Air damper for an air-conducting housing, in particular for a motor vehicle air conditioning system

Abstract

The present invention relates to an air damper (20) for an air-conducting housing (11), as well as to an air-conducting housing (11) and an air distributor (10) having such an air damper (20). The air damper (20) according to the invention comprises a first air guide surface (21A) and a second air guide surface (21B), which are oriented in opposite directions, and a pivoting device (23) by means of which the air damper (20), when installed as intended in an air-conducting housing (11), can be brought into at least a first pivot position (27A) and a second pivot position (27B) altered by a pivot angle. The air damper (20) according to the invention is characterized in that an intermediate space (24) is provided between the first air guide surface (21A) and the second air guide surface (21B), which intermediate space has a hollow volume (25), and the first air guide surface (21A) comprises a sound-absorbing partial region (26) which covers the hollow volume (25).

Description

[0001] The present invention relates to an air flap for an air-conducting housing and a housing with such an air flap, in particular for automotive applications.

[0002] Automotive air conditioning systems comprise one or more air-conducting housings in which various partial air flows can be directed in specific directions or areas using air flaps. In addition to the main air conditioning unit, which typically has one or more air filters for cleaning and one or more heat exchangers to regulate the temperature of the air flow, auxiliary air conditioning units, such as amplifiers or rear air conditioning units, are also known, which have the simplest possible design. Installation space is limited both in the main air conditioning unit and, in particular, in smaller auxiliary air conditioning units. This is why flat air ducts, on the one hand, increase the risk of unwanted noise. On the other hand, this noise is difficult to compensate for with compensating volumes due to this compact design.

[0003] Another problem with a more compact design is that the deflection angle of the air flow may be very large, resulting in inhomogeneities in the air flow that cannot be sufficiently neutralized due to the short running distance in the air-conducting housing.

[0004] It is the object of the present invention to improve air-conducting housings with regard to the above-mentioned problem, i.e. to provide acoustic and flow-homogenizing measures which can be used when there is little available installation space.

[0005] This object is achieved according to the invention by an air damper having the features of claim 1, by an air-conducting housing having the features of claim 6, and by an air distributor having the features of claim 9. Advantageous embodiments and further developments emerge from the appended claims.

[0006] The air damper according to the invention for an air-guiding housing comprises a first air guide surface and a second air guide surface, which are oriented in opposite directions. The two air guide surfaces can also be referred to as the front and rear of the air damper, without being fixed to a surface normal aligned at exactly 180° to each other. The air damper according to the invention further comprises a pivoting device by means of which the air damper, when installed as intended in an air-guiding housing, can be brought into at least a first pivot position and a second pivot position changed by a pivot angle. The air damper according to the invention is characterized in that an intermediate space is provided between the first air guide surface and the second air guide surface, which intermediate space has a hollow volume, wherein the first air guide surface comprises a sound-absorbing partial region which covers the hollow volume.By utilizing the flap geometry, i.e. the space between the two air guide surfaces, a sound absorption space is created which reduces unwanted noise from the passing air flow.

[0007] A pivoting device within the meaning of the invention comprises any device known to those skilled in the art that is suitable for pivoting an air flap into two different positions. It typically comprises a pivot axis, via which the pivot angle is defined. Such a pivot axis can be arranged, in particular, at the edge, but also at another position on the air flap, e.g., centrally. Pivoting can also be provided in other ways, e.g., via a frame or a lever construction, in which an imaginary pivot axis does not remain stationary during the pivoting process.

[0008] According to one embodiment, the sound-absorbing portion comprises a fleece (also called nonwoven, synthetic fiber fur, or knitted fur). The fleece can be provided integrally in the first air guide surface or as an insert that is inserted, glued, or otherwise attached over an opening in the hollow volume provided in the first air guide surface.

[0009] Optionally, the second air guide surface can be designed to be dimensionally stable and soundproof. This allows the cavity aligned with the first air guide surface to occupy virtually the entire thickness of the air flap. The second air guide surface can also be convexly curved, so that the hollow volume between the first air guide surface and the second air guide surface has a convex shape. The first air guide surface is in particular flat or, if necessary, slightly convex or concave. If it is concave, however, it is less concave than the second side, which is convex, so that in any case a lens-shaped thickening for the hollow volume is created between the two air guide surfaces.

[0010] In a simple but expedient embodiment, it is provided that the pivoting device has a pivot axis which is arranged at the end of the first air guide surface and the second air guide surface, so that they can be pivoted along a common fixed edge from the first pivot position to the second pivot position.

[0011] According to the invention, the air-guiding housing comprises a previously described air flap, an air inlet, an air switch in fluid communication with the air inlet, and a first and a second air outlet, which separate from one another downstream of the air switch. The air-guiding housing is characterized in that the air flap is positioned by means of the pivoting device in the region of the air switch such that in a first pivoting position the air inlet can be brought into fluid communication with the first air outlet, and in a second pivoting position the air inlet can be brought into fluid communication with the second air outlet. In the first pivoting position, the first air guide surface can be aligned as a wall that limits the air flow, and in the second pivoting position the second air guide surface can be aligned as a wall that limits the air flow.This creates a first air duct to the first air outlet in the first pivoting position and a second air duct to the second air outlet in the second pivoting position.

[0012] Advantageously, the air damper is used in such a way that the air flow in the area of the air deflector is deflected to the first air outlet by an angle between 60° and 120°. In other words, the sound-absorbing section is installed in a section of the first air duct where the large deflection angle can increase noise generation.

[0013] Alternatively or additionally, the air damper is used in such a way that the air flow in the area of the air diverter is deflected to the second air outlet by an angle of less than 30°, preferably being passed on essentially straight. In other words, the dimensionally stable, rigid section on the second air guide surface is inserted in an area of the second air duct in which the air flows straight ahead. Depending on the compact design of the air-guiding housing, the possibly convex shape can also be exploited to accelerate the air and homogenize the flow through the Coanda effect. In this way, the air-guiding housing can be designed to be very flat.

[0014] According to the invention, an air distributor for a motor vehicle air conditioning system can be constructed with an air-conducting housing configured in this way, wherein a fan is arranged between the air inlet and the air switch. Advantageously, the air flow direction at the air inlet runs essentially parallel to the air flow direction at the second air outlet, whereas the air flow direction at the first air outlet runs essentially perpendicular thereto.

[0015] The invention will now be described by means of embodiments and with reference to the Fig. 1 to 6 are explained in more detail. The Fig. 1 shows an air distributor which can be used as part of a motor vehicle air conditioning system, the Fig. 2 shows the air flow pattern in an air distributor according to Fig. 1 with a state-of-the-art air damper, the Fig. 3 to 5 show different views of an air damper according to an embodiment of the invention and the Fig. 6 to 8 show top views of the opened housing of the air distributor from the Fig. 1, with an air damper according to the invention according to the Fig. 3 to 5 in different swivel positions.

[0016] In the Fig. 1 shows an air distributor 10, which is particularly suitable for a rear unit for a motor vehicle air conditioning system. Such air distributors 10, also known as boosters, are typically installed in the front seats or near the B-pillar of a motor vehicle and receive pre-conditioned air from the front air conditioning unit via an air inlet 12, as is known to those skilled in the art (not shown). By means of the air-conducting housing 11, the air can be distributed via several air outlets for the targeted air conditioning of various rear areas, in this case via the air outlet 14A as a foot outlet and via the air outlet 14B towards the side area near the B-pillar. The air distributor has a fan 15 and a stepper motor 16, which will be discussed in more detail below.

[0017] The uniform and quiet air distribution in such air distributors 10 presents several technical challenges for the expert. Firstly, the compact design and the resulting flat air ducts with sometimes tight curve radii lead to undesirable noise. Furthermore, the provision of a homogeneous air flow at the air outlets is not possible everywhere, as has been explained with reference to the Fig. 2 is briefly explained. Depending on the design specifications from the example shown, the air flow L1 at the air outlet 14B may have a dead zone 17, so that the full width of the air outlet 14B cannot be used effectively.

[0018] In the Fig. 3 to 5 show various views of an air damper 20 according to an embodiment of the invention. The air damper 20 is shown from both inflow sides and in a side view. It has a first air guide surface 21A and a second air guide surface 21B, which are oriented in opposite directions, so that when air flows against one of the two air guide surfaces, the other is oriented to the rear with respect to the air flow. The basic shape of the damper body is a substantially flat rectangular frame 22, on one edge of which (the fixed edge 22A) a pivot axis 23 is provided (a small extension 22B can also be provided for sealing). When the air damper 20 is installed as intended in the air-guiding housing 11, the air damper 20 can be pivoted about the pivot axis 23 so that it can be exposed to air flow from different directions.

[0019] Between the first air guide surface 21A and the second air guide surface 21B, an intermediate space 24 is provided, which has a hollow volume 25 with an opening in the direction of the first air guide surface 21A. The first air guide surface 21A further has a sound-absorbing portion 26 in the form of a fleece covering the hollow volume 25. The fleece is attached to the air guide surface in a suitable manner, e.g., glued or inserted into holders (not shown).

[0020] The second air guide surface 21B is designed to be dimensionally stable and sound-impermeable, typically from a hard plastic (in the exemplary embodiment, from polypropylene PP-TD40), which can also be used for the rest of the air flap 20. The material thickness or wall thickness of the flap is typically 1 - 5 mm, in the exemplary embodiment approximately 2 - 2.5 mm. Towards the center of the second air guide surface 21B, it is convexly curved (i.e., protrudes outwards in an arc shape), so that a plano-convex hollow volume 24 is formed between the first air guide surface 21A and the second air guide surface 21B.

[0021] With reference to the Fig. 6 to 8, the inventive use of the air damper 20 according to the Fig. 3 to 5 in the air-conducting housing 11 of the air distributor 10 according to Fig. 1. Shown in the Fig. 6 and Fig. 8 are plan views of the housing of the air distributor 10 in two different pivot positions, a first pivot position 27A and a second pivot position 27B changed by a pivot angle α. In the Fig. 7 is a detailed view of the Fig. 6 around the pivot axis 23. Without going into detail, intermediate positions between the first pivot position 27A and the second pivot position 27B are also possible.

[0022] Between the air inlet 12 and the air switch 13 is the blower 15 (see Fig. 1) to support or maintain the air flow provided by the front air conditioning unit. The air diverter 13 is in fluid communication with the air inlet 12 and, depending on the pivot position 27A, 27B, can bring the air inlet 12 into fluid communication with one of the two air outlets 14A, 14B arranged downstream of the air diverter 13. The air flow direction of the air flow L3 at the air inlet 12 runs essentially parallel to the air flow direction of the air flow L3 at the second air outlet 14B, while the air flow direction of the air flow L2 at the first air outlet 14A runs essentially perpendicular thereto.

[0023] According to the invention, the air flap 20 is positioned by means of the pivot axis 23 in the region of the air switch 13 such that in the first pivot position 27A the air inlet 12 can be brought into fluid communication with the first air outlet 14A and in the second pivot position 27B the air inlet 12 can be brought into fluid communication with the second air outlet 14B. In the first pivot position 27A the air flow thus flows onto the first air guide surface 21A, and in the second pivot position 27B the air flow flows onto the second air guide surface 21B. The stepper motor 16 (see Fig. 1) for adjusting the pivot angle of the air flap 20 is arranged on the outside of the air-guiding housing 11 near the pivot axis 23.

[0024] In the area of the air deflector 13, the air flow is deflected to the first air outlet 14A by an angle of 90°. By flowing onto the sound-absorbing portion 26, the air damper 20 provides acoustic damping.

[0025] In the area of the air diverter 13, the air flow is directed essentially straight to the second air outlet 14B (deflection angle ≈ 0°). The convex surface guidance of the second air guide surface 21B causes air acceleration and flow homogenization in the end area around the second air outlet 14B.

[0026] The air damper 20 according to the invention allows for a very compact design of the air distributor 10. The acoustic damping on the first air guide surface 21A allows for a deflection of the air flow over a short distance. The convex shape of the second air guide surface 21B allows for improved homogenization of the air flow, so that even with a flat design and despite interference areas (the position of the stepper motor 16 near the air outlets 14A, 14B), noise generation is kept low and air distribution is uniform. REFERENCE SYMBOL 10 air distributors 11 air-conducting housing 12 Air inlet 13 Air switch 14 A, B air outlets 15 blowers 16 Stepper motor 17 Dead zone 20 air flap 21 A, B air guide surfaces 22 frames 22 A fixed edge 22B Appendage 23 Swivel axis 24 space 25 hollow volume 26 sound-absorbing section, fleece 27 A,B swivel positions L1 - L3 air currents α swivel angle

Claims

[1] Air damper (20) for an air-conducting housing (11), comprising - a first air guide surface (21A) and a second air guide surface (21B) oriented in opposite directions, and - a pivoting device (23) by means of which the air flap (20) can be brought into at least a first pivoting position (27A) and a second pivoting position (27B) changed by a pivoting angle when installed as intended in an air-conducting housing (11), characterized by , that - an intermediate space (24) is provided between the first air guide surface (21A) and the second air guide surface (21B), which space has a hollow volume (25), and - the first air guide surface (21A) comprises a sound-absorbing partial area (26) which covers the hollow volume (25). [2] Air damper (20) according to claim 1, characterized by that the sound-absorbing portion (26) comprises a fleece. [3] Air damper (20) according to claim 1 or 2, characterized by that the second air guide surface (21B) is dimensionally stable and sound-impermeable. [4] Air damper (20) according to one of the preceding claims, characterized by that the second air guide surface (21B) is convexly curved, so that the hollow volume (25) between the first air guide surface (21A) and the second air guide surface (21B) has a convex shape. [5] Air damper (20) according to one of the preceding claims, characterized by that the pivoting device has a pivot axis (23) which is arranged at the end of the first air guiding surface (21A) and the second air guiding surface (21B), so that these can be pivoted along a common fixed edge (22A) from the first pivot position (27A) into the second pivot position (27B). [6] Air-conducting housing (11) with an air flap (20) according to one of the preceding claims, comprising an air inlet (12), an air switch (13) in fluid communication with the air inlet (12) and a first air outlet (14A) and a second air outlet (14B) which separate from each other downstream of the air switch (13), characterized by , that - the air flap (20) is positioned by means of the pivoting device (23) in the region of the air switch (13) such that in a first pivoting position (27A) the air inlet (12) can be brought into fluid communication with the first air outlet (14A) and in a second pivoting position (27B) the air inlet (12) can be brought into fluid communication with the second air outlet (14B), - wherein in the first pivot position (27A) the first air guide surface (21A) can be aligned as a wall limiting the air flow and in the second pivot position (27B) the second air guide surface (21B) can be aligned as a wall limiting the air flow. [7] Air-conducting housing (11) according to claim 6, characterized by that the air flow in the area of the air switch (13) is deflected to the first air outlet (14A) by an angle in the range between 60° and 120°. [8] Air-conducting housing (11) according to claim 6 or 7, characterized by that the air flow in the region of the air switch (13) is deflected to the second air outlet (14B) by an angle of less than 30°, preferably being passed on essentially straight. [9] Air distributor (10) for a motor vehicle air conditioning system with an air-conducting housing (11) according to one of claims 6 to 8, wherein a fan (15) is arranged between the air inlet (12) and the air switch (13). [10] Air distributor (10) for a motor vehicle air conditioning system according to claim 9, wherein the air flow direction at the air inlet (12) is substantially parallel to the air flow direction at the second air outlet (14B), and the air flow direction at the first air outlet (14A) is substantially perpendicular thereto

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