Device for generating an air flow for a motor vehicle

Abstract

A device for generating an air flow for a motor vehicle, the device comprising a housing (8) defining a passage (50) for the air flow at an outlet of the pulse generator (16) and a tangential pulse generator (16) having an axis of rotation extending in a so-called longitudinal direction, the device comprises at least one acoustic barrier (52, 52 ') located at one end of the channel (50) in the longitudinal direction.

Description

Technical Field

[0001] The invention relates to a device for generating an air flow for a motor vehicle. The air flow is intended to be diffused in particular into the passenger compartment of the vehicle. Background Art

[0002] Ventilation, heating, and / or air conditioning devices are known in the art that direct the airflow toward the passengers behind the driver and / or toward the front passengers. It is also known to locate these devices in the roof of the passenger compartment, where they are concealed. Given the limited available height, these devices include tangential blowers to generate the airflow. These blowers have a small radial footprint, which facilitates their placement in a small volume, and can, conversely, extend axially over a large area, allowing the generated airflow to flow across the entire width of the passenger compartment.

[0003] Despite their various advantages, it has been found that these devices generate parasitic noise which is detrimental to passenger comfort. Summary of the Invention

[0004] The object of the present invention is to alleviate at least some of the above-mentioned disadvantages and, for this purpose, the invention proposes a device for generating an air flow for a motor vehicle, said device comprising a housing defining a channel for the air flow at the outlet of the blower and a tangential blower, said housing having an axis of rotation extending in a direction referred to as the longitudinal direction, said device comprising at least one sound insulation screen at one end of said channel in said longitudinal direction.

[0005] The applicant has determined that the parasitic noise generated by this type of device originates primarily from the turbulence of the air flow at the outlet of the blower, near the longitudinal ends of the flow channel. One or more acoustic barriers positioned in this manner according to the invention at this location make it possible to disrupt the turbulence and thus limit its noise nuisance.

[0006] According to various additional features of the present invention, which may be employed together or separately, to form numerous embodiments of the invention:

[0007] - the sound insulation screen comprises foam blocks,

[0008] - the sound insulation screen comprises a partition,

[0009] - the device comprises a further sound insulation barrier at the other end of the channel in the longitudinal direction,

[0010] - the housing comprises two walls defining opposite ends of the channel in the longitudinal direction,

[0011] - said wall is oriented substantially transversely to said longitudinal axis, in particular orthogonally to said longitudinal axis,

[0012] - the acoustic screen is positioned against the wall,

[0013] - said wall comprises a poka-yoke for positioning said acoustic screen,

[0014] - the minimum distance in the direction of the air flow between the acoustic screen(s) on the one hand and the blower on the other hand is at most 5 cm, preferably at most 2 cm, or even 1 cm,

[0015] - said housing defines a blower housing nose extending in said longitudinal direction at an outlet of said blower,

[0016] - the sound insulation screen is positioned close to a longitudinal side of the duct opposite to the longitudinal side of the duct connected to the nose of the blower housing,

[0017] - the extension of the acoustic barrier is at most half the dimension of the channel in a direction orthogonal to the direction of air flow and to the longitudinal direction, referred to as the height of the channel,

[0018] - the extension of the acoustic barrier in the longitudinal direction is at most 2 cm, or even 1 cm,

[0019] - said blower has a longitudinal extent substantially the same as the longitudinal dimension of said channel,

[0020] - the blower comprises a stack of wheels along the longitudinal axis, the wheels being equipped with blades such that an air flow is sucked in at the inlet of the blower and discharged at the outlet,

[0021] - each of said wheels is equipped with blades having a regularly spaced angular pitch from one blade to the next,

[0022] - the blades are offset by half the pitch from one wheel to the next,

[0023] - the blower is located in a recess defined by the housing,

[0024] - the device comprises a heat exchanger for cooling and / or heating the air flow,

[0025] - the exchanger is located in the recess,

[0026] - the exchanger is located upstream of the blower in the direction of flow of the air stream,

[0027] - the device comprises one or more diffusers at the outlet of the channel,

[0028] - the diffusers are located substantially in the same plane,

[0029] - said plane extends parallel to said longitudinal direction,

[0030] - The device is configured to be housed in a roof of a passenger compartment of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The invention will be better understood and other objects, details, features and advantages of the invention will become more clearly apparent from the following detailed explanatory description of at least one embodiment of the invention, provided by way of purely illustrative and non-limiting example, with reference to the accompanying schematic drawings, in which:

[0032] Figure 1 An example of a device according to the invention is shown schematically in longitudinal section;

[0033] Figure 2 The diagram from Figure 1 A cross-sectional view of a device showing only the housing and the blower of the device;

[0034] Figure 3 A cross-sectional view of the device from the preceding figures is schematically shown. DETAILED DESCRIPTION

[0035] like Figure 1 As shown, the invention relates to a device 1 for generating an air flow for a motor vehicle.

[0036] The device 1 is configured to be housed, for example, in the roof 2 of the passenger compartment of the vehicle. It is intended to direct the air flow particularly toward the rear passengers of the vehicle, that is, toward the passengers in one or more rows of seats located behind the driver and the front passengers of the vehicle. It is positioned, for example, between the cladding wall 4 of the roof 2 and the upper surface 6 of the vehicle body.

[0037] The device includes a housing 8. The housing 8 is configured to allow air flow to be drawn in at one or more air inlet openings 30 in the direction of the arrows indicated at 32. The housing 8 is also configured to allow air flow to be discharged through one or more air outlet openings 34 in the direction of the arrows indicated at 36.

[0038] Said housing 8 is for example fixed to said upper surface 6 of the vehicle body, in particular by means of a first fastening rail 10 and / or by means of a second fastening rail 14 , in this case located at the centre pillar 1 of said vehicle body.

[0039] The device also includes a tangential blower 16. The blower has an axis of rotation 18 extending in a direction referred to as the longitudinal direction. The figure shows an orthogonal coordinate system. It comprises an X axis, a Y axis, and a Z axis. In this case, the X axis is oriented in a direction connecting the front and rear faces of the vehicle, the Y axis is perpendicular to the plane of the figure and oriented in a direction connecting the left and right sides of the vehicle, and the Z axis is oriented in a vertical direction. It can be seen that the longitudinal direction corresponds to the Y direction, which is perpendicular to the plane of the figure. Thus, in this case, the blower 16 extends transversely into the passenger compartment of the vehicle.

[0040] The blower 16 is configured to generate a two-dimensional flow, that is, with streamlines remaining in planes perpendicular to the longitudinal axis 18. In other words, in this case, the streamlines lie in planes oriented along the X and Z axes, parallel to the plane of the drawing.

[0041] The device preferably also includes a heat exchanger 40 for cooling and / or heating the air flow. The heat exchanger 40 is configured to be passed through by a refrigerant fluid for exchanging heat with the air flow. It comprises, for example, a heat exchange bundle 42 provided with tubes through which the refrigerant fluid flows, and fins arranged between the tubes and through which the air flow passes. The device is typically supplied with refrigerant fluid from a main heating, ventilation, and / or air conditioning system (e.g., arranged under the dashboard of the vehicle).

[0042] The housing 8 defines a recess 44 accommodating the blower 16 and / or the heat exchanger 40. The housing 8 particularly defines a blower housing nose 45 extending in the longitudinal direction Y at the outlet of the blower, in this case at the bottom.

[0043] The heat exchanger 40 is preferably located upstream of the blower 16 in the direction of flow of the air flow. In other words, in this case, the air flow enters the housing 8 via the air inlet or inlets 30 and flows through the recess 44 by first passing through the heat exchanger 40 and then through the blower 16, before being discharged from the housing 8 via the outlet orifice or orifices 34, this being done under the action of the drive generated by the blower 16.

[0044] exist Figure 2, the blower 16 is shown in the housing 8 without the heat exchanger 40. The blower 16 comprises, for example, a stack of wheels 20 oriented along the longitudinal axis 18. The wheels 20 preferably have the same radius. Thus, the blower 16 has a substantially cylindrical configuration. The wheels 20 are provided with blades 22 such that air flow is drawn in at the inlet of the blower 16 and discharged at the outlet of the blower 16 according to the arrows 23 and 24, respectively.

[0045] The blades 22 have a small chord, for example, in the direction of rotation of the blower 16. It can be seen that the radius of the wheel 20 is much smaller than the extension of the stack of wheels 20 along the longitudinal axis 18.

[0046] The blades 26 of the same one of the wheels 20 preferably have a regular angular spacing pitch from one blade to the next. The blades 26 are advantageously offset from one wheel 20 to the next by half a spacing pitch.

[0047] Still Figure 2 , it can be seen that the housing 8 defines a channel 50 for the air flow at the outlet of the blower 16. The channel 50 extends in the flow direction of the air flow between the blower 16 and the one or more outlet openings 34. It has a larger dimension in the direction of the longitudinal axis 18. It has two opposite longitudinal sides, in this case a lower longitudinal side 56 and an upper longitudinal side 58. The housing 8 also includes two walls 54, 54', which define the opposite ends of the channel 50 in the longitudinal direction Y and connect the longitudinal sides 56, 58. The walls 54, 54' are oriented substantially transversely to, in particular orthogonally to, the longitudinal axis Y, that is to say in this case in the planes X, Y.

[0048] Along one of the longitudinal sides, in this case the lower side 56 , the channel 50 is connected to the blower housing nose 45 at the end of the channel 50 opposite the air outlet aperture(s) 34 .

[0049] like Figure 3 As shown, according to the invention, the device comprises at least one acoustic barrier 52 located at one end of the passage 50 along the longitudinal direction Y. Preferably, the device comprises another acoustic barrier 52' ​​located at the other end of the passage 50 along the longitudinal direction Y. The acoustic barriers 52, 52' are not Figure 1 and 2 Shown in.

[0050] The Applicant has been able to determine that such acoustic screens 52 , 52 ′ make it possible to limit, or even eliminate, the noise generated by the device at the longitudinal ends of said channel 50 , in particular by avoiding the creation of vortices in the air flow at this level.

[0051] According to a first embodiment, the acoustic barrier 52 comprises a foam block. In a variant, the acoustic barrier 52 comprises a spacer. According to yet another embodiment, the two aforementioned variants are combined.

[0052] The acoustic barriers 52, 52' are positioned against the walls 54, 54', such as by gluing in the case of foam blocks or being integral in the case of dividers. Although not the case in the illustrated embodiment, the walls 54, 54' may include poka-yoke features for positioning the acoustic barriers 52, 52' to facilitate proper positioning of the acoustic barriers 52, 52' while still remaining within the scope of the present invention.

[0053] From a dimensional point of view, the minimum distance between one or more sound insulation screens 52, 52' on the one hand and the blower 16 on the other hand is at most 5 cm, preferably at most 2 cm, or even 1 cm in the direction of the air flow. The extension of the sound insulation screens 52, 52' in the longitudinal direction Y is, for example, at most 2 cm, or even 1 cm.

[0054] The screens 52, 52' are preferably located near a longitudinal side 58 of the channel 50, opposite the longitudinal side 56 of the channel 50 connected to the blower housing nose 45. In other words, in this case, the acoustic screens 52, 52' are located close to the upper longitudinal side 58. Advantageously, they extend from the longitudinal side 58, in this case downwardly.

[0055] The extension of the sound insulation screens 52 , 52 ′ is at most half the dimension of the channel 50 in a direction referred to as the height of the channel 50 , in this case corresponding to the distance between the lower longitudinal face 56 and the upper longitudinal face 58 .

[0056] Preferably, the blower 16 has a longitudinal extent substantially identical to the longitudinal dimension of the channel 50. In other words, the spacing between the transverse walls 54, 54' of the recess 50 corresponds to the dimension of the blower 16 in the longitudinal direction Y.

[0057] In this case, the device also comprises a motor 60 for driving the blower 16. It is located in the housing 8, for example in the longitudinal continuation of the blower 16.

[0058] Reference again Figure 1 and Figure 2As can be seen, the device also includes one or more diffusers 62 at the outlet of the channel 50. The diffusers 50 are substantially located in a common plane P, which extends, for example, parallel to the longitudinal direction Y. This plane P can be oriented at a slight angle relative to the planes Y and Z, so as to allow the air flow to pass through in a downwardly directed orientation. The diffusers 62 are advantageously configured to allow the direction and / or flow rate of the air flow to be adjusted, in particular by means of hinged grilles.

Claims

1. A device for generating an air flow for a motor vehicle, said device (1) comprising a housing (8) and a tangential blower (16), said housing (8) defining a channel (50) for the air flow at the outlet of the blower (16), said blower (16) having an axis of rotation (18) extending in a direction (Y) referred to as the longitudinal direction, said device comprising at least one sound insulation screen (52, 52') located at one end of said channel (50) in said longitudinal direction (Y).

2. The device according to claim 1, wherein The sound insulation screen (52, 52') comprises a foam block.

3. The device according to any one of the preceding claims, wherein The housing (8) defines a blower housing nose (45) extending in the longitudinal direction (Y) at the outlet of the blower (16), and the sound insulation screen (52, 52') is positioned adjacent a longitudinal side (58) of the passage (50) opposite a longitudinal side (56) of the passage (50) connected to the blower housing nose (45).

4. The device according to any one of the preceding claims, wherein The acoustic screen (52, 52') extends at most half the dimension of the channel (50) in a direction orthogonal to the direction of the air flow and to the longitudinal direction (Y), referred to as the height of the channel.

5. The device according to any one of the preceding claims, wherein The extension of the sound insulation screen (52, 52') in the longitudinal direction is at most 2 cm, or even 1 cm.

6. A device according to any one of the preceding claims, wherein The minimum distance in the direction of the air flow between the sound insulation screen (52, 52') on the one hand and the blower (16) on the other hand is at most 5 cm, preferably at most 2 cm, or even 1 cm.

7. The device according to any of the preceding claims, comprising a further acoustic barrier at the other end of the channel (50) in the longitudinal direction (Y).

8. Device according to the preceding claim, wherein The housing (8) comprises two walls (54, 54') defining opposite ends of the passage (50) in the longitudinal direction (Y), the sound insulation screen (52, 52') being positioned against the walls (54, 54').

9. The device according to any one of the preceding claims, wherein The blower (16) has a longitudinal extent substantially the same as the longitudinal dimension of the passage (50).

10. The device according to any of the preceding claims, comprising one or more diffusers (62) at the outlet of the channel (50).

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