Fan for a ventilation device of a motor vehicle and method of balancing such a fan

Abstract

Fan for a ventilation device of a motor vehicle and method for balancing such a fan The present invention relates to a fan (10) for a ventilation device of a motor vehicle comprising: - an electric motor (14) comprising a stator (18) and a rotor (20), - a fan wheel (12) secured to the rotor (18), - an internal support (16a) made of plastic material on which the stator (18) is fixed, - an external support (16b) configured to ensure the fixing of the fan (10) on the motor vehicle and arranged at least partially around the internal support (16a), - a plurality of damping elements (28) arranged between the internal support (16a) and the external support (16b),the internal support (16a) comprising a plurality of holding reliefs (32) arranged on an external surface of the internal support (16a) and configured to receive radial holding arms of a fan balancing device (10) and the external support (16b) comprising openings facing the holding reliefs (32) or being axially offset from the internal support (16a) at least facing the holding reliefs (32) to allow the passage of the radial holding arms. Fig.1,

Description

Title of the invention: Fan for a ventilation device of a motor vehicle and method for balancing such a fan

[0001] The present invention relates to a fan configured to be arranged in a ventilation device of a motor vehicle and in particular in a heating, ventilation and air conditioning (HVAC) device. The fan makes it possible to ventilate the air inside the vehicle.

[0002] For this, the fan comprises a fan wheel comprising for example a plurality of blades and driven in rotation by an electric motor.

[0003] However, such a fan produces vibrations which can be significant depending on the size of the fan wheel and its weight, which can lead to inconvenience, particularly noise, for the passengers of the motor vehicle. It is therefore advisable to limit these vibrations as much as possible.

[0004] To this end, it is appropriate on the one hand to have a well-balanced rotating assembly and on the other hand to decouple the fan from the rest of the vehicle to limit the propagation of vibrations.

[0005] In order to achieve such decoupling, it is known to equip the fan with damping pads made of a flexible material capable of absorbing vibrations. These damping pads are, for example, arranged at the stator.

[0006] However, the presence of these damping pads can make it difficult or even impossible to balance the fan since it is necessary to precisely measure the unbalance during rotation of the fan wheel. However, the damping pads are intended precisely to dampen the vibrations linked to the unbalance and transmitted to the outside of the fan.

[0007] Furthermore, in order to reduce the cost and weight of vehicle equipment, more and more parts are made of plastic material, particularly the parts used to support the electric motor driving the fan. Such plastic parts make it difficult to maintain the stator to achieve correct balancing.

[0008] It is therefore appropriate to find a solution making it possible to obtain a fan whose balancing can be carried out easily despite the use of plastic parts and making it possible to limit the vibrations transmitted to the rest of the vehicle during operation of the fan.

[0009] For this purpose, the invention relates to a fan for a ventilation device of a motor vehicle comprising: - an electric motor comprising a stator and a rotor, - a fan wheel attached to the rotor, - an internal support made of plastic material on which the stator is fixed, - an external support configured to ensure the attachment of the fan to the motor vehicle and arranged at least partially around the internal support, - a plurality of damping elements arranged between the internal support and the external support, wherein the internal support comprises a plurality of holding reliefs provided on an external surface of the internal support and configured to receive radial holding arms of a fan balancing device and wherein the external support comprises openings facing the holding reliefs or is axially offset from the internal support at least facing the holding reliefs to allow the passage of the radial holding arms.

[0010] Such a fan makes it possible to balance the fan easily without having to dismantle the fan and without the balancing being disturbed by the damping pads allowing the fan to be decoupled from the other elements of the motor vehicle so as to improve passenger comfort.

[0011] According to another aspect of the present invention, the inner support and the outer support are rings.

[0012] According to another aspect of the present invention, the holding reliefs are provided on a radially external face of the internal support.

[0013] According to another aspect of the present invention, the holding reliefs are produced by removing material.

[0014] According to another aspect of the present invention, the material recesses have an inwardly converging profile.

[0015] According to another aspect of the present invention, the internal support and the external support are made of plastic material, for example acrylonitrile butadiene styrene.

[0016] According to another aspect of the present invention, the damping elements are pads made of rubber, for example ethylene-propylene-diene monomer.

[0017] According to another aspect of the present invention, the fan comprises at least three holding reliefs, the holding reliefs being regularly distributed around the internal support.

[0018] According to another aspect of the present invention, the holding reliefs are angularly offset relative to the damping elements.

[0019] The present invention also relates to a method for balancing a fan as described previously by a balancing device comprising a plurality of radial holding arms, the distal end of which has a shape complementary to the holding reliefs, the method comprising: - a step of positioning the end of the plurality of holding arms respectively on the plurality of holding reliefs for holding the internal support directly by the arms of the mounting device, - a fan balancing step in which the vibrations transmitted by the fan to the balancing device via the holding arms are measured when the fan is operated to rotate the fan wheel and then in which weights are fixed on the fan wheel at positions determined by the balancing device.

[0020] According to another aspect of the present invention, the weights are made by staples which are fixed on blades of the fan wheel.

[0021] According to another aspect of the present invention, the vibrations transmitted by the fan are measured by accelerometers arranged on the balancing device.

[0022] Other advantages and characteristics will appear on reading the description of several illustrative but non-limiting examples of the present invention, as well as the appended drawings in which:

[0023] [Fig-1] [Fig. 1] is a schematic perspective and sectional representation of a fan according to an embodiment of the present invention;

[0024] [Fig.2] [Fig.2] is a schematic perspective representation of the fan of [Fig.l];

[0025] [Fig.3] [Fig.3] is a schematic perspective representation of a support internal of the fan of [Fig.l];

[0026] [Fig.4] [Fig.4] is a schematic perspective representation of a support external of the fan of [Fig.l];

[0027] [Fig.5] [Fig.5] is a flowchart of the steps in a balancing process of a fan according to the present invention.

[0028] The following embodiments are examples. Although the description refers to one or more embodiments, this does not necessarily mean that each reference relates to the same embodiment, or that the features apply only to a single embodiment. Single features of different embodiments may also be combined or interchanged to provide other embodiments.

[0029] In the present description, certain elements or parameters may be indexed, such as for example first element or second element as well as first parameter and second parameter or even first criterion and second criterion, etc. In this case, it is a simple indexing to differentiate and name elements or parameters or criteria that are close, but not identical. This indexing does not imply a priority of one element, parameter or criterion over another and such names can easily be interchanged without departing from the scope of the present description. This indexing also does not imply an order in time for example to assess this or that criterion.

[0030] Figures 1 and 2 schematically illustrate a fan 10 for a motor vehicle ventilation device, for example a motor vehicle heating, ventilation and / or air conditioning installation. [Fig. 1] is a perspective and sectional view and [Fig. 2] is a perspective view.

[0031] The fan 10 comprises a fan wheel 12, an electric motor 14, and a support device 16 for the electric motor 14. The fan wheel 12 rotates about an axis AL. The electric motor 14 is intended to drive the fan wheel 12 in rotation about the axis Al. The fan wheel 12 comprises, for example, a plurality of blades 120 distributed around the periphery of the fan wheel 12.

[0032] The electric motor 14 comprises a stator 20 and an associated rotor 18. This is an external rotor 18 in that it is associated with a stator 20 arranged radially inside the rotor 18 but other configurations are possible.

[0033] The rotor 18 may in particular comprise a cup 22 symmetrical by rotation around the axis A1, in the shape of a bell. The rotor 20 also comprises magnets 24 fixed here to an internal face of the cup 22, in particular on a cylindrical strip of the internal face of the cup 22. The cup 22 of the rotor 18 is fixed, at its center, to a shaft 26 of axis A1. The shaft 26 constitutes the output (or rotation) shaft of the electric motor 14, driving the fan wheel 12. For this purpose, the fan wheel 12 is here directly fixed on the shaft 26.

[0034] The stator 20 can be symmetrical by rotation around the axis AL. The stator 20 comprises a barrel 46 extending mainly in the direction of the axis AL. The cup 22 of the rotor 18 in particular covers one end of the barrel 46 opposite its base 46a.

[0035] The support device 16 of the electric motor 14 is in particular intended to allow the fan 10 to be fixed in a motor vehicle, by limiting the transmission of vibrations generated by the electric motor 14 and / or the fan wheel 12 in the motor vehicle and / or external constraints towards the electric motor 14 and / or the fan wheel 12.

[0036] For this, the support device 16 comprises an internal support 16a, for example a ring which may be made of plastic material, for example acrylonitrile butadiene styrene, on which the stator 18 of the electric motor 14 is fixed. [Fig.3] represents such an internal support 16a.

[0037] The internal support 16a comprises a plurality of holding reliefs 32 arranged on its external surface, i.e. its surface oriented radially outwards. In the example of [Fig. 3], the internal support 16a comprises three holding reliefs 32. The holding reliefs 32 are for example produced by material removals. The material removals may have a profile converging towards the inside (section which decreases towards the bottom of the material removal), for example concave recesses as shown in [Fig. 3]. Such material removals facilitate the positioning of the end of the radial arms of the balancing device. Other shapes such as convex or spherical protuberances are also possible (in this case, the end of the radial arms of the balancing device will have a concave or spherical hollow shape). The holding reliefs 32 are configured to receive one end of the radial holding arms of a balancing device (not shown) of the fan 10, the end of the radial holding arms having a shape complementary to the shape of the holding reliefs 32. In the example shown, the end of the radial holding arms is configured to fit into the hollow formed by the holding relief 32 as indicated by the arrows F. The stator 20 is fixed to the internal support 16a, for example via screws.

[0038] The support device 16 also comprises an external support 16b, for example a ring made of plastic material, in particular acrylonitrile butadiene styrene. [Fig. 4] represents an example of an external support 16b. The external support 16b may be arranged concentrically with the internal support 16a. The external support 16b is configured to ensure the fixing of the fan 12 on the motor vehicle, for example via screws positioned in orifices 30 located at the periphery of the external support 16b. In the example of [Fig. 4], the external support comprises a plurality of axial extensions 31, six in the present case, configured to come opposite the internal support 16a in the mounted state of the fan 10 so that the external support 16b is arranged at least partially around the internal support 16a.However, the external support 16b comprises openings arranged opposite the holding reliefs 32 or is axially offset from the internal support 16a at least opposite the holding reliefs 32 to allow the passage of the radial holding arms of the balancing device. In the example of [Fig.4], the external support 16b is axially offset from the internal support 16a except at the level of the axial extensions 31 which are angularly offset relative to the holding reliefs 32 so that in the mounted state of the fan, the holding reliefs are accessible by the radial arms of the balancing device.

[0039] The support device 16 also comprises a plurality, six in the case of [Fig.l], of damping elements 28 (visible in [Fig.2]) arranged between the internal support 16a and the external support 16b. In the present example, the damping elements 28 are arranged between the axial extensions 31 of the external support 16b and the internal support 16a. The damping elements 28 are for example made of pads made of rubber, for example ethylene-propylene-diene monomer or elastomeric material. However, other materials making it possible to limit the transmission of vibrations between the internal support 16a and the external support 16b can also be used. The damping elements 28 have, for example, an H shape, but other shapes are also possible. In the present example, the damping elements 28 are arranged on either side of the holding reliefs 32, but other positions are possible, for example a regular distribution around the internal support 16a.

[0040] The internal support 16a and the external support 16b are configured so that the holding reliefs 32 are visible and accessible in the mounted state of the fan 10 so as to be able to position the end of the radial holding arms of the balancing device without having to dismantle the fan 10. For this, the holding reliefs 32 are offset angularly or axially relative to the damping pads 28 in particular.

[0041] Such a configuration makes it possible to maintain the internal support 16a during balancing and thus to be able to achieve balancing that is not disturbed by the damping elements 28. Indeed, the purpose of carrying out a balancing method is to measure the unbalance of the fan 10 during its operation so as to position weights making it possible to reduce the unbalance. However, such an unbalance measurement cannot be carried out correctly if damping elements such as the damping elements 28 are positioned between the holding arms of the balancing device and the device whose unbalance is to be reduced, here the assembly comprising the electric motor 14 and the fan wheel 12.

[0042] The present invention also relates to a method for balancing the fan 10 described previously by a balancing device comprising a plurality of radial holding arms whose distal end has a shape complementary to the holding reliefs 32.

[0043] [Fig.5] represents a flowchart of the different stages of the process.

[0044] The first step 101 concerns the positioning of the end of the plurality of holding arms of the balancing device respectively on the plurality of holding reliefs 32 as indicated by the arrows F. Once positioned, the holding arms make it possible to hold the internal support 16a in position (so that there are no damping elements 28 between the holding arms and the electric motor 14). The internal support 16a is thus held directly by the arms of the balancing device.

[0045] The second step 102 concerns a step of balancing the fan 10. In this step, the fan 10 is actuated so as to drive the fan wheel 12 in rotation and the vibrations transmitted by the fan 10 to the balancing device are measured. These vibrations are for example measured by accelerometers arranged on the holding arms or other elements of the balancing device. The balancing device is configured to determine an unbalance of the fan wheel. fan wheel 12 and to determine the mass and position of the weights to be added to the fan wheel 12 to obtain a balanced fan wheel, i.e. without unbalance. The weights are for example fixed on the blades or fins of the fan wheel 12. The weights can be made in the form of staples.

[0046] Step 102 may also comprise an optional sub-step corresponding to the positioning of the weights on the fan wheel 12. The positioning may be carried out automatically by the balancing device.

[0047] Thus, the use of a fan 10 comprising an internal support 16a supporting the stator 20 and an external support 16b fixed to the motor vehicle between which damping elements 28 are arranged makes it possible to limit the transmission of vibrations from the fan 10 to the other elements of the motor vehicle. In addition, the use of accessible holding reliefs 32 provided in the internal support 16a makes it possible to simply fix the electric motor 14 to the balancing device in order to carry out a balancing process of the fan 10 without the need to dismantle the fan 10 and without damping elements 28 disturbing the measurements during the balancing process.

Claims

Claims

1. Fan (10) for a ventilation device of a motor vehicle comprising: - an electric motor (14) comprising a stator (20) and a rotor (18), - a fan wheel (12) integral with the rotor (18), - an internal support (16a) made of plastic material on which the stator (20) is fixed, - an external support (16b) configured to ensure the fixing of the fan (10) on the motor vehicle and arranged at least partially around the internal support (16a), - a plurality of damping elements (28) arranged between the internal support (16a) and the external support (16b),characterized in that the internal support (16a) comprises a plurality of holding reliefs (32) provided on an external surface of the internal support (16a) and configured to receive radial holding arms of a fan balancing device (10) and in that the external support (16b) comprises openings facing the holding reliefs (32) or is axially offset from the internal support (16a) at least facing the holding reliefs (32) to allow the passage of the radial holding arms.,

2. A fan (10) according to claim 1 wherein the inner support (16a) and the outer support (16b) are rings.

3. Fan (10) according to one of the preceding claims in which the holding reliefs (32) are provided on a radially external face of the internal support (16a).

4. Fan (10) according to one of the preceding claims in which the holding reliefs (32) are produced by material removals.

5. Fan (10) according to the preceding claim in which the material recesses have a profile converging towards the inside.

6. Fan (10) according to one of the preceding claims in which the internal support (16a) and the external support (16b) are made of plastic material, for example acrylonitrile butadiene styrene.

7. Fan (10) according to one of the preceding claims in which the damping elements (28) are pads made of rubber, for example ethylene-propylene-diene monomer.

8. Fan (10) according to one of the preceding claims comprising at least three holding reliefs (32), the holding reliefs (32) being distributed regularly around the internal support (16a).

9. Fan (10) according to one of the preceding claims in which the holding reliefs (32) are angularly offset relative to the damping elements (28).

10. A method of balancing a fan (10) according to one of the preceding claims by a balancing device comprising a plurality of radial holding arms, the distal end of which has a shape complementary to the holding reliefs (32), the method comprising: - a step (101) of positioning the end of the plurality of holding arms respectively on the plurality of holding reliefs (32) to hold the internal support (16a) directly by the arms of the mounting device, - a step (102) of balancing the fan (10) in which the vibrations transmitted by the fan (10) to the balancing device are measured via the holding arms when the fan (10) is actuated to rotate the fan wheel (12) and then in which weights are fixed on the fan wheel (12) at positions determined by the balancing device.

11. Balancing method according to the preceding claim in which the weights are produced by staples which are fixed on fins (120) of the fan wheel (12).

12. A balancing method according to claim 10 or 11 wherein the vibrations transmitted by the fan (10) are measured by accelerometers arranged on the balancing device.

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