WO2001071261A1

WO2001071261A1 - Airflow controlling valve device

Info

Publication number: WO2001071261A1
Application number: PCT/SE2001/000534
Authority: WO
Inventors: Evert Krantz
Original assignee: Freshman Flimmer Ab
Priority date: 2000-03-21
Filing date: 2001-03-15
Publication date: 2001-09-27
Also published as: SE516042C2; SE0000970L; SE0000970D0; AU2001239640A1

Abstract

The invention relates to an airflow controlling valve device of the disc-type that may be used either as a supply air device or as an exhaust air device. Backwards from a disc (9), a sleeve (10) extends, which is insertable with an air-tightening fit in an air-carrying duct (5), a filter (2) including a covering (26) with same cross-section shape as the sleeve being detachably mounted inside the sleeve, the covering being inserted with an air-tightening fit in the sleeve. Furthermore, the disc (9) has a lower flange (16) which extends backwards from a lower edge portion and is arranged to co-operate with a lower flange (22) of a fastening plate (3), said flanges overlapping each other in order to make airflow in the direction downwards from the disc impossible, irrespective of the axial setting of the disc.

Description

AIRFLOW CONTROLLING VALVE DEVICE

Technical Field of the Invention

This invention relates to an airflow controlling valve device of the type that comprises a disc, which is mount- able in connection with an air-carrying duct mouthing in a wall, and is axially movable in relation thereto in order to vary the air throughput area between the disc and the wall.

Prior Art

Airflow controlling valve devices of the disc-type can be used not only as supply air devices but also as exhaust air devices. Irrespective of the field of use, previously known, conventional disc valve devices are distinguished by an unbroken, circu fering air gap being formed between the peri- metric edge portion of the disc and the wall behind. When the valve device is used as a supply air device, this means that air is fed out in the room in all directions from the disc, more precisely also downwards, what in turn implies that the usually relatively cold supply air falls down along the wall and gives rise to draught in the room. Another nuisance of conventional disc valve devices is that they lack an air-cleaning ability. For instance, in the usual case when the valve device is mounted in a duct in an external wall of a building and serves as a supply air device, consequently more or less par^¬ ticle-mixed exterior air will be taken in directly into the building without being cleaned.

Objects and Features of the Invention The present invention aims at obviating the above- mentioned shortcomings of previously known valve devices of the disc-type and at providing an improved valve device. Therefore, a primary object of the invention is to provide a valve device with an effective air-cleaning ability which with a retained air-cleaning ability may be used as a supply air device or, alternatively, as an exhaust air device, the device in the first-mentioned case of application being capable of giving a good, draught-free air comfort upon the entrance of the air in the room. An additional object is to provide a valve device that is structurally simple and that may be readjusted between different settings in a fast and smooth way.

According to the invention, at least the primary object is attained by the features defined in the characteriz- ing clause of claim 1. Preferred embodiments of the invention are furthermore defined in the dependent claims.

Brief Description of the Appended Drawings In the drawings: Fig 1 is a perspective exploded view showing a first embodiment of a valve device according to the invention,

Fig 2 is an analogous exploded view showing an alternative embodiment of the valve device,

Fig 3 is a longitudinal section through the valve device according to fig 1 shown in a closing position,

Fig 4 is a corresponding longitudinal section showing the same valve device in an open position, the device serving as a supply air device,

Fig 5 is an additional longitudinal section showing the valve device serving as an exhaust air device, and

Fig 6 is a front view of the valve device shown in figs 1, 3 and 4.

Detailed Description of Preferred Embodiments of the Invention In fig 1, a valve device according to the invention serving as a supply air device is visualised. This device includes a disc unit 1, a filter 2 and a fastening plate 3. In this case, the valve device is shown in connection with an external wall 4 of a building, in which wall there is an air- carrying duct 5 that is delimited by a cylindrical pipe 6, which is accommodated in a hole 7 in the wall. At the outer end thereof, the pipe 6 is connected to a conventional air inlet device 8.

Characteristic of the invention is that the disc 9 of the unit 1 is connected to a sleeve 10 extending backwards from the disc, the sleeve being insertable with an air-tightening fit in the pipe 6. In practice, the sleeve may have a slightly smaller outer diameter than the inner diameter of the pipe 6 in order to provide a fine fit. It is also possible to dispose one or more elastic sealing rings in the interface between the pipes. At the end thereof connected to the disc 9, the sleeve 10 has slits 11 through which air may pass. In the example shown in fig 1, the disc 9 includes a rectangular plate 12 (see also figs 3 and 4) with which a circumfering border is connected comprising four flanges, viz . an upper flange 13, two side flanges 14, 15, as well as a lower flange 16. Said lower flange 16 is wider than the other flanges and will, therefore, protrude a distance backwards from the side flanges. In the trough-shaped space that is delimited by the flanges, a sheet 17 of sound-absorbing material, e.g. a fibre mat is arranged.

The fastening plate 3, which like the disc 9 has a rectangular basic shape, co-operates with the disc unit 1. Said plate may be fastened against the inside of the wall 4 by means of screws 19. In the plate, there is a central hole 20, the diameter of which is slightly larger than the outer diameter of the duct-confining pipe 6, which projects somewhat (approx. 5- 10 mm) from the inside of the wall 4. Also the fastening plate 3 has a circumfering border composed of four flanges, of which the upper and lower flanges 21, 22 are somewhat wider than the two opposite side flanges 23.

The filter 2 is advantageously of the type that includes a set of fine threads 24 of an electrostatically chargeable material. Particle-separating filters of this type are previously known by, for instance, WO 95/00248, WO 95/33567 and WO 95/33569. The threads 24 may be carried by a body 25 having a plurality of diminutive, transmitting ducts that are delimited by a lattice of thin walls. The body is substantially flat and extends transverse to an external (in this case cylin- drical) covering 26, which is insertable in the sleeve 10, more precisely with an air-tightening fit (either by the fact that the diameter difference is minimal or by the fact that particu^¬ lar sealing rings have been arranged in the interface between the covering and the sleeve) . At the opposite ends thereof, the filter covering 26 has grips 27, which in this case are in the form of folded-in portions of the wall of the covering. In practice, the filter covering may consist of plastic or stiff cardboard. It should be observed that the body 25 is located approximately in the centre of the covering, the electrostatically chargeable threads 24 extending from the carrier approximately up to one of the mouths of the covering.

Reference is now made to figs 3,4 and 6, which illus- trate the valve device in a mounted state. In fig 3, the valve device is shown in a closing position in which the airflow is either completely interrupted or alternatively reduced to a minimum level. In fig 4, the valve device is shown in an opening position in which a considerable flow of supply air may be taken into the room inside the wall 4. In this case, the disc 9 has been drawn out a distance from the inner end position according to fig 3. Between the upper and side flanges 13, 14, 15 of the plate and the corresponding flanges of the fastening plate 3 a substantially U-shaped air gap therefore being formed through which air may pass. However, the wide, lower flange 16 of the plate still overlaps the corresponding flange 22 of the fastening plate 3. This means that the incoming air is distributed upwards and sidewards, but not downwards in the room, as is illustrated by the arrows in fig 6. .In other words, no down- draught is obtained because the fresh air taken in is mixed with the warm air in the upper part of the room.

When the air is taken in, the same will pass the filter 2 and be freed from the accompanying particles by means of the electrostatical effect of the threads 24, which entails that the particles get stuck on the threads.

For altering the size of the airflow, if required, the disc unit 1 may be displaced axially in relation to the fixed pipe 6, the width of the above-mentioned air gap being altered. Displacement of the disc unit between different set- tings may be carried out by means of a grip 28 on the bottom side of the disc. By means of a cord 29 shown in fig 1 is out^¬ lined how the device may include means for blocking the disc in the outer end position in which the airflow is maximal. After mounting the fastening plate and insertion of the sleeve 10 in the pipe 6, the cord 29 may be hooked on a projection 30 on the fastening plate. Of course, the device may also be formed with other means for blocking the disc in the outer end position. In practice, the distance between the inner and outer end position of the disc may be within the range of 10-20 mm, the width of the air-transmitting gap being varied in parity thereto.

In fig 2, an alternative embodiment is shown in which the disc 9 has a circular basic shape, the circumfering border being cylindrical instead of rectangular as in the example according to fig 1. In this case, the disc unit co-operates with a fastening plate 3 having a circular basic shape. In other words, the plate is ring-shaped. At the lower edge thereof, said plate has a curved or partly cylindrical lower flange 22 having the same function as the flange 22 according to fig 1, i.e. to inhibit entrance of air in the room in the direction downwards from the valve device.

A particular advantage of the valve device according to the invention is that the same with a retained filter effect in a fast and simple way may be modified to either serve as a supply air device or as an exhaust air device. Thus, if the device should be used as exhaust air device, the filter 2 is mounted in the way that is shown in fig 5. In this case, the filter is mounted so that the electrostatically chargeable threads 24 extend backwards from the appurtenant carrier 25 instead of forwards, towards the disc as has been shown in other embodiments. By the fact that the filter covering 26 is formed with manually grippable grips 27 at the opposite ends thereof, the filter may in a simple way be drawn out of the sleeve 10 to enable necessary filter exchanges irrespective of the device serving as a supply air device or as an exhaust air device .

Feasible Modifications of the Invention The invention is not solely restricted to the embodi^¬ ments described and shown in the drawings. Thus, it is for instance feasible to form the sleeve and the covering, respec^¬ tively, with a quadrangular or another polygonal cross-section shape corresponding to the cross-section shape of the air duct (instead of a cylindrical sleeve and a cylindrical filter cov^¬ ering, respectively) . Furthermore, the air-transmitting effect of the sleeve may be provided in another way than by means of two opposite air gaps 11 of the type that has been exemplified in the drawings. It is also feasible to modify the shape of the circumfering border of the disc. Thus, the essential thing is that the disc has a lower flange that co-operates with an analogous lower flange of the fastening plate with the purpose of counteracting downdraught upon entrance of the air in the room. Furthermore, it is also feasible to use other filters than electrostatic filters of the self-acting type, although such filters, however, are preferred in practice. The valve device may, of course, be used also in larger, central ventilating systems and not only in external walls.

Claims

1. Airflow controlling valve device, including a disc (9), which is mountable in connection to an air-carrying duct (5) mouthing in a wall (4), and is axially movable in relation thereto in order to vary the air throughput area between the disc and the wall, c h a r a c t e r i z e d in that a sleeve (10) extends backwards from the disc (9), which sleeve is insertable in the duct (5) with an air-tightening fit, that a filter (2) including a covering (26) is detachably mounted inside the sleeve, which filter has the same cross-section shape as the sleeve and is inserted with an air-tightening fit therein, and that the disc (9) has a lower flange (16) extending backwards from a lower edge portion and is arranged to co- operate with a fastening plate (3) having a second lower flange (22), which overlaps the lower flange (16) of the disc (9) for making airflow in the downward direction from the disc impossible, irrespective of the axial setting of the disc.

2. Valve device according to claim 1, c h a r a c t e r i z e d in that said filter (2) comprises a set of fine threads (24) of an electrostatically chargeable material.

3. Valve device according to claim 2, c h a r a c t e r i z e d in that the electrostatically chargeable threads (24) are carried by a body (25) in the form of a lattice extending transverse to the covering (26) .

4. Valve device according to claim 3, c h a r a c t e r i z e d in that the filter covering (26) has grips (27) at opposite ends in order to enable withdrawal of the same, irrespective of the covering being mounted with the filter threads (24) turned forwards or backwards from said body (25) .