SUPPORT FOR A MOTOR AND HEATING, VENTILATION AND/OR AIR-CONDITIONING DEVICE FOR A MOTOR VEHICLE

Abstract

The motor support (16) comprises an inner ring (20) able to receive an element of the motor and an outer ring (22) able to be fastened to a housing, and a means (24) of decoupling between the two coaxial rings (20; 22) comprising a plurality of pads (46) of elastomer material that are interposed between the inner ring (20) and the outer ring (22). Each pad (46) is substantially “H”-shaped in form. The two arms (46int, 46ext; 461, 462) of the «H» are separated by a distance B. Each arm (46int, 46ext; 461, 462) has a width D measured in the radial direction. The web (46a) of the “H” has a width A measured in the orthoradial direction. The ratio A/B B is greater than or equal to 1.4, and the ratio A/D is greater than or equal to 2.

Claims

1. A motor support for a motor-fan unit of a vehicle ventilation installation, comprising: two coaxial rings including an inner ring able to accept one or more elements of the motor and an outer ring able to be fixed to a housing that forms a structural element; and a decoupling means for decoupling the two coaxial rings a plurality of blocks which are made of an elastomeric material and are interposed between the inner ring and the outer ring, each block being substantially H-shaped, the two arms of the H being separated by a distance B, each arm having a width D measured in the radial direction, the web of the H having a width A, measured in the orthoradial direction, wherein the ratio A/B is greater than or equal to 1.4 and the ratio A/D is greater than or equal to 2.

2. The motor support as claimed in claim 1, wherein each block has a thickness C measured in the direction of a common axis of the two rings, the thickness C being greater than or equal to 14 mm, and less than or equal to 16 mm, and/or the distance B is greater than or equal to 3 mm and less than or equal to 6 mm.

3. The motor support as claimed in claim 1, wherein the width A is greater than or equal to 4 mm and/or less than or equal to 20 mm.

4. The motor support as claimed in claim 1, wherein the width D of the arms of the H is greater than or equal to 2 mm and/or less than or equal to 5 mm.

5. The motor support as claimed in claim 2, wherein the web of the H has a blind hole substantially at the center of the web and extending in the direction of the common axis of the two rings.

6. The motor support as claimed in claim 2, wherein each block is flush with at least one of the two rings in the direction of the common axis of the two rings.

7. The motor support as claimed in claim 1, wherein the decoupling means comprises an elastomer ring extending between the two rings, the elastomer ring being formed as one with the blocks.

8. The motor support as claimed in claim 7, wherein the elastomer ring defines an annulus positioned radially between one of either the inner ring or the outer ring and the blocks.

9. The motor support as claimed in claim 1, wherein the elastomer material has a hardness of between 25 and 60 Shore.

10. A fan for a ventilation installation for a vehicle, comprising: a brushless electric motor; a fan impeller, rotationally driven by the electric motor; and a motor support as claimed in claim 1, wherein a stator of the motor is fixed to the inner ring of the motor support.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Further features, details and advantages will become more clearly apparent from reading the description given below by way of illustration and with reference to the following figures.

[0042] FIG. 1 is a schematic side view of one example of a fan device for a heating, ventilation and/or air conditioning device for a motor vehicle.

[0043] FIG. 2 is a schematic perspective view of an assembly formed by the motor support and a housing of the fan device of FIG. 1.

[0044] FIG. 3 is a schematic perspective view of a sub-assembly of the motor support of FIG. 2.

[0045] FIG. 4 is a schematic side view of a detail of the sub-assembly of FIG. 3.

[0046] FIG. 5 is a schematic perspective view of a peg used in the motor support of FIGS. 2 and 3.

[0047] FIG. 6 depicts a detail of the sub-assembly of FIG. 3.

[0048] FIG. 7 schematically depicts the detail of FIG. 6.

[0049] FIG. 8 depicts a detail of a first variant of the sub-assembly of FIG. 3.

[0050] FIG. 9 schematically depicts the detail of FIG. 8.

[0051] FIG. 10 depicts a detail of a second variant of the sub-assembly of FIG. 3.

[0052] FIG. 11 schematically depicts the detail of FIG. 10.

[0053] FIG. 12 depicts a detail of a third variant of the sub-assembly of FIG. 3.

[0054] FIG. 13 schematically depicts the detail of FIG. 12.

DETAILED DESCRIPTION

[0055] FIG. 1 schematically illustrates a side view of a fan device 10 for a heating, ventilation and/or air conditioning device for a motor vehicle. In the conventional way, such a heating, ventilation and/or air conditioning device for a motor vehicle comprises a ventilation circuit, a fan device 10 for causing the air to move in the ventilation circuit, and means for heating and/or means for cooling the flow of air set in motion by the fan device 10.

[0056] As illustrated in FIG. 1, the fan device 10 essentially comprises a fan impeller 12 and an electric motor, here hidden by a motor cowl 14, for driving the rotation of the fan impeller 12 about its axis A1. The electric motor is, for example, a brushless motor. The fan device 10 further comprises a motor support 16 allowing the electric motor to be assembled on a support. In this particular instance, the electric motor is connected to a deflector 18 of the motor support 16, the deflector 18 forming part of the ventilation circuit of the heating, ventilation and/or air conditioning device.

[0057] The motor support 16 is described in greater detail in what follows.

[0058] As visible in the figures, the motor support 16 essentially comprises an inner ring 20, an outer ring 22 and a decoupling element 24 interposed between the inner ring 20 and the outer ring 22. The decoupling element 24 is aimed at limiting the transmission of vibrations from one of the two rings 20, 22 to the other of the two rings 20, 22. The decoupling element 24 is formed here by an elastomer ring. By way of example, the elastomer material is SEBS (polystyrene-b-poly(ethylene-butylene)-b-polystyrene). The decoupling ring 24 is, for example, overmolded on the inner ring 20 and outer ring 22. The decoupling ring 24 thus secures together the inner ring 20 and outer ring 22. The inner ring 20, outer ring 22 and decoupling ring 24 are coaxial, having, as common axis, the axis of rotation A of the fan impeller 12.

[0059] The assembly formed by the inner ring 20, outer ring 22 and decoupling ring 24 is housed in a cavity of the deflector 18. The inner ring 20 is secured to the stator (not visible here) of the motor. The outer ring 22 is fixed here to the deflector 18. A layer of elastomer material may be interposed between the outer ring 22 and the deflector 18.

[0060] According to the example depicted in the figures, the inner ring 20 has a plurality of fingers 26. The fingers 26 extend radially outward, from the exterior surface of the inner ring 20. In this particular instance, each finger 26 has an H-shaped cross section, comprising two substantially planar surfaces 26.sub.1, 26.sub.2 connected to one another by a web 26.sub.3. Here, the planar surfaces 26.sub.1, 26.sub.2 are normal to the direction of the axis A1 common to the rings 20, 22, 24. Here, each planar surface 26.sub.1, 26.sub.2 is covered with a layer 27.sub.1, 27.sub.2 of elastomer material.

[0061] In the example illustrated, the inner ring 20 has three fingers 26. The fingers 26 are preferably uniformly angularly distributed about the axis A1 of the inner ring 20.

[0062] The outer ring 22 for its part comprises a plurality of receptacles 28. Each receptacle 28 is designed to accept a respective finger 26. The receptacles 28 thus open at least onto the radially internal surface of the outer ring 22. In this particular instance, the receptacles 28 pass all the way through, opening onto the radially internal surface of the outer ring 22 and onto the radially external surface of the outer ring 22. The receptacles 28 are preferably uniformly angularly distributed about the axis A1 of the outer ring 22.

[0063] The housing of the fingers 26 in the receptacles 28 makes it possible to limit the capacity for relative tilting of the inner ring 20 with respect to the outer ring 22. What is meant here by tilting is any movement of one of the rings 20, 22 with respect to the other 20, 22 outside of the common midplane of the rings 20, 22, normal to the direction of the axis A1 common to the two rings 20, 22.

[0064] In the example illustrated, the receptacles 28 have dimensions such that there is clearance between the walls of each receptacle 28 and the finger 26 housed therein. In particular, there is clearance in the orthoradial direction. The walls of each receptacle 28 are covered here with elastomeric material. As a preference, the layer of elastomer 30 that covers the walls of each receptacle 28 is formed as one with the decoupling ring 24.

[0065] As is more particularly visible in FIG. 4, in each receptacle 28, the finger 26 collaborates with two axial end-stops 32, 34 to further limit the axial movement of the finger 26 in the receptacle 28. Here, the two axial end-stops 32, 34 project from the walls of the receptacle 28. What is meant here by an axial end-stop is a stop that limits movement in the direction of the common axis A1 of the rings 20, 22, 24.

[0066] In the example illustrated, the elastomeric material of one of the layers 27.sub.1, 27.sub.2 is in contact between one of the axial end-stops 32, 34 and one of the planar surfaces 26.sub.1, 26.sub.2 of the finger 26. This then limits the possible travel of the finger 26 in the receptacle 28 in the axial direction A1. In order to limit this axial travel still further, the elastomeric material of the layers 27.sub.1, 27.sub.2 present between the axial end-stops 32, 34 and the planar surfaces 26.sub.1, 26.sub.2 is compressed here. For example, the elastomeric material of the layers 27.sub.1, 27.sub.2 present between the axial end-stops 32, 34 and the planar surfaces 26.sub.1, 26.sub.2 has an axial compression ratio greater than or equal to 5% and/or less than or equal to 25%, preferably substantially equal to 15%. The axial compression ratio ε.sub.1, ε.sub.2 is defined as being the ratio between: [0067] the difference between, on the one hand, the thickness e.sub.1.sup.0, e.sub.2.sup.0 of the layer of elastomer on the planar surfaces 26.sub.1, 26.sub.2 of the fingers 26 before the fingers 26 are placed between the axial end-stops 32, 34, and, on the other hand, the thickness e.sub.1, e.sub.2 of the layer of elastomer 27.sub.1, 27.sub.2 on the planar surfaces 26.sub.1, 26.sub.2 of the fingers 26 after the fingers 26 have been placed between the axial end-stops 32, 34; and [0068] the thickness e.sub.1.sup.0, e.sub.2.sup.0 of the layer of elastomer on the planar surfaces 26.sub.1, 26.sub.2 of the fingers 26 before the fingers 26 are placed between the axial end-stops 32, 34:

[00001]$\begin{array}{cc}{\epsilon }_1=\frac{e_1^0-e_1}{e_1^0},& \left[\mathrm{Math}.1\right]\end{array}$${\epsilon }_2=\frac{e_2^0-e_2}{e_2^0}$

[0069] Thus, the possible deformation of the elastomer material makes it possible to limit the transmission of vibrations from one of the two rings 20, 22 to the other of the two rings 20, 22. At the same time, the compression of the elastomer material of the layers 27.sub.1, 27.sub.2 does, however, limit the movement of the fingers 26 and, as a result, the capacity for relative movement of the two rings 20, 22.

[0070] Also in order to achieve this, the elastomeric material of which the layers 27.sub.1, 27.sub.2 are formed may be chosen according to its hardness. This elastomeric material may notably have a hardness greater than or equal to 25 Shore and/or less than or equal to 60 Shore.

[0071] The thicknesses e.sub.1, e.sub.2, on the one hand, and/or e.sub.1.sup.0, e.sub.2.sup.0, on the other hand, are advantageously substantially equal. This then allows a centering of the fingers 26 between the two axial end-stops 32, 34.

[0072] The elastomeric material of the layers 27.sub.1, 27.sub.2 may advantageously be overmolded on the surfaces 26.sub.1, 26.sub.2 of the fingers 26, particularly at the same time as the overmolding of the decoupling ring 24. The elastomeric material is thus held in position with respect to the fingers 26. This then also makes the inner ring 20 easier to mount with respect to the outer ring 22.

[0073] The first axial end-stop is formed here by a spigot 32 of a peg 36. The peg 36 also comprises a substantially planar base 38 from which the spigot 32 extends along an axis A2 intended to be parallel to the common axis A1 of the rings 20, 22, 24 when the peg 36 is fixed on the outer ring 22. To provide this fixing, the base 38 here has two openings 40 which are intended to be mounted tightly on two complementary cylindrical reliefs formed on the outer ring 22. Furthermore, two notches 42 are provided at the longitudinal ends of the base 38. One of the two notches 42 accepts a complementary rib formed by the outer ring 22, to guide the mounting of the peg 36 on the outer ring 22. The spigot 32 is mounted tightly in a hole in the outer ring 22 so as to project into a receptacle 28 and thus form the first axial end-stop 32. More specifically, the spigot 32 extends in the direction of the common axis A1 of the rings 20, 22, 24, from one of the walls of the receptacle 28, toward the finger 26 housed therein.

[0074] The second axial end-stop 34 is here formed by the deflector 18 which comprises projecting cylindrical reliefs passing through an opening in the outer ring 22 so as to project into the receptacles 28 from an opposite wall to the first axial end-stop 32. The projecting cylinders also extend in a direction parallel to the direction of the axis A1 common to the rings 20, 22, 24.

[0075] Moreover, as is particularly visible in FIGS. 2 and 3, the decoupling ring 24 defines an annular trench 44 between the inner ring 20 and outer ring 22. In this trench 44, the decoupling ring 24 forms blocks 46. The blocks 46 are thus formed as one with the decoupling ring 24. In this instance, the decoupling ring 24 forms six blocks 46. The six blocks 46 here form three pairs of blocks 46 which are substantially uniformly angularly distributed about the axis A1. Each pair of blocks 46 comprises, for example, a block 46 on each side of a finger 26.

[0076] The blocks 46 are essentially aimed at reinforcing the decoupling ring 24, notably in the direction of the common axis A1 of the rings 20, 22, so as to reduce the risk of cracks appearing in the decoupling ring 24. However, the corresponding addition of material, which accentuates the stiffness of the decoupling ring 24, has an accompanying tendency to increase the resonant frequency of the motor support 16, notably of the decoupling ring 24. This increase in the resonant frequency results in a potential increase in the noise in the interior of the vehicle equipped with the motor support 16.

[0077] As a result, the shape of the blocks 46 is chosen so as to allow the stiffness of the decoupling ring 24 to be actually increased in the direction of the common axis A1 of the rings 22, 24, while at the same time limiting the increase in the resonant frequency of the motor support 16. In order to do this, the blocks 46 are substantially H-shaped. Strictly speaking, as illustrated in FIG. 6 for example, the two arms 46int, 46ext are slightly curved, the length Lint of the interior arm 46int being slightly shorter than the length Lext of the exterior arm 46ext. However, in practice, and as has been illustrated in FIG. 7, the block 46 may be considered as being H-shaped with two rectilinear arms 46.sub.1, 46.sub.2 of length L equal to the mean of the lengths Lint, Lext of the interior arm 46int and exterior arm 46ext.

[0078] The two arms 46int, 46ext, respectively 46.sub.1, 46.sub.2, of the H are separated by a distance B, oriented in the radial direction of the rings 20, 22, 24. Each arm 46int, 46ext, respectively 46.sub.1, 46.sub.2, of the H has a width D measured in the radial direction. The web 46a of the H has a width A, measured in the orthoradial direction. The width A of the web 46a and the distance B between the two arms 46int, 46ext, respectively 46.sub.1, 46.sub.2, of the H are such that the ratio A/B is greater than or equal to 1.4. Furthermore, the ratio A/D is greater than or equal to 2. Specifically, the inventors have found that, surprisingly, by conforming to these inequalities, it is possible to strengthen the decoupling ring 24 while at the same time maintaining a relatively low resonant frequency, notably below 75 Hz, preferably below 50 Hz.

[0079] The width A of the web of the H 46 may be greater than or equal to 4 mm and/or less than or equal to 20 mm.

[0080] The distance B between the arms 46int, 46ext, respectively 46.sub.1, 46.sub.2, of the H 46 may be greater than or equal to 3 mm and/or less than or equal to 6 mm.

[0081] The width D of the arms 46int, 46ext, respectively 46.sub.1, 46.sub.2, of the H 46 may be greater than or equal to 2 mm and/or less than or equal to 5 mm.

[0082] In order to further improve the mechanical strength of the assembly, the blocks 46 are advantageously flush with the inner ring 20 and/or with the outer ring 22, in the direction of the common axis A1 of the two rings. To achieve this, the thickness C of the blocks, measured in the direction of the common axis A1 of the rings 20, 22, 24, is preferably greater than or equal to 10 mm, preferably greater than or equal to 14 mm, and/or less than or equal to 20 mm, preferably less than or equal to 16 mm.

[0083] The blocks 46 may still be made of a polymer material, for example SEBS. The polymer material from which the blocks 46 are formed may have a hardness of between 25 and 60 Shore, notably substantially equal to 40 Shore. The use of a substantially softer material makes it possible to limit the resonant frequency of the motor support 16 still further.

[0084] The decoupling ring 24 also forms an annulus 48, here arranged radially between the inner ring 20 and the blocks 46. The annulus 48 for example covers substantially the entire radially external surface of the inner ring 20.

[0085] Variants of the shape of the blocks 46 are described in further detail in what follows, with reference to FIGS. 6 to 13.

[0086] In the example of FIGS. 6 and 7: [0087] the thickness C of the block 46 is, for example, comprised between 10 and 20 mm, notably substantially equal to 14 mm; [0088] the width A of the web is, for example, comprised between 3 and 6 mm, notably substantially equal to 4.4 mm; [0089] the distance B between the arms 46int, 46ext, respectively 46.sub.1, 46.sub.2, of the H is, for example, comprised between 3 mm and 6 mm, notably substantially equal to 3 mm.

[0090] With blocks such as this it has been possible to create a decoupling ring 24 of which the natural frequency was substantially equal to 32 Hz.

[0091] In the example of FIGS. 8 and 9: [0092] the thickness C of the block 46 is, for example, comprised between 10 and 20 mm, notably substantially equal to 16 mm; [0093] the width A of the web is, for example, comprised between 6 and 10 mm, notably substantially equal to 8.8 mm; [0094] the distance B between the arms 46int, 46ext, respectively 46.sub.1, 46.sub.2, of the H is, for example, comprised between 3 mm and 6 mm, notably substantially equal to 6 mm.

[0095] With such a geometry for the blocks 46 it has been possible to create a decoupling ring 24 of which the natural frequency was substantially equal to 32 Hz when a material with a hardness substantially equal to 25 Shore was employed. With the same geometry and a material of a hardness substantially equal to 40 Shore, the natural frequency is substantially equal to 47 Hz.

[0096] In the example of FIGS. 10 and 11: [0097] the thickness C of the block 46 is, for example, comprised between 10 and 20 mm, notably substantially equal to 16 mm; [0098] the width A of the web is, for example, comprised between 6 and 10 mm, notably substantially equal to 8.8 mm; [0099] the distance B between the arms 46int, 46ext, respectively 46.sub.1, 46.sub.2, of the H is, for example, comprised between 3 mm and 6 mm, notably substantially equal to 3 mm.

[0100] With such a geometry for the blocks 46 it has been possible to create a decoupling ring 24 of which the natural frequency was substantially equal to 45 Hz when a material with a hardness substantially equal to 25 Shore was employed. With the same geometry and a material of a hardness substantially equal to 40 Shore, the natural frequency is substantially equal to 67 Hz.

[0101] Finally, in the example of FIGS. 12 and 13: [0102] the thickness C of the block 46 is, for example, comprised between 10 and 20 mm, notably substantially equal to 16 mm; [0103] the width A of the web is, for example, comprised between 10 and 20 mm, notably substantially equal to 12 mm; [0104] the distance B between the arms 46int, 46ext, respectively 46.sub.1, 46.sub.2, of the H is, for example, comprised between 3 mm and 6 mm, notably substantially equal to 6 mm.

[0105] It should be noted that the width A of the web 46a here corresponds to the sum of the two lengths A.sub.1, A.sub.2 measured orthoradially along a median arc of the web 46a, on either side of a hole 50. Here, the two lengths A.sub.1, A.sub.2 are substantially equal such that the hole 50 is substantially in the middle of the median arc of the web 46a. The hole 50 is advantageously a blind hole, so that it does not impair the fluidtightness of the motor support 16. The hole 50 notably makes the decoupling ring 24 and, in particular, blocks 46 of relatively large dimensions, easier to mold. It should be noted here that the web 46a may have more than one hole 50, preferably blind. The length A of the web 46a then corresponds to the sum of the lengths measured on either side of the various holes 50, along a median arc of the web 46a.

[0106] With such a geometry for the blocks 46 it has been possible to create a decoupling ring 24 of which the natural frequency was substantially equal to 35 Hz when a material with a hardness substantially equal to 25 Shore was employed. With the same geometry and a material of a hardness substantially equal to 40 Shore, the natural frequency is substantially equal to 53 Hz.

[0107] The present disclosure is not restricted to the example described hereinabove but encompasses all variants and combinations conceivable to a person skilled in the art within the scope of the protection sought.

[0108] According to a first embodiment variant, one single axial end-stop projects into the receptacles 28. In that case, the finger housed in the receptacle may be clamped between, on the one hand, the projecting axial end-stop and, on the other hand, the opposite wall of the receptacle from the projecting axial end-stop.

[0109] Furthermore, the axial end-stops may be produced using means other than those described in the above example. For example, one and/or the other of the axial end-stops may be produced in the form of a boss on the wall of the receptacle, and extending toward the finger housed in the receptacle.

[0110] Likewise, in the example illustrated, the elastomeric material is present on the faces of the fingers facing the axial end-stops. Alternatively or in addition, elastomeric material may be provided on the axial end-stops, whether or not these project. However, as a preference, contact between two layers of elastomer material is avoided. Thus, as a preference, just one of the two contacting surfaces is covered with elastomeric material.

[0111] Furthermore, in the example illustrated, the inner ring forms fingers housed in receptacles formed in the outer ring. However, the reverse configuration is conceivable, with the outer ring having fingers oriented radially toward the inner ring and housed in receptacles formed in this inner ring.

[0112] It should also be noted that the decoupling element may adopt a form other than that of a decoupling ring.

[0113] The blocks may be distinct from the decoupling ring, the decoupling ring and the blocks then forming a decoupling means.