Untitled record

64) Agent: Cabinet Lavoix, 2, place d'Estienne-d'Orves, 75441 Paris Cedex 09.

Extractor hood improved to capture and evacuate gases or other.

Invention of:

331 (32) (31

Con ventional priority:

(61) References to the main patent: Invention patent no. 71.43831 dated December 7, 1971. (60) Certificate of previous addition (s):

Sale of booklets at IMPRIMERIE NATIONALE, 27, rue de la Convention - 75732 PARIS CEDEX 15

The present invention relates to extractor hoods used to capture and evacuate gases, fumes or the like, emitted by any source, of the type comprising a closed chamber and comprising means for evacuating said fumes or others the outlet of which is channeled to the outside of the hood, directly or through a filter.

The extractor hood described in the main patent includes distribution means suitable for emitting an air curtain surrounding the source of emission of the fumes and directed from top to bottom.

In some cases, it may be advantageous to use a vertical air curtain surrounding said source and directed from bottom to top.

In addition, in many modern construction buil dings, there is now a general suction system serving the premises and intended to provide ventilation for hygienic installations, kitchens, clothes dryers or the like.

The invention therefore relates to an extractor hood of the type described in the main patent, characterized in that said exhaust means are constituted by a suction turbine driven by a motor and disposed in a central opening in the bottom wall of the hood and supplying said distribution means, these distribution means: being constituted by a perforated ramp arranged around said source, connected to the chamber by a pipe, -Te flow of the turbine putting said chamber under pressure and the section of said channeled outlet comprising adjustment means so that a curtain of air is blown from bottom to top through the holes in the ramp.

According to another embodiment, the hood is suitable for use in a building comprising a general suction installation, said evacuation means are connected directly to said installation and the distribution means are supplied by a turbine arranged in an opening from the top wall of the hood.

In this embodiment, the distribution means can be constituted by holes provided in the periphery of the lower wall of the hood.

In a variant, they can consist of a perforated ramp around the source of the fumes to be captured and connected to the hood by an appropriate pipe.

In another embodiment, the evacuation means are constituted by a first turbine disposed in an opening in the lower wall of the hood, this turbine being isolated from the closed chamber, inside the latter and its outlet being channeled outwards, the distribution means being constituted by a perforated ramp surrounding the source of the fumes to be captured, connected to the closed chamber and these means being supplied by a second turbine arranged in an opening in the upper wall of the hood, the two turbines can be fixed to the opposite ends of the shaft of a single motor.

Other characteristics of the invention will appear during the description which follows, made with reference to the appended drawings given solely by way of example and in which 'FIG. 1 is a side sectional view of an extractor hood according to the invention, showing a stove arranged under the hood and the air curtain emitted from bottom to top by a ramp arranged around the stove;

The Tig. 2 is a view similar to that of FIG. 1, a hood comprising a second turbine for supplying the distribution means;

Fig. 3 is a view of an extractor hood suitable for use in a building comprising a general suction installation;

Fig. 4 is a view similar to that of FIG. 3 of a variant.

According to the example of execution shown in FIG. 1, the hood 1 is arranged above a stove.

It includes a closed interior chamber 2, {rear wall 3, having an outlet orifice 4, and adapted to be fixed against a wall 5. A register 6 of conventional type being disposed in the outlet orifice 4 in order to allow adjust the section of it.

A turbine 7 driven by a motor 8 is disposed in an opening 9 in the lower wall of the hood and in which a filter 10 can be provided.

The distribution means are constituted by a pipe 11, having an appropriate section, which is connected to the chamber 2 and extends downwards to a point situated a little below the upper part of the cooker 12 above. of which the hood 1 is disposed, and by a ramp 13, which can be closed by an extension of the pipe 11 bent and appropriately perforated, extending horizontally around the stove 12.

In service, the air sucked in by the turbine 7 puts the chamber 2 under overpressure thanks to an appropriate adjustment of the section of the port 4 by means of the damper 6.

Consequently, a part of the gases sucked in by the turbine escapes through the orifice 4 while the rest feeds the ramp 13, via the line 12, the ramp comprising suitable perforations and / or nozzles (not shown) to emit an air curtain 14 from bottom to top towards the hood, this curtain channeling the fumes to be captured 16 and preventing them from spreading into the atmosphere.

Fig. 2 shows a variant of the hood shown in FIG. 1 in which the distribution means, also formed by a ramp 13a connected to the chamber 2a by a line 11a, are supplied by a second turbine, designated by the reference 17 which can be fixed on the shaft of the motor 8a, at l end thereof which is remote from the turbine 7a.

In this variant, the turbine 7a is enclosed in a casing 18 which constitutes the support for the motor 8a and isolates it from the chamber 2a, and which is extended by an outlet pipe 19 connected directly to the outlet orifice 4 of the hood, thus constituting the means of evacuation thereof.

Turbine 17 draws air outside the hood

25) towards the chamber 2a and thus feeds the distribution means 11a, 13a, while the gases 16 sucked in by the turbine 7a are discharged directly with the air from the curtain 14a, the flow rates of the two turbines being adjusted appropriately to the means of rheostats, in a conventional manner.

3θ We have shown in Figs. 3 and 4 two embodiments of extractor hoods according to the invention, suitable for use in buildings comprising a general installation of suction.

In this case, the evacuation means consist of · a pipe 20 which directly connects the opening 21 of the lower wall of the hood to the outlet orifice 40 isolate this opening from the chamber 22, the means of distribution being fed by a turbine 27 disposed in an opening in the upper wall of the hood.

In the example of FIG. 3, the distribution means consist of a series of holes 28 drilled in the periphery of the lower wall of the hood.

In the example shown in FIG. 4, the distribution means consist of a pipe 29 connecting the closed chamber 22 to a ramp, (not shown).