SUCTION DEVICE

Description

[0001] The present invention relates to a device in casings for sucking air containing impurities away from a region, such as a working place, for example at a kitchen grate, under or near the casing, said device comprising a casing downwardly open, at least a suction opening connected to a suction member for generating an air flow from below, into the casing and out through the suction opening for conducting air away from the device, means for conducting a part of the air sucked from the interior of the casing back to the region of a lower edge of a side wall of the casing and members for directing this air as a stream from said edge towards the interior of the casing, so that secondary air flows into the casing are induced at its edge region.

[0002] In the following such devices will be discussed in connection with cooking, i.e. so called kitchen grate casings, but it is emphasized that such devices as well as the device according to the invention are useful at every type of working place and the like, where the air contains particles which are unhealthy or irritating to inhale.

[0003] The object of devices of this kind is to remove as great a part of the impurities as possible in sucking such a small total air quantity as possible away from the region under the device. In particular, it is desired to suck air containing impurities away from the region beside the casing and in the edge regions of the casing without utilizing any enormous suction powers, which give rise to disagreeable draught, noise or removing of a great amount of clean and heated air, which would be very expensive.

[0004] Through the Swedish patent application published as SE-B-468684 (8601636-7) a kitchen grate casing is already known, in which outdoor air is conducted to the region of the lower edge of one of the side walls of the casing and is blown in a stream upwardly/inwardly in the casing towards a main suction opening, through which contaminated air is sucked into the casing and removed through an exhaust air system. The air stream draws through the so called ejector effect air containing impurities into the casing in the edge regions of the casing, by which no high suction power is required for sucking such air into the casing. However, the cold air in said air stream may give rise to so called cold fall phenomena inside the casing, and the total amount of air which has to be sucked away gets larger than if it were possible to recirculate a part of the air sucked and use this to form the air stream for the ejector effect. Devices being successful in this respect are known through US patent 4 050 367 and GB-A-2 169 697. The efficiency of these known devices is good, but could be further improved.

SUMMARY OF THE INVENTION

[0005] The object of the present invention is to improve a device of the type mentioned in the introduction, so that the quotient amount of impurities divided by the total amount of air sucked away will be even higher than in the devices of the kind already known.

[0006] According to the invention this object is obtained by a device which is provided with the characteristics defined in the characterizing part of the appended claim 1.

[0007] Thanks to the separate suction opening for producing the air stream at the lower edge of the side wall and the high position of this opening closer to the side wall than to the first main suction opening, it it possible to raise the air flows inside the casing, by which additional air may be drawn into the casing.

[0008] Additional advantages and characteristics appear from the detailed description of the embodiments of the invention as well as the appended claims, in which claim 5 defines a particularly advantageous embodiment, which realize the production of rotating secondary air flows inside the casing, which effectively retain contamination particles within the casing.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] With reference to the appended drawings, below follows a specific description of three preferred embodiments according to the invention cited as examples.

[0010] In the drawings:

Fig 1 is a schematic cross section view of a first embodiment of the device according to the invention,

Fig 2 is a view corresponding to Fig 1 of a second embodiment of the invention,

Fig 3 is a perspective view of an insert used in the device according to Fig 2, in which some portions are broken away for illustrating the construction of the insert, and

Fig 4 is a view corresponding to the views according to Figs 1 and 2 of a third preferred embodiment of the device according to the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

[0011] The device according to the invention shown in the figures will here be called kitchen grate casing, which is not to be understood as limitative. The parts common to the different embodiments have been provided with the same reference numerals.

[0012] The kitchen grate casing shown in Fig 1 comprises a substantially box-shaped casing 1 downwardly open. The kitchen grate casing has mirror image symmetry with a vertical mirror image symmetry plane extending in the longitudinal direction of the casing 1, i.e. perpendicularly to the drawing plane. A V-shaped filter house 2 projects downwardly from the upper limitation of the casing and towards the casing opening 3 in the middle of the casing. The filter house 2 is elongate and extends parallel to the side walls 4 of the casing over substantially the entire length of the casing. The filter house 2 is provided with first suction openings 6 covered by filters 5 absorbing smell and other impurities. The filters 5 are disc-like and constituted by conventional filter elements adapted for the particular task. At the top the filter house is terminated by an evacuating opening 8 covered by a filter 7 to an exhaust air conduit 9 connected to a suction member, for example the main fan of the main ventilation system of the premises or the building in question.

[0013] A second suction opening 10 is arranged in the upper limitation wall of the casing on each side of the V-shaped filter house 2. This suction opening is also covered by a filter 11 of the type similar to the type of the filters 5 and 7 and it is directed substantially vertically downwardly towards the opening of the casing. The second suction opening 10 is connected to a second suction member in the form of a fan 12 through an intake 13. The outlet 14 of the fan emerges into a distributing chamber 15 extending over substantially the entire length of the side wall 4. The distribution chamber has three elongate limitation walls, two of which are the side wall 4 of the casing and the upper limitation wall thereof and these are interconnected by means of an inclined wall 16. The inclined wall 16 is provided with a succession of openings 17 extending over substantially the whole length of the wall, a section according to Fig 1 being carried out through such an opening. A directing plate 18 is arranged on the inclined wall 16 outside the distribution chamber so as to divert and direct air coming out of the openings 17, so that it gives rise to air flows substantially being a tangent to the outside of the inclined wall 16.

[0014] The function of the kitchen grate casing just described is the following: a negative pressure will be created in the filter house 2 by the suction member connected to the exhaust air conduit 9 and a primary air flow from below and into the casing towards the first suction openings 6 will be produced. This air flow is indicated by several arrows 19. By means of the sucking action of each fan 12 a part of the air flowing towards the suction opening 9 will divert towards the second suction opening 10 (see arrow 20). The main part of this air passes through the filter 11, in which the greatest part of its impurities is caught, whereupon this air is recirculated to the casing through the distribution chamber 15. Thanks to the width of the distribution chamber the comparatively concentrated air flow emanating from the fan 12 will be distributed substantially uniformly over the entire length of the chamber and flowing out of the openings 17 in the direction indicated by the arrow 21. Thus, in practice an air stream with the same width as the length of the side wall 4 is formed, but it has a comparatively small dimension in the direction perpendicular thereto. Owing to the fact that air flowing along a wall has a tendency to be attracted by the wall and follow this, an air stream along the side wall 4 downwards towards the lower edge of the casing is created. At the lower edge of the casing a directing plate 23 extending over substantially the entirety of this edge is so arranged that it diverts said air stream substantially in the direction towards the first suction opening 6 (arrows 24). The air stream from the lower edge 22 of the side wall 4 in the direction upwardly/inwardly towards the interior of the casing obtained through this arrangement will induce secondary air flows from the outside of the casing in the edge regions thereof and into the casing towards a first suction opening 6. The fact that an air stream draws surrounding air into secondary air flows is usually called the ejector effect. The arrows 25 indicates air flows into the casing produced by said ejector effect. Thanks to this it will be possible to suck air containing impurities and located in these regions into the casing without the necessity of creating a disproportionately low negative pressure in the filter house 2, with removing of enormous amounts of clean air.

[0015] Another advantage of this kitchen grate casing consists in that a part of the air diverted towards the suction opening 10 through the ejector effect of the air flowing out of the openings 17 will be additionally diverted (arrow 26) and drawn into and follow the air stream downwardly towards the edge 22. In this way additional air quantities will be joining the air stream (for example arrow 27) and a rotating air movement will be produced in the room of the casing between the edge 22, the opening 10 and the walls 16 and 4. These rotating air flows or streams are very advantageous, since they retain particles contained in the air inside the casing and also raise the air flows inside the casing in an effective way. Furthermore, they prevent effectively parts of the air stream flowing downwardly towards the edge 22 from disappearing out through the opening 3 of the casing.

[0016] A second advantageous embodiment of the device according to the invention is shown in Fig 2. In this embodiment the parts 10-18 of the kitchen grate casing according to Fig 1 have been replaced by an insert 28 manufactured in advance, which is shown more in detail in Fig 3. The insert is designed to be introduced into kitchen grate casings already existing and be retained by means of suitable retaining members, in order to be easily removed when this is desired, for example for cleaning purposes. Such an insert may be arranged in either the position according to Fig 2 or the one according to Fig 4. The insert has a second suction opening 10 covered by a flat filter 11. This suction opening is connected to a fan 12, which blows out air sucked in through the opening 9 into a distribution chamber 29. The distribution chamber 29 is divided into two halves by a finely perforated plate 30, through which the air from the fan 12 has to pass in order to reach the openings 31 in one end of the chamber towards the interior of the casing. The perforated plate 30 contributes additionally to a uniform distribution of the air stream reaching the openings 31 over all of the openings. It appears from Fig 3 what the openings look like and how they are arranged, said filter 11 being omitted in this figure. In the device according to Fig 2 an elongate directing plate 32 is so arranged in the proximity of the openings 31, that the air stream coming out of the insert is directed downwardly along the side wall of the casing and an air stream as well as rotating air movements similar to the ones in the device according to Fig 1 are created. The directing plate 32 is advantageously adjustable for adjustment of the direction of the air stream.

[0017] A further advantage of the rotating air flows and the air stream moving along the side wall 4 consists in the fact that, if the side wall is made of a material with a high thermal conductivity, a great part of the heat content of the air may be led away to the room outside the casing, so that the air carried away through the exhaust air conduit 9 has a slightly lower temperature than the rest of the air of the room.

[0018] It is shown in Fig 4 how an insert according to Fig 3 manufactured in advance has been arranged in a kitchen grate casing with the suction opening 10 substantially horizontally directed and the openings 31 located in the vicinity of the lower edge 22 of the side wall 4. This insert is provided with a directing plate 32' according to Fig 3, which is adjustable (the screw 33) and so directed that it together with a directing member 34 replacing the directing plate 23 directs the air stream from the openings upwardly/inwardly substantially towards the first suction opening 6. The insert 28 in Fig 4 is preferably kept in place by resting on a lower edge portion 35 of the casing and upper guiding members not shown projects downwardly from the top of the casing and retain the insert in lateral direction, so that the latter after removing a short wall of the casing may be pushed into the same along the side wall 4 or through the opening 3. In the device according to Fig 4 the air flows inside the casing are directed more upwardly thanks to the high location of the second suction opening 10.

[0019] The embodiments described above relate to casings intended to be located in a room with both side walls 4 out in the room, but in the case that the casing is to be placed close to or against a wall the device only consists of a half of the devices shown. It will then be cut off in the mirror image symmetry plane, where a wall for application on the room wall in question is arranged. Preferably, this wall will then limit the filter house from which the exhaust air conduit emanates.

[0020] The first suction member may be constituted by the main fan of the ventilation system of the building, but a separate fan may just as well be arranged for this task.

[0021] In the case that the casing would have an important longitudinal extension several second suction openings may be arranged one after the other along the extension of the casing and through separate fans lead air to a common distribution chamber.

[0022] The openings 17 and 31, respectively, could be one single continuous elongated slit, even though a plurality of holes would be advisable from the stability point of view.

[0023] The filters being a part of the device are of course adapted to their purposes, so they could for example have surfaces acting as catalyzers in a reaction in which a toxic compound of the air is converted to a harmless compound.

[0024] The casing 1 could also be circular, so that the opening 3 will be circular, but all other shapes of the casing desired are of course possible.

Claims

1. A device in casings (1) for sucking air containing impurities away from a region, such as a working place, for example at a kitchen grate, under and near the casing, said device comprising a casing downwardly open, at least one suction opening (6) arranged inside the casing and connected to a suction member for generating an air flow from below, into the casing and out through the suction opening for conducting air away from the device, means (10-18, 28) for conducting a part of the air sucked from the interior of the casing back to the region of a lower edge of a side wall of the casing and members (23, 32', 34) for directing this air as a stream from said edge towards the interior of the casing, so that secondary air flows into the casing are induced at its edge region, characterized in that said means (10-18, 28) comprises at least a second suction opening (10) separately arranged with respect to the first suction opening (6) for sucking in the air for said stream, all air sucked through the first suction opening being conducted away from the device, that the second suction opening (10) is arranged closer to that side wall (4) of the casing which at the bottom is terminated by said edge than the first suction opening (6), and that the second suction opening is arranged at a substantial height inside the casing, at least in the upper half of the casing.

2. A device according to claim 1, characterized in that a second suction member (12) is connected to the second suction opening (10), and that the compression side of this suction member is connected to a member (13-15, 29) conducting the air to and emerging in the interior of the casing in the immediate vicinity of that side wall (4) of the casing, from the lower edge (22) of which said air stream emanates.

3. A device according to claim 1 or 2, characterized in that an element (2) extending substantially parallel to the longitudinal direction of the side wall (4) projects downwardly from the upper limitation of the casing at a distance from said side wall, that this element has a surface being inclined with respect to the vertical line and the middle normal of which is directed substantially towards the lower edge (22) of the side wall, and that the first suction opening (6) extends on said surface over substantially the whole length of the element.

4. A device according to claim 2 or claim 2 and 3, characterized in that a chamber (15, 29) extending along the long side of said side wall, i.e. in the horizontal direction, inside the casing between the second suction member (12) and the discharging of the conducting member is arranged to distribute the air from the suction member (12) substantially uniformly on one or several openings (17, 31) towards the interior of the casing extending together over substantially the whole extension of the chamber, and that said directing member comprises directing members (23, 32', 34) extending along said lower edge of the side wall, which are designed to direct the air arriving from the chamber inwardly-upwardly in the casing, preferably in the direction towards the first suction opening (6), so that an air stream is produced, which is substantially uniformly distributed along said side wall edge (22).

5. A device according to claim 4, characterized in that the chamber (15, 29) is located in the upper half of the casing, and that the openings (17, 31) are directed so as to produce an air stream, which is substantially continuous in the horizontal direction along the side wall (4), said air stream being directed from the upper portion of the wall and downwardly along the wall towards said lower edge (22).

6. A device according to claim 5, characterized in that the openings (17) are arranged at a distance from the side wall (4) and directed outwardly-downwardly towards the wall.

7. A device according to claim 6, characterized in that the second suction opening (10) is located at the upper limitation of the casing and directed substantially vertically downwardly in the casing.

8. A device according to claim 4, characterized in that the second suction opening (10) is directed substantially horizontally and substantially perpendicularly to the longitudinal direction of said side wall, that the chamber (29) in the vertical direction extends downwardly to the vicinity of the lower edge of the side wall, and that the openings (39) are located close to this lower edge and directed inwardly-upwardly towards the interior of the casing, preferably towards the first suction opening (6).

9. A device according to claim 4 and possibly any of the claims 5 to 8, characterized in that at least the second suction opening (10), the second suction member (12) and the distribution chamber are parts of an elongate insert (28), manufactured in advance, which may be inserted into the casing (1) and removed therefrom without moving the casing from said working place, and that the device has retaining means for retaining the insert along the upper limitation wall of the casing or alternatively the side wall thereof.

10. A device according to any of the preceding claims, characterized in that the casing (1) has two side walls (4), the longitudinal directions of which are substantially parallel to each other and both are located in a room over and in the proximity of a working place, that the device has a mirror image symmetry with a symmetry plane which is vertical and parallel to the longitudinal directions of the side walls, and that the symmetry plane traverses a room (2) located behind the two first suction openings (6), is common to these and connected to one single first suction member, while the other parts of the device occur in double sets.

Ansprüche

1. Vorrichtung innerhalb einer Absaughaube (1) zum Absaugen von Verunreinigungen enthaltende Luft unter der Absaughaube und in ihrer Nähe aus einem Bereich, beispielsweise einem Arbeitsplatz über zum Beispiel einem Küchenherd, wobei die genannte Vorrichtung ein nach unten hin offenes Gehäuse aufweist, zumindest eine innerhalb der Absaughaube angeordnete Ansaugöffnung (6) hat, welche mit einer Saugeinrichtung zum Erzeugen eines Luftstroms von unten in das Gehäuse und nach außerhalb durch die Ansaugöffnungen zum Wegleiten von Luft aus der Vorrichtung verbunden ist, Mittel (10 -18, 28) zum Leiten eines Teils der in das Innere des Gehäuses gesaugten Luft zurück in den Bereich der unteren Kante einer Seitenwand des Gehäuses hat und Mittel (23, 32', 34) zum Leiten dieser Luft als eine Strömung von der genannten Kante in das Innere des Gehäuses aufweist, so daß Sekundärluftströme in das Gehäuse in den Bereichen seiner Kanten hervorgerufen werden, dadurch gekennzeichnet, daß die genannten Mittel (10 - 18, 28) zumindest eine, getrennt von der ersten Ansaugöffnung (6) angeordnete zweite Ansaugöffnung (10) aufweist, um die Luft für die genannte Strömung anzusaugen, daß alle durch die erste Ansaugöffnung angesaugte Luft aus der Vorrichtung abgeführt wird, daß die zweite Ansaugöffnung (10) näher als die erste Ansaugöffnung (6) zur Seitenwand (4) des Gehäuses angeordnet ist, welches nach unten hin durch die genannten Kanten begrenzt wird, und daß die zweite Ansaugöffnung (10) innerhalb des Gehäuses in einer wesentlichen Höhe, zumindest innerhalb der oberen Hälfte des Gehäuses, angeordnet ist.

2. Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, daß eine zweite Saugeinrichtung (12) mit der zweiten Ansaugöffnung (10) verbunden ist und daß die Druckseite dieser Saugeinrichtung mit einer Einrichtung (13 - 15, 29) Verbindung hat, welche in das Gehäuse eintaucht und die Luft in unmittelbarer Nähe der genannten Seitenwand (4) des Gehäuses leitet, von dessen unteren Kante (22) aus die genannte Luftströmung abströmt.

3. Vorrichtung nach den Ansprüchen 1 oder 2, dadurch gekennzeichnet, daß ein Bauteil (2), welches sich im wesentlichen parallel zur Längsrichtung der Seitenwand (4) erstreckt, von der oberen Begrenzung des Gehäuses in einem Abstand von der genannten Seitenwand nach unten ragt, daß dieses Bauteil eine zur senkrechten Linie geneigte Fläche hat, deren Flächenmittennormale in etwa zur unteren Kante (22) der Seitenwand gerichtet ist, und daß die erste Ansaugöffnung (6) sich auf der genannten Fläche über im wesentlichen die gesamte Länge des Bauteils erstreckt.

4. Vorrichtung nach Anspruch 2 oder den Ansprüchen 2 und 3, dadurch gekennzeichnet, daß eine Kammer (15, 29) sich entlang der Längsseite der genannten Wand, also in horizontaler Richtung, innerhalb des Gehäuses zwischen der zweiten Saugeinrichtung (12) und dem Auslaß der Leiteinrichtung erstreckt, so daß die Luft von der Saugeinrichtung (12) im wesentlichen gleichförmig aus einer Öffnung (17, 31) oder mehreren in das Innere des Gehäuses verteilt wird, wobei die Öffnungen sich zusammen über die ganze Kammer erstrecken, und daß die genannte Leiteinrichtung Leiteinrichtungen (23, 32', 34) aufweist, welche sich entlang der genannten unteren Kante der Seitenwand erstrecken und so gestaltet sind, daß sie die von der Kammer kommende Luft schräg nach oben und innen in das Gehäuse leiten, vorzugsweise in Richtung der ersten Ansaugöffnung (6), so daß ein Luftstrom entsteht, der im wesentlichen entlang der genannten Kante (22) der Seitenwand gleichmäßig verteilt ist.

5. Vorrichtung nach Anspruch 4, dadurch gekennzeichnet, daß die Kammer (15, 29) in der oberen Hälfte des Gehäuses angeordnet ist und daß die Öffnungen (17, 31) so ausgerichtet sind, daß sie einen Luftstrom erzeugen, der im wesentlichen kontinuierlich in horizontaler Richtung entlang der Seitenwand (4) verläuft, wobei der genannte Luftstrom vom oberen Bereich der Wand nach unten entlang der Wand zur genannten unteren Kante (22) geleitet wird.

6. Vorrichtung nach Anspruch 5, dadurch gekennzeichnet, daß die Öffnungen (17) mit Abstand von der Seitenwand (4) angeordnet sind und nach unten und abwärts zur Wand hin gerichtet sind.

7. Vorrichtung nach Anspruch 6, dadurch gekennzeichnet, daß die zweite Ansaugöffnung (10) an der oberen Begrenzung des Gehäuses angeordnet und im wesentlichen vertikal abwärts im Gehäuse ausgerichtet ist.

8. Vorrichtung nach Anspruch 4, dadurch gekennzeichnet, daß die zweite Ansaugöffnung (10) im wesentlichen horizontal und im wesentlichen rechtwinklig zur Längsrichtung der genannten Seitenwand ausgerichtet ist, daß die Kammer (29) sich in vertikaler Richtung abwärts bis in die Nähe der unteren Kante der Seitenwand erstreckt und daß die Öffnungen (39) nahe der unteren Kante angeordnet und nach innen und oben in das Innere des Gehäuses hinein, vorzugsweise zur ersten Ansaugöffnung hin, ausgerichtet sind.

9. Vorrichtung nach Anspruch 4 und gegebenenfalls einem der Ansprüche 5 bis 8, dadurch gekennzeichnet, daß zumindest die zweite Ansaugöffnung (10), die zweite Saugeinrichtung (12) und die Verteilungskammer Teile eines länglichen, vorgefertigten Einsatzes (28) sind, welcher in das Gehäuse (1) eingefügt und aus ihm ausgebaut werden kann, ohne daß das Gehäuse von dem genannten Arbeitsplatz entfernt werden muß, und daß die Vorrichtung eine Halterung zum Halten des Einsatzes an der oberen Begrenzungswand des Gehäuses oder alternativ seiner Seitenwand aufweist.

10. Vorrichtung nach einem der vorangehenden Ansprüche, dadurch gekennzeichnet, daß das Gehäuse (1) zwei Seitenwände (4) hat, deren Längsrichtungen im wesentlichen parallel zueinander verlaufen und die beide in einem Raum oberhalb und in der Nähe eines Arbeitsplatzes angeordnet sind, daß die Vorrichtung eine Spiegelsymmetrie aufweist, wobei die Symmetrieebene vertikal und parallel zu den Längsrichtungen der Seitenwände verläuft, und daß die Symmetrieebene einen hinter den beiden ersten Ansaugöffnungen vorgesehenen, den Ansaugöffnungen gemeinsamen Raum (2) kreuzt, der mit einer einzigen ersten Saugeinrichtung verbunden ist, während die anderen Teile der Vorrichtung doppelt vorgesehen sind.

Revendications

1. Dispositif placé dans un logement (1) pour éloigner, par aspiration, de l'air contenant des impuretés d'une région, telle qu'un poste de travail, par exemple à l'endroit d'une grille de cuisine située sous le logement et à proximité de celui-ci, ledit dispositif comprenant un logement ouvert vers le bas, au moins une ouverture d'aspiration (6) prévue à l'intérieur du logement et reliée à un élément d'aspiration en vue d'engendrer un flux d'air depuis le bas qui entre dans le logement et sort par l'ouverture d'aspiration pour éloigner de l'air du dispositif, des moyens (10-18, 28) pour ramener une partie de l'air aspiré de l'intérieur du logement vers la région d'un bord inférieur d'une paroi latérale du logement et des éléments (23, 32', 34) pour diriger cet air sous la forme d'un flux dudit bord vers l'intérieur du logement étant prévus, de manière à ce que des flux d'air secondaires vers le logement soient amorcés dans dans le logement dans la région du bord de celui-ci,
caractérisé en ce que lesdits moyens (10-18, 28) comprennent au moins une deuxième ouverture d'aspiration (10), séparée de la première ouverture d'aspiration (6), afin d'aspirer l'air dudit flux, tout l'air aspiré à travers la première ouverture d'aspiration étant éloigné du dispositif,
en ce que la deuxième ouverture d'aspiration (10) est placée plus près de la paroi latérale (4) du logement qui se termine au fond par ledit bord, que la première ouverture d'aspîration (6),
et en ce que la deuxième ouverture d'aspiration est placée à une hauteur substantielle à l'intérieur du logement, au moins dans la moitié supérieure de celui-ci.

2. Dispositif selon la revendication 1,
caractérisé en ce qu'un deuxième élément d'aspiration (12) est relié à la deuxième ouverture d'aspiration (10), et en ce que le côté compression de cet élément d'aspiration est relié à un élément (13-15, 29) qui amène l'air vers le logement et qui débouche à l'intérieur de celui-ci, au voisinage immédiat de la paroi latérale (4) de celui-ci , du bord inférieur (22) de laquelle émane ledit flux d'air.

3. Dispositif selon la revendication 1 ou 2,
caractérisé en ce qu'un élément (2) qui s'étend sensiblement parallèlement à la direction longitudinale de la paroi latérale (4) fait saillie vers le bas depuis la limite supérieure du logement et à une certaine distance de la paroi latérale,
en ce que cet élément présente une surface inclinée par rapport à la ligne verticale, dont la normale centrale est sensiblement orientée vers le bord inférieur (22) de la paroi latérale,
et en ce que la première ouverture d'aspiration (6) s'étend sur ladite surface sur sensiblement toute la longueur de l'élément.

4. Dispositif selon la revendication 2 ou selon les revendications 2 et 3,
caractérisé en ce qu'une chambre (15, 29) qui s'étend le long du côté longitudinal de ladite paroi latérale, à savoir dans la direction horizontale, à l'intérieur du logement, entre le deuxième élément d'aspiration (12) et la sortie de l'élément conducteur, est agencée pour répartir l'air venant de l'élément d'aspiration (12) de manière sensiblement uniforme à travers une ou plusieurs ouvertures (17, 31) vers l'intérieur du logement, ces ouvertures s'étendant dans l'ensemble sur toute l'extension de la chambre,
et en ce que ledit élément répartiteur comprend des moyens répartiteurs (23, 32', 34) qui s'étendent le long du bord inférieur de la paroi latérale et sont destinés à orienter l'air qui arrive de la chambre vers l'intérieur du logement et en particulier vers le haut de celui-ci, de préférence vers la première ouverture d'aspiration (6), de manière à engendrer un flux d'air uniformément réparti le long du bord (22) de la paroi latérale.

5. Dispositif selon la revendication 4,
caractérisé en ce que la chambre (15, 29) est située dans la moitié supérieure du logement et que les ouvertures (17, 31) sont orientées de manière à engendrer un flux d'air vers le bas sensiblement continu dans la direction horizontale le long de la paroi latérale (4), ledit flux d'air étant dirigé de la partie supérieure de la paroi, le long de ladite paroi, en direction dudit bord inférieur (22).

6. Dispositif selon la revendication 5,
caractérisé en ce que les ouvertures (17) sont disposées à une certaine distance de la paroi latérale (4) et orientées vers l'extérieur et le bas, en direction de la paroi.

7. Dispositif selon la revendication 6,
caractérisé en ce que la deuxième ouverture d'aspiration (10) est située dans la limite supérieure du logement et orientée sensiblement verticalement vers le bas du logement.

8. Dispositif selon la revendication 4,
caractérisé en ce que la deuxième ouverture d'aspiration (10) est orientée sensiblement horizontalement et sensiblement perpendiculairement à la direction longitudinale de la paroi latérale,
en ce que la chambre (29) s'étend dans la direction verticale vers le bas, en direction du voisinage du bord inférieur de la paroi latérale,
et en ce que les ouvertures (39) sont situées près de ce bord inférieur et orientées vers l'intérieur et le haut du logement, de préférence vers la première ouverture d'aspiration (6).

9. Dispositif selon la revendication 4 et éventuellement l'une des revendications 5 à 8,
caractérisé en ce qu'au moins la deuxième ouverture d'aspiration (10), le deuxième élément d'aspiration (12) et la chambre de répartition font partie d'un dispositif allongé à insérer (28), réalisé à l'avance, qui peut être inséré dans le logement (1) et en être extrait sans qu'il soit nécessaire de déplacer ledit logement du poste de travail,
et en ce que le dispositif présente des moyens de retenue pour retenir le dispositif inséré le long de la paroi supérieure du logement ou de la paroi latérale de celui-ci.

10. Dispositif selon, l'une des revendications précédentes,
caractérisé en ce que le logement (1) comporte deux parois latérales (4) dont les directions longitudinales sont sensiblement parallèles entre elles et qui sont toutes les deux disposées dans un espace au-dessus et à proximité d'un poste de travail,
en ce que le dispositif est inversément symétrique à un plan de symétrie qui est vertical et parallèle aux directions longitudinales des parois latérales,
et en ce que le plan de symétrie traverse un espace (2) situé derrière les deux premières ouvertures d'aspiration (6), est commun à celles-ci et relié à un seul premier élément d'aspiration, tandis que les autres parties du dispositif sont toujours prévues par paires.

Drawing