WO1995028233A1

WO1995028233A1 - Ventilating device and air supply means for use therein

Info

Publication number: WO1995028233A1
Application number: PCT/SE1995/000384
Authority: WO
Inventors: Kenneth Neikter; Jan-Mats Eneroth
Original assignee: ABB Flaekt AB; Flaekt AB
Current assignee: ABB Technology FLB AB
Priority date: 1994-04-14
Filing date: 1995-04-11
Publication date: 1995-10-26
Anticipated expiration: 1996-10-14
Also published as: SE9401261D0; AU2377495A; SE9401261L; SE502699C2

Abstract

A device for ventilating a compartment, in which pollutants are spread and which is delimited by walls (3), a ceiling (4) and a floor (5), comprises at least one air supply means (7), which is arranged by the ceiling to blow air into the compartment, and at least one air exhaust means (9), which is arranged by the floor to draw contaminated air out of the compartment. The air supply means (7) is in the form of an elongate channel, which has a cross-sectionally arcuate channel wall (12) formed with a plurality of air outlet holes resulting in air flows perpendicular to the channel wall, and which extends along the connecting line (L) between the ceiling (4) and one of the compartment walls (3), the convex side of the channel wall (12) facing outwards, and its longitudinal edges being applied against the ceiling (4) and the wall (3) along respectively a first and a second line (respectively L1 and L2). The cross-sectionally arcuate channel wall (12) of the air supply means is so designed that the angle between that part of respectively the ceiling (4) and/or the wall (3) which is located respectively between the first line (L1) and the connecting line (L) and between the second line (L2) and the connecting line (L) and that part of the channel-wall tangent plane along respectively the first and the second line (respectively L1 and L2) which extends into the compartment, is 95-120°.

Description

VENTILATING DEVICE AND AIR SUPPLY MEANS FOR USE THEREIN

This invention concerns a ventilating device for ventilating a compartment, such as a spray booth, in which solid, liquid or gaseous pollutants are spread and which is delimited by walls, a ceiling and a floor, said ventilating device comprising at least one air supply means, which is arranged in the vicinity of the ceiling of the compartment to blow air into the compartment, and at least one air exhaust means, which is arranged in the vicinity of the floor of the compartment to draw con- taminated air out of the compartment, the air supply means being in the form of an elongate channel, which has a cross-sectionally arcuate channel wall formed with a plurality of air outlet holes adapted to result in air flows that are essentially perpendicular to the channel wall, and which extends along the connecting line between the ceiling and one of the compartment walls with the convex side of the cross-sectionally arcuate channel wall facing outwards and with the one longitudinal edge of the channel wall being applied against the ceiling along a first line and the other longitudinal edge of the channel wall being applied against the wall along a second line.

The invention further relates to an air supply means especially intended for use in such a ventilating device, said air supply means being in the form of an elongate channel, which has a cross-sectionally arcuate channel wall formed with a plurality of air outlet holes adapted to result in air flows that are essentially perpendicular to the channel wall, and which is adapted to be disposed along the connecting line between two flat surfaces, such as a ceiling surface and a wall surface, which intersect to form between them a compartment, with the convex side of the cross-sectionally arcuate channel wall facing out¬ wards and with the one longitudinal edge of the channel wall being applied against the one flat surface along a first line and the other longitudinal edge of the channel wall being applied against the other flat surface along a second line.

In a common prior-art device for ventilating a spray booth where vehicle bodies are painted, the air supply means consists of a grating provided in the spray-booth ceiling, as well as a filter mat supported thereby. The grating and the filter mat cover the entire ceiling sur¬ face and produce an air flow that is evenly distributed over the spray booth. Air contaminated by paint and sol¬ vents, if any, is drawn out through a grating forming the spray-booth floor. However, considerable air flows are required if this known device is to work. Another draw¬ back is that the device is unable, at least in certain applications, to keep the spray-booth walls free from paint in a satisfactory fashion, which is necessary if high-quality painting is to be obtained and if the in¬ spection windows usually provided in the spray booth are to remain transparent. Japanese Patent Application 86JP-141,506 discloses a device for circulating the air in a room. This device comprises an air supply means, which is in the form of an elongate channel having a cross-sectionally arcuate chan¬ nel wall. The channel extends along the connecting line between the ceiling of the room and one of the walls, with the convex side of the cross-sectionally arcuate channel wall facing outwards and with the one longitudi¬ nal edge of the channel wall being applied against the ceiling and the other longitudinal edge of the channel wall being applied against the wall. An air exhaust means is provided along the connecting line between the floor and a wall opposite to the first-mentioned wall of the room.

A first object of this invention is to provide, on the basis of the knowledge found in the Japanese patent application mentioned above, a ventilating device which is especially intended for spray booths and which obvi- ates the drawbacks from which suffers the common prior- art ventilating device described above.

According to the invention, this object is achieved by a ventilating device which is of the type stated by way of introduction and which is characterised in that the cross-sectionally arcuate channel wall of the air supply means is so designed that the angle between that part of respectively the ceiling and/or the wall which is located respectively between said first line and the con- necting line and between said second line and the con¬ necting line and that part of the channel-wall tangent plane along respectively said first and said second line which extends into the compartment, is 95-120°, prefer¬ ably 105°. In a preferred embodiment, the channel wall has, in cross-section, the shape of a circular arc, whose central angle is 95-120°, and the air supply means is so posi¬ tioned that the centre of the circular arc is located in the plane of the wall or the ceiling. A second object of this invention is to provide an air supply means which is especially intended for use in a ventilating device according to the invention and which enables the first object to be attained.

According to the invention, the second object is achieved by an air supply means which is of the type stated by way of introduction and which is characterised in that the cross-sectionally arcuate channel wall is so designed that, when it is placed along the connecting line as indicated above, the angle between that part of respectively said one flat surface and/or said other flat surface which is located respectively between said first line and the connecting line and between said second line and the connecting line and that part of the channel-wall tangent plane along respectively said first and said second line which extends into the compartment, is 95- 120°, preferably 105°. In a preferred embodiment, the channel wail has, in cross-section, the shape of a circular arc.

In a first variant of this embodiment intended to be used when the two flat surfaces intersect at a right angle, the central angle of the circular arc is 100-150°, the channel wall being adapted to be so placed along the connecting line that the bisector of the central angle of the circular arc cuts the connecting line.

In a second variant, which also is intended to be used when the two flat surfaces intersect at a right angle, the central angle of the circular arc is 95-120°, the channel wall being adapted to be so placed along the connecting line that the centre of the circular arc is located within one of the two flat surfaces. The invention will now be described in more detail with reference to the accompanying drawings, in which

Fig. 1 is a schematic view of a spray booth equipped with a ventilating device according to the invention;

Fig. 2 is an enlarged cross-section showing an air supply means forming part of the ventilating device shown in Fig. 1;

Fig. 3 illustrates the geometrical relationships for the air supply means shown in Fig. 2;

Fig. 4 is similar to Fig. 3, but shows the geometri- cal relationships when the air supply means of Fig. 2 oc¬ cupies an alternative position; and

Fig. 5 is similar to Figs 3 and 4, but shows the geometrical relationships for an alternative embodiment of the air supply means. Fig. 1 shows a spray booth 1 for painting vehicle bodies 2. The spray booth 1 is delimited by two side walls 3, a ceiling 4, a floor 5 and openable end walls (not shown) . The floor 5 consists of a grating. Transpar¬ ent inspection windows 6 are provided in the walls 3. An air supply means 7 is arranged along the con¬ necting line L between the ceiling 4 and the one side wall 3, as well as along the connecting line L between the ceiling 4 and the other side wall 3. Each air supply means 7 is, via one or more ducts 8, connected to a sys¬ tem (not shown) for supplying air to the spray booth 1. Two juxtaposed air exhaust means 9 are arranged be- neath the floor 5 of the spray booth 1 to draw contami¬ nated air out of the spray booth 1.

Each air supply means 7 is in the form of an elon¬ gate channel extending over the entire length of the spray booth 1. The channel has a flat, first channel wall 10 (Fig. 2) , a flat, second channel wall 11, and an arcu¬ ate, third channel wall 12. The two flat channel walls 10 and 11, which are made of sheet metal, are interconnected at a right angle along one of their longitudinal edges. The arcuate, third channel wall 12 extends, in its trans- verse direction, between the free longitudinal edges of the two flat channel walls 10 and 11, its convex side facing outwards. The arcuate channel wall 12 consists of a metal sheet 12a, which is perforated over its entire surface, as well as a filter mat 12b, which is supported by the metal sheet 12a and is applied against the inside thereof. At its longitudinal edges, the metal sheet 12a is, for instance by means of screws 13, fixed to the two flat channel walls 10 and 11. Each air supply means 7 is so attached to the spray booth 1, for instance by means of screws (not shown) , that its flat channel wall 10 is applied against the wall 3 of the spray booth 1 and its flat channel wall 11 is applied against the ceiling 4 of the spray booth 1.

The arcuate channel wall 12 of the air supply means 7 shown in Figs 1-4 has, in cross-section, the shape of a circular arc B, whose central angle α is 95-120°, pref¬ erably 105°.

In Figs 1-3, the air supply means 7 is so positioned that the centre C of the circular arc B is located in the plane of the roof, which means that the channel-wall tan¬ gent plane Tl along the line LI, along which the channel wall 12 is applied against the ceiling 4 with one longi- tudinal edge, forms a right angle with the plane of the ceiling, and that the channel-wall tangent plane T2 along the line L2, along which the channel wall 12 is applied against the wall 3 with its other longitudinal edge, forms an angle β with the plane of the wall. The angle β is, as appears from Fig. 3, the angle between that part of the wall 3 which extends between the connecting line L and the line L2 and that part of the tangent plane T2 which extends into the spray booth 1. Thus, the angle β is identical with the angle α, i.e. is 95-120°, prefer¬ ably 105°.

In Fig. 4, the air supply means 7 is so positioned that the centre C of the circular arc B is located in the plane of the wall instead of that of the ceiling. This means that the channel-wall tangent plane T2 along the line L2 forms a right angle with the plane of the wall, and that the channel-wall tangent plane Tl along the line LI forms an angle γ with the plane of the ceiling. The angle γ is, as appears from Fig. 4, the angle between that part of the ceiling 4 which extends between the con¬ necting line L and the line LI and that part of the tan¬ gent plane Tl which extends into the spray booth 1. Thus, the angle γ is identical with the angle α, i.e. is 95- 120°, preferably 105°. The air fed to the air supply means 7 via the duct or ducts 8 is distributed in the spray booth 1 by the air supply means 7. The perforated metal sheet 12a and the filter mat 12b supported thereby produce air flows which are perpendicular to the channel wall 12 and which, in Fig. 2, are indicated by a number of arrows which thus, if extended rearwards, all cut the centre C of the circu¬ lar arc B.

When the air supply means 7 occupies the position shown in Figs 1-3, there is thus obtained, in the vicin- ity of the ceiling 4, an air flow essentially parallel to the ceiling, whereas the air flow in the vicinity of the wall 3 is directed obliquely towards the wall, creating an increased air flow along the wall 3, which thus is kept free from paint.

When the air supply means 7 occupies the position shown in Fig. 4, there is likewise obtained, in the vi- cinity of the wall 3, an air flow essentially parallel to the wall, whereas the air flow in the vicinity of the ceiling 4 is directed obliquely towards the latter, ena¬ bling the ceiling to be kept clean, should this be desir¬ able in some particular application. In the spray-booth application, the position of the air supply means shown in Figs 1-3 is, of course, the most convenient one.

In the embodiment illustrated in Fig. 5, the arcuate channel wall 12 of the air supply means 7 has, in cross- section, the shape of a circular arc B. However, the cen¬ tral angle α of the circular arc B is here 100-150°, preferably 120°. In Fig. 5, the air supply means 7 is so positioned that the bisector A of the central angle α of the circular arc B cuts the connecting line L. As a re- suit, the tangent plane Tl along the line LI forms an angle γ with the plane of the ceiling, and the tangent plane T2 along the line L2 forms an angle β with the plane of the wall, the angles β and γ being defined in the manner indicated above. Owing to the symmetrical po- sition of the air supply means 7, the angles β and γ are here identical, namely 45° + α/2, i.e. 95-120°, prefer¬ ably 105°.

Thus, the symmetrical position of the air supply means 7 shown in Fig. 5 results, in the vicinity of the ceiling 4, in an air flow that is directed obliquely to¬ wards the ceiling and, in the vicinity of the wall 3, in an air flow that is directed obliquely towards the wall.

Claims

1. A ventilating device for ventilating a compart¬ ment, such as a spray booth (1), in which solid, liquid or gaseous pollutants are spread and which is delimited by walls (3), a ceiling (4) and a floor (5), said venti¬ lating device comprising at least one air supply means (7), which is arranged in the vicinity of the ceiling of the compartment to blow air into the compartment, and at least one air exhaust means (9), which is arranged in the vicinity of the floor of the compartment to draw con¬ taminated air out of the compartment, the air supply means (7) being in the form of an elongate channel, which has a cross-sectionally arcuate channel wall (12) formed with a plurality of air outlet holes adapted to result in air flows that are essentially perpendicular to the chan¬ nel wall, and which extends along the connecting line (L) between the ceiling (4) and one of the compartment walls (3) with the convex side of the cross-sectionally arcuate channel wall (12) facing outwards and with the one longi- tudinal edge of the channel wall being applied against the ceiling (4) along a first line (LI) and the other longitudinal edge of the channel wall being applied against the wall (3) along a second line (L2), c h a r ¬ a c t e r i s e d in that the cross-sectionally arcuate channel wall (12) of the air supply means (7) is so de¬ signed that the angle (respectively γ and β) between that part of respectively the ceiling (4) and/or the wall (3) which is located respectively between said first line (LI) and the connecting line (L) and between said second line (L2) and the connecting line (L) and that part of the channel-wall tangent plane (respectively Tl and T2) along respectively said first and said second line (respectively LI and L2) which extends into the compart¬ ment, is 95-120°.

2. A ventilating device as set forth in claim 1, c h a r a c t e r i s e d in that said angle (γ, β) is 105°.

3. A ventilating device as set forth in claim 1 or 2, c h a r a c t e r i s e d in that the channel wall (12) has, in cross-section, the shape of a circular arc (B) , whose central angle (α) is 95-120°, and that the air supply means (7) is so positioned that the centre (C) of the circular arc (B) is located in the plane of the wall or the ceiling.

4. An air supply means, especially intended for use in a ventilating device as set forth in claim 1, said air supply means (7) being in the form of an elongate chan¬ nel, which has a cross-sectionally arcuate channel wall (12) formed with a plurality of air outlet holes adapted to result in air flows that are essentially perpendicular to the channel wall, and which is adapted to be disposed along the connecting line (L) between two flat surfaces (3, 4), such as a ceiling surface (4) and a wall surface (3) , which intersect to form between them a compartment, with the convex side of the cross-sectionally arcuate channel wall (12) facing outwards and with the one longi¬ tudinal edge of the channel wall being applied against the one flat surface (4) along a first line (LI) and the other longitudinal edge of the channel wall being applied against the other flat surface (3) along a second line (L2) , c h a r a c t e r i s e d in that the cross-sec¬ tionally arcuate channel wall (12) is so designed that, when it is placed along the connecting line (L) as indi- cated above, the angle (γ, β) between that part of re¬ spectively said one flat surface (4) and/or said other flat surface (3) which is located respectively between said first line (LI) and the connecting line (L) and between said second line (L2) and the connecting line (L) and that part of the channel-wall tangent plane (respec¬ tively Tl and T2) along respectively said first and said second line (respectively LI and L2) which extends into the compartment, is 95-120°.

5. An air supply means as set forth in claim 4, c h a r a c t e r i s e d in that said angle (γ, β) is 105°.

6. An air supply means as set forth in claim 4, c h a r a c t e r i s e d in that the channel wall (12) has, in cross-section, the shape of a circular arc (B) .

7. An air supply means as set forth in claim 6, which is intended to be used where the two flat surfaces (3, 4) intersect at a right angle, c h a r a c t e r ¬ i s e d in that the central angle (α) of the circular arc (B) is 100-150°, the channel wall (12) being adapted to be so placed along the connecting line (L) that the bisector (A) of the central angle (α) of the circular arc (B) cuts the connecting line (L) .

8. An air supply means as set forth in claim 6, which is intended to be used where the two flat surfaces (3, 4) intersect at a right angle, c h a r a c t e r - i s e d in that the central angle (α) of the circular arc (B) is 95-120°, the channel wall (12) being adapted to be so placed along the connecting line (L) that the centre (C) of the circular arc (B) is located within one of the two flat surfaces (3, 4) .