direction so that at each point along it it corresponds to a different diametrical measure. That is, the panel (1.3) has open longitudinal ends, each of these with a different diameter from the other according to a preferably progressive variation.

The open longitudinal end arranged opposite the inlet mouth (11) has a smaller diameter than the open longitudinal end arranged opposite the actuator element (2). According to a progressive, and preferably linear, change in the diameter of said panel (1.3), this (1.3) is configured to be arranged parallel, or substantially parallel, to the casing (4) in correspondence with the section of diameter change (4 ') corresponding.

Being the extractor assembly mounted, for example according to the appreciable state in figure 9, said panel (1.3) prevents or blocks the air from contacting the casing (4), and more specifically with the diameter change section (4 ') located immediately after the inlet mouth (11).

This panel (1.3) is highly efficient, reducing the noise generated by the extractor assembly in operation due to the fact that it avoids the contact of the air with the casing (4) in a critical zone, since it deals with the impeller's actuation zone ( 1), which is the area in which, on the one hand, the air suction is generated and, on the other hand, the air flow to be displaced or driven along the extractor assembly.

In order to optimize the air inlet to the impeller (1) through the open longitudinal end arranged opposite the inlet mouth (11), the diameter of said open longitudinal end is equal to or greater, preferably greater, than the diameter of the inlet mouth (11).

In order to further optimize the air inlet to the impeller (1) through the open longitudinal end arranged opposite the inlet mouth (11), the extractor assembly preferably comprises a blocking element (14). The blocking element (14), visible in figure 9, is arranged blocking an air passageway between the casing (4) and the panel (1.3) of the impeller (1) at the entrance of said air to the extractor assembly, and more specifically to the impeller (1).

Accordingly, said blocking element (14) is arranged attached to the casing (4), by an internal part thereof, as can be seen in said figure 9. Thus, the blocking element (14) forces so that the air that enters the extractor assembly through the inlet mouth (11) enters the impeller (1). Said blocking element (14) is arranged immobile, which favors the non-generation of noise.

Additionally, and preferably, the locking element (14) is fixed in the casing (4), in addition to being partially inserted in the impeller (1) through the open longitudinal end arranged opposite the inlet mouth (11) . See again the aforementioned figure 9.

The open longitudinal end of the panel (1.3) of greater diameter, the one arranged opposite the actuator element (2), has a diameter greater than a diameter of the flange (1.1 '') of the base (1.1), as well as greater than a diameter of the longitudinal extension aligned with the internal wall (3.3). These diameters are considered based on radii with respect to the imaginary central longitudinal axis (X) of the extractor assembly.

In this way, a fluid path, smoother, is provided for the air driven by the blades (1.2) at their outlet by providing between the base (1.1) and the panel (1.3) of the impeller (1) a separation according to with the described difference in diameters. Thus, therefore, the path is more parallel to the imaginary central longitudinal axis (X) of the extractor assembly, with fewer direction changes, and the existing direction changes are also less abrupt. See arrows included in the extractor assemblies in figure 1.

This configuration, in addition to providing less noise, provides smaller diametral dimensions of the extractor assembly for certain characteristics of the impeller (1), such as flow and pressure. This makes it possible to install the extractor assembly in smaller spaces than in other cases according to said characteristics of the impeller (1). See, for example, figure 1, which shows a longitudinal section view of the present assembly (lower part) and a view of a conventional extractor assembly (upper part), according to the same flow and pressure performance.

The present extractor assembly comprises a conduit (15) arranged communicating a

one

external part of the casing (4), and therefore of the extractor assembly, with the housing (6). In this way, the conduit (15) acts as a passage element for a wiring to electrically connect an electrical box (16), included in the extractor assembly and arranged on the outside of the casing (4) for accessibility, with the actuator element (2). This conduction (15) is appreciable in figure 16.

Said conduit (15) has a first section (15.1) externally in projection with respect to the external wall (3.4). Additionally, the conduit (15) has a second section (15.2) which extends through the passage (7) so that it reaches the housing (6).

Accordingly, each of said parts (4.1,4.2) of the casing (4) has a slot (17) open at one end to receive said first section (15.1) of the conduit (15) so that together both Said parts (4.1, 4.2), and more specifically both said slot (17), surround or surround the first section (15.1). In this way, said first section (15.1) acts as an unequivocal positioning element of the parts (4.1,4.2) of the casing (4) relative to each other.

According to a preferred embodiment of the invention, the present extractor assembly is for installation in aggressive environments, which regulations require that the casing (4) be metallic. These environments, by regulations, require the extractor assembly to be resistant to impacts, fire, etc. In accordance with this, the elements, their configuration and their arrangement take on special relevance in order to provide an efficient and notable reduction of the noise generated by the use of the extractor assembly.

According to this described preferred embodiment, the support (3) is preferably made of a plastic material to reduce the total weight of the extractor assembly.

Continuing with the described preferred embodiment, the impeller (1) is preferably made of a plastic material to, among other reasons, reduce the total weight of the extractor assembly, reduce the noise generated in the generation of the air flow to be propelled towards the mouth of the outlet (12) and increase the performance of the extractor assembly due, on the one hand, to the reduced weight of being made of a plastic material instead of a metallic material and, on the other hand, to a specific geometry proportional to the blades ( 1.2) as it is made of plastic and not metal, obviously within limited manufacturing times and costs.

Claims (15)

1 Extractor set to be installed inserted in an air duct, the extractor set comprising: - an impeller (1) having a base (1.1) and blades (1.2), the blades (1.2) projecting from the base (1.1); - an actuator element (2) to provide a rotational impulse on the impeller (1) so as to generate an air flow through the blades (1.2); - a support (3) having a first face (3.1) and a second face (3.2), the first face (3.1) being for a fixed arrangement of the actuator element (2); - a casing (4) comprising a first part (4.1) and a second part (4.2) for externally wrapping the impeller (1), the actuating element (2) and the support (3); characterized in that the support (3) comprises: - an internal wall (3.3) that with the first face (3.1) determines a housing (6) to house the actuator element (2); and - an external wall (3.4), which is arranged radially and externally with respect to the internal wall (3.3), so that these walls (3.3, 3.4) define a passage (7) for displacement of the air; where, with the extractor assembly ready for use, the external wall (3.4) contacts radially and internally against the first part (4.1) and the second part (4.2), as well as against a joining zone (U) of the first part (4.1) and the second part (4.2) to each other, so that an air outlet is blocked in correspondence with the external wall (3.4). 2. - Extractor assembly according to claim 1, characterized in that the external wall (3.4) is arranged in contact against the entire joint area (U). 3. - Extractor assembly according to claim 1 or 2, characterized in that the joining area (U) is formed by an overlap between the first part (4.1) and the second part (4.2). 4. - Extractor assembly according to any one of claims 1 to 3, characterized in that the support (3) comprises fins (3.5) in the passage (7) to direct the air flow. 5. - Extractor assembly according to claim 4, characterized in that the fins (3.5) are curved to eliminate a tangential component of the air flow generated by the blades (1.2) so that the air flow is steerable according to a rectilinear path. 6. - Extractor assembly according to any one of claims 1 to 4, characterized in that, being the actuator element (2) arranged fixed on the support (3) and the impeller (1) attached to the actuator element (2), between the base (1.1) and the internal wall (3.3) has a gap (S) for an air inlet to the actuator element (2). 7. - Extractor assembly according to any one of claims 1 to 5, characterized in that it additionally comprises a cover (9) arranged in correspondence with the second face (3.2) of the support (3) so that it determines a continuation of the step (7 ). 8. - Extractor assembly according to claim 7, characterized in that the cover (9) has a concave side to wrap components (8) of the extractor assembly and a convex side to conduct the air. 9. - Extractor assembly according to any one of claims 1 to 8, characterized in that it additionally comprises a conduit (15) arranged communicating an external part of the casing (4) with the housing (6). 10. - Extractor assembly according to claim 9, characterized in that the conduit (15) has a first section (15.1) externally in projection with respect to the external wall (3.4) and each of the parts (4.1, 4.2) of the casing (4) has a groove (17) to jointly define a reception gap of the first section (15.1). 11. - Extractor assembly according to any one of claims 1 to 10, characterized in that the impeller (1) additionally has a panel (1.3) to prevent air contact with the casing (4) in correspondence with the blades (1.2) . 12. - Extractor assembly according to claim 11, characterized in that it additionally comprises a blocking element (14) arranged to prevent an air movement between the casing (4) and the panel (1.3), so that the air entering the casing (4) is led between the panel (1.3) and the base (1.1). 13. - Extractor assembly according to any one of claims 1 to 12, characterized one because the casing (4) comprises a metallic material. 14. - Extractor assembly according to any one of claims 1 to 13, characterized in that the support (3) comprises a plastic material. 15. - Extractor assembly according to any one of claims 1 to 14, characterized in that the impeller (1) comprises a plastic material.