Supply air valve

Abstract

 The present invention relates to a supply air valve (1) with an inlet (2) for guiding replacement air into a flow channel (4) of the supply air valve. The supply air valve (1) also comprises an air flow directing element (5) for directing air guided into the flow channel (4) of the supply air valve into a room (20). The supply air valve (1) further comprises a damping member (9), whose at least one wall is oblique to the direction of flow of supply air flowing via the inlet (2), and a control member (10), by means of which the flow area between the damping member (9) and the control member (10) is arranged to be adjusted.

Description

Field of the invention

[0001] The present invention relates to a supply air valve with an inlet for introducing replacement air into the supply air valve, and an air flow directing element for directing the air introduced into the supply air valve into a room.

Background of the invention

[0002] Controlled ventilation of buildings is, at present, more important than before, in view of e.g. habitability, energy saving, and preventing moisture from damaging structures. In many cases, buildings are equipped with a mechanical exhaust system for removing air from the rooms of the building and for conveying the removed air, for example, outdoors, either directly or via a heat recovery unit. Supply air, that is, replacement air, can be introduced into the rooms via replacement air valves and increasingly by means of air supply devices. Typically, in air supply devices, replacement air is introduced from atmospheric air by means of an air supply unit to an inlet air duct system. In the inlet air duct system, replacement air is distributed into supply air valves placed in different rooms and normally located in walls of the rooms, relatively close to the ceiling. The replacement air valve thus comprises an inlet which is connected to the inlet air duct system, so that the replacement air can flow into the flow duct in the supply air valve. The flow channel guides the replacement air via a louver on the indoor side into the room. The louver can be, for example, a perforated plate which simultaneously acts as a kind of a screen.

[0003] A drawback in mechanical supply air systems of prior art is the fact that the relatively high sound caused by the supply air unit can be carried via the inlet air duct system to the supply air valve and further into the room. Thus, the supply air system can be found disturbing, and in some cases the supply air system can even be turned off in order to stop the disturbing noise.

Brief summary of the invention

[0004] It is an aim of the present invention to provide an improved supply air valve, by which the disturbing noise caused by the supply air unit can be significantly reduced. The present invention is based on the idea of providing the flow channel of the supply air valve with a damping member and a control member, by means of which it is possible to control the quantity of air introduced into a room via the supply air valve and simultaneously to suppress noise carried via the inlet air duct system to the supply air valve. To put it more precisely, the supply air valve according to the present invention is primarily characterized in that the supply air valve further comprises a damping member, whose at least one wall is oblique to the direction of flow of incoming air supplied via the inlet, and a control member, by means of which the size of the flow area between the damping member and the control member is arranged to be adjusted.

[0005] The present invention shows remarkable advantages over solutions of prior art. When applying the supply air valve according to the invention, it is possible to absorb disturbing noise carried via the inlet air duct system, which improves e.g. habitability.

Description of the drawings

[0006] In the following, the present invention will be described in more detail with reference to the appended drawings, in which

Fig. 1

shows a top view of a supply air valve according to an advantageous embodiment of the invention,

Fig. 2

shows the supply air valve according to Fig. 1, seen from the direction of the inlet,

Fig. 3

shows the supply air valve according to Fig. 1, seen from the direction of a louver, the louver being removed,

Fig. 4a

shows a supply air valve according to a first embodiment, in a cross-sectional view in the direction A-A of Fig. 3,

Fig. 4b

shows a supply air valve according to a second embodiment, in a cross-sectional view in the direction A-A of Fig. 3,

Fig. 4c

shows a supply air valve according to a third embodiment, in a cross-sectional view in the direction A-A of Fig. 3,

Fig. 4d

shows a supply air valve according to a fourth embodiment, in a cross-sectional view in the direction A-A of Fig. 3,

Fig. 4e

shows a supply air valve according to a fifth embodiment, in a cross-sectional view in the direction A-A of Fig. 3,

Fig. 5a

shows a supply air valve according to a first embodiment, in a cross-sectional view in the direction B-B of Fig. 3,

Fig. 5b

shows a supply air valve according to a second embodiment, in a cross-sectional view in the direction B-B of Fig. 3,

Fig. 6

shows the supply air valve according to Fig. 1, seen from the direction of one end,

Fig. 7

shows a reduced view of air flows via a supply air valve when a supply air valve according to an advantageous embodiment of the invention is applied,

Fig. 8

shows another cross-sectional shape of a louver,

Fig. 9a

shows the louver of Fig. 8 seen from above, and

Fig. 9b

shows the louver of Fig. 8 seen from below.

Detailed description of the invention

[0007] Figure 1 shows a top view of a supply air valve 1 according to an advantageous embodiment of the invention. The supply air valve 1 comprises an inlet 2, through which replacement air can be introduced from an inlet air duct system 3 (Fig. 7) to the flow channel 4 of the supply air valve 1. One example of the flow channel 4 of the supply air valve can be seen e.g. in Fig. 5a. Further, the supply air valve 1 comprises a louver 5 which is used e.g. as a screen hiding the components inside the supply air valve at least partly and guiding the replacement air from the flow channel 4 of the supply air valve 1 to the side of the room. The louver 5 comprises a perforation 6 which is provided in the louver advantageously so that the air flow is directed at least partly diagonally upwards when entering the room. Furthermore, the supply air valve 1 comprises a damping member 9 and a control member 10.

[0008] Figure 2, in turn, shows the supply air valve of Fig. 1 seen from the direction of the inlet 2.

[0009] Figure 3 shows the supply air valve according to Fig. 1, seen from the direction of the louver, the louver being removed. Thus, the above-mentioned control member 10 and the damping member 9 are at least partly visible in this embodiment. The more detailed structure of the supply air valve according to the invention is shown in the cross-sectional views of 4a to 5b. The cross-sectional directions used in these figures are indicated with the letters A-A and B-B in Fig. 3.

[0010] Figure 4a shows the cross-section of a supply air valve according to a first embodiment of the invention in the direction A-A, and Fig. 4b, correspondingly, shows the cross-section of a supply air valve according to another embodiment in the direction A-A. The damping member 9 is a design with a diagonal or corresponding cross-sectional shape, where the thickness of the wall 9a of the damping member is not constant. This diagonal or corresponding design is advantageously placed in that part of the damping member 9 which forms a flow wall for the replacement air flow, as can be seen e.g. from the flow examples of Figs. 5a and 5b. The diagonality changes the cross-sectional area, shape and/or size of the flow channel for replacement air compared with the cross-section of the inlet air duct system 19 at the joint of the inlet air duct system 19 and the inlet 2 of the supply air valve. In Fig. 4a, the thickness decreases in the direction of the air flow, which in the embodiment of Fig. 4a is from below upwards. Correspondingly, in the example of Fig. 4b, the thickness of the damping member increases in the direction of the air flow. Other cross-sectional shapes are also possible, in which the thickness of the wall of the damping member is not constant in the direction of the air flow. Possible alternatives include convex and concave shapes. Various triangular and polygonal shapes are also feasible. Moreover, the damping member 9 does not need to be completely inside the inlet 2, but part of it can also extend outside the inlet 2.

[0011] In the direction transverse to the direction of the air flow, the shape of the damping member 9 advantageously resembles the shape of the inner surface of the inlet 2. In the example of Fig. 2, the outer rim of the damping member 9 is substantially circular. In this example, the inner rim of the damping member 9 is also substantially circular. Other shapes are also feasible, if the inlet 2 is not circular. Examples include a rectangle and its special case of a square.

[0012] Figure 5a shows the cross-section of a supply air valve according to a first embodiment of the invention in the direction B-B of Fig. 3, that is, in the direction perpendicular to the direction A-A. The flow channel 4 of the supply air valve 1 is visible in this figure. The flow channel 4 is delimited by the damping member 9, the control member 10, a second damping member 11, and third damping members 12. The air flow entering via the inlet 2 and through an opening between the damping member 9 and the control member 10 is guided by the second damping member 11 which deflects it substantially into the volume between the bottom part 13 of the supply air valve 1 and the second damping member 11, advantageously at least partly towards the edges of the supply air valve 1. Moreover, third damping members 12 are provided at the ends of the supply air valve 1 for deflecting the air flow further towards the perforation 6 of the louver 5. Through the openings 7 of the perforation 6 of the louver, replacement air is introduced into the room. By the placement and/or the design of the openings of the perforation 6 of the louver, it is possible to influence, at least partly, the direction of the replacement air when it enters the room. Most of the openings are advantageously placed in that part of the louver which is facing up in the service position of the supply air valve. In an example, openings are only provided above half-way of the louver 5, and in another example, openings are provided above the lowermost third of the louver, the lowermost third being without openings. Consequently, the louver 5 is used as a kind of a means for directing the air flow.

[0013] Figure 7 shows, in a reduced manner, air flows in connection with a supply air valve 1 according to an advantageous embodiment of the invention. Replacement air is supplied from the air supply unit 18 to the inlet air duct system 19 and further into the inlet 2 of the supply air valve 1. From the inlet 2, replacement air flows into the flow channel 4 and further through openings 7 of the perforation of the louver into the room 20. The air flow directed diagonally upwards also generates a kind of a suction below the supply air valve 1 so that the air flow is intensified in the vicinity of the supply air valve 1, below the level of the supply air valve 1, thereby enhancing the mixing of replacement air with the air in the room and generating a kind of air circulation in the room. This phenomenon is illustrated with arrows 8 in Fig. 7. As can be seen from Fig. 7, the air flow rising from a lower level in the vicinity of the supply air valve 1 can be turbulent to some extent when it is mixed with the replacement air coming in via the supply air valve 1.

[0014] Figure 5b shows the cross-section of a supply air valve according to a second embodiment, in the direction B-B of Fig. 3. The difference to the embodiment of Fig. 5a is primarily the fact that the diagonality of the damping member 9 is reverse to that of the damping member of Fig. 5a, as already disclosed in connection with Figs. 4a and 4b.

[0015] We shall now describe the operation of the control member 10 in the supply air valve 1 according to the invention. Replacement air introduced via the inlet 2 can enter the flow channel 4 through a gap between the damping member 9 and the control member 10. The position of the control member 10 can be changed, if necessary, so that the gap between the damping member 9 and the control member 10 becomes either larger or smaller. With this adjustment, it is possible to affect, among other things, the quantity of replacement air entering the room via the supply air valve 1. In the embodiment of Figs. 4a and 5a, the air flow is increased, when the control member is moved in the direction of flow of replacement air, that is, upwards in the figures. In a corresponding manner, by moving the control member in the reverse direction, the air flow can be decreased. In the examples of Figs. 4b and 5b, the adjustment is reverse.

[0016] The movement of the control member 10 can be made, for example, by rotating the mounting shaft 15 of the control member. This mounting shaft may be provided with a threading which fits a threading (not shown) in a fastening means 16 for the control member in the supply air valve 1. At the end of the mounting shaft, there may be, for example, a groove or two crosswise grooves, wherein the adjustment can be made, for example, by inserting the head of a screwdriver in the groove and turning the screwdriver in the desired direction. For performing the adjustment as reliably as possible, a pressure sensor or a flow sensor can be placed in the perforation 6. The pressure sensor can be used for measuring the pressure difference between the room and the inlet air duct, whereby the quantity of air flowing through the supply air valve 1 can be calculated, for example, by means of the so-called k factor determined for the supply air valve. A useful formula in this context is

where q is the quantity of air, k is a valve specific constant, and Δp is the pressure difference.

[0017] The control member 10 can also be equipped with an air guide 14, as shown in Fig. 4c. This air guide 14 can reduce the air flow resistance in the inlet 2 and can also improve the noise suppression properties. The air guide 14 can be made of, for example, a noise reduction material.

[0018] In the examples described above, the diameter of the inner surface of the pipe constituting the inlet 2 was substantially constant, wherein the diameter of the outer surface of the damping member 9 is preferably constant. However, the invention is not restricted solely to such inlets, but the diameter of the inner surface can also be variable in the direction of flow of replacement air. Thus, the diameter of the outer surface of the damping member 9 can also vary accordingly, unless the flow of replacement air between the inlet 2 and the damping member 9 is prevented or reduced in another way.

[0019] For facilitating the cleaning of the supply air valve, the control member 10 can be made removable. This can be implemented, for example, in such a way that a supporting ribbon 17 is not fastened to the bottom part 13 but is left unfastened. In this case, the control member 10 can be kept in position, when the supply air valve 1 is in use, by arranging the length of the supporting ribbon 17 equal to or slightly greater than the outer dimension of the louver 5 in the cross-sectional direction A-A, and providing the louver with small slots 22 (Fig. 1) whose size and shape advantageously correspond to the cross-sectional shape and size of the supporting ribbon. Thus, the supporting ribbon 17 is placed in these slots 22 and remains in position, thanks to the louver.

[0020] Figures 4a, 4b and 4c show a possible cross-sectional shape of third damping pieces, whose upper edge corresponds substantially to the cross-sectional shape of the inner surface of the louver 5, so that air cannot flow substantially between the third damping member 12 and the louver. On the other hand, if the louver 5 has relatively air-tight end walls 21, as shown in Figs. 5a and 5b, the cross-sectional shape of the third damping members 12 can deviate to some extent from the shape of the inner surface of the louver 5.

[0021] Figures 4d and 4e show yet another advantageous embodiment, in which the cross-sectional shapes of the damping member 9 and the control member 10 are at least partly curved. For example, the surface of the damping member 9, which directs the air flow entering the replacement air valve, is curved so that the thickness of the damping member 9 first increases and then at some point decreases again in the imaginary direction of the air flow. In this embodiment, the shape of this surface thus corresponds substantially to the curve of a circle or an ellipse. Similarly, the surface of the control member 10 can be substantially convex in the direction of incoming air flow, as shown in Figs. 4d and 4e. Such curved shapes may reduce the air flow resistance and improve the noise suppressing properties of the replacement air valve.

[0022] It is obvious that the replacement air valve can also be implemented as a combination of different embodiments, for example in such a way that the damping member 9 is like that shown in Figs. 4d and 4e, and the control member 10 is, for example, like that shown in Fig. 4b.

[0023] Figure 8 shows yet another possible cross-sectional shape of the louver 5. In this example, the louver 5 has two angles which divide the outer surface of the louver 5 into three parts, but there can also be more angles. In this embodiment, the openings of the perforation are advantageously formed in the second 5a and third 5b parts of the louver 5 only. Figure 9a shows yet the louver of Fig. 8 seen from above, and Fig. 9b shows the louver of Fig. 8 seen from below.

[0024] The louver 5 can be fastened to the bottom part 13 of the supply air valve by, for example, one or more screws, some kinds of claw arrangements, or the like.

[0025] The present invention is not limited to the above-presented embodiments, but it can be modified within the scope of the appended claims.

Claims

1. A supply air valve (1) with an inlet (2) for introducing replacement air into the flow channel (4) of the supply air valve, and an air flow directing element (5) for directing the air introduced into the flow channel (4) of the supply air valve into a room, characterized in that the supply air valve (1) also comprises a damping member (9), whose at least one wall is oblique to the direction of flow of supply air flowing via the inlet (2), and a control member (10), by means of which the flow area left between the damping member (9) and the control member (10) is arranged to be adjusted.

2. The supply air valve (1) according to claim 1, characterized in that the thickness of the wall decreases in the direction of flow of replacement air.

3. The supply air valve (1) according to claim 1, characterized in that the thickness of the wall increases in the direction of flow of replacement air.

4. The supply air valve (1) according to claim 1, 2 or 3, characterized in that the damping member (9) is placed in connection with the inlet (2).

5. The supply air valve (1) according to claim 4, characterized in that the damping member (9) is placed on the inner surface of the inlet (2).

6. The supply air valve (1) according to any of the claims 1 to 5, characterized in that the damping member (9) is made of a noise reduction material.

7. The supply air valve (1) according to any of the claims 1 to 6, characterized in that the air flow directing element (5) comprises a louver (5) for guiding the flow of replacement air coming from the flow channel (4) of the supply air valve into a room (20).

8. The supply air valve (1) according to claim 7, characterized in that the louver (5) further comprises a second damping member (11) which constitutes at least one wall of the flow channel (4) and is arranged to direct the replacement air flow coming via the flow area between the damping member (9) and the control member (10) towards the edges of the supply air valve (1).

9. The supply air valve (1) according to claim 7 or 8, characterized in that the louver (5) comprises a perforation (6) for guiding the flow of replacement air coming from the flow channel (4) of the supply air valve into a room (20) diagonally upwards.

10. The supply air valve (1) according to claim 9, characterized in that the louver (5) further comprises one or more third damping members (12) arranged to direct the replacement air flow guided by the second damping member (9) towards the perforation of the supply air valve (1).

Drawing